U.S. patent application number 11/837539 was filed with the patent office on 2008-07-17 for methods, compositions and articles of manufacture for enhancing survivability of cells, tissues, organs, and organisms.
Invention is credited to Eric Blackstone, Dana Miller, Mike Morrison, Mark B. Roth.
Application Number | 20080171726 11/837539 |
Document ID | / |
Family ID | 36764069 |
Filed Date | 2008-07-17 |
United States Patent
Application |
20080171726 |
Kind Code |
A1 |
Roth; Mark B. ; et
al. |
July 17, 2008 |
Methods, Compositions and Articles of Manufacture for Enhancing
Survivability of Cells, Tissues, Organs, and Organisms
Abstract
The present invention concerns the use of oxygen antagonists and
other active compounds for inducing stasis or pre-stasis in cells,
tissues, and/or organs in vivo or in an organism overall, in
addition to enhancing their survivability. It includes
compositions, methods, articles of manufacture and apparatuses for
enhancing survivability and for achieving stasis or pre-stasis in
any of these biological materials, so as to preserve and/or protect
them. In specific embodiments, there are also therapeutic methods
and apparatuses for organ transplantation, hyperthermia, wound
healing, hemorrhagic shock, cardioplegia for bypass surgery,
neurodegeneration, hypothermia, and cancer using the active
compounds described.
Inventors: |
Roth; Mark B.; (Seattle,
WA) ; Morrison; Mike; (Seattle, WA) ;
Blackstone; Eric; (Seattle, WA) ; Miller; Dana;
(Seattle, WA) |
Correspondence
Address: |
FULBRIGHT & JAWORSKI L.L.P.
600 CONGRESS AVE., SUITE 2400
AUSTIN
TX
78701
US
|
Family ID: |
36764069 |
Appl. No.: |
11/837539 |
Filed: |
August 12, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11408734 |
Apr 20, 2006 |
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11837539 |
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60673037 |
Apr 20, 2005 |
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60673295 |
Apr 20, 2005 |
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60713073 |
Aug 31, 2005 |
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60731549 |
Oct 28, 2005 |
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60762462 |
Jan 26, 2006 |
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Current U.S.
Class: |
514/144 ;
514/126; 514/184; 514/514; 514/526; 514/553; 514/621; 514/706 |
Current CPC
Class: |
A61P 9/10 20180101; A01N
1/02 20130101; A01N 1/0226 20130101; A61K 31/165 20130101; A61K
31/095 20130101; A61K 31/26 20130101; A61K 31/275 20130101; A61K
31/66 20130101; A61P 43/00 20180101; A61P 7/06 20180101; A61K
31/095 20130101; A61P 7/00 20180101; A61K 33/04 20130101; A61P 9/00
20180101; A61P 7/04 20180101; A61K 2300/00 20130101; A61K 45/06
20130101; A61K 2300/00 20130101; A61K 2300/00 20130101; A61K
2300/00 20130101; A61K 2300/00 20130101; A61K 2300/00 20130101;
A61K 2300/00 20130101; A61K 31/21 20130101; A61K 2300/00 20130101;
A61P 41/00 20180101; A61K 31/21 20130101; A61K 31/185 20130101;
A61K 31/26 20130101; A61K 31/555 20130101; A61K 31/66 20130101;
Y10S 514/921 20130101; A61K 31/555 20130101; A61K 31/185 20130101;
A61K 31/165 20130101; A61P 17/02 20180101; A61K 31/275
20130101 |
Class at
Publication: |
514/144 ;
514/126; 514/184; 514/514; 514/526; 514/553; 514/621; 514/706 |
International
Class: |
A61K 31/66 20060101
A61K031/66; A61K 31/555 20060101 A61K031/555; A61K 31/185 20060101
A61K031/185; A61K 31/165 20060101 A61K031/165; A61K 31/275 20060101
A61K031/275; A61K 31/26 20060101 A61K031/26; A61K 31/095 20060101
A61K031/095; A61K 31/21 20060101 A61K031/21; A61P 43/00 20060101
A61P043/00 |
Goverment Interests
[0002] The government may own fights in the present invention
pursuant to grant number GM048435 from the National Institute of
General Medical Sciences (NIGMS).
Claims
1.-66. (canceled)
67. A method for enhancing survivability of biological matter
comprising administering to the matter an effective amount of an
compound having Formula I and/or Formula IV, or a salt or prodrug
thereof, wherein Formula I and IV comprise: ##STR00006## wherein X
is N, O Po, S, Se, or Te; wherein Y is N or O; wherein R.sub.1 is
H, C, lower alkyl, a lower alcohol, or CN; wherein R.sub.1 is H, C,
lower alkyl, or a lower alcohol, or CN; wherein n is 0 or 1;
wherein m is 0 or 1; wherein k is 0, 1, 2, 3, or 4; and, wherein p
is 1 or 2; ##STR00007## wherein: X is N, O, P, Po, S, Se, Te, O--O,
Po--Po, S--S, Se--Se, or Te--Te, n and m are independently 0 or 1;
and wherein R.sup.21 and R.sup.22 are independently hydrogen, halo,
cyano, phosphate, thio, alkyl, alkenyl, alkynyl, alkoxy,
aminoalkyl, cyanoalkyl, hydroxyalkyl, haloalkyl, hydroxyhaloalkyl,
alkylsulfonic acid, thiosulfonic acid, alkylthiosulfonic acid,
thioalkyl, alkylthio, alkylthioalkyl, alkylaryl, carbonyl,
alkylcarbonyl, haloalkylcarbonyl, alkylthiocarbonyl, aminocarbonyl,
aminothiocarbonyl, alkylaminothiocarbonyl, haloalkylcarbonyl,
alkoxycarbonyl, aminoalkylthio, hydroxyalkylthio, cycloalkyl,
cycloalkenyl, aryl, aryloxy, heteroaryloxy, heterocyclyl,
heterocyclyloxy, sulfonic acid, sulfonic alkyl ester, thiosulfate,
or sulfonamido; and Y is cyano, isocyano, amino, alkyl amino,
aminocarbonyl, aminocarbonyl alkyl, alkylcarbonylamino, amidino,
guanidine, hydrazino, hydrazide, hydroxyl, alkoxy, aryloxy,
hetroaryloxy, cyloalkyloxy, carbonyloxy, alkylcarbonyloxy,
haloakylcarbonyloxy, arylcarbonyloxy, carbonylperoxy,
alkylcarbonylperoxy, arylcarbonylperoxy, phosphate, alkylphosphate
esters, sulfonic acid, sulfonic alkyl ester, thiosulfate,
thiosulfenyl, sulfonamide, --R.sup.23R.sup.24, wherein R.sup.23 is
S, SS, Po, Po--Po, Se, Se--Se, Te, or Te--Te, and R.sup.24 is
defined as for R.sup.21 herein, or Y is ##STR00008## wherein X,
R.sup.21 and R.sup.22, are as defined herein.
68.-149. (canceled)
150. The method of claim 67, wherein X is sulfur.
151. The method of claim 67, wherein said salt is a sulfide salt
selected from the group consisting of sodium sulfide (Na.sub.2S),
sodium hydrogen sulfide (NaHS), potassium sulfide (K.sub.2S)
potassium hydrogen sulfide (KHS), lithium sulfide (Li.sub.2S),
rubidium sulfide (Rb.sub.2S), cesium sulfide (Cs.sub.2S), ammonium
sulfide ((NH.sub.4).sub.2S), ammonium hydrogen sulfide
(NH.sub.4)HS, beryllium sulfide (BeS), magnesium sulfide (MgS),
calcium sulfide (CaS), strontium sulfide (SrS), barium sulfide
(BaS).
152. The method of claim 67, wherein the compound is H.sub.2S,
H.sub.2Se, H.sub.2Te, or H.sub.2Po.
153. The method of claim 152, wherein the compound is H.sub.2S.
154. The method of claim 67, wherein the compound is provided to
the biological as a gas, semi-solid liquid, liquid, or solid.
155. The method of claim 67, wherein the biological matter is a
patient.
156. The method of claim 155, wherein the patient is provided with
the compound before, during, or after an injury, the onset or
progression of a disease, or hemorrhaging in the patient.
157. The method of claim 156, wherein the injury involves
hemorrhaging.
158. The method of claim 154, wherein the active compound is
bubbled into a liquid.
159. The method of claim 154, wherein the active compound is
dissolved into the liquid.
160. The method of claim 155, wherein the patient is provided the
compound by administration to the biological matter intravenously,
intradermally, intraarterially, intraperitoneally, intralesionally,
intracranially, intraarticularly, intraprostatically,
intrapleurally, intratracheally, intranasally, intrathecally,
intravitreally, intravaginally, intrarectally, topically,
intratumorally, intramuscularly, intraperitoneally, intraocularly,
subcutaneously, subconjunctival, intravesicularlly, mucosally,
intrapericardially, intraumbilically, intraocularally, orally,
topically, locally, by inhalation, by injection, by infusion, by
continuous infusion, by localized perfusion, via a catheter, or via
a lavage.
161. The method of claim 160, wherein the compound is administered
to the patient intravenously.
162. The method of claim 161, wherein the patient has a disease or
adverse medical condition.
163. The method of claim 162, wherein the disease or adverse
medical condition is selected from the group consisting of
hemorrhagic shock, myocardial infarction, cardiac arrest,
ischemia/reperfusion injury, unstable angina, post-angioplasty,
aneurysm, trauma, stroke, coronary artery bypass graft (CABG)
surgery, and blood loss.
164. The method of claim 162, wherein the patient is identified as
in need of treatment.
Description
[0001] This application is related to U.S. Provisional Patent
Applications 60/673,037 and 60/673,295 both filed on Apr. 20, 2005,
as well as U.S. Provisional Patent Application 60/713,073, filed
Aug. 31, 2005, U.S. Provisional Patent Application 60/731,549,
filed Oct. 28, 2005, and U.S. Provisional Patent Application
60/762,462, filed on Jan. 26, 2006, all of which are hereby
incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates generally to the field of cell
biology and physiology. More particularly, it concerns methods,
compositions and apparatuses for enhancing survivability of and/or
reducing damage to cells, tissues, organs, and organisms,
particularly under adverse conditions, including but not limited to
hypoxic or anoxic states, using one or more substances, including
those that compete with oxygen. In certain embodiments, the present
invention includes methods, compositions and apparatuses for
treating, preventing, and diagnosing diseases and conditions by
exposing a subject to an oxygen antagonist, protective metabolic
agent, or other chemical compound discussed herein, or a precursor
thereof, that can achieve its stated goal (collectively referred to
as "active compounds").
[0005] 2. Description of Related Art
[0006] Stasis is a Latin term meaning "standstill." In the context
of stasis in living tissues, the most common forms of stasis relate
to the preservation of tissues for transplant or reattachment.
Typically, such tissues are immersed in a physiologic fluid, such
as saline, and placed in the cold to reduce biochemical processes
leading to cellular damage. This stasis is incomplete and cannot be
relied upon for extended periods. In fact, the success of organ
transplant and limb reattachment is inversely related to the time
the organ or limb is out of contact with the intact organism.
[0007] A more extreme version of stasis involves placing an entire
organism into what is known colloquially as "suspended animation."
Though still considered largely within the realm of science
fiction, some notoriety has been achieved when wealthy individuals
have sought to be cryopreserved after death, in the hope that
future medical breakthroughs will permit their revival and cure of
their fatal ailments. Allegedly, more than one hundred people have
been cryopreserved since the first attempt in 1967, and more than
one thousand people have made legal and financial arrangements for
cryonics with one of several organizations, for example, Alcor Life
Extension Foundation. Such methods involve the administration of
anti-ischemic drugs, low temperature preservation, and methods to
perfuse whole organisms with cryosuspension fluids. It has not yet
been substantiated that this form of organismal stasis is
reversible.
[0008] The utility of inducing stasis in biological matter as
contemplated by the compositions, methods, or articles of
manufacture described herein, is characterized by induction or
onset of stasis followed by a period of time in which the stasis is
maintained, followed then by reversion to a normal or near normal
physiological state, or a state that one skilled in the art would
recognize as a state that is better than the state of the
biological matter had it never undergone stasis, in whole or in
part. Stasis can also be defined as what it is not. Organismal
stasis is not any of the following states: sleep, comatose, death,
anesthetized, or grand mal seizure.
[0009] There are numerous reports of individuals who have survived
apparent cessation of pulse and respiration after exposure to
hypothermic conditions, usually in cold-water immersion. Though not
fully understood by scientists, the ability to survive such
situations likely derives from what is called the "mammalian diving
reflex." This reflex is believed to stimulate the vagal nervous
system, which controls the lungs, heart, larynx and esophagus, in
order to protect vital organs. Presumably, cold-water stimulation
of nerve receptors on the skin causes shunting of blood to the
brain and to the heart, and away from the skin, the
gastrointestinal tract and extremities. At the same time, a
protective reflex bradycardia, or slowing of the heart beat,
conserves the dwindling oxygen supplies within the body.
Unfortunately, the expression of this reflex is not the same in all
people, and is believed to be a factor in only 10-20% percent of
cold-water immersion cases.
[0010] Compositions and methods that do not rely fully or at all on
hypothermia and/or oxygen may be useful in the context of organ
preservation, as well as for tissue or cell preservation. Cells and
tissue are currently preserved using hypothermia, frequently at
temperatures substantially below freezing, such as in liquid
nitrogen. However, dependence on temperature can be problematic, as
apparatuses and agents for producing such low temperatures may not
be readily available when needed or they may require replacement.
For example, tissue culture cells are often stored for periods of
time in tanks that hold liquid nitrogen; however, these tanks
frequently require that the liquid nitrogen in the unit be
periodically replaced, otherwise it becomes depleted and the
temperature is not maintained. Furthermore, damage to cells and
tissue occurs as a result of the freeze/thaw process. Thus,
improved techniques are needed.
[0011] Moreover, the lack of ability to control cellular and
physiologic metabolism in whole organisms subjected to traumas such
as amputation and hypothermia is a key shortcoming in the medical
field. On the other hand, the anecdotal evidence discussed above
strongly suggests that if properly understood and regulated, it is
possible to induce stasis in cells, tissues and whole organisms.
Thus, there is a great need for improved methods for controlling
metabolic processes particularly under traumatic conditions.
SUMMARY OF THE INVENTION
[0012] Therefore, the present invention provides methods,
compositions, articles of manufacture, and apparatuses to induce
stasis in cells, tissues and organs located within or derived from
an organism, as well as in the organism itself. Such methods,
compositions, articles of manufacture, and apparatuses can be
employed to protect biological matter, as well as to prevent,
treat, or diagnose diseases and conditions in the organism. In
addition, such methods may directly induce stasis themselves, or
they may act indirectly by not inducing stasis themselves, but by
enhancing the ability of biological matter to enter stasis in
response to an injury or disease condition, e.g., by reducing the
time or level of injury or disease required to achieve stasis. Such
a condition may be referred to as pre-stasis. Details of such
applications and other uses are described below.
[0013] The invention is based, in part, on studies with compounds
that were determined to have a protective function, and thus, serve
as protective agents. Moreover, the overall results of studies
involving different compounds indicate that compounds with an
available electron donor center are particularly effective in
inducing stasis or pre-stasis. In addition, these compounds induce
reversible stasis, meaning they are not so toxic to the particular
biologic matter that the matter dies or decomposes. It is further
contemplated that the present invention can be used to enhance
survivability of and/or to prevent or reduce damage to biological
matter, which may be subject to or under adverse conditions.
[0014] In particular embodiments, methods of the present invention
are used to induce stasis or pre-stasis in biological matter, e.g.,
cells, tissues, organs, and/or organisms, after an injury (e.g., a
traumatic injury) or after the onset or progression of a disease,
in order to protect the biological matter from damage associated
with the injury or disease prior to, during, or following treatment
of the injury or disease. In other embodiments, methods of the
present invention are used to induce or promote stasis or
pre-stasis in biological matter prior to subjection to an injurious
event (e.g., an elective surgery) or prior to the onset or
progression of a disease, in order to protect the biological matter
from damage associated with adverse conditions such as injury or
disease. Such methods are generally referred to as "pre-treatment"
with an active compound. Pre-treatment includes methods wherein
biological matter is provided with an active compound both before
and during, and before, during and after biological matter is
subjected to adverse conditions (e.g., an injury or onset or the
progression of a disease), and methods wherein biological matter is
provided with an active compound only before biological matter is
subjected to adverse conditions.
[0015] According to various embodiments of the methods of the
present invention, stasis may be induced by treating biological
matter with an active compound that induces stasis directly itself
or, alternatively, by treating biological matter with an active
compound that does not itself induce stasis, but instead, promotes
or enhances the ability of or decreases the time required for the
biological matter to achieve stasis in response to another stimuli,
such as, but not limited to, an injury, a disease, hypoxia,
excessive bleeding, or treatment with another active compound.
[0016] In particular embodiments, treatment with an active compound
induces "pre-stasis," which refers to a hypometabolic state through
which biological matter must transition to reach stasis. Pre-stasis
is characterized by a reduction in metabolism within the biological
material of a magnitude that is less than that defined as stasis.
In order to achieve stasis using an active compound, the biological
matter necessarily must transition through a graded hypometabolic
state in which oxygen consumption and CO.sub.2 production are
reduced less than two-fold in the biological matter. Such a
continuum, in which metabolism or cellular respiration is reduced
by an active compound to a degree less than two-fold, can be
described as a state of "pre-stasis".
[0017] To the extent that stasis comprises a two-fold reduction
(i.e., a reduction to 50% or less) in either CO.sub.2 production or
O.sub.2 consumption, direct measurement of these parameters in the
biological matter using methods known to those in the art in which
a reduction of less than two-fold is detected is indicative of
pre-stasis. Accordingly, certain measurements of carbon dioxide and
oxygen levels in the blood as well as other markers of metabolic
rate familiar to those skilled in the art including, but not
limited to, blood pO.sub.2, VO.sub.2, pCO.sub.2, pH, and lactate
levels, may be used in the instant invention to monitor the onset
or progression of pre-stasis. While indicators of metabolic
activity, e.g., CO.sub.2 production via cellular respiration and
O.sub.2 consumption, are reduced less than two-fold as compared to
normal conditions, pre-stasis may be associated with an at least
10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% reduction in
CO.sub.2 evolution, which refers to the amount of CO.sub.2 released
from the lungs. In addition, in various embodiments, pre-stasis is
characterized by a reduction in one or more indicators of metabolic
activity that is less than or equal to 1%, 2%, 5%, 10%, 15%, 20%,
25%, 30%, 35%, 40%, 45%, or 49% as compared to normal physiological
conditions. In other embodiments, pre-stasis is characterized by
its ability to enhance or promote entry into stasis in response to
another stimuli (wherein the another stimuli may include prolonged
treatment with the same active agent), or its ability to enhance
survival of or protect biological matter from damage resulting from
an injury, the onset or progression of the disease, or bleeding,
particularly bleeding that can lead to irreversible tissue damage,
hemorrhagic shock, or lethality.
[0018] While methods of the present invention explicitly
exemplified herein may refer to inducing "stasis," it is understood
that these methods may be readily adapted to induce "pre-stasis,"
and that such methods of inducing pre-stasis are contemplated by
the present invention. In addition, the same active compounds used
to induce stasis may also be used to induce pre-stasis, by
providing them to biological matter at a lower dosage and/or for a
shorter time than used to induce stasis.
[0019] In certain embodiments, the present invention involves
exposing biological matter to an amount of an agent, so as to
achieve stasis of the biological matter. In some embodiments, the
present invention concerns methods for inducing stasis in in vivo
biological matter comprising: a) identifying an organism in which
stasis is desired; and, b) exposing the organism to an effective
amount of an oxygen antagonist or other active compound to induce
stasis in the in vivo biological matter. Inducing "stasis" in
biological matter means that the matter is alive but is
characterized by one or more of the following: at least a two-fold
reduction in the rate or amount of carbon dioxide production by the
biological matter; at least a two-fold (i.e., 50%) reduction in the
rate or amount of oxygen consumption by the biological matter; and
at least a 10% decrease in movement or motility (applies only to
cells or tissue that move, such as sperm cells or a heart or a
limb, or when stasis is induced in the entire organism)
(collectively referred to as "cellular respiration indicators"). In
certain embodiments of the invention, it is contemplated that there
is about, at least about, or at most about a 2-, 3-, 4-, 5-, 6-,
7-, 8-, 9-, 10-, 15-, 20-, 25-, 30-, 35-, 40-, 45-, 50-, 60-, 70-,
80-, 90-, 100-, 150-, 200-, 250-, 300-, 350-, 400-, 450-, 500-,
600-, 700-, 800-, 900-, 1000-, 1100-, 1200-, 1300-, 1400-, 1500-,
1600-, 1700-, 1800-, 1900-, 2000-, 2100-, 2200-, 2300-, 2400-,
2500-, 2600-, 2700-, 2800-, 2900-, 3000-, 3100-, 3200-, 3300,
3400-, 3500-, 3600-, 3700-, 3800-, 3900-, 4000-, 4100-, 4200-,
4300-, 4400-, 4500-, 5000-, 6000-, 7000-, 8000-, 9000-, or
10000-fold or more reduction in the rate of oxygen consumption by
the biological matter, or any range derivable therein.
Alternatively, it is contemplated that embodiments of the invention
may be discussed in terms of a reduction in the rate of oxygen
consumption by the biological matter as about, at least about, or
at most about 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62,
63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96,
97, 98, 99% or more, or any range derivable therein. It is
contemplated that any assay to measure oxygen consumption may be
employed, and a typical assay will involve utilizing a closed
environment and measuring the difference between the oxygen put
into the environment and oxygen that is left in the environment
after a period of time. It is further contemplated that carbon
dioxide production can be measured to determine the amount of
oxygen consumption by biological matter. Thus, there may be
decreases in carbon dioxide production, which would correspond to
the decreases in oxygen consumption discussed above.
[0020] In methods of the invention, stasis or pre-stasis is
temporary and/or reversible, meaning that the biological matter no
longer exhibits the characteristics of stasis at some later point
in time. In some embodiments of the invention, instead of an oxygen
antagonist, a compound that is not does not qualify as an oxygen
antagonist is administered. It is contemplated that methods
discussed with respect to oxygen antagonists may be applied with
respect to any compound that is an oxygen antagonist, protective
metabolic agent, compound with the structure of Formula I, II, III,
or IV, any other compound discussed herein, or a salt or precursor
thereof. A compound that achieves any method of the invention and
qualifies as an oxygen antagonist, protective metabolic agent,
compound with the structure of Formula I, II, III, or IV, or a salt
or precursor thereof, will be considered an "active compound." In
particular embodiments, induction of stasis is desired in which
case the compound may be referred to as an "active stasis
compound." It is contemplated that in some embodiments of the
invention, a method is achieved by inducing stasis. For example,
therapeutic methods may involve inducing stasis, in which case the
active compound is an active stasis compound. It is specifically
contemplated that in embodiments in which active compounds are
discussed, the invention includes, and may be limited to, oxygen
antagonists.
[0021] In certain embodiments of the present invention, biological
matter is treated with an active compound that does not induce
stasis by itself (at least not at the level and/or duration of time
provided), but rather induces biological matter to enter a
pre-stasis state that has therapeutic benefits and that enhances
the ability of the biological matter to achieve stasis in response
to another stimuli, such as, e.g., an injury, disease state, or
treatment with another active compound or the same active compound
If used for a longer duration or greater dosage.
[0022] The term "biological matter" refers to any living biological
material (mammalian biological material in preferred embodiments)
including cells, tissues, organs, and/or organisms, and any
combination thereof. It is contemplated that stasis may be induced
in a part of an organism (such as in cells, in tissue, and/or in
one or more organs), whether that part remains within the organism
or is removed from the organism, or the whole organism will be
placed in a state of stasis. Moreover, it is contemplated in the
context of cells and tissues that homogenous and heterogeneous cell
populations may be the subject of embodiments of the invention. The
term "in vivo biological matter" refers to biological matter that
is in vivo, i.e., still within or attached to an organism.
Moreover, the term "biological matter" will be understood as
synonymous with the term "biological material." In certain
embodiments, it is contemplated that one or more cells, tissues, or
organs is separate from an organism. The term "isolated" can be
used to describe such biological matter. It is contemplated that
stasis may be induced in isolated biological matter.
[0023] An organism or other biological matter in need of stasis is
an organism or biological matter in which stasis of all or part of
the organism may yield direct or indirect physiological benefits.
For example, a patient at risk for hemorrhagic shock may be
considered in need of stasis, or a patient who will undergo
coronary artery bypass surgery may benefit from protecting the
heart from ischemia/reperfusion injury. Other applications are
discussed throughout the application. In some cases, an organism or
other biological matter is identified or determined to be in need
of stasis based on one or more tests, screens, or evaluations that
indicate a condition or disease, or the risk of a condition or
disease that can be prevented or treated by undergoing stasis.
Alternatively, the taking of a patient medical or family medical
history (patient interview) may yield information that an organism
or other biological matter is in need of stasis. As would be
evident to one skilled in the art, one application of the present
invention would be to reduce the overall energy demands of a
biological material by inducing stasis.
[0024] Alternatively, an organism or other biological matter may be
in need of an active compound to enhance survivability. For
instance, a patient may need treatment for an injury or disease or
any other application discussed herein. They may be determined to
be in need of enhanced survivability or treatment based on methods
discussed in the previous paragraph, such as by taking a patient
medical or family medical history.
[0025] The term "oxygen antagonist" refers to a substance that
competes with oxygen insofar as it is used by a biological matter
that requires oxygen for it to be alive ("oxygen-utilizing
biological matter"). Oxygen is typically used or needed for various
cellular processes that create the biological matter's primary
source of readily utilizable energy. An oxygen antagonist
effectively reduces or eliminates the amount of oxygen that is
available to the oxygen-utilizing biological matter, and/or the
amount of oxygen that can be used by the oxygen-utilizing
biological matter. In one embodiment, an oxygen antagonist may
achieve its oxygen antagonism directly. In another embodiment, an
oxygen antagonist may achieve its oxygen antagonism indirectly.
[0026] A direct oxygen antagonist competes with molecular oxygen
for the binding to a molecule (e.g., a protein) that has an oxygen
binding site or oxygen binding capacity. Antagonism may be
competitive, non-competitive, or uncompetitive as known in the art
of pharmacology or biochemistry. Examples of direct oxygen
antagonists include, but are not limited to, carbon monoxide (CO),
which competes for oxygen binding to hemoglobin and to cytochrome c
oxidase.
[0027] An indirect oxygen antagonist influences the availability or
delivery of oxygen to cells that use oxygen for energy production
(e.g., in cellular respiration) in the absence of directly
competing for the binding of oxygen to an oxygen-binding molecule.
Examples of indirect oxygen antagonists include, but are not
limited to, (i) carbon dioxide, which, through a process known as
the Bohr effect, reduces the capacity of hemoglobin (or other
globins, like myoglobin) to bind to oxygen in the blood or
hemolymph of oxygen-utilizing animals, thereby reducing the amount
of oxygen that is delivered to oxygen-utilizing cells, tissues, and
organs of the organism, thereby reducing the availability of oxygen
to cells that use oxygen; (ii) inhibitors of carbonic anhydrase
(Supuran et al., 2003, incorporated by reference in its entirety)
which, by virtue of inhibiting the hydration of carbon dioxide in
the lungs or other respiratory organs, increase the concentration
of carbon dioxide, thereby reducing the capacity of hemoglobin (or
other globins, like myoglobin) to bind to oxygen in the blood or
hemolymph of oxygen-utilizing animals, thereby reducing the amount
of oxygen that is delivered to oxygen-utilizing cells, tissues, and
organs of the organism, thereby reducing the availability of oxygen
to cells that use oxygen; and, (iii) molecules that bind to oxygen
and sequester it from or rendering it unavailable to bind to
oxygen-binding molecules, including, but not limited to oxygen
chelators, antibodies, and the like.
[0028] In some embodiments, an oxygen antagonist is both a direct
and an indirect oxygen antagonist. Examples include, but are not
limited to, compounds, drugs, or agents that directly compete for
oxygen binding to cytochrome c oxidase and are also capable of
binding to and inhibiting the enzymatic activity of carbonic
anhydrase. Thus, in some embodiments an oxygen antagonist inhibits
or reduces the amount of cellular respiration occurring in the
cells, for instance, by binding sites on cytochrome c oxidase that
would otherwise bind to oxygen. Cytochrome c oxidase specifically
binds oxygen and then converts it to water. In some embodiments,
such binding to cytochrome c oxidase is preferably releasable and
reversible binding (e.g., has an in vitro dissociation constant,
K.sub.d, of at least 10.sup.-2, 10.sup.-3, or 10.sup.-4 M, and has
an in vitro dissociation constant, K.sub.d, not greater than
10.sup.-6, 10.sup.-7, 10.sup.-8, 10.sup.-9, 10.sup.-10, or
10.sup.-11 M). In some embodiments, an oxygen antagonist is
evaluated by measuring ATP and/or carbon dioxide output.
[0029] The term "effective amount" means an amount that can achieve
the stated result. In certain methods of the invention, an
"effective amount" is, for example, an amount that induces stasis
in the biological matter in need of stasis. In other methods, an
"effective amount" is, for example, an amount that induces
pre-stasis in biological matter in need of stasis or in need of
enhanced survival. In additional embodiments, an "effective amount"
may refer to an amount that increases the survivability of an
organism or other biological matter. This can be determined (or
assumed) based on comparison or previous comparison to untreated
biological matter or biological matter treated with a different
dosage or regimen that does not experience a difference in
survivability.
[0030] It will be understood that when inducing stasis in a tissue
or organ, an effective amount is one that induces stasis in the
tissue or organ as determined by the collective amount of cellular
respiration of the tissue or organ. Accordingly, for example, if
the level of oxygen consumption by a heart (collectively with
respect to cells of the heart) is decreased at least about 2-fold
(i.e., 50%) after exposure to a particular amount of a certain
oxygen antagonist or other active stasis compound, it will be
understood that that was an effective amount to induce stasis in
the heart. Similarly, an effective amount of an agent that induces
stasis in an organism is one that is evaluated with respect to the
collective or aggregate level of a particular parameter of stasis.
It will be also understood that when inducing stasis in an
organism, an effective amount is one that induces stasis generally
of the whole organism, unless a particular part of the organism was
targeted. In addition, it is understood that an effective amount
may be an amount sufficient to induce stasis by itself, or it may
be an amount sufficient to induce stasis in combination with
another agent or stimuli, e.g., another active compound, an injury,
or a disease state.
[0031] The concept of an effective amount of a particular compound
is related, in some embodiments, to how much utilizable oxygen
there is available to the biological matter. Generally, stasis can
be induced when there is about 100,000 ppm or less of oxygen in the
absence of any oxygen antagonist (room air has about 210,000 ppm
oxygen). The oxygen antagonist serves to alter how much oxygen is
effectively available. At concentration of 10 ppm of oxygen,
suspended animation is induced. Thus, while the actual
concentration of oxygen that biological matter is exposed to may be
higher, even much higher, than 10 ppm, stasis can be induced
because of the competitive effect of an oxygen antagonist with
oxygen for binding to essential oxygen metabolizing proteins in the
biological matter. In other words, an effective amount of an oxygen
antagonist reduces the effective oxygen concentration to a point
where the oxygen that is present cannot be used. This will happen
when the amount of an oxygen antagonist reduces the effective
oxygen concentration below the K.sub.m of oxygen binding to
essential oxygen metabolizing proteins (i.e., comparable to 10 ppm
of oxygen). Accordingly, in some embodiments, an oxygen antagonist
reduces the effective concentration of oxygen by about or at least
about 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, 15-, 20-, 25-, 30-, 35-,
40-, 45-, 50-, 60-, 70-, 80-, 90-, 100-, 150-, 200-, 250-, 300-,
350-, 400-, 450-, 500-, 600-, 700-, 800-, 900-, 1000-, 1100-,
1200-, 1300-, 1400-, 1500-, 1600-, 1700-, 1800-, 1900-, 2000-,
2100-, 2200-, 2300-, 2400-, 2500-, 2600-, 2700-, 2800-, 2900-,
3000-, 3100-, 3200-, 3300, 3400-, 3500-, 3600-, 3700-, 3800-,
3900-, 4000-, 4100-, 4200-, 4300-, 4400-, 4500-, 5000-, 6000-,
7000-, 8000-, 9000-, or 10000-fold or more, or any range derivable
therein. Alternatively, it is contemplated that embodiments of the
invention may be discussed in terms of a reduction in effective
oxygen concentration as about, at least about, or at most about 50,
51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67,
68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,
85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99% or
more, or any range derivable therein. It is understood that this is
another way of indicating a decrease in cellular respiration.
[0032] Furthermore, in some embodiments, stasis can be measured
indirectly by a drop in core body temperature of an organism. It is
contemplated that a reduction in core body temperature of about, at
least about, or at most about 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,
31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
48, 49, 50.degree. F. or more, or any range derivable therein may
be observed in methods of the invention. In some embodiments of the
invention, hypothermia can be induced, such as moderate hypothermia
(at least 10.degree. F. reduction) or severe hypothermia (at least
20.degree. F. reduction).
[0033] Moreover, the effective amount can be expressed as a
concentration with or without a qualification on length of time of
exposure. In some embodiments, it is generally contemplated that to
induce stasis or achieve other stated goals of the invention, the
biological matter is exposed to an oxygen antagonist or other
active compound for about, at least about, or at most about 5, 10,
15, 20, 25, 30, 35, 40, 45, 50, 55, 60 seconds, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3, 4, 5, 6, 7
days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12
months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20 or more years, and any combination or range derivable
therein. It is further contemplated that the amount of time may be
indefinite, depending on the reason or purpose for administering
the oxygen antagonist or other active compound. Thereafter,
biological matter may continue to be exposed to an oxygen
antagonist or other active compound, or, in other embodiments of
the invention, the biological matter may no longer be exposed to
the oxygen antagonist or other active compound. This latter step
can be achieved either by removing or effectively removing the
oxygen antagonist or other active compound from the presence of the
biological matter in which stasis was desired, or the biological
matter may be removed from an environment containing the oxygen
antagonist or other active compound. Additionally, matter may be
exposed to or provided with any active compound continuously (a
period of time without a break in exposure), intermittently
(exposure on multiple occasions), or on a periodic basis (exposure
on multiple occasions on a regular basis). The dosages of the
active compound on these different bases may the same or they may
vary. In certain embodiments, an active compound is provided
periodically by providing or exposing biological matter to an
active compound 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 times every 1, 2,
3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,
38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,
55, 56, 57, 58, 59, 60 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3,
4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20 or more years, or any range derivable
therein.
[0034] Furthermore, in some embodiments of the invention,
biological matter is exposed to or provided with an active compound
for a sustained period of time, where "sustained" means a period of
time of at least about 2 hours. In other embodiments, biological
matter may be exposed to or provided with an active compound on a
sustained basis for more than a single day. In such circumstances,
the biological matter is provided with an active compound on a
continuously sustained basis. In certain embodiments, biological
matter may be exposed to or provided with an active compound for
about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more hours (or any
range derivable therein) for 2, 3, 4, 5, 6, 7 days, and/or 1, 2, 3,
4, 5 weeks, and/or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 months,
and/or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20 or more years (or any range derivable therein)
continuously, intermittently (exposure on multiple occasions), or
on a periodic basis (exposure on a recurring regular basis).
[0035] In some embodiments, biological matter may be exposed to or
provided with an active compound at least before and during;
before, during, and after; during and after; or solely after a
particular injury, trauma, or treatment (for instance, surgery),
adverse condition or other relevant event or situation. This
exposure may or may not be sustained.
[0036] The dosages of the active compound on these different bases
may the same or they may vary.
[0037] Moreover, in certain embodiments, an active compound may be
provided on a continously sustained basis at level that is
considered "low," meaning a level that is less than the amount that
causes metabolic flexibility such as seen with drop in CBT, heart
rate, or CO.sub.2 or O.sub.2 consumption or production.
[0038] In certain embodiments, biological matter is exposed or
provided an active compound, such as a metabolic agent, in an
amount that exceeds what was previously understood to be the
maximum tolerated dose before adverse physiological ramifications
such as apnea ("period of time during which breathing is markedly
reduced such that the subject takes 10% or fewer number of
breaths"), lack of observable skeletal muscle movement, dystonia,
and/or hyperactivity. Such an amount may be particularly relevant
to increasing survivability in some embodiments of the invention,
for instance, to increase the chances of surviving adverse
conditions, such as those that would induce death from hemorrhagic
shock.
[0039] A physiological state can be induced by active compounds of
the present invention which enhances survivability in an organism
in need of survivability enhancement and comprises a set of
observable physiological changes in response to an effective dose
of an active compound, said changes may comprise one, more or all
of hyperpnea, apnea and the concomitant or subsequent loss of
neuromuscular tone or voluntary control of movement with continued
heartbeat. A transient and measurable change in arterial blood
color may also be observed. Hyperpnea refers to rapid, shallow
breathing. Apnea refers to a cessation of breathing or the
reduction as described above.
[0040] In certain embodiments, the subject becomes apneic, which is
marked by a cessation in breathing and then an apnic breath after a
short period of time. In rats, this occurs after approximately 20
seconds. Thus, it is contemplated that a subject induced into apnea
may exhibit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10% the number of breaths
subsequent to exposure to an active compound. The subject may have
an occasional breath, which may be considered an apnic breath,
thereafter. In certain embodiments of the invention, apnea
continues until the subject is no longer exposed to the active
compound.
[0041] In some embodiments of the invention, an effective amount
may be expressed as LD.sub.50, which refers to the "median lethal
dose," which means the dose that is administered that kills half
the population of animals (causes 50% mortality). Moreover, in
further embodiments, an effective amount may be independent of the
weight of the biological matter ("weight independent"). In rodents
and humans, for example, the LD.sub.50 of H.sub.2S gas is
approximately 700 ppm before adverse physiological effects occur.
Moreover, in some embodiments of the invention, increasing
survivability refers generally to living longer, which is an
embodiment of the invention.
[0042] The present invention also concerns methods for inducing
apnea in an organism comprising administering to the organism an
effective amount of an active compound. In certain embodiments, the
organism also does not exhibit any skeletal muscle movement as a
result of the active compound. It is specifically contemplated that
the organism may be mammal, including a human. In other
embodiments, an effective amount exceeds what is considered a
lethal concentration. In further embodiments, the concentration may
be a lethal amount though the exposure time may be about, at least
about, or at most about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
seconds, 1, 2, 3, 4, 5 minutes or more (or any range derivable
therein or any other time period specified in this disclosure). In
particular embodiments, a mammal is exposed to at least about 600
ppm of an active gas compound, such as H.sub.2S.
[0043] Additionally, in certain embodiments, there is a step of
identifying an animal in need of treatment. In other embodiments,
there is a step of observing apnea in the organism. In even further
embodiments, methods involving obtaining a blood sample from the
organism and/or evaluating the color of the organism's blood. It
has been observed that exposure to H.sub.2S changes the color of
blood from a mammal; it goes from bright red to a darker, red wine
color and then to brick red. Evaluating the color may be done
visually without any instruments or machines, while in other
embodiments, an instrument may be used, such as a
spectrophotometer. Furthermore, a blood sample may be obtained from
an organism and other types of analysis may be done on it.
Alternatively, a blood sample may not be needed and instead, blood
may be evaluated without the sample. For instance, a modified
pulse-oximeter that shines IR or visible light through the finger
may be employed to monitor color changes in the blood.
[0044] In certain embodiments, biological matter is exposed to an
effective amount of an active compound that does not lead to stasis
or pre-stasis. In some embodiments, there may be no evidence of a
reduction in oxygen consumption or carbon dioxide production while
the active compound is present.
[0045] In additional embodiments, an organism may be exposed to the
active compound while sleeping. Moreover, as discussed above, the
exposure may be regular, such as daily (meaning exposure at least
once a day).
[0046] It is specifically contemplated that in some embodiments an
active compound is provided to a subject by nebulizer. This may be
applied with any embodiment of the invention. In certain cases, the
nebulizer is used for the treatment of hemorrhagic shock. In
further embodiments, the active compound is provided as a single
dose to the subject. In specific cases, a single dose or multiple
doses is one that would induce apnea in a subject. In some
embodiments, a subject is given at least about 1,000, 2,000, 3,000,
4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 11,000, 12,000 or
more ppm H.sub.2S gas. The exposure time may be any of the times
discussed herein, including about or about at most 10, 9, 8, 7, 6,
5, 4, 3, 2, 1, 0.5, 0.1 minutes or less (or any range derivable
therein).
[0047] In further embodiments, after exposure to an active compound
the metabolic rate of biologic matter may change. In certain
embodiments, the RQ ratio (CO.sub.2 production/O.sub.2 consumption)
of the biological matter changes after exposure to an active
compound. This may occur after an initial exposure or repeated
exposure or after an acute exposure. In some embodiments, the RQ
ratio decreases after exposure. The decrease may be a decrease of
about, at least about or at most about 5, 10, 15, 20, 25, 30, 35,
40, 45, 50, 55, 60, 65, 70, 75, 80% or more, or any range derivable
therein. The decrease may be a result of O.sub.2 consumption
increasing of CO.sub.2 production decreasing in relation to O.sub.2
consumption.
[0048] In some embodiments, no other physiological change is
observed in biological matter exposed to the active compound except
that its RQ ratio changes after the exposure. Therefore, in some
embodiments of the invention, methods involve measuring an RQ ratio
in a subject. This may occur before and/or after exposure to the
active compound.
[0049] Therefore, in some embodiments of the invention, stasis is
induced, and a further step in methods of the invention is to
maintain the relevant biological matter in a state of stasis. This
can be accomplished by continuing to expose the biological matter
to an oxygen antagonist or other active compound and/or exposing
the biological matter to a nonphysiological temperature or another
oxygen antagonist or other active compound. Alternatively, the
biological matter may be placed in a preservation agent or
solution, or be exposed to normoxic or hypoxic conditions. It is
contemplated that biological matter may be maintained in stasis for
about, at least about, or at most about 30 seconds, 1, 2, 3, 4, 5,
10, 15, 20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more years, and any
combination or range derivable therein. Moreover, it is
contemplated that in addition to or instead of changing the
temperature, other changes in the environment may be implemented
such as a change in pressure or to effect a cryoprotectant or
cryopreservation environment (e.g., one containing glycerol).
[0050] It will be appreciated that "stasis" with respect to a whole
animal and "stasis" with respect to cells or tissues may require
different lengths of time in stasis. Thus, with respect to human
subjects, e.g., subjects undergoing a surgical treatment, treatment
for malignant hyperthermia, or trauma victim, a time of stasis of
up to 12, 18, or 24 hours is generally contemplated. With respect
to non-human animal subjects, e.g. non-human animals shipped or
stored for commercial purposes, stasis for a period of 2 or 4 days,
2 or 4 weeks, or longer is contemplated.
[0051] The term "expose" is used according to its ordinary meaning
to indicate that biological matter is subjected to an oxygen
antagonist or other active compound. This can be achieved in some
embodiments by contacting biological matter with an oxygen
antagonist or active compound. In other embodiments, this is
achieved by contacting the biological matter with an active
compound, which may or may not be an oxygen antagonist. In the case
of in vivo cells, tissues, or organs, "expose" may further mean "to
lay open" these materials so that it can be contacted with an
oxygen antagonist or other active compound. This can be done, for
example, surgically. Exposing biological matter to an oxygen
antagonist or other active compound can be by incubation in or with
(includes immersion) the antagonist, perfusion or infusion with the
antagonist, injection of biological matter with an oxygen
antagonist or other active compound, or applying an oxygen
antagonist or other active compound to the biological matter. In
addition, if stasis of the entire organism is desirable, inhalation
or ingestion of the oxygen antagonist or other active compound, or
any other route of pharmaceutical administration is contemplated
for use with oxygen antagonists or other active compound.
Furthermore, the term "provide" is used according to its ordinary
and plain meaning to mean "to supply." It is contemplated that a
compound may be provided to biological matter in one form and be
converted by chemical reaction to its form as an active compound.
The term "provide" encompasses the term "expose" in the context of
the term "effective amount," according to the present
invention.
[0052] In some embodiments, an effective amount is characterized as
a sublethal dose of the oxygen antagonist or other active compound.
In the context of inducing stasis of cells, tissues, or organs (not
the whole organism), a "sublethal dose" means a single
administration of the oxygen antagonist or active compound that is
less than half of the amount of the oxygen antagonist or active
compound that would cause at least a majority of cells in a
biological matter to die within 24 hours of the administration. If
stasis of the entire organism is desired, then a "sublethal dose"
means a single administration of the oxygen antagonist or active
compound that is less than half of the amount of the oxygen
antagonist that would cause the organism to die within 24 hours of
the administration. In other embodiments, an effective amount is
characterized as a near-lethal dose of the oxygen antagonist or
active compound. Similarly, in the context of inducing stasis of
cells, tissues, or organs (not the whole organism), a "near lethal
dose" means a single administration of the oxygen antagonist or
active compound that is within 25% of the amount of the inhibitor
that would cause at least a majority of cell(s) to die within 24
hours of the administration. If stasis of the entire organism is
desired, then a "near lethal dose" means a single administration of
the oxygen antagonist or active compound that is within 25% of the
amount of the inhibitor that would cause the organism to die within
24 hours of the administration. In some embodiments a sublethal
dose is administered by administering a predetermined amount of the
oxygen antagonist or active compound to the biological material. It
is specifically contemplated that this may be implemented with
respect to any active compound.
[0053] Furthermore, it is contemplated that in some embodiments an
effective amount is characterized as a supralethal dose of the
oxygen antagonist or other active compound. In the context of
inducing stasis of cells, tissues, or organs (not the whole
organism), a "supra-lethal dose" means a single administration of
an active compound that is at least 1.5 times (1.5.times.) the
amount of the active compound that would cause at least a majority
of cells in a biological matter to die within 24 hours of the
administration. If stasis of the entire organism is desired, then a
"supra-lethal dose" means a single administration of the active
compound that is at least 1.5 times the amount of the active
compound that would cause the organism to die within 24 hours of
the administration. It is specifically contemplated that the
supra-lethal dose can be about, at least about, or at most about
1.5.times., 2.times., 3.times., 4.times., 5.times., 10.times.,
20.times., 30.times., 40.times., 50.times., 60.times., 70.times.,
80.times., 90.times., 100.times., 150.times., 200.times.,
250.times., 300.times., 400.times., 500.times., 600.times.,
700.times., 800.times., 900.times., 1000.times., 1100.times.,
1200.times., 1300.times., 1400.times., 1500.times., 1600.times.,
1700.times., 1800.times., 1900.times., 2000.times., 3000.times.,
4000.times., 5000.times., 6000.times., 7000.times., 8000.times.,
9000.times., 10,000.times. or more, or any range derivable therein,
the amount of the active compound that would cause at least a
majority of cells in a biological matter (or the entire organism)
to die within 24 hours of the administration.
[0054] The amount of the active compound that is provided to
biological matter can be about, at least about, or at most about 1,
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,
38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54,
55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88,
89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 110, 120, 130,
140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260,
270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390,
400, 410, 420, 430, 440, 441, 450, 460, 470, 480, 490, 500, 510,
520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640,
650, 660, 670, 680, 690, 700, 710, 720, 730, 740, 750, 760, 770,
780, 790, 800, 810, 820, 830, 840, 850, 860, 870, 880, 890, 900,
910, 920, 930, 940, 950, 960, 970, 980, 990, 1000 mg, mg/kg, or
mg/m2, or any range derivable therein. Alternatively, the amount
may be expressed as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,
66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,
83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,
100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220,
230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350,
360, 370, 380, 390, 400, 410, 420, 430, 440, 441, 450, 460, 470,
480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600,
610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730,
740, 750, 760, 770, 780, 790, 800, 810, 820, 830, 840, 850, 860,
870, 880, 890, 900, 910, 920, 930, 940, 950, 960, 970, 980, 990,
1000 mM or M, or any range derivable therein.
[0055] In some embodiments an effective amount is administered by
monitoring, alone or in combination, the amount of oxygen
antagonist or other active compound administered, monitoring the
duration of administration of the oxygen antagonist or other active
compound, monitoring a physiological response (e.g., pulse,
respiration, pain response, movement or motility, metabolic
parameters such as cellular energy production or redox state, etc.)
of the biological material to the administration of the oxygen
antagonist or other active compound and reducing, interrupting or
ceasing administration of the compound(s) when a predetermined
floor or ceiling for a change in that response is measured, etc.
Moreover, these steps can be employed additionally in any method of
the invention.
[0056] Tissue in a state of stasis or that has undergone stasis can
be used in a number of applications. They can be used, for example,
for transfusion or transplantation (therapeutic applications,
including organ transplants); for research purposes; for screening
assays to identify, characterize, or manufacture other compounds
that induce stasis; for testing a sample from which the tissue was
obtained (diagnostic applications); for preserving or preventing
damage to the tissue that will be placed back into the organism
from which they were derived (preventative applications); and for
preserving or preventing damage to them during transport or
storage. Details of such applications and other uses are described
below. The term "isolated tissue" means that the tissue is not
located within an organism. In some embodiments, the tissue is all
or part of an organ. The terms "tissue" and "organ" are used
according to their ordinary and plain meanings. Though tissue is
composed of cells, it will be understood that the term "tissue"
refers to an aggregate of similar cells forming a definite kind of
structural material. Moreover, an organ is a particular type of
tissue.
[0057] The present invention concerns methods for inducing stasis
in isolated tissue comprising: a) identifying the tissue in which
stasis is desired; and, b) exposing the tissue to an effective
amount of an oxygen antagonist to induce stasis.
[0058] Compositions, methods, and articles of manufacture of the
invention can be used on biological matter that will be transferred
back into the donor organism from which it was derived (autologous)
or a different recipient (heterologous) subject. In some
embodiments, biological matter is obtained directly from a donor
organism. In others, the biological matter is placed in culture
prior to exposure to an oxygen antagonist or other active compound.
In some situations, the biological matter is obtained from a donor
organism administered extracorporeal membrane oxygenation prior to
retrieval of the biological matter, which is a technique
implemented to aid in the preservation of biological matter.
Moreover, methods include administering or implanting the
biological matter in which stasis was induced to a live recipient
organism.
[0059] In some embodiments, an organ or tissue to be retrieved and
then transplanted is exposed to the oxygen antagonist or other
active compound while still in the donor subject. It is
contemplated that in some cases, the vasculature of the donor is
used to expose the organ or tissue to the oxygen antagonist or
other active compound. This can be done if the heart is still
pumping or a pump, catheter, or syringe can be used to administer
the oxygen antagonist or other active compound into the vasculature
for delivery to the organ or tissue
[0060] Methods of the invention also concern inducing stasis in
isolated tissue comprising incubating the tissue with an oxygen
antagonist or active stasis compound that creates hypoxic
conditions for an effective amount of time for the tissue to enter
stasis.
[0061] Cells in a state of stasis or that have undergone stasis can
be used in a number of applications. They can be used, for example,
for transfusion or transplantation (therapeutic applications); for
research purposes; for screening assays to identify, characterize,
or manufacture other compounds that induce stasis; for testing a
sample from which the cells were obtained (diagnostic
applications); for preserving or preventing damage to the cells
that will be placed back into the organism from which they were
derived (preventative applications); and for preserving or
preventing damage to cells during transport or storage. Details of
such applications and other uses are described below.
[0062] The present invention concerns methods for inducing stasis
in one or more cells separate from an organism comprising: a)
identifying the cell(s) in which stasis is desired; and, b)
exposing the cell(s) to an effective amount of an oxygen antagonist
or other active stasis compound to induce stasis.
[0063] It is contemplated that the cell may be any oxygen-utilizing
cell. The cell may be eukaryotic or prokaryotic. In certain
embodiments, the cell is eukaryotic. More particularly, in some
embodiments, the cell is a mammalian cell. Mammalian cells
contemplated for use with the invention include, but are not
limited to those that are from a: human, monkey, mouse, rat,
rabbit, hamster, goat, pig, dog, cat, ferret, cow, sheep, and
horse.
[0064] Moreover, cells of the invention may be diploid but in some
cases, the cells are haploid (sex cells). Additionally, cells may
be polyploid, aneuploid, or anucleate. The cell can be from a
particular tissue or organ, such as one from the group consisting
of: heart, lung, kidney, liver, bone marrow, pancreas, skin, bone,
vein, artery, cornea, blood, small intestine, large intestine,
brain, spinal cord, smooth muscle, skeletal muscle, ovary, testis,
uterus, and umbilical cord. Moreover, the cell can also be
characterized as one of the following cell types: platelet,
myelocyte, erythrocyte, lymphocyte, adipocyte, fibroblast,
epithelial cell, endothelial cell, smooth muscle cell, skeletal
muscle cell, endocrine cell, glial cell, neuron, secretory cell,
barrier function cell, contractile cell, absorptive cell, mucosal
cell, limbus cell (from cornea), stem cell (totipotent, pluripotent
or multipotent), unfertilized or fertilized oocyte, or sperm.
[0065] The present invention also provides methods, compositions,
and apparati for enhancing survivability of and/or reducing damage
to biological matter under adverse conditions by reducing metabolic
demand, oxygen requirements, temperature, or any combination
thereof in the biological matter of interest. In some embodiments
of the invention, survivability of biological matter is enhanced by
providing it with an effective amount of a protective metabolic
agent. The agent enhances survivability by preventing or reducing
damage to the biological matter, preventing all or part of the
matter from dying or senescing, and/or extending the lifespan of
all or part of the biological matter, relative to biological matter
not exposed to the agent. Alternatively, in some embodiments the
agent prolongs survival of tissue and/or an organism that would
otherwise not survive without the agent.
[0066] It is contemplated that a "protective metabolic agent" is a
substance or compound capable of reversibly altering the metabolism
of biological matter that is exposed to or contacted with it and
that promotes or enhances the survivability of the biological
matter.
[0067] In certain embodiments, the protective metabolic agent
induces stasis in the treated biological matter; while, in other
embodiments, the protective metabolic agent does not directly
itself induce stasis in the treated biological matter. Protective
metabolic agents, and other active compounds, may enhance
survivability and/or reduce damage to biological matter without
inducing stasis in the biological matter per se, but rather by
reducing cellular respiration and corresponding metabolic activity
to a degree that is less than about a fifty percent decrease in
oxygen consumption or carbon dioxide production. Additionally, such
compounds may cause the biological matter to more quickly, easily,
or effectively enter into or achieve stasis in response to an
injury or disease state, e.g., by inducing the biological matter to
achieve a state of pre-stasis.
[0068] Survivability includes survivability when the matter is
under adverse conditions--that is, conditions under which there can
be adverse and nonreversible damage or injury to biological matter.
Adverse conditions can include, but are not limited to, when oxygen
concentrations are reduced in the environment (hypoxia or anoxia,
such as at high altitudes or under water); when the biological
matter is incapable of receiving that oxygen (such as during
ischemia), which can be caused by i) reduced blood flow to organs
(e.g., heart, brain, and/or kidneys) as a result of blood vessel
occlusion (e.g., myocardial infarction, and/or stroke), ii)
extracorporeal blood shunting as occurs during heart/lung bypass
surgery (e.g., "pumphead syndrome" in which heart or brain tissue
is damaged as a result of cardiopulmonary bypass), or iii) as a
result of blood loss due to trauma (e.g., hemorrhagic shock or
surgery); hypothermia, where the biological material is subjected
to sub-physiological temperatures, due to exposure to cold
environment or a state of low temperature of the biological
material, such that it is unable to maintain adequate oxygenation
of the biological materials; hyperthermia, whereby temperatures
where the biological material is subjected to supra-physiological
temperatures, due to exposure to hot environment or a state of high
temperature of the biological material such as by a malignant
fever; conditions of excess heavy metals, such as iron disorders
(genetic as well as environmental) such as hemochromatosis,
acquired iron overload, sickle-cell anemia, juvenile
hemochromatosis African siderosis, thalassemia, porphyria cutanea
tarda, sideroblastic anemia, iron-deficiency anemia and anemia of
chronic disease. It is contemplated that a protective metabolic
agent is an oxygen antagonist in certain embodiments of the
invention. It is also contemplated that in certain other
embodiments, an oxygen antagonist is not a protective metabolic
agent. In other embodiments of the invention, one or more compounds
may be used to increase or enhance survivability of biological
matter; reversibly inhibit the metabolism and/or activity of
biological matter; reduce the oxygen requirement of biological
matter; reduce or prevent damage to biological matter under adverse
conditions; prevent or reduce damage or injury to biological
matter; prevent aging or senescence of biological matter; and,
provide a therapeutic benefit as described throughout the
application with respect to oxygen antagonists. It is contemplated
that embodiments relating to inducing stasis are applicable to
these other embodiments as well. Therefore, any embodiment
discussed with respect to stasis may be implemented with respect to
these other embodiments.
[0069] An active compound used for inducing stasis or any of these
other embodiments may lead or provide their desired effect(s), in
some embodiments, only when they are in the context of the
biological matter (i.e., have no lasting effect) and/or they may
provide for these effect(s) for more than 24 hours after the
biological matter is no longer exposed to it. Moreover, this can
also be the case when a combination of active compounds is
used.
[0070] In certain embodiments, biological matter is exposed to an
amount of an oxygen antagonist or other active compound that
reduces the rate or amount of carbon dioxide production by the
biological matter at least 2-fold, but also by about, at least
about, or at most about 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, 15-, 20-,
25-, 30-, 35-, 40-, 45-, 50-, 100-, 200-, 300-, 400-, 500-fold of
more, or any range derivable therein. Alternatively, it is
contemplated that embodiments of the invention may be discussed in
terms of a reduction in the rate or amount of carbon dioxide
production by the biological matter as about, at least about, or at
most about 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,
81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,
98, 99% or more, or any range derivable therein. In still further
embodiments, biological matter is exposed to an amount of an oxygen
antagonist or other active compound that reduces the rate or amount
of oxygen consumption by the biological matter at least 2-fold, but
also by about, at least about, or at most about 3-, 4-, 5-, 6-, 7-,
8-, 9-, 10-, 15-, 20-, 25-, 30-, 35-, 40-, 45-, 50-, 100-, 200-,
300-, 400-, 500-fold of more, or any range derivable therein.
Alternatively, it is contemplated that embodiments of the invention
may be discussed in terms of a reduction in the rate or amount of
oxygen consumption by the biological matter as about, at least
about, or at most about 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60,
61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,
78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,
95, 96, 97, 98, 99% or more, or any range derivable therein. In
still further embodiments, biological matter is exposed to an
amount of an oxygen antagonist or other active compound that
decreases movement or motility by at least 10%, but also by about,
at least about, or at most about 15, 20, 25, 30, 35, 40, 45, 50,
55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or 100%, or any range
derivable therein. As with other embodiments, these characteristics
and parameters are in the context of whichever biological matter is
induced into a state of stasis. Thus, if stasis is induced in an
organism's heart, these parameters would be evaluated for the
heart, and not the whole organism. In the context of organisms, a
reduction in oxygen consumption on the order of roughly 8-fold is a
kind of stasis referred to as "hibernation." Moreover, it will be
understood in this application that a reduction in oxygen
consumption on the order of around 1000-fold can be considered
"suspended animation." It will be understood that embodiments of
the invention concerning stasis can be achieved at the level of
hibernation or suspended animation, if appropriate. It is
understood that a "-fold reduction" is relative to the reduced
amount; for example, if a non-hibernating animal consumes 800 units
of oxygen, the hibernating animal consumes 100 units of oxygen.
[0071] Additionally, in some embodiments of the invention, methods
are provided for reducing cellular respiration, which may or may
not be as high as that needed to reach stasis. A reduction in
oxygen consumption by about, at least about, or at most about 1, 2,
5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85,
90, 95, or 100% is provided in methods of the invention. This can
also be expressed and assessed in terms of any cellular respiration
indicator.
[0072] It is contemplated that biological matter may be exposed to
one or more oxygen antagonists or other active compounds more than
one time. It is contemplated that biological matter may be exposed
to one or more active compounds 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or
more times, meaning when a biological matter is exposed multiple
times that there are periods of respite (with respect to exposure
to the active compound) in between.
[0073] It is also contemplated that an active compound may be
administered before, during, after, or any combination thereof, in
relation to the onset or progression of an injurious insult or
disease condition. In certain embodiments, pre-treatment of
biological matter to an active compound is sufficient to enhance
survivability and/or reduce damage from an injurious or disease
insult. Pre-treatment is defined as exposure of the biological
matter to the active compound before the onset or detection of the
injurious or disease insult. Pre-treatment can be followed by
termination of exposure at or near the onset of the insult or
continued exposure after the onset of insult.
