U.S. patent application number 16/211757 was filed with the patent office on 2019-03-28 for amidated dopamine neuron stimulating peptides for cns dopaminergic upregulation.
The applicant listed for this patent is University of Kentucky Research Foundation. Invention is credited to Luke H. Bradley, Don M. Gash, Greg A. Gerhardt.
Application Number | 20190091284 16/211757 |
Document ID | / |
Family ID | 44277987 |
Filed Date | 2019-03-28 |
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United States Patent
Application |
20190091284 |
Kind Code |
A1 |
Bradley; Luke H. ; et
al. |
March 28, 2019 |
Amidated Dopamine Neuron Stimulating Peptides for CNS Dopaminergic
Upregulation
Abstract
The present invention relates to novel proteins, referred to
herein as amidated glial cell line-derived neurotrophic factor
(GDNF) peptides (or "Amidated Dopamine Neuron Stimulating peptides
(ADNS peptides)"), that are useful for treating brain diseases and
injuries that result in dopaminergic deficiencies.
Inventors: |
Bradley; Luke H.;
(Lexington, KY) ; Gash; Don M.; (Lexington,
KY) ; Gerhardt; Greg A.; (Nicholasville, KY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
University of Kentucky Research Foundation |
Lexington |
MA |
US |
|
|
Family ID: |
44277987 |
Appl. No.: |
16/211757 |
Filed: |
December 6, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15445206 |
Feb 28, 2017 |
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16211757 |
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14153844 |
Jan 13, 2014 |
9586992 |
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15445206 |
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12646511 |
Dec 23, 2009 |
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14153844 |
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12508916 |
Jul 24, 2009 |
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12646511 |
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12447213 |
Mar 25, 2010 |
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PCT/US2007/022696 |
Oct 26, 2007 |
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12508916 |
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60854693 |
Oct 27, 2006 |
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61140365 |
Dec 23, 2008 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07K 7/08 20130101; A61K
38/10 20130101; C07K 7/06 20130101; A61P 25/16 20180101; A61K 38/08
20130101; A61P 25/00 20180101 |
International
Class: |
A61K 38/10 20060101
A61K038/10; C07K 7/06 20060101 C07K007/06; C07K 7/08 20060101
C07K007/08; A61K 38/08 20060101 A61K038/08 |
Goverment Interests
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with U.S. government support under
grant numbers PO1 AG13494, P50 NS39787-01 and T32 AG000242 awarded
by the National Institutes of Health. The U.S. government has
certain rights in the invention.
Claims
1. A method for reducing apoptosis of a neuron by delivering to the
neuron a composition comprising at least one of the following
peptides: (a) a purified Amidated Dopamine Neuron Stimulating
peptide (ADNS peptide) comprising the amino acid sequence
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2); (b) a purified ADNS peptide
comprising the amino acid sequence FPLPA-amide (SEQ ID NO: 3); and
(c) a purified ADNS peptide comprising the amino acid sequence
PPEAPAEDRSL-amide (SEQ ID NO: 4) wherein the composition comprises
an amount of the ADNS peptide sufficient to reduce apoptosis, as
evidenced by an increase in GAPDH localization in the cytosol or
membrane and/or as evidenced by a reduction in capase-3 activity
and/or restoration of mitochondrial membrane potential and/or
reduction of cytochrome c release from mitochondria in the neuron
after the peptide is delivered to the neuron.
2. The method of claim 1 wherein the composition comprises a
purified ADNS peptide comprising the amino acid sequence
PPEAPAEDRSL-amide (SEQ ID NO: 4).
3-6. (canceled)
7. The method of claim 1, wherein the ADNS peptide is a purified
ADNS peptide comprising the amino acid sequence
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2).
8. The method of claim 1, wherein the ADNS peptide is a purified
ADNS peptide comprising the amino acid sequence FPLPA-amide (SEQ ID
NO: 3).
9. The method of claim 7 wherein the amount of ADNS peptide
sufficient to reduce apoptosis is determined by detecting an
increase in GAPDH localization in the cytosol or membrane after the
cells are contacted with the peptide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 15/445,206, filed on Feb. 28, 2017, which is a continuation of
U.S. application Ser. No. 14/153,844, filed on Jan. 13, 2014, which
is a divisional of U.S. application Ser. No. 12/646,511, filed Dec.
23, 2009, which is a continuation-in-part of U.S. application Ser.
No. 12/508,916, filed Jul. 24, 2009, which is a
continuation-in-part of U.S. application Ser. No. 12/447,213, filed
Mar. 25, 2010, which is a 371 application of PCT/US2007/022696,
filed Oct. 26, 2007, which claims priority of U.S. Application No.
