U.S. patent application number 12/996244 was filed with the patent office on 2011-06-30 for unacylated ghrelin and analogs as therapeutic agents for vascular remodeling in diabetic patients and treatment of cardiovascular disease.
This patent application is currently assigned to ALIZE PHARMA SAS. Invention is credited to Maria Felice Brizzi, Ezio Ghigo, Giampiero Muccioli.
Application Number | 20110160121 12/996244 |
Document ID | / |
Family ID | 41078180 |
Filed Date | 2011-06-30 |
United States Patent
Application |
20110160121 |
Kind Code |
A1 |
Brizzi; Maria Felice ; et
al. |
June 30, 2011 |
UNACYLATED GHRELIN AND ANALOGS AS THERAPEUTIC AGENTS FOR VASCULAR
REMODELING IN DIABETIC PATIENTS AND TREATMENT OF CARDIOVASCULAR
DISEASE
Abstract
The present invention relates to a method for treating a
cardiovascular disease, for increasing the number of circulating
angiogenic cells (CAC) and/or improving the function of CAC and a
method for improving vascular remodeling and/or neovascularisation.
The method comprises administering to the subject a therapeutically
effective amount of unacylated ghrelin or a polypeptide comprising
the amino acid sequence set forth in SEQ ID NO: 1 or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1; and
to pharmaceutical compositions comprising unacylated ghrelin or a
polypeptide comprising the amino acid sequence set forth in SEQ ID
NO: 1 or a fragment or analog thereof having the biological
activity of SEQ ID NO: 1.
Inventors: |
Brizzi; Maria Felice;
(Turin, IT) ; Muccioli; Giampiero; (Turin, IT)
; Ghigo; Ezio; (Turin, IT) |
Assignee: |
ALIZE PHARMA SAS
Ecully
FR
|
Family ID: |
41078180 |
Appl. No.: |
12/996244 |
Filed: |
June 12, 2009 |
PCT Filed: |
June 12, 2009 |
PCT NO: |
PCT/EP09/57263 |
371 Date: |
March 10, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61061163 |
Jun 13, 2008 |
|
|
|
Current U.S.
Class: |
514/1.9 ;
514/16.4; 514/21.7; 514/21.8; 514/9.7 |
Current CPC
Class: |
A61P 3/00 20180101; A61P
17/02 20180101; A61P 3/04 20180101; A61P 9/00 20180101; A61P 17/00
20180101; A61P 3/10 20180101; A61P 43/00 20180101; A61P 37/06
20180101; A61K 38/25 20130101; A61P 9/10 20180101 |
Class at
Publication: |
514/1.9 ;
514/9.7; 514/21.8; 514/21.7; 514/16.4 |
International
Class: |
A61K 38/22 20060101
A61K038/22; A61P 9/10 20060101 A61P009/10; A61K 38/08 20060101
A61K038/08; A61P 9/00 20060101 A61P009/00; A61P 17/02 20060101
A61P017/02; A61P 43/00 20060101 A61P043/00 |
Claims
1. A method for treating a cardiovascular disease in a subject,
comprising administering to the subject a therapeutically effective
amount of a polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1 or a fragment or analog thereof having the
biological activity of SEQ ID NO: 1.
2. The method of claim 1, wherein the method is for improving
vascular remodeling and/or neovascularization.
3. The method of claim 1, wherein the method is for increasing the
number of circulating angiogenic cells (CAC) and/or improving the
function of CAC.
4. (canceled)
5. The method of claim 3, wherein the method is for improving CAC
mobilization.
6. The method of claim 3, wherein the method is for reducing CAC
senescence.
7. The method of claim 1, wherein the polypeptide is administered
in a dose varying from about 0.001 .mu.g/kg to about 10 mg/kg.
8. The method of claim 1, wherein the cardiovascular disease is
associated with type I or type II diabetes.
9. (canceled)
10. (canceled)
11. The method of claim 1, wherein the cardiovascular disease is
associated with atherosclerotic vascular degeneration.
12. The method of claim 1, wherein the fragment thereof comprises
amino acid residues selected from the group consisting of amino
acid residues 8 to 12 of SEQ ID NO: 1 or an analog thereof and
amino acid residues 6 to 13 of SEQ ID NO: 1 or an analog
thereof.
13. (canceled)
14. The method of claim 1, wherein the fragment thereof has an
amino acid sequence selected from the group consisting of SEQ ID
NO: 6, SEQ ID NO: 7, SEQ ID NO: 8 and analogs thereof.
15. The method claim 1, wherein the fragment thereof consists of
amino acid sequence SEQ ID NO: 6.
16. (canceled)
17. A method for increasing the number of circulating angiogenic
cells (CAC) and/or improving the function of CAC in a subject,
comprising administering to the subject a therapeutically effective
amount of a polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof having the
biological activity of SEQ ID NO: 1.
18. (canceled)
19. The method of claim 17, wherein the method is for improving CAC
mobilization.
20. The method of claim 17, wherein the method is for reducing CAC
senescence.
21. (canceled)
22. The method of claim 17, wherein the subject is at risk of
having or has a cardiovascular disease.
23. The method of claim 17, wherein the subject has type I or type
II diabetes.
24. The method of claim 17, wherein the polypeptide is administered
in a dose varying from about 0.001 .mu.g/kg to about 10 mg/kg.
25. The method of claim 17, wherein the fragment thereof comprises
residues 8 to 12 of SEQ ID NO: 1 or an analog thereof.
26. The method of claim 17, wherein the fragment thereof comprises
residues 6 to 13 of SEQ ID NO: 1 or an analog thereof.
27. (canceled)
28. The method claim 17, wherein the fragment thereof consists of
amino acid sequence SEQ ID NO: 6.
29. A method for improving vascular remodeling and/or
neovascularization in a subject comprising administering to the
subject a therapeutically effective amount of a polypeptide
comprising the sequence set forth in SEQ ID NO: 1, or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1.
30. The method of claim 29, wherein the method is for increasing
the number of circulating angiogenic cells (CAC) and/or improving
the function of CAC.
31. (canceled)
32. The method of claim 29, wherein the fragment thereof comprises
amino acid residues selected from the group consisting of amino
acid residues 8 to 12 of SEQ ID NO: 1 or an analog thereof and
amino acid residues 6 to 13 of SEQ ID NO: 1 or an analog
thereof.
33-44. (canceled)
45. The method of claim 29, for improving wound healing in the
subject.
46. The method of claim 29, for treating a venous or a diabetic
ulcer in the subject.
47. The method of claim 29, for improving engraftment associated
with organ transplantation.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and priority to U.S.
provisional application No. 61/061,163 filed Jun. 13, 2008, the
content of which is herein incorporated by reference.
FIELD OF THE INVENTION
[0002] This invention relates to vascular remodeling and to the
treatment of vascular diseases, to methods and pharmaceutical
compositions for treating a cardiovascular disease, methods and
pharmaceutical compositions for increasing the number of
circulating angiogenic cells (CAC) and/or improving the function of
CAC, and methods and pharmaceutical compositions for improving
vascular remodelling and/or neovascularisation.
BACKGROUND ART
[0003] Ghrelin (AG) is a 28 amino acid peptide, purified and
identified from rat stomach, and characterized by the presence of
an n-octanoyl modification on the Ser.sup.3 residue (Ref. 1). AG is
the endogenous ligand of the growth hormone secretagogue receptor
(GHSR) (Refs. 2, 3) and in addition to growth-hormone-releasing
properties, AG is also detected in the cardiovascular system
including in the heart, vasculature and endothelial cells of large
vessels, indicating that it may also influence vascular biology,
vascular physiology, and atherogenesis (Refs. 4, 5, 6).
[0004] Des-acyl ghrelin (or unacylated ghrelin, UAG), the
unacylated form of ghrelin, whose concentration in plasma and
tissue is higher, compared to AG, fails to bind GHSR-1a and is
devoid of any central activity (Ref. 7). However, UAG shares with
AG many biological activities and common binding sites on several
peripheral tissues. AG and UAG exhibit similar GHS-R independent
biological activities, including a cytoprotective effect (Ref. 9)
and an effect on adipogenesis in vivo (Ref. 10). In most, but not
all, of the cells where UAG activity was evaluated, GHSR-1a is not
expressed, suggesting that such pleiotropic activities shared with
AG may be mediated by a yet unidentified receptor distinct from
GHSR-1a.
[0005] It has been demonstrated that UAG is a biologically active
peptide, particularly at the metabolic level, having notably been
shown to exert anti-diabetogenic effects as described in U.S. Pat.
No. 7,485,620, in U.S. patent application publication number U.S.
20080159991, in U.S. patent application publication number U.S.
20080312133 and in WO/2008/145749.
[0006] It was previously generally reported that AG and UAG act
directly on cardiomyocytes to inhibit experimentally-induced cell
death through activation of a survival signaling pathway (Ref. 8).
AG was also shown to inhibit basal and TNF-.alpha.-induced
chemotactic cytokine production and mononuclear cell adhesion in
human umbilical vein endothelial cells (HUVECs)(Ref. 5). It was
further reported that treatment of human microvascular endothelial
cells (HMVECs) with exogenous AG significantly increased cell
proliferation, migration, in vitro angiogenesis and ERK2
phosphorylation in these cells (Ref. 4). Recently, Kleinz et al.
(Ref. 35) demonstrated that AG and UAG play a role in the paracrine
regulation of vascular tone in humans; more specifically they
showed that AG and UAG have vasodilator actions in human
arteries.
[0007] Accelerated vascular disease is the major cause of death and
disability in patients with diabetes. Endothelial injury is thought
to represent a crucial step in initiation and progression of
atherosclerotic vascular disease in diabetes setting (Ref. 11).
[0008] It was previously reported that advanced glycated end
products (AGEs) contribute to impaired vascular remodeling in the
diabetic setting (Ref. 12). The formation of AGEs and the
production of reactive oxygen species (ROS), as a cellular response
to AGE in diabetes, seem to mainly contribute to these events.