[0074] In certain embodiments, methods including pre-exposure to an
active compound (i.e., pre-treatment) are used to treat conditions
in which an injurious or disease insult is 1) scheduled or elected
in advance, or 2) predicted in advance to likely occur. Examples
meeting condition 1 include, but are not limited to, major surgery
where blood loss may occur spontaneously or as a result of a
procedure, cardiopulmonary bypass in which oxygenation of the blood
may be compromised or in which vascular delivery of blood may be
reduced (as in the setting of coronary artery bypass graft (CABG)
surgery), or in the treatment of organ donors prior to removal of
donor organs for transport and transplantation into a recipient in
need of an organ transplant. Examples meeting condition 2 include,
but are not limited to, medical conditions in which a risk of
injury or disease progression is inherent (e.g., in the context of
unstable angina, following angioplasty, bleeding aneurysms,
hemorrhagic strokes, following major trauma or blood loss), or in
which the risk can be diagnosed using a medical diagnostic
test.
[0075] Exposure to the active compound may enhance survivability or
reduce damage when exposure occurs after the onset or detection of
the injurious or disease insult to achieve a therapeutic effect.
Exposure to the active compound may be brief or extended. The
exposure duration may be only for as long as needed to reach an
indicator of stasis activity or pre-stasis (e.g., blood pCO.sub.2,
pO.sub.2, pH, lactate, or sulfhemoglobin levels, or body
temperature), or it may be longer. In certain embodiments, exposure
occurs following traumatic injury (including iatrogenic and/or
non-iatrogenic injuries) to an organism and is used to induce
stasis or pre-stasis in the entire organism or injured tissue
therein, so as to prevent or minimize damage, e.g., ischemic and
reperfusion injury prior to, during, and/or following
treatment.
[0076] In one embodiment, the present invention includes a method
of protecting a mammal from suffering cellular damage from a
surgery, comprising providing to the mammal an amount of hydrogen
sulfide or other active compound sufficient to induce the mammal to
enter pre-stasis prior to the surgery. The surgery may be elective,
planned, or emergency surgery, such as, e.g., cardiopulmonary
surgery. The hydrogen sulfide may be administered by any means
available in the art, including, e.g., intravenously or by
inhalation.
[0077] In another embodiment, the present invention includes a
method of protecting a mammal from suffering cellular damage from a
disease or adverse medical condition, comprising providing to the
mammal an amount of hydrogen sulfide or other active compound
sufficient to induce the mammal to enter pre-stasis or stasis prior
to the onset or progression of the disease or adverse medical
condition. This embodiment may be used in the context of a variety
of different diseases and adverse medical conditions, including,
e.g., unstable angina, post-angioplasty, aneurism, hemorrhagic
stroke or shock, trauma, and blood loss.
[0078] In specific embodiments, the invention concerns methods of
preventing an organism, such as a mammal, from bleeding to death or
suffering irreversible tissue damage as a result of bleeding by
providing to the mammal an amount of hydrogen sulfide or other
active compound sufficient to prevent the animal from bleeding to
death. In certain additional embodiments, the organism may go into
hemorrhagic shock but not die from excessive bleeding. The terms
"bleeding" and "hemorrhaging" are used interchangeably to refer to
any discharge of blood from a blood vessel. It includes, but is not
limited to, internal and external bleeding, bleeding from an injury
(which may be from an internal source, or from an external physical
source such as from a gunshot, stabbing, physical trauma,
etc.).
[0079] Moreover, additional embodiments of the invention concern
prevention of death or irreversible tissue damage from blood loss
or other lack of oxygenation to cells or tissue, such as from lack
of an adequate blood supply. This may be the result of, for
example, actual blood loss, or it may be from conditions or
diseases that prevent cells or tissue from being perfused (e.g.,
reperfusion injury), that cause blockage of blood to cells or
tissue, that reduce blood pressure locally or overall in an
organism, that reduce the amount of oxygen is carried in the blood,
or that reduces the number of oxygen carrying cells in the blood.
Conditions and diseases that may be involved include, but are not
limited to, blood clots and embolisms, cysts, growths, tumors,
anemia (including sickle cell anemia), hemophilia, other blood
clotting diseases (e.g., von Willebrand, ITP), and atherosclerosis.
Such conditions and diseases also include those that create
essentially hypoxic or anoxic conditions for cells or tissue in an
organism because of an injury, disease, or condition.
[0080] In some cases, a sublethal collective dose or a nonlethal
collective dose is administered to the biological matter. As
discussed above, with respect to inducing stasis in biological
matter that is not an entire organism, a "sublethal collective
dose" means an amount of multiple administrations of the active
compound that collectively is less than half of the amount of the
active compound that would cause at least a majority of cell(s) to
die within 24 hours of one of the administrations. In other
embodiments, an effective amount is characterized as a near-lethal
dose of the oxygen antagonist or other active compound. Likewise, a
"near lethal collective dose" means an amount of multiple
administrations of the oxygen antagonist or other active compound
that is within 25% of the amount of the active compound that would
cause at least a majority of cell(s) to die within 24 hours of the
one of the administrations. Also, a "supra-lethal collective dose"
means an amount of multiple administrations of the active compound
that is at least 1.5 times the amount of the active compound that
would cause at least a majority of cell(s) (or the entire organism)
to die within 24 hours of the one of the administrations. It is
contemplated that multiple doses can be administered so as to
induce stasis in the whole organism. The definition for "sub-lethal
collective dose," "near-lethal collective dose" and "supra-lethal
collective dose" can be extrapolated based on the individual doses
discussed earlier for stasis in whole organisms.
[0081] Biological matter may be exposed to or contacted with more
than one oxygen antagonist or other active compound. Biological
matter may be exposed to at least one active compound, including 2,
3, 4, 5, 6, 7, 8, 9, 10 or more oxygen antagonists or other active
compound, or any range derivable therein. With multiple active
compounds, the term "effective amount" refers to the collective
amount of active compounds. For example, the biological matter may
be exposed to a first active compound and then exposed to a second
active compound. Alternatively, biological matter may be exposed to
more than one active compound at the same time or in an overlapping
manner. Furthermore, it is contemplated that more than one active
compounds may be comprised or mixed together, such as in a single
composition to which biological matter is exposed. Therefore, it is
contemplated that, in some embodiments, a combination of active
compounds is employed in compositions, methods, and articles of
manufacture of the invention.
[0082] Biological matter may be provided with or exposed to an
active compound through inhalation, injection, catheterization,
immersion, lavage, perfusion, topical application, absorption,
adsorption, or oral administration. Moreover, biological matter may
be provided with or exposed to an active compound by administration
to the biological matter intravenously, intradermally,
intraarterially, intraperitoneally, intralesionally,
intracranially, intraarticularly, intraprostatically,
intrapleurally, intratracheally, intranasally, intrathecally,
intravitreally, intravaginally, intrarectally, topically,
intratumorally, intramuscularly, intraperitoneally, intraocularly,
subcutaneously, subconjunctival, intravesicularlly, mucosally,
intrapericardially, intraumbilically, intraocularally, orally,
topically, locally, by inhalation, by injection, by infusion, by
continuous infusion, by localized perfusion, via a catheter, or via
a lavage.
[0083] Methods and apparatuses of the invention involve a
protective agent that in some embodiments is an oxygen antagonist.
In still further embodiments, the oxygen antagonist is a reducing
agent. Additionally, the oxygen antagonist can be characterized as
a chalcogenide compound. It will be understood that active
compounds may also be protective agents. Moreover, any chalcogenide
compound can be considered an active compound so long as it
achieves a goal of the invention, regardless of whether it is an
oxygen antagonist.
[0084] In certain embodiments, the chalcogenide compound comprises
sulfur, while in others, it comprises selenium, tellurium, or
polonium. In certain embodiments, a chalcogenide compound contains
one or more exposed sulfide groups. It is contemplated that this
chalcogenide compounds contains 1, 2, 3, 4, 5, 6 or more exposed
sulfide groups, or any range derivable therein. In particular
embodiments, such a sulfide-containing compound is CS.sub.2 (carbon
disulfide).
[0085] Moreover, in some methods of the invention, stasis is
induced in cell(s) by exposing the cell(s) to a reducing agent that
has a chemical structure of (referred to as Formula I):
##STR00001##
[0086] wherein X is N, O, Po, S, Se, or Te;
[0087] wherein Y is N or O;
[0088] wherein R.sub.1 is H, C, lower alkyl, a lower alcohol, or
CN;
[0089] wherein R.sub.2 is H, C, lower alkyl, or a lower alcohol, or
CN;
[0090] wherein n is 0 or 1;
[0091] wherein m is 0 or 1;
[0092] wherein k is 0, 1, 2, 3, or 4; and,
[0093] wherein p is 1 or 2.
The terms "lower alkyl" and "lower alcohol" are used according to
their ordinary meanings and the symbols are the ones used to refer
to chemical elements. This chemical structure will be referred to
as the "reducing agent structure" and any compound having this
structure will be referred to as a reducing agent structure
compound. In additional embodiments, k is 0 in the reducing agent
structure. Moreover, in other embodiments, the R.sub.1 and/or
R.sub.2 groups can be an amine or lower alkyl amine. In others,
R.sub.1 and/or R.sub.2 could be a short chain alcohol or a short
chain ketone. Additionally, R.sub.1 and R.sub.2 may be a linear of
branched chain bridge and/or the compound may be a cyclic compound.
In still further embodiments, X may also be a halogen. The term
"lower" is meant to refer to 1, 2, 3, 4, 5, or 6 carbon atoms, or
any range derivable therein. Moreover, R.sub.1 and/or R.sub.2 may
be other small organic groups, including, C.sub.2-C.sub.5 esters,
amides, aldehydes, ketones, carboxylic acids, ethers, nitrites,
anhydrides, halides, acyl halides, sulfides, sulfones, sulfonic
acids, sulfoxides, and/or thiols. Such substitutions are clearly
contemplated with respect to R.sub.1 and/or R.sub.2. In certain
other embodiments, R.sub.1 and/or R.sub.2 may be short chain
versions of the small organic groups discussed above. "Short chain"
means 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon molecules, or
any range derivable therein.
[0094] It is contemplated that the reducing agent structure
compound can be a chalcogenide compound in some cases. In certain
embodiments, the chalcogenide compound has an alkyl chain with an
exposed chalcogenide. In others, the chalcogenide compound has a
chalcogenide that becomes exposed once it is taken up by the
biological matter. In this respect, the chalcogenide compound is
similar to a prodrug as an oxygen antagonist. Therefore, one or
more sulfur, selenium, oxygen, tellurium, polonium, or ununhexium
molecules on the compound becomes available subsequent to exposure
of the biological matter to the chalcogenide compound. In this
context, "available" means that the sulfur, selenide, oxygen,
tellurium, polonium, or ununhexium will retain a negative
charge.
[0095] In certain embodiments, the chalcogenide is a salt,
preferably salts wherein the chalcogen is in a -2 oxidation state.
Sulfide salts encompassed by embodiments of the invention include,
but are not limited to, sodium sulfide (Na.sub.2S), sodium hydrogen
sulfide (NaHS), potassium sulfide (K.sub.2S), potassium hydrogen
sulfide (KHS), lithium sulfide (Li.sub.2S), rubidium sulfide
(Rb.sub.2S), cesium sulfide (Cs.sub.2S), ammonium sulfide
((NH.sub.4).sub.2S), ammonium hydrogen sulfide (NH.sub.4)HS,
beryllium sulfide (BeS), magnesium sulfide (MgS), calcium sulfide
(CaS), strontium sulfide (SrS), barium sulfide (BaS), and the like.
In like fashion, embodiments of the present invention encompass,
but are not limited to, corresponding selenide and telluride salts.
It is specifically contemplated that the invention includes
compositions containing a chalcogenide salt (chalcogenide compound
that is a salt) with a pharmaceutically acceptable carrier or
prepared as a pharmaceutically acceptable formulation. In still
further embodiments, the reducing agent structure compound is
selected from the group consisting of H.sub.2S, H.sub.2Se,
H.sub.2Te, and H.sub.2Po. In some cases, the reducing agent
structure of Formula (I) has an X that is an S. In others, X is Se,
or X is Te, or X is Po, or X is O. Furthermore, k in the reducing
agent structure is 0 or 1 in some embodiments. In certain
embodiments, the reducing agent structure compound is
dimethylsulfoxide (DMSO), dimethylsulfide (DMS), carbon monoxide,
methylmercaptan (CH.sub.3SH), mercaptoethanol, thiocyanate,
hydrogen cyanide, methanethiol (MeSH), or CS.sub.2. In particular
embodiments, the oxygen antagonist is H.sub.2S, H.sub.2Se,
CS.sub.2, MeSH, or DMS. Compounds on the order of the size of these
molecules are particularly contemplated (that is, within 50% of the
average of their molecular weights).
[0096] In certain embodiments, a selenium-containing compound such
as H.sub.2Se is employed. The amount of H.sub.2Se may be in the
range of 1 to 1000 parts per billion in some embodiments of the
invention. It is further contemplated that any embodiment discussed
in the context of a sulfur-containing compound may be implemented
with a selenium-containing compound. This includes substituting one
of more sulfur atoms in a sulfur-containing molecule with a
corresponding selenium atom.
[0097] A further aspect of the invention encompasses compounds
represented by Formula IV:
##STR00002##
wherein: [0098] X is N, O, P, Po, S, Se, Te, O--O, Po--Po, S--S,
Se--Se, or Te--Te; [0099] n and m are independently 0 or 1; and
[0100] wherein R.sup.21 and R.sup.22 are independently hydrogen,
halo, cyano, phosphate, thio, alkyl, alkenyl, alkynyl, alkoxy,
aminoalkyl, cyanoalkyl, hydroxyalkyl, haloalkyl, hydroxyhaloalkyl,
alkylsulfonic acid, thiosulfonic acid, alkylthiosulfonic acid,
thioalkyl, alkylthio, alkylthioalkyl, alkylaryl, carbonyl,
alkylcarbonyl, haloalkylcarbonyl, alkylthiocarbonyl, aminocarbonyl,
aminothiocarbonyl, alkylaminothiocarbonyl, haloalkylcarbonyl,
alkoxycarbonyl, aminoalkylthio, hydroxyalkylthio, cycloalkyl,
cycloalkenyl, aryl, aryloxy, heteroaryloxy, heterocyclyl,
heterocyclyloxy, sulfonic acid, sulfonic alkyl ester, thiosulfate,
or sulfonamido; and [0101] Y is cyano, isocyano, amino, alkyl
amino, aminocarbonyl, aminocarbonyl alkyl, alkylcarbonylamino,
amidino, guanidine, hydrazino, hydrazide, hydroxyl, alkoxy,
aryloxy, hetroaryloxy, cyloalkyloxy, carbonyloxy, alkylcarbonyloxy,
haloakylcarbonyloxy, arylcarbonyloxy, carbonylperoxy,
alkylcarbonylperoxy, arylcarbonylperoxy, phosphate, alkylphosphate
esters, sulfonic acid, sulfonic alkyl ester, thiosulfate,
thiosulfenyl, sulfonamide, --R.sup.23R.sup.24, wherein R.sup.23 is
S, SS, Po, Po--Po, Se, Se--Se, Te, or Te--Te, and R.sup.24 is
defined as for R.sup.21 herein, or Y is administration of another
compound is initiated) in methods, compositions, and other articles
of manufacture of the invention to achieve the desired effects set
forth herein. In certain embodiments, more than one compound with
the structure of Formula I or Formula IV is provided. In certain
embodiments, multiple different compounds with a structure from the
same formula (i.e., Formula I or Formula IV) are employed, while in
other embodiments, when multiple different compounds are employed,
they are from different formulas.
[0102] In specific embodiments, it is contemplated that multiple
active compounds are used, wherein one of the compounds is carbon
dioxide (CO.sub.2). It is contemplated that at least one other
compound is also a Formula I and/or Formula IV compound in some
embodiments. In certain cases, carbon dioxide is provided to
biological matter in combination with H.sub.2S or an H.sub.2S
precursor (together, sequentially, or in an overlapping sequential
manner).
[0103] The amount of carbon dioxide to which the biological matter
may be exposed are about, at least about, or at most about, 2, 3,
4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
22, 23, 24, 25, 26, 27, 28, 29, 30% or more, or any range derivable
therein. In certain embodiments, the amount is expressed in terms
of ppm, such as about, at least about, or at most about 350, 400,
500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600,
1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
2800, 2900, 3000, 3100, 3200, 3300, 3400, 3500, 3600, 3700, 3800,
3900, 4000, 4100, 4200, 4300, 4400, 4500, 4600, 4700, 4800, 4900,
5000, 6000, 7000, 8000, 9000, 10000, 11000, 12000, 13000, 14000,
15000, 16000, 17000, 18000, 19000, 20000, 21000, 22000, 23000,
24000, 25000, 26000, 27000, 28000, 29000, 30000, 31000, 32000,
33000, 34000, 35000, 36000, 37000, 38000, 39000, 40000, 41000,
42000, 43000, 44000, 45000, 46000, 47000, 48000, 49000, 50000,
60000, 70000, 80000, 90000, 100000, 110000, 120000, 130000, 140000,
150000, 160000, 170000, 180000, 190000, 200000, 210000, 220000,
230000, 240000, 250000, 260000, 270000, 280000, 290000, 300000 or
more ppm, or any range derivable therein, as well as an molar
equivalents. It is contemplated that these concentrations could
apply to any other active compound in gaseous form.
[0104] In other embodiments, it is specifically contemplated that
the active compound is sodium sulfide, sodium thiomethoxide,
cysteamine, sodium thiocyanate, cysteamine-S--
##STR00003##
[0105] wherein X, R.sup.21 and R.sup.22, are as defined herein.
[0106] Moreover, it is contemplated that in some embodiments of the
invention, biological matter is provided with a precursor compound
that becomes the active version of the Formula I or IV compound by
exposure to biological matter, such as by chemical or enzymatic
means. In addition, the compound may be provided to the biological
matter as a salt of the compound, in the form of a free radical, or
a negatively charged, positively charged or multiply charged
species. Some compounds qualify as both a Formula I and a Formula
IV compound and in such cases, the use of the phrase "Formula I or
Formula IV" is not intended to connote the exclusion of such
compounds.
[0107] A compound identified by the structure of Formula I or
Formula IV may also, in certain embodiments, be characterized as an
oxygen antagonist, protective metabolic agent, or a precursor,
prodrug, or salt thereof. It is further contemplated that the
compound need not be characterized as such or qualify as such to be
a compound used in the invention, so long as it achieves a
particular method of the invention. In some other embodiments, the
compound may be considered a chalcogenide compound. It is
specifically contemplated that any compound identified by the
structure of Formula I or Formula IV or set forth in this
disclosure may be used instead of or in addition to an oxygen
antagonist in methods, compositions, and apparatuses of the
invention; similarly, any embodiments discussed with respect to any
of structure having Formula I or Formula IV or otherwise set forth
in this disclosure may be may be used instead of or in addition to
an oxygen antagonist. Moreover, any compound identified by the
structure of Formulas I or IV or set forth in this disclosure may
be combined with any oxygen antagonist or any other active compound
described herein. It is also contemplated that any combination of
such compounds may be provided or formulated together, sequentially
(overlapping or nonoverlapping), and/or in an overlapping
sequential manner (the administration of one compound is initiated
and before that is complete, phosphate sodium salt, or
tetrahydrothiopryan-4-ol. In additional embodiments, the active
compound is dimethylsulfoxide, thioacetic acid, selenourea,
2-(3-Aminopropyl)-aminoethanethiol-dihydrogen-phosphate-ester,
2-mercapto-ethanol, thioglycolicether, sodium selenide, sodium
methane sulfinate, thiourea, or dimethylsulfide. It is specifically
contemplated that these compounds, or any others discussed herein
including any compound with Formula I, II, III, or IV, may be
provided or administered to biological matter in an amount that is
about, at least about, or at most about 0.1, 0.2, 0.3, 0.4, 0.5,
0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,
66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,
83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,
100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,
113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,
126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,
139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151,
152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,
165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177,
178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190,
191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203,
204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216,
217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229,
230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242,
243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255,
256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268,
269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281,
282, 283, 284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294,
295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307,
308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320,
321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333,
334, 335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346,
347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359,
360, 361, 362, 363, 364, 365, 366, 367, 368, 369, 370, 371, 372,
373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384, 385,
386, 387, 388, 389, 390, 391, 392, 393, 394, 395, 396, 397, 398,
399, 400, 401, 402, 403, 404, 405, 406, 407, 408, 409, 410, 411,
412, 413, 414, 415, 416, 417, 418, 419, 420, 421, 422, 423, 424,
425, 426, 427, 428, 429, 430, 431, 432, 433, 434, 435, 436, 437,
438, 439, 440, 441, 442, 443, 444, 445, 446, 447, 448, 449, 450,
451, 452, 453, 454, 455, 456, 457, 458, 459, 460, 461, 462, 463,
464, 465, 466, 467, 468, 469, 470, 471, 472, 473, 474, 475, 476,
477, 478, 479, 480, 481, 482, 483, 484, 485, 486, 487, 488, 489,
490, 491, 492, 493, 494, 495, 496, 497, 498, 499, 500, 501, 502,
503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515,
516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528,
529, 530, 531, 532, 533, 534, 535, 536, 537, 538, 539, 540, 541,
542, 543, 544, 545, 546, 547, 548, 549, 550, 551, 552, 553, 554,
555, 556, 557, 558, 559, 560, 561, 562, 563, 564, 565, 566, 567,
568, 569, 570, 571, 572, 600, 700, 800, 900, 1000, 1100, 1200,
1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300,
2400, 2500, 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300, 3400,
3500, 3600, 3700, 3800, 3900, 4000, 4100, 4200, 4300, 4400, 4500,
4600, 4700, 4800, 4900, 5000, 5100, 5200, 5300, 5400, 5500, 5600,
5700, 5800, 5900, 6000, 6100, 6200, 6300, 6400, 6500, 6600, 6700,
6800, 6900, 7000, 7100, 7200, 7300, 7400, 7500, 7600, 7700, 7800,
7900, 8000, 8100, 8200, 8300, 8400, 8500, 8600, 8700, 8800, 8900,
9000, 9100, 9200, 9300, 9400, 9500, 9600, 9700, 9800, 9900, 10000
mM or mmol/kg (of biological matter), or any range derivable
therein.
[0108] It is specifically contemplated that any subset of active
compounds identified by name or structure may be used in methods,
compositions and articles of manufacture. It is also specifically
contemplated that any subset of these compounds may be disclaimed
as not constituting embodiments of the invention. The present
invention also concerns pharmaceutical compositions comprising a
therapeutically effective amount of one or more active compounds.
It is understood that such pharmaceutical compositions are
formulated in pharmaceutically acceptable compositions. For
example, the composition may include a pharmaceutically acceptable
diluent.
[0109] In certain embodiments, the pharmaceutical composition
contains an effective dose of an active to provide when
administered to a patient a Cmax or a steady state plasma
concentration of the active compound to produce a therapeutically
effective benefit. In certain embodiments, the Cmax or steady state
plasma concentration to be achieved is about, at least about, or at
most about 0.01, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,
31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64,
65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,
82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98,
99, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210,
220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340,
350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 441, 450, 460,
470, 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590,
600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720,
730, 740, 750, 760, 770, 780, 790, 800, 810, 820, 830, 840, 850,
860, 870, 880, 890, 900, 910, 920, 930, 940, 950, 960, 970, 980,
990, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900,
2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000 .mu.M or
more, or any range derivable therein. In certain embodiments, such
as with H.sub.2S, the desired Cmax or steady state plasma
concentration is about between 10 .mu.M to about 10 mM, or between
about 100 .mu.M to about 1 mM, or between about 200 .mu.M to about
800 .mu.M. Appropriate measures may be taken to consider and
evaluate levels of the compound already in the blood, such as
sulfur.
[0110] In certain embodiments, the pharmaceutical composition
provides an effective dose of H.sub.2S to provide when administered
to a patient a Cmax or a steady state plasma concentration of
between 10 .mu.M to 10 mM, between about 100 .mu.M to about 1 mM,
or between about 200 .mu.M to about 800 .mu.M. In relating dosing
of hydrogen sulfide to dosing with sulfide salts, in typical
embodiments, the dosing of the salt is based on administering
approximately the same sulfur equivalents as the dosing of the
H.sub.2S. Appropriate measures will be taken to consider and
evaluate levels of sulfur already in the blood.
[0111] In certain embodiments, the composition comprises a gaseous
form of one or more of the active compounds specified above. In
another embodiment, the composition comprises a salt of one or more
of these compounds. In one particular embodiment, a pharmaceutical
composition comprises a gaseous form of Formula I or IV or a salt
of Formula I or IV. A gaseous form or salt of H.sub.2S is
specifically contemplated in some aspects of the invention. It is
contemplated that the amount of gas to which biological matter is
provided is about, at least about, or at most about 5, 10, 15, 20,
25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140,
150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270,
280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400,
410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530,
540, 550, 560, 570, 580, 590, 600, 610, 620, 630, 640, 650, 660,
670, 680, 690, 700, 710, 720, 730, 740, 750, 760, 770, 780, 790,
800, 810, 820, 830, 840, 850, 860, 870, 880, 890, 900, 910, 920,
930, 940, 950, 960, 970, 980, 990, 1000, 1100, 1200, 1300, 1400,
1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300, 3400, 3500, 3600,
3700, 3800, 3900, 4000, 4100, 4200, 4300, 4400, 4500, 4600, 4700,
4800, 4900, 5000, 6000, 7000, 8000, 9000, 10000, 11000, 12000,
13000, 14000, 15000, 16000, 17000, 18000, 19000, 20000, 21000,
22000, 23000, 24000, 25000, 26000, 27000, 28000, 29000, 30000,
31000, 32000, 33000, 34000, 35000, 36000, 37000, 38000, 39000,
40000, 41000, 42000, 43000, 44000, 45000, 46000, 47000, 48000,
49000, 50000, 60000, 70000, 80000, 90000, 100000, 110000, 120000,
130000, 140000, 150000, 160000, 170000, 180000, 190000, 200000,
210000, 220000, 230000, 240000, 250000, 260000, 270000, 280000,
290000, 300000, 310000, 320000, 330000, 340000, 350000, 360000,
370000, 380000, 390000, 400000 or more ppm, or any range derivable
therein. Alternatively, the effective amount of gas(es) may be
expressed as about, at least about, or at most about 0.001, 0.002,
0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03,
0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6,
0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49,
50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,
67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83,
84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or
100%, or any range derivable therein, with respect to the
concentration in the air to which the biological matter is exposed.
Moreover, it is contemplated that with some embodiments, the amount
of gas to which biological matter is provided is about, at least
about, or at most about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60,
70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200,
210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330,
340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460,
470, 480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590,
600, 610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720,
730, 740, 750, 760, 770, 780, 790, 800, 810, 820, 830, 840, 850,
860, 870, 880, 890, 900, 910, 920, 930, 940, 950, 960, 970, 980,
990, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900,
2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700, 2800, 2900, 3000,
3100, 3200, 3300, 3400, 3500, 3600, 3700, 3800, 3900, 4000, 4100,
4200, 4300, 4400, 4500, 4600, 4700, 4800, 4900, 5000, 6000, 7000,
8000, 9000, 10000 parts per billion (ppb) or any range derivable
therein. In particular embodiments, the amount of hydrogen selenide
provided to biological matter is on this order of magnitude.
[0112] In some embodiments of the invention, the pharmaceutical
composition is a liquid. As discussed elsewhere, the composition
may be a liquid with the relevant compound(s) dissolved or bubbled
into the composition. In some cases, the pharmaceutical composition
is a medical gas. According to the United States Food and Drug
Administration, "medical gases" are those gases that are drugs
within the meaning of .sctn.201(g)(1) of the Federal Food, Drug and
Cosmetic Act ("the Act") (21 U.S.C. .sctn.321(g) and pursuant to
.sctn.503(b)(1)(A) of the Act (21 U.S.C. .sctn.353(b)(1)(A) are
required to be dispensed by prescription. As such, such medical
gases require an appropriate FDA label. A medical gas includes at
least one active compound.
[0113] The present invention further comprises apparatuses and
articles of manufacture comprising packaging material and,
contained within the packaging material, an active stasis compound,
wherein the packaging material comprises a label that indicates
that it can be used for inducing stasis in in vivo biological
matter.
[0114] In some embodiments, the apparatus or article of manufacture
further includes a pharmaceutically acceptable diluent. In
particular other embodiments, the apparatus or article of
manufacture has a buffering agent. The active compound is provided
in a first sealed container and the pharmaceutically acceptable
diluent is provided in a second sealed container. In other
embodiments, the device or article further has instructions for
mixing the active compound and the diluent. Additionally, the
active compound can be reconstituted for achieving any method of
the invention, such as for inducing stasis in in vivo biological
matter. It is contemplated that any label would specify the result
to be achieved and the use of the compound for patients in need of
that result.
[0115] The present invention also concerns an article of
manufacture comprising packed together: an active compound,
instructions for use of the active stasis compound, comprising: (a)
identifying in vivo tissue in need of stasis treatment; and (b)
administering an effective amount of the active compound to the in
vivo biological matter.
[0116] In further embodiments of the invention, there is an article
of manufacture comprising a medical gas including an active
compound and a label comprising details or use and administration
for inducing stasis in a biological matter or any other method of
the invention.
[0117] The present invention also concerns kits and methods of
using these kits. In some embodiments, there are kits for the
delivery of an active compound to a tissue site in need of stasis
treatment, or any other treatment of the claimed invention,
comprising: a drape adapted for forming a sealed envelope against a
tissue site; a container comprising an oxygen antagonist; and an
inlet in the drape, wherein the container comprising the active
compound is in communication with the inlet. In certain
embodiments, the kit includes an outlet in the drape wherein the
outlet is in communication with a negative pressure source. In some
cases, the drape comprises elastomeric material and/or has a
pressure sensitive adhesive covering the periphery of the drape.
The outlet may be placed in fluid communication with the negative
pressure source, which may or may not be a vacuum pump. There may
also be a flexible conduit communicating between the outlet and the
negative pressure source. In some embodiments, the kit includes a
canister, which may or may not be removable, in fluid communication
between the outlet and the negative pressure source. It is
contemplated that the container includes an active compound that is
in gaseous communication with the inlet. In certain embodiments,
the container includes an active compound that is a gas or a liquid
gas. The kit may also include a vaporizer in communication between
the container comprising an oxygen antagonist and the inlet. In
addition, it may have a return outlet in communication with the
container comprising the active compound.
[0118] In particular embodiments, the active compound in the kits
is carbon monoxide, carbon dioxide, H.sub.2Se, and/or H.sub.2S. In
certain embodiments, the tissue site for which the kit or method is
applied is wounded.
[0119] Moreover, it will be generally understood that any compound
discussed herein as an oxygen antagonist can be provided in prodrug
form to the biological matter, meaning that the biological matter
or other substance(s) in the environment of the biological matter
alters the prodrug into its active form, that is, into an oxygen
antagonist. It is contemplated that the term "precursor" covers
compounds that are considered "prodrugs."
[0120] The oxygen antagonist or other active compound may be or may
be provided as a gas, semi-solid liquid (such as a gel or paste),
liquid, or solid. It is contemplated that biological matter may be
exposed to more than one such active compound and/or to that active
compound in more than one state. Moreover, the active compound may
be formulated for a particular mode of administration, as is
discussed herein. In certain embodiments, the active compound is in
pharmaceutical acceptable formulation for intravenous delivery.
[0121] In certain embodiments, the active compound is a gas. In
particular embodiments, the gaseous active compound includes carbon
monoxide, carbon dioxide, nitrogen, sulfur, selenium, tellurium, or
polonium, or a mixture thereof. Moreover, it is specifically
contemplated that the active compound is a chalcogenide compound as
a gas. In some embodiments, the active compound is in a gas mixture
comprising more than one gas. The other gas(es) is a non-toxic
and/or a non-reactive gas in some embodiments. In some embodiments,
the other gas is a noble gas (helium, neon, argon, krypton, xenon,
radon, or ununoctium), nitrogen, nitrous oxide, hydrogen, or a
mixture thereof. For instance, the non-reactive gas may simply be a
mixture that constitutes "room air," which is a mixture of
nitrogen, oxygen, argon and carbon dioxide, as well as trace
amounts of other molecules such as neon, helium, methane, krypton,
and hydrogen. The precise amounts of each varies, though a typical
sample might contain about 78% nitrogen, 21% oxygen, 0.9% argon,
and 0.04% carbon dioxide. It is contemplated that in the context of
the present invention, "room air" is a mixture containing about 75
to about 81% nitrogen, about 18 to about 24% oxygen, about 0.7 to
about 1.1% argon, and about 0.02% to about 0.06% carbon dioxide. A
gaseous active compound may be first diluted with a non-toxic
and/or non-reactive gas prior to administration or exposure to
biological matter. Additionally or alternatively, any gaseous
active compound may be mixed with room air prior to administration
or exposure to biological matter or the compound may be
administered or exposed to the biological matter in room air.
[0122] In some instances, the gas mixture also contains oxygen. An
active compound gas is mixed with oxygen to form an oxygen gas
(O.sub.2) mixture in other embodiments of the invention.
Specifically contemplated is an oxygen gas mixture in which the
amount of oxygen in the oxygen gas mixture is less than the total
amount of all other gas or gases in the mixture.
[0123] In some embodiments, the active compound gas is carbon
monoxide and the amount of carbon monoxide is about the same or
exceeds any amount of oxygen in the oxygen gas mixture. In
particular embodiments, carbon monoxide is employed with blood-free
biological matter. The term "blood-free biological matter" refers
to cells and organs whose oxygenation is not dependent, or no
longer dependent, on the vasculature, such as an organ for
transplant. Preferably, the atmosphere will be 100% CO, but as will
be evident to one skilled in the art, the amount of CO may be
balanced with gases other than oxygen providing that the amount of
usable oxygen is reduced to a level that prevents cellular
respiration. In this context, the ratio of carbon
monoxide-to-oxygen is preferably 85:15 or greater, 199:1 or greater
or 399:1 or greater. In certain embodiments, the ratio is about, at
least about, or at most about 1:1, 2:1, 2.5:1, 3:1, 4:1, 5:1, 6:1,
7:1, 8:1, 9:1, 10:1, 15:1, 20:1, 25:1, 30:1. 35:1, 40:1, 45:1,
50:1, 55:1, 60:1, 65:1, 70:1, 75:1, 80:1, 85:1, 90:1, 95:1, 100:1,
110:1, 120:1, 130:1, 140:1, 150:1, 160:1, 170:1, 180:1, 190:1,
200:1, 210:1, 220:1, 230:1, 240:1, 250:1, 260:1, 270:1, 280:1,
290:1, 300:1, 310:1, 320:1, 330:1, 340:1, 350:1, 360:1, 370:1,
380:1, 390:1, 400:1, 410:1, 420:1, 430:1, 440:1, 450:1, 460:1,
470:1, 480:1, 490:1, 500:1 or more, or any range derivable
therein.
[0124] In still further embodiments, the above numbers pertain to
the ratio of carbon monoxide to a mixture of oxygen and one or more
other gases. In some cases, it is contemplated that the other gas
is a nonreactive gas such as nitrogen (N.sub.2). Thus, in other
embodiments of the invention, the above numbers apply to ratios of
carbon monoxide to a combination of oxygen and nitrogen
(O.sub.2/N.sub.2) that can be used in methods and apparatuses of
the invention. Accordingly, it will be understood that other gases
may or may not be present. In some embodiments, the CO:oxygen ratio
is balanced with one or more other gases (non-carbon monoxide and
non-oxygen gases). In particular embodiments, the CO:oxygen ratio
is balanced with nitrogen. In still further embodiments, the amount
of CO is a ratio of CO compared to room air, as is described by the
numbers above.
[0125] In some cases, the amount of carbon monoxide is relative to
the amount of oxygen, while in others, it is an absolute amount.
For example, in some embodiments of the invention, the amount of
oxygen is in terms of "parts per million (ppm)" which is a measure
of the parts in volume of oxygen in a million parts of air at
standard temperature and pressure of 20.degree. C. and one
atmosphere pressure and the balance of the gas volume is made up
with carbon monoxide. In this context, the amount of carbon
monoxide to oxygen is related in terms of parts per million of
oxygen balanced with carbon monoxide. It is contemplated that the
atmosphere to which the biological material is exposed or incubated
may be at least 0, 50, 100, 200, 300, 400, 500, 1000, or 2000 parts
per million (ppm) of oxygen balanced with carbon monoxide and in
some cases carbon monoxide mixed with a non-toxic and/or
non-reactive gas The term "environment" refers to the immediate
environment of the biological matter, that is, the environment with
which it is in direct contact. Thus, the biological material must
be directly exposed to carbon monoxide, and it is insufficient that
a sealed tank of carbon monoxide be in the same room as the
biological matter and be considered to be incubated an
"environment" according to the invention. Alternatively, the
atmosphere may be expressed in terms of kPa. It is generally
understood that 1 million parts=101 kPa at 1 atmosphere. In
embodiments of the invention, the environment in which a biological
material is incubated or exposed to is about, at least about, or at
most about 0.001, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07,
0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18,
0.19, 0.20. 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29,
0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80,
0.5, 0.90, 0.95, 1.0 kPa or more O.sub.2, or any range derivable
therein. As described above, such levels can be balanced with
carbon monoxide and/or other non-toxic and/or non-reactive gas(es)
Also, the atmosphere may be defined in terms of CO levels in kPa
units. In certain embodiments, the atmosphere is about, at least
about, or at most about 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50,
55, 60, 65, 70, 75, 80, 85, 90, 95, 101, 101.3 kPa CO, or any range
derivable therein. In particular embodiments, the partial pressure
is about or at least about 85, 90, 95, 101, 101.3 kPa CO, or any
range derivable therein.
[0126] The amount of time the sample is incubated or exposed to
carbon monoxide can also vary in embodiments of the invention. In
some embodiments, the sample is incubated or exposed to carbon
monoxide for about, for at least about, or for at most about 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60 or more minutes and/or, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours,
and/or 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more days.
[0127] In some embodiments, the invention concerns compositions and
articles of manufacture that contain one or more active compounds.
In certain embodiments, a composition has one or more of these
active compounds as a gas that is bubbled in it so that the
composition provides the compound to the biological matter when it
is exposed to the composition. Such compounds may be gels, liquids,
or other semi-solid material. In certain embodiments, a solution
has an oxygen antagonist as a gas bubbled through it. It is
contemplated that the amount bubbled in the gas will provide the
appropriate amount of the compound to biological material exposed
to the solution. In certain embodiments, the amount of gas bubbled
into the solution is about, at least about, or at most about 0.5,
1.0, 1.5, 2.0. 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0,
7.5, 8.0, 8.5, 9.0, 9.5, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100
times or more, or any range derivable therein, than the amount to
which the biological matter is effectively provided.
[0128] Biological matter is exposed to the gas in a closed
container in some embodiments of the invention. In some cases, the
closed container can maintain a particular environment or modulate
the environment as is desired. The environment refers to the amount
of oxygen antagonist that the biological matter is exposed and/or
the temperature, gas composition, or pressure of the environment.
In some cases, the biological matter is placed under a vacuum
before, during, or after exposure to an oxygen antagonist or other
active compound. Moreover, in other cases, the biological matter is
exposed to a normoxic environment after being exposed to an oxygen
antagonist or other active compound. In certain embodiments, the
present invention includes methods for inducing stasis or
protecting biological matter from injury or disease that include
providing an active compound to the biological matter in
combination with providing another stasis-inducing active compound
or environmental condition to the biological matter. Such
combination treatment may occur in any order, e.g., simultaneously
or sequentially. In certain embodiments, an active compound is
provided to biological matter, and the biological matter is
subsequently placed under hypoxic conditions, such as 5% O.sub.2,
or sequentially exposed to increasingly hypoxic conditions, such as
5% O.sub.2 followed by 4% O.sub.2, 3% O.sub.2, 2% O.sub.2, 1%
O.sub.2, or O.sub.2-free conditions, or any sequential combination
of such conditions.
[0129] Moreover, in other embodiments, the environment containing
the biological matter cycles at least once to a different amount or
concentration of the oxygen antagonist or other active compound,
wherein the difference in amount or concentration is by at least
one percentage difference. The environment may cycle back and forth
between one or more amounts or concentrations of the oxygen
antagonist or other active compound, or it may gradually increase
or decrease the amount or concentrations of an that compound. In
some cases, the different amount or concentration is between about
0 and 99.9% of the amount or concentration of the oxygen antagonist
or other active compound to which the biological matter was
initially exposed. It is contemplated that the difference in amount
and/or concentration is about, at least about, or at most about
0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75,
76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,
93, 94, 95, 96, 97, 98, 99% or more, or any range derivable
therein.
[0130] Methods of the invention can also include a step of
subjecting biological matter to a controlled temperature
environment. In certain embodiments, the biological matter is
exposed to a temperature that is a "nonphysiological temperature
environment," which refers to a temperature in which the biological
matter cannot live in for more than 96 hours. The controlled
temperature environment can have a temperature of about, at least
about, or at most about -210, -200, -190, -180, -170, -160, -150,
-140, -130, -120, -110, -100, -90, -80, -70, -60, -50, -40, -30,
-20, -10, -5, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49,
50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66,
67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83,
84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,
100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112,
113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125,
126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138,
139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151,
152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,
165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177,
178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190,
191, 192, 193, 194, 195, 196, 197, 198, 199, 200.degree. C. or
more, or any range derivable therein. Biological matter may also be
exposed to an oxygen antagonist or other active compound at room
temperature, which means a temperature between about 20.degree. C.
and about 25.degree. C. Furthermore, it is contemplated the
biological matter achieves a core temperature of any amount or
range of amounts discussed.
[0131] It is contemplated that the biological matter can be
subjected to a nonphysiological temperature environment or a
controlled temperature environment before, during or after exposure
to the oxygen antagonist(s) or other active compound(s).
Furthermore, in some embodiments, the biological matter is
subjected to a nonphysiological temperature environment or a
controlled temperature environment for a period of time between
about one minute and about one year. The amount of time may be
about, at least about, or at most about 30 seconds, 1, 2, 3, 4, 5,
10, 15, 20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more years, and any
combination or range derivable therein. Moreover, there may also be
a step of increasing the ambient temperature relative to the
reduced temperature.
[0132] Moreover, it is contemplated that the temperature may be
altered or cycled during the process in which temperature is
controlled. In some embodiments, the temperature of the biological
matter may first be reduced before it is placed in the environment
that has the oxygen antagonist or other active compound, while in
others, the biological matter may be cooled by placing it in the
environment with the active compound, that is below the temperature
of the biological matter. The biological matter and/or environment
may be cooled or heated gradually, such that the temperature of the
biological matter or environment starts at one temperature but then
reaches another temperature.
[0133] Methods of the invention can also include a step of
subjecting biological matter to a controlled pressure environment.
In certain embodiments, the biological matter is exposed to
pressure that is lower than the pressure under which the organism
is typically under. In certain embodiments, the biological matter
is subjected to a "nonphysiological pressure environment," which
refers to a pressure under which the biological matter cannot live
under for more than 96 hours. The controlled pressure environment
can have a pressure of about, at least about, or at most
10.sup.-14, 10.sup.-13, 10.sup.-12, 10.sup.-11, 10.sup.-10,
10.sup.-9, 10.sup.-8, 10.sup.-7, 10.sup.-6, 10.sup.-5, 10.sup.-4,
10.sup.-3, 10.sup.-2, 10.sup.-1, 0.2, 0.3, 0.4 or 0.5 atm or more,
or any range derivable therein.
[0134] It is contemplated that the biological matter can be
subjected to a nonphysiological pressure environment or a
controlled pressure environment before, during or after exposure to
the active compound(s). Furthermore, in some embodiments, the
biological matter is subjected to a nonphysiological pressure
environment or a controlled pressure environment for a period of
time between about one minute and about one year. The amount of
time may be about, at least about, or at most about 30 seconds, 1,
2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2,
3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24 hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5
weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 months, 1, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more
years, and any combination or range derivable therein.
[0135] Moreover, it is contemplated that the pressure may be
altered or cycled during the process in which pressure is
controlled. In some embodiments, the pressure to which the
biological matter is exposed may first be reduced before it is
placed in the environment that has the active compound, while in
others, the biological matter placed under pressure after exposure
to an active compound. The pressure may be reduced gradually, such
that the pressure of the environment starts at one pressure but
then reaches another pressure within 10, 20, 30, 40, 50, 60
seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55
minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24 hours, and/or 1, 2, 3, 4, 5, 6, 7 days
or more, and any combination or range derivable therein. In certain
embodiments, methods include modulating environmental oxygen levels
or removing the biological material from an environment having
oxygen. Operationally, exposing biological material to an
environment in which oxygen is diminished or absent may mimic
exposure of the biological material to an oxygen antagonist. It is
contemplated that in some embodiments of the invention, biological
matter is exposed to or provided with an active compound under
conditions in which the environment of the biological matter is
hypoxic or anoxic, as described in further detail below. This may
be intentional or nonintentional. Thus, in some embodiments of the
invention, biological matter is intentionally placed in an
environment that is anoxic or hypoxic or in an environment that is
made anoxic or hypoxic. In other embodiments, the biological matter
is under such conditions as a result of an unintended situation,
for example, if the biological matter is under ischemic or
potentially ischemic conditions. Therefore, it is contemplated in
some cases that the hypoxic or anoxic conditions would damage the
matter in the absence of the active compound.
[0136] In certain methods of the invention, there also is a step of
assessing the level of the oxygen antagonist and/or oxidative
phosphorylation in the biological matter in which stasis was
induced. Moreover, in some embodiments of the invention, there is a
step of assessing the level of cellular metabolism that is
generally occurring in the biological matter. In some cases, the
amount of the active compound in the biological matter is measured
and/or a reduction in the temperature of the biological matter is
assessed. Moreover, in some methods of the invention, the extent of
one or more therapeutic effects is evaluated.
[0137] In certain other embodiments, any toxicity effect on the
biological matter from an active compound and/or environmental
change (temperature, pressure) is monitored or controlled for. It
is contemplated that toxicity can be controlled for by altering the
level, amount, duration, or frequency of an active compound and/or
environmental change to which the biological matter is exposed. In
certain embodiments the alteration is a reduction, while in certain
other embodiments, the alteration is an increase. It is
contemplated that the skilled artisan is aware of a number of ways
of evaluating toxicity effects in biological matter.
[0138] Other optional steps for methods of the invention include
identifying an appropriate active compound; diagnosing the patient;
taking a patient history and/or having one or more tests done on
the patient prior to administering or prescribing an active
compound to the patient.
[0139] Compositions, methods, and articles of manufacture of the
invention can be used on biological matter that will be transferred
back into the donor organism from which it was derived (autologous)
or a different recipient (heterologous) subject. In some
embodiments, biological matter is obtained directly from a donor
organism. In others, the biological matter is placed in culture
prior to exposure to an oxygen antagonist or other active compound.
In some situations, the biological matter is obtained from a donor
organism administered extracorporeal membrane oxygenation prior to
retrieval of the biological matter, which is a technique
implemented to aid in the preservation of biological matter.
Moreover, methods include administering or implanting the
biological matter in which stasis was induced to a live recipient
organism.
[0140] Methods of the invention also concern inducing stasis in in
vivo biological matter comprising incubating the biological matter
with an oxygen antagonist or other active compound that creates
hypoxic conditions for an effective amount of time for the
biological matter to enter stasis.
[0141] Furthermore, other embodiments of the invention include
methods of reducing oxygen demand in in vivo biological matter
comprising contacting the biological matter with an effective
amount of an oxygen antagonist or other active compound to reduce
their oxygen demand. It is contemplated that oxygen demand is
reduced about, at least about, or at most about 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
92, 93, 94, 95, 96, 97, 98, 99, or 100%, or any range derivable
therein, with respect to the amount of oxygen demand in cells of
the biological matter or a representative sample of cells from the
biological matter not exposed or no longer exposed to the oxygen
antagonist or other active compound.
[0142] Other aspects of the invention concern methods for
preserving in vivo biological matter comprising exposing the in
vivo biological matter to an effective amount of an oxygen
antagonist or other active compound to preserve the biological
matter in vivo.
[0143] The present invention also concerns a method of delaying or
reducing the effects of trauma on or in an organism comprising
exposing biological matter at risk for trauma to an effective
amount of an oxygen antagonist or other active compound.
[0144] In other aspects of the invention, there are methods for
treating or preventing hemorrhagic shock in a patient comprising
exposing the patient to an effective amount of an oxygen antagonist
or other active compound. Alternatively, in some embodiments
methods prevents lethality in the patient as a result of the
bleeding and/or hemorrhagic shock. In such methods of preventing a
patient from bleeding to death or prevent lethality in a bleeding
patient, steps include exposing the patient to an effective amount
of an oxygen antagonist or other active compound. In certain
embodiments, the oxygen antagonist is specifically contemplated to
be a chalcogenide compound such as H.sub.2S.
[0145] Methods for reducing heart rate in an organism are also
included as part of the invention. Such methods involve contacting
the biological sample or organism with an effective amount of an
oxygen antagonist or other active compound.
[0146] One embodiment of the invention relates to a method of
inducing hibernation in a mammal comprising contacting the mammal
with an effective amount of an oxygen antagonist or other active
compound.
[0147] In another embodiment, there is a method of anesthetizing an
organism comprising exposing biological matter in which anesthesia
is desired to an effective amount of an oxygen antagonist or other
active compound. It is contemplated that the anesthesia may be
similar to local or general anesthesia.
[0148] The present invention further includes methods of protecting
a mammal from radiation therapy or chemotherapy comprising
contacting the mammal with an effective amount of an oxygen
antagonist or other active compound prior to or during radiation
therapy or chemotherapy. With local administration of the cancer
therapy, it is specifically contemplated that the oxygen antagonist
or other active compound may also be administered locally to the
affected organ, tissue, and/or cells. In certain embodiments,
methods can be used for preventing or reducing hair loss in a
chemotherapy patient. It is contemplated that such a patient may
have already received chemotherapy or be a candidate for
chemotherapy. In particular cases, it is contemplated that an
active compound is provided to the patient as a topical gel to be
applied where the hair loss is anticipated or present.
[0149] The present invention also covers reducing the oxygen
requirement of biological matter, meaning that the amount of oxygen
required by the biological matter to survive is reduced. This can
be achieved by providing an effective amount of one or more active
compounds. It is generally known how much oxygen particular
biological matter require to survive, which can also be dependent
on time, pressure, and temperature. In certain embodiments of the
invention, the oxygen requirement of the biological matter is
reduced by about, at least about, or at most about 1, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
92, 93, 94, 95, 96, 97, 98, 99, 100%, or any range derivable
therein, as compared to the requirement of the biological matter in
the absence of the effective amount of the active compound(s).
[0150] In additional embodiments, there are methods of treating a
hyperproliferative disease (e.g., cancer) in a mammal comprising
contacting the mammal with an effective amount of an oxygen
antagonist or other active compound and subjecting the mammal to
hyperthermia therapy.
[0151] While methods of the invention may be applied to preserving
organs for transplant, other aspects of the invention concern the
recipient organism. In some embodiments, there are methods of
inhibiting rejection of an organ transplant in a mammal comprising
providing the mammal with an effective amount of an oxygen
antagonist or other active compound.
[0152] Temperature regulation can be achieved in organisms by
employing oxygen antagonists or other active compounds. In some
embodiments, there is a method of treating a subject with
hypothermia comprising (a) contacting the subject with an effective
amount of an oxygen antagonist, and then (b) subjecting the subject
to an environmental temperature above that of the subject. In other
embodiments, the present invention includes a method of treating a
subject with hyperthermia comprising (a) contacting the subject
with an effective amount of an oxygen antagonist or other active
compound. In some cases, treatment of hyperthermia also includes
(b) subjecting the subject to an environmental temperature that is
at least about 20.degree. C. below that of the subject. As
discussed above, exposing the subject to nonphysiological or a
controlled temperature environment can be used in additional
embodiments. It is contemplated that this method may be achieved
with active compounds generally.
[0153] In some cases, the invention concerns a method for inducing
cardioplegia in a patient undergoing bypass surgery comprising
administering to the patient an effective amount of an oxygen
antagonist or other active compound. It is contemplated that
administration may be local to the heart so as to protect it.
[0154] Other aspects of the invention relate to a method for
preventing hematologic shock in a patient comprising administering
to the patient an effective amount of an oxygen antagonist or other
active compound.
[0155] Moreover, there are methods for promoting wound healing in
an organism comprising administering to the organism or wound an
effective amount of an oxygen antagonist or other active
compound.
[0156] In addition, the present invention covers a method for
preventing or treating neurodegeneration in a mammal comprising
administering to the mammal an effective amount of an oxygen
antagonist or other active compound.
[0157] The present invention also covers reducing the oxygen
requirement of biological matter, meaning that the amount of oxygen
required by the biological matter to survive is reduced. This can
be achieved by providing an effective amount of one or more active
compounds. It is generally known how much oxygen particular
biological matter require to survive, which can also be dependent
on time, pressure, and temperature. In certain embodiments of the
invention, the oxygen requirement of the biological matter is
reduced by about, at least about, or at most about 1, 2, 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
92, 93, 94, 95, 96, 97, 98, 99, 100%, or any range derivable
therein, as compared to the requirement of the biological matter in
the absence of the effective amount of the active compound(s).
[0158] Additional embodiments of the invention concern methods for
preventing hair loss, such as from chemotherapy, by administering
to a patient who has or will undergo chemotherapy an effective
amount of at least one active compound.
[0159] In cases in which biological matter is being protected from
damage or further damage, it is contemplated that the biological
matter may be exposed to an oxygen antagonist within about, within
at least about, or within at most about 30 seconds, 1, 2, 3, 4, 5,
10, 15, 20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more years, and any
combination or range derivable therein, after initial damage
(trauma or wound or degeneration) occurs. Thus in additional
embodiments of the invention, methods include an initial assessment
of any damage, trauma, a wound, or degeneration.
[0160] In certain embodiments of the invention there are methods
for treating a patient affected with a hematological disorder,
which means a disease, disorder or condition that affects any
hematopoietic cells or tissue. Examples include sickle cell disease
and thalassemia. Thus, in some embodiments, there are methods of
treating a patient with sickle cell disease or thalassemia with an
effective amount of an active compound. In other embodiments, there
are methods for enhancing survivability in a patient with cystic
fibrosis (CF) by administering or providing an effective amount of
an active compound. In other methods of the invention, there are
methods for treating cynanide poisoning in a subject comprising
administering an effective amount of an active compound. In certain
embodiments, the compound is H.sub.2S.
[0161] Other aspects of the invention concern methods for
preserving one or more cells that are separate from an organism
comprising contacting the cell(s) with an effective amount of an
oxygen antagonist or other active compound to preserve the one or
more cells. In addition to the cells and cell types discussed above
and elsewhere in this application, it is contemplated that shrimp
embryos are specifically contemplated for use with the present
invention.
[0162] Moreover, in some embodiments of the invention, there are
methods for preserving platelets. Shortcomings of the prior art are
reduced or eliminated using techniques of this disclosure.
Embodiments concerning platelets and oxygen reduction find wide
application including but not limited to any application that would
benefit from longer-lasting storage of platelets.
[0163] In one embodiment, oxygen reduction techniques can be
embodied in a kit. For example, the kit currently sold under
product number 261215, available from Becton Dickinson, makes use
of select techniques described here. That kit includes an anaerobic
generator (e.g., a hydrogen gas generator), Palladium Catalysts, an
anaerobic indicator, and a gas impermeable, sealable, "BioBag" into
which the above components (together with platelets in a
gas-permeable bag) are placed and sealed.
[0164] In other embodiments of the invention, there are methods for
reversibly inhibiting metabolism of a cell and/or organism by
providing an effective amount of an active compound. It is
specifically contemplated that rotenone is not the compound
employed in this method, or possibly other methods of the
invention. Moreover, it is also contemplated that in some
embodiments, rotenone is excluded as an active compound. Similarly,
it is contemplated that nitric oxide may be excluded as an active
compound.
[0165] In other embodiments of the invention, methods are provided
for enhancing the ability of biological matter to enter stasis in
response to an injury or disease by providing an effective amount
of an active compound, thereby protecting the biological matter
from damage or injury, thereby enhancing survival of biological
matter. Related embodiments include methods of preparing or priming
biological matter for entry into stasis in response to an injury or
disease by providing an effective amount of an active compound.
Other related embodiments include method of inducing biological
matter into pre-stasis, thereby protecting the biological matter
from damage or injury. For example, treatment with an active
compound at a dosage or for a time less than required to induce
stasis enables the biological matter to more readily or more
completely achieve a beneficial state of stasis in response to an
injury or disease, while in the absence of treatment with the
active compound, the biological matter would die or suffer damage
or injury before it reached a protective level of stasis, e.g., a
level sufficient to render the biological matter resistant to
lethal hypoxia.
[0166] Certain injuries and disease states cause biological matter
to reduce its metabolism and/or temperature to degrees that may not
achieve stasis. For example, hypoxia, ischemia, and blood loss all
reduce the amount of oxygen available and supplied to oxygen
utilizing biological matter, thereby reducing oxygen utilization in
cells of the biological matter, reducing energy production derived
from oxidative phosphorylation, and thereby decreasing
thermogenesis, leading to hypothermia. Depending on the severity or
time elapsed following the onset or progression of the injurious or
disease insult, "stasis" may or may not have been achieved.
Treatment with an active compound lowers the threshold (i.e., the
severity or duration of the insult that is needed to achieve
stasis) for induction of stasis, or it may add to or synergize with
the injurious or disease stimuli to induce stasis in biological
matter under injurious conditions that would not have resulted in
stasis were it not for the active compound treatment. Such activity
of active compounds is determined by comparing the stasis-inducing
effects (magnitude, kinetics) of injurious or disease stimuli alone
with those in which the biological matter was pre-exposed, exposed
concomitantly, exposed after, or any combination thereof, to the
active compound. For example, as described in Example 11 of the
instant patent application, pre-exposure of mice to 150 ppm
H.sub.2S in air caused an approximately two-fold drop in CO.sub.2
production prior to exposure to hypoxia (5% O.sub.2). Subsequently,
CO.sub.2 production in pre-treated mice fell approximately 50-fold
during hypoxia. In contrast, while CO.sub.2 production in control,
H.sub.2S untreated mice also fell, the hypoxia survivability of the
mice was not achieved, presumably since the mice died before stasis
was achieved.
[0167] In other aspects of the invention, there are methods for
inducing sleep in an organism comprising exposing the organism to
an effective amount of an active compound, wherein the effective
amount is less than an amount that can induce stasis in the
organism. The term "sleep" is used according to its ordinary and
plain meaning in a medical context. Sleep is distinguishable from
other states of unconsciousness, which are also contemplated as
states that can be achieved using methods of the invention.
[0168] The present invention also concerns methods for
anesthetizing biological matter comprising exposing the matter to
an effective amount of an active compound, wherein the effective
amount is less than an amount that can induce stasis in the
organism.
[0169] In the methods discussed above, an effective amount that is
less than an amount that can induce stasis in an organism may be
reduced with respect to duration and/or amount. That reduction may
be a reduction in amount by 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46,
47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80,
81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,
98, 99 percent, or any range derivable therein, of the amount to
induce stasis. A reduction may be a reduction in duration (length
of exposure time) by 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30,
35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3, 4,
5, 6, 7, days, 1, 2, 3, 4, 5 weeks, and/or 1, 2, 3, 4, 5, 6, 7, 8,
9, 10, 11, 12 months, or any range derivable therein.
Alternatively, the reduction may be in terms of the overall
effective amount provided to the biological matter, which may be a
reduction of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67,
68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,
85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99 percent,
or any range derivable therein, relative to the overall effective
amount to induce stasis in an organism of that species and/or
size.
[0170] It is specifically contemplated that the present invention
can be used for preserving organisms that are used for consumption
or laboratory research, such as flies, frogs, fish, mice, rats,
dogs, shrimp, and embryos thereof.
[0171] Methods of the invention can involve employing an apparatus
or system that maintains the environment in which biological matter
is placed or exposed to. The invention includes an apparatus in
which an oxygen antagonist or other active compound, particularly
as a gas, is supplied. In some embodiments, the apparatus includes
a container with a sample chamber for holding the biological
matter, wherein the container is connected to a supply of gas
comprising the oxygen antagonist(s). It is specifically
contemplated that the container may be a solid container or it may
flexible, such as a bag.
[0172] In some embodiments, the invention is an apparatus for
preserving cell(s), the apparatus comprising: a container having a
sample chamber with a volume of no greater than 775 liters; and a
first gas supply in fluid communication with the sample chamber,
the first gas supply including carbon monoxide. In further
embodiments, the apparatus also includes a cooling unit that
regulates the temperature inside the sample chamber and/or a gas
regulator that regulates the amount of oxygen antagonist or other
active compound in the chamber or the amount of oxygen antagonist
or other active compound in a solution that is in the chamber.
[0173] It is contemplated that there may be a gas supply for a
second or additional gas or a second or additional gas supply for
the oxygen antagonist or other active compound. The second gas
supply may be connected with the sample chamber or it may be
connected with the first gas supply. The additional gas, as
discussed above, may be a non-toxic and/or non-reactive gas.