60/854,693, filed Oct. 27, 2006, the disclosures of which are
incorporated herein in their entireties. This application claims
priority under 35 U.S.C. 119(e) to U.S. Provisional Application No.
61/140,365, filed Dec. 23, 2008, incorporated herein in its
entirety by reference.
FIELD OF THE INVENTION
[0003] The present invention relates to novel proteins, referred to
herein as amidated glial cell line-derived neurotrophic factor
(GDNF) peptides (or "Amidated Dopamine Neuron Stimulating peptides
(ADNS peptides)"), that are useful for treating brain diseases and
injuries that result in dopaminergic deficiencies.
BACKGROUND OF THE INVENTION
[0004] Neurotrophic factors are endogenous proteins that modulate
cell signaling pathways regulating stem cell proliferation,
neuronal differentiation, differentiation, growth and regeneration
(Barde Y., "Trophic factors and neuronal survival", Neuron
2:1525-1534 (1989); Gotz, R., et al., "The conservation of
neurotrophic factors during vertebrate evolution", Comp Biochem
Physiol Pharmacol Toxicol Endocrinol 108: 1-10 (1994); and Goldman,
S. A., "Adult neurogenesis: from canaries to the clinic", J
Neurobiol 36: 267-86 (1998)). They are generally small, soluble
proteins with molecular weights between 13 and 24 KDa and often
function as homodimers. Because of this physiological role,
neurotrophic factors are useful in treating the degeneration of
nerve cells and the loss of differentiated function that occurs in
a variety of neurodegenerative diseases.
[0005] Many neurotrophic factors are both neuroprotective
(protecting neurons from injury) and neurorestorative (promoting
structural and functional regeneration). The best defined
protective functions are seen during neural development. During
development, excessive numbers of neurons are generated in many
brain regions. Developing neurons that fail to make connections
with appropriate trophic factor producing target cells are deprived
of necessary neurotrophic factors and die. Those neurons that
establish connections survive and function properly (e.g. NGF; see
Campenot, R. B. and MacInnis, B. L. "Retrograde transport of
neurotrophins: fact and function", J Neurobiol 58: 217-229 (2004)).
Neurotrophic factors are also capable of promoting the re-growth of
damaged neurons and their processes both in vitro and in animal
models (see Lad, S. P. et al., "Individual and combined effects of
TrkA and p75NTR nerve growth factor receptors: A role for the high
affinity receptor site", J Biol Chem 278: 24808-24817 (2003a) and
Lad, S. P. et al., "Nerve growth factor: structure, function and
therapeutic implications for Alzheimer's disease", Curr Drug
Targets CNS Neurol Disord 2: 315-334 (2003b)). Identifying
neurotrophic factors with the right combination of protective and
restorative actions and developing effective strategies for drug
delivery have profound therapeutic implications for Parkinson's
disease, Alzheimer's disease, Huntington's disease and other
degenerative processes in the brain (including those induced by
brain injury).
[0006] Glial cell line-derived neurotrophic factor (GDNF) is a
trophic factor shown to dramatically protect and enhance the
function of dopamine neurons in vitro and in vivo in rodents and
monkeys (Beck, K. D., et al., "Mesencephalic dopaminergic neurons
protected by GDNF from axotomy-induced degeneration in the adult
brain", Nature, 373:339-41 (1995); and Bjorklund, A., et al.,
"Towards a neuroprotective gene therapy for Parkinson's disease:
use of adenovirus, AAV and lentivirus vectors for gene transfer of
GDNF to the nigrostriatal system in the rat Parkinson model", Brain
Res., 886:82-98 (2000), Gash, D. M., et al., "Functional Recovery
in Parkinsonian Monkeys Treated with GDNF, Nature", 380:252-255
(1996); Grondin, R., et al., "Striatal GDNF Infusion Promotes
Structural and Functional Recovery in Advanced Parkinsonian
Monkeys. Brain", 125:2191-2201 (2002); Grondin, R., et al., "GDNF
Increases Stimulus-evoked Dopamine Release and Motor Speed in Aged
Rhesus Monkeys", J Neurosci., 23:1974-1980 (2003); Hebert M. A., et
al., "Functional Effects of GDNF in Normal Rat Striatum:
Presynaptic Studies Using In Vivo Electrochemistry and
Microdialysis", J. Pharm. Exp. Ther., 279:1181-1190 (1996); Hebert
M. A. and Gerhardt, G. A., "Behavioral and Neurochemical Effects of
Intranigral GDNF Administration on Aged Fischer 344 Rats", J.