[0009] Vascular remodeling does not rely exclusively on
proliferation of resident endothelial cells but also involves
circulating endothelial progenitor cells (EPC). Recent data
demonstrated that in patients with cardiovascular risk factors such
as, but not limited to, patients with diabetes, the number of EPC
is reduced and their function impaired (Refs. 13, 14, 15).
[0010] Two types of EPC have so far been described, the early and
late EPC. Although they share common features, they have some
distinct features with respect to morphology, proliferative
potential, and in vitro functional characteristics. Unlike late
EPC, early EPC do not adopt a typical endothelial phenotype in
vitro but enhance neovascularization in an indirect paracrine
fashion in vivo. This led to redefining these cells as circulating
angiogenic cells (CAC). CAC, that are monocyte-like cells, may home
from the bone-marrow into sites of neovascularization, participate
in re-endothelization after vascular injury and differentiate into
mature endothelial cells in situ (Ref. 16).
[0011] Compelling evidence indicates that as the cardiovascular
risk factor profile increases, CAC number decreases and CAC
functional activity is impaired, thus limiting CAC delivery to, for
example, sites of ischemia where angiogenesis could be
required.
[0012] Treatment with certain cytokines induces bone-marrow (BM)
mobilization of CAC which, in turn, likely protects against
cardiovascular risk (Refs. 17, 18).
[0013] Oxidative stress plays a major role in vascular tissue
damage and endothelial injury associated with diabetes. Mainly, the
production of ROS in this setting is induced by advanced glycated
end products (AGEs), notably produced from CAC.
[0014] There is an important need to design a way to improve
vascular remodeling and neovascularization in patients at risk of
suffering from a cardiovascular disease or suffering from a
cardiovascular disease in order to prevent or to treat
cardiovascular diseases. One solution is to increase CAC cell
number and/or improve CAC functionality, which can be achieved by,
improving their mobilization from the bone marrow, decreasing ROS
production induced by AGEs, decreasing CAC senescence or apoptosis
rate, and by enhancing CAC capacity to differentiate into an
arterial or a venous phenotype (i.e., to form vessels in vivo).
[0015] The earlier observations that AG may have an effect on
vascular dysfunction and cardio-protection led to evaluate the in
vitro and in vivo effect of UAG on same, as well as to evaluate the
effect of UAG on CAC biology, which notably, has not been
demonstrated before.
SUMMARY OF THE INVENTION
[0016] According to one aspect, the present invention relates to a
method for treating a cardiovascular disease in a subject,
comprising administering to the subject a therapeutically effective
amount of a polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1 or a fragment or analog thereof having the
biological activity of SEQ ID NO: 1.
[0017] According to another aspect, the present invention relates
to a method for increasing the number of circulating angiogenic
cells (CAC) and/or improving the function of CAC in a subject,
comprising administering to the subject a therapeutically effective
amount of a polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof having the
biological activity of SEQ ID NO: 1.
[0018] According to another aspect, the present invention relates
to a method for improving vascular remodeling and/or
neovascularization in a subject comprising administering to the
subject a therapeutically effective amount of a polypeptide
comprising the sequence set forth in SEQ ID NO: 1, or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1.
[0019] According to another aspect, the present invention relates
to a pharmaceutical composition for use in the treatment of a
cardiovascular disease, comprising a therapeutically effective
amount of a polypeptide, wherein the polypeptide comprises the
amino acid sequence set forth in SEQ ID NO: 1, or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1,
together with a pharmaceutically acceptable carrier.
[0020] According to another aspect, the present invention relates
to an isolated polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof having the
biological activity of SEQ ID NO: 1, for increasing the number of
circulating angiogenic cells (CAC) and/or improving the function of
CAC in a subject.
[0021] According to another aspect, the present invention relates
to an isolated polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof, for
improving vascular remodeling and/or neovascularization in a
subject.
[0022] According to another aspect, the present invention relates
to an isolated polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof, for
improving wound healing in a subject.
[0023] According to another aspect, the present invention relates
to an isolated polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof, for
improving engraftment associated with transplantation.
[0024] According to another aspect, the present invention relates
to an isolated polypeptide comprising the amino acid sequence set
forth in SEQ ID NO: 1, or a fragment or analog thereof, for use in
tissue engineering.
[0025] According to another aspect, the present invention relates
to the use of a therapeutically effective amount of a polypeptide
comprising the amino acid sequence set forth in SEQ ID NO: 1 or a
fragment or analog thereof having the biological activity of SEQ ID
NO: 1, in the preparation of a medicament for the treatment of a
cardiovascular disease in a subject.
[0026] According to another aspect, the present invention relates
to the use of a therapeutically effective amount of a polypeptide
comprising the amino acid sequence set forth in SEQ ID NO: 1, or a
fragment or analog thereof having the biological activity of SEQ ID
NO: 1 for increasing the number of circulating angiogenic cells
(CAC) and/or improving the function of CAC in a subject.
[0027] According to another aspect, the present invention relates
to the use of a therapeutically effective amount of a polypeptide
comprising the amino acid sequence set forth in SEQ ID NO: 1, or a
fragment or analog thereof having the biological activity of SEQ ID
NO: 1 in the preparation of a medicament for increasing the number
of circulating angiogenic cells (CAC) and/or improving the function
of CAC in a subject.
[0028] According to another aspect, the present invention relates
to the use of a therapeutically effective amount of a polypeptide
comprising the sequence set forth in SEQ ID NO: 1, or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1 for
improving vascular remodeling and/or neovascularization in a
subject.
[0029] According to another aspect, the present invention relates
to the use of a therapeutically effective amount of a polypeptide
comprising the sequence set forth in SEQ ID NO: 1, or a fragment or
analog thereof having the biological activity of SEQ ID NO: 1 in
the preparation of a medicament for improving vascular remodeling
and/or neovascularization in a subject.
BRIEF DESCRIPTION OF THE FIGURES
[0030] FIGS. 1A to 1F illustrate the protective effect of UAG on
CAC from diabetes-associated oxidative stress. In FIG. 1A, the
percentage of CAC in S phase was evaluated by FACS analysis. In
FIGS. 1B to 1F, ROS production from CAC was measured over the
indicated periods of time. FIGS. 1E and 1F illustrate that UAG
(6-13), a fragment of UAG, also has a protective effect on CAC from
diabetes-associated oxidative stress.
[0031] FIGS. 2A to 2E illustrate that UAG prevents CAC senescence.
In FIG. 2A, the senescence was evaluated by acidic .beta.-gal
activity on cultured CAC with AGE, UAG and AGE+UAG. In FIG. 2B,
AGE-, UAG- and AGE+UAG-cultured CAC were assayed by Western
blotting using the indicated antibodies. In FIG. 2C, CAC were
transfected with p53 siRNA or with the scrambled sequence. In FIG.
2D, CAC from age- and sex-matched diabetic patients treated with
saline or UAG were evaluated for acidic .beta.-gal activity. In
FIG. 2E, CAC recovered from diabetic patients treated as above were
assayed by Western blotting using the indicated antibodies.
[0032] FIGS. 3A to 3D illustrate induction by UAG of CAC
mobilization and arterial specification. In FIG. 3A, a
representative FACS analysis of CAC recovered from type 2 diabetic
patients analyzed for the expression of CD45, CD14, CD146 and
CD105. In FIG. 3B, CAC recovered after saline or UAG or AG
treatment from healthy donors (N) and diabetic patients (D) were
counted. In FIG. 3C, the percentage of cells in the S phase was
evaluated on CAC from diabetic patients (D) or healthy subjects
(N), treated with UAG, AG or with saline. In FIG. 3D, Q-RT-PCR was
performed on CAC cells from type 2 diabetic patients or healthy
donors cultured as above. The indicated arterial and venous markers
were evaluated.
[0033] FIGS. 4A to 4F illustrate that UAG induces CAC mobilization
in diabetic mice and CAC exposed to UAG act as angiogenic cells. In
FIG. 4A, a representative FACS analysis of CAC recovered from
diabetic mice (NOD/SCID and ob/ob) or from wt mice analyzed for the
expression of CD45, CD31, CD33 and KDR is reported. In FIG. 4B,
blood, drawn from NOD/SCID, ob/ob and wt mice, after UAG or saline
treatment was analyzed. In FIG. 4C, the percentage of cells in S
phase was evaluated by FACS analysis on CAC obtained from different
mouse models, treated or not with UAG. In FIG. 4D, a Q-RT-PCR was
performed on CAC from mouse models cultured as above. The indicated
arterial and venous markers were evaluated. In FIG. 4E, an
immunohistochemical analysis of Matrigel plugs containing IL-3 and
labelled CAC, recovered after implantation into SCID mice. Panel a
(left) corresponds to CAC recovered after saline treatment, panel b
(right) after UAG treatment. The ability of CAC to form functional
vessels is reported in panel a. Black arrows indicate positive CAC
cells. In FIG. 4F, Matrigel plugs recovered indicate that the
majority of vessels are lined by human HLA Class I positive cells.
The number of human or host derived vessels is reported in the
histogram.
[0034] FIGS. 5A and 5B illustrate that UAG (UAG (1-28)) and UAG
(6-13) fragment have binding sites on CAC membranes.
DETAILED DESCRIPTION
[0035] For ease of reference, the following abbreviations and
designations are used throughout:
AG ghrelin or acylated ghrelin UAG unacylated ghrelin or Des-acyl
ghrelin UAG (6-13) unacylated ghrelin having residues 6 to 13 of
SEQ ID NO: 1 GHSR growth hormone secretagogue receptor CAC
circulating angiogenic cells EPC endothelial progenitor cells AGE
advanced-glycated end product BM bone-marrow VEGF vascular
endothelial growth factor FACS fluorescent-activated cell sorting
ROS reactive oxygen species.
[0036] An impairment of vascular remodeling has been described in a
diabetic setting (Refs. 32, 33). Both in patients with type 1 or
type 2 diabetes, the number of EPC is reduced and their functional
capability impaired (Refs. 15, 32). Adverse metabolic stress
factors seem to mainly contribute to the impaired functional
activity and to the reduced CAC recruitment into sites of arterial
injury (Refs. 15, 34).