[0174] A gas regulator is part of the apparatus in some embodiments
of the invention. One, two, three, or more gas regulators may be
employed. In some cases, the gas regulator regulates the gas
supplied to the sample chamber from the first gas supply.
Alternatively, it regulates the gas supplied to the sample chamber
or first gas supply from the second gas supply, or there may be a
regulator for both the first and second gas supplies. It is further
contemplated that any gas regulator can be programmed to control
the amount of gas supplied to the sample chamber and/or to another
gas supply. The regulation may or may not be for a specified period
of time. There may be a gas regulator, which may or may not be
programmable, for any gas supply directly or indirectly connected
to the sample chamber. In some cases, the gas regulator is
electronically programmable.
[0175] In some cases, the pressure and/or the temperature inside
the chamber can be regulated with either a pressure regulator or
temperature regulator, respectively. As with the gas regulator,
these regulators may be electronically programmable. The apparatus
of the invention may also have a cooling and/or heating unit to
achieve the temperatures discussed above. The unit may or may not
be electronically programmable.
[0176] In additional embodiments, the apparatus includes a wheeled
cart on which the container rests or it may have one or more
handles.
[0177] It is specifically contemplated that the invention includes
an apparatus for cell(s), tissues, organs, and even whole
organisms, in which the apparatus has: a container having a sample
chamber; a first gas supply in fluid communication with the sample
chamber, the first gas supply including the oxygen antagonist(s) or
other active compound(s); and an electronically-programmable gas
regulator that regulates gas supplied to the sample chamber from
the first gas supply.
[0178] In some embodiments, the apparatus also has a structure
configured to provide a vacuum within the sample chamber.
[0179] Moreover, any oxygen antagonist or other active compound
described in this application is contemplated for use with
apparatuses of the invention. In specific embodiments, carbon
monoxide can be administered using this apparatus. In other cases,
a chalcogenide compound can be administered or a compound having
the reducing agent structure. In still further embodiments, an
active compound is administered using the apparatus. In specific
embodiments, the invention covers a device or its use. In certain
embodiments, the device is single dose delivery device. In other
embodiments, the device is an inhaler or nebulizer. In even further
embodiments, other devices include, but are not limited to, an
injection device such as a pen, a pump such as an infusion pump, or
a patch. Moreover, it is contemplated that these devices may or may
not be single dose delivery devices.
[0180] Additionally, the present invention concerns screening
assays. In some embodiments, a candidate substance is screened for
the ability to act as an oxygen antagonist or active compound,
specifically including a protective metabolic agent. This can be
done using any assay described herein, such as by measuring carbon
dioxide output. Any substance identified as having exhibiting
characteristics of an oxygen antagonist or other active compound
can be further characterized or tested. Moreover, it is
contemplated that such a substance can be administered to
biological matter to induce stasis or manufactured thereafter.
[0181] In certain embodiments, there are screening methods for
active compounds, including active stasis compounds. Furthermore,
the methods of screening may be for oxygen antagonists or for any
other compounds that can effect the methods discussed herein. In
some embodiments, there are screening methods involving a) exposing
a zebrafish embryo to a substance; b) measuring the heart rate of
the embryo; c) comparing the heart rate of the embryo in the
presence of the substance to the heart rate in the absence of the
substance, wherein a reduction of heart rate, such as by 50% or
more, identifies the substance as a candidate active compound.
Instead of zebrafish embryos, it is contemplated that other
non-human organisms may be used as well, such as fish, frogs,
flies, shrimp, or their embryos. In further embodiments, the heart
rate of the embryo is measured by counting the number of
heartbeats. This can be done, in some cases, by viewing the embryo
under a dissecting microscope.
[0182] Other screening embodiments involve: a) exposing a nematode
to a substance; b) assaying one or more of the following cellular
respiration factors: i) core body temperature; ii) oxygen
consumption; iii) motility; or, iv) carbon dioxide production; c)
comparing the cellular respiration factor of the nematode in the
presence of the substance to the cellular respiration factor in the
absence of the substance, wherein a reduction of the characteristic
identifies the substance as a candidate active compound. It is
specifically contemplated that motility of the nematodes is assayed
in some methods of the invention.
[0183] In some embodiments, the methods first involve identifying
an appropriate substance to screen. In certain embodiments, the
substance will be a chalcogenide, reducing agent, or have the
structure of Formula I or Formula IV, or any other compound
discussed herein.
[0184] It is further contemplated that subsequent screens can be
done in organisms considered higher or more complex than those used
in preliminary or initial screens. Thus, it is contemplated that
one or more cellular respiration factors will be assayed in these
other organisms to further evaluate a candidate compound. In
certain embodiments, subsequent screens involve the use of mice,
rats, dogs, etc.
[0185] It is contemplated that a number of different organisms or
biological matter (other cells or tissues) could be used and a
number of different cellular respiration factors could be assayed
in screening methods of the invention. In addition, it is
contemplated that multiple such screens are performed at the same
time in some embodiments of the invention.
[0186] It will of course be understood that in order for the
substance to be considered a candidate active compound (or oxygen
antagonist, or stasis inducer or protective metabolic agent, etc.)
the substance must not kill the organism or cells in the assay and
the effect must be reversible (that is, the characteristic that is
altered needs to resume to its level before the exposure to the
substance).
[0187] It is of course understood that any method of treatment can
be used in the context of a preparation of a medicament for the
treatment of or protection against the specified disease or
condition. This includes, but is not limited to, the preparation of
a medicament for the treatment of hemorrhagic or hematologic shock,
wounds and tissue damage, hyperthermia, hypothermia,
neurodegeneration, sepsis, cancer, and trauma. Moreover, the
invention includes, but is not limited to, the preparation of a
medicament for a treatment to prevent death, shock, trauma, organ
or tissue rejection, damage from cancer therapy, neurodegeneration,
and wound or tissue damage.
[0188] As discussed above, organismal stasis is not any of the
following states: sleep, comatose, death, anesthetized, or grand
mal seizure. However, it is contemplated in some embodiments of the
invention, that such states are the desired goal of employing
methods, compositions and articles of manufacture of the invention.
Any embodiment discussed with respect to one aspect of the
invention applies to other aspects of the invention as well.
Moreover, embodiments may be combined.
[0189] Any embodiment involving "exposing" biological matter to an
active compound may also be implemented so that biological matter
is provided with the active compound or administered the active
compound. The term "provide" is used according to its ordinary and
plain meaning: "to supply or furnish for use" (Oxford English
Dictionary), which, in the case of patients, may refer to the
action performed by a doctor or other medical personnel who
prescribes a particular active compound or administers it directly
to the patient.
[0190] The embodiments in the Example section are understood to be
embodiments of the invention that are applicable to all aspects of
the invention.
[0191] The use of the term "or" in the claims is used to mean
"and/or" unless explicitly indicated to refer to alternatives only
or the alternatives are mutually exclusive, although the disclosure
supports a definition that refers to only alternatives and
"and/or."
[0192] Throughout this application, the term "about" is used to
indicate that a value includes the standard deviation of error for
the device or method being employed to determine the value. In any
embodiment discussed in the context of a numerical value used in
conjunction with the term "about," it is specifically contemplated
that the term about can be omitted.
[0193] Following long-standing patent law, the words "a" and "an,"
when used in conjunction with the word "comprising" in the claims
or specification, denotes one or more, unless specifically
noted.
[0194] Other objects, features and advantages of the present
invention will become apparent from the following detailed
description. It should be understood, however, that the detailed
description and the specific examples, while indicating specific
embodiments of the invention, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the invention will become apparent to those skilled in the
art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0195] The following drawings form part of the present
specification and are included to further demonstrate certain
aspects of the present invention. The invention may be better
understood by reference to one or more of these drawings in
combination with the detailed description of specific embodiments
presented herein.
[0196] FIG. 1 Human keratinocytes survive exposure to 100% CO.
Cells were inspected visually using an inverted phase contrast
microscope. Quantitation of the number of viable keratinocytes as
judged by trypan blue staining, which is an indicator of cell
death.
[0197] FIG. 2 Discontinuity of survivability in hypoxia.
Viabilities to adulthood were assayed following exposure to 24
hours of anoxia (pure N.sub.2), intermediate hypoxia (0.01 kPa
O.sub.2, 0.05 kPa O.sub.2 or 0.1 kPa O.sub.2) or mild hypoxia (0.5
kPa O.sub.2) in wild-type embryos. All data points are the result
of at least 3 independent experiments and worms that could not be
accounted for were dropped from the total.
[0198] FIG. 3 Carbon monoxide protects against hypoxia. Viabilities
to adulthood were assayed following exposure to 24 hours of pure
carbon monoxide, 0.05 kPa O.sub.2/N.sub.2 or 0.05 kPa O.sub.2/CO in
wild-type embryos. All data points are the result of at least 3
independent experiments and worms that could not be accounted for
were dropped from the total.
[0199] FIG. 4A Metabolic rate decreases before body core
temperature when mice are exposed to hydrogen sulfide. Exposure of
mice to 80 ppm (at 0 minutes on the X axis) results in an
approximately 3-fold decrease in CO.sub.2 production (black line)
in less than five minutes. This precedes the drop in core
temperature of the animal toward the ambient temperature (gray
line).
[0200] FIG. 4B Temperature of mice exposed to hydrogen sulfide.
Each trace represents a continuous measurement of core body
temperature in individual mouse exposed to either 80 ppm of
H.sub.2S, or to room air. Numbers on the vertical axis are
temperature in .degree. Celsius. On the horizontal axis, the
numbers reflect time in hours. The experiments were carried out for
6 hours followed by recordings of the recovery. The beginning point
is at 1:00, and the end of the 6 hr treatment is about 7:00.
[0201] FIG. 5 Exposure to 80 ppm hydrogen sulfide causes the core
body temperature of a mouse to approach ambient temperature. Gas
was turned on and temperature decreased starting at time 0:00.
Atmosphere switched back to room air at time 6:00. Triangles
indicate the core body temperature of the mouse as determined by
radiotelemetry. This was approximately 39.degree. C. at time 0:00.
Diamonds indicate the ambient temperature which was reduced from
23.degree. C. to 13.degree. C. in the first 3 hours of the
experiment, and then increased again toward 23.degree. C. from hour
6:00 stabilizing at around hour 9:00.
[0202] FIG. 6 The rate of body core temperature drop is dependent
upon the concentration of hydrogen sulfide given to the mice. All
lines represent core body temperature of a single mouse as
determined by radiotelemetry. Mice subjected to 20 ppm and 40 ppm
H.sub.2S exhibit minor drops in core temperature. Exposure to 60
ppm induced a substantial drop in temperature beginning at
approximately hour 4:00. The mouse exposed to 80 ppm exhibited a
substantial drop in temperature beginning at approximately hour
2:00.
[0203] FIG. 7 Lowest core body temperature. The lowest core body
temperature recorded for a mouse exposed to 80 ppm hydrogen sulfide
was 10.7.degree. C. Triangles indicate the core body temperature of
the mouse as determined by radiotelemetry which started at
approximately 39.degree. C. at time 0. Diamonds indicate the
ambient temperature which began at approximately 23.degree. C. and
was dropped to less than 10.degree. C. by the mid-point of the
experiment, after which it was then increased again toward room
temperature.
[0204] FIG. 8A Endogenous levels of hydrogen sulfide are increased
in mice acclimated to warm temperatures. Gray bars (two left bars)
indicate endogenous H.sub.2S concentrations of two individual mice
acclimated to 4.degree. C.; black bars (two right bars) indicate
the endogenous H.sub.2S concentrations of two individual mice
acclimated to 30.degree. C. Hydrogen sulfide concentration
determined by GC/MS.
[0205] FIG. 8B Effects of Ambient Temperature on Hydrogen Sulfide
Dependent Temperature prop. The rate of core temperature (expressed
in degrees Centigrade) drop due to hydrogen sulfide exposure is
dependent on the acclimation temperature. The mice were exposed to
the gas at 1:00. Triangles indicate the core body temperature of
the mouse, acclimated to 12.degree. C., as determined by
radiotelemetry. Squares indicate the core body temperature of the
animal acclimated to 30.degree. C.
[0206] FIG. 9 is a block diagram illustrating a respiration gas
delivery system according to embodiments of the present
invention.
[0207] FIG. 10 is a schematic drawing illustrating a respiration
gas delivery system according to embodiments of the present
invention.
[0208] FIG. 11 is a schematic drawing illustrating a respiration
gas delivery system according to further embodiments of the present
invention.
[0209] FIG. 12 is a flowchart illustrating operations according to
embodiments of the present invention.
[0210] FIG. 13 is a schematic drawing illustrating a tissue
treatment gas delivery system according to embodiments of the
present invention.
[0211] FIG. 14 is a flowchart illustrating operations according to
embodiments of the present invention.
[0212] FIG. 15 Metabolic inhibition protects against
hypothermia-induced death in Nematodes. Nematodes exposed to cold
temperatures (4.degree. C.) are unable to survive after 24 hours.
However, if kept in anoxic conditions during the period of
hypothermia (and for a 1 hour period before and after), a
substantial proportion of the nematodes survive.
[0213] FIG. 16 Short CO.sub.2 pretreatment leads to greatest
extension of anoxic survival. Adult flies were exposed to 100%
CO.sub.2 for the indicated time, the atmosphere was made anoxic by
flushing with N.sub.2, and then the tube was sealed. After 22 h,
the tubes were opened to room air. The flies were allowed to
recover for 24 h before scoring viability.
[0214] FIG. 17 CO.sub.2 variably enhances anoxic survival. Adult
flies were made anoxic in low-flow experiment, either directly from
room air (no pretreatment) or after being exposed to 100% CO.sub.2
for 10 min. After the indicated time, the tubes were opened to room
air. The flies were allowed to recover for 24 h before scoring
viability.
[0215] FIG. 18 50 ppm H.sub.2S added to CO increases fraction of
flies that survive anoxia. Adult flies were made anoxic in low-flow
experiments, either directly from room air (no pretreatment) or
after being exposed to 50 ppm H.sub.2S balanced with CO.
[0216] FIG. 19 is a schematic diagram of an example system for
removing oxygen from platelets and a solution in accordance with
embodiments of the present disclosure.
[0217] FIG. 20A-B show the change in core temperature of rats
exposed to hydrogen sulfide (A) and mice exposed to carbon dioxide
(B).
[0218] FIG. 21 Gas Matrix showing stepwise experimental plan to
determine concentration of active compounds.
[0219] FIG. 22A-B show negative pressure devices that can be used
to deliver or administer active compounds.
[0220] FIG. 23 Survival of Mice in 5% Oxygen. Mice were exposed to
either 30 minutes of room air before exposure to 5% O.sub.2
(control; black line; n=9) or 10 minutes of room air followed by 20
minutes of 150 ppm H.sub.2S before exposure to 5% O.sub.2
(experimental; red line; n=20) and their length of survival
measured. Experiments were stopped at 60 minutes and if the animals
were still alive (all of the experimental, none of the controls)
they were returned to their cage.
[0221] FIG. 24 H.sub.2S Increases Survival at Lethal Oxygen
Tensions. Chart showing results of experiment described in FIG. 23.
The x-axis shows the time in minutes that the mice survived in the
lower oxygen tensions. The dark bars show when H.sub.2S is absent
while the lighter bars show when H.sub.2S is present. In the latter
groups, mice were exposed to 150 ppm H.sub.2S prior to the oxygen
tension being reduced to between 5% and 2.5%. Survival times were
measured and was at least 60 minutes in all the H.sub.2S treated
groups.
[0222] FIG. 25 Metabolic Rate of a Mouse in 5% Oxygen. A mouse was
exposed to 10 minutes of room air followed by 20 minutes of 150 ppm
H.sub.2S prior to exposure to 5% O.sub.2. Metabolic rate measured
by CO.sub.2 output. Pre-exposure CO.sub.2 output was approximately
2500 ppm, after 20 minutes of H.sub.2S then metabolic rate was down
approximately 2-fold and after several hours of exposure to 5%
O.sub.2 the CO.sub.2 output had dropped approximately 50-fold from
pre-exposure levels to approximately 50 ppm. At hour 6 the mouse
was returned to room air and allowed to recover. This data is from
one of the mice included in FIG. 23 (experimental group).
[0223] FIG. 26 Mouse Exposed to 100 ppb H.sub.2Se. Chart shows
exposure to H.sub.2Se in minutes (x-axis) with drop in core body
temperature (temperature in celsius shown on right plotted with
line showing gradual decrease) and with decrease in respiration
(ppm CO.sub.2 shown on left plotted with jagged line showing
decrease).
[0224] FIG. 27 Mouse Exposed to 10 ppb H.sub.2Se. Chart shows
exposure to H.sub.2Se in minutes (x-axis) with drop in core body
temperature (temperature in celsius shown on right plotted with
line showing gradual decrease) and with decrease in respiration
(ppm CO.sub.2 shown on left plotted with jagged line showing
decrease with lowest point at five minute exposure).
[0225] FIG. 28 H.sub.2S Pre-treatment Enhances Survival of Mice
Under Hypoxic Conditions. Mice were exposed to either 30 minutes of
room air (No PT) or 10 minutes of room air followed by 20 minutes
of 150 ppm H.sub.2S (PT) before exposure to 5% O.sub.2 (5%), 4%
O.sub.2 (4%), 5% O.sub.2 for 1 hr followed by 4% O.sub.2 (4%+1 hr
5%), or 5% O.sub.2 for 1 hr followed by 3% O.sub.2 (3%+1 hr 5%),
and their length of survival measured. Experiments were stopped at
60 minutes and if the animals still alive were returned to their
cage.
[0226] FIG. 29 CO.sub.2 Production During Transition to Lethal
Hypoxia. Changes in CO.sub.2 production upon transition to either
5% O.sub.2 or 4% O.sub.2 were measured in mice exposed to either
room air for 30 minutes (No PT) or room air for 10 minutes followed
by 150 ppm H.sub.2S for 20 minutes (PT). In addition, the change in
CO.sub.2 production upon step-wise transition to 5% O.sub.2 for 1
hr followed by 4% O.sub.2 was measured. The percent change in
CO.sub.2 production is plotted with standard error indicated.
[0227] FIG. 30 Human keratinocytes survive exposure to 100% carbon
monoxide (CO). Cells were inspected visually using an inverted
phase contrast microscope. Quantitation of the number of viable
keratinocytes as judged by trypan blue staining, which is an
indicator of cell death.
[0228] FIG. 31 Chronic exposure to low levels of H.sub.2S leads to
heat resistance in C. elegans. Nematodes adapted to environments
containing approximately 50 ppm H.sub.2S in house air, were
significantly more resistant to lethal effects of elevating the
ambient temperature to 35 degrees C. compared to siblings raised in
house air alone.
[0229] FIG. 32 Chronic exposure to low levels of H.sub.2S increases
lifespan in C. elegans. Nematodes that were adapted to environments
containing approximately 50 ppm H.sub.2S in house air had longer
lifespan compared to untreated controls.
[0230] FIG. 33 Examples of transient core temperature drop in
Sprague-Dawley rats. Core temperature measurements from rats
exposed to 0.03% hydrogen sulfide mixed with room air (gray/dotted
line) or 15% carbon dioxide/8% oxygen/77% helium (dark/solid line).
In this experiment the temperature of the environmental chamber was
10.degree. C. during the treatment phase. The temperature of the
environmental chamber was restored to room temperature (22.degree.
C.) when the gas was returned to room air. In each case this was
the point (approximately 2 hours for the dark/solid line and
approximately 7.4 hours for the gray/dotted line) where the core
temperature began to rise.
[0231] FIG. 34 Mouse core body temperature during exposure to 1.2
ppm of hydrogen selenide for 2 hours and 10 minutes in room air at
5.degree. C. ambient temperature.
[0232] FIG. 35 Rat core body temperature during exposure to room
air in an environmental chamber at an ambient temperature of
10.degree. C. Dark line describes the core temperature of the rat.
The gray line describes the ambient temperature.
[0233] FIG. 36 Core body temperature of a rat exposed to 80% helium
20% oxygen at an ambient temperature of 7.degree. C. Time is
described on the X axis in hours. The total time of exposure was
approximately 5 hours (from 9:15 AM to 2:15 PM). No significant
drop in core body temperature was seen.
[0234] FIG. 37 Core body temperature of a rat during exposure to
15% carbon dioxide, 20% oxygen, and 75% Helium at an ambient
temperature of 7.degree. C. The time of exposure was approximately
2 hours. The rat was exposed to room air beginning at the point
where the temperature begins to rise (shortly after the point
labeled 38512.6). During the period when the rat was exposed to
room air the temperature of the environment was restored to room
temperature.
[0235] FIG. 38. Core temperature of a rat exposed to 15% carbon
dioxide, 8% oxygen, and 77% Helium at an ambient temperature of
7.degree. C. The exposure time was approximately 4 hours. The gray
line describes the ambient temperature. The dark line describes the
core temperature. At the point where the ambient and cores
temperatures rise is the point where the gas was switched to room
air.
[0236] FIG. 39. Core temperature of a dog exposed to carbon
dioxide/helium/oxygen. Dotted lines are when the gas went on
(approximately 24 minutes) and off (approximately 55 minutes). FIG.
40. Core temperature of a dog exposured to increasing
concentrations of carbon dioxide. Dotted lines indicate when
changes in the gas were made. At approximately 63 minutes the gas
was changed from room air to 9% carbon dioxide in room air. At
approximately 85 minutes the atmosphere was changed from 9% carbon
dioxide in room air to 12% carbon dioxide in room air. At
approximately 115 minutes the atmosphere was changed from 12%
carbon dioxide in room air to 15% carbon dioxide in room air. The
experiment ended at approximately 135 minutes.
[0237] FIG. 41 Apparatus employed in screening methods.
[0238] FIG. 42 Oxygen consumption (gray bars) and carbon dioxide
production (black bars) of animals exposed to hydrogen sulfide for
4 hours per day for at least 1 week and for control animals that
were exposed to the same conditions lacking hydrogen sulfide.
[0239] FIG. 43 Respiratory quotient for animals exposed to hydrogen
sulfide for 4 hours per day for at least 1 week (H.sub.2S 2900 and
H.sub.2S 2865) and for control animals (2893 and 2894) that were
exposed to the same conditions lacking hydrogen sulfide.
DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
I. Stasis
[0240] In "stasis" or "suspended animation," a cell, tissue or
organ, or organism (collectively referred to as "biological
material") is living, but cellular functions necessary for cell
division, developmental progression, and/or metabolic state are
slowed or even stopped. This state is desirable in a number of
contexts. Stasis can be used as a method of preservation by itself,
or it may be induced as part of a cryopreservation regimen.
Biological materials may be preserved for research use, for
transportation, for transplantation, for therapeutic treatment
(such as ex vivo therapy), and to prevent the onset of trauma, for
example. Stasis with respect to entire organisms has similar uses.
For instance, transportation of organisms could be facilitated if
they had entered stasis. This might reduce physical and
physiological damage to the organism by reducing or eliminating
stress or physical injury. These embodiments are discussed in
further detail below. Stasis may be beneficial by decreasing the
need of the biological material for oxygen and, therefore,
bloodflow. It may extend the period of time that biological
material can be isolated from a life-sustaining environment and
exposed to a death-inducing environment.
[0241] While recovery has been reported from accidental hypothermia
for a relatively prolonged period of time (Gilbert et al., 2000),
there has been recent interest in intentionally inducing suspended
animation in organisms. (The discussion of any reference is not to
be construed as an admission that the reference constitutes prior
art. In fact, some references discussed herein would not be prior
art with respect to the priority applications.) Controlled
hyperthermia has been explored, as well as the administration of a
cold flush of a solution into the aorta (Tisherman, 2004),
induction of cardiac arrest (Behringer et al., 2003), or nitric
oxide-induced suspended animation (Teodoro et al., 2004).
[0242] An organism in stasis is distinguishable from an organism
under general anesthesia. For example, an organism in mild stasis
(between about 2- and about 5-fold decrease in cellular
respiration) that is exposed to room air will begin to shiver,
while an organism under anesthesia will not. Also, an organism in
mild stasis is anticipated to respond to a toe squeeze, while an
organism under anesthesia usually does not. Consequently, stasis is
not the same thing as being under anesthesia as it is commonly
practiced.
[0243] CO.sub.2 production is a direct marker of cellular
respiration related to metabolism of an organism. This may be
distinguished from "CO.sub.2 evolution," which refers to the amount
of CO.sub.2 blown out of the lungs. Certain active compounds, e.g.,
hydrogen sulfide, can inhibit carbonic anhydrase activity in the
lungs, this inhibiting conversion of carbonate to CO.sub.2 and its
liberation from the pulmonary blood, thereby exhibiting an
associated reduction in CO.sub.2 evolution, without a corresponding
decrease in cellular CO.sub.2 production.
[0244] The present invention is based on the observation that
certain types of compounds effectively induce reversible stasis in
biological matter. Other patent applications discuss induction of
stasis, including the following: U.S. patent application Ser. Nos.
10/971,576, 10/972,063, and 10/971,575; U.S. patent application
Ser. No. 10/971,576; U.S. patent application Ser. No. 10/972,063;
and U.S. patent application Ser. No. 10/971,575, all of which are
hereby incorporated by reference.
[0245] A. Thermoregulation
[0246] Stasis in a warm-blooded animal will affect
thermoregulation. Thermoregulation is a characteristic of so-called
"warm-blooded" animals, which permits the organism to maintain a
relatively constant core body temperature even when exposed to
significantly altered (cold or hot) environmental temperatures. The
ability to control thermoregulation by induction of stasis is one
aspect of the invention, and permits uses similar to those
discussed above.
[0247] Thermal regulation may be facilitated by placing of
organisms, limbs or isolated organs or tissues into
chambers/devices, the temperature of which can be controlled. For
example, warm rooms or chamber-like devices similar to hyperbaric
chambers may encompass an entire organism and be connected to
thermo-regulatory apparti. Smaller devices such as blankets,
sleeves, cuffs or gloves (e.g., CORE CONTROL cooling system by
AVAcore Technologies, Palo Alto, Calif., U.S. Pat. No. 6,602,277)
are also contemplated. Such chambers/devices may be used both to
increase or reduce ambient temperatures.
[0248] B. Biological Matter
[0249] Biological matter contemplated for use with the present
invention include material derived from invertebrates and
vertebrates, including mammals; biological materials includes
organisms. In addition to humans, the invention can be employed
with respect to mammals of veterinary or agricultural importance
including those from the following classes: canine, feline, equine,
bovine, ovine, murine, porcine, caprine, rodent, lagomorph, lupine,
and ursine. The invention also extends to fish and birds. Other
examples are disclosed below.
[0250] Moreover, the type of biological matter varies. It can be
cells, tissues and organs, as well as organisms for which different
compositions, methods, and apparatuses have relevance. The
nonprovisional U.S. patent application Ser. Nos. 10/971,576,
10/972,063, and 10/971,575 are hereby incorporated by reference in
their entireties.
[0251] In some embodiments, the biological material is or comprises
cells. It is contemplated that the cell may be any oxygen-utilizing
cell. The cell may be eukaryotic or prokaryotic. In certain
embodiments, the cell is eukaryotic. More particularly, in some
embodiments, the cell is a mammalian cell. Mammalian cells
contemplated for use with the invention include, but are not
limited to those that are from a: human, monkey, mouse, rat,
rabbit, hamster, goat, pig, dog, cat, ferret, cow, sheep, and
horse.
[0252] Moreover, cells of the invention may be diploid, but in some
cases, the cells are haploid (sex cells). Additionally, cells may
be polyploid, aneuploid, or anucleate. The cell can be from a
particular tissue or organ, such as one from the group consisting
of: heart, lung, kidney, liver, bone marrow, pancreas, skin, bone,
vein, artery, cornea, blood, small intestine, large intestine,
brain, spinal cord, smooth muscle, skeletal muscle, ovary, testis,
uterus, and umbilical cord. Moreover, the cell can also be
characterized as one of the following cell types: platelet,
myelocyte, erythrocyte, lymphocyte, adipocyte, fibroblast,
epithelial cell, endothelial cell, smooth muscle cell, skeletal
muscle cell, endocrine cell, glial cell, neuron, secretory cell,
barrier function cell, contractile cell, absorptive cell, mucosal
cell, limbus cell (from cornea), stem cell (totipotent, pluripotent
or multipotent), unfertilized or fertilized oocyte, or sperm.
[0253] 1. Different Sources
[0254] The following are examples of sources from which biological
matter may be obtained. Embodiments of the invention include, but
are not limited to, these examples.
[0255] a. Mammals
[0256] In certain aspects of the invention, the mammal is of the
Order Monotremata, Marsupialia, Insectivora, Macroscelidia,
Dermoptera, Chiroptera, Scandentia, Primates, Xenarthra, Pholidota,
Tubulidentata, Lagomorpha, Rodentia, Cetacea, Carnivora,
Proboscidea, Hyracoidea, Sirenia, Perissodactyla, or
Artiodactyla.
[0257] Examples of Monotremata include the Families Tachyglossidae
(e.g., Echidnas) and Ornithorhynchidae (e.g., Platypus). Examples
of Marsupialia include the Families Didelphidae (e.g., Opossums),
Microbiotheriidae (e.g., Monito del Monte), Caenolestidae (e.g.,
Rat Oppossums), Dasyuridae (e.g., Marsupial mice), Myrmecobiidae
(e.g., Numbat), Thylacinidae (e.g., Thylacine), Peramelidae (e.g.,
Bandicoots), Thylacomyidae (e.g., Rabbit Bandicoots), Notoryctidae
(e.g., Marsupial Moles), Phalangeridae (e.g., Cuscuses), Petauridae
(e.g., Ringtails, Gliders), Burramyidae (e.g., Pygmy Possums),
Macropodidae (e.g., Kangaroos, Wallabies), Tarsipedidae (e.g.,
Honey Possum), Vombatidae (e.g., Wombats), and Phascolarctidae
(e.g., Koalas).
[0258] Insectivora includes, for example, the Families
Solenodontidae (e.g., Solenodons), Tenrecidae (e.g., Tenrecs, Otter
Shrews), Chrysochloridae (e.g., Golden Moles), Erinaceidae (e.g.,
Hedgehogs, Moonrats), Soricidae (e.g., Shrews), and Talpidae (e.g.,
Moles, Desmans). The Order Macroscelidia includes the Family
Macroscelidia (e.g., Elephant Shrews). The Order Scandentia
includes Tupaiidae (e.g., Tree Shrews). The Order Dermoptera
includes the Family Cynocephalidea (e.g., Flying Lemurs).
Chiroptera includes the Families Pteropodidae (e.g., Fruit Bats,
Flying Foxes), Rhinopomatidae (e.g., Mouse-Tailed Bats),
Craseonycteridae (e.g., Hog-Nosed or Bumblebee Bat), Emballonuridae
(e.g., Sheath-Tailed Bats), Nycteridae (e.g., Slit-Faced Bats),
Megadermatidae (e.g., False Vampire Bats), Rhinolophidae (e.g.,
Horshoe Bats), Noctilionidae (e.g., Bulldog Bats, Fisherman Bats),
Mormoopidae, Phyllostomidae (e.g., New World Leaf-Nosed Bats),
Natalidae, Furipteridae, Thyropteridae, Myzapodidae,
Vespertilionidae (e.g., Common Bats), Mystacinidae (e.g.,
Short-Tailed Bats), and Molossjdae (e.g., Free-Tailed Bats).
[0259] The Order Primates includes the Families Lemuridae (e.g.,
Lemurs), Chemogaleidae (e.g., Mouse Lemurs), Indriidae (e.g.,
Indri, Woolly Lemur), Daubentoniidae (e.g., Aye-Aye), Lorisidae
(e.g., Lorises, Bushbabies, Galagos), Tarsiidae (e.g., Tarsiers),
Cebidae (e.g., New World Monkeys, Marmosets, Tamarins), Hylobatidae
(e.g., Gibbons), Pongidae (e.g., Apes), and Hominidae (e.g.,
Man).
[0260] Examples of Xenarthra include Myrmecophagidae (e.g.,
Anteaters), Bradypodidae (e.g., Three-Toed Sloths), Megalonychidae
(e.g., Two-Toed Sloths), and Dasypodidae (e.g., Armadillos).
Examples of Pholidota include Manidae (e.g., Pangolins). Examples
of Tubulidentata include Orycteropodidae (e.g., Aardvarks).
Examples of Lagomorpha include Ochotonidae (e.g., Pikas) and
Leporidae (e.g., Hares and Rabbits).
[0261] The Order Rodentia includes the Families Aplodontidae (e.g.,
Mountain Beavers), Sciuridae (e.g., Squirrels, Marmots, Chipmunks),
Geomyidae (e.g., Pocket Gophers), Heteromyidae (e.g., Pocket Mice,
Kangaroo Rats), Castoridae (e.g., Beaver), Anomaluridae (e.g.,
Scaly-Tailed Squirrels), Pedetidae (e.g., Springhare), Muridae
(e.g., Rats and Mice), Gliridae (e.g., Dormice), Seleviniidae
(e.g., Desert Dormouse), Zapodidae (e.g., Jumping Mice), Dipodidae
(e.g., Jerboas), Hystricidae (e.g., Old World Porcupines),
Erethizontidae (e.g., New World Porcupines), Caviidae (e.g., Guinea
Pigs, Maras), Hydrochaeridae (e.g., Capybara), Dinomyidae (e.g.,
Pacarana), Agoutidae (e.g., Pacas), Dasyproctidae (e.g., Agoutis),
Chinchillidae (e.g., Chinchillas, Viscachas), Capromyidae (e.g.,
Hutias), Myocastoridae (e.g., Nutria), Ctenomyidae (e.g.,
Tuco-Tucos), Octodontidae (e.g., Octodonts, Degus), Abrocomidae
(e.g., Chichilla Rats), Echimyidae (e.g., Spiny Rats),
Thryonomyidae (e.g., Cane Rats), Petromyidae (e.g., African Rock
Rat), Bathyergidae (e.g., Mole Rat), and Ctenodactylidae (e.g.,
Gundis).
[0262] The Order Cetacea includes the Families Imidae (e.g., Amazon
Popoise), Lipotidae, Platanistidae, Pontoporiidae, Ziphiidae (e.g.,
Beaked Whales), Physeteridae (e.g., Sperm Whales), Monodontidae
(e.g., Beluga Whale, Narwhal), Delphinidae (e.g., Marine Dolphins,
Killer Whales), Phocoenidae (e.g., Porpoises), Balaenopteridae
(e.g., Rorquals), Balaenidae (e.g., Right Whales), and
Eschrichtiidae (e.g., Gray Whales).
[0263] The Order Camivora includes the Families Canidae (e.g.,
Dogs, Foxes, Wolves, Jackals, Coyotes), Ursidae (e.g., Bears),
Procyonidae (e.g., Raccoons, Coatis, Kinkajous, Lesser Pandas),
Ailuropodidae (e.g., Giant Pandas), Mustelidae (e.g., Weasels,
Skunks, Badgers, Otters), Viverridae (e.g., Civets, Genets),
Herpestidae (e.g., Mongooses), Protelidae (e.g., Aardwolf),
Hyaenidae (e.g., Hyenas), Felidae (e.g., Cats), Otariidae (e.g.,
Eared Seals, Sea Lions), Odobenidae (e.g., Walrus), and Phocidae
(e.g., Earless Seals).
[0264] The Order Proboscidea includes the Family Elephantidae
(e.g., Elephants). Hyracoidea includes the Family Procaviidae
(e.g., Hyraxes). Sirenia includes the Families Dugongidae (e.g.,
Dugong) and Trichechidae (e.g., Manatees). The Order Perissodactyla
includes the Families Equidae (e.g., Horses, Assess, Zebras),
Tapiridae (e.g., Tapirs), and Rhinocerotidae (e.g., Rhinoceroses).
The Order Artiodactyla includes the Families Suidae (e.g., Pigs,
Babirusa), Tayassuidae (e.g., Peccaries), Hippopotamidae (e.g.,
Hippopotamuses), Camelidae (e.g., Camels, Llamas, Vicunas),
Tragulidae (e.g., Chevrotains), Moschidae (e.g., Musk Deer),
Cervidae (e.g., Deer, Elk, Moose), Giraffidae (e.g., Giraffe,
Okapi), Antilocapridae (e.g., Pronghom), and Bovidae (e.g., Cattle,
Sheep, Antelope, Goats).
[0265] b. Reptiles
[0266] In certain embodiments, the biological material is a reptile
or is derived from a reptile. The reptile may be of the Order
Chelonia, Pleurodira, Squamata, Rhynchocephalia, or Crocodylia. A
reptile of the Order Chelonia may be, for example, a
Carettochelyidae, Chelydridae (e.g., Snapping Turtles), Cheloniidae
(e.g., Loggerhead Turtles, Green Turtles), Dermatemydidae (e.g.,
Leatherback Turtles), Emydidae (e.g., Paitned Turtles, Pond
Sliders, Pond Turtles, Snail-Eating Turtles, Box Turtles),
Kinosternidae (e.g., Stinkpot Turtles), Saurotypidae, Testudinidae
(e.g., Galapagos Tortoises, Desert Tortoises, Aldabra Turtles,
Spu-Thighed Tortoises, Hermann's Tortoise), Trionychidae (e.g.,
Chinese Softshells, Spiny Softshells), or a Platysternidae. A
reptile of the Order Pleurodira may be, for example, a Chelidae
(e.g., Snake-Necked Turtles) or Pelomedusidae (e.g., Helmeted
Turtles).
[0267] A reptile of the Order Squamata may be, for example, an
Agamidae (e.g., Rainbow Lizards, Bearded Dragons, Indian
Bloodsuckers, Spiny-Tailed Lizards), Chamaeleontdidae (e.g.,
Chameleons), Iguanidae (e.g., Anoles, Basilisks, Collared Lizards,
Iguanas, Horned Lizards, Chuckwallas, Sagebrush Lizards,
Side-Blotched Lizards), Gekkonidae (e.g., Geckos), Pygopodidae,
Teiidae (e.g., Race Runners, Tegus), Lacertidae (e.g., Sand
Lizards, Ocellated Lizards, Viviparous Lizards, Wall Lizards,
Long-Tailed Lizards), Xantuslidae, Scincidae (e.g., Skinks),
Cordylidae (e.g., Sungazers), Dibamidae, Xenosauridae, Anguidae
(e.g., Slow Worm, Alligator Lizards, Sheltopusik, Glass Lizards),
Helodermatidae (e.g., Gila Monster), Lanthanotidae, Varanidae
(e.g., Monitors), Leptotyphlopidae, Typhlopidae, Anomalepididae,
Aniliidae (e.g., Pipe Snakes), Uropeitidae, Xenopeltidae, Boidae
(e.g., Boas, Anacondas, Rock Pythons), Acrochordidae (e.g., Wart
Snakes), Colubridae (e.g., Mangrove Snakes, Whip Snakes, Smooth
Snakes, Egg-Eating Snakes, Boomslangs, Rat Snakes, Aesculapian
Snakes, Four-Lined Snakes, Oriental Beauty Snake, Tentacled Snakes,
Hognose Snakes, Kingsnakes, Montpelier Snakes, Grass Snakes, Water
Snakes, Garter Snakes, Twig Snakes, Keelback Snakes), Elapidae
(e.g., Death Adders, Kraits, Mambas, Coral Snakes, Cobras,
Copperhead, Puff Adder), Viperidae (e.g., Vipers, Right Adders,
Rattlesnakes, Massasaugas, Adder), Hydrophiidae (e.g., Sea Brait),
Amphisbaenidae (e.g., Worm Lizard), Bipedidae, or a Trogonophidae
(e.g., Burrowing Lizard).
[0268] A reptile of the Order Rhynchocephalia may be, for example,
a Sphenodontidae (e.g., Tuataras). A reptile of the Order
Crocodylia may be, for example, an Alligatoridae (e.g., Alligators,
Caiman), Crocodylidae (e.g., Crocodiles), or a Gavialidae (e.g.,
Gharials).
[0269] c. Amphibians
[0270] The biological material of the present invention may be an
amphibian or may be derived from an amphibian. The amphibian may
be, for example, a frog or a toad. The frog or toad may be, for
example, an Arthroleptidae (e.g., screeching frogs), Ascaphidae
(e.g., tailed frogs), Brachycephalidae (e.g., gold frogs and shield
toads), Bufonidae (e.g., true toads), Centrolenidae (e.g., glass
frogs and leaf frogs), Dendrobatidae (e.g., poison-dart frogs),
Discoglossidae (e.g., fire-bellied toads), Heleophrynidae (e.g.,
ghost frogs), Hemisotidae (e.g., shovel-nosed frogs), Hylidae
(e.g., New World tree frogs), Hyperoliidae (e.g., African tree
frogs), Leiopelmatidae (e.g., New Zealand frogs), Leptodactylidae
(e.g., neotropical frogs), Megophryidae (e.g., South Asian frogs),
Microhylidae (e.g., microhylid frogs), Myobatrachidae (e.g.,
Australian frogs), Pelobatidae (e.g., spadefoot toads), Pelodytidae
(e.g., parsley frogs), Pipidae (e.g., tongueless frogs), Pseudidae
(e.g., paradox frogs), Ranidae (e.g., riparian frogs and true
frogs), Rhacophoridae (e.g., Old World tree frogs), Rhinodermatidae
(e.g., Darwin's frogs), Rhinophrynidae (e.g., burrowing toad),
Sooglossidae (e.g., Seychelle frogs), Caudata (e.g., salamanders),
or a Gymnophiona (e.g., caecilians).
[0271] The amphibian may be a salamander. The salamander may be,
for example, an Ambystomatidae (e.g., mole salamanders),
Amphiumidae (e.g., amphiumas), Cryptobranchidae (e.g., giant
salamanders and hellbenders), Dicamptodontidae (e.g., Pacific giant
salamanders), Hynobiidae (e.g., Asiatic salamanders),
Plethodontidae (e.g., lungless salamanders), Proteidae (e.g.,
mudpuppies and waterdogs), Rhyacotritonidae (e.g., torrent
salamanders), Salamandridae (e.g., newts and salamanders), or a
Sirenidae (e.g., sirens). Alternatively, the amphibian may be a
Caecilian. The Caecilian may be, for example, a Caeciliidae (e.g.,
caecilians), Ichthyophiidae (e.g., Asiatic tailed caecilians),
Rhinatrematidae (e.g., neotropical tailed caecilians),
Scolecomorphidae (e.g., African caecilians), Typhlonectidae (e.g.,
aquatic caecilians), or an Uraeotyphlidae (e.g., Indian
caecilians).
[0272] d. Birds
[0273] The biological material of the present invention may be a
bird or may be derived from a bird. The bird may be, for example,
an Anseriforme (e.g., waterfowl), Apodiforme (e.g., hummingbirds
and swifts), Caprimulgiforme (e.g., nightbirds), Charadriiforme
(e.g., shorebirds), Ciconiiforme (e.g., storks), Coliiforme (e.g.,
mousebirds), Columbiforme (e.g., doves and pigeons), Coraciiforme
(e.g., kingfishers), Craciforme (e.g., chacalacas, curassows,
guans, megapodes), Cuculiforme (e.g., cuckoos, hoatzin, turacos),
Falconiforme (e.g., diurnal birds of prey), Galliforme (e.g.,
chicken-like birds), Gaviiforme (e.g., loons), Gruiforme (e.g.,
coots, cranes, rails), Passeriforme (e.g., perching birds),
Pelecaniforme (e.g., pelicans), Phoenicopteriforme (e.g.,
flamingos), Piciforme (e.g., woodpeckers), Podicipediforme (e.g.,
grebes), Procellariiforme (e.g., tube-nosed seabirds),
Psittaciforme (e.g., parrots), Sphenisciforme (e.g., penguins),
Strigiforme (e.g., owls), Struthioniforme (e.g., cassowaires, emus,
kiwis, ostriches, rheas), Tinamiforme (e.g., tinamous),
Trogoniforme (e.g., trogons), or a Turniciforme (e.g.,
buttonquail).
[0274] e. Fish
[0275] The biological material of the present invention may be a
fish or may be derived from a fish. The fish may be, for example,
an Acipenseriforme (e.g., paddlefishes, spoonfishes, and
sturgeons), Polypteriforme (e.g., bichirs, birchers, lobed-finned
pike, and reed fishes), Atheriniforme (e.g., rainbow fishes and
silversides), Beloniforme (e.g., halfbeeks and needlefishes),
Beryciforme, Channiforme, Cyprinodontiforme (e.g., killifishes),
Dactylopteriforme (e.g., flying gurnards), Gasterosteiforme (e.g.,
pipefishes and sticklebacks), Mugiliforme (e.g., mullets),
Pegasiforme (e.g., dragonfishes and sea moths), Perciforme (e.g.,
perch-like fishes), Pleuronectiforme (e.g., flatfishes, flounders,
and soles), Scorpaeniforme (e.g., scorpion fishes and sculpins),
Stephanoberyciforme, Synbranchiforme (e.g., swamp eels),
Tetraodontiforme (e.g., cowfishes, filefishes, leatherjackets,
puffers, triggerfishes, and trunkfishes), Zeiforme (e.g.,
boarfishes, dories, and john dories), Atherinomorpha, Clupeiforme
(e.g., anchovies and herrings), Aulopiforme, Albuliforme,
Anguilliforme (e.g., eels), Elopiforme (e.g., tarpons),
Notacanthiformes (e.g., spiny eels and tapirfishes),
Saccopharyngiformes, Lampridiforme (e.g., opahs and ribbonfishes),
Characiforme (e.g., leporins and piranhas), Cypriniforme (e.g.,
minnows, suckers, zebra fish), Gonorhynchiforme (e.g., milkfish and
shellears), Gymnotiforme, Siluriforme (e.g., catfishes),
Aphredoderiforme (e.g., cavefishes and pirate perches),
Batrachoidiforme, Gadiforme (e.g., cods and hakes), Gobiesociforme,
Lophiiforme (e.g., anglerfishes), Ophidiiforme, Percopsiforme
(e.g., trout-perches), Polymixiiforme (e.g., beardfishes),
Cetomimiforme, Ctenotlirissiforme, Esociforme (e.g., mudminnows and
pikes), Osmeriforme (e.g., Argentines and smelts), Salmoniforme
(e.g., salmons), Myctophiforme (e.g., Latern Fishes),
Ateleopodiforme, Stomiiforme, Amiiforme (e.g., bowfins),
Semionotiforme (e.g., gars), Syngnathiforme (e.g., pipefishes and
seahorses), Ceratodontiforme (e.g., Australian lungfishes),
Lepidosireniforme (e.g., South American lungfishes and African
lungfishes), or a Coelacanthiforme (e.g., coelacanths).
[0276] f. Invertebrates
[0277] The biological material maybe an invertebrate or derived
from an invertebrate. The invertebrate may be, for example, a
Porifera (e.g., sponges), Cnidaria (e.g., jellyfish, hydras, sea
anemones, Portuguese man-of-wars, and corals), Platyhelminthe
(e.g., flatworms, including planaria, flukes, and tapeworms),
Nematoda (e.g., roundworms, including rotifers and nematodes),
Mollusca (e.g., mollusks, snails, slugs, octopuses, squids),
Annelida (e.g., segmented worms, including earthworms, leeches, and
marine worms), Echinodermata (e.g., sea stars, sea cucumbers, sand
dollars, sea urchins), Phoronida (e.g., Horseshoe Worms),
Tardigrada (e.g., Water Bears), Acanthocephala (e.g., Spiny Headed
Worms), Ctenophora (e.g., Comb Jellies), or an Arthropod (e.g.,
arachnids, crustaceans, millipedes, centipedes, insects).
[0278] An Arthropod may be, for example, a Coleoptera (e.g.,
beetles), Diptera (e.g., true flies), Hymenoptera (e.g., ants,
bees, wasps), Lepidoptera (e.g., butterflies, moths), Mecoptera
(e.g., scorpion flies), Megaloptera, Neuroptera (e.g., lacewings
and relatives), Siphonaptera (e.g., fleas), Strepsiptera (e.g.,
parasitic insects and twisted-winged parasites), Trichoptera (e.g.,
caddisflies), Anoplura (e.g., sucking lice), Hemiptera (e.g., true
bugs and their relatives), Mallophaga (e.g., biting lice),
Psocoptera (e.g., psocids), Thysanoptera (e.g., thrips), Orthoptera
(e.g., grasshoppers, locusts), Dermaptera (e.g., earwigs),
Dictyoptera, Embioptera (e.g., webspinners), Grylloblattodea,
Mantophasmatodea (e.g., gladiators), Plecoptera (e.g., stoneflies),
Zoraptera (e.g., zorapterans), Ephemeroptera (e.g., mayflies),
Odonata (e.g., dragonflies and damselflies), Phasmatoptera (e.g.,
walkingsticks), Thysanura (e.g., bristletails), Archaeognatha,
Collembola (e.g., snow flies and springtails), Chilopoda (e.g.,
centipedes), Diplopoda (e.g., millipedes), Pauropoda (e.g.,
pauropods, pauropodans, and progoneates), Symphyla (e.g.,
pseudocentipedes and symphylans), Malacostraca (e.g., crabs, krill,
pill bugs, shrimp), Maxillopoda, Branchiopoda (e.g., branchiopods),
Cephalocarida, Ostracoda (e.g., ostracods), Remipedia, Branchiura,
Cirripedia (e.g., barnacles), Arachnida (e.g., arachnids, including
amblypygids, spiders, daddy longlegs, harvestmen, microscorpions,
book scorpions, false scorpions, pseudoscorpions, scorpions,
solpugids, sun spiders, and uropygids), Merostomata (e.g.,
horseshoe crabs), or a Pycnogonida (e.g., sea spiders).
[0279] g. Fungi
[0280] The biological material of the present invention may be a
fungi or may be derived from a fungi. The fungi may be, for
example, an Ascomycota (sac fungi), Basidiomycota (club fungi),
Chytridiomycota (chytrids), Deuteromycota, or a Zygomycota. The
fungi may be a Rhizopus, Pilobolus, Arthrobotrys, Aspergillus,
Allomyces, Chytridium, Agaricus, Amanita, Cortinarius, Neurospora,
Morchella, Saccharomyces, Pichia, Candida, Schizosaccharomyces, or
Ergot. In particular embodiments the fungi may be Saccharomyces
cerevisiae, Schizosaccharomyces pombe, Candida albicans, or Pichia
pastoris.
[0281] h. Plants
[0282] The biological material of the present invention may be a
plant or may be derived from a plant. The plant may be a Bryophyte
(e.g., mosses, liverworts, hornworts), Lycophyte (e.g., club
mosses, ground pine), Sphenophyte (e.g., horsetails), Pterophyte
(e.g., ferns), Cycadophyte (e.g., cycads), Gnetophyte (e.g.,
gnetum, ephedra, welwitschia), Coniferophyte (e.g., conifers),
Ginkophyte (e.g., ginko), or Anthophyte (e.g., flowering plants).
The Anthophyte may be a monocot or a dicot. Non-limiting examples
of monocotyledonous plants include wheat, maize, rye, rice,
turfgrass, sorghum, millet, sugarcane, lily, iris, agave, aloe,
orchids, bromeliads, and palms. Non-limiting examples of
dicotyledonous plants include tobacco, tomato, potato, soybean,
sunflower, alfalfa, canola, rose, Arabidopsis, coffee, citrus
fruits, beans, alfalfa, and cotton.
[0283] i. Protists
[0284] The biological material of the present invention may be a
Protist or may be derived from a Protist. The Protist may be a
Rhodophyte (e.g., red algea), Phaeophyte (e.g., brown algea, kelp),
Chlorophyte (e.g., green algea), Euglenophyte (e.g., euglenoids)
Myxomycot (e.g., slime molds), Oomycot (e.g., water molds, downy
mildews, potato blight), or Bacillariophyte (e.g., diatoms).
[0285] j. Prokaryotes
[0286] In certain aspects of the invention, the biological material
is a prokaryote or is derived from a prokaryote. In certain
embodiments the prokaryote is an Archaea (archaebacteria). The
archaebacteria may be, for example, a Crenarchaeota, Euryarchaeota,
Korarchaeota or Nanoarchaeota. In certain aspects the Euryarchaeota
is a Halobacteria, Methanobacteria, Methanococci, Methanomicrobia,
Methanosarcinae, Methanopyri, Archeoglobi, Thermoplasmata, or a
Thermococci. Specific, non-limiting examples of archaebacteria
include: Aeropyrum pernix, Methanococcus jannaschii, Halobacterium
marismortui, and Thermoplasma acidophilum.
[0287] In certain embodiments the prokaryote is an Eubacteria. The
Eubacteria may be, for example, an Actinobacteria, Aquificae,
Bacteroidetes, Green sulfur bacteria, Chlamydiae, Verrucomicrobia,
Chloroflexi, Chrysiogenetes, Cyanobacteria, Deferribacteres,
Deinococcus-Thermus, Dictyoglomi, Fibrobacteres/Acidobacteria,
Firmicutes, Fusobacteria, Gemmatimonadetes, Nitrospirae,
Omnibacteria, Planctomycetes, Proteobacteria, Spirochaetes,
Thermodesulfobacteria, or Thermotogae. Non-limiting examples of
Actinobacteria include bacteria of the genera Actinomyces,
Arthrobacter, Corynebacterium, Frankia, Micrococcus,
Micromonospora, Mycobacterium, Propionibacterium, and Streptomyces.
Specific examples of Actinobacteria include Mycobacterium leprae,
Mycobacterium tuberculosis, Mycobacterium avium, Corynebacterium
glutamicum, Propionibacterium acnes, and Rhodococcus equi.
[0288] Non-limiting examples of Aquificae include bacteria of the
genera Aquifex, Hydrogenivirga, Hydrogenobacter, Hydrogenobaculum,
Thermocrinis, Hydrogenothermus, Persephonella,
Sulfurihydrogenibium, Balnearium, Desulfurobacterium, and
Thermovibrio. Non-limiting examples of Firmicutes include bacteria
of the genera Bacilli, Clostridia, and Molecutes. Specific examples
of Fimmicutes include: Listeria innocua, Listeria monocytogenes,
Bacillus subtilis, Bacillus anthracis, Bacillus thuringiensis,
Staphylococcus aureus, Clostridium acetobutylicum, Clostridium
difficile, Clostridium perfringens, Mycoplasma genitalium,
Mycoplasma pneumoniae, Mycoplasma pulmonis, Streptococcus
pneumoniae, Streptococcus pyogenes, Streptococcus mutans,
Lactococcus lactis, and Enterococcus faecalis.
[0289] Non-limiting examples of Chlamydiae/Verrucomicrobia include
bacteria such as Chlamydia trachomatis, Chlamydia pneumoniae, I
Chlamydia psittaci. Non-limiting examples of Deinococcus-Thermus
include bacteria of the genera Deinococcus and Thermus.
[0290] Proteobacteria are gram-negative bacteria. Non-limiting
examples of Proteobacteria include bacteria of the genera
Escherichia, Salmonella, Vibrio, Rickettsia, Agrobacterium,
Brucella, Rhizobium, Neisseria, Bordetella, Burkholderi, Buchnera,
Yersinia, Klebsiella, Proteus, Shigella, Haemophilus, Pasteurella,
Actinobacillus, Legionella, Mannheimia, Coxiella, Aeromonas,
Francisella, Moraxella, Pseudomonas, Campylobacter, and
Helicobacter. Specific examples of Proteobacteria include:
Rickettsia conorii, Rickettsia prowazekii, Rickettsia typhi,
Ehrlichia bovis, Agrobacterium tumefaciens, Brucella melitensis,
Rhizobium rhizogenes, Neisseria meningitides, Bordetella
parapertussis, Bordetella pertussis, Burkholderi mallei,
Burkholderi pseudomallei, Neisseria gonorrhoeae, Escherichia coli,
Salmonella enterica, Salmonella typhimurium, Yersinia pestis,
Klebsiella pneumoniae, Yersinia enterocolitica, Proteus vulgaris,
Shigella flexneri, Shigella sonnei, Shigella dysenterica,
Haemophilus influenzae, Pasteurella multocida, Actinobacillus
actinomycetemcomitans, Actinobacillus pleuropneumoniae, Haemophilus
somnus, Legionella pneuinophila, Mannheimia haemolytica, Vibrio
cholerae, Vibrio parahaemolyticus, Coxiella burnetii, Aeromonas
hydrophila, Aeromonas salmonicida, Francisella tularesis, Moraxella
catarrhalis, Pseudomonas aeruginosa, Pseudomonas putida,
Campylobacter jejuni, and Helicobacter pylori.
[0291] Non-limiting examples of Spirochaetes include bacteria of
the families Brachyspiraceae, Leptospiraceae, and Spirochaetaceae.
Specific examples of Spirochaetes include Borrelia burgdorferi, and
Treponema pallidum.
[0292] 2. Different Types of Biological Matter
[0293] Methods and apparatuses of the invention can be applied to
organisms. Stasis of the organism can be induced or stasis within
cells, tissues, and/or organs of the organism can be induced.
Biological matter in which stasis can be induced that are
contemplated for use with methods and apparatuses of the invention
are limited only insofar as the comprise cells utilizing oxygen to
produce energy.
[0294] Stasis can be induced in cells, tissues, or organs involving
the heart, lung, kidney, liver, bone marrow, pancreas, skin, bone,
vein, artery, cornea, blood, small intestine, large intestine,
brain, spinal cord, smooth muscle, skeletal muscle, ovary, testis,
uterus, and umbilical cord.
[0295] Moreover, stasis can be induced in cells of the following
type: platelet, myelocyte, erythrocyte, lymphocyte, adipocyte,
fibroblast, epithelial cell, endothelial cell, smooth muscle cell,
skeletal muscle cell, endocrine cell, glial cell, neuron, secretory
cell, barrier function cell, contractile cell, absorptive cell,
mucosal cell, limbus cell (from cornea), stem cell (totipotent,
pluripotent or multipotent), unfertilized or fertilized oocyte, or
sperm.
[0296] Moreover, stasis can be induced in plants or parts of
plants, including fruit, flowers, leaves, stems, seeds, cuttings.
Plants can be agricultural, medicinal, or decorative. Induction of
stasis in plants may enhance the shelf life or pathogen resistance
of the whole or part of the plant.
[0297] Methods and apparatuses of the invention can be used to
induce stasis in in vivo biological matter. This can serve to
protect and/or preserve the biological matter or the organism
itself or to prevent damage or injury (or further damage or injury)
to them or the organism overall.
[0298] 3. Assays
[0299] Stasis can be measured by a number of ways, including by
quantifying the amount of oxygen consumed by a biological sample,
the amount of carbon dioxide produced by the sample (indirect
measurement of cellular respiration), or characterizing
motility.
[0300] To determine the rate of consumption of oxygen or the rate
of production of carbon dioxide the biological matter is placed
into a chamber that is sealed with two openings; for gas import and
export. Gas (room air or other gases) is passed into the chamber at
a given flow rate and out of the exit port to maintain
approximately 1 atmosphere of pressure in the chamber. Before and
after exposure to the chamber the gas is passed through a carbon
dioxide detector and or an oxygen detector to measure (every
second) the amount of each compound in the gas mixture. Comparison
of these values over time gives the rate of oxygen consumption or
carbon dioxide production.
II. Oxygen Antagonists and Other Active Compounds
[0301] The present invention concerns methods, compositions and
articles of manufacture involving one or more agents that can act
on biological matter so as to produce a number of effects,
including, but not limited to, inducing stasis, enhancing or
increasing survivability, reversibly inhibiting metabolism,
reducing cellular or organismal metabolism and activity, reducing
the oxygen requirement, reducing or preventing damage, preventing
ischemic damage, preventing aging or senescence, and/or a achieve a
variety of therapeutic applications discussed herein. It certain
embodiments, the agents are qualified as "active compounds."
[0302] In some embodiments, the agent is an oxygen antagonist,
which may act directly or indirectly. Oxygen metabolism is a
fundamental requirement for life in aerobic metazoans. Aerobic
respiration accounts for the vast majority of energy production in
most animals and also serves to maintain the redox potential
necessary to carry out important cellular reactions. In hypoxia,
decreased oxygen availability results in inefficient transfer of
electrons to molecular oxygen in the final step of the electron
transport chain. This inefficiency results in both a decrease in
aerobic energy production and an increase in the production of
damaging free radicals, mainly due to the premature release of
electrons at complex III and the formation of O.sub.2-- by
cytochrome oxidase (Semenza, 1999). Limited energy supplies and
free radical damage can interfere with essential cellular processes
such as protein synthesis and maintenance of membrane polarities
(Hochachka et al., 1996), and will ultimately lead to cell
death.
[0303] In other embodiments, the agent is a protective metabolic
agent. Metabolism is generally understood as referring to chemical
processes (in a cell or organism) that are required for life; they
involve a variety of reactions to sustain energy production and
synthesize (anabolism) and break down (catabolism) complex
molecules.