Pharm. Exp. Ther., 282:760-768 (1997); Hou, J. G. G., et al.,
"Glial Cell line-Derived Neurotrophic Factor Exerts Neurotrophic
Effects on Dopaminergic Neurons In Vitro and Promotes Their
Survival And Regrowth After Damage by 1-Methyl-4-Phenylpyridinium",
J. Neurochem., 66:74-82 (1996); Kordower, J. H., et al.,
"Clinicopathological Findings Following Intraventricular
Glial-Derived Neurotrophic Factor Treatment in a Patient with
Parkinson's Disease", Ann Neurol., 46(3):419-424 (1999); Kordower,
J. H., et al., "Neurodegeneration Prevented by Lentiviral Vector
Delivery of GDNF in Primate Models of Parkinson's Disease",
Science, 290:767-773 (2000); Palfi, S., et al., "Lentivirally
Delivered Glial Cell Line-derived Neurotrophic Factor Increases the
Number of Striatal Dopaminergic Neurons in Primate Models of
Nigrostriatal Degeneration", J Neurosci., 22:4942-4954 (2002);
Tomac, A., et al., "Protection and Repair of the Nigrostriatal
Dopaminergic System by GDNF In Vivo", Nature, 373:335-339
(1995)).
[0007] The current standard treatment, levodopa, is palliative and
does not prevent the relentless progression of Parkinson's
degeneration. GDNF exerts effects on dopamine neurons that slow the
process of Parkinson's disease and even reverses some of the
degenerative changes. Preclinical studies conducted to date suggest
that GDNF exerts at least three general trophic actions on dopamine
neurons in the substantia nigra: pharmacological upregulation,
restoration and neuroprotection. With regard to pharmacological
upregulation, GDNF upregulates dopaminergic functions, such as
increasing the evoked release of dopamine (Gerhardt, G. A. et al.,
"GDNF improves dopamine function in the substantia nigra but not
the putamen of unilateral MPTP-lesioned rhesus monkeys", Brain Res
817: 163-171 (1999) and Grondin et al., 2003). It also appears to
modulate the phosphorylation of TH (Salvatore, M et al. "Striatal
GDNF administration increases tyrosine hydroxylase phosphorylation
in the rat striatum and substantia nigra". J Neurochem. 90:245-54.,
(2004)). With regard to restoration, GDNF increases the number of
neurons expressing the dopamine markers TH and DAT in the
substantia nigra (Gash et al., 1996; Kordower et al., 2000; and
Grondin et al., 2002). This suggests that one trophic action is to
stimulate recovery of injured/quiescent nigral neurons. Supporting
this interpretation is the consistent observation that GDNF
promotes increases in dopamine neuron perikaryal size and the
number of neurites. With regard to neuroprotection, nigrostriatal
administration of GDNF either shortly before or following a
neurotoxic challenge (e.g. 6-OHDA, methyl-amphetamine or MPTP)
protects dopamine neurons from injury in rodents and nonhuman
primates (Kordower et al., 2000 and Fox, C. M., "Neuroprotective
effects of GDNF against 6-OHDA in young and aged rats", Brain Res
896:56-63 (2001)).
[0008] Accordingly, GDNF therapy is expected to be helpful in the
treatment of nerve damage caused by conditions that compromise the
survival and/or proper function of one or more types of nerve
cells. Such nerve damage may occur from a wide variety of different
causes. Nerve damage may occur to one or more types of nerve cells
by, for example: (1) physical injury, which causes the degeneration
of the axonal processes and/or nerve cell bodies near the site of
injury; (2) temporary or permanent cessation of blood flow to parts
of the nervous system, as in stroke; (3) intentional or accidental
exposure to neurotoxins, such as chemotherapeutic agents (e.g.,
cisplatinum) for the treatment of cancer or dideoxycytidine (ddC)
for the treatment of AIDS; (4) chronic metabolic diseases, such as
diabetes or renal dysfunction; or (5) neurodegenerative diseases
such as Parkinson's disease, Alzheimer's disease, and Amyotrophic
Lateral Sclerosis (ALS), which result from the degeneration of
specific neuronal populations.