[0037] The induction of vascular growth represents an attractive
therapeutic strategy in several pathological conditions. The
finding that cardiovascular risk factors, such as diabetes or
obesity, reduce the availability of EPC, restricts the ability to
treat with cell therapy patients who theoretically need it
most.
[0038] The invention defined herein provides evidence that UAG can,
inter alia, prevent metabolic stress factors and restore CAC number
and functional activity as shown by the ability of UAG-treated
cells to form vessels in vivo.
[0039] The present invention relates to the unexpected discovery of
the effects of UAG on CAC. More particularly, it relates to the
unexpected discovery that UAG mobilizes CAC, protects CAC from
oxidative stress or from diabetes-associated oxidative stress,
reduces CAC accelerated onset of senescence and restores CAC
functional activity, increases CAC number, prevents ROS production
in CAC both in physiological conditions and in diabetes setting,
binds to CAC and/or rescues functional impairment of CAC.
[0040] Thus, this study provides evidence that UAG can be used as a
novel therapeutic strategy to improve or ameliorate impaired
vascular remodeling in a subject or patient with cardiovascular
risk, or to treat a subject or a patient with a cardiovascular
disease or an ischemic disease, to increase CAC number and improve
CAC function, to improve engraftment, to improve engraftment
associated with or following transplantation of, for example, an
organ or part thereof, to be used in or to facilitate in vitro or
ex vivo tissue engineering, such as, but not limited to, blood
vessels engineering, to improve wound healing, to improve wound
healing in diabetic patients, such as diabetic patients suffering
from diabetic ulcers.
[0041] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
skill in the art to which the invention pertains.
Unacylated Ghrelin, Fragments and Analogs Thereof
[0042] For the purpose of the present invention the following terms
are defined below. In the present application, the terms "ghrelin"
and "acylated ghrelin" or "AG" are used interchangeably and have
the same meaning.
[0043] The term "unacylated ghrelin" or "UAG" is intended to mean
peptides that have the amino acid sequence specified in SEQ ID NO:
1
(1-NH.sub.2Gly-Ser-Ser-Phe-Leu-Ser-Pro-Glu-His-Gln-Arg-Val-Gln-Gln-Arg-Ly-
s-Glu-Ser-Lys-Lys-Pro-Pro-Ala-Lys-Leu-Gln-Pro-Arg-28; SEQ ID NO:
1). UAG may also be referred to as UAG (1-28).
[0044] Naturally-occurring variations of unacylated ghrelin include
peptides that contain substitutions, additions or deletions of one
or more amino acids which result due to discrete changes in the
nucleotide sequence of the encoding ghrelin gene or alleles thereof
or due to alternative splicing of the transcribed RNA. It is
understood that the said changes do not substantially affect the
properties, pharmacological and biological characteristics of
unacylated ghrelin variants. Those peptides may be in the form of
salts. Particularly the acidic functions of the molecule may be
replaced by a salt derivative thereof such as, but not limited to,
a trifluoroacetate salt.
[0045] By "peptide", "polypeptide" or "protein" is meant any chain
of amino acids, regardless of length or post-translational
modification (e.g., glycosylation or phosphorylation), or chemical
modification, or those containing unnatural or unusual amino acids
such as D-Tyr, ornithine, amino-adipic acid. The terms are used
interchangeably in the present application.
[0046] The term "fragments" or "fragments thereof" refers to amino
acid fragments of a peptide such as unacylated ghrelin. Fragments
of unacylated ghrelin are shorter than 28 amino acid residues.
Fragments of unacylated ghrelin may therefore be 27, 26, 25, 24,
23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6,
5 or 4 amino acid residues in length. For example, fragments of UAG
may have
residues 1-14 of SEQ ID NO: 1 as shown in SEQ ID NO: 2 ((UAG 1-14);
Gly-Ser-Ser-Phe-Leu-Ser-Pro-Glu-His-Gln-Arg-Val-Gln-Gln); residues
1-18 of SEQ ID NO: 1 as shown in SEQ ID NO: 3 ((UAG 1-18);
Gly-Ser-Ser-Phe-Leu-Ser-Pro-Glu-His-Gln-Arg-Val-Gln-Gln-Arg-Lys-Glu-Ser);
residues 1-5 of SEQ ID NO: 1 as shown in SEQ ID NO: 4 ((UAG 1-5);
Gly-Ser-Ser-Phe-Leu); residues 17-28 of SEQ ID NO: 1 as shown in
SEQ ID NO: 5 ((UAG 17-28);
Glu-Ser-Lys-Lys-Pro-Pro-Ala-Lys-Leu-Gln-Pro-Arg); residues 6-13 of
SEQ ID NO: 1 as shown in SEQ ID NO: 6 ((UAG 6-13);
Ser-Pro-Glu-His-Gln-Arg-Val-Gln); residues 8-13 of SEQ ID NO: 1 as
shown in SEQ ID NO: 7 ((UAG 8-13); Glu-His-Gln-Arg-Val-Gln) or
residues 8-12 of SEQ ID NO: 1 as shown in SEQ ID NO: 8 ((UAG 8-12);
Glu-His-Gln-Arg-Val) or analogs thereof.
[0047] Any other fragments of UAG that preserve the biological
activity of UAG are encompassed by the present invention. Some UAG
fragments have been reported in U.S. patent application serial
publication number US 20080312133 and in WO/2008/145749.
[0048] In some aspects of the invention, the polypeptides are used
in a form that is "purified", "isolated" or "substantially pure".
The polypeptides are "purified", "isolated" or "substantially pure"
when they are separated from the components that naturally
accompany them. Typically, a compound is substantially pure when it
is at least 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%,
or 99%, by weight, of the total material in a sample.
[0049] The term "analog of unacylated ghrelin", "analog of
fragments of unacylated ghrelin" or "analogs thereof" refers to
both structural and functional analogs of unacylated ghrelin or
fragments thereof which are, inter alia, capable of replacing UAG
in the biological function of UAG as described in the present
application, such as, but not limited to, in the prevention and
treatment of cardiovascular diseases, in protecting CAC cells from
oxidative stress or from diabetes-associated oxidative stress,
promoting vascular remodeling and neovascularization, increasing
CAC number, improving CAC function, protecting CAC from oxidative
stress, preventing ROS production in CAC both in physiological
conditions and in diabetes setting, protecting against oxidative
stress associated with inhibition of the accelerated onset of CAC
senescence, binding to CAC membranes, and increase mobilization of
CAC and/or rescue functional impairment of CAC, as described in the
present application. Hence such structural and functional analogues
will be useful for realizing therapeutic benefits in medical
conditions as described in the present application.
[0050] Simple structural analogs comprise peptides showing homology
with unacylated ghrelin as set forth in SEQ ID NO: 1 or homology
with any fragment thereof. An example of an analog of ghrelin is an
isoform of ghrelin-28 (SEQ ID NO: 1), des Gln-14 Ghrelin (a 27
amino acid peptide possessing serine 3 modification by n-octanoic
acid) which is shown to be present in stomach. It is functionally
identical to ghrelin in that it binds to GHSR-1a with similar
binding affinity, elicits Ca.sup.2+ fluxes in cloned cells and
induces GH secretion with similar potency as Ghrelin-28. It is
expected that UAG also has a des Gln-14 UAG that is functionally
identical to UAG.
[0051] Preferred analogs of UAG and preferred analogs of fragments
of UAG are those that vary from the native UAG sequence or from the
native UAG fragment sequence by conservative amino acid
substitutions; i.e., those that substitute a residue with another
of like characteristics. Typical substitutions include those among
Ala, Val, Leu and Ile; among Ser and Thr; among the acidic residues
Asp and Glu; among Asn and Gln; among the basic residues Lys and
Arg; and among the aromatic residues Phe and Tyr. Particularly
preferred are analogs in which several, for example, but not
limited to, 5-10, 1-5, or 1-2 amino acids are substituted, deleted,
or added in any combination. For example, the analogs of UAG may
differ in sequence from UAG by 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10
amino acid substitutions (preferably conservative substitutions),
deletions, or additions, or combinations thereof.
[0052] There are provided herein, analogs of the peptides of the
invention that have at least 50%, 55%, 60%, 65%, 70%, 75%, 80%,
85%, 90%, 95%, 96%, 97%, 98% or 99% sequence homology with the
amino acid sequences described herein over its full length, and
sharing at least one of the metabolic effects or biological
activity of UAG. A person skilled in the art would readily identify
an analog sequence of unacylated ghrelin or an analog sequence of a
fragment of unacylated ghrelin.
[0053] Analogs of UAG or analogs of fragments thereof are, for
example, analogs obtained by alanine scans, by substitution with
D-amino acids or with synthetic amino acids or by cyclization of
the peptide. Analogs of UAG or fragments thereof may comprise a
non-naturally encoded amino acid, wherein the non-naturally
encoding amino acid refers to an amino acid that is not one of the
common amino acids or pyrrolysine or selenocysteine, or an amino
acid that occur by modification (e.g. post-translational
modification) of naturally encoded amino acid (including, but not
limited to, the 20 common amino acids or pyrrolysine and
selenocysteine) but are not themselves incorporated into a growing
polypeptide chain by the translation complex. Examples of such
non-naturally-occurring amino acids include, but are not limited
to, N-acetylglucosaminyl-L-serine, N-acetylglucosaminyl-L-threonine
and O-phosphotyrosine.
[0054] As used herein, the term "modified" refers to any changes
made to a given polypeptide, such as changes to the length of the
polypeptide, the amino acid sequence, chemical structure,
co-translational modification, or post-translational modification
of a polypeptide.
[0055] The term "post-translational modification" refers to any
modification of a natural or non-natural amino acid that occurs to
such an amino acid after it has been incorporated into a
polypeptide chain. The term encompasses, by way of example only,
co-translational in vivo modifications, co-translational in vitro
modifications (such as in cell-free translation system),
post-translational in vivo modifications, and post-translational in
vitro modifications. Examples of post-translational modifications
are, but are not limited to, glycosylation, acetylation, acylation,
amidation, carboxylation, phosphorylation, addition of salts,
amides or esters, in particular C-terminal esters, and N-acyl
derivatives of the peptides of the invention. The types of
post-translational modifications are well known.