[0304] In certain embodiments of the invention, an active compound
has a chemical structure as set forth as Formula I or IV described
herein, or is a precursor of Formula I or IV.
[0305] A variety of chemical structures and compounds are described
herein. The following definitions apply to terms used to described
these structures and compounds discussed herein:
[0306] "Alkyl," where used, either alone or within other terms such
as "arylalkyl", "aminoalkyl", "thioalkyl" "cyanoalkyl" and
"hydroxyalkyl", refers to linear or branched radicals having one to
about twenty carbon atoms. The term "lower alkyl" refers to
C.sub.1-C.sub.6 alkyl radicals. As used herein the term alkyl
includes those radicals that are substituted with groups such as
hydroxy, halo (such as F, Cl, Br, I), haloalkyl, alkoxy,
haloalkoxy, alkylthio, cyano, isocyano, carboxy (--COOH),
alkoxycarbonyl, (--COOR), acyl, acyloxy, amino, alykamino, urea
(--NHCONHR), thiol, alkylthio, sulfoxy, sulfonyl, arylsulfonyl,
alkylsulfonyl, sulfonamido, arylsulfonamido, heteroaryl,
heterocyclyl, heterocycloalkyl, amidyl, alkylimino carbonyl,
amidino, guanidono, hydrazino, hydrazide, sodium sulfonyl
(--SO.sub.3Na), sodium sulfonylalkyl (--RSO.sub.3Na). Examples of
such radicals include, but are not limited to, methyl, ethyl,
n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl,
pentyl, iso-amyl, hexyl and the like.
[0307] "Hydroxyalkyl" refers to an alkyl radical, as defined
herein, substituted with one or more hydroxyl radicals. Examples of
hydroxyalkyl radicals include, but are not limited to,
hydroxymethyl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl,
2-hydroxybutyl, 3-hydroxybutyl, 4-hydroxybutyl,
2,3-dihydroxypropyl, 1-(hydroxymethyl)-2-hydroxyethyl,
2,3-dihydroxybutyl, 3,4-dihydroxybutyl, and
2-(hydroxymethyl)-3-hydroxypropyl, and the like.
[0308] "Arylalkyl" refers to the radical R'R-- wherein an alkyl
radical, "R" is substituted with an aryl radical "R'." Examples of
arylalkyl radicals include, but are not limited to, benzyl,
phenylethyl, 3-phenylpropyl, and the like.
[0309] "Aminoalkyl" refers to the radical H.sub.2NR'--, wherein an
alkyl radical is substituted with am amino radical. Examples of
such radicals include aminomethyl, amino ethyl, and the like.
"Alkylaminoalkyl" refers to an alkyl radical substituted with an
alkylamino radical.
[0310] "Alkylsulfonamido" refers to a sulfonamido group
(--S(O).sub.2--NRR') appended to an alkyl group, as defined
herein.
[0311] "Thioalkyl" refers to wherein an alkyl radical is
substituted with one or more thiol radicals. "Alkylthioalkyl"
refers to wherein an alkyl radical is substituted with one or more
alkylthio radicals. Examples include, but are not limited to,
methylthiomethyl, ethylthioisopropyl, and the like. Arylthioalkyl"
refers to wherein an alkyl radical, as herein defined, is
substituted with one or more arylthio radicals.
[0312] "Carboxyalkyl" refers to the radicals --RCO.sub.2H, wherein
an alkyl radical is substituted with a carboxyl radical. Example
include, but are not limited to, carboxymethyl, carboxyethyl,
carboxypropyl, and the like.
[0313] "Alkylene" refers to bridging alkyl radicals.
[0314] The term "alkenyl" refers to an unsaturated, acyclic
hydrocarbon radical in so much as it contains at least one double
bond. Such alkenyl radicals contain from about 2 to about 20 carbon
atoms. The term "lower alkenyl" refers to C.sub.1-C.sub.6 alkenyl
radicals. As used herein, the term alkenyl radicals includes those
radicals substituted as for alkyl radicals. Examples of suitable
alkenyl radicals include propenyl, 2-chloropropenyl, buten-1-yl,
isobutenyl, pent-1-en-1-yl, 2-2-methyl-1-buten-1-yl,
3-methyl-1-buten-1-yl, hex-2-en-1-yl, 3-hydroxyhex-1-en-1-yl,
hept-1-en-1-yl, and oct-1-en-1-yl, and the like.
[0315] The term "alkynyl" refers to an unsaturated, acyclic
hydrocarbon radical in so much as it contains one or more triple
bonds, such radicals containing about 2 to about 20 carbon atoms.
The term "lower alkynyl" refers to C.sub.1-C.sub.6 alkynyl
radicals. As used herein, the term alkynyl radicals includes those
radicals substituted as for alkyl radicals. Examples of suitable
alkynyl radicals include ethynyl, propynyl, hydroxypropynyl,
but-1-yn-1-yl, but-1-yn-2-yl, pent-1-yn-1-yl, pent-1-yn-2-yl,
4-methoxypent-1-yn-2-yl, 3-methylbut-1-yn-1-yl, hex-1-yn-1-yl,
hex-1-yn-2-yl, hex-1-yn-3-yl, 3,3-dimethyl-1-butyn-1-yl radicals
and the like
[0316] "Alkoxy," refers to the radical R'O--, wherein R' is an
alkyl radical as defined herein. Examples include, but are not
limited to, methoxy, ethoxy, propoxy, butoxy, isopropoxy,
tert-butoxy alkyls, and the like. Alkoxyalkyl" refers to alkyl
radicals substituted by one or more alkoxy radicals. Examples
include, but are not limited to, methoxymethyl, ethoxyethyl,
methoxyethyl, isopropoxyethyl, and the like.
[0317] "Alkoxycarbonyl" refers to the radical R--O--C(O)--, wherein
R is an alkyl radical as defined herein. Examples of alkoxycarbonyl
radicals include, but are not limited to, methoxycarbonyl,
ethoxycarbonyl, sec-butoxycarbonyl, isoprpoxycarbonyl, and the
like. Alkoxythiocarbonyl refers to R--O--C(S)--.
[0318] "Aryl" refers to the monovalent aromatic carbocyclic radical
consisting of one individual ring, or one or more fused rings in
which at least one ring is aromatic in nature, which can optionally
be substituted with one or more, preferably one or two,
substituents such as hydroxy, halo (such as F, Cl, Br, I),
haloalkyl, alkoxy, haloalkoxy, alkylthio, cyano, carboxy (--COOH),
alkoxycarbonyl, (--COOR), acyl, acyloxy, amino, alykamino, urea
(--NHCONHR), thiol, alkylthio, sulfoxy, sulfonyl, arylsulfonyl,
alkylsulfonyl, sulfonamido, arylsulfonamido, heteroaryl,
heterocyclyl, heterocycloalkyl, amidyl, alkylimino carbonyl,
amidino, guanidono, hydrazino, hydrazide, sodium sulfonyl
(--SO.sub.3Na), sodium sulfonylalkyl (--RSO.sub.3Na), unless
otherwise indicated. Alternatively two adjacent atoms of the aryl
ring may be substituted with a methylenedioxy or ethylenedioxy
group. Examples of aryl radicals include, but are not limited to,
phenyl, naphthyl, biphenyl, indanyl, anthraquinolyl,
tert-butyl-phenyl, 1,3-benzodioxolyl, and the like.
[0319] "Arylsulfonamido" refers to a sulfonamido group, as defined
herein, appended to an aryl group, as defined herein.
[0320] "Thioaryl" refers to an aryl group substituted with one or
more thiol radicals.
[0321] "Alkylamino" refers to amino groups that are substituted
with one or two alkyl radicals. Examples include monosubstituted
N-alkylamino radicals and N,N-dialkylamino radicals. Examples
include N-methylamino, N-ethylamino, N,N-dimeythylamino
N,N-diethylamino, N-methyl, N-ethyl-amino, and the like.
[0322] "Aminocarbonyl" refers to the radical H.sub.2NCO--.
"Aminocarbonyalkyl" refers to the substitution of an alkyl radical,
as herein defined, by one or more aminocarbonyl radicals.
[0323] "Amidyl" refers to RCO--NH--, wherein R is a H or alkyl,
aryl, or heteroaryl, as defined herein.
[0324] "Imino carbonyl" refers to a carbon radical having two of
the four covalent bond sites shared with an imino group. Examples
of such imino carbonyl radicals include, for example, C.dbd.NH,
C.dbd.NCH.sub.3, C.dbd.NOH, and C.dbd.NOCH.sub.3. The term
"alkylimino carbonyl" refers to an imino radical substituted with
an alkyl group, The term "amidino" refers to a substituted or
unsubstituted amino group bonded to one of two available bonds of
an iminocarbonyl radical. Examples of such amidino radicals
include, for example, NH.sub.2--C.dbd.NH,
NH.sub.2--C.dbd.NCH.sub.3, NH--C.dbd.NOCH.sub.3 and
NH(CH.sub.3)--C.dbd.NOH. The term "guanidino" refers to an amidino
group bonded to an amino group as defined above where said amino
group can be bonded to a third group. Examples of such guanidino
radicals include, for example, NH.sub.2--C(NH)--NH--,
NH.sub.2--C(NCH.sub.3)--NH--, NH.sub.2--C(NOCH.sub.3)--NH--, and
CH.sub.3NH--C(NOH)--NH--. The term "hydrazino" refers to
--NH--NRR', where R and R' are independently hydrogen, alkyl and
the like. "Hydrazide" refers to --C(.dbd.O)--NH--NRR'.
[0325] The term "heterocyclyl" refers to saturated and partially
saturated heteroatom-containing ring-shaped radicals having from 4
through 15 ring members, herein referred to as "C.sub.4-C.sub.15
heterocyclyl" selected from carbon, nitrogen, sulfur and oxygen,
wherein at least one ring atom is a heteroatom. Heterocyclyl
radicals may contain one, two or three rings wherein such rings may
be attached in a pendant manner or may be fused. Examples of
saturated heterocyclic radicals include saturated 3 to 6-membered
heteromonocylic group containing 1 to 4 nitrogen atoms[e.g.
pyrrolidinyl, imidazolidinyl, piperidino, piperazinyl, etc];
saturated 3 to 6-membered heteromonocyclic group containing 1 to 2
oxygen atoms and 1 to 3 nitrogen atoms [e.g. morpholinyl, etc.];
saturated 3 to 6-membered heteromonocyclic group containing 1 to 2
sulfur atoms and 1 to 3 nitrogen atoms [e.g., thiazolidinyl, etc.].
Examples of partially saturated heterocyclyl radicals include
dihydrothiophene, dihydropyran, dihydrofuran and dihydrothiazole.
Non-limiting examples of heterocyclic radicals include
2-pyrrolinyl, 3-pyrrolinyl, pyrrolindinyl, 1,3-dioxolanyl,
2H-pyranyl, 4H-pyranyl, piperidinyl, 1,4-dioxanyl, morpholinyl,
1,4-dithianyl, thiomorpholinyl, and the like. Such heterocyclyl
groups may be optionally substituted with groups such as
substituents such as hydroxy, halo (such as F, Cl, Br, I),
haloalkyl, alkoxy, haloalkoxy, alkylthio, cyano, carboxy (--COOH),
alkoxycarbonyl, (--COOR), acyl, acyloxy, amino, alykamino, urea
(--NHCONHR), thiol, alkylthio, sulfoxy, sulfonyl, arylsulfonyl,
alkylsulfonyl, sulfonamido, arylsulfonamido, heteroaryl,
heterocyclyl, heterocycloalkyl, amidyl, alkylimino carbonyl,
amidino, guanidono, hydrazino, hydrazide, sodium sulfonyl
(--SO.sub.3Na), sodium sulfonylalkyl (--RSO.sub.3Na).
[0326] "Hetroaryl" refers to monovalent aromatic cyclic radicals
having one or more rings, preferably one to three rings, of four to
eight atoms per ring, incorporating one or more heteroatoms,
preferably one or two, within the ring (chosen from nitrogen,
oxygen, or sulfur), which can optionally be substituted with one or
more, preferably one or two substituents selected from substituents
such as hydroxy, halo (such as F, Cl, Br, I), haloalkyl, alkoxy,
haloalkoxy, alkylthio, cyano, carboxy (--COOH), alkoxycarbonyl,
(--COOR), acyl, acyloxy, amino, alykamino, urea (--NHCONHR), thiol,
alkylthio, sulfoxy, sulfonyl, arylsulfonyl, alkylsulfonyl,
sulfonamido, arylsulfonamido, heteroaryl, heterocyclyl,
heterocycloalkyl, amidyl, alkylimino carbonyl, amidino, guanidono,
hydrazino, hydrazide, sodium sulfonyl (--SO.sub.3Na), sodium
sulfonylalkyl (--RSO.sub.3Na), unless otherwise indicated. Examples
of heteroaryl radicals include, but are not limited to, imidazolyl,
oxazolyl, thiazolyl, pyrazinyl, thienyl, furanyl, pyridinyl,
quinolinyl, isoquinolinyl, benzofuryl, benzothiophenyl,
benzothiopyranyl, benzimidazolyl, benzoxazolyl, benzothiazolyl,
benzopyranyl, indazolyl, indolyl, isoindolyl, quinolinyl,
isoquinolinyl, naphthyridinyl, benezenesulfonyl-thiophenyl, and the
like.
[0327] "Heteroaryloxy" refers to heteroaryl radicals attached to an
oxy radical. Examples of such radicals include, but are not limited
to, 2-thiophenyloxy, 2-pyrimidyloxy, 2-pyridyloxy, 3-pyridyloxy,
4-pyridyloxy, and the like
[0328] "Heteroaryloxyalkyl" refers to alkyl radicals substituted
with one or more heteroaryloxy radicals. Examples of such radicals
include 2-pyridyloxymethyl, 3-pyridyloxyethyl, 4-pyridyloxymethyl,
and the like.
[0329] "Cycloalkyl" refers to monovalent saturated carbocyclic
radicals consisting of one or more rings, typically one or two
rings, of three to eight carbons per ring, which can typically be
substituted with one or more, substitutents hydroxy, halo (such as
F, Cl, Br, I), haloalkyl, alkoxy, haloalkoxy, alkylthio, cyano,
carboxy (--COOH), alkoxycarbonyl, (--COOR), acyl, acyloxy, amino,
alykamino, urea (--NHCONHR), thiol, alkylthio, sulfoxy, sulfonyl,
arylsulfonyl, alkylsulfonyl, sulfonamido, arylsulfonamido,
heteroaryl, heterocyclyl, heterocycloalkyl, amidyl, alkylimino
carbonyl, amidino, guanidono, hydrazino, hydrazide, sodium sulfonyl
(--SO.sub.3Na), sodium sulfonylalkyl (--RSO.sub.3Na), unless
otherwise indicated. Examples of cycloalkyl radicals include, but
are not limited to, cyclopropyl, cyclobutyl, 3-ethylcyclobutyl,
cyclopentyl, cycloheptyl, and the like. "Cycloalkenyl" refers to
radicals having three to ten carbon atoms and one or more
carbon-carbon double bonds. Typical cycloalkenyl radicals have
three to seven carbon atoms. Examples include cyclobutenyl,
cyclopentenyl, cyclohexenyl, cycloheptenyl, and the like
"Cycloalkenylalkyl" refers to radicals wherein an alkyl radical, as
defined herein, is substituted by one or more cycloalkenyl
radicals.
[0330] "Cylcoalkoxy" refers to cycloalkyl radicals attached to an
oxy radical. Examples include, but are not limited to, cyclohexoxy,
cyclopentoxy and the like.
[0331] "Cylcoalkoxyalkyl" refers to alkyl radicals substituted one
or more cycloalkoxy radicals. Examples include cyclohexoxyethyl,
cyclopentoxymethyl, and the like. Sulfinyl" refers to --S(O)--.
[0332] "Sulfonyl" refers to --S(O).sub.2--, wherein "alkylsulfonyl"
refers to a sulfonyl radical substituted with an alkyl radical,
RSO.sub.2--, arylsulfonyl refers to aryl radicals attached to a
sulfonyl radical. "Sulfonamido" refers to --S(O).sub.2--NRR'.
[0333] "Sulfonic acid" refers to --S(O).sub.2OH. "Sulfonic ester"
refers to --S(O).sub.2OR, wherein R is a group such as an alkyl as
in sulfonic alkyl ester.
[0334] "Thio" refers to --S--. "Alkylthio" refers to RS-- wherein a
thiol radical is substituted with an alkyl radical R. Examples
include methylthio, ethylthio, butlythio, and the like. "Arylthio"
refers to R'S--, wherein a thio radical is substituted with an aryl
radical, as herein defined. "Examples include, but are not limited
to, phenylthio, and the like. Examples include, but are not limited
to, phenylthiomethyl and the like. "Alkylthiosulfonic acid" refers
to the radical HO.sub.3SR'S--, wherein an alkylthioradical is
substituted with a sulfonic acid radical.
[0335] "Thiosulfenyl" refers to --S--SH.
[0336] "Acyl", alone or in combination, refers to a carbonyl or
thionocarbonyl group bonded to a radical selected from, for
example, hydrido, alkyl, alkenyl, alkynyl, haloalkyl, alkoxy,
alkoxyalkyl, haloalkoxy, aryl, heterocyclyl, heteroaryl,
alkylsulfinylalkyl, alkylsulfonylalkyl, aralkyl, cycloalkyl,
cycloalkylalkyl, cycloalkenyl, alkylthio, arylthio, amino,
alkylamino, dialkylamino, aralkoxy, arylthio, and alkylthioalkyl.
Examples of "acyl" are formyl, acetyl, benzoyl, trifluoroacetyl,
phthaloyl, malonyl, nicotinyl, and the like.
[0337] The term "acylthiol" and "acyldisulfide" refers to the
radicals RCOS- and RCOSS- respectively.
[0338] The term "thiocarbonyl" refers to the compounds and moieties
which contain a carbon connected with a double bond to a sulfur
atom --C(.dbd.S)--. "Alkylthiocarbonyl" refers to wherein a
thiocarbonyl group is substituted with an alkyl radical, R. as
defined herein, to form the monovalent radical RC(.dbd.S)--.
"Aminothiocarbonyl" refers to a thiocarbonyl group substituted with
an amino group, NH.sub.2C(.dbd.S)--.
[0339] "Carbonyloxy" refers to --OCOR.
[0340] "Alkoxycarbonyl" refers to --COOR.
[0341] "Carboxyl" refers to --COOH.
[0342] For those compounds with stereoisomers, all stereoisomers
thereof, including cis/trans geometric isomers, diastereomers and
the individual enantiomers are contemplated
[0343] A. Carbon Monoxide
[0344] Carbon monoxide (CO) is a colorless, odorless, and tasteless
gas that can be toxic to animals, including humans. According to
the Center for Disease Control, more than 450 people
unintentionally die from carbon monoxide each year.
[0345] It can be toxic to organisms whose blood carries oxygen to
sustain its survival. It may be poisonous by entering the lungs
through normal breathing and displacing oxygen from the
bloodstream. Interruption of the normal supply of oxygen
jeopardizes the functions of the heart, brain and other vital
functions of the body. However, the use of carbon monoxide for
medical applications is being explored (Ryter et al., 2004).
[0346] At amounts of 50 parts per million (ppm), carbon monoxide
presents no symptoms to humans exposed to it. However, at 200 ppm,
within two-three hours the carbon monoxide can cause a slight
headache; at 400 ppm, within one to two hours it can cause a
frontal headache that may become widespread within three hours;
and, at 800 ppm it can cause dizziness, nausea, and/or convulsions
within 45 minutes, and render the subject insensible within two
hours. At levels of around 1000 ppm, an organism can expire after
exposure for more than around 1-2 minutes.
[0347] Because of the well-known and well-documented toxic effects
of carbon monoxide to an organism, it is thus surprising and
unexpected that carbon monoxide can be used to induce stasis of
and/or help preserve live biological samples. It is thus
contemplated that carbon monoxide can be used for inducing stasis
in isolated biological matter, such as blood-free biological matter
(because of the effects that carbon monoxide has with respect to
hemoglobin, which is a separate pathway than the one involved in
inducing stasis).
[0348] In addition to exposure to carbon monoxide either to induce
stasis or to limit or prevent any damage caused by a
stasis-inducing agent, the invention contemplates that carbon
monoxide may be used in combination with agents or methods that
assist in the preservation and/or transplantation/grafting process
of biological materials.
[0349] B. Chalcogenide Compounds
[0350] Compounds containing a chalcogen element; those in Group 6
of the periodic table, but excluding oxides, are commonly termed
"chalcogenides" or "chalcogenide compounds (used interchangeably
herein). These elements are sulfur (S), selenium (Se), tellurium
(Te) and polonium (Po). Common chalcogenides contain one or more of
S, Se and Te, in addition to other elements. Chalcogenides include
elemental forms such as micronized and/or nanomilled particles of S
and Se. Chalcogenide compounds can be employed as reducing
agents.
[0351] The present inventor, though not bound by the following
theory, believes that the ability of chalcogenides to induce stasis
in cells, and to permit modulation of core body temperature in
animals, stems from the binding of these molecules to cytochrome
oxidase. In so doing, chalcogenides inhibit or reduce the activity
of oxidative phosphorylation. The ability of chalcogenides to block
autonomous thermoregulation, i.e., to permit core body temperatures
of "warm-blooded" animals to be manipulated through control of
environmental temperatures, is believed to stem from the same
mechanism as set forth above--binding to cytochrome oxidase, and
blocking or reducing the activity of oxidative phosphorylation.
Chalcogenides may be provided in liquid as well as gaseous
forms.
[0352] Chalcogenides can be toxic, and at some levels lethal, to
mammals. In accordance with the present invention, it is
anticipated that the levels of chalcogenide should not exceed
lethal levels in the appropriate environment. Lethal levels of
chalcogenides may be found, for example in Material Safety Data
Sheets for each chalcogenide or from information sheets available
from the Occupational Safety and Health Administration (OSHA) of
the US Government.
[0353] While carbon monoxide and chalcogenide compounds can both
induce stasis by acting as an oxygen antagonist, they have
different toxic effects that are separate from their abilities to
induce stasis. Moreover, the concentrations needed to mediate a
stasis effect are different because of the different affinities of
cytochrome oxidase. While the affinity of cytochrome oxidase for
oxygen is about 1:1 as compared to carbon monoxide, the affinity
for H.sub.2S appears on the order of about 300:1 as compared to
oxygen. This impacts what toxic effects are observed with a
stasis-inducing concentration. Thus, it is contemplated that
chalcogenide compounds are particularly suited for inducing stasis
of biological matter in whole organisms and of whole organisms.
[0354] It also may prove useful to provide additional stimuli to a
biological matter before withdrawing the chalcogenide. In
particular, it is envisioned that one may subject an animal to
increased ambient temperature prior to removing the source of
chalcogenide.
[0355] 1. H.sub.2S and Other Sulfur Containing Compounds
[0356] Hydrogen sulfide (H.sub.2S) is a potentially toxic gas that
is often associated with petrochemical and natural gas, sewage,
paper pulp, leather tanning, and food processing. The primary
effect, at the cellular level, appears to be inhibition of
cytochrome oxidase and other oxidative enzymes, resulting in
cellular hypoxia. Exposure to extreme levels (500 ppm) results in
sudden collapse and unconsciousness, a so-called "knockdown"
effect, followed by recovery. Post-exposure effects may persist for
years, and include loss of coordination, memory loss, motor
dysfunction, personality changes, hallucination and insomnia.
[0357] Most contact with H.sub.2S, however, occurs well below such
acute toxicity levels. Nonetheless, there is general concern over
longterm contact at sub-acute levels. Some reports exist indicating
persistent impairments in balance and memory, as well as altered
sensory motor functions may occur in humans following chronic
low-level H.sub.2S exposure. Kilburn and Warshaw (1995); Kilburn
(1999). Others have reported that perinatal exposure of rats to low
(20 or 50 ppm) H.sub.2S for 7 hours per day from gestation through
post-natal day 21 resulted in longer dendritic branches with
reduced aborization of cerebellar Purkinje cells. Other neurologic
defects associated with relatively low levels of H.sub.2S include
altered brain neurotransmitter concentrations and altered
neurologic responses, such as increased hippocampal theta EEG
activity.
[0358] Behavioral toxicity was studied in rats exposed to moderate
levels of H.sub.2S. The results showed that H.sub.2S inhibits
discriminated avoidance responses immediately after the end of the
exposure (Higuchi and Fukamachi, 1997), and also interferes with
the ability of rats to learn a baited radial arm maze task (Partlo
et al., 2001). In another perinatal study using 80 ppm H.sub.2S, no
neuropathological effects or altered motor activity, passive
avoidance, or acoustic startle response in exposed rat pups was
seen. Dorman et al. (2000). Finally, Struve et al. (2001) exposed
rats to H.sub.2S by gas at various levels for 3 hours per day on
five consecutive days. Significant reductions in motor activity,
water maze performance and body temperature following exposure to
80 ppm or greater H.sub.2S were observed. Taken together, these
reports indicate that H.sub.2S can have a variety of effects on the
biochemistry of mammalian tissues, but there is no clear pattern of
response in terms of behavior.
[0359] Once dissolved in plasma, H.sub.2S will be involved in a
series of chemical reactions. The chemical reactions are: (1) the
dissociation of the molecular H.sub.2S to form the bisulfide ion,
(2) the dissociation of the bisulfide ion to the sulfide ion, and
(3) the self ionization of water. The reactions are given
below:
H.sub.2S.sub.(aq)HS.sub.(aq).sup.-+H.sub.(aq).sup.+
HS.sub.(aq).sup.-S.sub.(aq).sup.-1+H.sub.(aq).sup.+
H.sub.2OH.sub.(aq).sup.++OH.sub.(aq).sup.-
[0360] Using the equilibrium constants K.sub.1=1.039 E-07,
K.sub.2=6.43 E.sup.-16 and K.sub.w=1.019 E.sup.-14, at pH 7.4 the
calculated amount of the different species relative to the total S
concentration are approximately 23% H.sub.2S and 77% HS.sup.-,
while the amount of S.sup.2- tends to zero.
[0361] The inventor uses an extractive alkylation technique coupled
with gas chromatography and mass specific detection to quantify
hydrogen sulfide (adapted from Hyspler et al., 2002). This method
involves firstly adding a 50 .mu.L sample of blood, serum or tissue
extract that has been diluted in nitrogen purged deoxygenated water
to a concentration of 1 mg/mL, together with 150 .mu.L of a
reaction buffer consisting of 5 mM benzalkonium chloride (BZK) in a
saturated borate buffer. Added to this is first, 100 .mu.L of a 15
.mu.M solution of 4-chloro-benzyl methyl sulfide (4CBMS) in ethyl
acetate and then 100 .mu.L of a 20 mM solution of
pentafluorobenzylbromide (PFBBr) in toluene. This solution is then
sealed and incubated at 55.degree. C. with rotation or shaking for
2 hr. After this incubation period, 200 .mu.L of a saturated
solution of KH.sub.2PO.sub.4 is then added, and the organic phase
is removed and analyzed by gas chromatography and mass specific
detection according to the methods described in Hyspler et al.,
2002. These measurements are then compared to a standard curve
generated using the same method described above, beginning with
known standard concentrations ranging from 1 .mu.M to 1 mM of
Na.sub.2S prepared in nitrogen purged deoxygenated H.sub.2O, in
order to determine the concentration of endogenous hydrogen sulfide
levels. In order to analyze bound and/or oxidized sulfide levels,
the same method is applied, except that a denaturing/reducing
reaction buffer is used, which consists of 5 mM BZK with 1%
tetraethylammonium hydroxide (TEAH) and 1 mM
tris(2-carboxyethyl)-phosphine hydrochloride (TCEP) in saturated
borate buffer, instead of the reaction buffer described above.
[0362] Typical levels of hydrogen sulfide contemplated for use in
accordance with the present invention include values of about 1 to
about 150 ppm, about 10 to about 140 ppm, about 20 to about 130
ppm, and about 40 to about 120 ppm, or the equivalent oral,
intravenous or transdermal dosage thereof. Other relevant ranges
include about 10 to about 80 ppm, about 20 to about 80 ppm, about
10 to about 70 ppm, about 20 to about 70 ppm, about 20 to about 60
ppm, and about 30 to about 60 ppm, or the equivalent oral,
intravenous or transdermal thereof. It also is contemplated that,
for a given animal in a given time period, the chalcogenide
atmosphere should be reduced to avoid a potentially lethal build up
of chalcogenide in the subject. For example, an initial
environmental concentration of 80 ppm may be reduced after 30 min
to 60 ppm, followed by further reductions at 1 hr (40 ppm) and 2
hrs (20 ppm).
[0363] a. H.sub.2S Precursors
[0364] The present invention also concerns the use of compounds and
agents that can yield H.sub.2S under certain conditions, such as
upon exposure, or soon thereafter, to biological matter. It is
contemplated that such precursors yield H.sub.2S upon one or more
enzymatic or chemical reactions.
[0365] 3. Other Chalcogenides
[0366] In certain embodiments, the reducing agent structure
compound is dimethylsulfoxide (DMSO), dimethylsulfide (DMS),
methylmercaptan (CH.sub.3SH), mercaptoethanol, thiocyanate,
hydrogen cyanide, methanethiol (MeSH), or CS.sub.2. In particular
embodiments, the oxygen antagonist is CS.sub.2, MeSH, or DMS.
Compounds on the order of the size of these molecules are
particularly contemplated (that is, within about 50% of their
molecular weights).
[0367] Additional compounds that are envisioned as useful for
inducing stasis include, but are not limited to, the following
structures, many of which are readily available and known to those
of skill in the art (identified by CAS number): 104376-79-6
(Ceftriaxone Sodium Salt); 105879-42-3; 1094-08-2 (Ethopropatine
HCl); 1098-60-8 (Triflupromazine HCl); 111974-72-2; 113-59-7;
113-98-4 (Penicillin G K.sup.+); 115-55-9; 1179-69-7; 118292-40-3;
119478-56-7; 120138-50-3; 121123-17-9; 121249-14-7; 1229-35-2;
1240-15-9; 1257-78-9 (Prochlorperazine Edisylate Salt);
128345-62-0; 130-61-0 (Thioridazine HCl) 132-98-9 (Penicillin V
K.sup.+); 13412-64-1 (Dicloxacillin Na.sup.+Hydrate); 134678-17-4;
144604-00-2; 146-54-3; 146-54-5 (Fluphenazine 2HCl); 151767-02-1;
159989-65-8; 16960-16-0 (Adrenocorticotropic Hormone Fragment
1-24); 1982-37-2; 21462-39-5 (Clindamycin HCl); 22189-31-7;
22202-75-1; 23288-49-5 (Probucol); 23325-78-2; 24356-60-3
(Cephapirin); 24729-96-2 (Clindamycin); 25507-04-4; 26605-69-6;
27164-46-1 (Cefazolin Na.sup.+); 2746-81-8; 29560-58-8; 2975-34-0;
32672-69-8 (Mesoridazine Benzene Sulfonate); 32887-01-7; 33286-22-5
((+)-cis-Diltiazem HCl); 33564-30-6 (Cefoxitin Na.sup.+); 346-18-9;
3485-14-1; 3511-16-8; 37091-65-9 (Azlocillin Na.sup.+); 37661-08-8;
3819-00-9; 38821-53-3 (Cephradine); 41372-02-5; 42540-40-9
(Cefamandole Nafate); 4330-99-8 (Trimeprazine hemi-(+)-tartrate
Salt); 440-17-5 Trifluoperazine 2HCl; 4697-14-7 (Ticarcillin
2Na.sup.+); 4800-94-6 (Carbenicillin 2Na.sup.+); 50-52-2; 50-53-3;
5002-47-1; 51481-61-9 (Cimetidine); 52239-63-1
(6-propyl-2-thiouracil); 53-60-1 (Promazine HCl); 5321-32-4;
54965-21-8 (Albendazole); 5591-45-7 (Thiothixene); 56238-63-2
(Cefuroxime Na.sup.+); 56796-39-5 (Cefmetazole Na.sup.+);
5714-00-1; 58-33-3 (Promethazine HCl); 58-38-8; 58-39-9
(Perphenazine); 58-71-9 Cephalothin Na.sup.+); 59703-84-3
(Piperacillin Na.sup.+); 60-99-1 (Methotrimeprazine Maleate Salt);
60925-61-3; 61270-78-8; 6130-64-9 (Penicillin G Procaine Salt
Hydrate); 61318-91-0 Sulconazole Nitrate Salt); 61336-70-7
Amoxicillin Trihydrate); 62893-20-3 Cefoperazone Na.sup.+);
64485-93-4 (Cefotaxime Na.sup.+); 64544-07-6; 64872-77-1;
64953-12-4 Moxalactam Na.sup.+); 66104-23-2 (Pergolide Mesylate
Salt); 66309-69-1; 66357-59-3 (Ranitidine HCl); 66592-87-8
(Cefodroxil); 68401-82-1; 69-09-0 (Chlorpromazine HCl); 69-52-3
(Ampicillin Na.sup.+); 69-53-4 (Ampicillin); 69-57-8 Penicillin G
Na.sup.+); 70059-30-2; 70356-03-5; 7081-40-5; 7081-44-9
(Cloxacillin Na+ H.sub.2O); 7177-50-6 Nafcillin Na+ H.sub.2O);
7179-49-9; 7240-38-2 (Oxacillin Na H.sub.2O); 7246-14-2;
74356-00-6; 74431-23-5; 74849-93-7; 75738-58-8; 76824-35-6
(Famotidine); 76963-41-2; 79350-37-1; 81129-83-1; 84-02-6
(Prochlorperazine Dimaleate Salt); 87-08-1
(Phenoxymethylpenicillinic Acid); 87239-81-4; 91-33-8
(Benzthiazide); 91832-40-5; 94841-17-5; 99294-94-7; 154-42-7
(6-Thioguanine); 36735-22-5; 536-33-4 (Ethionamide); 52-67-5
(D-Penicillamine); 304-55-2 (Meso-2,3-Dimercaptosuccinic Acid);
59-52-9 2,3-Dimercapto.sup.+ propanol 6112-76-1 (6-mercaptopurine);
616-91-1 (N-acetyl-L-cysteine); 62571-86-2 (Captopril); 52-01-7
(spironolactone); and, 80474-14-2 (fluticasone propionate). Further
compounds that are contemplated as possibly useful for stasis
include those with the chemical structure of Formulas I or IV.
[0368] C. Other Antagonists or Active Compounds and Related
Environmental Conditions
[0369] 1. Hypoxia and Anoxia
[0370] Hypoxia is a common natural stress and several well
conserved responses exist that facilitate cellular adaptation to
hypoxic environments. To compensate for the decrease in the
capacity for aerobic energy production in hypoxia, the cell must
either increase anaerobic energy production or decrease energy
demand (Hochachka et al., 1996). Examples of both of these
responses are common in metazoans and the particular response used
depends, in general, on the amount of oxygen available to the
cell.
[0371] In mild hypoxia, oxidative phosphorylation is still
partially active, so some aerobic energy production is possible.
The cellular response to this situation, which is mediated in part
by the hypoxia-inducible transcription factor, HIF-1, is to
supplement the reduced aerobic energy production by upregulating
genes involved in anaerobic energy production, such as glycolytic
enzymes and glucose transporters (Semenza, 2001; Guillemin et al.,
1997). This response also promotes the upregulation of antioxidants
such as catylase and superoxide dismutase, which guard against free
radical-induced damage. As a result, the cell is able to maintain
near normoxic levels of activity in mild hypoxia.
[0372] In an extreme form of hypoxia, referred to as
"anoxia"--defined here as <0.001 kPa O.sub.2--oxidative
phosphorylation ceases and thus the capacity to generate energy is
drastically reduced. In order to survive in this environment, the
cell must decrease energy demand by reducing cellular activity
(Hochachka et al., 2001). For example, in turtle hepatocytes
deprived of oxygen, a directed effort by the cell to limit
activities such as protein synthesis, ion channel activity, and
anabolic pathways results in a 94% reduction in demand for ATP
(Hochachka et al., 1996). In zebrafish (Danio rerio) embryos,
exposure to anoxia leads to a complete arrest of the heartbeat,
movement, cell cycle progression, and developmental progression
(Padilla et al., 2001). Similarly, C. elegans respond to anoxia by
entering into suspended animation, in which all observable
movement, including cell division and developmental progression,
ceases (Padilla et al., 2002; Van Voorhies et al., 2000). C.
elegans can remain suspended for 24 hours or more and, upon return
to normoxia, will recover with high viability. This response allows
C. elegans to survive the hypoxic stress by reducing the rate of
energetically expensive processes and preventing the occurrence of
damaging, irrevocable events such as aneuploidy (Padilla et al.,
2002; Nystul et al., 2003).
[0373] One recently discovered response is the hypoxia-induced
generation of carbon monoxide by heme oxygenase-1 (Dulak et al.,
2003). Endogenously produced carbon monoxide can activate signaling
cascades that mitigate hypoxic damage through anti-apoptotic
(Brouard et al., 2003) and anti-inflammatory (Otterbein et al.,
2000) activity, and similar cytoprotective effects can be achieved
in transplant models by perfusion with exogenous carbon monoxide
(Otterbein et al, 2003; Amersi et al., 2002). At higher
concentrations, carbon monoxide competes with oxygen for binding to
iron-containing proteins, such as mitochondrial cytochromes and
hemoglobin (Gorman et al., 2003), though the cytoprotective effect
that this activity may have in hypoxia has not been
investigated.
[0374] Despite the existence of these sophisticated defense
mechanisms against hypoxic damage, hypoxia is still often a
damaging stress. For example, mammals have both heme oxygenase-1
and HIF-1, and some evidence suggests that suspended animation is
possible in mammals as well (Bellamy et al., 1996; Alam et al.,
2002). Yet, hypoxic damage due to trauma such as heart attack,
stroke or blood loss is a major cause of death. The understanding
of the limitations of the two fundamental strategies for surviving
hypoxic stress, remaining animated or suspending animation, is
hampered by the fact that it has been based on studies in a variety
of systems under a variety of conditions.
[0375] "Hypoxia" occurs when the normal physiologic levels of
oxygen are not supplied to a cell or tissue. "Normoxia" refers to
normal physiologic levels of oxygen for the particular cell type,
cell state or tissue in question. "Anoxia" is the absence of
oxygen. "Hypoxic conditions" are those leading to cellular hypoxia.
These conditions depend on cell type, and on the specific
architecture or position of a cell within a tissue or organ, as
well as the metabolic status of the cell. For purposes of the
present invention, hypoxic conditions include conditions in which
oxygen concentration is at or less than normal atmospheric
conditions, that is less that 20.8, 20, 19, 18, 17, 16, 15, 14, 13,
12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, 0%; alternatively,
these numbers could represent the percent of atmosphere at 1
atmosphere of pressure (101.3 kPa). An oxygen concentration of zero
percent defines anoxic conditions. Thus, hypoxic conditions include
anoxic conditions, although in some embodiments, hypoxic conditions
of not less than 0.5% are implemented. As used herein, "normoxic
conditions" constitute oxygen concentrations of around 20.8% or
higher.
[0376] Standard methods of achieving hypoxia or anoxia are well
established and include using environmental chambers that rely on
chemical catalysts to remove oxygen from the chamber. Such chambers
are available commercially from, for example, BD Diagnostic Systems
(Sparks, Md.) as GASPAK Disposable Hydrogen+Carbon Dioxide
Envelopes or BIO-BAG Environmental Chambers. Alternatively, oxygen
may be depleted by exchanging the air in a chamber with a
non-oxygen gas, such as nitrogen. Oxygen concentration may be
determined, for example using a FYRITE Oxygen Analyzer (Bacharach,
Pittsburgh Pa.).
[0377] It is contemplated that methods of the invention can use a
combination of exposure to oxygen antagonist or other active
compound and alteration of oxygen concentrations compared to room
air. Moreover, the oxygen concentration of the environment
containing biological matter can be about, at least about, or at
most about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67,
68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84,
85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, or
100%, or any range derivable therein. Moreover, it is contemplated
that a change in concentration can be any of the above percentages
or ranges, in terms of a decrease or increase compared to room air
or to a controlled environment.
[0378] D. Mitochondrial Targeting Agents
[0379] Selectively targeting mitochondria is considered an
embodiment of the invention in some aspects so as to enhance
activity. Such selective mitochondrial targeting has been
accomplished by conjugating agents to a lipophilic
triphenylphosphonium cation, which readily cross lipid bilayers and
accumulate approximately a 1000 fold within the mitochondrial
matrix drive by the large potential (150 to -180 mv) across the
mitochondrial inner membrane. Analogs of both vitamin E and
ubiquinone have been prepared and used to successfully target
mitochondria. (Smith et al., 1999; Kelso et al., 2001; Dhanasekaran
et al., 2004). A thiol, thibutyltriphosphonium bromide (shown
below), has been prepared and used to target mitochondria wherein
it accumulated several hundred-fold (Burns et al., 1995; Burns
& Murphey), 1997).
##STR00004##
[0380] Such conjugates would appear to be suitable candidates for
active compounds. In addition to free thiol agents, thiosulfenyl
substituted compounds, (H--S--S--R) may be useful. It is
contemplated that in some embodiments the agents have the
structure:
##STR00005##
[0381] where Z is P or N;
[0382] R.sup.1, R.sup.2 and R.sup.3 are aryl, heteroaryl,
alkylaryl, cycloalkyl, or alkyl (suitably phenyl, benzyl, tolyl,
pyridyl, cyclohexyl, C.sub.3-C.sub.10 alkyl, optionally
halogenated);
[0383] R.sup.4 is --R.sup.5SR.sup.6, wherein R.sup.5 is
C.sub.1-C.sub.10 alkyl R.sup.6 is H or SO.sub.3H, or PO.sub.3H.
III. Testing for Stasis
[0384] Various compounds useful for inducing stasis may be
initially evaluated using a variety of different tests. Stasis can
be measured by a number of ways, including by quantifying the
amount of oxygen consumed by a biological sample, the amount of
carbon dioxide produced by the sample (indirect measurement of
cellular respiration), or characterizing motility.
[0385] To determine the rate of consumption of oxygen or the rate
of production of carbon dioxide the biological matter is placed
into a chamber that is sealed with two openings; for gas import and
export. Gas (room air or other gases) is passed into the chamber at
a given flow rate and out of the exit port to maintain
approximately 1 atmosphere of pressure in the chamber. Before and
after exposure to the chamber the gas is passed through a carbon
dioxide detector and or an oxygen detector to measure (every
second) the amount of each compound in the gas mixture. Comparison
of these values over time gives the rate of oxygen consumption or
carbon dioxide production.
[0386] Other screens to identify candidate active stasis compounds
have been established. These screens and variations of thereof may
be employed as part of the invention or to implement aspects of the
invention.
[0387] A. Assays with Zebrafish
[0388] A screening assay for stasis inducers was established using
48 hour old zebrafish (D. rerio) embryos. These embryos are
transparent, allowing one to view, using a dissecting microscope
with a 4-20 times power lense, the heart beat and resultant blood
flow into the main vessel along the back and into the tail. Heart
rate in these animals is an indicator of the metabolic activity of
the organism, such that a reduction in the heart rate signifies a
reduction in metabolism. Embryos were dissected from their egg
casings and distributed five per well in flat bottomed polystyrene
tissue culture plates and incubated in 1 mL of standard fish water.
The Dishwater is composed of 1 teaspoon Instant Ocean (artificial
sea water mixture, Aquarium Systems, Inc.) per 5 gallons. Calcium
chloride is adjusted to 150 ppm and sodium bicarbonate to 100 ppm.
Conductivity of the water is at 900 microsiemens and the pH is
about 6.5-7.4. A solution of hydrogen sulfide was prepared by
bubbling a mixture of hydrogen sulfide (100 ppm) balanced with room
air into a flask containing 150 mL of fishwater at a rate of 100
cubic centimeters per minute for 60-90 minutes. It was estimated
that this was sufficient to achieve a saturated or nearly saturated
or mostly saturated solution of hydrogen sulfide. Based on the
known solubility of hydrogen sulfide in Ringer's solution at pH 7
at 1 atmosphere and room temperature, it was estimated that the
fish water contained approximately 0.1 molar hydrogen sulfide. Fish
were exposed to the hydrogen sulfide solution and their heart rates
were monitored over the ensuing 24 hours by counting the number of
beats per minute. Control fish (exposed to fishwater alone) had
heart beats of approximately 160-200 beats per minute that did not
change significantly over the 24 hour observation period. By 2-3
hours following exposure to the hydrogen sulfide-containing
fishwater, heart beats were reduced by about half to 60-80 beats
per minute. By four hours, heart beats were reduced further,
including some examples where the heart beat was zero or only a few
beats per minute. After five hours of exposure, the hydrogen
sulfide solution was replaced with normal fishwater and the embryos
were allowed to recover overnight at 28 degrees Celsius. By 24
hours after initial exposure to hydrogen sulfide, treated and
rinsed animals displayed a normal heart rate of 160-200 beats per
minute. Because hydrogen sulfide caused the quiescence of the heart
beat, in some cases to a standstill, followed by a return to
normalcy, hydrogen sulfide was deemed to have been identified as a
stasis inducer or other active compound by the criteria of this
screening assay.
[0389] B. Assays with Nematodes
[0390] A screening assay was established using nematodes (C.
elegans). Nematodes do not survive well at 4 degrees Celsius, such
that at 24 hours at that temperature, they are all dead. Worms were
exposed for X minutes at room temperature to an atmosphere
containing Y % carbon monoxide, prior to exposing them to 4 degrees
C. for 16 hrs. Compared to control worms pre-exposed to room air
which were all dead, carbon monoxide treated worms survived with
high viability after exposure to cold. Since carbon monoxide is a
known stasis inducer in nematodes and neonatal human foreskin
keratinocytes, the nematode assay is capable of identifying stasis
inducing compounds as such by their ability to increase the
survivability of worms exposed to lethal hypothermia when the worms
are pre-equilibrated in the stasis inducer or other active
compound.
IV. Therapeutic or Preventative Applications
[0391] A. Trauma
[0392] In certain embodiments, the present invention may find use
in the treatment of patients who are undergoing, or who are
susceptible to trauma. Trauma may be caused by external insults,
such as burns, wounds, amputations, gunshot wounds, or surgical
trauma, internal insults, such as stroke or heart attack that
result in the acute reduction in circulation, or reductions in
circulation due to non-invasive stress, such as exposure to cold or
radiation. On a cellular level, trauma often results in exposure of
cells, tissues and/or organs to hypoxia, thereby resulting in
induction of programmed cell death, or "apoptosis." Systemically,
trauma leads to the induction of a series of biochemical processes,
such as clotting, inflammation, hypotension, and may give rise to
shock, which if it persists may lead to organ dysfunction,
irreversible cell damage and death. Biological processes are
designed to defend the body against traumatic insult; however they
may lead to a sequence of events that proves harmful and, in some
instances, fatal.
[0393] Therefore, the present invention contemplates the placement
of tissues, organs, limbs and even whole organisms into stasis as a
way of protecting them from the detrimental effects of trauma. In a
specific scenario, where medical attention is not readily
available, induction of stasis in vivo or ex vivo, alternatively in
conjunction with reduction in the temperature of the tissue, organ
or organism, can "buy time" for the subject, either by bringing
medical attention to the subject, or by transporting the subject to
the medical attention. The present invention also contemplates
methods for inducing tissue regeneration and wound healing by
prevention/delay of biological processes that may result in delayed
wound healing and tissue regeneration. In this context, in
scenarios in which there is a substantial wound to the limb or
organism, the induction of stasis induction of stasis in vivo or ex
vivo, alternatively in conjunction with reduction in the
temperature of the tissue, organ or organism, can aid in the wound
healing and tissue regeneration process by managing the biological
processes that inhibit healing and regeneration.
[0394] In addition to wound healing and hemorrhagic shock discussed
below, methods of the invention can be implemented to prevent or
treat trauma such as cardiac arrest or stroke. The invention has
particular importance with respect to the risk of trauma from
emergency surgical procedures, such as thoractomy, laparotomy, and
splenic transection.
[0395] 1. Wound Healing
[0396] In many instances, wounds and tissue damage are intractable
or take excessive periods of time to heal. Examples are chronic
open wounds (diabetic foot ulcers and stage 3 & 4 pressure
ulcers), acute and traumatic wounds, flaps and grafts, and subacute
wounds (i.e., dehisced incisions). This may also apply to other
tissue damage, for example burns and lung damage from smoke/hot air
inhalation.
[0397] Previous experiments show hibernation to be protective
against injury (e.g., pin's in brains), therefore it may have
healing effects. Consequently, this technology may be useful in the
control of wound healing processes, by bringing the tissue into a
more metabolically controlled environment. More particularly, the
length of time that cells or tissue are kept in stasis can vary
depending on the injury. In some embodiments of the invention,
biological matter is exposed to an oxygen antagonist or other
active compound for about, at least about, or at most about 30
seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55
minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2,
3, 4, 5 weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 months or
more.
[0398] 2. Hematologic Shock (Hemorrhagic Shock)
[0399] Shock is a life-threatening condition that progresses
rapidly when interventions are delayed. Shock is a state in which
adequate perfusion to sustain the physiologic needs of organ
tissues is not present. This is a condition of profound
haemodynamic and metabolic disturbance characterized by failure of
the circulatory system to maintain adequate perfusion of vital
organs. It may result from inadequate blood volume (hypovolaemic
shock), inadequate cardiac function (cardiogenic shock) or
inadequate vasomotor tone, also referred to as distributive shock
(neurogenic shock, septic shock, anaphylactic shock). This often
results in rapid mortality of the patient. Many conditions,
including sepsis, blood loss, impaired autoregulation, and loss of
autonomic tone, may produce shock or shocklike states. The present
invention is anticipated to prevent detrimental effects of all the
above states of shock, and sustain the life of the biological
matter undergoing such shock.
[0400] In hemorrhagic shock, blood loss exceeds the body's ability
to compensate and provide adequate tissue perfusion and
oxygenation. This is frequently due to trauma, but may also be
caused by spontaneous hemorrhage (e.g., gastrointestinal bleeding,
childbirth), surgery, and other causes. Most frequently, clinical
hemorrhagic shock is caused by an acute bleeding episode with a
discrete precipitating event. Less commonly, hemorrhagic shock may
be seen in chronic conditions with subacute blood loss.
[0401] Physiologic compensation mechanisms for hemorrhage include
initial peripheral and mesenteric vasoconstriction to shunt blood
to the central circulation. This is then augmented by a progressive
tachycardia. Invasive monitoring may reveal an increased cardiac
index, increased oxygen delivery (i.e., DO.sub.2), and increased
oxygen consumption (i.e., VO.sub.2) by tissues. Lactate levels, the
acid-base status, and other markers also may provide useful
indicators of physiologic status. Age, medications, and comorbid
factors all may affect a patient's response to hemorrhagic
shock.
[0402] Failure of compensatory mechanisms in hemorrhagic shock can
lead to death. Without intervention, a classic trimodal
distribution of deaths is seen in severe hemorrhagic shock. An
initial peak of mortality occurs within minutes of hemorrhage due
to immediate exsanguination. Another peak occurs after 1 to several
hours due to progressive decompensation. A third peak occurs days
to weeks later due to sepsis and organ failure.
[0403] In the United States, accidental injury is the leading cause
of morbidity and mortality in persons between the ages of 1 and 44
years. In 2001, 157,078 resident deaths occurred as the result of
injuries. Of these, 64.6 percent were classified as unintentional,
19.5 percent were suicides, 12.9 percent were homicides, 2.7
percent were of undetermined intent, and 0.3 percent involved legal
intervention or operations of war. The leading causes of injury
death were motor vehicle traffic, firearm, and falls. A large
proportion of these fatalities result from massive blood loss due
to the trauma, leading to hemorrhagic shock.
[0404] In the majority of trauma injury cases, patients who come to
a hospital's emergency department are treated by emergency
physicians and discharged without requiring surgery or care by a
trauma service. However, patients with serious injuries require
stabilization within the "Golden Hour" after the injury occurred,
to improve the chances of survival and to minimize disability.
[0405] As most shock cases are due to injury caused by an accident,
pre-hospital care is critical to the survival of the patient. This
involves rapid assessment, stabilization, and expeditious transport
to an appropriate center for evaluation and definitive care. In all
patients with shock syndrome, the maintenance of a patent airway,
adequate breathing and adequate circulation are the primary focus
of emergency treatment. Assessment is essential, as changes in
client condition indicate progression of the shock syndrome. Early
intervention is vital to minimize damage to tissues and organs and
minimize permanent disability and early identification of the
primary clinical cause is critical. Treatments are directed toward
correcting the cause of the shock syndrome and slowing progression.
Intravenous access and fluid resuscitation (typically IV saline)
are standard, however, there is some debate over this. Rapid
reversal of hypovolemia may increase hemorrhage, dislodge partially
formed clots, and dilute clotting factors.
[0406] Once at the emergency department, the focus is on optimizing
perfusion and oxygenation of vital organs. Diagnosis and management
of the underlying hemorrhage must be performed rapidly and
concurrently with management of shock. There are two major stages
of shock: early compensation stage and progressive stage. It is
contemplated that embodiments of the invention may be applied to
patients in either or both stages.
[0407] When hypovolemic shock results from massive hemorrage, the
replacement fluid of choice is whole blood or packed red blood
cells. Crystalloid solutions will temporarily improve circulating
volume, but the patient also needs replacement of red blood cells
to carry oxygen to the tissues. Management of shock focuses on
fluid management, acid-base balance, and improving myocardial
contraction. Treating the underlying cause of shock should also be
treated in order to diminish the progression of the shock syndrome.
Whole body hibernation was induced in mice, and there was an
immediate drop in overall metabolic state (as measured by CO.sub.2
evolution). This was reversible, and the mice seem to function
normally, even after repeated exposures. Accordingly, the invention
concerns inducing a whole body hibernetic state using H.sub.2S (or
other oxygen antagonist or other active compound), to preserve the
patient's vital organs and life. This will allow for transport to a
controlled environment (e.g., surgery), where the initial cause of
the shock can be addressed, and then the patient brought back to
normal function in a controlled manner. For this indication, the
first hour after injury, referred to as the "golden hour," is
crucial to a successful outcome. Stabilizing the patient in this
time period is the major goal, and transport to a critical care
facility (e.g., emergency room, surgery, etc.) where the injury can
be properly addressed. Thus, it would be ideal to maintain the
patient in stasis to allow for this and to address immediate
concerns such as source of shock, replenish blood loss, and
reestablish homeostasis. While this will vary significantly, in
most cases, the amount of time stasis will be maintained is between
about 6 and about 72 hours after injury. In some embodiments of the
invention, biological matter is exposed to an oxygen antagonist or
other active compound for about, at least about, or at most about
30 seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55
minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3, 4, 5, 6, 7 days or more,
and any range or combination therein.
[0408] The biology of lethal hemorrhage and the physiological
events that lead to shock and ultimately death are not fully
understood. However, there are mechanisms through which H.sub.2S
could reduce the lethal effects of ischemic hypoxia. Hydrogen
sulfide inhibits cytochrome C oxidase and could reduce oxygen
demand by inhibiting this enzyme.sup.3. Decreased oxygen demand may
reduce the deleterious effects of low oxygen levels including a
reduction of metabolic acidosis. Furthermore, tissue sulfydryl
levels decrease during shock (Beck et al., 1954). Exogenous
H.sub.2S may prevent this hyposulfidic state and maintain sulfur
homeostasis.
[0409] Hydrogen sulfide is naturally produced in animals and
exhibits potent biological activities (Kamoun, 2004). Most proteins
contain disulfide linked cysteine residues, and the reversible
conversion from free thiol to disulfide can regulate specific
enzyme activities (Ziegler, 1985). Furthermore, sulfide is
electronegative and exhibits high affinity for transition metals.
Proteins containing transition metal atoms, such as cytochrome
oxidase, can be profoundly affected by H.sub.2S. And finally,
metabolism of H.sub.2S into other molecules containing reduced
sulfur increases the number of thiols that may exhibit specific
biological activity. In addition to (or perhaps because of) these
potential modes of action, H.sub.2S may exert effects on
cardiopulmonary, neuroendocrine, immune, and/or hemostatic systems
that ultimately prove beneficial in injury and disease.
[0410] A U.S. provisional patent application entitled "Methods,
compositions and articles of manufacture for treating shock" filed
on Apr. 20, 2006 in the names of Mark B. Roth, Mike Morrison, and
Eric Blackstone describes the treatment of shock and is hereby
incorporated by reference.
[0411] B. Hypothermia
[0412] In yet another embodiment, the present inventor proposes use
of the present invention to treat people with extreme hypothermia.
The methods and compositions of the present invention are useful
for inducing hypothermia in a mammal in need of hypothermia.
Hypothermia can be mild, moderate or profound. Mild hypothermia
comprises achievement of a core body temperature of approximately
between 0.1 and 5 degrees Celsius below the normal core body
temperature of the mammal. The normal core body temperature of a
mammal is usually between 35 and 38 degrees Celsius. Moderate
hypothermia comprises achievement of a core body temperature of
approximately between 5 and 15 degrees Celsius below the normal
core body temperature of the mammal. Profound hypothermia comprises
achievement of a core body temperature of approximately between 15
and 37 degrees Celsius below the normal core body temperature of
the mammal.
[0413] Mild hypothermia is known in the art to be therapeutically
useful and effective in both non-human mammals and in humans. The
therapeutic benefit of mild hypothermia has been observed in human
clinical trials in the context of out-of-hospital cardiac arrest.
Exposure of humans to mild hypothermia in the context of cardiac
arrest results in a survival advantage and an improved neurological
outcome compared to standard of care with normothermia, or absence
of mild hypothermia (Bernard et al., 2002; The Hypothermia After
Cardiac Arrest Study Group et al. 2002).
[0414] Methods and compositions of the present invention may have
advantages over other methods known in the art, including, but not
limited to, packing the subject in ice, or surrounding the subject
with a "cooling tent" that circulates cool air or liquid, for
inducing mild, moderate, or profound hypothermia in mammals or
humans. In these cases, the subject resists the reduction of core
body temperature below normothermia and tries to generate heat by
shivering. Shivering, and the body heat engendered therein, can
have a negative impact on the achievement of mild hypothermia by,
for example, slowing the rate of decrease in the core body
temperature that is achieved using the standard methods of
hypothermia induction. Consequently, humans subjected to
therapeutic levels of hypothermia are also treated with a drug that
inhibits shivering (by blocking neurotransmission at the
neuromuscular junctions) (Bernard et al., 2002).
[0415] In a preferred embodiment, methods and compositions of the
present invention are combined with invasive methods or medical
devices known in the art to induce therapeutic hypothermia in
mammals or humans. Such invasive methods and devices include, but
are not limited to, flexible probes or catheters that can be
inserted into the vasculature of the subject in need of
hypothermia, wherein the temperature of the catheter is adjusted to
below the normal body temperature of the subject, resulting in the
cooling of blood which is in contact with the catheter. The cooled
blood subsequently engenders a decrease in the core body
temperature of the mammal. By incorporating feedback from a
thermocouple monitoring the core body temperature of the mammal,
the temperature of the catheter can be modulated so as to maintain
a pre-specified core body temperature. Such medical devices for
achieving and maintaining mild or moderate hypothermia, referred to
in the art as endovascular temperature therapy, are known in the
art and are described for example on the World Wide Web at
innercool.com and radiantmedical.com.
[0416] The method provides that patients with extreme hypothermia
are administered or exposed to an oxygen antagonist or other active
compound and then gradually restored to normal temperature while
withdrawing, in a controlled fashion, the oxygen antagonist or
other active compound. In this way, the oxygen antagonist or other
active compound buffers the biological systems within the subject
so that they may be initiated gradually without shock (or harm) to
the subject.
[0417] In one embodiment, a subject suffering from hypothermia with
be given an oral or intravenous dose of an oxygen antagonist or
other active compound. Intravenous provision may be preferred
because of the potential non-responsiveness of the subject and the
ability to provide a controlled dosage over a period of time.
Alternatively, if available, the oxygen antagonist or other active
compound may be provide in a gaseous state, for example, using a
mask for inhalation or even a sealed chamber that can house the
entire subject.
[0418] Ideally, the patient will be stabilized in terms of heart
rate, respiration and temperature prior to effecting any change.
Once stable, the ambient environmental temperature will be
increased, again gradually. This may be accomplished simply by
removing the subject from the hypothermic conditions. A more
regulated increase in temperature may be effected by adding
successive layers of clothing or blankets, by use of a thermal wrap
with gradual increase in heat, or if possible, by placing the
subject in chamber whose temperature may be gradually
increased.
[0419] It is preferred that the vital signs of the subject are
monitored over the course of the temperature increase. Also, in
conjunction with increasing the temperature, the oxygen antagonist
or other active compound is removed from the subject's environment.
Both heat and oxygen antagonist (or other active compound)
treatment are ceased at the appropriate endpoint, judged by the
medical personnel monitoring the situation, but in any event at the
time the subject's temperature and other vital signs return to a
normal range. Continued monitoring following cessation of treatment
is recommended for a period of at least 24 hrs.
[0420] C. Hyperthermia
[0421] Under certain conditions, which can result from genetic,
infectious, drug, or environmental causes, patients can loose
homeostatic temperature regulation resulting in severe
uncontrollable fever (hyperthermia). This can result in mortality
or long-term morbidity, especially brain damage, if it is not
controlled properly.
[0422] Mice inhaled H.sub.2S at 80 ppm immediately underwent
hibernation. This included an inability to regulate their body
temperature when ambient temperatures were dropped below room
temperature. Accordingly, this technology could be used to control
whole body temperature in certain states of hyperthermia. This
would likely involve administration of H.sub.2S (or other oxygen
antagonist or active compound) through inhalation or perfused into
the blood supply to induce a hibernation state. It would be useful
to have the patient to be in stasis for between about 6 and about
24 hours, during which time the source of the fever can be
addressed. In some embodiments of the invention, a patient is
exposed to an oxygen antagonist or other active compound for about,
at least about, or at most about 30 seconds, 1, 2, 3, 4, 5, 10, 15,
20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours,
1, 2, 3, 4, 5, 6, 7 days or more, and any range or combination
therein.
[0423] This can be combined with some whole-body temperature
regulation (ice bath/blanket/cooling system).
[0424] D. Cardioplegia and Coronary Heart Disease
[0425] In certain embodiments, the present invention may find use
as solutions for the treatment of coronary heart disease (CHD)
including a use for cardioplegia for cardiac bypass surgery
(CABG).
[0426] CHD results from athlerosclerosis, a narrowing and hardening
of the arteries that supply oxygen rich blood to the heart muscle.
The arteries harden and become narrow due to the buildup of plaque
on the inner walls or linings of the arteries. Blood flow to the
heart is reduced as plaque narrows the coronary arteries. This
decreases the oxygen supply to the heart muscle. This may manifest
in 1) angina, which is chest pain or discomfort that happens when
the heart is not getting enough blood; 2) heart attack, which can
occur when a blood clot suddenly cuts off most or all blood supply
to part of the heart and cells in the heart muscle that do not
receive enough oxygen-carrying blood begin to die, potentially
causing permanent damage to the heart muscle; 3) heart failure,
which is when the heart is unable to pump blood effectively to the
rest of the body; arrhythmias, which are changes in the normal
rhythm of the heartbeats.
[0427] Since 1990, more people have died from CHD than any other
cause. 3.8 million men and 3.4 million women die each year from
CHD. In 2002, over 500,000 people in the United States alone died
as a direct result of heart disease. Despite improvements in
survival rates, 1 in 4 men, and 1 in 3 women in the U.S. still die
within a year of a recognized first heart attack.
[0428] Medical treatment of CHD includes medications to reduce the
risk of heart attack, heart failure and stroke, together with
important lifestyle changes to prevent the further build-up of
fatty deposits in the coronary arteries. Nonetheless, some type of
surgical intervention is also frequently indicated.
[0429] About one-third of CHD patients will undergo coronary
angioplasty and stenting. During balloon angioplasty, a
balloon-tipped catheter is employed to push plaque back against the
arterial wall to allow for improved blood flow in the artery.
Coronary stenting often accompanies the angioplasty procedure.
Stents are small wire-mesh metal tubes that provide scaffolding to
support the damaged arterial wall, reducing the chance that the
vessel will close again (restenosis) after angioplasty. In the
United States, nearly one million balloon angioplasty procedures
are performed each year. Not all patients are able to be treated by
this technique; such patients must undergo heart surgery. Michaels
et al., 2002.
[0430] About 10% of CHD patients will undergo coronary artery
bypass graft (CABG) surgery. Patients with severe narrowing or
blockage of the left main coronary artery or those with disease
involving two or three coronary arteries are generally considered
candidates for bypass surgery. In CABG, the surgeon uses a portion
of a healthy vessel (either an artery or a vein) from another part
of the body to create a detour (or bypass) around the blocked
portion of the coronary artery. Patients typically receive from 1
to 5 bypasses in a given operation. During the procedure, generally
the heart is placed in a state of paralysis, known as cardioplegia
(CP), during which a heart-lung machine artificially maintains
circulation. Patients are under general anesthesia during the
operation, which usually lasts between 3 to 6 hours.
[0431] Approximately 13% of all patients will be re-admitted to the
hospital within 30 days due to reasons related to the CABG. Hannan
et al., 2003; Mehlhorn et al., 2001. One of the main reasons for
re-admission is heart failure, presumably due to ischemic damage
during the surgery. Thus, much work is being done to improve the
protection of the myocardium during the period when the heart is
not being perfused normally.
[0432] Recent advances in cardiac surgery have centered upon
optimization of cardioplegic parameters in the hope of preventing
postoperative ventricular dysfunction and improving overall
outcome. Cohen et al., 1999.
[0433] Cardioplegic solutions are perfused through the vessels and
chambers of the heart and cause its intrinsic beating to cease,
while maintaining the viability of the organ. Cardioplegia
(paralysis of the heart) is desirable during open-heart surgery and
during the procurement, transportation, and storage of donor hearts
for use in heart transplantation procedures.
[0434] Early cardioplegic techniques employed cold crystalloid
solutions to initiate and maintain intraoperative cardiac arrest.
However, it has become clear that blood cardioplegia facilitated
aerobic myocardial metabolism during the cross-clamp period and
reduced anaerobic lactate production. Furthermore, blood
cardioplegia improves oxygen carrying capacity, enhanced myocardial
oxygen consumption and preserved myocardial high-energy phosphate
stores. Several different cardioplegic solutions are available and
different techniques for using cardioplegia solutions are known in
the art. For example, cardioplegic solutions often have varying
amounts of potassium, magnesium, and several other minor
components. Sometimes drugs are added to the cardioplegic solution
to aid in muscle relaxation and protection from ischemia. Current
approaches also include blood-only formulations with appropriate
electrolyte supplementation, such as glutamate-aspartate. Specific
examples of frequently used solutions are the St Thomas Hospital
solution, University of Wisconsin Solution, Stanford Solution, and
the Bretschneider Solution. Examples of other emerging solutions
involve adenosine, insulin or L-arginine containing solutions
mentioned earlier. Varying the temperature at which the
cardioplegic solution is used may also have beneficial effects.
[0435] A combination of continuous retrograde along with
intermittent antegrade cardioplegia reduces myocardial lactate
production, preserved ATP stores, and improved metabolic recovery
after cross-clamp release. Tepid (29.degree. C.) cardioplegia
reduces lactate and acid production during cardioplegic arrest, and
improves post-operative ventricular function. Cardioplegic flows of
at least 200 mL/min are required to washout detrimental metabolic
end-products and improve ventricular function. It is abundantly
clear now that future directions in cardioplegic management will
involve the use of cardioplegic additives to further improve
protective effects. For example, attempts have been made to harness
the beneficial effects of ischemic pre-conditioning using
adenosine. Similarly, insulin cardiopolegia has been employed in
order to enhance ventricular performance by stimulating early
postoperative aerobic metabolism. Finally, L-arginine, a nitric
oxide donor has been demonstrated to be beneficial in experimental
studies and may represent a further option for the enhancement of
intraoperative myocardial protection. Future benefit of
cardioplegic supplementation is likely to be observed in high-risk
with poor ventricular function, for which current protective
techniques are inadequate. There is a steady increase in the
incidence of high-risk patients presenting, and these cases, and
consequent complications, place a disproportionate burden on the
health care system. Thus, improvements in this area hold great
promise for the advancement of care in this field.
[0436] Despite the protective effects provided by the current
methods for inducing cardioplegia, there is still some degree of
ischemic-reperfusion injury to the myocardium. Ischemic-reperfusion
injury during cardiac bypass surgery results in poor outcomes (both
morbidity and mortality), especially due to an already weakened
state of the heart. Myocardial ischemia results in anaerobic
myocardial metabolism. The end products of anaerobic metabolism
rapidly lead to acidosis, mitochondrial dysfunction, and myocyte
necrosis. High-energy phosphate depletion occurs almost
immediately, with a 50 percent loss of ATP stores within 10
minutes. Reduced contractility occurs within 1 to 2 minutes, with
development of ischemic contracture and irreversible injury after
30 to 40 minutes of normothermic (37.degree. C.) ischemia.
[0437] Reperfusion injury is a well-known phenomenon following
restoration of coronary circulation. Reperfusion injury is
characterized by abnormal myocardial oxidative metabolism. In
addition to structural changes created during ischemia, reperfusion
may produce cytotoxic oxygen free radicals. These oxygen free
radicals play a significant role in the pathogenesis of reperfusion
injury by oxidizing sarcolemmal phospholipids and thus disrupting
membrane integrity. Oxidized free fatty acids are released into the
coronary venous blood and are a marker of myocardial membrane
phospholipid peroxidation. Protamine induces complement activation,
which activates neutrophils. Activated neutrophils and other
leukocytes are an additional source of oxygen free radicals and
other cytotoxic substances.
[0438] The present invention provides methods and compositions for
inducing cardioplegia that will provide greater protection to the
heart during bypass surgery. In certain embodiments, the present
invention provides a cardioplegic solution comprising H.sub.2S (or
another active compound) dissolved in solution or bubbled as a gas
in the solution. In some embodiments, the invention further
comprises at least a first device, such as a catheter or cannula,
for introducing an appropriate dose of the cardioplegic solution to
the heart. In certain aspects, the invention further comprises at
least a second device, such as a catheter or cannula, for removing
the cardioplegic solution from the heart.
[0439] Bypass surgery typically last for 3-6 hours, however,
complications and multiple vessel CABG can extend the duration to
12 hours or longer. It is contemplated that the heart would be kept
in stasis during the surgery. Thus, in some embodiments of the
invention, the heart is exposed to an oxygen antagonist or other
active compound for about, at least about, or at most about 30
seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55
minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18 hours or more, and any range or combination therein.
[0440] E. Reducing Damage from Cancer Therapy
[0441] Cancer is a leading cause of mortality in industrialized
countries around the world. The most conventional approach to the
treatment of cancer is by administering a cytotoxic agent to the
cancer patient (or treatment ex vivo of a tissue) such that the
agent has a more lethal effect on the cancer cells than normal
cells. The higher the dose or the more lethal the agent, the more
effective it will be; however, by the same token, such agents are
all that more toxic (and sometimes lethal) to normal cells. Hence,
chemo- and radiotherapy are often characterized by severe side
effects, some of which are life threatening, e.g., sores in the
mouth, difficulty swallowing, dry mouth, nausea, diarrhea,
vomiting, fatigue, bleeding, hair loss and infection, skin
irritation and loss of energy (Curran, 1998; Brizel, 1998).
[0442] Recent studies suggest that transient and reversible
lowering of the core body temperature, or "hypothermia," may lead
to improvements in the fight against cancer. Hypothermia of
28.degree. C. was recently found to reduce radiation,
doxorubicin-and cisplatin-induced toxicity in mice. The cancer
fighting activity of these drugs/treatments was not compromised
when administered to cooled animals; rather, it was enhanced,
particularly for cisplatin (Lundgren-Eriksson et al., 2001). Based
on this and other published work, the inventor proposes a further
reduction in core temperature will provide benefit to cancer
patients. Thus, the present invention contemplates the use of
oxygen antagonists or other active stasis compound to induce stasis
in normal tissues of a cancer patient, thereby reducing the
potential impact of chemo- or radiotherapy on those tissues. It
also permits the use of higher doses of chemo- and radiotherapy,
thereby increasing the anti-cancer effects of these treatments.
[0443] Treatment of virtually any hyperproliferative disorder,
including benign and malignant neoplasias, non-neoplastic
hyperproliferative conditions, pre-neoplastic conditions, and
precancerous lesions, is contemplated. Such disorders include
restenosis, cancer, multi-drug resistant cancer, primary psoriasis
and metastatic tumors, angiogenesis, rheumatoid arthritis,
inflammatory bowel disease, psoriasis, eczema, and secondary
cataracts, as well as oral hairy leukoplasia, bronchial dysplasia,
carcinomas in situ, and intraepithelial hyperplasia. In particular,
the present invention is directed at the treatment of human cancers
including cancers of the prostate, lung, brain, skin, liver,
breast, lymphoid system, stomach, testicles, ovaries, pancreas,
bone, bone marrow, gastrointestine, head and neck, cervix,
esophagus, eye, gall bladder, kidney, adrenal glands, heart, colon
and blood. Cancers involving epithelial and endothelial cells are
also contemplated for treatment.
[0444] Generally, chemo- and radiotherapy are designed to reduce
tumor size, reduce tumor cell growth, induce apoptosis in tumor
cells, reduce tumor vasculature, reduce or prevent metastasis,
reduce tumor growth rate, accelerate tumor cell death, and kill
tumor cells. The goals of the present invention are no different.
Thus, it is contemplated that one will combine oxygen antagonist
(or other active compound) compositions of the present invention
with secondary anti-cancer agents (secondary agents) effective in
the treatment of hyperproliferative disease. An "anti-cancer" agent
is capable of negatively affecting cancer in a subject, for
example, by killing cancer cells, inducing apoptosis in cancer
cells, reducing the growth rate of cancer cells, reducing the
incidence or number of metastases, reducing tumor size, inhibiting
tumor growth, reducing the blood supply to a tumor or cancer cells,
promoting an immune response against cancer cells or a tumor,
preventing or inhibiting the progression of cancer, or increasing
the lifespan of a subject with cancer.
[0445] Secondary anti-cancer agents include biological agents
(biotherapy), chemotherapy agents, and radiotherapy agents. More
generally, these other compositions are provided in a combined
amount effective to kill or inhibit proliferation of the cancer or
tumor cells, while at the same time reducing or minimizing the
impact of the secondary agents on normal cells. This process may
involve contacting or exposing the cells with an oxygen antagonist
(or other active compound) and the secondary agent(s) at the same
time. This may be achieved by contacting the cell with a single
composition or pharmacological formulation that includes both
agents, or by contacting or exposing the cell with two distinct
compositions or formulations, at the same time, wherein one
composition includes an oxygen antagonist and the other includes
the second agent(s).
[0446] Alternatively, the oxygen antagonist (or other active
compound) therapy may precede or follow the secondary agent
treatment by intervals ranging from minutes to weeks. In
embodiments where the other agent and expression construct are
applied separately to the cell, one would generally ensure that a
significant period of time did not expire between the time of each
delivery, such that the agent and expression construct would still
be able to exert an advantageously combined effect on the cell. In
such instances, it is contemplated that one may contact the cell
with both modalities within about 12-24 h of each other and, more
preferably, within about 6-12 h of each other. In some situations,
it may be desirable to extend the time period for treatment
significantly, however, where several days (2, 3, 4, 5, 6 or 7) to
several weeks (1, 2, 3, 4, 5, 6, 7 or 8) lapse between the
respective administrations. In certain embodiments, it is
envisioned that biological matter will be kept in stasis for
between about 2 and about 4 hours while the cancer treatment is
being administered. In some embodiments of the invention,
biological matter is exposed to an oxygen antagonist or other
active compound for about, at least about, or at most about 30
seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55
minutes, 1, 2, 3, 4, 5, 6 hours or more, and any range or
combination therein.
[0447] Various combinations may be employed; the active compound is
"A" and the secondary anti-cancer agent, such as radio- or
chemotherapy, is "B":
TABLE-US-00001 A/B/A B/A/B B/B/A A/A/B A/B/B B/A/A A/B/B/B B/A/B/B
B/B/B/A B/B/A/B A/A/B/B A/B/A/B A/B/B/A B/B/A/A B/A/B/A B/A/A/B
A/A/A/B B/A/A/A A/B/A/A A/A/B/A
[0448] Administration of the oxygen antagonists or other active
compounds of the present invention to a patient will follow general
protocols for the administration of chemotherapeutics, taking into
account the toxicity, if any, of the compound. It is expected that
the treatment cycles would be repeated as necessary. It also is
contemplated that various standard therapies, as well as surgical
intervention, may be applied in combination with the
above-described anti-cancer therapy. It is further contemplated
that any combination treatment contemplated for use with an active
compound and a non-active compound (such as chemotherapy), may be
applied with respect to multiple active compounds.
[0449] 1. Chemotherapy
[0450] Cancer therapies also include a variety of combination
therapies with both chemical and radiation based treatments.
Combination chemotherapies include, for example, cisplatin (CDDP),
carboplatin, procarbazine, mechlorethamine, cyclophosphamide,
camptothecin, ifosfamide, melphalan, chlorambucil, busulfan,
nitrosurea, dactinomycin, daunorubicin, doxorubicin, bleomycin,
plicomycin, mitomycin, etoposide (VP16), tamoxifen, raloxifene,
estrogen receptor binding agents, taxol, gemcitabien, navelbine,
farnesyl-protein transferase inhibitors, transplatinum,
5-fluorouracil, vincristine, vinblastine and methotrexate,
Temazolomide (an aqueous form of DTIC), or any analog or derivative
variant of the foregoing. The combination of chemotherapy with
biological therapy is known as biochemotherapy.
[0451] 2. Radiotherapy
[0452] Other factors that cause DNA damage and have been used
extensively include what are commonly known as trays, X-rays,
and/or the directed delivery of radioisotopes to tumor cells. Other
forms of DNA damaging factors are also contemplated such as
microwaves and UV-irradiation. It is most likely that all of these
factors effect a broad range of damage on DNA, on the precursors of
DNA, on the replication and repair of DNA, and on the assembly and
maintenance of chromosomes. Dosage ranges for X-rays range from
daily doses of 50 to 200 roentgens for prolonged periods of time (3
to 4 wk), to single doses of 2000 to 6000 roentgens. Dosage ranges
for radioisotopes vary widely, and depend on the half-life of the
isotope, the strength and type of radiation emitted, and the uptake
by the neoplastic cells.
[0453] The terms "contacted" and "exposed," when applied to a cell,
are used herein to describe the process by which a composition of
the invention (for example, a hypoxic antitumor compound) or a
chemotherapeutic or radiotherapeutic agent is delivered to a target
cell or are placed in direct juxtaposition with the target cell. In
combination therapy, to achieve cell killing or stasis, both agents
may be delivered to a cell in a combined amount effective to kill
the cell or prevent it from dividing.
[0454] 3. Immunotherapy
[0455] Immunotherapeutics, generally, rely on the use of immune
effector cells and molecules to target and destroy cancer cells.
The immune effector may be, for example, an antibody specific for
some marker on the surface of a tumor cell. The antibody alone may
serve as an effector of therapy or it may recruit other cells to
actually effect cell killing. The antibody also may be conjugated
to a drug or toxin (chemotherapeutic, radionuclide, ricin A chain,
cholera toxin, pertussis toxin, etc.) and serve merely as a
targeting agent. Alternatively, the effector may be a lymphocyte
carrying a surface molecule that interacts, either directly or
indirectly, with a tumor cell target. Various effector cells
include cytotoxic T cells and NK cells.
[0456] Immunotherapy could also be used as part of a combined
therapy. The general approach for combined therapy is discussed
below. In one aspect of immunotherapy, the tumor cell must bear
some marker that is amenable to targeting, i.e., is not present on
the majority of other cells. Many tumor markers exist and any of
these may be suitable for targeting in the context of the present
invention. Common tumor markers include carcinoembryonic antigen,
prostate specific antigen, urinary tumor associated antigen, fetal
antigen, tyrosinase (p97), gp68, TAG-72, HMFG, Sialyl Lewis
Antigen, MucA, MucB, PLAP, estrogen receptor, laminin receptor, erb
B and p155. An alternative aspect of immunotherapy is to anticancer
effects with immune stimulatory effects. Immune stimulating
molecules also exist including: cytokines such as IL-2, IL-4,
IL-12, GM-CSF, gamma-IFN, chemokines such as MIP-1, MCP-1, IL-8 and
growth factors such as FLT3 ligand. Combining immune stimulating
molecules, either as proteins or using gene delivery in combination
with a tumor suppressor such as mda-7 has been shown to enhance
anti-tumor effects (Ju et al., 2000)
[0457] As discussed earlier, examples of immunotherapies currently
under investigation or in use are immune adjuvants (e.g.,
Mycobacterium bovis, Plasmodium falciparum, dinitrochlorobenzene
and aromatic compounds) (U.S. Pat. No. 5,801,005; U.S. Pat. No.
5,739,169; Hui and Hashimoto, 1998; Christodoulides et al., 1998),
cytokine therapy (e.g., interferons .alpha., .beta. and .gamma.;
IL-1, GM-CSF and TNF) (Bukowski et al., 1998; Davidson et al.,
1998; Hellstrand et al., 1998) gene therapy (e.g., TNF, IL-1, IL-2,
p53) (Qin et al., 1998; Austin-Ward and Villaseca, 1998; U.S. Pat.
No. 5,830,880 and U.S. Pat. No. 5,846,945) and monoclonal
antibodies (e.g., anti-ganglioside GM2, anti-HER-2, anti-p185)
(Pietras et al., 1998; Hanibuchi et al., 1998). Herceptin
(trastuzumab) is a chimeric (mouse-human) monoclonal antibody that
blocks the HER2-neu receptor. It possesses anti-tumor activity and
has been approved for use in the treatment of malignant tumors
(Dillman, 1999). Combination therapy of cancer with herceptin and
chemotherapy has been shown to be more effective than the
individual therapies. Thus, it is contemplated that one or more
anti-cancer therapies may be employed with the anti-tumor therapies
described herein.
[0458] F. Neurodegeneration
[0459] The present invention may be used to treat neurodegenerative
diseases. Neurodegenerative diseases are characterized by
degeneration of neuronal tissue, and are often accompanied by loss
of memory, loss of motor function, and dementia. With dementing
diseases, intellectual and higher integrative cognitive faculties
become more and more impaired over time. It is estimated that
approximately 15% of people 65 years or older are mildly to
moderately demented. Neurodegenerative diseases include Parkinson's
disease; primary neurodegenerative disease; Huntington's Chorea;
stroke and other hypoxic or ischemic processes; neurotrauma;
metabolically induced neurological damage; sequelae from cerebral
seizures; hemorrhagic shock; secondary neurodegenerative disease
(metabolic or toxic); Alzheimer's disease, other memory disorders;
or vascular dementia, multi-infarct dementia, Lewy body dementia,
or neurodegenerative dementia.
[0460] Evidence shows that the health of an organism, and
especially the nervous system, is dependent upon cycling between
oxidative and reductive states, which are intimately linked to
circadian rhythms. That is, oxidative stress placed upon the body
during consciousness is cycled to a reductive environment during
sleep. This is thought to be a large part of why sleep is so
important to health. Certain neurodegenerative disease states, such
as Huntington's disease and Alzheimer's disease, as well as the
normal processes of aging have been linked to a discord in this
cycling pattern. There is also some evidence that brain H.sub.2S
levels are reduced in these conditions (Eto et al., 2002).
[0461] The present invention can be used to regulate and control
the cycling between the oxidative and reduced states, for example,
to prevent or reverse the effects of neurodegenerative diseases and
processes. Controlling circadian rhythms can have other
applications, for example, to adjust these cycling patterns after
traveling from one time zone to another, so as to adjust to the new
time zone. Furthermore, reduced metabolic activity overall has been
shown to correlate with health in aged animals and humans.
Therefore, the present invention would also be useful to suppress
overall metabolic function to increase longevity and health in old
age. It is contemplated that this type of treatment would likely be
administered at night, during sleep for period of approximately 6
to 10 hours each day. This could require daily treatment for
extended periods of time from months to years.
[0462] G. Aging
[0463] Furthermore, in certain states of stasis, including but not
limited to states where the biological matter is in a state of
suspended animation, aging itself may be thoroughly or completely
inhibited for the period of time when the biological matter is in
that state. Thus the present invention may inhibit aging of
biological material, with respect to extending the amount of time
the biological material would normally survive and/or with respect
to progression from one developmental stage of life to another.
[0464] H. Blood Disease
[0465] A number of blood diseases and conditions may be addressed
using compositions and methods of the invention. These diseases
include, but are not limited to, thalassemia and sickle cell
anemia.
[0466] 1. Thalassemia
[0467] Normal hemoglobin contains two alpha and two beta globin
polypeptide (protein) chains, each bound to an iron containing heme
ring. Thalassemia is a group of conditions in which there is an
imbalance of alpha and beta chains leading to the unpaired chains
precipitating on the normally fragile red blood cell membrane,
leading to cell destruction. This leads to severe anemia that the
marrow tries to compensate for by trying to make more red cells.
Unfortunately due to toxicity from unpaired chains this process is
very inefficient leading to massive expansion of the marrow space
and spread of blood making to other parts of the body. This and the
anemia lead to major toxicities. Several models exist as to why
unpaired globin chains are so damaging but many entail that
increased free radicals generated by the iron attached to the
unpaired globin chains are central to the early destruction of the
red cells. Thus any intervention that might decrease the oxidative
damage from these free radicals could increase red cell lifespan,
improve the anemia, lead to decreased need for making red cells,
and less damage from marrow expansion and spread.
[0468] It is estimated that over 30,000 children are born with
severe thalassemia each year, of which it is estimated that most
living in developed countries live into their twenties, while in
third world countries (where the majority of patients live) most
die as young children. Based on the current results in other model
systems presented here, it expected that exposing animals with
thalassemia to sulfides will increase their red cells' ability to
withstand oxidative damage, leading to prolonged red cell
survival.
[0469] 2. Sickle Cell Disease
[0470] Normal hemoglobin (HbA) contains two alpha and two beta
globin polypeptide (protein) chains, each bound to an iron
containing heme ring. In sickle cell disease (SCD; also called
sickle cell anemia) is a group of conditions in which a mutant beta
chain leads to an altered hemoglobin (HbS). Upon deoxygention HbS
can polymerize (crystallize) and precipitate damaging the normally
fragile red blood cell membrane, leading to cell destruction and
anemia low red blood cells (RBC). In addition cells with
polymerized HbS change shape (sickle) and become sticky and
activate mechanisms leading to coagulation and blockage of blood
flow. This can lead to hypoxic damage of the surrounding tissue
resulting in pain, organ dysfunction and eventually premature
death. Decreased stores of sulfur containing antioxidants are noted
in patients. In addition oxidative damage and increased reactive
oxygen species (ROS) have been implicated in crystallization, RBC
membrane damage and tissue damage related to inadequate blood flow.
Sulfides have been implicated in "re-charging" antioxidant stores,
and potentially minimizing oxidative damage. There are reasons to
think sulfides could prevent problems at several stages of sickle
cell pathology. Furthermore, given the ability of oxygen
antagonists to protect from hypoxia in other systems, suggests that
it should also protect animals and humans subjected to the adverse
conditions posed by this disease state.
[0471] Over 120,000 children are born with SCD each year. Patients
in developed countries now live into their 40's and 50's however
with tremendous problems with pain and organ damage including
stroke, lung, heart and skin problems. In third world countries
(where the majority of patients live) most die as young children.
Our hypothesis is that exposing animals and eventually humans with
SCD to sulfides will result in health improvements.
IV. Preservation Applications
[0472] The present invention can be used to preserve or store a
variety of biological matter, including cells, tissues, organs, and
whole organisms for transport and/or storage purposes. In certain
embodiments, the biological matter is preserved so as to prevent
damage from adverse conditions.
[0473] In embodiments of the invention, biological matter can be
exposed to an active compound for about, at least about, or at most
about 30 seconds, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45,
50, 55 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23, 24 hours, 1, 2, 3, 4, 5, 6, 7 days,
1, 2, 3, 4, 5 weeks, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 months,
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
20 or more years, and any combination or range derivable therein.
It is contemplated that active compounds may be used to induce
stasis and that other agents may be used to maintain stasis and
preserve them for any significant period of time. Alternatively, it
is contemplated that an active compound may be used to induce
and/or maintain stasis. This may be in combination with other
agents, such environmental changes in pressure and/or
temperature.
[0474] 1. Cells
[0475] As discussed above, a variety of cells are contemplated for
use with the present invention. It is contemplated that such cells
can be preserved in methods, apparatuses, and compositions of the
invention.
[0476] a. Platelets
[0477] In certain embodiments, the present invention may find use
in the preservation of platelets. Platelets are small cell
fragments (.about.1/3 size of erythrocytes) that play a vital role
in the formation of blood clots at the site of bleeding. Hemostasis
is achieved by adherence to the walls of blood vessels, release of
coagulating chemicals, forming blood clots to plug the rupture in
the vascular wall and/or narrowed blood vessels. Normal platelet
counts are between 150,000-400,000 counts/.mu.L. Platelet
concentrates are transfused for a variety of indications, for
example: 1) to prevent bleeding due to thrombocytopenia; 2) in a
bleeding patient to maintain a platelet count above 50,000; 3) to
address abnormal platelet function that is congenital or due to
medications, sepsis, malignancy, tissue trauma, obstetrical
complications, extra corporeal circulation, or organ failure such
as liver or kidney disease.
[0478] Each unit of platelets contains an average of
0.8-0.85.times.10.sup.11 platelets. Platelet concentrates also
contain about 60 mL of plasma (coagulation factors) and small
numbers of red blood cells and leukocytes. Platelet units must be
maintained at room temperature (20.degree. C.-24.degree. C.) and
agitated during storage. They can be stored at the Blood Center for
up to 5 days. Longer storage is not possible at present due to
deterioration of the platelets, and the risk of microbial
contamination. Two sources of platelets currently exist:
[0479] 1) Pooled random donor platelet concentrates are prepared
from platelets that have been harvested by centrifuging units of
whole blood. Up to 8 units of platelets, each from a separate
donor, can be pooled into a single bag for transfusion. Platelets
expire 4 hours after pooling. All units are from the same ABO type.
If ABO compatible platelets are unavailable, ABO incompatible
platelets can be substituted with very little risk. The usual adult
dose is 4-6 units of pooled random donor platelets.
[0480] 2) Apheresis platelets, collected from a single donor, are
prepared in standard (equivalent to .about.4 pooled units) and
"large" (equivalent to .about.6 pooled units) sizes. An apheresis
platelet concentrate contains 200-400 mL of plasma. They may be
collected as a random unit (random apheresis platelets) or be
obtained for a specific recipient from a family member or a
volunteer HLA compatible "directed" donor. Apheresis platelets
expire 4 hours after processing for release from the blood
center.
[0481] Platelet storage poses problems that are not found with the
storage of whole blood or other components. While whole blood, red
and white cells may be stored at 4.degree. C. for weeks, platelets
will aggregate in cold storage and when allowed to settle.
Therefore, the standard method of storing platelets is at room
temperature, approximately 20 to 24.degree. C., with gentle
agitation. Even under these conditions, platelets can only be
stored for 5 days before they need to be discarded. This problem of
outdating results in approximately $500 million annually in lost
revenue for US hospitals. If even a moderate increase in shelf life
could be attained, approximately 90% of this loss could be
avoided.
[0482] An additional problem with platelet storage is bacterial
contamination. Contamination is primarily due to staphylococci from
the skin during the phlebotomy, or else donor bacteremia. The
bacterial contamination of platelets represents the largest
infectious risk with any blood transfusion procedure.
[0483] A significant factor affecting the viability of platelets is
regulation of pH. Virtually all units of platelets stored according
to the currently accepted methods show a decrease in pH from their
initial value of approximately 7.0. This decrease is primarily due
to the production of lactic acid by platelet glycolysis and to a
lesser extent to accumulation of CO.sub.2 from oxidative
phosphorylation. As the pH falls, the platelets change shape from
discs to spheres. If the pH falls below 6.0, irreversible changes
in platelet morphology and physiology render them non-viable after
transfusion. An important goal in platelet preservation, therefore,
is to prevent this decrease in pH. It was previously thought that
platelets must be stored in a container permeable to oxygen since
glycolysis is stimulated when oxygen availability is limited (see
e.g., U.S. Pat. No. 5,569,579). The present invention, however,
demonstrates that the viability of stored platelets can be extended
by storing them in an anoxic environment.
[0484] The present invention provides methods and compositions that
increase the survival time of stored platelets and reduce bacterial
contamination. In one embodiment, the present invention provides a
sealable, oxygen-impermeable container into which the platelets are
placed. After sealing, an anaerobic generator (e.g., a sodium
borohydride tablet with a palladium catalyst) converts the
atmospheric oxygen in the container to water. The container can
also contain an indicator, which indicates the level of oxygen
tension. Once in anoxic conditions, the platelets can also be
stored at lower temperatures.
[0485] The platelets may be suspended and stored in plasma or any
platelet storage solution known in the art. For example, U.S. Pat.
Nos. 4,828,976 and 4,447,415 disclose several commonly used
solutions suitable for the storage of platelets.
[0486] Typically, platelets are stored in plasma from the donor and
administered in that form.
[0487] Generally, the invention consists of a sealed environment
(container, jar, impermeable bag, or chamber) in which the oxygen
tension can be reduced to less than 1% (10,000 ppm) and more
specifically in the range of 10-100 ppm, or less. The reduction in
atmospheric oxygen in this environment can be achieved by a number
of methods known in the art. For example, the reduction in
atmospheric oxygen can be achieved with the generation of hydrogen
gas, with or without a catalyst, to combine with the oxygen to
produce water. Other reactions could be catalyzed to combine the
oxygen with other compounds, such as carbon to produce carbon
dioxide, and so on. Also, the oxygen could be replaced by
exchanging all the air in the chamber with gas containing any
combination of gases that do not include oxygen. Also, the oxygen
could be removed by placing the chamber under vacuum, to remove all
gases. Alternatively, the oxygen could be competed by using another
gas or compound that competes for oxygen, such as CO. A combination
of removal of oxygen and competition of remaining oxygen could also
be used. The device may also comprise a way to measure the
concentration of oxygen to ensure the appropriate anaerobic state
has been achieved. For example, oxygen concentration can be
measured using an anaerobic indicator based on methlyene blue that
changes from blue color to colorless in the absence of oxygen.
Alternatively, an oxygen meter or other oxygen measuring device
could be used.
[0488] The device also comprises some way to contain the platelets
in the sealed environment such that the oxygen can be removed from
the solution containing the platelets, as well as from the
platelets themselves. An example of this is to have the platelets
in a gas-permeable bag placed inside the sealed environment. The
platelets could also be held in an open container inside the sealed
environment. Alternatively, the platelets could be placed directly
in the impermeable, sealed container/bag.
[0489] The Bio-Bag.TM. from Becton Dickinson (product number
261215) is one example of a sealable, oxygen-impermeable container
that can be used to create an anoxic environment for the storage of
platelets. The Bio-Bag, which is a kit sold for the isolation of
anaerobic bacteria, includes a sealable, gas-impermeable bag; an
anaerobic indicator; an anaerobic generator (hydrogen gas
generator); and palladium catalysts. The platelets in a
gas-permeable bag, would be sealed inside of the Bio-Bag for
storage.
[0490] The anaerobic generator in the Bio-Bag is a device activated
by the addition of water, which passes through a series of channels
to a filter paper wick. The wick delays and regulates the
introduction of water into the tablet chamber, providing a
controlled release of the hydrogen gas. The gas-generating tablet
consists of sodium borohydride. The hydrogen released from this
reaction, combines with the atmospheric oxygen in the sealed
container to produce water. This reaction is catalyzed by the
palladium in the container.
[0491] The Puget Sound Blood Center (PSBC) independently assessed
the state of the platelets stored in anoxic conditions on days 0, 5
and 8 using a standardized panel of in vitro tests. Results
indicated that platelets stored in anoxic conditions for up to 8
days perform as good, or better than, platelets stored under
standard conditions. Ongoing studies are replicating this
experiment, and extending the observation time to 13 days.
[0492] Those of skill in the art will be familiar with methods for
assaying platelet function. For example, as described in U.S. Pat.
No. 6,790,603, platelet function can be assayed by (1) internal
protein expression on the cell membrane in response to challenge
with an activation-inducing agonist; (2) ability to aggregate when
challenged by an agonist; and (3) adenosine triphosphate secretion.
Examples of agonist that can cause activation of platelet function
include thrombin, epinephrine, ADP and collagen.
[0493] Internal protein expression may be measured by conjugation
of a molecule with a fluorescent dye, followed by sorting in a
fluorescent cell sorter. In general, it is preferable to use two
monoclonal antibodies, one that binds a cell surface molecule that
is constitutively expressed and a second that binds a cell surface
molecule that is expressed only after activation. Each monoclonal
antibody is conjugated to a different colored dye, that can be
distinguished by spectrofluorometry. A non-limiting example of a
constitutively expressed cell surface molecule is GPIIbIIIa; a
non-limiting example of a cell surface molecule expressed after
activation is P-selectin. It is well know in the art to make
monoclonal antibodies to proteins. U.S. Pat. No. 5,470,738, is one
example of a method of making monoclonal antibodies to GPIIIa.
Another anti-platelet monoclonal antibody is that to GP IV, as
disclosed by U.S. Pat. No. 5,231,025. Antibodies can also be
purchased commercially from such companies as Becton-Dickinson
(Philadelphia).
[0494] Another parameter of platelet function is the ability to
aggregate when challenged by an agonist. The platelet suspension is
dense and milky white. Aggregation and subsequent settling of the
aggregates can be estimated visually, or measured with a
densitometer.
[0495] Yet another measure of platelet function is the secretion of
ATP. Platelets that are able to function well are able to secrete
ATP while cells that have already been activated or have lost
function in other ways cannot secrete ATP.
[0496] 2. Cell Culture
[0497] The present invention can be extended to protecting cells in
culture, which might otherwise die or be induced into apoptosis. In
the context of the present invention, cells are exposed to an
active compound prior to and/or while in culture. Cells that can be
cultured according to the invention include those that can
eventually be placed back into a physiological context, i.e., those
for subsequent transplant. Such cells include, but are not limited
to, bone marrow, skin cells and epithelial cells. Also, some
transplantable cells would greatly benefit from expansion in
culture, thereby increasing the amount of material that can be
introduced into the host. Epithelial cells from the
gastrointestinal tract are specifically contemplated as cells that
can benefit from exposure to an active compound.
[0498] Furthermore, the invention extends to the culture of tumor
cells. Culture of tumor cells is known to result in alteration of
the phenotype, and in some cases death. This makes tissue culture
experiments on tumor cells highly unpredictable.
[0499] General cell culture techniques are well known to those of
skill in the art. Examples of this knowledge can be found in Shaw
(1996) and Davis (1994), both of which are incorporated by
reference herein. General information and modifications of
traditional cell culture techniques is also found in U.S. Pat. No.
5,580,781, which is incorporated by reference. Furthermore,
techniques for culturing skin cells are described in U.S. Pat. No.
6,057,148, which is incorporated by reference. It is contemplated
that these techniques, as well as others known to those of skill in
the art, will be supplemented with media containing one or more
active compounds, or perfused with an active compound as liquids
and/or gases.
[0500] E. Preservation of Cells, Tissue and Organs
[0501] In certain embodiments of the invention, it is desirable to
preserve biological matter, so as to prevent as much as possible
damage to the matter from perishing or decomposing. Though the
first successful kidney transplant was performed in 1954 and the
first heart and liver transplants were conducted in 1967, every
year, thousands of people die in need of an organ transplant. Due
to a variety of causes, they need hearts, lungs, kidneys, and
livers. In addition, there are patients who could use a pancreas or
a cornea. While there is a constant need for organ donors, another
significant hurdle in providing those in need of an organ
transplant with an organ is the limitations in current organ
preservation techniques. For example, it is widely believed that a
human heart must be transported within four hours for there to be
any chance of the subsequent transplantation to be a success.
Rager, 2004 (see table below).
TABLE-US-00002 Maximum cold ischemic time Organ Preservation Time
Heart and Lungs 4-6 hours Liver 12-24 hours Kidney 48-72 hours
Pancreas 12-24 hours Small Intestine 12 hours
Moreover, the primary cause of organ transplant failure for
transplanted hearts in the first 30 days is ischemic-reperfusion
injury.
[0502] Organ procurement and preservation, tissue matching, and
immunosuppression are the principal ingredients for successful
solid organ transplantation. The technical aspects of the organ
procurement operation allow multiple teams to work together to
procure all useful organs form a single donor. On average, 3.6
organs are procured from a single deceased donor.
[0503] Preserving solid organs depends on rapid intravascular
cooling done in situ, followed by removal of the organs, storage of
the organs in ice-cold preservation fluid and rapid transport to
the recipients' hospitals. The cold ischemic time is the length of
time the organs are on ice, without blood flow. The maximum cold
ischemic time limits the amount of time that can pass between organ
recovery and the organ transplant (Table 5). Between 2%-10% of
matched and procured organs cannot be used due to extended ischemic
time, depending on the type of organ. Similarly, approximately 10
to 20% of procured organs are not used due to poor organ function
and/or infection (not including HIV/CMV/hepatitis).
[0504] Current preservation techniques involve the use of ice-cold
solutions that include electrolytes, antioxidants, hydrogen ion
buffers and sugars. Punch et al., 2001. Appropriate tissue matching
depends on blood group matching (e.g., blood type, A, B or O) for
all organs. Immunosuppresive regimens typically include three
drugs: a glucocorticoid such as prednisone, an antimetabolite such
as azathiprine or mycophenolate, and a calcineurin inhibitor such
as cyclosporine or tacrolimus.
[0505] The two most frequently used methods for
preserving/transporting hearts for transplantation are hypothermic
storage and continuous perfusion. In the former method, the heart
is arrested, removed from the donor, and then rapidly cooled and
transported in cold storage. In the latter method, the following
steps are typically employed: 1) pulsatile flow; 2) hypothermia; 3)
membrane oxygenation, and 4) a perfusate containing both.
[0506] To improve the prospect of a successful transplant,
techniques for better preserving an organ for transplantation have
been developed. Two general areas of development have occurred, one
in the area of preservation solutions and the other in the area of
organ containers.
[0507] In certain contexts, such as transplant, adverse
consequences of wound healing may impair or prevent proper
engraftment of transplanted tissue. In the context of the present
invention, it is envisioned that donated and recipient tissues will
be treated pre-transplantation with an oxygen antagonist or other
active compound, as discussed above with respect to wound healing,
in an effort to inhibit biological processes such as inflammation,
apoptosis and other wound healing/post-transplantation events that
damage engrafted tissues.
[0508] F. Organisms
[0509] Such organisms could be used for research purposes, such as
laboratory mice (mouse banking), or for consumption, such as fish.
In these situation, it is contemplated that stasis can be
maintained indefinitely. Moreover, stasis can be induced in plants
or parts of plants, including fruit, flowers, leaves, stems, seeds,
cuttings. Plants can be agricultural, medicinal, or decorative.
Induction of stasis in plants may enhance the shelf life or
pathogen resistance of the whole or part of the plant. Thus, in
embodiments of the invention, an organism or part thereof can be
exposed to an oxygen antagonist or other active compound for about,
at least about, or at most about 30 seconds, 1, 2, 3, 4, 5, 10, 15,
20, 25, 30, 35, 40, 45, 50, 55 minutes, 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 hours,
1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12 months, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
14, 15, 16, 17, 18, 19, 20 or more years, and any combination or
range derivable therein.
[0510] G. Preservation Agents
[0511] A variety of preservation solutions have been disclosed in
which the organ is surrounded or perfused with the preservation
solution while it is transported. One of the most commonly used
solution is ViaSpan.RTM. (Belzer UW), which employed with cold
storage. Other examples of such solutions or components of such
solutions include the St. Thomas solution (Ledingham et al., J.
Thorac. Cardiobasc. Surg. 93:240-246, 1987), Broussais solution, UW
solution (Ledingham et al., Circulation 82 (Part 2)IV351-8, 1990),
Celsior solution (Menasche et al., Eur. J. Cardio. Thorax. Surg.
8:207-213, 1994), Stanford University solution, and solution B20
(Bernard et al., J. Thorac. Cardiovasc. Surg. 90:235-242, 1985), as
well as those described and/or claimed in U.S. Pat. Nos. 6,524,785;
6,492,103; 6,365,338; 6,054,261; 5,719,174; 5,693,462; 5,599,659;
5,552,267; 5,405,742; 5,370,989; 5,066,578; 4,938,961; and,
4,798,824.
[0512] In addition to solutions, other types of materials are also
known for use in transporting organs and tissue. These include
gelatinous or other semi-solid material, such as those described,
for example, in U.S. Pat. No. 5,736,397.
[0513] Some of the systems and solutions for organ preservation
specifically involve oxygen perfusion in the solution or system to
expose the organ to oxygen because it is believed that maintaining
the organ or tissue in an oxygenated environment improves
viability. See Kuroda et al., (Transplantation 46(3):457-460, 1988)
and U.S. Pat. Nos. 6,490,880; 6,046,046; 5,476,763; 5,285,657;
3,995,444; 3,881,990; and, 3,777,507. Isolated hearts that are
deprived of oxygen for more than four hours are believed to lose
vigor and not be useful in the recipient because of
ischemic/reperfusion injury. See U.S. Pat. No. 6,054,261.
[0514] Moreover, many, if not all, of the solutions and containers
for organ preservation and transplantation involve hypothermia
(temperature below room temperature, often near but not below
0.degree. C.), which has been called the "bed rock of all useful
methods of organ and tissue preservation." U.S. Pat. No.
6,492,103.
[0515] To improve the prospect of a successful transplant,
techniques for better preserving an organ for transplantation have
been developed. Two general areas of development have occurred, one
in the area of preservation solutions and the other in the area of
organ containers.
[0516] Moreover, many, if not all, of the solutions and containers
for organ preservation and transplantation involve hypothermia
(temperature below room temperature, often near but not below
0.degree. C.), which has been called the "bed rock of all useful
methods of organ and tissue preservation." U.S. Pat. No.
6,492,103.
[0517] In the field of organ transplantation, certain conditions
are believed to be related to the condition of the organ and
prognosis for a successful transplantation: 1) minimization of cell
swelling and edema; 2) prevention of intracellular acidosis; 3)
minimization of ischemic damage; and 4) provision of substrate for
regeneration of high energy phosphate compounds and ATP during
reperfusion. Ischemic/reperfusion injury in organ transplantation
is especially problematic because the harvested organ is removed
from the body, isolated from a blood source, and thereby deprived
of oxygen and nutrients for an extended period of time (U.S. Pat.
No. 5,912,019). In fact, one of the most critical problems in
transplantation today is the relatively high incidence of delayed
graft function (DGF) due to acute tubular necrosis (ATN) after
surgery. Current methods still experience problems in these areas,
which highlights the importance of the present invention.
[0518] Nonetheless, the present invention can be used in
conjunction with other preservation compositions and methods. As
discussed in U.S. Pat. Nos. 5,952,168, 5,217,860, 4,559,258 and
6,187,529 (incorporated specifically by reference), biological
materials can be preserved, for example, for keeping transplantable
or replaceable organs long-term.
[0519] Cells, tissue/organs, or cadavers can be given compounds
that enhance or maintain the condition of organs for
transplantation. Such methods and compositions include those
described in U.S. Pat. Nos. 5,752,929 and 5,395,314.
[0520] Moreover, methods of the present invention can include
exposing biological matter to preservation solutions, such as those
discussed, in addition to exposure to an oxygen antagonist or other
active compound.
[0521] It is contemplated that any agent or solution used with a
biological sample that is living and that will be used as a living
material will be pharmaceutically acceptable or pharmacologically
acceptable. The phrase "pharmaceutically-acceptable" or
"pharmacologically-acceptable" refers to molecular entities and
compositions that do not produce an allergic or similar untoward
reaction when administered to a human. The preparation of an
aqueous composition that contains a protein as an active ingredient
is well understood in the art. Typically, such compositions are
prepared either as liquid solutions or suspensions; solid forms
suitable for solution in, or suspension in, liquid prior to use can
also be prepared.
[0522] Organs for transplants may be monitored to assess their
condition, particularly with respect to use as a transplant. Such
methods are described in U.S. Pat. No. 5,699,793.
[0523] A number of drugs can be administered to a patient after
receiving an organ transplant to assist in the recovery process.
Such drugs include compounds and agents that reduce or inhibit an
immune response against the donated organ.
[0524] Moreover, additional drugs are continually being researched
and offered for use in organ transplants, such as those described
in U.S. Pat. No. 6,552,083 (inhibitory agent comprising
N-(3,4-dimethoxycinnamoyl)anthranililc acid) and U.S. Pat. No.
6,013,256 (antibodies that bind the IL-2 receptor, such as a
humanized anti-Tax antibody).
[0525] H. Preservation Apparatuses and Applications
[0526] Systems or containers for transporting organs and tissues
have also been developed through the years. Any of these
embodiments may be combined with apparatuses of the invention,
which allow for use with oxygen antagonists or other active
compound.
[0527] Most involve cooling systems for implementation, for
example, those described in U.S. Pat. Nos. 4,292,817, 4,473,637,
and 4,745,759, which employ active refrigeration with a cooling
liquid that is pumped through the system. Several sophisticated
devices have been designed involving multiple chambers or dual
containers, such as is U.S. Pat. Nos. 5,434,045 and 4,723,974.
[0528] Some constitute a system in which an apparatus is devised
for perfusion of the organ or tissue in a preservation solution, as
is described in U.S. Pat. Nos. 6,490,880; 6,100,082; 6,046,046;
5,326,706; 5,285,657; 5,157,930; 4,951,482; 4,502,295; and,
4,186,565.
[0529] Some of the systems and solutions for organ preservation
specifically involve oxygen perfusion in the solution or system to
expose the organ to oxygen because it is believed that maintaining
the organ or tissue in an oxygenated environment improves
viability. See Kuroda et al., (Transplantation 46(3):457-460, 1988)
and U.S. Pat. Nos. 6,490,880; 6,046,046; 5,476,763; 5,285,657;
3,995,444; 3,881,990; and, 3,777,507. Isolated hearts that are
deprived of oxygen for more than four hours are believed to lose
vigor and not be useful in the recipient because of
ischemic/reperfusion injury. See U.S. Pat. No. 6,054,261.
[0530] Moreover, in some embodiments of the invention, there are
methods for preserving platelets, as mentioned above. Shortcomings
of the prior art are reduced or eliminated using techniques of this
disclosure. Embodiments concerning platelets and oxygen reduction
find wide application including but not limited to any application
that would benefit from longer-lasting storage of platelets.
[0531] In one embodiment, oxygen reduction techniques can be
embodied in a kit. For example, the kit currently sold under
product number 261215, available from Becton Dickinson, makes use
of select techniques described here. That kit includes an anaerobic
generator (e.g., a hydrogen gas generator), Palladium Catalysts, an
anaerobic indicator, and a gas impermeable, sealable, "BioBag" into
which the above components (together with platelets in a
gas-permeable bag) are placed and sealed.
[0532] The anaerobic generator of this example kit is activated by
the addition of water, which passes through a series of channels to
a filter paper wick. The wick delays and regulates the introduction
of water into the tablet chamber, providing a controlled release of
hydrogen gas. The gas-generating tablet includes sodium
borohydride. The hydrogen released from this reaction combines with
the atmospheric oxygen in the sealed container to produce water.
This reaction is catalyzed by the palladium in the container.
[0533] In a more general respect, techniques of this disclosure can
be carried out using any number of sealed environments (e.g., a
container such as a jar, impermeable bag, or chamber) in which
oxygen tension can be reduced. In one embodiment, an oxygen level
within the container and/or within platelets or an associated
solution may be reduced to less than about 1% (about 10,000 parts
per million). In another embodiment, the oxygen may be reduced to
about a range of 10-100 parts per million, or less. In still other
embodiments, the oxygen may be reduced to any percentage value that
represents a decrease in oxygen within a container and/or within
platelets or an associated solution. In preferred embodiments, the
container is gas-impermeable, as well as sealable. As those having
ordinary skill in the art will appreciate "gas impermeable" does
not necessarily connote an absolute or 100% level of
impermeability. Rather, "gas impermeable" should be interpreted as
it is in the art to signify, e.g., able to hold an atmosphere that
is less than 10 ppm (against a gradient of room air, typically
210,000 ppm) for at least 4 days. Typically, commercially available
bags are impermeable for 6 weeks or longer.
[0534] A container may be sealed once pertinent oxygen reducing
elements are placed inside. The reduction in atmospheric oxygen in
this environment may be achieved by the generation of hydrogen gas,
with or without a catalyst, to combine with the oxygen to produce
water. Other reactions may be catalyzed to combine the oxygen with
other compounds, such as carbon to produce carbon dioxide. Other
reactions and combinations will be apparent to those having
ordinary skill in the art. Also, oxygen may be replaced by
exchanging gases in the chamber with gas containing any combination
of gases that do not include oxygen. Additionally, oxygen may be
removed by placing a container under a vacuum sufficient to remove
gases and particularly sufficient to remove oxygen to a desired,
reduced level. Alternatively, oxygen may be competed by using
another gas or compound that competes for oxygen, such as CO. A
combination of removal of oxygen and competition of remaining
oxygen may be used.
[0535] In different embodiments, a device may be used to measure
oxygen levels to ensure the appropriate anaerobic state has been
achieved. An anaerobic indicator based on methlyene blue that
changes from blue color to colorless in the absence of oxygen may
be used. Alternatively, a commercially available oxygen meter
(e.g., a mechanical and/or electrical meter) or other oxygen
measuring device may be used.
[0536] In different embodiments, platelets are contained in a
sealed environment such that oxygen can be removed from the
solution containing the platelets, as well as from the platelets
themselves. For example, platelets in a gas-permeable bag may be
placed inside a sealed environment. Other non-limiting examples may
be to have an open container inside a sealed environment to hold
platelets. Alternatively, one may contain platelets in an
impermeable, sealed container (e.g., a bag) and have an oxygen
removal mechanism incorporated.
[0537] In one embodiment, the invention involves a method in which
platelets and a solution are introduced into a gas-impermeable
container. The container is sealed. Oxygen is removed from the
container or from the platelets and solution. It is contemplated
that about, at least about, or at most about 20, 21, 22, 23, 24,
25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,
42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58,
59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75,
76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,
93, 94, 95, 96, 97, 98, 99, or 100%, or any range derivable
therein, of the oxygen in the gas permeable bag is removed.
[0538] This method may also include indicating a remaining oxygen
level within the container following oxygen removal. Oxygen in the
container may be reduced to a level of about 10,000 parts per
million or less. Oxygen in the container may be reduced to a level
between about 10 and about 100 parts per million. Introducing the
platelets may involve inserting a gas-permeable container holding
the platelets and solution into the gas-impermeable container.
Introducing the platelets may involve inserting the platelets and
solution into a sealable, flexible bag or a sealable, rigid
chamber. Sealing the container, which can occur at any stage of a
given process, can involve the use of an adhesive.
[0539] Removing oxygen may involve pumping oxygen from the
container, and such pumping may involve pumping with a roughing
and/or turbo pump. Removing oxygen may involve introducing hydrogen
into the container, which combines with the oxygen to produce
water. The hydrogen may be introduced through a chemical reaction.
The chemical reaction may be catalyzed. Removing oxygen may involve
introducing hydrogen into the container using a gas generating
tablet. Water may be added to a gas generating tablet comprising
sodium borohydride to generate hydrogen. Such water may be added in
a delayed and regulated manner. For example, a filter paper wick
may be used. Water may be introduced to the filter paper wick
through one or more channels. Palladium may catalyze a chemical
reaction that generates hydrogen. Removing oxygen may involve
introducing one or more agents into the container that bond with
the oxygen. CO may be introduced into the container, which bonds
with the oxygen to form CO.sub.2. Removing oxygen may involve
displacing oxygen with one or more gases -
[0540] Indicating a remaining oxygen level may involve use of a
methlyene blue indicator that changes color in the absence of
oxygen. Alternatively, an oxygen meter may be used. Indicating a
remaining oxygen level within the container may involve indicating
a remaining oxygen level within platelets or a solution.
[0541] In one embodiment, the invention involves a method in which
platelets and a solution are introduced into a gas-impermeable
container. The container is sealed. Hydrogen is generated through a
chemical reaction by adding water to sodium borohydride. The
chemical reaction removes oxygen from the platelets and solution
through combination with the hydrogen to form water. A remaining
oxygen level is indicated within the container following oxygen
removal.
[0542] The chemical reaction may be catalyzed using palladium. The
addition of water may involve use of a filter paper wick.
[0543] In one embodiment, the invention involves a system for
removing oxygen from platelets and a solution. The system includes
(a) a sealable, gas-impermeable container, (b) an oxygen-reducing
generator, and (c) an oxygen indicator. The sealable,
gas-impermeable container is configured and sized to receive the
platelets and the solution. The oxygen-reducing generator is
coupled to the container and is configured to remove oxygen from
the platelets and the solution through pumping or chemical
reaction. The oxygen indicator is coupled to the container and is
configured to indicate an oxygen level within the container
following oxygen removal.
[0544] The container may be a sealable, flexible bag. The oxygen
reducing generator may include a hydrogen generator configured to
generate hydrogen for combining with the oxygen to produce water.
The hydrogen generator may include a gas generating substance that,
when combined with an agent, generates the hydrogen. That gas
generating substance may include a sodium borohydride tablet, and
the agent may include water. A hydrogen generator may also include
a palladium catalyst. The system may also include a member
configured to delay or regulate a chemical reaction by controlling
the introduction of one or more components of the chemical
reaction. For example, the member can include a wick that delays
and regulates a chemical reaction.
[0545] In one embodiment, the invention involves a kit including a
hydrogen generator; a gas impermeable, sealable container; and an
oxygen indicator.
[0546] The hydrogen generator may include a gas generating
substance that, when combined with an agent, generates the
hydrogen. That gas generating substance may include a sodium
borohydride tablet, and the agent may include water. The kit may
also include a palladium catalyst. The kit may also include a wick
configured to delay or regulate a chemical reaction that generates
the hydrogen.
[0547] As discussed above, methods of the invention can involve
employing an apparatus or system that maintains the environment in
which biological matter is placed or exposed to. The invention
includes an apparatus in which an active compound, particularly as
a gas, is supplied. In some embodiments, the apparatus includes a
container with a sample chamber for holding the biological matter,
wherein the container is connected to a supply of gas comprising
the active compound(s). It is specifically contemplated that the
container may be a solid container or it may flexible, such as a
bag.
[0548] In some embodiments, the invention is an apparatus for
preserving cell(s), the apparatus comprising: a container having a
sample chamber with a volume of no greater than 775 liters; and a
first gas supply in fluid communication with the sample chamber,
the first gas supply including carbon monoxide. In further
embodiments, the apparatus also includes a cooling unit that
regulates the temperature inside the sample chamber and/or a gas
regulator that regulates the amount of active compound in the
chamber or the amount of active compound in a solution that is in
the chamber.
[0549] It is contemplated that there may be a gas supply for a
second or additional gas or a second or additional gas supply for
the active compound. The second gas supply may be connected with
the sample chamber or it may be connected with the first gas
supply. The additional gas, as discussed above, may be a non-toxic
and/or non-reactive gas.
[0550] A gas regulator is part of the apparatus in some embodiments
of the invention. One, two, three, or more gas regulators may be
employed. In some cases, the gas regulator regulates the gas
supplied to the sample chamber from the first gas supply.
Alternatively, it regulates the gas supplied to the sample chamber
or first gas supply from the second gas supply, or there may be a
regulator for both the first and second gas supplies. It is further
contemplated that any gas regulator can be programmed to control
the amount of gas supplied to the sample chamber and/or to another
gas supply. The regulation may or may not be for a specified period
of time. There may be a gas regulator, which may or may not be
programmable, for any gas supply directly or indirectly connected
to the sample chamber. In some cases, the gas regulator is
electronically programmable.
[0551] In some cases, the pressure and/or the temperature inside
the chamber can be regulated with either a pressure regulator or
temperature regulator, respectively. As with the gas regulator,
these regulators may be electronically programmable. The apparatus
of the invention may also have a cooling and/or heating unit to
achieve the temperatures discussed above. The unit may or may not
be electronically programmable.
[0552] In additional embodiments, the apparatus includes a wheeled
cart on which the container rests or it may have one or more
handles.
[0553] It is specifically contemplated that the invention includes
an apparatus for cell(s), in which the apparatus has: a container
having a sample chamber; a first gas supply in fluid communication
with the sample chamber, the first gas supply including the active
compound(s); and an electronically-programmable gas regulator that
regulates gas supplied to the sample chamber from the first gas
supply.
[0554] In some embodiments, the apparatus also has a structure
configured to provide a vacuum within the sample chamber.
[0555] Moreover, any oxygen antagonist described in this
application is contemplated for use with apparatuses of the
invention. In specific embodiments, carbon monoxide can be
administered using this apparatus. In other cases, a chalcogenide
compound can be administered or a compound having the reducing
agent structure.