[0056] Certain peptides according to the present invention may also
be in cyclized form, such that the N- or C-termini are linked
head-to-tail either directly, or through the insertion of a linker
moiety, such moiety itself generally comprises one or more amino
acid residues as required to join the backbone in such a manner as
to avoid altering the three-dimensional structure of the peptide
with respect to the non-cyclized form. Such peptide derivatives may
have improved stability and bioavailability relative to the
non-cyclized peptides.
[0057] Methods for cyclising peptides are well known in the art and
for example may be accomplished by disulfide bond formation between
two side chain functional groups, amide or ester bond formation
between one side chain functional group and the backbone
.alpha.-amino or carboxyl function, amide or ester bond formation
between two side chain functional groups, or amide bond formation
between the backbone .alpha.-amino and carboxyl functions. These
cyclisation reactions have been traditionally carried out at high
dilution in solution. Cyclisation is commonly accomplished while
the peptide is attached to the resin. One of the most common ways
of synthesising cyclic peptides on a solid support is by attaching
the side chain of an amino acid to the resin. Using appropriate
protection strategies, the C- and N-termini can be selectively
deprotected and cyclised on the resin after chain assembly. This
strategy is widely used, and is compatible with either
tert-butyloxycarbonyl (Boc) or 9-fluorenylmethoxycarbonyl (Fmoc)
protocols. However, it is restricted to peptides that contain
appropriate side chain functionality to attach to the solid
support. A number of approaches may be used to achieve efficient
synthesis of cyclic peptides. One procedure for synthesising cyclic
peptides is based on cyclisation with simultaneous cleavage from
the resin. After an appropriate peptide sequence is assembled by
solid phase synthesis on the resin or a linear sequence is appended
to resin, the deprotected amino group can react with its anchoring
active linkage to produce protected cyclic peptides. In general, a
final deprotection step is required to yield the target cyclic
peptide.
[0058] Lactamazation, a form of cyclisation, may be performed to
form a lactam bridge using Fmoc synthesis, amino acids with
different protecting groups at the lateral chains may be
introduced, such as, but not limited to, aspartic acid (or
glutamic) protected with allyl ester at the beta ester (or gamma
ester for glutamic acid) and lysine protected with allyloxy
carbamate at the N-.epsilon.. At the end of the synthesis, with the
N-terminus of the peptide protected with Fmoc, Boc or other
protecting group different from Alloc, the allyl and alloc
protecting groups of aspartic acid and lysine may be deprotected
with, for example, palladium (0) followed by cyclization using
PyAOP (7-Azabenzotriazol-1-yloxytris(pyrrolidino)
phosphonium-hexafluorophosphate) to produce the lactam bridge.
[0059] Unless otherwise indicated, an amino acid named herein
refers to the L-form. Well recognised abbreviations in the art will
be used to describe amino acids, including levoratory amino acids
(L-amino acids or L or L-form) and dextrorotary amino acids
(D-amino acids or D or D-form), Alanine (Ala or A), Arginine (Arg
or R), Asparagine (Asn or N), Aspartic acid (Asp or D), Cysteine
(Cys or C), Glutamic acid (Glu or E), Glutamine (Gln or Q), Glycine
(Gly or G), Histidine (His or H), Isoleucine (Ile or I), Leucine
(Leu or L), Lysine (Lys or K), Methionine (Met or M), Phenylalanine
(Phe or F), Proline (Pro or P), Serine (Ser or S), Threonine (Thr
or T), Tryptophan (Trp or W), Tyrosine (Tyr or Y) and Valine (Val
or V). An L-amino acid residue within the native peptide sequence
may be altered to any one of the 20 L-amino acids commonly found in
proteins or any one of the corresponding D-amino acids, rare amino
acids, such as, but not limited to, 4-hydroxyproline or
hydroxylysine, or a non-protein amino acid, such as P-alanine or
homoserine.
[0060] UAG peptides may also be part of a fusion protein. It is
often advantageous to include an additional amino acid sequence
which contains secretory or leader sequences, pro-sequences,
sequences which aid in purification such as multiple histidine
residues, or an additional sequence for stability during
recombinant production.
[0061] Any other analogs of UAG or fragments thereof or any other
modified UAG or fragments thereof that preserve the biological
activity of UAG are encompassed by the present invention.
[0062] General methods and synthetic strategies used in providing
functional and structural analogs of UAG or fragments thereof are
commonly used and well known in the art and are described in
publications such as: "Peptide synthesis protocols" ed, M. W.
Pennigton & B. M. Dunn. Methods in Molecular Biology. Vol 35.
Humana Press, NJ., 1994; "Solid phase peptide synthesis" by Stewart
and Young, W. h Freeman & Co., San Francisco, 1969 and Erickson
and Merrifield; and "The Proteins" Vol. 2, p. 255 et seq. (Ed.
Neurath and Hill), Academic Press, New York, 1976.
[0063] As used herein, the term "homology" refers to sequence
similarity between two peptides while retaining an equivalent
biological activity. Homology can be determined by comparing each
position in the aligned sequences. A degree of homology between
amino acid sequences is a function of the number of identical or
matching amino acids at positions shared by the sequences so that a
"homologous sequence" refers to a sequence sharing homology and an
equivalent function or biological activity. Assessment of percent
homology is known by those of skill in the art.
[0064] Methods to determine homology, identity and similarity of
peptides are codified in publicly available computer programs.
Preferred computer program methods to determine identity and
similarity between two sequences include, but are not limited to,
the GCG program package, BLASTP, BLASTN, and FASTA. The BLAST X
program is publicly available from NCBI and other sources. The well
known Smith Waterman algorithm may also be used to determine
identity.
[0065] Preferred parameters for polypeptide sequence comparison
include the following:
Algorithm: Needleman and Wunsch, J. Mol. Biol. 48: 443-453 (1970);
Comparison matrix: BLOSSUM62 from Hentikoff and Hentikoff, Proc.
Natl. Acad. Sci. USA. 89:10915-10919 (1992);
Gap Penalty: 12; Gap Length Penalty: 4.
[0066] A program useful with these parameters is publicly available
as the "gap" program from Genetics Computer Group, Madison, Wis.
The aforementioned parameters are the default parameters for amino
acid sequence comparisons (along with no penalty for end gaps).
[0067] The polypeptides of the invention may be prepared in any
suitable manner as known in the art. Such polypeptides include
isolated naturally occurring polypeptides, recombinantly produced
polypeptides, synthetically produced polypeptides, or polypeptides
produced by a combination of these methods. Means and methods for
preparing such polypeptides are well known in the art.
[0068] Certain aspects of the invention use UAG polynucleotides.
These include isolated polynucleotides which encode the UAG
polypeptides, fragments and analogs defined in the application.
[0069] As used herein, the term "polynucleotide" refers to a
molecule comprised of a plurality of deoxyribonucleotides or
nucleoside subunits. The linkage between the nucleoside subunits
can be provided by phosphates, phosphonates, phosphoramidates,
phosphorothioates, or the like, or by nonphosphate groups as are
known in the art, such as peptoid-type linkages utilized in peptide
nucleic acids (PNAs). The linking groups can be chiral or achiral.
The oligonucleotides or polynucleotides can range in length from 2
nucleoside subunits to hundreds or thousands of nucleoside
subunits. While oligonucleotides are preferably 5 to 100 subunits
in length, and more preferably, 5 to 60 subunits in length, the
length of polynucleotides can be much greater (e.g., up to 100).
The polynucleotide may be any of DNA and RNA. The DNA may be in any
form of genomic DNA, a genomic DNA library, cDNA derived from a
cell or tissue, and synthetic DNA. Moreover, the present invention
may, in certain aspects, use vectors which include bacteriophage,
plasmid, cosmid, or phagemid.
[0070] The phrases "biological activity" or "biological property",
or the term "activity" in reference to the polypeptides of the
present invention, are used interchangeably herein and refer to the
pharmacological, biological or cellular abilities of the
polypeptides of the invention and include, but are not limited to,
the capacity of replacing UAG in the biological functions of UAG
such as but not limited to, in the prevention and/or the treatment
of cardiovascular diseases, in protecting CAC cells from oxidative
stress or from diabetes-associated oxidative stress, in promoting
vascular remodeling and neovascularization, in increasing CAC
number, in improving CAC function, in protecting CAC from oxidative
stress, in preventing ROS production in CAC both in physiological
conditions and in diabetes setting, in protecting against oxidative
stress associated with inhibition of the accelerated onset of CAC
senescence, in binding to CAC membranes, and in increasing
mobilization of CAC and/or rescuing functional impairment of
CAC.
Therapeutic Uses and Treatments
[0071] In one aspect, the present invention provides a method for
treating subjects such as patients at risk of having or having a
cardiovascular disease or an ischemic disease. The present
invention also provides a method for improving vascular remodeling
and/or neovascularization in a subject. In a further aspect, the
present invention provides a method for increasing the number of
CAC and improving the function of CAC in a subject. The present
invention also provides for a method to improve engraftment, more
particularly to improve engraftment associated with or following a
transplantation of, for example, a tissue or an organ or any part
thereof. The present invention also provides for a method to
improve wound healing, to improve engraftment and/or to facilitate
tissue engineering.
[0072] As used herein, the term "treatment" refers to both
therapeutic treatments as well as to prophylactic and preventative
measures. Those in need of treatment include those already with the
disease or disorder or condition as well as those in which the
disease, disorder or condition is to be prevented. Those in need of
treatment are also those in which the disorder, disease or
condition has occurred and left after-effects or scars. Treatment
also refers to administering a therapeutic substance effective to
improve or ameliorate symptoms associated with a disease, a
disorder or a condition to lessen the severity of or cure the
disease, disorder or condition, or to prevent the disease, disorder
or condition from occurring.
[0073] In one aspect, the method of the invention includes the step
of administering to a subject a therapeutically effective amount of
a polypeptide defined herein which shares the same potential
therapeutic indication as UAG itself. Such polypeptide comprises
the amino acid sequence set forth in SEQ ID NO: 1, or any fragments
or any analogs thereof as described above, such as, but not limited
to, UAG (6-13), UAG (8-12) and UAG (8-13) fragments.
[0074] Subjects that would benefit from being administered with the
polypeptides of the invention include, but are not limited to,
those that are at risk of suffering or are suffering or have
suffered from a cardiovascular disease or an ischemic disease. Such
subjects may for example be subjects suffering from type 1 or type
2 diabetes and/or may be subjects suffering from obesity.
[0075] As used herein, the term "cardiovascular disease" refers to
diseases that involve the heart or blood vessels (arteries and
veins). The term refers to any disease that affects the
cardiovascular system. It also refers to diseases related to
atherosclerosis (arterial disease). Cardiovascular diseases
include, but are not limited to, aneurysm, angina, arrhythmia,
cardiomyopathy, cerebrovascular accident (stroke), cerebrovascular
disease, congenital heart disease, congestive heart failure,
myocarditis, valve disease, coronary artery disease, dilated
cardiomyopathy, diastolic dysfunction, endocarditis, high blood
pressure (hypertension), hypertrophic cardiomyopathy, mitral valve
prolapse, myocardial infarction (heart attack), venous
thromboembolism, ischemia and wound healing.
[0076] Additionally, any subject suffering from or being at risk of
suffering from vascular complications, cardiovascular diseases
associated with the metabolic syndrome or syndrome X or obesity,
atherosclerosis, primary atherosclerotic vascular degeneration such
as central and peripheral arteriopathy, or any subject in need of
vascular remodeling or in need of neovascularization would benefit
from being administered with the polypeptides of the invention. As
used herein, the expression syndrome X refers to a combination of
medical disorders that includes the risk of developing
cardiovascular diseases.
[0077] The term "oxidative stress" refers to an imbalance between
the production of reactive oxygen and a biological system's ability
to readily detoxify the reactive intermediates or easily repair the
resulting damages.
[0078] Any subject or patient that would benefit from an increase
in the CAC number and/or an improvement in CAC function would
benefit from administration of the polypeptides of the
invention.
[0079] CAC number refers to the amount or concentration of CAC that
home from the bone marrow into sites of vascular remodeling and/or
sites of neovascularization.
[0080] CAC function refers to the property of CAC to mobilize to a
site of endothelization (CAC mobilization), differentiate into
endothelial cells and participate in endothelization. Improvement
of CAC function refers to bringing into a more desirable condition
CAC function, such as for example, improving CAC mobilization
refers to bringing into a more desirable condition CAC
mobilization.
[0081] Any subject in need of vascular remodeling or vascular
restoration and/or in need of neovascularization would also benefit
from administration of the polypeptides of the invention.
[0082] The term "vascular remodeling" or "vascular restoration"
refers to any lasting changes in the diameter, thickness, or
structure of a mature blood vessel. The term "vascular remodeling"
also includes collateral vessel formation. For example, in
atherosclerosis, vascular remodeling acts as a compensatory
mechanism to preserve blood flow in the face of plaque growth,
which tends to cause stenosis or narrowing of the artery.
[0083] The term "neovascularization" refers to the formation of
functional microvascular networks with red blood cell
perfusion.
[0084] Improvement of vascular remodeling and/or neovascularization
refers to bringing into a more desirable condition vascular
remodeling and/or neovascularization.
[0085] The polypeptides of the invention are also useful to promote
engraftment of, for example, cells, tissues and/or organs or parts
thereof, in a transplant recipient such as an animal or a human. As
used herein, the term "engraftment" refers to incorporation of
grafted tissue into the body of a host. As used herein, the term
"engraftment" also refers to the process in which transplanted stem
cells or bone marrow cells migrate to the bone marrow and begin
producing blood cells.
[0086] The polypeptides described herein are also useful in
regenerative medicine or in tissue engineering to develop
biological substitutes that restore, maintain, or improve tissue
function of a whole organ or a part thereof, such as, for example,
the heart, blood vessels, bone marrow, or the like. The expression
"tissue engineering" also refers to the production of natural or
synthetic organs and tissues that can be implanted as fully
functional units or may develop to perform necessary functions
following implantation. The methods of regenerative medicine or
tissue engineering are known to those of skill in the art.
[0087] The polypeptides defined herein are also useful for
improving wound healing. In a specific but non-limiting example,
the polypeptides defined herein are also useful for improving wound
healing in diabetic patients such as improving healing of diabetic
ulcers.
[0088] The term "metabolic disorders" refers to, but is not limited
to, disorders of carbohydrate metabolism, disorders of amino acid
metabolism, disorders of organic acid metabolism (organic
acidurias), disorders of fatty acid oxidation and mitochondrial
metabolism, disorders of porphyrin metabolism, disorders of purine
or pyrimidine metabolism, disorders of steroid metabolism,
disorders of mitochondrial function, disorders of peroxisomal
function and lysosomal storage disorders.
[0089] The term "metabolic syndrome" refers to a combination of
medical disorders that increase one's risk for cardiovascular
disease and diabetes.
[0090] It is a further aspect of the present invention to provide
for any pharmaceutical composition incorporating at least one of
the polypeptides as defined herein.
[0091] For therapeutic and/or pharmaceutical uses, the polypeptides
as defined herein may be formulated for, but not limited to,
intravenous, subcutaneous, transdermal, topical, oral, buccal,
sublingual, nasal, inhalation, pulmonary, or parenteral
administration according to conventional methods. Intravenous
injection may be by bolus or infusion over a conventional period of
time. The polypeptides as defined herein may also be administered
directly to a target site within a subject e.g., by biolistic
delivery to an internal or external target site or by catheter to a
site in an artery.
[0092] Active ingredients, such as the polypeptides defined herein,
to be administered orally as a suspension can be prepared according
to techniques well known in the art of pharmaceutical formulation
and may contain, but not be limited to, microcrystalline cellulose
for imparting bulk, alginic acid or sodium alginate as a suspending
agent, methylcellulose as a viscosity enhancer, and
sweeteners/flavoring agents. As immediate release tablets, these
compositions may contain, but are not limited to microcrystalline
cellulose, dicalcium phosphate, starch, magnesium stearate and
lactose and/or other excipients, binders, extenders, disintegrants,
diluents and lubricants. The active ingredients may be administered
by way of a controlled-release delivery system.
[0093] Administered by nasal aerosol or inhalation formulations may
be prepared, for example, as solutions in saline, employing benzyl
alcohol or other suitable preservatives, absorption promoters to
enhance bioavailability, employing fluorocarbons, and/or employing
other solubilizing or dispersing agents.
[0094] The polypeptides of the invention may be administered in
intravenous (both bolus and infusion), intraperitoneal,
subcutaneous, topical with or without occlusion, or intramuscular
form. When administered by injection, the injectable solution or
suspension may be formulated using suitable non-toxic,
parenterally-acceptable diluents or solvents, well known in the
art.
[0095] The polypeptides of the invention may also be formulated for
topical administration. The term "topical" as used herein includes
any route of administration that enables the compounds to line the
skin or mucosal tissues. Topical administration of the polypeptides
defined herein is useful for example, to improve wound healing or
to improve wound treatment or for in situ treatment in a
subject.
[0096] The formulation suitable for topical application may be in
the form of, for example, cream, lotion, solution, gel, ointment,
paste, plaster, paint, bioadhesive, or the like, and/or may be
prepared so as to contain liposomes, micelles, microparticles
and/or microspheres. The formulation may be aqueous, i.e., contain
water, or may be nonaqueous and optionally used in combination with
an occlusive overlayer so that moisture evaporating from the body
surface is maintained within the formulation upon application to
the body surface and thereafter.
[0097] Ointments, as is well known in the art of pharmaceutical
formulation, are semisolid preparations that are typically based on
petrolatum or other petroleum derivatives. The specific ointment
base to be used, as will be appreciated by those skilled in the
art, is one that will provide for optimum delivery of the
polypeptides defined herein, and, preferably, will provide for
other desired characteristics as well, e.g., emolliency or the
like. Creams, as also well known in the art, are viscous liquids or
semisolid emulsions, either oil-in-water or water-in-oil. Cream
bases are water-washable, and contain an oil phase, an emulsifier,
and an aqueous phase. As will be appreciated by those working in
the field of pharmaceutical formulation, gels are semisolid,
suspension-type systems. Single-phase gels contain organic
macromolecules distributed substantially uniformly throughout the
carrier liquid, which is typically aqueous, but also, preferably,
contain an alcohol and, optionally, an oil. Lotions, which are
preferred for delivery of cosmetic agents, are preparations to be
applied to the skin surface without friction, and are typically
liquid or semiliquid preparations in which solid particles,
including the active agent, are present in a water or alcohol base.
Lotions are usually suspensions of solids. Pastes are semisolid
dosage forms in which the active agent is suspended in a suitable
base. Depending on the nature of the base, pastes are divided
between fatty pastes or those made from a single-phase aqueous
gels. Plasters are comprised of a pasty mixture that is spread on
the body, either directly or after being saturated into a base
material such as cloth. Formulations of the invention, may be
dissolved or dispersed within the plaster to make a medicated
plaster. Bioadhesives are preparations that adhere to surfaces of
body tissues. Polymeric bioadhesive formulations are well known in
the art.
[0098] Formulations may also be prepared with liposomes, micelles,
microparticles and/or microspheres. Liposomes are microscopic
vesicles having a lipid wall comprising a lipid bilayer, and can be
used as drug delivery systems. Micelles are known in the art to be
comprised of surfactant molecules arranged so that their polar
headgroups form an outer spherical shell, while the hydrophobic,
hydrocarbon chains are oriented towards the center of the sphere,
forming a core. Microparticles are particulate carrier systems in
the micron size range, normally prepared with polymers, which can
be used as delivery systems for drugs or vaccines that are usually
trapped within the particles. Microspheres, similarly, may be
incorporated into the present formulations and drug delivery
systems. Like liposomes and micelles, microspheres essentially
encapsulate a drug or drug-containing formulation. Microspheres are
generally, although not necessarily, formed from synthetic or
naturally occurring biocompatible polymers, but may also be
comprised of charged lipids such as phospholipids.