[0556] FIG. 19 is a schematic diagram of an example system for
removing oxygen from platelets and a solution and embodies concepts
discussed above. Gas permeable bag 1902 may be placed in sealable
gas impermeable container 1904. Gas impermeable container 1904 may
be coupled to oxygen reducing generator 1906. Oxygen reducing
generator 1906, in one embodiment, may envelope sealable gas
impermeable container 1904. In different embodiments, oxygen
reducing generator 1906 may take different forms. For example, it
may be a pump (e.g., a roughing or and/or turbo pump) or a hydrogen
generator. Associated with oxygen reducing generator 1906 may be
one or more components such as a wick or other delay mechanism.
Coupled to sealable gas impermeable container 1904 are sensor 1908
and regulator 1910. Sensor 1908, in one embodiment, may be an
oxygen meter, which may take various forms. In other embodiments,
sensor 1908 may be a temperature or pressure meter. Of course, more
than one sensor may be used. In one embodiment, regulator 1901 may
be a temperature or pressure regulator. For example, regulator 1901
may be a heater or cooling device to regulate temperature inside
sealable gas impermeable container 1904.
V. Diagnostic Applications
[0557] Sulfites are produced by all cells in the body during normal
metabolism of sulfur containing amino acids. Sulfite oxidase,
removes, and thus regulates the levels of sulfites. Differential
activities of these enzymes would lead to different levels of
sulfites evolved in tissue specific manner. In the example
described above, for solid tumors in hypoxic conditions, sulfites
may be produced at higher levels to provide local protective state
to the tumor cells through the reduction of metabolic state as well
as the inhibition of immune surveillance. Therefore, it would be
beneficial to measure sulfite levels and incorporate this as part
of diagnosis for several disease states such as solid tumors.
Furthermore, since we propose using sulfites for various
applications, it would be useful to follow this using some sort of
imaging or other monitoring process.
[0558] It is possible to measure sulfite levels in serum to get a
total sulfite level using current technology (e.g., HPLC). It is
worth exploring the possibility of imaging sulfites. Alternatively,
a proteomic approach may allow an understanding of how the
regulation of the enzymes involved in sulfite metabolism may be
altered in certain disease states, allowing for this approach to
diagnostics.
VI. Screening Applications
[0559] In still further embodiments, the present invention provides
methods for identifying oxygen antagonists and molecules that act
in a like fashion with respect to inducing stasis and other active
compounds. In some cases, the oxygen antagonist or active compounds
being sought works like a chalcogenide compound in reducing core
body temperature or preserving viability in hypoxic or anoxic
environments that would otherwise kill the biological matter if it
were not for the presence of the oxygen antagonist or other active
compound. These assays may comprise random screening of large
libraries of candidate substances; alternatively, the assays may be
used to focus on particular classes of compounds selected with an
eye towards attributes that are believed to make them more likely
to act as oxygen antagonists or active compounds. providing a
candidate active compound; [0560] (a) admixing the candidate active
compound with a biological matter; [0561] (b) measuring one or more
cellular responses characteristic of oxygen antagonist treatment;
and [0562] (c) comparing the one or more responses with the
biological matter in the absence of the candidate active compound.
Assays may be conducted with isolated cells, tissues/organs, or
intact organisms.
[0563] It will, of course, be understood that all the screening
methods of the present invention are useful in themselves
notwithstanding the fact that effective candidates may not be
found. The invention provides methods for screening for such
candidates, not solely methods of finding them. However, it will
also be understand that candidate active compound may be identified
as an effective active compound according to one or more assays,
meaning that the candidate active compound appears to have some
ability to act as an active compound, such as by inducing stasis in
a biological matter. Screening, in some embodiments, involves using
an assay described in the Examples or elsewhere in the disclosure
to identify a modulator. Moreover, in addition to or instead of the
method described in this section, a candidate active compound may
be tested for activity either as an oxygen antagonist or as another
compound having a property of an active compound, such as
protective metabolic agent or therapeutic substance. Some
embodiments of screening methods are provided above.
[0564] An effective active compound may be further characterized or
assayed. Moreover, the effective active compound may be used in an
in vivo animal or animal model (as discussed below) or be used in
further in vivo animals or animal models, which may involve the
same species of animals or in different animal species.
[0565] Furthermore, it is contemplated that an active compound
identified according to embodiments of the invention may also be
manufactured after screening. Also, biological matter may be
exposed to or contacted with an effective active compound according
to methods of the invention, particularly with respect to
therapeutic or preservation embodiments.
[0566] A. Active Compounds
[0567] As used herein the term "candidate active compound" refers
to any molecule that may induce stasis in biological matter by, for
example, altering core body temperature. The candidate active
compound may be a protein or fragment thereof, a small molecule, or
even a nucleic acid molecule. One may also acquire, from various
commercial sources, small molecule libraries that are believed to
meet the basic criteria for useful drugs in an effort to "brute
force" the identification of useful compounds. Screening of such
libraries, including combinatorially generated libraries (e.g.,
peptide libraries), is a rapid and efficient way to screen large
number of related (and unrelated) compounds for activity.
Combinatorial approaches also lend themselves to rapid evolution of
potential drugs by the creation of second, third and fourth
generation compounds modeled of active, but otherwise undesirable
compounds.
[0568] Candidate active compounds may include fragments or parts of
naturally-occurring compounds, or may be found as active
combinations of known compounds, which are otherwise inactive. It
is proposed that compounds isolated from natural sources, such as
animals, bacteria, fungi, plant sources, including leaves and bark,
and marine samples may be assayed as candidates for the presence of
potentially useful pharmaceutical agents. It will be understood
that the pharmaceutical agents to be screened could also be derived
or synthesized from chemical compositions or man-made compounds.
Thus, it is understood that the candidate active compound
identified by the present invention may be peptide, polypeptide,
polynucleotide, small molecule inhibitors or any other compounds
that may be designed through rational drug design starting from
known inhibitors or stimulators.
[0569] Other suitable active compounds include antisense molecules,
siRNAs, ribozymes, and antibodies (including single chain
antibodies), each of which would be specific for the target
molecule. Such compounds are described in greater detail elsewhere
in this document. For example, an antisense molecule that bound to
a translational or transcriptional start site, or splice junctions,
would be ideal candidate inhibitors.
[0570] In addition to the active compounds initially identified,
the inventor also contemplates that other structurally similar
compounds may be formulated to mimic the key portions of the
structure of the active compounds. Such compounds, which may
include peptidomimetics of peptide modulators, may be used in the
same manner as the initial active compounds.
[0571] B. In vivo Assays
[0572] In vivo assays involve the use of various animal models. Due
to their size, ease of handling, and information on their
physiology and genetic make-up, mice are a preferred embodiment.
However, other animals are suitable as well, including rats,
rabbits, hamsters, guinea pigs, gerbils, woodchucks, mice, cats,
dogs, sheep, goats, pigs, cows, horses and monkeys (including
chimps, gibbons and baboons). Fish are also contemplated for use
with in vivo assays, as are nematodes. Assays for modulators may be
conducted using an animal model derived from any of these
species.
[0573] In such assays, one or more candidate substances are
administered to an animal, and the ability of the candidate
substance(s) to induce stasis, reduce core body temperature, or
endow on the biological material the ability to survive hypoxic or
anoxic environmental conditions, as compared to an inert vehicle
(negative control) and H.sub.2S (positive control), identifies a
modulator. Treatment of animals with test compounds will involve
the administration of the compound, in an appropriate form, to the
animal. Administration of the candidate compound (gas or liquid)
will be by any route that could be utilized for clinical or
non-clinical purposes, including but not limited to oral, nasal
(inhalation or aerosol), buccal, or even topical. Alternatively,
administration may be by intratracheal instillation, bronchial
instillation, intradermal, subcutaneous, intramuscular,
intraperitoneal or intravenous injection. Specifically contemplated
routes are systemic intravenous injection, regional administration
via blood or lymph supply, or directly to an affected site.
VII. Modes of Administration and Pharmaceutical Compositions
[0574] An effective amount of a pharmaceutical composition of a
chalcogenide, oxygen antagonist, or the active compound, generally,
is defined as that amount sufficient to detectably ameliorate,
reduce, minimize or limit the extent of the condition of interest.
More rigorous definitions may apply, including elimination,
eradication or cure of disease.
[0575] A. Administration
[0576] The routes of administration of a chalcogenide or other
active compound will vary, naturally, with the location and nature
of the condition to be treated, and include, e.g., inhalation,
intradermal, transdermal, parenteral, intravenous, intramuscular,
intranasal, subcutaneous, percutaneous, intratracheal,
intraperitoneal, intratumoral, perfusion, lavage, direct injection,
and oral administration and formulation. As detailed below, active
compounds may be administered as medical gases by inhalation or
intubation, as injectable liquids by intravascular, intravenous,
intra-arterial, intracerobroventicular, intraperitoneal,
subcutaneous administration, as topical liquids or gels, or in
solid oral dosage forms.
[0577] Moreover, the amounts may vary depending on the type of
biological matter (cell type, tissue type, organism genus and
species, etc.) and/or its size (weight, surface area, etc.). It
will generally be the case that the larger the organism, the larger
the dose. Therefore, an effective amount for a mouse will generally
be lower than an effective amount for a rat, which will generally
be lower than an effective amount for a dog, which will generally
be lower than an effective amount for a human. The effective
concentration of hydrogen sulfide to achieve stasis in a human
depends on the dosage form and route of administration. For
inhalation, in some embodiments effective concentrations are in the
range of 50 ppm to 500 ppm, delivered continuously. For intravenous
administration, in some embodiments effective concentrations are in
the range of 0.5 to 50 milligrams per kilogram of body weight
delivered continuously.
[0578] Similarly, the length of time of administration may vary
depending on the type of biological matter (cell type, tissue type,
organism genus and species, etc.) and/or its size (weight, surface
area, etc.) and will depend in part upon dosage form and route of
administration. In particular embodiments, an active compound is
provided for about or at least 30 seconds, 1 minute, 2 minutes, 3
minutes, 5 minutes, 10 minutes, 15 minutes, 30 minutes, 1 hour, 2
hours, 3 hours, four hours five hours, six hours, eight hours,
twelve hours, twenty-four hours, or greater than twenty-four hours.
An active compound may be administered in a single dos or multiple
doses, with varying amounts of time between administered doses.
[0579] In the case of transplant, the present invention may be used
pre- and or post-operatively to render host or graft materials
quiescent. In a specific embodiment, a surgical site may be
injected or perfused with a formulation comprising a chalcogenide.
The perfusion may be continued post-surgery, for example, by
leaving a catheter implanted at the site of the surgery.
[0580] B. Injectable Compositions and Formulations
[0581] The preferred methods for the delivery of oxygen antagonists
or other active compound of the present invention are inhalation,
intravenous injection, perfusion of a particular area, and oral
administration. However, the pharmaceutical compositions disclosed
herein may alternatively be administered parenterally,
intradermally, intramuscularly, transdermally or even
intraperitoneally as described in U.S. Pat. No. 5,543,158; U.S.
Pat. No. 5,641,515 and U.S. Pat. No. 5,399,363 (each specifically
incorporated herein by reference in its entirety).
[0582] Solutions of the active compounds may be prepared in water
suitably mixed with a surfactant, such as hydroxypropylcellulose.
Dispersions may also be prepared in glycerol, liquid polyethylene
glycols, and mixtures thereof and in oils. Under ordinary
conditions of storage and use, these preparations contain a
preservative to prevent the growth of microorganisms. The
pharmaceutical forms suitable for injectable use include sterile
aqueous solutions or dispersions and sterile powders for the
extemporaneous preparation of sterile injectable solutions or
dispersions (U.S. Pat. No. 5,466,468, specifically incorporated
herein by reference in its entirety). In all cases the form must be
sterile and must be fluid to the extent that easy syringability
exists. It must be stable under the conditions of manufacture and
storage and must be preserved against the contaminating action of
microorganisms, such as bacteria and fungi. The carrier can be a
solvent or dispersion medium containing, for example, water,
ethanol, polyol (e.g., glycerol, propylene glycol, and liquid
polyethylene glycol, and the like), suitable mixtures thereof,
and/or vegetable oils. Proper fluidity may be maintained, for
example, by the use of a coating, such as lecithin, by the
maintenance of the required particle size in the case of dispersion
and by the use of surfactants. The prevention of the action of
microorganisms can be brought about by various antibacterial and
antifungal agents, for example, parabens, chlorobutanol, phenol,
sorbic acid, thimerosal, and the like. In many cases, it will be
preferable to include isotonic agents, for example, sugars or
sodium chloride. Prolonged absorption of the injectable
compositions can be brought about by the use in the compositions of
agents delaying absorption, for example, aluminum monostearate and
gelatin.
[0583] For parenteral administration in an aqueous solution, for
example, the solution should be suitably buffered if necessary and
the liquid diluent first rendered isotonic with sufficient saline
or glucose. These particular aqueous solutions are especially
suitable for intravenous, intramuscular, subcutaneous, intratumoral
and intraperitoneal administration. In this connection, sterile
aqueous media that can be employed will be known to those of skill
in the art in light of the present disclosure. For example, one
dosage may be dissolved in 1 ml of isotonic NaCl solution and
either added to 1000 ml of hypodermoclysis fluid or injected at the
proposed site of infusion, (see for example, "Remington's
Pharmaceutical Sciences" 15th Edition, pages 1035-1038 and
1570-1580). Some variation in dosage will necessarily occur
depending on the condition of the subject being treated. The person
responsible for administration will, in any event, determine the
appropriate dose for the individual subject. Moreover, for human
administration, preparations should meet sterility, pyrogenicity,
general safety and purity standards as required by FDA Office of
Biologics standards.
[0584] Sterile injectable solutions are prepared by incorporating
the active compounds in the required amount in the appropriate
solvent with various other ingredients enumerated above, as
required, followed by filtered sterilization. Generally,
dispersions are prepared by incorporating the various sterilized
active ingredients into a sterile vehicle which contains the basic
dispersion medium and the required other ingredients from those
enumerated above. In the case of sterile powders for the
preparation of sterile injectable solutions, the preferred methods
of preparation are vacuum-drying and freeze-drying techniques which
yield a powder of the active ingredient plus any additional desired
ingredient from a previously sterile-filtered solution thereof.
[0585] As used herein, "carrier" includes any and all solvents,
dispersion media, vehicles, coatings, diluents, antibacterial and
antifungal agents, isotonic and absorption delaying agents,
buffers, carrier solutions, suspensions, colloids, and the like.
The use of such media and agents for pharmaceutical active
substances is well known in the art. Except insofar as any
conventional media or agent is incompatible with the active
ingredient, its use in the therapeutic compositions is
contemplated. Supplementary active ingredients can also be
incorporated into the compositions.
[0586] The phrase "pharmaceutically-acceptable" or
"pharmacologically-acceptable" refers to molecular entities and
compositions that do not produce an allergic or similar untoward
reaction when administered to a human. The preparation of an
aqueous composition that contains a protein as an active ingredient
is well understood in the art. Typically, such compositions are
prepared as injectables, either as liquid solutions or suspensions;
solid forms suitable for solution in, or suspension in, liquid
prior to injection can also be prepared.
[0587] C. Intravenous Formulations
[0588] In one embodiment, active compounds of the invention may be
formulated for parenteral administration (e.g., intravenous,
intra-arterial). In the cases where the active compound is a gas at
room temperature, a solution containing a known and desired
concentration of the gas molecule dissolved in a liquid or a
solution for parenteral administration is contemplated. Preparation
of the active compound solution may be achieved by, for example,
contacting (e.g., bubbling or infusing) the gas with the solution
to cause the gas molecules to dissolve in the solution. Those
skilled in the art will recognize that the amount of gas that
dissolves in the solution will depend on a number of variables
including, but not limited to, the solubility of the gas in the
liquid or solution, the chemical composition of the liquid or
solution, its temperature, its pH, its ionic strength, as well as
the concentration of the gas and the extent of contacting (e.g.,
rate of and duration of bubbling or infusing). The concentration of
the active compound in the liquid or solution for parenteral
administration can be determined using methods known to those
skilled in the art. The stability of the active compound in the
liquid or solution can be determined by measuring the concentration
of the dissolved oxygen antagonist after varying intervals of time
following preparation or manufacture of the oxygen antagonist
solution, where a decrease in the concentration of the oxygen
antagonist compared to the starting concentration is indicative of
loss or chemical conversion of the active compound.
[0589] In some embodiments, there is a solution containing a
chalcogenide compound is produced by dissolving a salt form of the
chalcogenide into sterile water or saline (0.9% sodium chloride) to
yield a pharmaceutically acceptable intravenous dosage form. The
intravenous liquid dosage form may be buffered to a certain pH to
enhance the solubility of the chalcogenide compound or to influence
the ionization state of the chalcogenide compound. In the cases of
hydrogen sulfide or hydrogen selenide, any of a number of salt
forms known to those skilled in the art may suffice, including, but
not limited to, sodium, calcium, barium, lithium, or potassium. In
another preferred embodiment, sodium sulfide or sodium selenide is
dissolved in sterile phosphate buffered saline and the pH is
adjusted to 7.0 with hydrochloric acid to yield a solution of known
concentration which can be administered to a subject intravenously
or intrarterially.
[0590] It is contemplated that in some embodiments, a
pharmaceutical composition of the invention is a saturated solution
with respect to the active compound. The solution can be any
pharmaceutically acceptable formulation, many of which are well
known, such as Ringer's solution. In certain embodiments, the
concentration of the active compound is about, at least about, or
at most about 0.001, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07,
0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1,
1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4,
2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6,
3.7.3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0
M or more, or any range derivable therein (at standard temperature
and pressure (STP)). With H.sub.2S, for example, in some
embodiments, the concentration can be from about 0.01 to about 0.5
M (at STP). It is specifically contemplated the above
concentrations may be applied with respect to carbon monoxide and
carbon dioxide in a solution separately or together.
[0591] Furthermore, when administration is intravenous, it is
contemplated that the following parameters may be applied. A flow
rate of about, at least about, or at most about 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57,
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,
75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91,
92, 93, 94, 95, 96, 97, 98, 99, 100 gtts/min or .mu.tts/min, or any
range derivable therein. In some embodiments, the amount of the
solution is specified by volume, depending on the concentration of
the solution. An amount of time may be about, at least about, or at
most about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,
17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50,
51, 52, 53, 54, 55, 56, 57, 58, 59, 60 minutes, 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
hours, 1, 2, 3, 4, 5, 6, 7 days, 1, 2, 3, 4, 5 weeks, and/or 1, 2,
3, 4, 5, 6, 7, 8, 9, 10, 11, 12 months, or any range derivable
therein.
[0592] Volumes of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,
66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82,
83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99,
100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220,
230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350,
360, 370, 380, 390, 400, 410, 420, 430, 440, 441, 450, 460, 470,
480, 490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600,
610, 620, 630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730,
740, 750, 760, 770, 780, 790, 800, 810, 820, 830, 840, 850, 860,
870, 880, 890, 900, 910, 920, 930, 940, 950, 960, 970, 980, 990,
1000 mls or liters, or any range therein, may be administered
overall or in a single session.
[0593] In some embodiments, the solution of the active compound for
parenteral administration is prepared in a liquid or solution in
which the oxygen has been removed prior to contacting the liquid or
solution with the active compound. Certain oxygen antagonists, in
particular certain chalcogenide compounds (e.g., hydrogen sulfide,
hydrogen selenide), are not stable in the presence of oxygen due to
their ability to react chemically with oxygen, leading to their
oxidation and chemical transformation. Oxygen can be removed from
liquids or solutions using methods known in the art, including, but
not limited to, application of negative pressure (vacuum degasing)
to the liquid or solution, or contacting the solution or liquid
with a reagent which causes oxygen to be bound or "chelated",
effectively removing it from solution.
[0594] In another embodiment, the solution of the oxygen antagonist
or other active compound for parenteral administration may be
stored in a gas-tight container. This is particularly desirable
when the oxygen has previously been removed from the solution to
limit or prevent oxidation of the oxygen antagonist or other active
compound. Additionally, storage in a gas-tight container will
inhibit the volatilization of the oxygen antagonist gas or other
active compound from the liquid or solution, allowing a constant
concentration of the dissolved oxygen antagonist to be maintained.
Gas-tight containers are known to those skilled in the art and
include, but are not limited to, "i.v. bags" comprising a gas
impermeable construction material, or a sealed glass vial. To
prevent exposure to air in the gas-tight storage container, an
inert gas, such as nitrogen or argon, may be introduced into the
container prior to closure.
[0595] D. Topical Formulations and Uses Thereof
[0596] Methods and compositions of the present invention are useful
for inducing stasis in superficial layers of the skin and oral
mucosa, including, but not limited to, hair follicle cells,
capillary endothelial cells, and epithelial cells of the mouth and
tongue. Radiation therapy and chemotherapy for the treatment of
cancer damage normal cells in the hair follicles and oral mucosa,
leading to the unintended, but debilitating side effects of cancer
therapy, hair loss and oral mucositis, respectively. Induction of
stasis in hair follicle cells and/or the vascular cells that supply
blood to the hair follicles may slow, limit or prevent damage to
hair follicle cells and the resultant hair loss that accompanies
radiation therapy and chemotherapy, or other alopecia, male-pattern
baldness, female-pattern baldness, or other absence of the hair
from skin areas where it normally is present. Induction of stasis
in oral epithelial and mesenchymal cells may slow, limit or prevent
damage to cells lining the mouth, esophagus and tongue and the
resultant painful condition of oral mucositis.
[0597] In certain embodiments the active compound is administered
topically. This is achieved by formulating the active compound in a
cream, gel, paste, or mouthwash and applying such formulation
directly to the areas that require exposure to the active compound
(e.g., scalp, mouth, tongue, throat).
[0598] The topical compositions of this invention can be formulated
as oils, creams, lotions, ointments and the like by choice of
appropriate carriers. Suitable carriers include vegetable or
mineral oils, white petrolatum (white soft paraffin), branched
chain fats or oils, animal fats and high molecular weight alcohol
(greater than C.sub.12). The preferred carriers are those in which
the active ingredient is soluble. Emulsifiers, stabilizers,
humectants and antioxidants may also be included as well as agents
imparting color or fragrance, if desired. Additionally, transdermal
penetration enhancers can be employed in these topical
formulations. Examples of such enhancers can be found in U.S. Pat.
Nos. 3,989,816 and 4,444,762.
[0599] Creams are preferably formulated from a mixture of mineral
oil, self-emulsifying beeswax and water in which mixture the active
ingredient, dissolved in a small amount of an oil such as almond
oil, is admixed. A typical example of such a cream is one which
includes about 40 parts water, about 20 parts beeswax, about 40
parts mineral oil and about 1 part almond oil.
[0600] Ointments may be formulated by mixing a solution of the
active ingredient in a vegetable oil such as almond oil with warm
soft paraffin and allowing the mixture to cool. A typical example
of such an ointment is one which includes about 30% almond oil and
about 70% white soft paraffin by weight.
[0601] Lotions may be conveniently prepared by dissolving the
active ingredient, in a suitable high molecular weight alcohol such
as propylene glycol or polyethylene glycol.
[0602] Possible pharmaceutical preparations that can be used
rectally include, for example, suppositories, which consist of a
combination of one or more of the active compounds with a
suppository base. Suitable suppository bases are, for example,
natural or synthetic triglycerides, or paraffin hydrocarbons. In
addition, it is also possible to use gelatin rectal capsules which
consist of a combination of the active compounds with a base.
Possible base materials include, for example, liquid triglycerides,
polyethylene glycols, or paraffin hydrocarbons.
[0603] E. Solid Dosage Forms
[0604] Pharmaceutical compositions include solid dosage forms in
which the active compound is trapped, or sequestered, in a porous
carrier framework that is capable of achieving a crystalline, solid
state. Such solid dosage forms with the capacity for gas storage
are known in the art and can be produced in pharmaceutically
acceptable forms (e.g., Yaghi et al. 2003). A particular advantage
of such a pharmaceutical composition pertains to chalcogenide
compounds (e.g., hydrogen sulfide, carbon monoxide, hydrogen
selenide), which can be toxic to certain mammals at certain
concentrations in their free form. In certain embodiments, the
compound may be formulated for oral administration.
[0605] F. Perfusion Systems
[0606] A perfusion system for cells may be used to expose a tissue
or organ to an active compound in the form of a liquid or a
semi-solid. Perfusion refers to continuous flow of a solution
through or over a population of cells. It implies the retention of
the cells within the culture unit as opposed to continuous-flow
culture, which washes the cells out with the withdrawn media (e.g.,
chemostat). Perfusion allows for better control of the culture
environment (pH, pO.sub.2, nutrient levels, active compound levels,
etc.) and is a means of significantly increasing the utilization of
the surface area within a culture for cell attachment.
[0607] The technique of perfusion was developed to mimic the cells
milieu in vivo where cells are continuously supplied with blood,
lymph, or other body fluids. Without perfusion of a physiological
nutrient solution, cells in culture go through alternating phases
of being fed and starved, thus limiting full expression of their
growth and metabolic potential. In the context of the present
invention, a perfusion system may also be used to perfuse cells
with an oxygen antagonist to induce stasis.
[0608] Those of skill in the art are familiar with perfusion
systems, and there are a number of perfusion systems available
commercially. Any of these perfusion systems may be employed in the
present invention. One example of a perfusion system is a perfused
packed-bed reactor using a bed matrix of a non-woven fabric
(CelliGen.TM., New Brunswick Scientific, Edison, N.J.; Wang et al.,
1992; Wang et al., 1993; Wang et al., 1994). Briefly described,
this reactor comprises an improved reactor for culturing of both
anchorage- and non-anchorage-dependent cells. The reactor is
designed as a packed bed with a means to provide internal
recirculation. Preferably, a fiber matrix carrier is placed in a
basket within the reactor vessel. A top and bottom portion of the
basket has holes, allowing the medium to flow through the basket. A
specially designed impeller provides recirculation of the medium
through the space occupied by the fiber matrix for assuring a
uniform supply of nutrient and the removal of wastes. This
simultaneously assures that a negligible amount of the total cell
mass is suspended in the medium. The combination of the basket and
the recirculation also provides a bubble-free flow of oxygenated
medium through the fiber matrix. The fiber matrix is a non-woven
fabric having a "pore" diameter of from 10 .mu.m to 100 .mu.m,
providing for a high internal volume with pore volumes
corresponding to 1 to 20 times the volumes of individual cells.
[0609] The perfused packed-bed reactor offers several advantages.
With a fiber matrix carrier, the cells are protected against
mechanical stress from agitation and foaming. The free medium flow
through the basket provides the cells with optimum regulated levels
of oxygen, pH, and nutrients. Products can be continuously removed
from the culture and the harvested products are free of cells and
can be produced in low-protein medium, which facilitates subsequent
purification steps. This technology is explained in detail in WO
94/17178 (Aug. 4, 1994, Freedman et al.), which is hereby
incorporated by reference in its entirety.
[0610] The Cellcube.TM. (Corning-Costar) module provides a large
styrenic surface area for the immobilization and growth of
substrate attached cells. It is an integrally encapsulated sterile
single-use device that has a series of parallel culture plates
joined to create thin sealed laminar flow spaces between adjacent
plates.
[0611] The Cellcube.TM. module has inlet and outlet ports that are
diagonally opposite each other and help regulate the flow of media.
During the first few days of growth the culture is generally
satisfied by the media contained within the system after initial
seeding. The amount of time between the initial seeding and the
start of the media perfusion is dependent on the density of cells
in the seeding inoculum and the cell growth rate. The measurement
of nutrient concentration in the circulating media is a good
indicator of the status of the culture. When establishing a
procedure it may be necessary to monitor the nutrients composition
at a variety of different perfusion rates to determine the most
economical and productive operating parameters.
[0612] Other commercially available perfusion systems include, for
example, CellPerf.RTM. (Laboratories MABIO International,
Tourcoing, France) and the Stovall Flow Cell (Stovall Life Science,
Inc., Greensboro, N.C.)
[0613] The timing and parameters of the production phase of
cultures depends on the type and use of a particular cell line.
Many cultures require a different media for production than is
required for the growth phase of the culture. The transition from
one phase to the other will likely require multiple washing steps
in traditional cultures. However, one of the benefits of a
perfusion system is the ability to provide a gentle transition
between various operating phases. The perfusion system can also
facilitate the transition from a growth phase to a static phase
induced by an oxygen antagonist. Likewise, the perfusion system can
facilitate the transition from a static phase to a growth phase by
replacing the solution comprising an oxygen antagonist with, for
example, a physiological nutrient media.
[0614] G. Catheters
[0615] In certain embodiments, a catheter is used to provide an
active compound to an organism. Of particular interest is the
administration of such an agent to the heart or vasculature system.
Frequently, a catheter is used for this purpose. Yaffe et al., 2004
discusses catheters particularly in the context of suspended
animation, though the use of catheters were generally known prior
to this publication.
[0616] H. Delivery of Gases
[0617] 1. Respiration System
[0618] An exemplary gas delivery system 100 is illustrated in FIG.
9. The delivery system 100 is suited for delivering breathable
gases, including an active agent, to the respiration system of a
subject. The gas delivery system 100 includes one or more gas
sources 102. Each of the gas sources 102 is connected to a
regulator 104 and a flowmeter 106. The gas delivery system 100 also
includes an active agent source 107, an optional vaporizer 108, an
outlet controller 110, a scavenger 112, and an alarm/monitoring
system 114.
[0619] The delivery system 100 may include certain elements
generally used in an anesthesia delivery machine. For example,
anesthesia delivery machines generally include a high pressure
circuit, a low pressure circuit, a breathing circuit, and a
scavenging circuit. As described in FIGS. 10-11, one or more of the
gas sources 102, the vaporizer 108, the outlet controller 110, the
scavenger 112, and/or the alarm/monitoring system 114 may be
provided as part of a device having a high pressure, low pressure,
breathing, and/or scavenging circuit, and these elements may be
similar to those generally used in an anesthesia delivery machine.
Anesthesia delivery machines are described, for example, in U.S.
Pat. Nos. 4,034,753; 4,266,573; 4,442,856; and 5,568,910, the
contents of which are hereby incorporated by reference in their
entireties.
[0620] The gas sources 102 may be provided by tanks of compressed
gas; however, it should be understood that the gas sources 102 can
be either a gas or a liquid source that is converted to a gas. For
example, the vaporizer 108 can be used to vaporize a liquid gas
source. The regulators 104 include valves that reduce the pressure
of each of the gas sources 102. The decompressed gas then passes
through one of the flowmeters 106, which measures and controls the
flow of gas from each of the respective gas sources 102.
[0621] The gas sources 102 may be carrier gases that are used to
deliver the active agent 107. The carrier gases may be selected to
provide a desired environment for a subject to which the active
agent from the source 107 is delivered. For example, if the active
agent is delivered to a patient as a breathable gas, the carrier
gases can include oxygen, nitrous oxide, or air in sufficient
quantities to satisfy the needs of the patient. Other inert or
active gases may be used.
[0622] In some embodiments, one of the gas sources 102 includes the
active agent source 107. The active agent from the source 107 may
be a liquid gas source that is vaporized by the vaporizer 108 or
the active agent may be a gaseous source, such as a compressed gas
under high pressure. The active agent can be mixed with one or more
of the gas sources 102. The outlet controller 110 controls the
amount of the gas mixture that is provided to the subject.
[0623] The scavenger 112 is a device or system that scavenges
and/or ventilates the gases that are provided to the subject. For
example, if the active agent from the source 107 is provided as a
breathable gas to a patient, the scavenger 112 can be used to
remove the waste gases of the inhalant (such as the active agent),
unused oxygen, and exhaled carbon dioxide.
[0624] The alarm/monitoring system 114 includes sensors that
monitor the gas flow and/or gas content at one or more locations
within the delivery system 100. For example, the flow or amount of
oxygen may be monitored when the active agent from the source 107
is provided as a breathable gas to a patient to ensure that the
carrier gases include sufficient oxygen for the patient. The
alarm/monitoring system 114 also includes a user interface that is
configured to provide an audio or visual alarm or monitoring
information to a user of the delivery system 100, such as a visual
display, a light, or audio alarm. The alarm/monitoring system 114
can be configured to notify the user when a predetermined condition
is met and/or to provide information regarding gas levels.
[0625] With reference to FIG. 10, a system 100A includes a high
pressure circuit 116, a low pressure circuit 118, a breathing
circuit 120, and a scavenging circuit 122.
[0626] The high pressure circuit 116 includes the compressed gas
sources 102, which are connected to regulator valves 104b, 104a.
The regulator valves 104a control the amount of gas that flows from
each of the gas sources 102, and the regulator valves 104b may be
opened to increase the pressure of the gas, for example, by
providing an opening to the surrounding atmosphere.
[0627] The low pressure circuit 118 includes the flowmeters 106,
the active agent source 107, and the vaporizer 108. A gas mixture
from the gas sources 102 is provided by the flowmeters 106, which
control the amount of each of the gases from the gas sources 102.
As illustrated in FIG. 10, the active agent source 107 is a liquid.
The active agent source 107 is vaporized by the vaporizer 108 and
added to the gas mixture.
[0628] The breathing circuit 120 includes the outlet controller
110, two one-way valves 124, 126 and an absorber 128. The scavenger
circuit 122 includes a valve 112a, a reservoir 112b, and an outlet
112c. A subject 130 receives the gas mixture from the outlet
controller 110 and the resulting gas is ventilated by the scavenger
circuit 122. More specifically, the outlet controller 110 controls
the amount of the gas mixture that is delivered to the subject 130
via the one-way valve 124. Expired gases flow through the one-way
valve 126 to the valve 112a and to the reservoir 112b. Excess gases
exit through the outlet 112c of the scavenger 112. Some of the
gases may be recycled and flow through the absorber 128 and into
the breathing circuit 120. The absorber 128 may be a carbon dioxide
absorbing canister for reducing carbon dioxide gases from exhaled
gases. In this configuration, expired oxygen and/or active agent
may be re-circulated and reused.
[0629] One or more sensors S may be added at various positions in
the system 100A. The sensors S sense and/or monitor the gases in
the system 100A. For example, if one of the gas sources 102 is
oxygen, one of the sensors S may be an oxygen sensor configured and
positioned to monitor the oxygen in the system 100A so that the
patient receives a suitable amount of oxygen. The sensors S are in
communication with the alarm/monitoring system 114 (see FIG. 9). If
undesirable or dangerous gas levels are present in the system 100,
the alarm/monitoring system 114 may alert a user of the system 100A
so that appropriate action may be taken, such as increasing the
oxygen levels given to the subject 130 or disconnecting the subject
130 from the delivery system 100A.
[0630] With reference to FIG. 11, a system 100B is shown in which
the active agent source 107 is connected to two of the regulator
valves 104b, 104a. If the active agent source 107 is a liquid gas
source, an optional vaporizer 108 is provided to vaporize the
liquid gas source. If the active agent source 107 is gaseous (e.g.,
a high pressure gas), then the vaporizer 108 may be omitted. The
active agent from the source 107 is mixed with the other gas
sources 102 in the low pressure circuit 118 in amounts that are
controlled by the flowmeters 106. The low pressure circuit 118
includes a gas reservoir 109 that contains any overflow of the gas
mixture as it flows to the breathing circuit 120. It should be
understood that the active agent source 107 and/or any of the gas
sources 102 may be provided as a liquid gas source with a
vaporizer. The elements of the system 100B illustrated in FIG. 11
are essentially the same as those described above with respect to
FIG. 10 and will not be described further.
[0631] Methods according to embodiments of the present invention
which may be carried out using the systems 100, 100A, 100B are
illustrated in FIG. 12. A mixture of one or more breathable gas
sources is provided (Block 202). The breathable gas sources may be
obtained from the gas sources 102 as described with respect to
FIGS. 9-11. A predetermined amount of the active agent is added to
the gas mixture (Block 204), such as is shown with respect to the
active agent source 107 in FIGS. 9-11. The gas mixture is
administered to the subject 120 (Block 306). Exhaled gases are
ventilated and/or recycled (Block 208), for example, by the
scavenger 112. Although the methods of FIG. 12 are described with
respect to the systems 100, 100A, 100B of FIG. 9-11, it should be
understood that any suitable system or device may be used to carry
out the steps in FIG. 12.
[0632] 2. Reduced Pressure Delivery System
[0633] Embodiments of a gas delivery system 300 are illustrated
with respect to FIG. 13. The gas delivery system 300 is positioned
on a subject 302. The gas delivery system 300 is particularly
suited to deliver an active agent in a gas mixture to the tissue of
a subject 302, for example, wound tissue.
[0634] The system 300 includes a reduced pressure chamber 304
having a screen 306 that covers the treatment area of the subject
302. The reduced pressure chamber 304 is connected to a vacuum pump
310 by a pump outlet 310a. The reduced pressure chamber 304
includes an inlet 308a and an outlet 308b, which are in turn
connected to an active agent source 307. A controller 320 is
connected to the active agent source 307 and the vacuum pump 310.
Reduced pressure chambers and vacuum pump systems are discussed in
U.S. Pat. Nos. 5,645,081 and 5,636,643, the contents of which are
hereby incorporated by reference in their entireties.
[0635] The reduced pressure chamber 304 is configured to enclose an
area of the subject 302 to provide a fluid-tight or gas-tight
enclosure to effect treatment of the area with reduced or negative
pressure and the active agent source 307. The pressure chamber 304
can be affixed to the subject 302 with a cover (not shown), such as
a flexible, adhesive, fluid impermeable polymer sheet. The cover
can have an adhesive backing that functions to cover the skin
around the periphery of the area being treated and to provide a
generally gas-tight or fluid-tight seal and to hold the chamber 304
in position.
[0636] The screen 306 is positioned over the treatment area of the
subject 302. For example, if the treatment area of the subject 302
includes a wound, the screen 306 can be positioned over the wound
to prevent its overgrowth. The size and configuration of the screen
306 can be adjusted to fit the individual treatment area, and may
be formed from a variety of porous materials. The material should
be sufficiently porous to allow oxygen any other gases, such as
gases from the active agent source 307, to reach the treatment
area. For example, the screen 306 can be in the form of an
open-cell polymer foam, such as a polyurethane foam, which is
sufficiently porous to allow gas flow to and/or from the treatment
area. Foams may be used that vary in thickness and rigidity,
although it may be desirable to use a spongy material for the
patient's comfort if the patient must lie upon the appliance during
treatment. The foam may also be perforated to enhance gas flow and
to reduce the weight of the system 300. The screen 306 may be cut
to an appropriate shape and size to fit within the treatment area,
or alternatively, the screen 306 may be sufficiently large to
overlap the surrounding skin.
[0637] The vacuum pump 310 provides a source of suction within the
reduced pressure chamber 304. The active agent source 307 provides
an amount of the active agent to the reduced pressure chamber 304.
The controller 320 controls the amount of vacuum applied to the
reduced pressure chamber 304 by the vacuum pump 310 and the amount
of the active agent that is supplied to the chamber 304 by the
active agent source 307.
[0638] It should be understood that the controller 320 can apply a
vacuum and/or the active agent in a substantially constant manner,
cyclically, or using various fluctuations or patterns or any
combination thereof. In some embodiments, the active agent is
supplied by the active agent source 307 alternatively with the
vacuum pumping action of the vacuum pump 310. That is, the
controller 320 alternatively activates the vacuum pump 310 while
deactivating the active agent source 307 and then activates the
active agent source 307 while deactivating the vacuum pump 310. The
pressure in the reduced pressure chamber 304 is allowed to
fluctuate. In other embodiments, a substantially constant pressure
is maintained by the vacuum pump 310 and the active agent source
307 provides a substantially constant amount of active agent to the
chamber 304 in the reduced pressure environment. In some
embodiments, a substantially constant pressure is maintained by the
vacuum pump 310 and the amount of the active agent varies in a
cyclical manner. In other embodiments, the pressure in the reduced
pressure chamber 304 is made to fluctuate by the vacuum pump 310,
and the amount of active agent supplied by the source 307 also
fluctuates. The fluctuations of either the vacuum pump 310 and the
resulting pressure in the chamber 304 or the amount of active agent
supplied by the source 307 may be cyclical or not cyclical.
[0639] Methods according to embodiments of the present invention
that may be carried out using the system 300 are illustrated in
FIG. 14. The chamber 304 is positioned over the treatment area of
the subject 302 (Block 402). Pressure is reduced in the chamber 304
by the vacuum pump 310 (Block 404). A predetermined amount of
active agent from the active agent source 307 is applied to the
chamber (Block 406). Although the methods of FIG. 14 are described
with respect to the system 300 of FIG. 12, it should be understood
that any suitable system or device may be used to carry out the
steps in FIG. 14. For example, the outlet 308b may be omitted and
the active agent may be supplied to the chamber 304 by the single
inlet 308a. Other gases may also be added to the chamber 304, for
example, using a single inlet or an inlet and an outlet, such as is
illustrated with respect to the active agent source 307 and the
inlet 308a and the outlet 308b. In some embodiments, the vacuum
pump 310 is attached to an additional collection container between
the pump 310 and the chamber 304 for collecting exudates from the
treatment area, for example, as described in U.S. Pat. No.
5,636,643.
[0640] In some embodiments, the negative pressure gas delivery
system 500, as depicted in FIG. 22A, comprises an active oxygen
antagonist source in a container 502, connected to a drape 504, via
an inlet 506, by a conduit 508. The drape forms a sealed envelope
against a tissue site 510, which may a wound site. In some
embodiments, the drape has an outlet 512 in communication with a
negative pressure source 514, via a conduit 516. In some
embodiments a waste canister 518, which may be a removable waste
canister, is in communication between the outlet and the negative
pressure source. In some embodiments, a return outlet 520 is
connection with the container 502 via a conduit 522. In some
embodiments, as shown in FIG. 22B, a vaporizer 524 is interposed in
the communication between the container 502 and the drape 504.
[0641] The conduits may be flexible and may suitably be plastic of
a like material hose. The negative pressure source 514, which may
suitably be a vacuum pump, is in some embodiments in fluid
communication with the outlet 512 via the conduit 516, for the
promotion of fluid drainage, as is known in the art. In some
embodiments, the waste canister 518 is placed under vacuum through
fluid communication to collect drainage fluid. Preferably a filter
(not shown), which may be a hydrophobic membrane filter, is
interposed between the canister the negative pressure source to
protect against contamination from drainage fluids sucked into the
canister. In some embodiments, the drape 504 comprises an
elastomeric material, which may therefore accommodate pressure
changes over the tissue site area during intermittent operation of
the negative pressure source. In some embodiments, the periphery of
the drape is covered with a pressure sensitive adhesive, which may
be acrylic adhesive, for sealing the drape over the tissue
site.
[0642] Negative pressure gas delivery systems 300 and 500 as
illustrated in FIG. 12 and FIG. 22A-B are useful for treating a
variety of areas for treatment, and, in particular, for treating
wounds. Wounds that may be treated using the system 300 include
infected open wounds, decubitus ulcers, dehisced incisions, partial
thickness burns, and various lesions to which flaps or grafts have
been attached. Treatment of a wound can be carried out by securing
a gas delivery system to the treatment site as previously shown and
described, maintaining a substantially continuous or cyclical
reduced pressure within the reduced pressure chamber 304 and
supplying the active agent to the chamber 304 in a substantially
continuous or cyclical fashion until the wound has reached a
desired improved condition. A selected state of improved condition
may include formation of granulation tissue sufficient for the
attachment of a flap or graft, reduction of microbial infection in
the wound, arrest or reversal of burn penetration, closure of the
wound, integration of a flap or graft with the underlying wounded
tissue, complete healing of the wound, or other stages of
improvement or healing appropriate to a given type of wound or
wound complex. The gas delivery system may be changed periodically,
such as at 48 hrs intervals, during treatment, particularly when
using a gas delivery system incorporating a screen on or in the
wound. The method may be practiced using a negative or reduced
pressure ranging from 0.01 to 0.99 atmospheres, or the method may
be practiced using a negative or reduced pressure ranging between
0.5 to 0.8 atmospheres. The time period for use of the method on a
wound may be at least 12 hrs, but can be, for example, extended for
one or more days. There is no upper limit beyond which use of the
method is no longer beneficial; the method can increase the rate of
closure up to the time the wound actually closes. Satisfactory
treatment of various types of wounds may be obtained via the use of
reduced pressures equivalent to about 2 to 7 in. Hg below
atmospheric pressure.
[0643] Supplying reduced pressure to the gas delivery system in an
intermittent or cyclic manner, such as described above, may be
useful for treating wounds in the presence of the active agent.
Intermittent or cyclic supply of reduced pressure to a gas delivery
system may be achieved by manual or automatic control of the vacuum
system. A cycle ratio, the ratio of "on" time to "off" time, in
such an intermittent reduced pressure treatment may be as low as
1:10 or as high as 10:1. A typical ratio is approximately 1:1 which
is usually accomplished in alternating 5 minute intervals of
reduced pressure supply and non-supply.
[0644] A suitable vacuum system includes any suction pump capable
of providing at least 0.1 pounds of suction to the wound, or up to
three pounds suction, or up to fourteen (14) pounds suction. The
pump can be any ordinary suction pump suitable for medical purposes
that is capable of providing the necessary suction. The dimension
of the tubing interconnecting the pump and the reduced pressure
appliance is controlled by the pump's ability to provide the
suction level needed for operation. A 1/4 inch diameter tube may be
suitable.
[0645] Embodiments of the present invention also include methods of
treating damaged tissue, which include the steps of applying
negative pressure to a wound and the active agent for a selected
time and at a selected magnitude sufficient to reduce bacterial
density in the wound. Open wounds are almost always contaminated
with harmful bacteria. Generally a bacterial density of 10.sup.5
bacterial organisms per gram of tissue is regarded as infected. It
is generally accepted that at this level of infection, grafted
tissue will not adhere to a wound. These bacteria must be killed,
either through the wound host's natural immune response or through
some external method, before a wound will close. The application of
negative pressure and active agent to a wound may reduce the
bacterial density of the wound. It is believed that this effect may
be due to the bacteria's incompatibility with a negative pressure
environment or the increased blood flow to the wound area in
combination with exposure to the active agent, as blood brings with
it cells and enzymes to destroy the bacteria. Methods according to
embodiments of the present invention can be used to reduce
bacterial density in a wound by at least half. In some embodiments,
it can be used to reduce bacterial density by at least 1.000-fold
or by at least 1,000,000-fold.
[0646] Embodiments of the present invention also include methods of
treating a burn which include the steps of applying negative
pressure and the active agent to the burn over an area with
predetermined reduced pressure and for a time sufficient to inhibit
formation of a full thickness burn. A partial thickness burn, one
which has a surface layer of dead tissue and an underlying zone of
stasis, is often sufficiently infected so that it will transform
within 24-48 hrs into a full thickness burn, one in which all
epidermal structures are destroyed. The application of negative
pressure and an amount of the active agent to the wound may prevent
the infection from becoming sufficiently severe to cause
destruction of the underlying epidermal structures. The magnitude,
pattern, and duration of pressure application can vary with the
individual wound.
[0647] Embodiments of the present invention also include methods
for enhancing the attachment of living tissue to a wound which
comprises the steps of first joining the living tissue to the wound
to form a wound-tissue complex, then applying a negative or reduced
pressure of selected magnitude and an amount of the active agent to
the wound-tissue complex over an area sufficient to promote
migration of epithelia and subcutaneous tissue toward the complex,
with the negative pressure and exposure to the active agent being
maintained for a selected time period sufficient to facilitate
closure of the wound. Attachment of living tissue to a wound is a
common procedure that can take many forms. For example, one common
technique is the use of a "flap," a technique in which skin tissue
from an area adjacent to the wound is detached on three sides but
remains attached on the fourth, then is moved onto the wound.
Another frequently used technique is an open skin graft in which
skin is fully detached from another skin surface and grafted onto
the wound. The application of negative pressure and active agent to
the wound-graft complex reduces bacterial density in the complex
and improves blood flow to the wound, thereby improving the
attachment of the grafted tissue.
[0648] I. Other Apparatuses
[0649] Within certain embodiments of the invention, it may be
desirable to supplement the methods of the present invention for
the treatment of patients who will be or have been subjected to
trauma with the ability to externally manipulate the core body
temperature of the patient. In this regard, the core body
temperature of a patient may be, in combination with the methods of
the present invention, manipulated by invasive or non-invasive
routes. Invasive methods for the manipulation of core body
temperature include, for example, the use of a heart-lung pump to
heat or cool the patient's blood thus raising or cooling the
patient's core body temperature. Non-invasive routes to manipulate
core body temperature include systems and apparatuses that transfer
heat into or out of the patient's body.
[0650] J. Further Delivery Devices or Apparatuses
[0651] In some embodiments it is contemplated that methods or
compositions will involve a specific delivery device or apparatus.
Any method discussed herein can be implemented with any device for
delivery or administration including, but not limited, to those
discussed herein.
[0652] For topical administration of active compounds of the
invention may be formulated as solutions, gels, ointments, creams,
suspensions, etc. as are well-known in the art. Systemic
formulations may include those designed for administration by
injection or infusion, e.g., subcutaneous, intravenous,
intramuscular, intrathecal or intraperitoneal injection, as well as
those designed for transdermal, transmucosal, oral or pulmonary
administration.
[0653] For oral administration, the active compounds of the
invention to be formulated as tablets, pills, dragees, capsules,
liquids, gels, syrups, slurries, suspensions and the like, for oral
ingestion by a patient to be treated or oral liquid preparations
such as, for example, suspensions, elixirs and solutions.
[0654] For buccal administration, the compositions may take the
form of tablets, lozenges, etc. formulated in conventional manner.
Other intramucosal delivery might be by suppository or
intranasally.
[0655] For administration directly to the lung by inhalation the
compound of invention may be conveniently delivered to the lung by
a number of different devices. For example,
[0656] Metered-Dose Inhalers (MDIs): a Metered Dose Inhaler ("MDI")
which utilizes canisters that contain a suitable low boiling
propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane,
dichlorotetrafluoroethane, carbon dioxide or other suitable gas may
be used to deliver the compound of invention directly to the lung.
MDI devices are available from a number of suppliers such as 3M
Corporation (e.g., on the world wide web at
3m.com/us/healthcare/manufacturers/dds/pdf/idd_valve_canister_brochure.pd-
f-), Nasacort from Aventis (e.g., world wide web at
products.sanofi-aventis.us/Nasacort_HFA/nasacort_HFA.html-63k-),
Boehringer Ingelheim, (e.g., world wide web
at.boehringer-ingelheim.com/corporate/home/download/r_and
d2003.pdf) Aerobid from Forest Laboratories, (e.g., world wide web
at.frx.com/products/aerobid.aspx) Glaxo-Wellcome, (for example, on
the world wide web at .gsk.com/research/newmedicines/newmedicines
harma.html) and Schering Plough, (world wide web at
.schering-plough.com/schering_lough/pc/allergy_respiratory.jsp).
[0657] Dry Powder Inhalers (DPIs): DPI devices typically use a
mechanism such as a burst of gas to create a cloud of dry powder
inside a container, which may then be inhaled by the patient. DPI
devices are also well known in the art and may be purchased from a
number of vendors which include, for example, Foradil aerolizer
from Schering Corporation, (e.g., world wide web
.spfiles.com/piforadil.pdf) Advair Diskus from Glaxo-Wellcome.
(e.g., world wide web at us.gsk.com/products/assets/us_advair.pdf-)
A popular variation is the multiple dose DPI ("MDDPI") system,
which allows for the delivery of more than one therapeutic dose.
MDDPI devices are available from companies such as Plumicort
Turbuhaler from AstraZeneca, (e.g., world wide web
at.twistclickinhale.com/GlaxoWellcome, (e.g., world wide web at
us.gsk.com/products/assets/us_advair.pdf-) and Schering Plough,
(e.g., world wide web at .schering-plough.com/schering
plough/pc/allergy_respiratory.jsp). It is further contemplated that
such devices, or any other devices discussed herein, may be altered
for single use.
[0658] Electrohydrodynamic (EHD) aerosol delivery: EHD aerosol
devices use electrical energy to aerosolize liquid drug solutions
or suspensions (see e.g., Noakes et al., U.S. Pat. No. 4,765,539;
Coffee, U.S. Pat. No. 4,962,885; Coffee, PCT Application, WO
94/12285; Coffee, PCT Application, WO 94/14543; Coffee, PCT
Application, WO 95/26234, Coffee, PCT Application, WO 95/26235,
Coffee, PCT Application, WO 95/32807. EHD aerosol devices may more
efficiently deliver drugs to the lung than existing pulmonary
delivery technologies.
[0659] Nebulizers: Nebulizers create aerosols from liquid drug
formulations by using, for example, ultrasonic energy to form fine
particles that may be readily inhaled Examples of nebulizers
include devices supplied by Sheffield/Systemic Pulmonary Delivery
Ltd. (See, Armer et al., U.S. Pat. No. 5,954,047; van der Linden et
al., U.S. Pat. No. 5,950,619; van der Linden et al., U.S. Pat. No.
5,970,974), Intal nebulizer solution by Aventis, (e.g., world wide
web at
.fda.gov/medwatch/SAFETY/2004/feb_PI/Intal_Nebulizer_PI.pdf).
[0660] For administration of a gas directly to the lungs by
inhalation various delivery methods currently available in the
market for delivering oxygen may be used. For example, a
resuscitator such as an ambu-bag may be employed (see U.S. Pat.
Nos. 5,988,162 and 4,790,327). An ambu-bag consists of a flexible
squeeze bag attached to a face mask, which is used by the physician
to introduce air/gas into the casualty's lungs.
[0661] A portable, handheld medicine delivery device capable
producing atomized agents that are adapted to be inhaled through a
nebulizer by a patient suffering from a respiratory condition. In
addition, such delivery device provides a means wherein the dose of
the inhaled agent can be remotely monitored and, if required
altered, by a physician or doctor. See U.S. Pat. No. 7,013,894.
Delivery of the compound of invention may be accomplished by a
method for the delivery of supplemental gas to a person combined
with the monitoring of the ventilation of the person with both
being accomplished without the use of a sealed face mask such as
described in U.S. Pat. No. 6,938,619. A pneumatic oxygen conserving
device for efficiently dispensing oxygen or other gas used during
respiratory therapy such that only the first part of the patient's
breath contains the oxygen or other therapeutic gas. (See U.S. Pat.
No. 6,484,721). A gas delivery device is used which is triggered
when the patient begins to inhale. A tail of gas flow is delivered
to the patient after the initial inhalation timed period to prevent
pulsing of gas delivery to the patient. In this manner gas is only
delivered to the patient during the first portion of inhalation
preventing gas from being delivered which will only fill the air
passageways to the patient's lungs. By efficiently using the
oxygen, cylinder bottles of oxygen used when a patient is mobile
will last longer and be smaller and easier to transport. By
pneumatically delivering the gas to the patient no batteries or
electronics are used.
[0662] All the devices described here may have an exhaust system to
bind or neutralize the compound of invention.
[0663] Transdermal administration of the compound of the invention
can be achieved by medicated device or patch which is affixed to
the skin of a patient. The patch allows a medicinal compound
contained within the patch to be absorbed through the skin layers
and into the patient's blood stream. Such patches are commercially
available as Nicoderm CQ patch from Glaxo Smithkline, (world wide
web at nicodermcq.com/NicodermCQ.aspx) and as Ortho Evra from
Ortho-McNeil Pharmaceuticals, (world wide web
at.ortho-mcneilpharmaceutical.com/healthinfo/womenshealth/products/orthoe-
vra.html). Transdermal drug delivery reduces the pain associated
with drug injections and intravenous drug administration, as well
as the risk of infection associated with these techniques.
Transdermal drug delivery also avoids gastrointestinal metabolism
of administered drugs, reduces the elimination of drugs by the
liver, and provides a sustained release of the administered drug.
Transdermal drug delivery also enhances patient compliance with a
drug regimen because of the relative ease of administration and the
sustained release of the drug.
[0664] Other modifications of the patch include the Ultrasonic
patch which is designed with materials to enable the transmission
of ultrasound through the patch, effecting the delivery of
medications stored within the patch, and to be used in conjunction
with ultrasonic drug delivery processes (see U.S. Pat. No.
6,908,448). Patch in a bottle (U.S. Pat. No. 6,958,154) includes a
fluid composition, e.g., an aerosol spray in some embodiments, that
is applied onto a surface as a fluid, but subsequently dries to
form a covering element, such as a patch, on a surface of a host.
The covering element so formed has a tack free outer surface
covering and an underlying tacky surface that helps adhere the
patch to the substrate.
[0665] Another drug delivery system comprises one or more ball
semiconductor aggregations and facilitating release of a drug
stored in a reservoir. The first aggregate is used for sensing and
memory, and a second aggregation for control aspects, such as for
pumping and dispensing of the drug. The system may communicate with
a remote control system, or operate independently on local power
over a long period for delivery of the drug based upon a request of
the patient, timed-release under control by the system, or delivery
in accordance with measured markers. See U.S. Pat. No.
6,464,687.
[0666] PUMPS and Infusion Devices: An infusion pump or perfusor
infuses fluids, medication or nutrients into a patient's
circulatory system. Infusion pumps can administer fluids in very
reliable and inexpensive ways. For example, they can administer as
little as 0.1 mL per hour injections (too small for a drip),
injections every minute, injections with repeated boluses requested
by the patient, up to maximum number per hour (e.g. in
patient-controlled analgesia), or fluids whose volumes vary by the
time of day. Various types of infusion devices have been described
in the following patent applications before the United States
Patent and Trademark Office. These include but are not limited to
U.S. Pat. No. 7,029,455 U.S. Pat. No. 6,805,693, U.S. Pat. No.
6,800,096, U.S. Pat. No. 6,764,472, U.S. Pat. No. 6,742,992, U.S.
Pat. No. 6,589,229, U.S. Pat. No. 6,626,329, U.S. Pat. No.
6,355,019, U.S. Pat. No. 6,328,712, U.S. Pat. No. 6,213,738, U.S.
Pat. No. 6,213,723, U.S. Pat. No. 6,195,887, U.S. Pat. No.
6,123,524 and U.S. Pat. No. 7,022,107. In addition, infusion pumps
are also available from Baxter International Inc. (world wide web
at .baxter.com/products/medication-management/infusion_pumps/),
Alaris Medical Systems (world wide web at
alarismed.com/products/infusion.shtml) and from B Braun Medical
Inc. (world wide web at
bbraunusa.com/index.cfm?uuid=001AA837D0B759A1E34666434FF604ED).
[0667] Oxygen/Gas bolus delivery device: Such a device for
delivering gas to Chronic Obstructive Pulmonary Disease (COPD)
patients is a available from Tyco Healthcare (world wide web at.
tycohealth-ece.com/files/d0004/ty_zt7ph2.pdf). It can also be used
to deliver the compound of invention. The above device is
cost-effective, lightweight, inconspicuous and portable.
[0668] "Patch in a bottle" (U.S. Pat. No. 6,958,154) includes a
fluid composition, e.g., an aerosol spray in some embodiments, that
is applied onto a surface as a fluid, but subsequently dries to
form a covering element, such as a patch, on a surface of a host.
The covering element so formed has a tack free outer surface
covering and an underlying tacky surface that helps adhere the
patch to the substrate.
[0669] Implantable Drug Delivery System: Another drug delivery
system comprises one or more ball semiconductor aggregations and
facilitating release of a drug stored in a reservoir. The first
aggregate is used for sensing and memory, and a second aggregation
for control aspects, such as for pumping and dispensing of the
drug. The system may communicate with a remote control system, or
operate independently on local power over a long period for
delivery of the drug based upon a request of the patient,
timed-release under control by the system, or delivery in
accordance with measured markers. See U.S. Pat. No. 6,464,687.
[0670] The contents of each of the cited patents and web addresses
discussed in this section are hereby incorporated by reference.
VIII. Combination Therapies
[0671] The compounds and methods of the present invention may be
used in the context of a number of therapeutic and diagnostic
applications. In order to increase the effectiveness of a treatment
with the compositions of the present invention, such as oxygen
antagonists or other active compounds, it may be desirable to
combine these compositions with other agents effective in the
treatment of those diseases and conditions (secondary therapy). For
example, the treatment of stroke (antistroke treatment) typically
involves an antiplatelet (aspirin, clopidogrel, dipyridamole,
ticlopidine), an anticoagulant (heparin, warfarin), or a
thrombolytic (tissue plasminogen activator).
[0672] Various combinations may be employed; for example, anactive
compound, such as H.sub.2S, is "A" and the secondary therapy is
"B":
TABLE-US-00003 A/B/A B/A/B B/B/A A/A/B A/B/B B/A/A A/B/B/B B/A/B/B
B/B/B/A B/B/A/B A/A/B/B A/B/A/B A/B/B/A B/B/A/A B/A/B/A B/A/A/B
A/A/A/B B/A/A/A A/B/A/A A/A/B/A
[0673] Administration of the oxygen antagonists and/or other active
compounds of the present invention to biological matter will follow
general protocols for the administration of that particular
secondary therapy, taking into account the toxicity, if any, of the
oxygen antagonist (or other active compound) treatment. It is
expected that the treatment cycles would be repeated as necessary.
It also is contemplated that various standard therapies, as well as
surgical intervention, may be applied in combination with the
described therapies.
IX. EXAMPLES
[0674] The following examples are included to demonstrate preferred
embodiments of the invention. It should be appreciated by those of
skill in the art that the techniques disclosed in the examples
which follow represent techniques discovered by the inventor to
function well in the practice of the invention, and thus can be
considered to constitute preferred modes for its practice. However,
those of skill in the art should, in light of the present
disclosure, appreciate that many changes can be made in the
specific embodiments which are disclosed and still obtain a like or
similar result without departing from the spirit and scope of the
invention.
Example 1
Preservation of Nematodes in Carbon Monoxide
[0675] The atmosphere contains 210,000 ppm oxygen. Exposure to low
levels of oxygen, or hypoxia, results in cellular damage and death
in humans. In the nematode, C. elegans, oxygen concentrations
between 100 ppm and 1000 ppm are also lethal. By critically
studying the response of nematodes to a range of oxygen tensions,
it was found that oxygen concentrations below 10 ppm and above 5000
ppm are not lethal. In 10 ppm oxygen balanced with nitrogen,
nematodes enter into a state of reversible suspended animation in
which all aspects of animation observable under the light
microscope ceases (Padilla et al., 2002). In oxygen concentrations
of 5000 ppm (balanced with nitrogen) and above, nematodes progress
through their life cycle normally. In a search for drugs that
protect nematodes against hypoxic damage, carbon monoxide was
tested.
[0676] To achieve specific atmospheric conditions the following
apparatus was used: a glass syringe barrel having a tip with a
locking device such as a LUER-LOK with the large opening of the
barrel sealed with a custom-machined steel and rubber fitting to
make an airtight seal was locked to via locking device to the inlet
port of an environmental chamber having an inlet and an outlet port
each fitted with a locking devices such as a LUER-LOK fitting. A
defined gas was humidified and provided to the environmental
chamber by first venting the gas from a compressed tank (Byrne
Specialty Gas, Seattle, Wash.) through a gas washing bottle (500 ml
Kimex) filled with double distilled water. The gas washing bottle
was connected to the environmental chamber past a gas-flow meter. A
gas flow meter was used to provide a regulated 70 cc/min flow
through the environmental chamber throughout the 24 hr
incubation.
[0677] To test whether induced, reversible stasis could be achieved
in C. elegans nematodes, 2-cell C. elegans embryos, L3 larvae or
adult nematodes were collected and exposed to either an environment
of effectively 100% CO, an environment of 100% N.sub.2, an
environment comprising 500 ppm oxygen balanced with carbon
monoxide, or to environments comprising 100, 500 or 1000 ppm oxygen
balanced with nitrogen at room temperature. Nematodes were
visualized using differential interference contrast microscopy
(also known as Nomarski optics). Images were collected and analyzed
using NIH image and Adobe Photoshop 5.5. Embryos are approximately
50 .mu.m in length.
[0678] Results of these experiments showed that 100% carbon
monoxide was not lethal and induced reversible suspended animation.
Nematodes did not survive 500 ppm oxygen balances with nitrogen,
however, those treated with 500 ppm oxygen balanced with carbon
monoxide entered into suspended animation and survived. See
below:
Example 2
Preservation of Human Skin in Carbon Monoxide
[0679] Carbon monoxide is extraordinarily toxic to humans because
it strongly competes with oxygen for binding to hemoglobin, the
primary molecule that distributes oxygen to tissues. The fact that
nematodes, which do not have hemoglobin, are resistant to carbon
monoxide and even protected against hypoxic damage by this drug
suggested the possibility that carbon monoxide would protect
against hypoxic damage in human tissue in situations where blood is
not present, such as in tissue transplant or blood free surgical
fields. To tested this hypothesis using human skin.
[0680] Three human foreskins were obtained for this purpose. The
foreskin tissue was preserved in keratinocyte growth medium (KGM)
containing insulin, EGF (0.1 ng/ml), hydrocortisone (0.5 mg/ml) and
bovine pituitary extract (approx. 50 micrograms/ml of protein).
Foreskins were rinsed in PBS, and excess fatty tissue was removed.
Each foreskin sample was divided into 2 equal pieces. Each piece
was placed into a separate container containing a solution of PBS
with 24 mg/ml of Dispase II (from Bacillus Polymyxa EC
3.4.24.4:Roche Diagnostics Corp., Indianapolis, Ind.). One
container (containing a foreskin piece in PBS with Dispase II) was
kept in a humid chamber in a fume hood. The other container (with
the other half of the foreskin in PBS with Dispase II) was placed
in the same fume hood in an environmental chamber perfused with
humidified 100% CO. Both samples were maintained at room
temperature for 24 hrs. Methods used to establish defined
atmospheric conditions were identical to those used in Example
1.
[0681] Following the 24 hr exposure to normoxia or 100% CO,
keratinocytes were isolated from the foreskins according to the
method described by Boyce et al. (1983; 1985; each of which is
incorporated herein by reference in its entirety). Briefly, the
epidermis from each foreskin sample was removed to a fresh dish
containing PBS. The epidermis was minced and homogenized prior to
incubation in 3 ml of 0.05% Trypsin, 1 mM EDTA for 5 minutes, at
room temperature, to separate basal cells from the epidermis. After
incubation, 6 ml of 400 .mu.g/ml (micrograms per ml) Soybean
Trypsin Inhibitor, 1 mg/ml BSA was added and the samples were
centrifuged at 900 RPM. The supernatant from each sample was
discarded and the sample pellets were resuspended in 10 ml of KGM.
Each sample was split into two 10 cm plates each of which contained
5 ml KGM and 100 .mu.l of HEPES pH 7.3
(N-2-hydroxyethylpiperazine-N'-2-ethane sulfonic acid). The plates
were incubated in a 37.degree. C. incubator perfused with 95% room
air, 5% carbon dioxide for five days.
[0682] Cells were inspected visually using an inverted phase
contrast microscope. All three of the keratinocyte populations
exposed to normoxia showed little or no growth. All three of the
keratinocyte populations exposed to 100% CO showed significant
growth. Quantitation of the number of viable keratinocytes as
judged by colony formation was quantified for two of the three
foreskins. See FIG. 1.
TABLE-US-00004 TABLE 1 Quantitation of Colony Formation Foreskin
Atmosphere Total colonies 1 100% 542 colonies (many of which were
very CO large) 1 Normoxia 2 colonies (both small) 2 100% CO 780
colonies (many of which were very large) 2 Normoxia 0 colonies
Example 3
Further Preservation Experiments with Nematodes
[0683] The following example contains information that overlaps and
extends the information disclosed in Example 1.
A. Materials and Methods
[0684] Environmental chambers and apparati. Oxygen deprivation
experiments were carried out using a custom atmospheric chamber
designed by W. Van Voorhies (Van Voorhies et al., 2000). The
chamber is a 30 mL glass syringe (Fisher #14-825-10B) fitted with a
custom steel stopper that is lined with two viton O-rings to ensure
a tight seal. The stopper is bored through and has a steel lure
lock on the exterior face so that a hose carrying compressed gas
can be attached. A defined gas mixture is delivered to the chamber
at a constant pressure and flow rate from compressed tanks by
passing first through a rotometer (Aalborg, flow-tube number
032-41ST) or mass flow controller (Sierra Instruments #810) to
monitor flow rate and then through a 500 ml gas washing bottle
(Fisher #K28220-5001) containing 250 ml water to hydrate the gas.
1/4'' OD nylon (Cole-Parmer #P-06489-06) or FEP (Cole-Parmer
#A-06450-05) tubing was used and connections between tubing and the
regulators and between the tubing and the rotometers were made with
brass John-Guest-type fittings (Byrne Gas). All other connections
were made with either microflow quick-connect fittings (Cole-Parmer
#A-06363-57, #A-06363-52) or standard lure fittings (Cole-Parmer
#A-06359-37, #A-06359-17).
[0685] Viability of nematodes in hypoxia. Bristol strain N2 were
continuously maintained at 20.degree. C. with care taken to ensure
the population did not starve. Log-phase, adult C. elegans were
picked into a drop of sterile water containing 100 .mu.g/ml
ampicillin, 15 .mu.g/ml tetracycline and 200 .mu.g/ml streptomycin
on a glass plate. Adults were chopped with a razor blade and 2-cell
embryos were picked using a mouth pipet. 30-60 2-cell embryos were
transferred to a small glass boat (custom made to fit atmospheric
chambers, Avalon Glass Works, Seattle Wash.) filled with 3 ml of 1%
agarose in M9. Boats were then placed into a humid chamber for 2
hours to allow the embryos to age and then placed into the
environmental chamber. The environmental chambers were continuously
perfused at room temperature with either pure N.sub.2 (grade 4.5),
100 ppm O.sub.2/N.sub.2, 500 ppm O.sub.2/N.sub.2, 1000 ppm
O.sub.2/N.sub.2, or 5000 ppm O.sub.2/N.sub.2 at 70 cc/min for 24
hrs. Following exposure, agarose chunks containing the embryos were
cut out of the boat and placed with embryos facing up onto a
medium-sized NGM plate seeded with E. coli (OP50). Embryos were
scored for hatching 24 hours after exposure and hatched L1's were
transferred to the surface of the NGM plate and followed to
adulthood. Animals that could not be accounted for were dropped
from the total. All gases were supplied by Byrne Gas (Seattle,
Wash.). The pure N.sub.2 was guaranteed to contain less than 10 ppm
impurities and all O.sub.2/N.sub.2 mixtures were certified to
.+-.2% of the oxygen content (e.g., 100 ppm O.sub.2/N.sub.2 was
certified to contain between 98 ppm O.sub.2 and 102 ppm O.sub.2).
Parts per million to kPa conversion was based on 1 million
parts=101 kPa at 1 atmosphere.
[0686] Viability of nematodes in carbon monoxide based atmospheres.
30-60 embryos were harvested from continuously maintained Bristol
N2 and hif-2(ia04) strains as described above. Environmental
chambers were continuously perfused at room temperature with pure
CO (grade CP) or 500 ppm O.sub.2/CO at 70 cc/min for 24 hrs. To
achieve 2500 ppm O.sub.2/CO or 2500 ppm O.sub.2/N.sub.2, 5000 ppm
O.sub.2/N.sub.2 was mixed at a 1:1 ratio with either pure CO or
pure N.sub.2 using two mass flow controllers (Sierra Instruments
810) to precisely monitor flow. Each gas was delivered into a 3-way
valve (Cole-Parmer #A-30600-23) at 50 cc/min and the resulting
mixture was then passed through a gas washing bottle and into an
environmental chamber throughout the 24 hour exposure. All gases
were supplied by Byrne Gas (Seattle, Wash.). The 500 ppm O.sub.2/CO
mixture was certified to .+-.2% of the oxygen content and contained
7000 ppm N.sub.2 to ensure a consistent O.sub.2/CO ratio throughout
the use of the tank.
[0687] Cell biological analysis. To determine the extent of
developmental progression in nitrogen-based atmospheres (Table 2),
2-cell embryos were exposed to various degrees of hypoxia as
described above and were either immediately photographed, or
photographed following a 12 hr recovery period in a humid chamber.
To determine whether embryos arrested in carbon monoxide-based
atmospheres, 2-cell embryos were aged in room air for two hours and
were either photographed immediately or put into 100% carbon
monoxide or 0.05 kPa O.sub.2/CO for 24 hours and photographed
immediately following the exposure. In all cases, DIC microscopy
was done by placing embryos under a cover slip on a thin 1% agarose
pad and viewing on a Zeiss axioscope. Photographs were taken using
RS Image and Adobe Photoshop software.
[0688] B. Results
[0689] HIF-1 has been previously reported to be required in C.
elegans in mild hypoxia (0.5 kPa O.sub.2 (Padilla et al., 2002) and
1 kPa O.sub.2 (Jiang et al., 2001)) and suspended animation is
known to be possible in anoxia (>0.001 kPa O.sub.2) (Padilla et
al., 2002). To precisely define the ranges in which each of these
responses are active, the viability of wild-type C. elegans embryos
was determined following exposure to various oxygen tensions
between mild hypoxia and anoxia for 24 hrs. Embryos exposed to
anoxia entered suspended animation as previously reported, and thus
survived the exposure with high viability. Embryos in 0.5 kPa
O.sub.2 remained animated throughout the exposure and also survived
with high viability. However, embryos exposed to an intermediate
range of oxygen tensions between mild hypoxia and anoxia (0.1 kPa
O.sub.2 to 0.01 kPa O.sub.2) surprisingly did not survive (FIG.
2).
[0690] Embryos did not hatch during exposure to this intermediate
range of hypoxia, indicating that they did not successfully execute
the HIF-1 mediated response. To determine if they appeared
suspended, it was examined whether embryos in this intermediate
range arrested embryogenesis during the exposure. Embryos in lethal
oxygen tensions did not arrest embryogenesis, and increased amounts
of oxygen correlated with an increase in the extent of
developmental progression in the embryo (Table 2). Upon
reoxygenation, the majority of these embryos failed to hatch and
many of those that did hatch arrested as abnormal L1s. These data
show that this intermediate range of hypoxia is a unique stress in
which oxygen levels are neither sufficiently high to facilitate
continued animation nor sufficiently low to induce suspended
animation.
[0691] Based on these findings, it was hypothesized that if carbon
monoxide, a competitive inhibitor of oxygen binding, could induce
suspended animation in the presence of low levels of oxygen, it
would provide protection against this lethal range of hypoxia. To
examine this possibility, the viability of C. elegans embryos in
various concentrations of carbon monoxide was first determined.
Despite the toxic effects that high levels of carbon monoxide can
have in some systems, C. elegans embryos was found to be remarkably
tolerant to a wide range of carbon monoxide tensions. In fact, C.
elegans embryos can withstand a continuous exposure to 101 kPa CO
(100% CO) for 24 hrs with high viability (81.5% survival to
adulthood, FIG. 3). Notably, in 101 kPa CO, embryos did not
progress through embryogenesis during the exposure, indicating that
they entered into suspended animation. To test whether carbon
monoxide could protect embryos in the presence of lethal oxygen
tensions, the viability of embryos exposed to 0.05 kPa O.sub.2
balanced with carbon monoxide was determined. In contrast to
embryos exposed to 0.05 kPa O.sub.2 balanced with N.sub.2 (most of
which do not survive), these embryos recovered with 96.2% viability
to adulthood (FIG. 3). Moreover, like embryos treated with 101 kPa
CO, embryos in 0.05 kPa O.sub.2 balanced with carbon monoxide
arrested embryogenesis, indicating that they entered into suspended
animation. Therefore, carbon monoxide can protect against hypoxic
damage in the presence of lethal oxygen tensions by inducing
suspended animation.
[0692] To further examine the range of oxygen tensions that can be
protected by excess carbon monoxide, embryos lacking HIF-1 function
(the hif-1 (ia04) strain) were used to address whether protection
against hypoxic damage was also possible in mild hypoxia. After
testing various oxygen tensions between 0.1 kPa O.sub.2 and 1 kPa
O.sub.2 balanced with nitrogen, it was found that the maximal
requirement for HIF-1 was in 0.25 kPa O.sub.2 balanced with
nitrogen. In this atmosphere, wild-type embryos progress normally
through development and exhibit high viability, but hif-1 (ia04)
embryos do not complete embryogenesis and exhibit 100% lethality
(Table 3). Therefore, it was examined whether carbon monoxide could
protect hif-1 (ia04) embryos in 0.25 kPa 2. In 0.25 kPa O.sub.2
balanced with carbon monoxide, both wild-type and hif-1 (ia04)
embryos entered into suspended animation and survived the exposure
with high viabilities (78.7% and 84.0% survival to adulthood,
respectively) (Table 3). Thus, the induction of suspended animation
by carbon monoxide is possible at oxygen tensions as high as 0.25
kPa O.sub.2, and carbon monoxide can protect against mild hypoxia,
even in the absence of HIF-1 function.
TABLE-US-00005 TABLE 2 Quantitation of developmental progression in
hypoxia Percent of Range of embryos within embryogenesis Atmosphere
range (min post 2-cell stage) N >0.001 kPa O.sub.2/N.sub.2 100%
.+-. 0.0 20-40 min 35 0.01 kPa O.sub.2/N.sub.2 92.9% .+-. 6.0 40-80
min 115 0.05 kPa O.sub.2/N.sub.2 97.7% .+-. 2.0 100-140 min 108 0.1
kPa O.sub.2/N.sub.2 91.4% .+-. 1.3 300-340 min 60
Wild-type 2-cell embryos were placed into various degrees of
hypoxia for 24 hrs and scored for the extent to which they
progressed through embryogenesis. Exposure to atmospheres
containing increased amounts of oxygen resulted in increased
progression through embryogenesis. The percent of embryos that
arrested within a given 20-40 minute range of embryogenesis was
determined. Data are the result of 3 independent experiments.
TABLE-US-00006 TABLE 3 Carbon monoxide protects hif-1 embryos
against mild hypoxia 0.25 kPa O.sub.2/N.sub.2 n 0.25 kPa O.sub.2/CO
N N2 94.2% .+-. 1.2 49 78.7% .+-. 21.9 109 hif-1(ia04) 0.0% .+-.
0.0 68 83.9% .+-. 13.8 108
[0693] Viabilities to adulthood were assayed following exposure to
24 hrs of 0.25 kPa O.sub.2/N.sub.2 or 0.25 kPa O.sub.2/CO in
wild-type and hif-1 (ia04) embryos. All data points are the result
of at least 3 independent experiments and worms that could not be
accounted for were dropped from the total.
Viability of Nematodes in Response to Hypothermia.
[0694] Viability of nematodes is also temperature sensitive, with
100% of a population being dead after a 24 hr exposure to cold
temperature (4.degree. C.; FIG. 15). However, if the nematodes are
induced into stasis by equilibration into anoxic conditions (<10
ppm oxygen) for 1 hr prior to the temperature drop, a substantial
proportion of them survive after a 24 hr exposure to 4.degree. C.
(FIG. 15). In this experiment, the nematodes were kept in stasis
during the period of hypothermia, and for one hour after they have
been returned to room temperature. Anoxic conditions (pure
N.sub.2), growth conditions, and viability measurements are
described below.
Example 4
Reduction of Core Body Temperature and Respiration in Mice
[0695] A. Materials and Methods
[0696] Implantation of telemetry devices. Female C57BL/6J mice
(Jackson Laboratories--Bar Harbor, Me.) were implanted with
telemetry devices (PDT-4000 HR E-Mitter--MiniMitter Inc.--Bend,
Oreg.) according to standard protocol provided by the manufacturer.
Mice were allowed to recover for several weeks to permit body
temperature and heart rate signals to stabilize. Core body
temperature, heart rate, and movement of the mice were continuously
monitored via the telemetry devices and recorded using VitalView
software (provided by MiniMitter). Ambient temperature was
monitored using a HOBO (Onset Computer Corp.--Pocasset, Mass.) and
the data analyzed using BoxCar software (provided by Onset Computer
Corp.).
[0697] Exposure of Mice to Regulated Atmosphere. Each mouse was
exposed to 1 L/min of either (a) an atmosphere containing 500 ppm
H.sub.2S balanced nitrogen (Byrne Specialty Gas--Seattle, Wash.)
mixed with room air (using a 3 channel gas proportioner meter from
Aalborg--Orangeburg, N.Y.) to give a final concentration of 80 ppm
H.sub.2S and 17% O.sub.2, or (b) an atmosphere of nitrogen mixed
with room air to give a final concentration of 17% O.sub.2.
H.sub.2S and O.sub.2 measurements were taken using an Innova
GasTech GT series portable gas monitor (Thermo Gas Tech--Newark,
Calif.).
[0698] Prior to and during exposure to testing in regulated and
unregulated atmospheres, the mice were placed in a gassing chamber
comprising a glass cage (with drinking water and no food) fitted
with import and export tubes of FEP tubing from Cole-Parmer (Vernon
Hills, Ill.) for introduction and venting of the atmosphere. The
cage was sealed with a lid using Dow Corning silicone vacuum grease
(Sigma--St. Louis, Mo.). The gas from each cage was vented through
the export tube into the chemical hood. To ensure that the system
was gas-tight, a GasTech GT portable monitor was used to detect
leaks.
[0699] Respirometry. In some experiments, the consumption of oxygen
was measured by use of a PA-10a O.sub.2 analyzer (Sable Systems)
which was used according to manufacturers instructions. Similarly,
the carbon dioxide being produced by the animals was monitored
using a LI-7000 CO.sub.2/H.sub.2O analyzer (Li-Cor company) used
according to the manufacturers instructions. These instruments were
placed in line with the environmental chambers such that they
sample the gas import and export tubing.
[0700] Regulation of Ambient Temperature. Mice were housed in a
Shel Lab low temperature diurnal illumination incubator (Sheldon
Manufacturing Inc.--Cornelius, Oreg.) to regulate both temperature
and light cycle (8 AM lights on, 8 PM lights off) for the mice.
Mice were exposed to regulated atmosphere as described above. When
the mice were exposed to the regulated atmosphere, the temperature
inside the incubator was dropped to the desired temperature, for
example, to 10.degree. C. or 15.degree. C. The mice were maintained
in the regulated atmosphere and at the lowered temperature for six
hours. The atmosphere in the gassing chamber was replaced with room
air and the mice were returned to normal room temperature
(22.degree. C.) and allowed to recover.
[0701] B. Results
[0702] Baseline Data. To determine the response of mice to
sub-lethal doses of hydrogen sulfide, the inventor first
established baselines of core temperature, heart rate and movement
by recording data over a one-week period from four mice with
implanted transceivers in the incubator held at ambient temperature
and perfused with room air. The baseline data demonstrated that the
mice have a circadian rhythm with peak of activity in the evening
just after the lights are turned off, and in the early morning just
before the lights are turned on. The core temperature varied from a
high of 37.degree. C. during their active periods to a low of
33.5.degree. C. during their inactive periods. The heart rate
varied from 750 bpm (beats per minute) during their active periods
to 250 bpm during their inactive periods. Heart rate is likely to
be correlated with core temperature (higher temp higher heart
rate). Likewise gross motor movement was highest during the evening
and just before dawn.
[0703] Exposure of Mice to Regulated Atmospheres at Room
Temperature. The first trial of the exposure of a mouse to hydrogen
sulfide involved first placing the mouse into the gassing chamber
held at 27.degree. C. in the incubator for one hour. After the
hour, the chamber was perfused with 80 ppm as generally described
above and the temperature of the incubator was lowered to
18.degree. C. for the duration of the experiment. While no
immediate changes in heart rate and gross motor movement were
detected, a dramatic decrease in core temperature was observed. The
experiment was allowed to proceed for 90 min. during which time the
core temperature dropped to 28.6.degree. C.--five degrees below the
lowest recording for any of the four mice in the baseline study
described above. During recovery after the chamber was perfused
with room air, the inventor noticed that the animal at first was
relatively immobile (easy to catch); however within 60 min. it had
returned to a normal range of core temperature and activity. A
second mouse was exposed to the same protocol; however this time
the gassing at 80 ppm was conducted for 3 hrs. During this time,
the inventor noted that heart rate dropped significantly from 600
bpm to 250 bpm, gross motor movement showed almost no activity, and
the core temperature dropped to 18.6.degree. C.
[0704] Changes in respiration accompany the drop in core
temperature. Exposure of the mice to 80 ppm H.sub.2S results in
decreased metabolic rate as well, as determined by measuring oxygen
consumption and carbon dioxide production. For example, a mouse
that had core temperature and carbon dioxide production measured
simultaneously, demonstrated a rapid reduction in carbon dioxide
production preceding the drop in core temperature of the animal
(FIG. 4A). The approximately three-fold reduction in carbon dioxide
production established a new baseline in approximately 5 minutes
after the exposure to H.sub.2S.
[0705] Table 4 shows results from an experiment with concurrent
measurements of O.sub.2 and CO.sub.2 concentrations from mice
exposed to room air that had had the CO.sub.2 scrubbed (hence the 0
values for controls), with or without H.sub.2S (80 ppm).
Measurements were over a period of 15 minutes, with the mice in a
0.5 L sealed environmental chamber with flow rates of 500 cc/min.
Consumption of oxygen is obtained by subtracting the oxygen
concentration when the mouse is present, from the control when the
mouse is absent. Likewise, production of carbon dioxide is obtained
by subtracting the carbon dioxide concentration when the mouse is
present from the control when the mouse is absent. RQ stands for
respiratory quotient, and is equal to the ratio of carbon dioxide
produced to oxygen produced. This result demonstrates, a 2-3 fold
drop in oxygen consumption in the presence of H.sub.2S, as well as
a 3-4 fold drop in carbon dioxide production. The change in the
respiratory quotient reflects the disparity oxygen consumption and
carbon dioxide production by the mice in the presence or absence of
the H.sub.2S.
TABLE-US-00007 TABLE 4 H.sub.2S exposure inhibits respiration in
mice. Mouse present H.sub.2S present [O.sub.2] ppm [CO.sub.2] ppm
RQ - - 207,000 0 + - 203,600 2800 Consumption, production 3,400
2800 0.82 - + 166,200 0 + + 164,900 750 Consumption, production
1300 750 0.58
[0706] The different parameters of stasis (reduction in oxygen
consumption, decrease in carbon dioxide production or decrease in
motility) can be assessed by a variety of assays and techniques.
For example, probably the easiest way to measure the induction of
stasis in mice administered H.sub.2S is through observation of
their breathing. Indeed, this encompasses all three parameters in
that it is indicative of decreased oxygen consumption, carbon
dioxide production and motility. A normal mouse in room air at
standard conditions will take approximately 200 breaths per minute.
If H.sub.2S is administered to the mouse at 80 ppm, and the core
temperature is dropped to 15.degree. C., breathing is decreased at
least an order of magnitude to somewhere between 1-10 breaths per
minute. In fact, a mouse was observed under these conditions that
did not take a breath for a period greater than an hour, indicating
that deep levels of stasis are attainable. Thus, this represents at
least about a 1-20-fold decrease in cellular respiration (i.e.,
oxygen consumption and carbon dioxide production).
[0707] Exposure of Mice to Regulated Atmospheres at Reduced Ambient
Temperatures. To begin to define the limits of the capacity for
hydrogen sulfide to reduce the activity in mice, the inventor
conducted several experiments in which a non-telemetry mouse was
used, followed by exposure of a mouse bearing telemetry to acquire
the data. The first experiment was to subject a non-telemetry mouse
to a regulated atmosphere of H.sub.2S at 80 ppm in a reduced
cabinet temperature of 10.degree. C. essentially as described in
Materials and Methods were as above except that the mouse was
placed in the gassing chamber for one hour at 27.degree. C. prior
to exposure to the gas and reduction in ambient temperature. The
non-telemetry mouse did well in this treatment, and recovered
activity within approximately 90 min. after removal from the
gassing chamber. The telemetry mouse was subjected to the same
conditions also did well, and showed decreased core temperature to
approximately 12.5.degree. C. The inventor was unable to accurately
determine this temperature because the electronics failed at
15.3.degree. C. The temperature drop to 12.5.degree. C. is
therefore an estimation based on the slope of the drop prior to
failure and the time the animal remained in the chamber after
failure of the electronics.
[0708] Because of the limitation of the equipment, the inventor
next tested each of the four telemetry mice for a 6 hr period in
the gassing chamber with a regulated atmosphere containing
approximately 80 ppm hydrogen sulfide or with room air essentially
as described above. The temperature of the incubator was reduced at
initiation of the experiment (exposure to the regulated atmosphere,
or time 0 for the mice exposed to room air) to a constant
15.degree. C. At the end of the six-hour period, the mice were
returned to an atmosphere of room air and an ambient temperature of
22.degree. C. as generally described above. There was a clear
decrease in core body temperature in all four mice that was
dependent on the use of 80 ppm hydrogen sulfide (FIG. 4B). There
was also a marked drop in heart rate and gross motor movement
associated with the decrease in temperature. The mice were
maintained for 4 weeks with no apparent change in the behavior of
the animals.
Example 5
Murine Studies on Reduction of Radiation Injury
[0709] A. Scientific Rationale
[0710] While aspects of the radiation injury model can and have
been evaluated in cell culture, to test the ability of an
experimental drug to affect the injury and healing process requires
inclusion of all of the response systems that are affected. At this
point in time, the only way to achieve that is in a whole animal.
The inventor is proposing the use of mice for such studies as the
most appropriate model. The C57BL/6 mice have been selected for
study because this strain of mouse is readily susceptible to
radiation lung injury, the level of radiation that is tolerated in
this strain has been established, and the inventor has recently
shown that H.sub.2S decreases the core temperature of this mouse
strain.
[0711] Two identical experiments are planned under this protocol.
Each experiment will investigate the efficacy of H.sub.2S-induced
hypothermia on the development of radiation induced lung injury.
Ten mice per group will be exposed to one of four test conditions
(H.sub.2S/17.5 Gy thoracic irradiation, H.sub.2S/no thoracic
irradiation, no H.sub.2S/17.5 Gy thoracic irradiation, or no
H.sub.2S/no thoracic irradiation), then followed for 13 weeks.
Twelve animals per group will be similarly exposed and followed for
26 weeks (the increased n is required to compensate for the
increased mortality that occurs late in the course of the
disease).
[0712] For these experiments, analysis of variance (ANOVA) will be
used as the statistical model for data analysis. A completely
crossed and randomized two factor ANOVA with 4 groups (irradiated
or non-irradiated mice receiving H.sub.2S or not receiving
H.sub.2S) and two time intervals (13 or 26 weeks) will be used to
analyze temporal changes in bronchoalveolar lavage inflammatory
cell number and total protein concentration and lung hydroxyproline
levels. Assuming 80% power, 5% significance and a two-tailed test,
five surviving mice per combination of injury group, intervention
group and time point will allow a detectable difference among group
means greater than or equal to 1.7 times the underlying
within-group standard deviation. The within-group standard
deviation is expected to be equal to about 25%. Thus, changes in
inflammatory cell numbers or lung collagen content of 35-50% of
control values should be discernable in these experiments.
[0713] H.sub.2S exposure and thoracic irradiation will be done in
SLU AHR in a linear accelerator suite. Bronchoalveolar lavage and
lung procurement at necropsy will be performed in the AHR mouse
necropsy room. Bronchoalveolar lavage cell counts and protein
concentrations and lung hydroxyproline content measurements will be
performed in the another lab (D3-255). Wild genotype C57BL/6 mice
will receive 17.5 Gy of thoracic irradiation. Mice will be
anesthetized with intraperitoneal Avertin, placed into individual
cloth mouse restrains and irradiated via the linear accelerator
with 8.5 Gy at a dose rate of 3 Gy/min through two lateral fields
collimated to target the thorax only (total thoracic dose 17.5
Gy).
[0714] B. Protocol
[0715] Anesthesia. Wild genotype C57BL/6 mice will be anesthetized
for intratracheal dosing with Isoflurane. The depth of anesthesia
will be monitored by respiratory rate for response to tactile
stimulation. Intrapenitoneal injection of Avertin (0.4-0.7 ml/mouse
i.p.) will be used to anesthetize animals for the thoracic
irradiation procedure. The depth of anesthesia will be monitored by
respiratory rate and response to tactile stimulation.
[0716] Exposure to hydrogen sulfide. Mice will be placed into a
closed plexiglass gassing chamber similar to the one used
previously for mice (IR1606). The chamber will have two ports
(import and export). A gas containing H2S (80 ppm) balanced with
room air will be vented through the chamber at a rate of 1 liter
per minute. The gas will be vented from the room using the house
ventilation system with a hose that extends from the export vent to
the exhaust vent for the room.
[0717] Hazardous agent administration. Mice will be irradiated
while they are in the gassing chamber with a total dose of 17.5
Gray using the linear accelerator. This radiation dose will induce
an subacute pulmonary injury in the mice which progresses to
fibrosis. The mice will not be radioactive or otherwise provide a
hazard to personnel or other animals. No special monitoring,
containment or disposal is required due to the irradiation.
[0718] Scheduled euthanasia. At approximately weeks 13 and 26 after
thoracic irradiation, the animals will be euthanized by deep
anesthesia (using avertin 0.4-0.7 ml i.p.) followed by
exsanguination via inferior vena cava puncture. Bronchoalveolar
lavage will be performed to determine inflammatory cell number,
differential counts and lavage fluid protein concentrations. Lung
and esophagus tissue will be removed for histologic evaluation and
collagen content analysis.
[0719] Moribund animals. Thoracic radiation is associated with a
finite mortality rate in mice, with 15% dying by week 10 and 50% by
week 22 post irradiation. The investigators will monitor the
animals daily for adverse effects (2-3 times per day initially,
until they appear stable, then once daily until disease begins to
progress, at which point the inventor will return to multiple daily
observations). If an animal is losing weight, failing to groom,
exhibiting severe respiratory distress, and/or awkward or
significantly diminished movement, it will be euthanized with an
avertin overdose. When practical, bronchoalveolar lavage and tissue
collection for histology will be performed for these unscheduled
euthanasias.
[0720] Thoracic irradiation should produce a lung injury which
itself is not painful but may manifest itself (week 10) by
increased respiratory rate, mild appetite loss, mild weight loss
and/or failure to groom. The investigators and animal facility
staff will monitor the animals daily for such adverse effects. If
an animal does not seem to be eating, soft food and fluid support
will be provided. If the animal is perceived to be in pain,
analgesia with Butorphanol (0.2 mg/kg i.p.) or Buplirenorphine (1.0
mg/kg bid s.q.) will be administered as needed. If an animal
appears to be suffering and palliative measures do not lead to
improvement, it will be euthanized immediately. Lung and esophagus
tissue will be collected for histopathologic evaluation and
collagen content analysis at the scheduled necropsies.
[0721] Post-irradiation Husbandry. To minimize the risk of
transmitting any pathogens to the rest of the facility, and to
protect these animals while they are somewhat immunocompromised,
all husbandry work on these animals will be done first thing each
day (before any other animals in the facility) and will be done in
a biosafety cabinet. To minimize the risk of adventitious
infections, the mice will have autoclaved cages and bedding. In
addition, they will be fed standard rodent food that has been
irradiated to kill pathogens.
[0722] Wild genotype C57BL/6 mice will receive 17.5 Gy of thoracic
irradiation. Mice will be anesthetized with intraperitoneal
Avertin, placed into individual cloth mouse restraints and moved
into a closed plexiglass gassing chamber similar to the one used
previously for mice (IR1606). The chamber will have two ports
(import and export). A gas containing H.sub.2S (80 ppm) balanced
with room air will be vented through the chamber at a rate of 1
liter per minute. The gas will be vented from the room using the
house ventilation system with a hose that extends from the export
vent to the exhaust vent for the room. Once in the gassing chamber
the mice will be irradiated via the linear accelerator with 8.5 Gy
at a dose rate of 3 Gy/min through two lateral fields collimated to
target the thorax only (total thoracic dose 17.5 Gy). After
completion of thoracic irradiation the animals will be returned to
their micro-isolater cages monitored until recovered from
anesthesia.
[0723] Scheduled necropsises. One set of animals will be necropsied
in week 13 post-irradiation to evaluate the inflammatory phase of
the injury. The second set will be euthanized in week 26 to
evaluate the fibrotic phase of the injury. Animals will be
anesthetized with avertin, then exsanguinated. The lungs will be
lavaged with 1000 .mu.l PBS and the lavage fluid kept on ice for
total and differential cell counts. The right lung will then be
harvested for hydroxyproline content and the left lung will be
infused with 10% NBF at 25-30 cm pressure through the trachea. The
esophagus, trachea, left lung and heart will be immersed in 10% NBF
and set to the FHCRC histology shared resource lab for processing
and pathology evaluation.
[0724] Thoracic irradiation should produce a lung injury which
itself is not painful but may manifest itself (week 10) by
increased respiratory rate, mild appetite loss, mild weight loss
and/or failure to groom. The investigators and animal facility
staff will monitor the animals daily for such adverse effects. If
an animal does not seem to be eating, soft food and fluid support
will be provided. If the animal is perceived to be in pain,
analgesia with Batorphanol (0.2 mg/kg i.p.) or Buphrenorphine (1.0
mg/kg bid s.q.) will be administered as needed. If an animal
appears to be suffering and palliative measures do not lead to
improvement, it will be euthanized immediately by CO.sub.2
asphyxiation.
[0725] The primary problems are likely to be esophagitis (resulting
in decreased food and water intake) and respiratory insufficiency
(reducing oxygen uptake). The inventor will be checking these
animals 2-3 times per day until they are convinced that they are
stable and doing well, at which point the inventor may reduce the
frequency of checks to once daily, until the disease begins to
progress, at which point they return to multiple daily checks.
Supportive care will be provided in several ways. If an animal is
not eating or drinking well (evidenced by weight loss and grooming
problems), the inventor will provide soft food and try fluid
supplementation (Lactated Ringer's solution, 1-2 ml/mouse, sc using
a small bore needle (>20 G), 1-2 times daily). If the animal is
perceived to be in pain, analgesia with Batorphanol (0.2 mg/kg
i.p.) or Buphrenorphine (1.0 mg/kg bid s.q.) will be administered
as needed. If an animal appears to be suffering and palliative
measures do not lead to improvement, it will be euthanized
immediately by CO.sub.2 asphyxiation. In the event that an animal
experiences significant pain or distress at the time of thoracic
irradiation, the animal will be euthanized by CO.sub.2
asphyxiation.
[0726] A third experiment was to subject a telemetry mouse to a
regulated atmosphere of H.sub.2S at 80 ppm in a reduced cabinet
temperature of 10.5.degree. C. essentially as described above.
During the experiment, the mouse was visually observed and its
movements were recorded by web camera, and telemetry measurements
were recorded as described above. The mouse was exposed to a
regulated atmosphere of 80 ppm H.sub.2S, and the temperature of the
cabinet was reduced to a constant 10.5.degree. C. At the end of an
approximately six-hour period, heat was applied to the cabinet by
setting the cabinet temperature to 25.degree. C. The mouse was
allowed to warm up in the regulated H.sub.2S atmosphere until the
core temperature of the mouse was between 17.degree. C. and
18.degree. C. after which time the regulated atmosphere was
replaced with room air. There was a clear decrease in core body
temperature of the mouse to 10.5.degree. C. in the regulated
atmosphere accompanied by a marked drop gross motor movement. The
respiration rate dropped to an undetectable rate by visual
observation for approximately one hour and fifteen minutes. After
the cabinet was warmed, weak respiration was observed when the core
body temperature of the mouse achieved 14.degree. C. During the
warming phase, when the core body temperature rose to between
17.degree. C. and 18.degree. C., and the mouse was exhibiting
respiration and movement, the regulated atmosphere was replaced
with room air. Normal movement and respiration were fully apparent
when the core body temperature returned to 25.degree. C. The mouse
has exhibited no apparent change in the behavior compared to
animals that were untreated.
Example 6
Cell and Mammal Studies
[0727] A. Canine Studies
[0728] Canine studies will be conducted with dogs surgically
implanted with telemetry devices to monitor their core body
temperature. The animals will be studied in the presence or absence
of a sub-lethal dose of hydrogen sulfide for 10 hrs. During this
time, they will be continuously monitored for vital signs by
telemetry. The temperature of the environment will also be reduced
to 15.degree. C. for 30 min to determine whether this has any
effect on the core body temperature of the animals.
[0729] The procedure will be conducted with 2 groups of 2 dogs
(four total). Because of the expense of the telemetry equipment the
inventor will do these experiments in succession. If the results
from the first group indicate that the hypothesis is incorrect, the
study will be repeated with the second group of two dogs. If the
results from the second group do not support the hypothesis, the
project will be discontinued.
[0730] Toxicology studies demonstrate that, while the level of
H.sub.2S is above the OSHA limit for humans (10 ppm), it has been
shown previously that exposure of both rats and mice to 80 ppm of
H.sub.2S for 6 hrs per day, 5 days per week, for 90 days, showed no
observed adverse effect. This included both gross and
histopathological examination of the gut, lung, heart, liver,
kidneys, or other organs conducted at the end of the treatment. To
the inventor's knowledge, no information is available concerning
exposure of dogs to hydrogen sulfide.
[0731] A critical issue in working with H.sub.2S is to not exceed
the dose (80 ppm) described by others who have published studies on
rodents exposed to hydrogen sulfide and not seen detrimental
effects. There is considerable experience in gas sciences
available, and the inventor is capable of delivering the gas to the
mice at the prescribed dose. Many precautions are taken to ensure
that both animals and investigators are not harmed. These
precautions include constant monitoring of the gas mixture with
alarm set to OSHA limits and sensitivity to 1 ppm, and a variety of
equipment that is able to mix and deliver the gas according to
specifications without leakage into or out of the system.
[0732] A time line for the protocol is given in Table 5.
TABLE-US-00008 TABLE 5 Study Time Line Day Activity Detail -1
Pre-surgery A CBC/Chemistry will be performed; dog will be fasted
in p.m., but allowed free access to water. 0 Surgery Fentanyl
transdermal patch placed p.m. of day before surgery for preemptive
analgesia. Preoperative placement of cephalic catheter;
premedication with Acepromazine, Buprenorphine, Glycopyrrolate;
induction with either Ketamine:Diazepam or Propofol to permit
intubation; maintenance anesthesia by isoflurane and oxygen. Dog
will be placed in dorsal recumbancy and the abdomen clipped/prepped
and draped. Monitoring of pulse, respiration rates, end-tidal
carbone dioxide, inhaled percentage of anesthetic agent, SpO.sub.2
will be performed and recorded every 15 minutes or more frequently.
Fluid support during and after surgery will occur. Once the dog is
stable and appropriately prepared for the procedure, a ventral
midline laparotomy, beginning caudal to the umbilicus and extending
5-10 cm caudally, will be performed. A sterile transmitter will be
placed into the peritoneal cavity. Placement will be checked to
insure that the transmitter is able to move freely; the momentum
will be replaced, and closure of the peritoneal cavity will be
performed in 3 layers. The dog will be monitored until it is
extubated, is able to thermoregulate and is sternally recumbent.
Daily monitoring of the dog's incision site, abdomen (via palpation
and ultrasound, if indicated), appetite, temperature (for the first
3-5 post-operative days), weight and activity will be performed. 7
Establishment This date is flexible. Will only proceed with this
step with of Baselines approval. Four animals will be placed onto
the receiver equipment (this does not involve removal of the
animals from their cages and will occur in AHR) and baselines for
the vital signs will be established for all four animals. 8
Exposure to Animals will be transferred to a room to be determined
where H.sub.2S they will be placed into caging with food and water
that has an enclosed atmosphere. After establishing baselines two
of the four animals will be subjected to H.sub.2S at a
concentration of 80 ppm. Following a ten-hour exposure, the
atmosphere will be returned to room air temperature and the animals
will be returned to their cages. Exposure to H.sub.2S will repeated
once per week to begin to determine whether any data set is
reproducible.
[0733] B. Human Platelets
[0734] To test the concept that using inhibitors of oxidative
phosphorylation could be used for human benefit, the inventor
induced a state of suspended animation in human tissues to protect
them from lethal exposure to oxygen. In pilot experiments, the
inventor placed human skin in an environment of 100% CO. The
inventor observes that after 24 hrs skin cells survive 100-fold
better in CO than those in room air. These results are very
exciting; they provide evidence that inhibitors of oxidative
phosphorylation can be effective in human tissues.
[0735] Another set of experiments demonstrates the protective
effects of induced suspended animation on platelets. A unit of
platelets was split in half. The first half was kept at standard
storage conditions, which involves keeping the platelets at room
temperature (22-25.degree. C.) with constant shaking. The other
half was placed inside an anoxic environment (<10 ppm oxygen)
using standard methods to remove the oxygen. The two sets of
platelets were compared on days 0, 5 and 8. The platelets kept in
anoxic conditions performed as well or better than those kept at
standard conditions over a panel of five different in vitro tests,
including the ability to aggregate, cell morphology, Annexin-V
staining (phosphatidyl-serine flipping to the outer membrane as an
early apoptotic marker), and so on. This indicates that controlling
metabolic activity, specifically oxidative phosphorylation, can be
accomplished by the removal of oxygen and has a protective effect
on cellular function over long periods of stasis.
[0736] Hydrogen sulfide is able to bind cytochrome C oxidase as
well as CO and stop oxidative phosphorylation on demand. It is so
potent at impeding oxidative phosphorylation, that should a person
take a single breath in an atmosphere with 0.1% hydrogen sulfide,
they will not take another. Instead, they immediately collapse to
the floor--an event commonly referred to in industrial settings as
a "knock down." It also appears to be reversible because, if
rapidly removed to fresh air (and uninjured from the fall) these
individuals can sometimes reanimate and go on to live without
neurological problems. Here is an agent that is not only common in
our world, indeed, is produced even in our own cells, but is also a
potent reversible inhibitor of oxidative phosphorylation that does
not effect oxygen delivery.
[0737] C. Murine Studies
[0738] Induction of a Hibernation-Like State Using H.sub.2S.
Homeothermic animals, by definition, maintain a core body
temperature 10-30.degree. C. above the ambient temperature. For
these animals to do this, they must generate heat from the energy
produced by oxidative phosphorylation. The terminal enzyme complex
in oxidative phosphorylation is cytochrome c oxidase. Since
hydrogen sulfide inhibits this complex (Petersen, 1977; Khan et
al., 1990), the inventor predicts that exposing a homeothermic
animal to hydrogen sulfide will prevent such an animal from
maintaining its core body temperature well above ambient
temperatures.
[0739] To test this hypothesis, the inventor wanted to continuously
monitor both the core body temperature and the activity levels of a
homeothermic animal (a mouse). Telemetry devices, implanted into
the peritonea of mice, can do both of these things and have the
advantage of not introducing bias to the readings due to the
handling of the mice (Briese, 1998). Additionally, they can
remotely monitor the mice during the exposure to the hydrogen
sulfide gas. A dose of 80 parts per million (ppm) hydrogen sulfide
has been previously shown to be innocuous to mice for exposures
lasting up to ten weeks (CIIT 1983; Hays, 1972). Therefore, for
these experiments the inventor used a dose of 80 ppm hydrogen
sulfide to test our hypothesis. Creating an atmosphere containing
80 ppm of hydrogen sulfide is not trivial. Over time, in the
presence of oxygen, hydrogen sulfide will be oxidized to sulfate.
For that reason, in order for the inventor to continuously expose a
mouse to an atmosphere containing 80 ppm hydrogen sulfide, the
inventor constantly mixes room air with a tank of 500 ppm hydrogen
sulfide balanced nitrogen.
[0740] Characterization of Core Temperature Control
[0741] Exposing a mouse to 80 ppm H.sub.2S dropped its core
temperature to approximately two degrees Celsius above ambient
(FIG. 5). This effect was highly reproducible as the average core
body temperature of seven mice exposed to 80 ppm of hydrogen
sulfide for 6 hrs followed a similar pattern (FIG. 5). The lowest
average core body temperature of these seven mice was 15.degree. C.
in an ambient temperature of 13.degree. C. All of these mice
successfully recovered after rewarming when the atmosphere was
switched to one containing only room air. As a control, the
inventor substituted nitrogen for the hydrogen sulfide and did not
see the substantial drop in core body temperature.
[0742] Although these mice appear superficially normal despite
temporary decrease in both core body temperature and breathing
rate, the inventor conducted a battery of behavior tests to rile
out the possibility that neurological damage was incurred by either
the exposure to hydrogen sulfide gas, the extreme reduction in core
body temperature, the reduction in breathing rate, or the
combination of these effects. All of the tests were performed on
the mice both before and after exposure to hydrogen sulfide. These
behavior tests were selected from the SHIRPA protocol developed by
the Mouse Models for Human Disease consortium (Rogers et al.,
1997). There were no detectable behavioral differences in the mice
after gas exposure. From this, the inventor concluded that entry
into a hibernation-like state is not detrimental.
[0743] Preliminary Optimization of H.sub.2S Dose. The above
experiments describe the effect of 80 ppm of hydrogen sulfide on
the core body temperature of a mouse. In order to determine the
concentration of hydrogen sulfide sufficient for the loss of
thermoregulation, the inventor exposed mice to a range of hydrogen
sulfide concentrations (20 ppm, 40 ppm, 60 ppm, and 80 ppm), (FIG.
6). While 20 ppm and 40 ppm of hydrogen sulfide were sufficient to
cause a drop in the core body temperature of a mouse, this was
minor compared to the drop seen with 60 ppm and 80 ppm of hydrogen
sulfide. From this experiment, the inventor concluded that the loss
of thermogenesis is directly dependent upon the concentration of
hydrogen sulfide given to the mice. This preliminary study on the
dose range and pharmacokinetics of hydrogen sulfide emphasizes the
need for a more comprehensive analysis.
[0744] Preliminary Definition of Low Core Temperature Limit. The
inventor is also interested in establishing a more complete
understanding of the tolerance of both the range of core body
temperatures and the length of time allowed in this state for mice.
The experiments above show that the inventor can repeatedly lower
the core body temperature of a mouse to 13-15.degree. C. on demand.
Furthermore, the mice seem to tolerate the treatment for many
hours. Using the same protocol, while lowering the ambient
temperature, the inventor has successfully brought the core body
temperature of a mouse to 10.7.degree. C. (FIG. 7). Further
attempts to push core body temperatures even lower, and for longer
periods of time, will be performed in the future. Although
preliminary, these results demonstrate that there is a significant
range of core body temperatures allowed by mouse biology and that
this range can be explored through the loss of thermoregulation due
to hydrogen sulfide exposure.
[0745] Modulation of Endogenous H.sub.2S Levels. It is well known
that mammalian cells make hydrogen sulfide endogenously (Wang
2002). Since this chemical is dynamically produced in the cell, it
is crucial to understand the basal levels under different
conditions as this could dramatically affect the pharmacokinetics
of exogenously administered hydrogen sulfide. To address this
essential aspect of our research, the inventor has begun to assay
endogenous hydrogen sulfide levels in the mouse. The inventor uses
an extractive alkylation technique coupled with gas chromatography
and mass specific detection to quantify hydrogen sulfide (Hyspler
et al., 2002). Using this method, the inventor looked at the levels
of hydrogen sulfide in unperturbed mice. FIG. 8A shows that there
is a significant amount of hydrogen sulfide within the mouse.
Additionally, the levels of hydrogen sulfide appear to be dependent
upon the ambient temperature of the mouse. Specifically, when mice
are in the cold, they have reduced endogenous sulfide levels and,
when mice are at warm ambient temperatures, they have increased
endogenous sulfide levels. From this, the inventor concludes that
mice regulate their sulfide levels in response to the ambient
temperature.
[0746] Changes in Endogenous Levels Affect the Efficacy of
H.sub.2S. Since the ambient temperature changes the endogenous
levels of sulfide in mice, the inventors hypothesized that the
ambient temperature might impact the changes in core body
temperature upon exposure to exogenous hydrogen sulfide.
Acclimatizing a mouse to cold temperatures, .about.12.degree. C.,
creates a longlasting plateau that the inventor sees after the
initial drop in core body temperature (FIG. 8B). Therefore it
appears that this acclimatization to the cold made the mouse more
resistant to core body cooling by the action of hydrogen sulfide
gas. However, allowing the mouse to acclimatize to a warm
thermoneutral temperature prior to gas exposure eliminates this
plateau. In fact, the normothermic mouse cooled much more quickly
when exposed to hydrogen sulfide than the cold-acclimated mouse
(FIG. 8B). These data suggest that endogenous levels of hydrogen
sulfide in the mouse have a direct impact upon the efficacy of the
exogenous hydrogen sulfide.
[0747] H.sub.2S protects mice from hypoxia. Normal room air
contains approximately 21% oxygen. In a preliminary experiment
exploring the protective effects of stasis on hypoxia in the mouse
model, a mouse exposed to 80 ppm of hydrogen sulfide survived 11
minutes of 5.2% oxygen and 3 weeks later, it was still doing well.
Previously published work shows that 90% of these animals (C57Bl)
exposed in this way without hydrogen sulfide do not survive (Zhang
et al., 2004). This experiment involved pre-equilibrating the mouse
to 80 ppm H.sub.2S for 3 hours, then dropping the oxygen tension in
the chamber as described in experiments above. The same flow rates
were used as described above (i.e., 500 cc/mL in a 0.5 L chamber).
It is well established in those familiar with the field that if a
group of mice are exposed to 4% oxygen, 100% will be dead within 15
minutes. However, mice in which H.sub.2S is administered during
periods when the oxygen tension is reduced to 4%, remain viable,
even for extended periods (up to an hour) in these hypoxic
conditions. The mice appear to be unaffected by these conditions
after recovery, and are viable and normally responsive when tested
24 hours later. This experiment differs from the one above in that
the mice were retained in the H.sub.2S at the end of the hypoxic
exposure until the oxygen tensions were returned to normal levels
(21% O.sub.2).
Example 7
Additional Animal Studies
[0748] A. Protection from Adverse Conditions
[0749] Experiments were conducted to test the ability of a mouse in
a `hibernation-like` state to survive in conditions where it would
normally die. The adverse condition was hypoxia, which the
literature states that mice (C57BL6/J males) can live in for a
maximum of 20 minutes at 5% Oxygen. (Zhang et al. 2004).
[0750] As shown in Table 6, the experiment involved exposing the
mouse to 80 ppm (unless otherwise noted) H.sub.2S for the time
indicated, followed by the decrease in oxygen tension in the
chamber, while still under H.sub.2S. The hypoxic exposure was timed
(indicated below) and viability of the mice was determined.
[0751] Short exposures of the mice to H.sub.2S (at least at 80 ppm)
was less successful at protecting the mouse from hypoxia, although
there was at least one that did survive a 50-minute hypoxic
exposure after just 8 minutes in H.sub.2S. Furthermore, it was
observed that a mouse exposed to 90 ppm H.sub.2S for just 10
minutes did survive much longer in the 5% Oxygen condition,
although it did eventually expire.
[0752] Exposing the mice to 80 ppm H.sub.2S for longer periods of
time had a strong effect on protecting them from hypoxia for up to
an hour.
TABLE-US-00009 TABLE 6 Time in H2S Ambient Prior to hypoxic Time in
Temp exposure Oxygen % Hypoxia Result 20.degree. C. 5 hrs 5.20% 11
minutes life 20.degree. C. 5.5 hrs 5.00% 25 minutes life 20.degree.
C. 5 hrs 5.00% 60 minutes life 20.degree. C. 5 hrs 4% 28 minutes
life 24.degree. C. no H2S 5% 14 minutes dead 24.degree. C.
simultaneous 5.10% 10 minutes dead 24.degree. C. 8 minutes 5% 20
minutes dead 24.degree. C. 8 minutes 4.00% 8 minutes dead
24.degree. C. 8 minutes 4.50% 23 minutes dead 30.degree. C. 8
minutes 4.50% 6 minutes dead 24.degree. C. 10 minutes 5% 56 minutes
dead (90 ppm) 24.degree. C. 8 minutes 5.00% 50 minutes life
[0753] B. Enhancing Anoxia Tolerance
[0754] 1. Background
[0755] The use of carbon dioxide (CO.sub.2) and hydrogen sulfide
(H.sub.2S) to enhance the survival of a complex metazoan,
Drosophila melanogaster, in anoxia was investigated. These
experiments indicated that these agents, especially H.sub.2S, can
increase the anoxia tolerance of adult D. melanogaster.
[0756] C. elegans embryos survive in anoxia (<10 ppm O.sub.2) by
entering into suspended animation, and development can proceed in
0.5% O.sub.2. However, there is a 10-fold range (0.01-0.1% O.sub.2)
of lethal oxygen concentrations. Moreover, preventing oxygen
utilization with carbon monoxide can prevent hypoxic damage in
embryos. Thus, if there is not enough oxygen available for
efficient biological activity, then it is better to not have (or
use) any oxygen.
[0757] In more complex metazoans, the cellular oxygen concentration
is not necessarily the same as the environmental oxygen levels. In
C. elegans, oxygen is delivered to the tissue by diffusion.
However, in higher organisms there are proteins that bind oxygen in
order to transport it to the tissues, such as hemoglobin.
Therefore, when environmental oxygen levels drop, there may be
residual oxygen at the cells.
[0758] Most organisms are not able to survive exposure to
environmental anoxia. One possibility is that the residual oxygen
at the cellular level is toxic, corresponding to the lethal oxygen
range observed in C. elegans embryos. In this scenario, survival of
anoxia would be enhanced if the residual oxygen was removed or made
un-utilizable. CO.sub.2 promotes the release of O.sub.2 from
hemoglobin and H.sub.2S is a potent inhibitor of oxidative
phosphorylation.
[0759] 2. Materials and Methods
[0760] Basic experimental setup. Adult flies were introduced into
35 mL tubes made of glass with a gas-tight rubber stopper (Balsh
tubes). This was usually accomplished by anesthetizing flies with
CO.sub.2, moving groups of flies to vials with food to recover for
at least 2 hours, and then transferring them into the Balsh tube.
To exchange the gaseous environment in the Balsh tube, two 18 gauge
needles were inserted into the rubber stopper, and gas is blown
into one of the needles at 100 mL/min. To prevent dessication,
gasses were humidified by bubbling through 10 mL of water before
passing it through the Balsch tube. The water in the bubbler is
equilibrated with the gas for at least 20 minutes before starting
the experiment.
[0761] For "stopped-flow" experiments, gas exchange proceeded for
60 minutes before sealing the tube. For "low-flow" experiments, gas
flow continued throughout the experiment. CO.sub.2 was from the
house source (100%), and anoxic environments were established by
flushing out room air with 100% nitrogen (N.sub.2). Care was taken
to prevent introduction of room air into the system while switching
the atmosphere from CO.sub.2 to N.sub.2.
[0762] After anoxic treatment, oxygen was reintroduced into the
Balsh tube by flushing with house air for 20 minutes. The rubber
stopper was then removed and a food vial is inverted over the top
of the Balsh tubes with Parafilm. Flies were scored as alive if
they resume movement. Viability was scored at least 18 hours after
the end of anoxic treatment. After two weeks, if the food vials
contained larvae and/or pupae the flies were considered to be
fertile.
[0763] 3. Results
[0764] Treatment with CO.sub.2 prior to anoxic exposure. Adult
flies exhibited a higher rate of anoxic survival if they are first
pretreated with CO.sub.2. After a 19 h anoxic exposure in a
stopped-flow experiment, adult flies pretreated with CO.sub.2 for
30 or 90 minutes exhibited 54% or 28% survival, respectively. No
survival was observed in controls exposed to anoxia without
CO.sub.2 pretreatment or CO.sub.2 without subsequent anoxic
exposure. Furthermore, no flies survived anoxic exposure with
CO.sub.2 pretreatment if they were also exposed to CO.sub.2
immediately following anoxic exposure for 20 minutes.
[0765] A short exposure to CO.sub.2 was sufficient for enhanced
survival of anoxia. In stopped-flow experiments with 22 h anoxic
exposure, the fraction of flies that survive was highest if
CO.sub.2 was administered for 0.5-5 minutes before switching to the
nitrogen atmosphere (FIG. 16). Thus, for subsequent experiments,
the standard protocol was to treat with CO.sub.2 for 10 minutes
before anoxic exposure. In a low-flow experiment using this
protocol, 6% of adult flies survived a 20 h anoxic exposure, and
this survival required the CO.sub.2 pretreatment.
[0766] Experiments suggested that it is important to prevent
reintroduction of O.sub.2 between the CO.sub.2 treatment and
establishing the N.sub.2 environment. When the water in the bubbler
used to humidify the air was not equilibrated with N.sub.2 before
flushing out the CO.sub.2, no flies survived a 13 h anoxic exposure
in these experiments, whether the N.sub.2 was introduced at 10, 50,
or 100 mL/min. Under these conditions, the CO.sub.2 atmosphere was
flushed out with a N.sub.2/O.sub.2 mix resulting from the O.sub.2
dissolved in the water.
[0767] A series of low-flow experiments were conducted to determine
the time of anoxic exposure that can be tolerated with CO.sub.2
exposure compared to no pretreatment, testing each condition in
duplicate (FIG. 17). In these data, the trend is that CO.sub.2
pretreatment results in greater survival. An important caveat is
that these experiments deviated from the standard protocol in that
the flies were anesthetized with CO.sub.2 and transferred to the
Balsh tubes and allowed to recover for only 10-20 minutes before
initiating the CO.sub.2 treatment (except for Trial 2 of the 18 h
timepoint).
[0768] Several other experiments were performed that were not
informative to whether pretreatment with CO.sub.2 was beneficial.
For instance, in one experiment no survival was observed after 17,
22, and 24 h of anoxia in a low-flow experiment with a 10 min
CO.sub.2 pretreatment period. However, in other experiments, many
flies survived after 17 h. This may indicate that in certain cases
other factors affect the outcome, such as age of the adults,
circadian rhythms or variations in room temperature. In another
experiment to compare the stopped-flow setup to the low-flow setup,
no flies survived a 17 or 19.5 h anoxic exposure; however, in this
instance mold contamination may have contributed to the demise of
the flies.