[0099] Preparation of formulations suitable for topical
administration are well known in the art and described in the
pertinent texts and literature.
[0100] In general, pharmaceutical compositions will comprise at
least one of the polypeptides of the invention together with a
pharmaceutically acceptable carrier which will be well known to
those skilled in the art. The compositions may further comprise for
example, one or more suitable excipients, diluents, fillers,
solubilizers, preservatives, salts, buffering agents and other
materials well known in the art depending upon the dosage form
utilized. Methods of composition are well known in the art.
[0101] In the present context, the term "pharmaceutically
acceptable carrier" is intended to denote any material, which is
inert in the sense that it substantially does not have any
therapeutic and/or prophylactic effect per se and that are
non-toxic. A pharmaceutically acceptable carrier may be added to
the polypeptides of the invention with the purpose of making it
possible to obtain a pharmaceutical composition, which has
acceptable technical properties.
[0102] Examples of such carriers include ion exchangers, alumina,
aluminum stearate, lecithin, serum proteins, such as human serum
albumin, buffer substances such as phosphates, glycine, sorbic
acid, potassium sorbate, partial glyceride mixtures of saturated
vegetable fatty acids, water, salts, or electrolytes such as
protamine sulfate, disodium hydrogen phosphate, potassium hydrogen
phosphate, sodium chloride, zinc salts, colloidal silica, magnesium
trisilicate, polyvinyl pyrrolidone, cellulose-based substances, and
PEG.
[0103] Carriers for topical or gel-based forms of polypeptides
include polysaccharides such as sodium carboxymethylcellulose or
methylcellulose, polyvinylpyrrolidone, polyacrylates,
polyoxyethylene-polyoxypropylene-block polymers, PEG, and wood wax
alcohols.
[0104] The polypeptides used for in vivo administration must be
sterile. This may be accomplished by filtration through sterile
filtration membranes, prior to or following lyophilization and
reconstitution. The polypeptidesordinarily will be stored in
lyophilized form or in solution. Therapeutic polypeptide
compositions generally are placed into a container having a sterile
access port, for example, an intravenous solution bag or vial
having a stopper pierceable by a hypodermic injection needle.
[0105] For use in the methods defined herein, the invention also
provides an article of manufacture or a commercial package or kit,
comprising: a container, a label on the container, and a
composition comprising the polypeptides of the invention as an
active agent within the container when used at the indicated level,
wherein the composition is effective for, inter alia, the treatment
of a cardiovascular disease and/or for improving vascular
remodeling or neovascularization and/or increasing CAC number and
improving CAC function and/or to improve wound healing, and/or to
be used in or facilitate engraftment and/or tissue engineering. The
label on the container indicates for what the composition can be
used.
[0106] A "therapeutically effective amount" refers to an amount
effective, at dosages and for periods of time necessary, to achieve
the desired therapeutic result. A therapeutically effective amount
of the peptides noted herein may vary according to factors such as
the disease state, age, sex, and weight of the individual, and the
ability of the compound to elicit a desired response in the
individual. Dosage regimens may be adjusted to provide the optimum
therapeutic response. A therapeutically effective amount is also
one in which any toxic or detrimental effects of the compound are
outweighed by the therapeutically beneficial effects. A
"prophylactically effective amount" refers to an amount effective,
at dosages and for periods of time necessary, to achieve the
desired prophylactic result, such as preventing or inhibiting the
onset of a condition related to insulin levels and/or activity. A
prophylactically effective amount can be determined as described
above for the therapeutically effective amount. For any particular
subject, specific dosage regimens may be adjusted over time
according to the individual need and the professional judgement of
the person administering or supervising the administration of the
compositions.
[0107] For example, a therapeutically effective amount or effective
dose of the peptides of the invention (also referred to herein as
"active compound") is an amount sufficient to improve or ameliorate
impaired vascular remodeling in a subject or patient with
cardiovascular risk, or to treat a subject or a patient with a
cardiovascular disease or an ischemic disease, to improve
engraftment, to improve engraftment associated with or following
transplantation of an organ or a part thereof, to be used in or to
improve or facilitate in vitro or ex vivo tissue engineering, such
as, but not limited to blood vessels engineering, to improve wound
healing, to improve wound healing in diabetic patients, such as
diabetic patients suffering from diabetic ulcers. The methods
and/or assays for measuring such parameters are known to those of
ordinary skill in the art.
[0108] The therapeutically effective amount of the invention will
generally vary from about 0.001 .mu.g/kg to about 10 mg/kg, more
particularly from about 0.01 .mu.g/kg to about 10 mg/kg, and even
more particularly from about 1 .mu.g/kg to about 1 mg/kg.
Therapeutically effective amounts or effective doses that are
outside this range but that have the desired therapeutic effect are
also encompassed by the present invention.
[0109] In a one aspect, the subject noted above is a mammal, in a
further aspect, a human.
Experiments and Data Analysis
[0110] In the experiments and data analysis provided below, a
cardiovascular risk or disease situation was reproduced by
performing some of the experiments in a diabetes setting. A person
skilled in the art will appreciate that the data obtained may be
extrapolated to other physiological conditions or settings which
are or may be determined to be associated with impairment of CAC
biological function.
UAG Effect on CAC Cell Mobilization and Metabolism
[0111] I. UAG Protects CAC from Oxidative Stress
[0112] Oxidative stress plays a major role in tissue damage (Ref.
21) and endothelial injury associated with diabetes mainly depends
on the production of reactive oxygen species (ROS). The observation
that UAG or AG protects endothelial cells from apoptosis (Ref. 8)
led to evaluate the effect of both ghrelin isoforms on CAC
biology.
[0113] First, cell-cycle progression in response to UAG and AG was
evaluated. As shown in FIG. 1A, UAG, but not AG, was able to induce
a significant increase in the percentage of cells in S phase, and
this effect was still evident after 7 days of culture. To
investigate whether this effect relies on inhibition of baseline
ROS production, DCF-DA assay was performed. The results, reported
in FIG. 1B, reveal that UAG treatment drastically reduces the
baseline level of ROS production when compared to untreated cells.
A protective effect failed to be detected when AG was used (FIG.
1B). FIG. 1E reveals that a fragment of UAG, namely UAG (6-13) also
reduces the baseline level of ROS production when compared to
untreated cells. H.sub.2O.sub.2 was used as positive control.
AGE-mediated damage signals mainly rely on ROS production (Ref.
29). As depicted in FIGS. 1C and 1F, the level of ROS production in
AGE-cultured cells was reduced when cells were challenged with UAG
or with UAG (6-13) fragment. Consistent with the above results, no
effects could be detected with AG. To further confirm these data,
CAC were isolated from type 2 diabetic patients and subjected to
UAG or AG treatment. Data reported in FIG. 1D reveal that UAG, but
not AG, reduced intracellular ROS production in diabetic-recovered
cells.
II. UAG Prevents CAC Senescence
[0114] Apart from DNA damage, stress-caused signals also induce
senescent-like growth arrest (Ref. 30). p53, p21, and pRb are the
major regulators of senescence and ROS production is generally
considered as an upstream signal. It was previously shown that an
accelerated onset of senescence can be detected in EPC from
diabetic patients (Ref. 22). The above data led to evaluate whether
ROS production translates into an accelerated onset of senescence
and whether UAG could rescue this effect.
[0115] To this end, the effect of AGE treatment, alone or in
combination with UAG, was first evaluated on SA-.beta.-gal
activity. Consistent with the results on ROS production, UAG was
able to reduce the number of senescent cells (FIG. 2A). In
addition, a significant reduction in the number of SA-.beta.-gal
positive cells could also be detected when UAG was added to
AGE-cultured CAC (FIG. 2A). The role of p53, p21 and pRb in
mediating this event is sustained by the observation that UAG
prevented p53 accumulation, p21 expression and phosphorylation of
Rb induced by AGE (FIG. 2B). In addition, AGE-induced p53
accumulation and senescent like-growth arrest were prevented by
silencing p53 (FIG. 2C).
[0116] To further confirm these data, type 2 diabetic patients were
subjected to UAG treatment. After 12 hours of treatment, CAC were
recovered from UAG treated and untreated patients and cultured. As
shown in FIGS. 2D and 2E, when administered in vivo, UAG reduced
the number of senescent cells and prevented p53 accumulation,
phosphorylation of Rb and p21 expression. These data further
confirm that a p53-mediated signalling pathway contributes to the
impaired CAC function in a diabetic setting and that UAG can
prevent these events.
III. UAG Affects CAC Mobilization
[0117] CAC physiologically populate in BM and mobilize into
circulation in response to microenvironment changes. Impairment in
CAC mobilization has been reported in patients with cardiovascular
risk factors (Refs. 19, 31).
[0118] This observation led to investigate the effect of UAG
treatment on BM CAC mobilization. To this end, normal subject and
diabetic patients were treated with UAG or saline for 6 hours.
After treatment, CAC were recovered from 4 control subjects and 4
diabetic patients, analyzed by FACS analysis and counted. As shown
in FIG. 3A, FACS analysis on CAC recovered from UAG-treated
patients demonstrated that indeed the recovered cells were CAC as
shown by a high expression of the CD45 marker, low frequency of
CD14 monocyte marker and no expression of the endothelial
differentiation markers CD146 and CD105. Black lines refer to
preimmune IgG used as negative control and grey lines refer to
surface marker expression. Similar results were obtained when CAC
from untreated diabetic patients or untreated or treated healthy
subjects were analyzed (data not shown). Interestingly, UAG
treatment, but not AG treatment, led to a strong increase in the
number of recovered cells in diabetic patients compared to normal
subjects (FIG. 3B). No statistical differences were detected in
diabetic patients and controls treated with AG or saline.
[0119] To confirm their vascular features, the cells recovered from
patients and controls were cultured with IL-3; which is able to
induce expansion and arterial morphogenesis of CD45.sup.+ cells
derived from both peripheral blood and BM (Ref. 28). As shown in
FIG. 3C, cells recovered from UAG-treated diabetic patients, but
not from AG-treated diabetic patients, underwent cell expansion.