[0769] Treatment with H.sub.2S prior to anoxic exposure. Including
H.sub.2S in the pretreatment protocol more dramatically enhanced
the ability of adult flies to survive anoxia. In a series of
experiments analogous to those shown in FIG. 17, adding 50 ppm
H.sub.2S to the CO.sub.2 pretreatment (H.sub.2S/CO.sub.2) increased
the fraction of flies that survived treatment (FIG. 18). These
flies seem healthy, and produced progeny after exposure. However,
in a similar experiment no flies survived 18, 20, 25, or 30 h in
anoxia after 10 minutes in H.sub.2S/CO.sub.2. The cause of this
discrepancy is unclear. Consistent with a beneficial influence of
H.sub.2S treatment, after a 15 h anoxic exposure 50% of flies
pretreated with H.sub.2S survived, whereas there was no recovery of
control flies that were not exposed to H.sub.2S. In this
experiment, the flies were treated with CO.sub.2 for 10 min, then
H.sub.2S/CO.sub.2 for 10 min, then N.sub.2/H.sub.2S for 10 min, and
finally with N.sub.2 for the duration of the low-flow
experiment.
[0770] CO.sub.2 treatment is not required for the
H.sub.2S-dependent increase in survival of anoxia. 25% of flies
treated with 50 ppm H.sub.2S in room air prior to being made anoxic
for 18.5 h survived. The fraction of flies surviving was unaffected
if a 10 min exposure to H.sub.2S/CO.sub.2 was added before
establishing the anoxic environment. In a control experiment where
flies were treated only with CO for 10 min before the anoxic
exposure, only 11% of the flies recovered.
[0771] The time at which H.sub.2S is administered appears important
for enhancing anoxic survival. If H.sub.2S is present throughout
the anoxic exposure (20 h) no flies recover, whether H.sub.2S was
present during the CO.sub.2 pretreatment or not. However, 35% of
flies survive if 50 ppm H.sub.2S is present in the CO.sub.2
pretreatment and then is removed as the anoxic environment is
established. In parallel experiments, 6% of flies exposed to anoxia
after 10 min pretreatment with CO.sub.2 (no H.sub.2S) survived.
[0772] Preliminary experiments with larvae and embryos. The
enhanced survival of anoxia after treatment with CO and CO with HS
is also observed in embryos and larvae. After exposure to anoxia
for 24 h, 7 pupae were funned from a pool of 0-19 h old embryos.
However, 20 pupae were observed from a matched pool that was
pretreated with CO.sub.2 for 10 min. Similarly, larvae exposed to
24.5 h anoxia can resume movement upon reoxygenation only if they
were pretreated with CO.sub.2 or H.sub.2S/CO.sub.2. 0-24 h old
embryos survive 18.5 h anoxic exposure and develop to adulthood
whether pretreated with CO.sub.2 or H.sub.2S/CO.sub.2.
[0773] Cold treatment during anoxia. Decreasing the environmental
temperature may extend the length of time that adult flies can
survive anoxic exposure. At room temperature, no flies survived a
15.5 h anoxic exposure in a stopped-flow setup, but 20% of those
kept at 4.degree. C. while anoxic recovered. Similarly, no flies
survived being transitioned to anoxia at 4.degree. C. and then
moved to room temperature for 16.5 h. However, after 16.5 and even
40 h flies that were kept at 4.degree. C. during the entire
exposure recovered and were fertile. Pretreating with CO.sub.2
before establishing anoxic environment did not have a noticeable
difference in these experiments.
Example 8
Drop in Core Body Temperature
[0774] In both rats and mice, it was shown that using H.sub.2S and
CO.sub.2, metabolic output can be reduced, shown as reduced body
core temperature. FIG. 20A-B show that at time 0 when H.sub.2S or
CO.sub.2 are first applied, the body core temperature of the
animals begins to drop. Six hours later, when the H.sub.2S or
CO.sub.2 are removed, the temperature begins to return to normal.
It is clear that larger mammals require more H.sub.2S to affect
metabolism.
Prophetic Example 9
Gas Matrix
[0775] In order to determine the concentration of each component
gas in a custom mixed atmosphere that provides the greatest
capacity to control metabolic flexibility in mammals, the following
experiments can be performed. The gases include oxygen (O.sub.2),
nitrogen (N.sub.2), carbon dioxide (CO.sub.2), hydrogen sulfide
(H.sub.2S), and helium (He). While H.sub.2S probably reduces oxygen
demand in mitochondria, CO.sub.2 may further reduced oxygen demand.
In addition, it has been found that reduced body core temperature
is essential for reduced metabolism. Therefore, helium gas, with
its high heat capacity, may provide a simple and noninvasive
cooling method. Furthermore, using 100% O.sub.2, a normoxic 20.95%
oxygen can be maintained in any gas mix in which the other
constituents make up less than 79.05% of the total. And finally,
nitrogen is used to balance the mix to 100%.
[0776] These experiments describe a progressive approach to assay
the gases singly and in combination first in mouse then rat, then
dog. It is the goal with this gas matrix to develop a foundation on
which to work with multiple variables in a logical order. The
experimental design is depicted in FIG. 21.
[0777] One of the features of the gas matrix is that it makes clear
that experiments will only be performed if previous experiments
(linked by arrows) are complete. Mixing experiments will not be
performed in any animal model without first optimizing the
component gases. Furthermore, a gas or gas mix will not be used in
a rat without first optimizing the dose in mouse nor in a dog
without first optimizing in rat. Thus, it shows the progression of
experiments using single gases to multiple gas mixes (reading
top-right to bottom-left) and mice to rats to dogs (reading
top-left to bottom-right). Mice will always be used first to
determine the concentration of component gases that provide the
best control of metabolic flexibility. Once the most effective dose
of a gas is determined using mice, the same experiments will be
performed in rat. At the same time, the next gas or gas mix will be
assayed using mice. Once the concentration is determined in rat,
the gas will be tested in dogs. The following table provides a
slightly different way to view the gas matrix and defines the order
of experiments:
TABLE-US-00010 sequential order mouse rat dog 1 H.sub.2S + CO.sub.2
CO.sub.2 2 He/O2 H.sub.2S + CO.sub.2 CO.sub.2 3 H.sub.2S + CO.sub.2
+ He He/O2 H.sub.2S + CO.sub.2 4 H.sub.2S + CO.sub.2 + He He/O2 5
H.sub.2S + CO.sub.2 + He
[0778] Procedure 1. Carbon Dioxide (CO.sub.2)
[0779] Mice: It was found that 15% CO.sub.2 affords control of
metabolic flexibility in mice. However, given the limitations of
our mixing abilities, we were unable to test higher concentrations.
This is no longer true, and we can test CO.sub.2 concentrations up
to 80%. Therefore, we will begin at 15% CO.sub.2 and increase in 5%
increments to 40% then 10% increments to 80%. Animals will be
exposed for 6 hours. Mice will be exposed using a 375 ml glass
chamber in which the animals will be supplied with water and into
which a premixed gas atmosphere will be flowed at a rate of 500
milliliter per minute. These chambers will be contained in an
incubator so that ambient temperature can be controlled. This table
provides a framework for our high-concentration CO.sub.2
experiments but additional experiments may be required to better
understand the effects. Mice can be used in multiple experiments
but we will not use an animal more frequently than once per week.
Furthermore, animals can function as their own controls in
subsequent experiments.
TABLE-US-00011 % CO.sub.2 15 20 25 30 35 40 50 60 70 79 % O.sub.2
21 21 21 21 21 21 21 21 21 21 % N2 64 59 54 49 44 39 29 19 9 0
[0780] Metabolism (O.sub.2 consumption and body core temperature)
and activity will be monitored. At 15% CO.sub.2, tidal volume
increases but respiration rate remains unchanged. The mice do not
appear to "gasp". Increasing CO.sub.2 concentrations should
increase the narcotic effect.
[0781] These experiments will be performed in an incubator so that
we can then reduce ambient temperature to 10.degree. C. to assay
the relationship between body core temperature and metabolic
output.
[0782] Rats: Experiments in rats will begin using a 3% CO.sub.2 and
21% O.sub.2 balanced nitrogen environment. This is regarded as
normocapnia as it is the exhaled concentration of CO.sub.2. From 3%
we will increase in 2% increments to 15%. This increase can be
performed in a single baseline experiment where we increase the
CO.sub.2 concentration until we see a change in metabolism.
Metabolism will be monitored by measuring O.sub.2 consumption and
body core temperature. A single rat in one experiment can be used
to determine this minimal CO.sub.2 dose. In subsequent experiments,
where the effects of 6 hours of CO.sub.2 exposure will be assayed,
a single rat will be used for a single CO.sub.2 dose (i.e., the
level will not change during the experiment). Rats can be used in
multiple experiments; they will be used no more than one time in a
week. Rats will be exposed using a 2800 ml glass container in which
the animals will be supplied with water and into which premixed
gases will be flowed at a rate of 3 liters per minute. This table
shows the structure of the first CO.sub.2 experiments using rats
but others may be required to fully explore the effects.
TABLE-US-00012 % CO2 3 5 7 9 11 13 15 % O.sub.2 21 21 21 21 21 21
21 % N.sub.2 76 74 72 70 68 66 64
[0783] From 15% to 80% experiments will progress as was done using
mice (5% increments from 15%-40%, 10% increments from 40%-80%).
Metabolism and behavior will be monitored. Once the effective dose
of CO.sub.2 for the rats is determined, the ambient temperature
will be reduced to learn if metabolism is further reduced by
reduced body core temperature as it is using H.sub.2S. These
experiments will be performed in an incubator that will provide the
cooling at the beginning of and during the experiment as well as
the heat at the end of the experiment.
[0784] After completion of the rat CO.sub.2 studies, it will be
known if rats require more CO.sub.2 than mice to reduce their
metabolism (as is true for H.sub.2S), the same, or less.
Understanding of this key allometric trend will provide a better
hypothesis for the active CO.sub.2 dose in dogs.
[0785] The stopping points for these procedures in mice and rats
will be a drop in O.sub.2 consumption by 99% or a drop in CO.sub.2
production by 99%.
[0786] Dogs: The experimental design for the dogs will be the same
as that used for rats and mice (using a flow rate of 10
liters/minute). Experiments will begin using 3% CO.sub.2 and
increase until a physiological response is seen. Dogs will be
exposed to mixed gases using an anesthesia mask to which they have
been preconditioned before exposure. O.sub.2 consumption and body
core temperature will be monitored. The same one or two dogs can be
used for these experiments.
Procedure 2. Hydrogen Sulfide and Carbon Dioxide
(H.sub.2S+CO.sub.2)
[0787] By mixing H.sub.2S and CO.sub.2 we will look for synergistic
effects of the two gases. That is, can H.sub.2S and CO.sub.2 be
used together to reduce metabolism as profoundly as higher
concentrations of single gases. In the first experiments, using
mice, H.sub.2S at 20 ppm and titrated in CO.sub.2 to 15% (or other
concentration to be determined in procedure 1) will be used. A
single animal can be used to vary the concentration of CO.sub.2
while holding H.sub.2S constant. Second, we will use 40 ppm
H.sub.2S and add CO.sub.2 to 15%. Third, we will use 80 ppm
H.sub.2S and bring CO.sub.2 to 15%. A single animal can be used in
each of these experiments. O.sub.2 consumption, body core
temperature, and behavior will be monitored. The experiments listed
in the table(s) provide a foundation for exploring the effects of
the H.sub.2S+CO.sub.2 mix and other experiments will be necessary
to understand effects.
TABLE-US-00013 exp O.sub.2 % H.sub.2S ppm CO.sub.2 % 1 21 20
5-10-15 2 21 40 5-10-15 3 21 80 5-10-15
[0788] Once an effective mix is determined, ambient temperature
will be lowered to learn if the optimized gas mix synergizes with
lower body core temperature to further lower metabolic rate. In
these temperature dependent experiments, the concentrations of the
gases in the mix will not change. Once again, one animal can be
used in multiple experiments with no more than one experimental
procedure per animal per week.
[0789] The experiments using rats and dogs will be performed using
the same methodology. The CO.sub.2 concentrations for rat and dog
will be optimized in procedure 1 but it is hypothesized that they
will be between 5% and 15%. For dogs, the high H.sub.2S
concentration is greater than 400 ppm but has not yet been
determined.
Procedure 3 Helium (He)
[0790] Helium is an effective heat dissipator; its thermal
conductance is six times greater than nitrogen. It has been used in
many mammals including rats, dogs, and humans to promote cooling.
It is non toxic, inexpensive, and easy to handle. It is desirable
to use helium as others have in an 80%/20% mixture with oxygen
(He--O.sub.2) to enhance thermal conductivity via respiration. Five
preliminary experiments are proposed to analyze the effect of
He--O.sub.2 on metabolism and behavior. The standard 80%-20% mix
that is widely used will be employed. A mix containing 60% He will
also be tested to better reflect the minimum He--O.sub.2 mix we
will use in protocol 5 where we mix H.sub.2S, CO.sub.2 and He.
TABLE-US-00014 exp. animal temp He--O.sub.2--N2 1 mouse 23.degree.
C. 80-20-0 2 mouse 10.degree. C. 80-20-0 3 mouse 23.degree. C.
60-20-20 4 mouse 10.degree. C. 60-20-20 5 rat 23.degree. C. 80-20-0
6 rat 10.degree. C. 80-20-0 7 rat 23.degree. C. 60-20-20 8 rat
10.degree. C. 60-20-20 9 dog 23.degree. C. 80-20-0 10 dog
23.degree. C. 60-20-20
[0791] Oxygen consumption, carbon dioxide production, body core
temperature, and behavior will be monitored to learn if the same
effects that others have using He--O.sub.2 can be induced.
Procedure 4: Oxygen (O.sub.2)
[0792] That reduced oxygen concentration can reduce body core
temperature was shown by Gellhorn and Janus in 1936 using Guinea
pigs. It is desired to reproduce these experiments first in mice,
then in rats, and finally in dogs to learn if decreased O.sub.2
concentration decreases metabolism.
[0793] Mice: Experiments are proposed in which mice will be exposed
to decreasing concentrations of O.sub.2 down to 6%. Experiments
will progress in 5% increments. O.sub.2 consumption, CO.sub.2
production, body core temperature, and behavior will be assayed. If
convulsive behavior indicative of extreme hypoxia is observed,
O.sub.2 will be returned to 21%. The table below provides a general
outline of the O.sub.2 experiments. Exposure time is six hours in a
controlled chamber (with water) into which premixed gas is flowed.
Since there is evidence of hypoxic preconditioning, four separate
animals for these four experiments.
TABLE-US-00015 exp. % O2 % N2 1 21 79 2 16 84 3 11 89 4 6 94
[0794] Once the relationship between O.sub.2 tension and metabolism
has been determined, it may be important to repeat the experiments
in a cold environment. These experiments will be performed exactly
as the previous experiments except the temperature of the incubator
will be lowered to 10.degree. C.
[0795] Rats: It is desirable to conduct the same experiments using
rats that were performed previously with mice. If convulsive
behavior indicative of extreme hypoxia is observed, O.sub.2
concentration will be returned to 21%.
[0796] Dogs: If a positive correlation between reduced oxygen
tension and reduced metabolic rate is observed in mice and/or rats,
it will be desirable to perform the same series of experiments
using dogs.
Procedure 5: Hydrogen Sulfide, Carbon Dioxide, Helium, and Oxygen
(H.sub.2S+CO.sub.2+He+O.sub.2)
[0797] These experiments are the goal of the gas matrix; to
determine mix of O.sub.2, CO.sub.2, H.sub.2S, and He combined with
optimized ambient temperature that affords the most robust and
reversible control of metabolism. Therefore, using the
concentrations of the individual gases that were determined in the
previous procedures as a foundation, mixes of the four gases will
be assayed to find the one which affords the best control of
metabolic flexibility. O.sub.2, CO.sub.2, and H.sub.2S will be
varied relative to one another while helium will be used to balance
the mix. In the mouse experiments shown below, CO.sub.2 will be
varied while O.sub.2 and H.sub.2S will be held constant; helium
will be changed to maintain constant flow. We will use the same
metabolic assays including oxygen consumption and body core
temperature. A single animal can be used in multiple experiments.
Mice will be exposed for six hours. These experiments will then be
repeated using lower ambient temperature to learn how much reduced
body core temperature affects metabolism using the gas mix.
[0798] Mouse:
TABLE-US-00016 O.sub.2 H.sub.2S CO.sub.2 He exp. conc. % conc. ppm
conc. % balance 1 21 20 5-10-15 2 21 40 5-10-15 3 21 80 5-10-15 4
16 20 5-10-15 5 16 40 5-10-15 6 16 80 5-10-15 7 11 20 5-10-15 8 11
40 5-10-15 9 11 80 5-10-15 10 9 20 5-10-15 11 9 40 5-10-15 12 9 80
5-10-15 13 6 20 5-10-15 14 6 40 5-10-15 15 6 80 5-10-15
[0799] Rats: After it is learned what the optimal gas mixture is
for mice, experiments using rats will be done identical to those
performed using mice except the H.sub.2S concentrations are 100,
200, and 300 ppm. Rats will be treated for 6 hours.
[0800] Dogs: Experiments using dogs will be identical to those
using mice and rats. The concentrations will begin at 300 ppm and
go to a to-be-determined concentration. Single animal can be used
for multiple experiments but not more than once per week. Mice and
rats will be treated for 6 hours, dogs will be treated for two
hours.
Prophetic Example 10
Hydrogen Sulfide Dose Selection in Humans
[0801] Hydrogen sulfide can be administered to an animal or human
to induce stasis by any of a number of dosage forms and routes of
administration, including, but not limited to, inhalation of the
gaseous form or intravenous administration of a solution of
hydrogen sulfide. A method to determine the dosage form and route
of administration of hydrogen sulfide sufficient to induce stasis
in a whole organismin in need of stasis is described. A test
organism (e.g., a rat, dog, pig, monkey) is exposed to increasing
concentrations of hydrogen sulfide administered either as bolus
doses, intermittently, or continuously, and the physiological
state, including but not limited to, core body temperature, oxygen
consumption, carbon dioxide production, heart rate, blood pressure,
breathing rate, blood pH, movement, and wakefulness are monitored
while at various timepoints blood samples (0.5 mL) are removed.
Concentrations of hydrogen sulfide that are present in the test
animals' blood-derived plasma are measured using methods known in
the art, including, but not limited to X derivatization, Y
extraction, and quantitation using gas chromatography and mass
spectrometry.
[0802] Correlation of the steady state plasma levels of hydrogen
sulfide engendered by a particular dosing regimen in the test
animal with the achievement of stasis, to varying degrees, in the
test animal, defines an effective dose of hydrogen sulfide
sufficient to induce stasis in the test animal. The effective dose
for inducing stasis in a human in need of stasis is determined by
identifying the dose, route of administration, and dosing regimen
of hydrogen sulfide that achieves the same steady state plasma
concentrations of hydrogen sulfide in the humans as are achieved in
the test animals under conditions where stasis is induced. The
effective concentration of hydrogen sulfide to achieve stasis in a
human depends on the dosage form and route of administration. For
inhalation, in some embodiments effective concentrations are in the
range of 50 ppm to 500 ppm, delivered continuously. For intravenous
administration, in some embodiments effective concentrations are in
the range of 0.5 to 50 milligrams per kilogram of body weight
delivered continuously.
[0803] The range in each case is characterized by increasing
degrees of stasis achieved with increasing dose of the hydrogen
sulfide. A dose of hydrogen sulfide sufficient to cause a
sustained, 12-24 hour drop of three to five degrees Celsius to
32-34 degrees Celsius in the core body temperature of a human who
has suffered out-of-hospital cardiac arrest and who is unconscious
upon resuscitation and resumption of a heartbeat is predicted to
have a significant survival advantage over a similar human not
exposed to hydrogen sulfide, as described in Bernard et al.
2002.
Example 11
Animal Pre-Treatment Studies
[0804] The studies shown in Example 7 demonstrated that prior and
continuous treatment of male C57Bl/6 mice with H.sub.2S can enhance
their ability to survive under hypoxic conditions of 5% oxygen or
4% oxygen.
[0805] To determine the effect of H.sub.2S pre-treatment alone on
survivability under hypoxic conditions (without continuous H.sub.2S
exposure during hypoxia), mice were exposed to either 30 minutes of
room air (No PT) or 10 minutes of room air followed by 20 minutes
of 150 ppm H.sub.2S in room air (PT) before exposure to 5% O.sub.2
(5%), 4% O.sub.2 (4%), 1 hr 5% O.sub.2 followed by 4% O.sub.2 (4%+1
hr 5%), or 1 hr 5% O.sub.2 followed by 3% O.sub.2 (3%+1 hr 5%), and
their survival time determined. Experiments were stopped at 60
minutes, and animals still alive were returned to their cage. As
shown in FIG. 23, all of the mice in a cohort of animals
pre-exposed to 150 ppm H.sub.2S in room air for 20 minutes survived
subsequent exposure to 5% O.sub.2, while all of the control animals
exposed to room air alone had died within 15 minutes of exposure to
5% O.sub.2. Thus, pre-exposure of mice to H.sub.2S establishes a
physiological state in the mice that allows prolonged survival to
otherwise lethal hypoxia. The protection observed in H.sub.2S
pre-treated mice far exceeds the known protective effect of whole
body hypoxia preconditioning that has been reported in the
literature, in which survivability in 5% O.sub.2 was extended only
twofold (Zhang et al. 2004). Although not shown in FIG. 23, some
H.sub.2S pre-treated mice were able to survive for more than four
hours in 5% O.sub.2 and were able to recover with no noticeable
motor or behavioral deficits.
[0806] To determine if H.sub.2S pre-treatment enhances
survivability to even lower oxygen tensions, mice were exposed to
lower O.sub.2 concentrations. As shown in FIG. 24, H.sub.2S
pre-treatment greatly enhances survival in the presence of 5%
O.sub.2. In contrast, H.sub.2S pre-treatment provided only a small
increase in survival in the presence of 4% O.sub.2. However, if
H.sub.2S pre-treated mice were exposed to a step-wise reduction in
O.sub.2 levels, such that they were first pre-treated and then
exposed for 1 hour to 5% O.sub.2 and then exposed to either 4%
O.sub.2 or 3% O.sub.2, their survival time was enhanced to the same
level as that observed when they were exposed to 5% O.sub.2
following H.sub.2S pre-treatment (FIG. 28). Thus, pre-exposure to
H.sub.2S establishes a physiological state in which mice can
survive a graded reduction in oxygen tensions exceeding 80% (21%
normoxia reduced to 3% O.sub.2). Furthermore, in some experiments,
graded reduction of oxygen tension following H.sub.2S pre-treatment
showed the mice can survive for an hour in oxygen tensions as low
as 2.5%.
[0807] These data and those described in Example 7 demonstrate that
exposure to H.sub.2S has a pharmacological effect in which survival
in otherwise lethal hypoxia is greatly enhanced. In this context,
the pharmacological effects of H.sub.2S depend on dose levels and
duration of exposure to H.sub.2S, parameters that one skilled in
the art can vary to achieve optimum survivability to lethal
hypoxia. One skilled in the art will appreciate that the route of
administration (e.g., inhaled versus parenteral administration) can
also be varied to achieve the desired effect of lethal hypoxia
tolerance in a mammal. In addition, the pharmacological effect can
be observed either when H.sub.2S exposure is limited to
pre-treatment or is extended into the period of hypoxia. Likewise,
the timing of exposure to H.sub.2S relative to the onset of lethal
hypoxia can be varied to maximize the enhanced survivability. These
data are consistent with the hypothesis that reduction in oxygen
demand resulting from pretreatment with an active compound, such as
an oxygen antagonist, allows survival in reduced oxygen supply that
is otherwise lethal to the animal.
[0808] To characterize the changes in metabolism that occur in the
setting of enhanced survivability to lethal hypoxia afforded by
H.sub.2S treatment, CO.sub.2 production by the mice was measured
during exposure to H.sub.2S and thereafter following termination of
H.sub.2S treatment and subsequent exposure to 5% O.sub.2. The
change in CO.sub.2 production is shown in FIG. 25. Changes in
CO.sub.2 production upon transition to either 5% O.sub.2 or 4%
O.sub.2 were measured in mice exposed to either room air for 30
minutes (No PT) or room air for 10 minutes followed by 150 ppm
H.sub.2S for 20 minutes (PT). In addition, the change in CO.sub.2
production upon step-wise transition to 5% O.sub.2 for 1 hr
followed by 4% O.sub.2 was measured. The results of these
experiments are provided in FIG. 29.
[0809] CO.sub.2 production was reduced approximately two to
three-fold in the first five to ten minutes of H.sub.2S
pre-treatment, suggesting that stasis is induced in the mice during
the minute pre-treatment with 150 ppm H.sub.2S in room air.
However, O.sub.2 consumption and core body temperature of the
animals did not change significantly during the H.sub.2S
pre-treatment (data not shown), suggesting that a physiological
state other than stasis may be established in the mice during
exposure to H.sub.2S that allows enhanced survivability to lethal
hypoxia. Such a state might be characterized by a reduction in
metabolism within the biological material of a magnitude that is
less than that defined as stasis. In order to achieve stasis using
an active compound, the biological matter necessarily must
transition through a graded hypometabolic state in which oxygen
consumption and CO.sub.2 production are reduced less than twofold
in the biological matter. Such a continuum, in which metabolism or
cellular respiration is reduced by an active compound to a degree
less than twofold, is described as a state of "pre-stasis."
Continued monitoring of CO.sub.2 production following termination
of H.sub.2S pre-treatment and induction of lethal hypoxia shown in
FIG. 25 demonstrates an approximately 50-fold reduction in CO.sub.2
production, indicating that stasis is achieved during the exposure
to lethal hypoxia. A concomitant decrease in O.sub.2 consumption
and strong attenuation of motility in the mice during exposure to
lethal hypoxia further supports the observation that stasis is
subsequently achieved during exposure to lethal hypoxia.
[0810] Changes in CO.sub.2 production associated with transition to
hypoxic conditions of either 5% O.sub.2 or 4% O.sub.2 after
H.sub.2S pre-treatment or no pre-treatment were measured. As shown
in FIG. 28, mice exposed to either 5% O.sub.2 in the absence of
H.sub.2S pre-treatment or exposed to 4% O.sub.2 in the presence of
H.sub.2S pretreatment displayed a substantial decrease in CO.sub.2
production. In contrast, H.sub.2S pre-treated mice that were
subsequently exposed to either 5% O.sub.2 or 5% O.sub.2 followed by
4% O.sub.2 did not show any significant changes in CO.sub.2
production as compared to the new baseline level following H.sub.2S
pre-treatment. These results demonstrate a correlation between
reduced metabolic activity and death associated with exposure to 5%
O.sub.2 in the absence of H.sub.2S pre-treatment or exposure to 4%
O.sub.2 with H.sub.2S pre-treatment. In addition, these data
demonstrate that exposure to 5% O.sub.2 or a step-wise reduction
from 5% O.sub.2 to 4% O.sub.2 following H.sub.2S pre-treatment does
not result in an additional reduction in metabolic activity. To
summarize these results, decreases in CO.sub.2 evolution that occur
upon transition from normoxia to lethal hypoxia were blunted in
mice that were pre-treated with H.sub.2S. Transition from normoxia
to lethal hypoxia caused a 40% reduction in CO.sub.2 evolution, but
pre-treatment with H.sub.2S, while itself causing a 50-60%
reduction in CO.sub.2 evolution to a new, lower baseline, prevented
any further decrease in CO.sub.2 evolution on transition to lethal
hypoxia. These data demonstrate that H.sub.2S pretreatment alone
prevents additional reductions in metabolic activity typically
associated with a transition to lethal hypoxia, thereby enhancing
survival under hypoxic conditions. In addition, these data support
a model wherein pre-exposure of biological matter to active
compounds is sufficient to enhance survivability and/or reduce
damage from injuries or disease insults.
Example 12
Hydrogen Selenide Reduces Core Body Temperature in Mice at Reduced
Concentrations
[0811] It had been previously reported in the literature that
greater than 1 ppm of H.sub.2Se was lethal to animals. Experiments
were conducted according to the Materials and Methods discussed in
Example 4, except that H.sub.2Se was used at even lower
concentrations than with H.sub.2S. The H.sub.2Se used had an
initial concentration from the source tank of 20 ppm in nitrogen,
which was then diluted with room air to approximately 10 or 100
parts per billion (ppb). Animals were then exposed to this
mixture.
[0812] Two mice were exposed to 100 ppb H.sub.2Se for less than 10
minutes. FIG. 26 shows the drop in core body temperature and 3-fold
reduction in metabolic activity as evidenced by respiration in one
mouse.
[0813] The concentration of H.sub.2Se was reduced even further to
10 ppb. A mouse exposed to 10 ppb of H.sub.2Se also experienced a
reduction in core body temperature and respiration (FIG. 27).
[0814] Moreover, the effects of H.sub.2Se appear fully reversible
based on tests used to evaluate reversibility with H.sub.2S
(Blackstone et al., 2005, which is hereby incorporated by
reference).
Example 13
Hydrogen Sulfide Protects Against Lethal Hemorrhage
[0815] The studies shown in Examples 7 and 11 demonstrated that
treatment of mice with hydrogen sulfide (H.sub.2S) enhances their
ability to survive under hypoxic conditions of 5% oxygen or 4%
oxygen. To determine whether H.sub.2S treatment could also be used
to reduce morbidity and/or tissue damage associated with a more
clinically relevant acute injury model of ischemic hypoxia, rats
were treated with H.sub.2S during controlled lethal hemorrhage,
which reduces oxygen supply to tissues and results in death
(Blackstone et al., 2005). In this study, rats treated with
H.sub.2S survived lethal blood loss and fully recovered.
[0816] Rats were treated with H.sub.2S during controlled lethal
hemorrhage (60% blood loss). After surgical implantation of
catheters and recovery, blood was removed from conscious animals in
40 minutes. A small amount (300 ppm) of H.sub.2S mixed with room
air was administered to treated animals twenty minutes after the
beginning of the bleed (i.e., after 30% blood loss). Animals were
returned to room air without H.sub.2S at the end of the bleed.
Three hours after the end of the bleed, surviving animals were
given one shed-blood volume of lactated ringers solution
intravenously.
[0817] Most (6/7) of the H.sub.2S treated rats survived hemorrhage
and 3 hour shock period and recovered completely (Table 7). None of
these surviving rats exhibited behavioral or functional defects
after recovery. One H.sub.2S treated animal died 174 minutes after
the end of the bleed. All of the untreated animals died within 82
minutes after the end of the bleed; average survival time of
untreated animals was 35+/-26 minutes. Using a two-tailed Fishers
exact T-test, the p value is 0.0047.
[0818] In the first twenty minutes of bleeding (before 30% blood
loss) rats increased respiration rate and tidal volume to
compensate for decreased oxygen carrying capacity due to blood
loss. This increase in ventilation resulted in a decreased
respiratory carbon dioxide production (V.sub.CO2) (Table 7). After
60% blood loss, both H.sub.2S treated and untreated animals
exhibited decreased V.sub.CO2. Arterial blood lactate increased
while pCO.sub.2, bicarbonate ([HCO.sub.3.sup.-]), pH, and base
excess decreased (Table 7). Thus hemorrhage resulted in metabolic
acidosis with respiratory compensation. However, in H.sub.2S
treated rats, these changes were smaller in magnitude representing
a decrease in metabolic acidosis. Furthermore, in H.sub.2S treated
animals, V.sub.CO2 did not continue to decrease after hemorrhage.
In untreated animals, V.sub.CO2 decreased steadily until the
animals stopped breathing. H.sub.2S administration appears to
prevent the shock response from progressing to death
TABLE-US-00017 TABLE 7 Survival and physiology of a rat hemorrage
model using H.sub.2S H.sub.2S Treated Untreated Survival Complete
recovery 85.7% (6/7) 0% (0/7) Time to death of non-survivors (min)
174 (1/7) 35 +/- 26 CO.sub.2 production (V.sub.CO2) in ml/kg/min:
Pre-bleed 25 +/- 4 26 +/- 6 Mid-bleed 20 +/- 2 21 +/- 3 End of
bleed 16 +/- 2 11 +/- 3 15 minutes post bleed 17 +/- 3 7 +/- 5
Blood CO.sub.2 content (pCO.sub.2) in mmHg Pre-bleed 45 +/- 6 44
+/- 3 End of bleed 35 +/- 6 21 +/- 3 Blood bicarbonate content
([HCO.sub.3.sup.-]) in mmol/L Pre-bleed 32 +/- 3 30 +/- 1 End of
bleed 21 +/- 3 12 +/- 3 Blood pH Pre-bleed 7.46 +/- 0.03 7.45 +/-
0.02 End of bleed 7.41 +/- 0.02 7.35 +/- 0.06 Blood base excess in
mmol/L Pre-bleed 8 +/- 2 6 +/- 1 End of bleed -5 +/- 4 -14 +/- 3
Blood Lactate in mmol/L Pre-bleed 1.4 +/- 0.5 1.2 +/- 0.2 End of
bleed 6.6 +/- 1 11 +/- 3
Example 14
Benefit of Short-Term Exposure to Hydrogen Sulfide During
Hemorrhage
[0819] Male Sprague Dawley rats weighing 275-350 grams were
purchased from Charles River Laboratories one week before each
experiment and allowed to acclimate. On the day of the experiment,
catheters were surgically implanted into the right femoral artery
and vein. Catheters exited behind scapulae. Rats were administered
buprenorphine post-surgically and allowed to recover.
[0820] The anti-coagulant drug heparin (80-100 units) was
administered intravenously as a bolus to decrease the clotting
ability of the blood and enhance hemorrhage. Following heparin
administration, conscious unrestrained rats were placed
individually in a 2.75 liter crystallization dish with a glass lid.
Catheters, temperature probe, and gas sampling tube were passed
through a hole drilled in the middle of the lid. Temperature was
maintained at approximately isothermal temperature (27+/-2.degree.
C.).
[0821] The hemorrhage model was defined by the removal of 60% of
total body blood over the course of a 40 minute bleed. Blood was
removed using a peristaltic pump. To determine the amount of blood
that constitutes 60% of total body blood, rats were weighed and the
volume of blood to was calculated using the following equation
(0.06.times.body mass)+0.77 (Lee et al., (1985).
[0822] Treatment groups received exposure to either room air with
hydrogen sulfide (test animals), or room air containing nitrogen
(control animals) at a rate of 3 liters per minute administered by
a thermal mass flow controller (Sierra Instruments).
[0823] Hydrogen sulfide (H.sub.2S) (20,000 ppm balanced with
nitrogen) (Byrne Specialty Gas) was diluted into room air to a
concentration of 2000 ppm for treatment. Blood was removed at the
calculated rate via the femoral catheter artery. Blood was weighed
as it was removed. After twenty minutes (or at 50% of the 40 minute
bleed) the test animals were exposed to room air containing 2000
ppm hydrogen sulfide. The exposure was terminated when animals
exhibited apnea and dystonia. The average length of exposure to
hydrogen sulfide (H.sub.2S) was generally between 1 and 2 minutes.
The maximum concentration of H.sub.2S in the chamber was estimated
to be between 1000 and 1500 ppm. When the apnea and dystonia were
observed, the animals received exposure to room air. Test animals
resumed regular breathing patterns within 20 to 30 seconds upon
exposure. Control animals were bled at the same rate as the test
animals, but did not receive treatment with hydrogen sulfide.
Control animals did not exhibit apnea or dystonia during the course
of the experiment.
[0824] Metabolic rate was determined by measuring CO.sub.2
production (Licor Li7000). Temperature and CO.sub.2 data were
collected (ADI PowerLab). Arterial blood values were measured
(1-Stat blood chemistry analyzer). Following the bleed, animals
were placed in a cage for three hours and observed. At the end of
three hours, surviving rats were given lactated ringers ad libitum.
For non-surviving animals, time of death was declared when animals
stopped breathing and CO.sub.2 production ceased. After
resuscitation, rats were transferred to clean cages with food and
water and housed at 30.degree. C. for approximately 16 hours.
Catheters were surgically removed and animals were allowed to
recover for several hours at 30.degree. C. before transfer back to
the colony. Behavior and function tests were selected from a
battery of tests described in the SHIRPA protocol (Rogers et al.,
1997).
[0825] In these experiments, 7 out of 8 (88%) of the animals
treated with hydrogen sulfide (H2S) during the course of the
hemorrhage survived the hemorrhage. Two control animals who did not
receive treatment died during the three hour observation
period.
Example 15
Additional Results from Example 2
[0826] As discussed in Example 2 above, human foreskins were used
to evaluated the preservation of cells and tissue in carbon
monoxide. A total of eight human foreskins were ultimately
evaluated (Example 2 reports on three). The number of viable
keratinocytes was evaluated using trypan blue (Table 8 and FIG.
30). This showed that carbon monoxide exposure increased the number
of viable cells.
TABLE-US-00018 TABLE 8 Viability of keratinocytes isolated from
Foreskins exposed to either room air (RA) or CO for 24 hours were
tested for viability using trypan blue (tb) staining. CO RA
fraction live dead fraction live (tb-) dead (tb+) alive (tb-) (tb+)
alive 0 3 0.00 10 1 0.91 1 1 0.50 4 4 0.50 0 0 10 3 0.77 0 0 5 1
0.83 7 34 0.17 49 42 0.54 0 1 0.00 24 6 0.80 1 2 0.33 3 3 0.50 0 1
0.00 1 1 0.50 SUM 9 42 0.18 106 61 0.63 # cells recovered fraction
alive untreated 51 0.18 ttest 0.000883884 CO 167 0.63
Example 16
Low Level Chronic H.sub.2S Exposure Increases Survivability
[0827] Using methods and apparatus described in Example 1, C.
elegans nematodes were exposed to low levels of H.sub.2S (<100
ppm). Nematodes adapted to this treatment exhibit increased
lifespan and resistance to thermal stress, however, there is no
discernable decrease in metabolic activity as with induction of
stasis.
[0828] In nematodes, the inability to perform aerobic metabolism
(by reducing ambient oxygen concentration or addition of CO)
results in the induction of suspended animation, or stasis (see
Example 1). However, suspended animation was not induced by
exposing them to <100 ppm H.sub.2S in house air. At doses above
100 ppm, H.sub.2S can result in considerable lethality of the
population of nematodes exposed. Interestingly, even in conditions
where the majority of worms are killed by H.sub.2S, those that
survive appear normal and are not obviously harmed by the agent.
The worms growing in approximately 50 ppm H.sub.2S complete
embryogenesis, develop to sexual maturity and produce progeny at
the same rate as siblings raised in environments without H.sub.2S.
In contrast, in concentrations of oxygen where metabolic rate is
reduced (less than 3.5% O.sub.2), all of these processes are
slowed. Moreover, worms raised in H.sub.2S produce the same number
of progeny as controls in house air, suggesting that there are no
deleterious effects from these conditions. These data indicate that
H.sub.2S does not reduce metabolic activity under these conditions
in C. elegans.
[0829] Nematodes grown in H.sub.2S are more resistant to heat
stress than age-matched controls in house air alone (FIG. 31). In
this assay, worms raised in 50 ppm H.sub.2S were exposed to high
temperature in H.sub.2S and worms raised in house air were exposed
in house air. Thus, H.sub.2S-induced resistance to stress is not
correlated with decreased metabolic activity. However, this
resistance to heat-stress requires that the nematodes be adapted to
the H.sub.2S environment. Worms raised in house air and exposed to
heat-stress in H.sub.2S die more rapidly than if they were exposed
in house air. The adaptation to H.sub.2S is persistent, insofar as
worms raised in H.sub.2S and exposed to heat stress in house air
survive better than controls raised in house air. In addition,
worms adapted to a non-toxic low concentration of H.sub.2S (e.g.,
50 ppm) were resistant to higher concentrations of H.sub.2S that
are lethal to unadapted worms.
[0830] These data are consistent with data that flies transiently
exposed to H.sub.2S are subsequently able to survive anoxia better
than untreated controls (e.g., Example 7 and Example 11). The
protection against heat stress (in worms) and anoxic stress (in
flies) suggests that H.sub.2S may be able to increase survivability
in a variety of adverse or stressful states that may be encountered
clinically.
[0831] Worms adapted to 50 ppm H.sub.2S also have increased
lifespan compared to isogenic untreated controls (FIG. 32). This is
consistent with the idea that they are in a state that is generally
more resistant to various stresses associated with aging. In fact,
old worms grown in H.sub.2S seem more vigorous and healthy than
those of similar age not treated with H.sub.2S. Moreover, this is
also true when comparing worms from each population at the midpoint
of lifespan (i.e., the house air controls and H.sub.2S-treated
worms are not chronologically age matched, but the point where 50%
of each population has died). Thus, adaptation to H.sub.2S may slow
chronic cellular damage associated with aging in C. elegans.
Example 17
Implementation of Gas Matrix Experiments
[0832] Metabolic flexibility was evaluated in mice rats and dogs
using altered gas environments. Three parameters were used to
define this reduction in metabolism including changes in carbon
dioxide production, oxygen consumption measured by respirometry,
and core temperature as measured using telemetry. In experiments
with mice and rats the animals were placed into sealed chambers
with one gas import and one gas export. For dogs a mask was placed
over the snout of the animal with two hoses (import and export)
attached to the mask. The flow rate of gas for each of the animals
mice--500 cc per minute, rats--2 liters per minute, and dogs 40
liters per minute. Each atmosphere was constructed from compressed
gas by dilution into room air unless otherwise noted. For rat and
mouse experiments the ambient temperature was 7 to 10.degree. C.
during exposure to the test gases. For dogs ambient temperature was
room temperature (22.degree. C.).
TABLE-US-00019 TABLE 9 Description of gas environments constructed
to test for metabolic flexibility in mice rats and dogs. Mouse Rat
Dog Hydrogen sulfide Yes 0.01% Yes 0.03% No 0.85% Hydrogen selenide
Yes 0.0001% Yes 0.003% N/D Phosphine No 0.016% N/D N/D Carbon
dioxide Yes 15% Yes 15% No 9% H.sub.2S + CO.sub.2 Yes 0.01% + 15%
N/D N/D CO.sub.2 + low O.sub.2 Yes 15% + 8% Yes 15% + 8% N/D
CO.sub.2 + low O.sub.2 + He Yes 15% + 8% + 77% Yes 15% + 8% + 77%
Yes 9% + 15% + 77%
[0833] Table 9 shows the amount of each gas, which is given as a
percentage of the room air atmosphere unless otherwise noted.
Evidence of depression in metabolic rate of greater than 5-fold as
judged by carbon dioxide production or oxygen consumption during a
6-hour treatment is described by "Yes"; "No" (reduction or less
than a 5-fold reduction in these values is described as such; "N/D"
denotes experiments not done. The temperature drop in the dog
experiment (Carbon dioxide+low oxygen+Helium) was approximately
1.5.degree. C. over the course of 30 minutes of exposure. This drop
in temperature was considered significant because the dog was 12 kg
and no such temperature drop was seen during extensive baseline
recording of the animal in room air.
[0834] Animals exposed to various constructed atmospheres exhibited
metabolic flexibility as demonstrated by changes in core body
temperature (CBT) that approach ambient temperature (FIGS. 33-40).
FIG. 33 demonstrates a rat exposed to an atmosphere containing 15%
CO.sub.2, 8% O.sub.2, and 77% He has a metabolic depression that is
accelerated compared to a rat exposed to 300 ppm H.sub.2S under
similar conditions. FIG. 34 demonstrates a significant drop in CBT
of a mouse exposed to 1.2 ppm of H.sub.2Se. Rats exposed to room
air at an ambient temperature of 110.degree. C. do not show
significant drop in CBT (FIG. 35), nor do rats exposed to 80% He,
20% O.sub.2 at 7.degree. C. (FIG. 36). Rats exposed to an
atmosphere of 15% CO.sub.2, 20% O.sub.2, 65% He at an ambient
temperature of 7.degree. C. show significant drop in CBT (FIG. 37).
Similarly, FIG. 38 shows a significant CBT drop in a rat exposed to
an atmosphere of 15% CO.sub.2, 8% O.sub.2, 77% He at 7.degree. C. A
significant drop in CBT was also demonstrated in a dog exposed to
an atmosphere of 9% CO.sub.2, 20% O.sub.2, 71% He (FIG. 39). The
magnitude of the drop is lower, presumably because of the larger
size of the animal and the limitations of thermal diffusion. A
similar drop is seen in a dog exposed to different concentrations
of CO.sub.2.
Example 18
Screening of Compounds
[0835] A compound screen was performed to identify test compounds
capable of causing a reversible drop in subcutaneous temperature in
a mouse. Identified test compounds were then tested for their
ability to provide protection against lethal hypoxia (measured at
4% O.sub.2 as opposed to a typical environment of 21% O.sub.2
balanced nitrogen environment). The entire screening procedure
involved three steps:
[0836] 1) a primary (1.degree.) screen to determine the minimum
effective dose of a test compound that would produce a measurable
drop in a test mouse's subcutaneous temperature;
[0837] 2) a secondary (2.degree.) screen to determine the
reversibility of the temperature drop, as defined by the test mouse
having normal behavior 24 hours after treatment and having returned
to normal subcutaneous temperature in 24 hours or less; and
[0838] 3) atertiary (3.degree.) screen to assess the ability of the
test mouse to survive lethal hypoxia (4% O.sub.2) as compared to an
untreated control subject under identical hypoxic conditions.
[0839] The mice used in these studies were male C57BL/6 jugular
vein catheterized (JVC) mice, 5-6 weeks old (Taconic), which were
implanted dorsally with a subcutaneous RFID temperature sensor
(IPTT-300, Bio Medic Data Systems, Inc. (BMDS)) and allowed to
recover for at least 24 hours. The mice were dosed through the
in-dwelling catheter with the infusion of test compound using 1 or
5 ml Luer-Lok syringes (Becton Dickinson) and an infusion pump
(Harvard Apparatus). A DAS-6008 data acquisition module from BMDS
recorded subcutaneous temperature of the mouse via the transponder,
and this data was input into a computer spreadsheet and plotted
against time.
[0840] Primary (1.degree.) Screen:
[0841] For the primary screen, the infusion of test compound was
made up at a concentration that was considered to be the maximum
optimized concentration. The pH was adjusted with NaOH or HCl to
6-8, the osmolarity was adjusted with sodium chloride to 250-350
mOsm and the total dose of test compound to be administered (in mg)
divided by the test subject's weight (in kg) did not exceed 400% of
its published mg/kg LD50 in a mouse.
[0842] Mice were placed into a tall glass-bottom jar with opaque
walls and infused via the jugular vein. The test compound was
infused using a step protocol with increased infusion rates over 2
hours (Table 10).
TABLE-US-00020 TABLE 10 Test Compound Infusion Step Protocol
infusion time (min) rate .mu.L/min microliters infused microliters
infused total 0-20 0.8 15.875 15.875 20-40 1.6 31.75 47.625 40-60
3.2 63.5 111.125 60-80 6.3 127 238.125 80-100 12.7 254 492.125
100-120 25.4 508 1000.125
[0843] During the infusion, the mouse subcutaneous temperature was
read every 3-5 minutes, and any changes in the mouse behavior were
recorded. The results of the primary screen revealed whether the
test compound had the ability to lower subcutaneous temperature to
33.degree. C. or lower, and indicated the effective dose required
to lower subcutaneous temperature as measured by the infusion rate
of the test compound at which a steady temperature drop was first
observed.
[0844] Secondary (2.degree.) Screen:
[0845] Test compounds that produced a decrease in mouse
subcutaneous temperature to 33.degree. C. or below were tested in
the secondary screen. In the secondary screen, the mouse was
infused with test compound for 60 minutes at a rate of 50% of the
effective infusion rate determined in the primary screen. During
the infusion, the mouse subcutaneous temperature was monitored by
taking measurements every 3-5 minutes. If the subcutaneous
temperature did not decrease in the first 60 minutes, the infusion
rate was doubled and continued for another 60 minutes. When the
mouse subcutaneous temperature decreased to 33.degree. C. or below,
the infusion was immediately stopped, and the mouse recovery was
assessed by measuring subcutaneous temperature and observing the
mouse behavior. The mouse temperature and behavior were observed
and recorded 24 hours after treatment. The result of the secondary
screen determined if the test compound caused a reversible drop in
subcutaneous temperature without lethality.
[0846] Tertiary/lethal hypoxia (3.degree.) screen: In the tertiary
screen, the mouse was infused with test compound at the rate
determined in the secondary screen. The mouse subcutaneous
temperature was measured every 3-5 minutes until it decreased to
33.degree. C., as in the secondary screen. The infusion was stopped
and the mouse was immediately transferred to a hypoxic chamber (4%
O.sub.2), together with a control mouse, either infused with
vehicle (salt solution, 148 mM, osmolarity=300), or untreated. The
closed glass chamber was perfused with air and nitrogen at a
continuous flow to achieve the desired hypoxic atmosphere of 4%
O.sub.2. If the mouse survived 60 minutes in the hypoxic
atmosphere, it was transferred back to room air, and its recovery
was monitored for 24 hours by recording the subcutaneous
temperature and by behavioral observation.
[0847] The control mouse typically died within 6-15 minutes.
[0848] Mice infused with either sodium sulfide (effective dose 0.79
mmol/kg), sodium thiomethoxide (effective dose 4.61 mmol/kg), or
sodium thiocyanate (effective dose 4.67 mmol/kg) survived exposure
to lethal hypoxia for 60 minutes. A mouse infused with cysteamine
(effective dose 7.58 mmol/kg) survived in lethal hypoxia for 45
minutes; a mouse infused with cysteamine-S-phosphate sodium salt
survived in lethal hypoxia for 31 minutes; and a mouse infused with
tetrahydrothiopyran-4-ol survived in lethal hypoxia for 15 minutes.
These survival rates are compared to the survival rate of a control
mouse, which typically died within 6-15 minutes in the hypoxic
environment.
[0849] In comparison, certain other test compounds identified in
the primary screen as having the ability to lower body temperature
did not protect from lethal hypoxia. Thioacetic acid, selenourea,
and phosphorothioic acid S-(2-((3-aminopropyl)amino)ethyl) ester
all reduced body temperature, but did not enhance survival in
hypoxia. 2-mercapto-ethanol, thioglycolic acid, and 2-mercaptoethyl
ether all reduced body temperature but were toxic at the effective
temperature reducing dose. Thiourea, dimethyl sulfide, sodium
selenide, sodium methane sulfinate, N-acetyl-L-cysteine did not
reduce subcutaneous temperature at the highest doses given in this
study. Dimethylsulfoxide was excluded because the effective dose
(10% DMSO) was too high to be considered for pharmaceutical
purposes.
[0850] These studies establish that the screening procedures
developed may be successfully used to identify compounds capable of
protecting animals subjected to lethal hypoxia. In addition, the
results of this studies indicate that the identified compounds, as
well as other compounds to be identified using this procedure, may
be used to protect patients from injury resulting from hypoxic and
ischemic injury.
Example 19
Daily Exposure to Active Compound
[0851] The ability to adapt physiologically to extended treatment
with hydrogen sulfide (H.sub.2S) and the time required for
adaptation was tested in a mouse. Adaptation was defined as a
failure to exhibit a decrease in core body temperature (greater
than 4.degree. C.) when an animal was exposed to 80 ppm of hydrogen
sulfide in room air for an extended treatment. Extended treatment
was defined as exposure to 80 ppm of hydrogen sulfide in room air
for four hours per day, four days per week for six weeks.
[0852] The mice used in these studies were male C57BL/6 mice or
male C129 mice, 5-6 weeks old. Telemetry devices were implanted
into the coelomic cavity of the mice prior to the experiments to
record core temperature.
[0853] Mice (eight per treatment) were exposed to hydrogen sulfide
in a single plexiglass box with separate chambers for each mouse at
a flow rate was 10 liters per minute. Detection of carbon dioxide
production and oxygen consumption animals in 500 cc glass bowls had
flow rate of 0.5 liters per minute.
[0854] Mice adapted to hydrogen sulfide exposure on average, in a
one week period. Adaptation was defined by a failure to exhibit a
decrease (greater than 4.degree. C.) in core temperature when
animals were exposed to 80 ppm of hydrogen sulfide in room air for
4 hours. Mice that did not exhibit a drop in core temperature were
deemed to have a physiological adaptation to hydrogen sulfide. Mice
treated with hydrogen sulfide that developed an adaptation showed
an increase in oxygen consumption (vO2) compared to carbon dioxide
production (vCO2) when compared to untreated control mice (FIG.
42). Mice with an adaptation to H.sub.2S showed a lower Respiratory
Quotient (RQ ratio), defined as the ratio of vCO2/vO2 or a
comparison of produced carbon dioxide to consumed oxygen (FIG.
43).
Example 20
Applications for Thalassemia
[0855] Based on the current results in other model systems
presented here, it expected the red blood cells of animals with the
hematological disorder, thalassemia, will have an increased ability
to withstand oxidative damage, leading to prolonged red cell
survival when they are treated with sulfides. The following
experiments will be performed to confirm that treatment with active
compounds can protect animals with thalassemia from oxidate
damage.
[0856] In a first series of experiments, animals with thalssemia
will be treated by chronic exposure to an active compound. After
initial tests to establish baselines, treatment will be initiated
following the protocol summarized below. If erythropoiesis or red
cell survival are improved, an effect may be observed in as early
as 1-2 weeks, since the half-life of thalassemic red cells is
estimated at 4-7 days. We will review a smear and obtain a
reticulocyte count at two weeks, and initiate more extensive
studies after an additional two weeks. If an improvement in the red
blood cells is determined in mice, as identified by an improved
reticulocyte count and blood smear, the study will continue until a
plateau is observed in the metrics used in the monthly studies.
This study has a projected final end point of one year. At one
year, red cell survival studies will be completed, and the animals
will be sacrificed. If no improvement is observed, exposure will
continue for up to one additional year, when survival studies will
be accomplished and the animals sacrificed.
[0857] Protocol 1:
[0858] 1) Animals will undergo initial studies.
[0859] 2) Within one week after initial studies, animals will be
housed identically and either: [0860] A) exposed to 80 ppm H.sub.2S
for 8 hours/day; [0861] B) no exposure; or [0862] C) given water
with 0.25% dimethyl sulfide (DMSO) and allowed to drink ad lib
(estimates from prior studies suggest mice will consume 5-10
cc/day/mouse with 2.5-25 microgram/day DMSO content. Using an
average weight of 18 g per mouse, consumption is estimated to be
700-1,400 ug/kg/day).
[0863] In a second series of experiments, the effect of in utero
treatment with an active compound will be determined, following the
protocol summarized below.
[0864] Protocol 2:
[0865] 1) Plugged dams will be treated in one of the following
groups three days post conception: [0866] A) exposed to 80 ppm
H.sub.2S for 8 hours/day; [0867] B) no exposure; or [0868] C) Given
water with 0.25% dimethyl sulfide (DMSO) and allowed to drink ad
lib (estimates from prior studies suggest mice will consume 5-10
cc/day/mouse with 2.5-25 microgram/day DMSO content. Using an
average weight of 18 g per mouse, consumption is estimated to be
700-1,400 ug/kg/day).
[0869] 2) Plugged dams will be allowed to give birth naturally, and
pups will be genotyped and sacrificed for detailed analysis soon
after birth.
[0870] The test animals will be monitored throughout these studies
as indicated below.
[0871] Monitoring:
[0872] 1) Initial studies: [0873] 1. reticulocyte count; [0874] 2.
blood smea;r [0875] 3. Computed Tomography (CT scan) of spleen and
bones; [0876] 4. O.sub.2 consumption and CO.sub.2 production;
[0877] 5. weight; [0878] 6. sulfide metabolites and [0879] 7.
hematocrit (60 .mu.l blood total).
[0880] 2) At two weeks: reticulocyte count and blood smear (5 .mu.l
blood).
[0881] 3) Monthly studies: [0882] 1. reticulocyte count; [0883] 2.
CT of spleen and bones; [0884] 3. O.sub.2 consumption and CO.sub.2
production; [0885] 4. weight; and [0886] 5. sulfide metabolites
(blood draw will be less than 30 .mu.l).
[0887] 4) One month prior to sacrifice: red cell survival
studies.
[0888] 5) Sacrifice and detailed in vitro analysis.
Example 21
Applications for Sickle Cell Anemia
[0889] To test this hypothesis, a mouse model of sickle cell
disease (SCD) will be used in which the strain was engineered so
that it no longer expresses mouse Hba and Hbb, but does express
human HBA and HBB (Patsy, et al, 1997). It mimics the genetic,
hematologic and histopathologic features that are found in humans
afflicted with sickle cell anemia, including irreversibly sickled
red blood cells, anemia and multiorgan pathology. A significant
percentage of sickle cell mice do not survive to adulthood.
[0890] Using this mouse model, various agents and sulfide
containing compounds will be tested for efficacy against SCD.
Exposures will be acute and chronic, and animals will be exposed
either at birth or in utero. Viability to birth for pups exposed in
utero or to adulthood will be one endpoint to measure efficacy.
Phenotypic effects will be evaluated through reticulocyte count,
hematocrit and red blood cell (RBC) half-life measurements (which
are normally 20 fold less for SCD compared to wild type
controls).
Example 21
Cyanide Exposure Experiment
[0891] This example shows that when mice are exposed to 80 ppm of
cyanide in room air they gradually reduce their core temperature to
about 34.degree. C.
[0892] One goal of these metabolic flexibility studies has been the
identification of compounds that can reduce oxygen consumption and
protect animals from hypoxic injury. Previously, it was
demonstrated that Hydrogen Sulfide (H.sub.2S), a potent inhibitor
of oxygen consumption, can reduce metabolism and protect mice and
rats from hypoxic injuries. Hydrogen Cyanide (HCN) is similar to
H.sub.2S in many ways and we would like to use our assays of
metabolic output to learn if it can be used to regulate metabolism.
Like H.sub.2S, HCN is widely used in industrial chemical syntheses
and it is found in many biological systems including humans. It is
not known if HCN is merely a byproduct of carbon-nitrogen
metabolism or if it possesses specific biological activities. Like
H2S, HCN is thought to act by reacting with transition metal
containing proteins such as oxidases and dehydrogenases. HCN is not
strongly reactive with components of hemoglobin.
[0893] In humans, the NIOSH IDLH (immediately dangerous to life and
health) value is 50 ppm. The OSHA PEL (permissible exposure limit)
TWA (time weighted average for 8 hours) is 10 ppm. The LC50 for rat
is 143 ppm for 60 minutes.
[0894] To measure metabolic effects of HCN, mice were exposed to
increasing concentrations of HCN starting at 1 ppm. Oxygen
(O.sub.2) consumption, carbon dioxide (CO2) production, body core
temperature (BCT) and behavior were measured or evaluated. The
concentration of HCN was raised by 10 ppm increments until an
effect on metabolism was observed or when the animals appeared to
show signs of distress. A metabolic effect is defined as a 10%
change in less than 10 minutes in any of the assay values described
above.
[0895] It was found that when mice were exposed to 80 ppm of
cyanide in room air at room temperature they gradually reduced
their core temperature to about 34.degree. C. This is distinct from
the decrease seen with 80 ppm hydrogen sulfide where the core
temperature drops to approximately 28 degrees C. In addition, there
was a very slow recovery of the core temperature in mice exposed to
cyanide (approximately 14 hours) compared to hydrogen sulfide
(approximately 2 hours).
[0896] The hypothesis was tested that the slow recovery, as judged
by core temperature, in cyanide could be rescued by brief exposure
to 80 ppm hydrogen sulfide. This was based on the idea that, a
conserved enzyme, rhodanese (and other similar enzymes), might use
hydrogen sulfide and cyanide to produce the relatively less toxic
agent, thiocyanate. Already it has been shown that rhodanese can
use cyanide and thiosulfate to produce thiocyanate. (Chen 1933)
Furthermore, intravenous administration of thiosulfate is the
standard of care for treating cyanide intoxication in the US. It
was found that the time to recover the core temperature following
exposure to cyanide was reduced by brief treatment with hydrogen
sulfide. This result suggests that hydrogen sulfide exposure might
be used to treat conditions in which patients suffer from cyanide
intoxication.
[0897] All of the compositions and methods disclosed and claimed
herein can be made and executed without undue experimentation in
light of the present disclosure. While the compositions and methods
of this invention have been described in terms of preferred
embodiments, it will be apparent to those of skill in the art that
variations may be applied to the compositions and methods, and in
the steps or in the sequence of steps of the methods described
herein without departing from the concept, spirit and scope of the
invention. More specifically, it will be apparent that certain
agents which are both chemically and physiologically related may be
substituted for the agents described herein while the same or
similar results would be achieved. All such similar substitutes and
modifications apparent to those skilled in the art are deemed to be
within the spirit, scope and concept of the invention as defined by
the appended claims.
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