Moreover, as reported in FIG. 3D, when arterial morphogenesis was
evaluated by quantitative (Q)-RT-PCR for arterial markers (Ephrin
B2, Notch1 and Notch4) or for venous marker (EphB4), it was found
that only cells obtained from UAG-treated patients were also able
to undergo arterial specification. These data further indicate that
diabetes-associated CAC impairment can be rescued by UAG
challenge.
[0120] To further confirm data obtained by treating patients and
healthy controls with UAG, two different mouse models of diabetes
were used. NOD/SCID mice and ob/ob mice were treated for different
time intervals with saline or UAG. The person skilled in the art
will be familiar with the NOD/SCID mice and ob/ob mice models.
[0121] After treatment, cells were recovered, assayed by FACS
analysis, counted and cultured. As shown in FIG. 4A, FACS analysis
demonstrates that, as with the human counterpart, cells recovered
from UAG-treated ob/ob mice expressed the CD45 marker and CD31,
KDR, but not CD33. Black lines refer to preimmune IgG used as
negative control and grey lines refer to surface marker expression.
Similar results were obtained when CAC from untreated diabetic mice
as well as untreated or treated wild-type mice were analyzed (data
not shown). Moreover, unlike in not diabetic NOD/SCID mice, in
diabetic NOD/SCID mice, UAG challenge was able to increase the
percentage of recovered cells (FIG. 4B). The increased number of
circulating CAC could also be detected in ob/ob mice challenged
with UAG. Of interest, the number of cells recovered from
UAG-treated ob/ob mice paralleled that of untreated wild type mice,
indicating that UAG fully restores the number of CAC to normal
physiological levels (FIG. 4B). Consistent with the human
counterpart, CAC recovered from UAG-challenged mice could be
expanded (FIG. 4C) and acquire arterial commitment when cultured in
the presence of IL-3 (FIG. 4D).
UAG Effect Vascular Remodeling and Neovascularization
IV. UAG Treatment Rescues the Functional Impairment of Diabetic
CAC
[0122] Emerging data indicate that progenitor cells are able to
incorporate into existing vascular structures to form new vessels
and improve perfusion (Ref. 33). To evaluate whether CAC recovered
from UAG-treated diabetic patients rescue their vasculogenic
capability, de novo vessel formation was assayed in vivo. To this
end, Matrigel plugs containing IL-3 and CSFE-labelled CAC,
recovered from untreated or UAG-treated patients, were injected
into SCID mice, 15 days after injection Matrigel plugs were
recovered and analyzed by immunohistochemistry. The results,
reported in FIG. 4E, demonstrate that many of these labelled cells
formed functional vessels as documented by erythrocytes in their
lumen (FIG. 4E, panel b (right)). On the contrary no functional
vessels could be detected when CAC recovered from untreated
patients were used (FIG. 4E, panel a (left)). To exclude the
possibility that the neo-vessels derived from vasculogenic cells of
host origin, immunofluorescence assay was performed using the
anti-human HLA Class I and the anti-mouse MHC II antibodies. It was
found that the majority of vessels are lined by human HLA Class I
positive cells (FIG. 4F). Thus, these data provide further evidence
that UAG treatment improves CAC availability and vascular
remodeling capability.
V. Presence of UAG Binding Sites on Human CAC
[0123] The presence of specific binding sites for UAG on CAC
membranes was investigated by evaluating the ability of 100 nM
unlabelled UAG (1-28) to compete with [.sup.125I-Tyr.sup.4]-UAG
(0.25 nM) for such binding sites. The specificity of the binding
was also tested in the presence of 100 nM AG (1-28) (acylated
ghrelin), UAG (28-1), a biologically inactive ghrelin analog, and a
synthetic UAG (6-13)-NH.sub.2 fragment. The results of this
competition binding study (FIG. 5A) revealed that the binding of
[.sup.125I-Tyr.sup.4]-UAG to CAC membranes was inhibited by both
UAG (1-28) and UAG (6-13), but not by AG (1-28) or UAG (28-1). The
specific binding of [.sup.125I-Tyr.sup.4]-UAG (calculated as
difference between binding in the absence, control, and in the
presence of UAG) represented about 75% of the control value
(P<0.001) and was detected either on fresh (0.25 and 0.26 fmol)
or frozen-thawed (0.20 and 0.33 fmol) CAC membranes from two
different cell preparations.
[0124] A saturation binding experiment was performed on membranes
from a CAC preparation that yielded sufficient amounts of membranes
for this experiment, revealed that the specific binding of the
radioligand to CAC membranes was saturable (FIG. 5B), reaching a
maximum at 2 nM, a concentration consistent with the physiological
circulating UAG levels. Scatchard analysis of these data (data not
shown) suggests the existence on CAC cells of a single class (Hill
coefficient close to 1) of unacylated ghrelin binding sites with a
K.sub.d of 0.48 nM and a B.sub.max of 10.7 fmol/mg membrane
protein. These results indicate that UAG is able to bind to CAC
cells with high affinity.
Materials and Technical Protocols
[0125] Patients and Controls--Blood was recovered from six type 2
diabetic patients (sex, M/F 5/1; HbA1c, 8.+-.1.2%; age-years,
62.8.+-.12.46; BMI, 27.1.+-.3.22 creatinine, 1.04.+-.0.20 mg/dl;
waist circumference (cm), 98.2.+-.7.52, total cholesterol,
192.+-.50 mmol/L, HDL cholesterol, 46.+-.13.98 mmol/L, LDL
cholesterol, 113.+-.39.77 mmol/L, Triglycerides, 157.5.+-.54.23,
fasting glucose 126.+-.19.04 mg/dl no retinopathy, hypertension in
3 patients, blood pressure 141/87 mm Hg; Chol/apoB, 1.3.+-.0.1).
All were treated only with diet (no other medicaments were used by
diabetic patients). Eight blood donors were used as controls (sex,
M/F 4/4; age-years, 26.6.+-.4.65; BMI 21.14.+-.8.08, creatinine,
0.96.+-.0.063 mg/dl, total cholesterol, 162.13.+-.10.79 mmol/L, HDL
cholesterol, 49.+-.10.4 mmol/L, LDL cholesterol, 86.25.+-.17.72
mmol/L, Triglycerides, 132.13.+-.27.10, no retinopathy, no
hypertension: blood pressure 125/70 mm Hg, Chol/apoB,
1.6.+-.0.1).
[0126] All the subjects underwent the following testing session:
[0127] UAG (3.0 .mu.g/kg/h iv. as infusion for 12 h from 0 to 12
hours); [0128] isotonic saline (infusion from 0 to 12 hours).
[0129] All tests were performed starting at 08.30-09.00 a.m. after
overnight fasting, 30 minutes after an indwelling catheter had been
placed into a forearm vein by slow infusion of isotonic saline.
Blood samples were taken at Oh, 6 h and 12 h.
[0130] Reagents--M199 medium (endotoxin tested), bovine serum
albumin, fetal bovine serum (FBS), glycated human albumin (AGE)
were from Sigma-Aldrich (St Louis, Mo.). Bovine calf serum
(endotoxin-tested) was obtained from HyClone (Logan, Utah). Trypsin
was purchased from Difco. Nitrocellulose filters, horseradish
peroxidase-conjugated anti-rabbit IgG and anti-mouse IgG, molecular
weight markers, and chemiluminescence reagents (ECL) were from
Amersham Biosciences. The acidic .beta.-galactosidase staining kit
was from Invitrogen. Peroxide hydrogen was obtained from Carlo Erba
reagents. The presence of endotoxin contamination was tested by the
Limulus amebocyte assay (concentration was <0.1 ng/ml). Human
IL-3 was a gift from Sandoz Pharma Ltd (Basel, Switzerland). Human
UAG was purchased from Phoenix Europe GmbH (Karlsruhe,
Germany).
[0131] Antibodies--Monoclonal anti-p53 clone DO-1, anti-CD31,
anti-Flk1/KDR, anti-CD33 FITC, anti-.beta.-actin, anti-p21, were
obtained from Santa Cruz Biotechnology, Inc. (Heidelberg, Germany).
Phospho-Rb was from Cell Signaling Technology (Beverly, Mass.).
Anti-mouse CD45 PE, anti-CD14 PE, anti-human CD45 FITC antisera
were from Miltenyi Biotec Inc. (Auburn, Calif., USA).
Anti-CD146-FITC antibody was from BioCytex (Marseille, France).
Anti-CD105 FITC antibody was purchased from Tecnogenetics s.r.l.
(Milano, Italy). Secondary FITC or PE antibodies were from Miltenyi
Biotech Inc. and from Sigma. Anti-human HLA Class I antibody was
from Sigma-Aldrich while anti-mouse MHC II antibody from Chemicon
(Temecula, Calif., USA).
[0132] Isolation and Culture of CAC from Peripheral Blood
Mononuclear Cells--Peripheral-blood mononuclear cells (PB-MNC)
isolated by Fycoll Histopaque 1077 (Sigma) were resuspended in 20%
FBS 199 Medium and plated on fibronectin-coated dishes (Biocoat,
Becton Dickinson Labware) as described by Hill et al. (Ref. 19).
Human UAG studies were performed on CAC recovered from normal
donors and diabetic patients. The purity of sorted cells was
assessed by FACS analysis (Ref. 20). For experiments, the isolated
CAC were cultured under 5% CO.sub.2 at 37.degree. C. for 4 days on
20 .mu.g/ml fibronectin-coated dishes in EGM-2 medium containing
10% FBS, hydrocortisone, human Fibroblast Growth Factor, Vascular
Endothelial Growth Factor, Insulin Growth Factor 1, ascorbic acid,
human Epidermal Growth Factor, gentamicin and amphotericin-B
(Cambrex, Walkersville, Md., USA) alone or in combination with 1
.mu.M UAG and 1.2 mg/ml AGE. In selected experiments, isolated CAC
were cultured in EBM-2 medium (Cambrex, Walkersville, Md., USA)
supplemented with 10 ng/ml of IL-3. FACS was used to analyze their
phenotype (anti-CD45, anti-CD31, anti-CD105, anti-CD14 antibodies
were used)(Ref. 22).
[0133] Mobilization assay--CAC recovered from healthy subjects and
diabetic patients, treated with UAG or saline for 6 h and 12 h,
were evaluated. Total number of MNC was counted by 3 independent
investigators. The percentage of CAC was calculated by comparing
CAC obtained from diabetic patients and healthy donors, treated for
6 h and 12 h with UAG, AG or saline, to CAC recovered at time
0.
[0134] Silencing of Endogenous p53 by Small Interfering RNAs
(siRNA)--To obtain inactivation of p53, CAC recovered from normal
subjects cultured with or without AGE were transiently transfected
by Lipofectamine PLUS.TM. reagent (Invitrogen) according to the
vendor's instructions with the vector pSUPER retro containing p53
siRNA or a scramble p53 siRNA (control siRNA) sequences (1.5 .mu.g)
as described by Brummelkamp et al. (Ref. 23). The pSUPER retro
containing p53 siRNA and the scramble p53 siRNA were gently
provided by Dr. S. Soddu. 60 h later whole cell extracts were
prepared, separated on 10% SDS-PAGE, and immunoblotted with
anti-p53 antibody.
[0135] Detection of ROS--DCF-DA (0.5 .mu.M final concentration) was
added to CAC in the indicated culture conditions. At the indicated
times, the cells were subjected to FACS analysis and processed as
previously described (Ref. 22). H.sub.2O.sub.2 was used as positive
control.
[0136] CAC Senescence--Senescence was evaluated by acidic
.beta.-gal activity on CAC recovered from normal subjects cultured
in EGM2 medium for 4 days with UAG or AGE+UAG and saline- or
UAG-treated diabetic patients (Ref. 22). Briefly, CAC were washed
in phosphate-buffered saline, fixed for 3 min at room temperature
in 2% paraformaldehyde, washed, and incubated for 24 h at
37.degree. C. with fresh SA-.beta.-gal stain solution: 1 mg/ml
5-bromo-4-chloro-3-indolyl .beta.-D-galactopyranoside (X-gal), 5
mM/liter potassium ferrocyanide, 5 mM/liter ferricyanide, 150
mM/liter NaCl, 2 mM/liter MgCl.sub.2, 0.01% sodium deoxycholate,
and 0.02% Nonidet P-40. SA-.beta.-gal-positive cells were counted
manually by 3 independent investigators.
[0137] Western Blot Analysis--CAC from healthy donors cultured in
the presence of UAG, in combination or not with AGE, and CAC
recovered from diabetic patients treated with saline or UAG were
lysed. Protein concentration was detected as previously described
(Ref. 24). 50 .mu.g of proteins were separated on
SDS-polyacrylamide gels and transferred to nitrocellulose
membranes. Reaction with anti-p53, anti p21 and anti-phospho-Rb
antibodies and detection with an enhanced chemiluminescence
detection system (Amersham Biosciences) were performed as described
previously (Ref. 20).
[0138] RNA isolation and quantitative real-time PCR--CAC from
diabetic patients, healthy subjects and mice treated with UAG or
saline were cultured in EGM-2 medium. Human arterial and venous
cells were used as a positive controls. mRNA quantification was
performed by Q-RT-PCR, as previously described (Ref. 24). The
relative expression of Ephrin B2, Notch1, Notch4 and EphB4 were
calculated by using comparative threshold cycle methods. The human
and murine primer sequences used were described (Refs. 25, 26).
[0139] Flow Cytometry--To analyze CAC cell-cycle progression, cells
recovered from diabetic, healthy subjects, NOD/SCID, ob/ob and wt
mice, were cultured in EBM-2 supplemented with IL-3 (10 ng/ml),
FACS analysis was performed as previously described (Ref. 20). Cell
surface molecules were evaluated by flow cytometry as previously
described (Ref. 24). Frequency of marker-positive cells is
expressed as mean.+-.standard deviation (SD).
In Vivo Experiments
[0140] Diabetic and control mice--Mice were divided in four groups.
The plasma glucose and insulin determination for each group are
reported. Sixteen 6 weeks old ob/ob mice (blood glucose, 600.+-.45
mg/dL, insulin, 5.5.+-.0.9 ng/ml); sixteen C56BL6/J wild type mice
(blood glucose, 150.+-.18.2 mg/dL, insulin, 1.+-.0.05 ng/ml); ten 7
weeks old NOD/SCID mice (blood glucose, 164.+-.12.9 mg/dL, insulin
1.2.+-..0.12 ng/ml); ten 17 weeks old NOD/SCID mice (blood glucose,
536.+-.36.3 mg/dL, insulin 4.85.+-.0.74 ng/ml). Animal procedures
conformed to the Guide for Care and Use of Laboratory Resources
(National Institutes of Health publication no. 93-23, revised
1985).
[0141] Blood glucose and serum insulin determinations--Blood
glucose was measured with a One Touch II glucose meter (Lifescane,
Mountain View, Calif.). Serum insulin was measured with a mouse
insulin radioimmumoassay kit (Linco Research immunoassay, St.
Charles, Mo.), following the manufacturer's instructions.
[0142] Isolation and Culture of CAC from C57BL/6J, C57BL/6J ob/ob
mice and NOD/SCID mice--6 weeks old C57BL/6J (wt) and ob/ob mice, 7
and 17 weeks old NOD/SCID mice were purchased from Charles River
Lab (Lecco, Italy). Animals were anesthetized by intraperitoneal
injection with Avertin (100 mg/50 ml ip). Blood samples were drawn
from left ventricular, as described by Hoff (Ref. 27). Peripheral
blood MNC were isolated by Ficoll density-gradient centrifugation.
Recovered cells were washed twice. Isolated cells were resuspended
and were cultured on 20 .mu.g/ml fibronectin-coated dishes in EGM-2
BulletKit Medium. In selected experiments, the isolated CAC were
cultured in EBM-2 medium supplemented with 10 ng/ml of IL-3.
[0143] Mobilization assay--Mice were treated for 12 hours with UAG
or saline. CAC recovered and purified as above described, were put
in culture and counted by three independent investigators. The
technical ratio of CAC was calculated by comparing the numbers of
CAC/.mu.L of blood drawn from left ventricular.
[0144] Matrigel-plug assay--For murine angiogenesis assay,
untreated or UAG-treated CAC, obtained from type 2 diabetic
patients, were counted and resuspended in DMEM (4.times.10.sup.6 in
250 .mu.L DMEM). Cells were chilled in ice, labelled with
fluorescent dye carboxyfluorescein diacetate succinimidyl ester
(CSFE, Molecular Probes), added to 250 .mu.L Matrigel containing of
IL-3 (100 ng/ml) at 4.degree. C., and injected sc. in the abdominal
paramedian region of 7 week old NOD/SCID mice (5 mice per group).
After 15 days, mice were killed and Matrigel plugs were recovered,
fixed in 10% buffered formalin and embedded in paraffin for
immunohistochemistry.
[0145] Immunohistochemistry and immunofluorescence--For
immunohistochemistry, sections from paraffin-embedded blocks of
Matrigel plugs were collected onto poly-lysine-coated slides.
Endogenous peroxidase activity was blocked with 6% H.sub.2O.sub.2
for 8 minutes at room temperature. To detect cells labelled with
fluorescent dye CSFE, anti-Fluorescein/Oregon Green polyclonal Abs
(Molecular Probes) were applied to slides overnight at 4.degree. C.
Horseradish peroxidase-labeled antirabbit Envision polymer
(DakoCytomation, Carpinteria, Calif.) was incubated for 30 minutes.
The reaction product was developed using 3,3-diaminobenzidine.
Omission of the primary Ab or substitution with an unrelated rabbit
serum IgG used as negative control. The percentage of positive
cells was counted in 4 non-sequential sections for each experiment
at .times.40 magnification. For immunofluorescence, the samples
were processed using anti-human HLA I and anti-mouse MHC II
antibodies as previously described (Ref. 28). The number of MHC II
or HLA I positive vessels was determined by counting 10 randomly
selected fields in three different samples.
[0146] Statistical analysis--In vitro and in vivo results are
representative of at least three independent experiments. The in
vitro experiments were performed in triplicate. Densitometric
analysis using a Bio-Rad GS 250 molecular imager was used to
calculate the differences in the fold induction of protein
activation or expression (* and .sctn. p<0.05, statistically
significant between experimental and control values). Significance
of differences between experimental and control values was
calculated using analysis of variance with Newman-Keuls
multicomparison test. Similar statistical analysis was performed in
the in vivo experiments.
[0147] It is understood that the data reported in the present
specification are only given to illustrate the invention and may
not be regarded as constituting a limitation thereof.
[0148] While the invention has been described in connection with
specific embodiments thereof, it will be understood that it is
capable of further modifications and this application is intended
to cover any variations, uses, or adaptations of the invention
following, in general, the principles of the invention and
including such departures from the present disclosure as come
within known or customary practice within the art to which the
invention pertains and as may be applied to the essential features
hereinbefore set forth, and as follows in the scope of the appended
claims.
[0149] All documents mentioned in the specification are herein
incorporated by reference.
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Sequence CWU 1
1
8128PRTHomo sapiens 1Gly Ser Ser Phe Leu Ser Pro Glu His Gln Arg
Val Gln Gln Arg Lys1 5 10 15Glu Ser Lys Lys Pro Pro Ala Lys Leu Gln
Pro Arg 20 25214PRTHomo sapiens 2Gly Ser Ser Phe Leu Ser Pro Glu
His Gln Arg Val Gln Gln1 5 10318PRTHomo sapiens 3Gly Ser Ser Phe
Leu Ser Pro Glu His Gln Arg Val Gln Gln Arg Lys1 5 10 15Glu
Ser45PRTHomo sapiens 4Gly Ser Ser Phe Leu1 5512PRTHomo sapiens 5Glu
Ser Lys Lys Pro Pro Ala Lys Leu Gln Pro Arg1 5 1068PRTHomo sapiens
6Ser Pro Glu His Gln Arg Val Gln1 576PRTHomo sapiens 7Glu His Gln
Arg Val Gln1 585PRTHomo sapiens 8Glu His Gln Arg Val1 5
* * * * *