[0009] GDNF therapy may be particularly helpful in the treatment of
neurodegenerative conditions involving the degeneration of the
dopaminergic neurons of the substantia nigra, such as Parkinson's
disease. The expected impact of GDNF therapy is not just to produce
an increase in the dopaminergic neurotransmission at the
dopaminergic nerve terminals in the striatum (which will result in
a relief of the symptoms), but also to slow down, or even stop, the
progression of the degenerative processes and to repair the damaged
nigrostriatal pathway and restore its function. GDNF may also be
used in treating other forms of damage to or improper function of
dopaminergic nerve cells in human subjects. Such damage or
malfunction may occur in schizophrenia and other forms of
psychosis. The only current treatments for such conditions are
symptomatic and require drugs which act upon dopamine receptors or
dopamine uptake sites, consistent with the view that the improper
functioning of the dopaminergic neurons which innervate these
receptor-bearing neuronal populations may be involved in the
disease process.
[0010] However, initial clinical trials involving ventricular
delivery of GDNF showed no statistically significant
differentiation of the placebo and active treatment groups (Nutt,
J. G. et al. "Randomized, double-blind trial of glial cell
line-derived neurotrophic factor (GDNF) in PD", Neurology 60: 69-73
(2003)), perhaps because insufficient amounts of GDNF reached
critical target sites from the CSF (Ai, Y. et al., "Intraputamenal
Infusion in Aging Rhesus Monkeys: Distribution and Dopaminergic
Effects", J Comp Neurol 461: 250-26125 (2003); and Kordower, J. H.,
et al. (2000)). In addition, a phase 2 trial evaluating
intraputamenal delivery of glial cell line-derived neurotrophic
factor (GDNF) for the treatment of Parkinson's disease failed to
achieve its primary end point, a 25% improvement on the Unified
Parkinson Disease Rating Scale (UPDRS) motor score "off" medication
after six months of treatment (Lang, A. E. et al., "Randomized
controlled trial of intraputamenal glial cell line-derived
neurotrophic factor infusion in Parkinson's disease", Ann Neurol
59:459-466 (2006)). There are strong indications from studies in
rhesus monkeys using the same delivery system and protocol followed
in the phase 2 study that drug bioavailability significantly
contributed to the failure of the trial (Salvatore et al., "Point
source concentration of GDNF may explain failure of phase II
clinical trial". Exp Neurol 202(2):497-505 (2006)). The
concentration of GDNF around the catheter tip and limited diffusion
into surrounding brain parenchyma was limited to a brain volume
representing 2-9% of the human putamen. Thus GDNF distribution in
the phase 2 trial was likely limited to a small brain region, and
could affect only a limited segment of the brain undergoing
parkinsonian degeneration.
[0011] Successful trophic factor therapy requires site-specific
delivery and distribution of the trophic factor throughout the
target tissue (the putamen for Parkinson's disease). The blood
brain barrier effectively blocks entry from blood borne proteins,
including trophic factors. Infusions into the cerebrospinal fluid
are not effective in humans because of brain size and may produce
unwanted side effects by stimulating other trophic factor
responsive populations such as sensory neurons.
[0012] In addition to focal delivery into the appropriate site, the
delivery must be tightly regulated. Regardless of the method used
to deliver GDNF (i.e., direct infusion, stem cells, encapsulated
cells, gene therapy) prolonged elevated levels of GDNF in the brain
outside of the target area may produce adverse side-effects.
Circulating antibodies to GDNF are one possible outcome and it is
quite typical to find antibodies to endogenous proteins used
therapeutically (e.g. beta interferon and insulin, see Durelli, L.,
et al., "Anti-interferon antibodies in multiple sclerosis:
molecular basis and their impact on clinical efficacy", Front
Biosci 9: 2192-2204 (2004) and Stoever, J. A. et al., "Inhaled
insulin and insulin antibodies: a new twist to an old debate",
Diabetes Technol Ther 4: 157-161 (2002)). The effects of
circulating GDNF antibodies are not known. Focal Purkinje cell
lesions have been reported in some monkeys receiving high levels of
GDNF in a toxicology study (see Sherer, T. B., et al., Movement Dis
21:136-141 (2006)). Another possible side-effect is aberrant
sprouting and tyrosine hydroxylase downregulation of the
nigrostriatal dopaminergic pathway in rats exposed to high GDNF
levels from viral vector gene transfer (Georgievska, B., et al.
"Neuroprotection in the rat Parkinson model by intrastriatal GDNF
gene transfer using a lentiviral vector", Neuroreport 13: 75-82
(2002)). Also, increased neuronal death has been reported in rats
with elevated GDNF from viral vector gene transfer in a stroke
model (Arvidsson, A. et al., "Elevated GDNF levels following viral
vector-mediated gene transfer can increase neuronal death after
stroke in rats", Neurobiol Dis 14: 542-556, (2003)).
[0013] While GDNF has not met the criteria for clinical efficacy in
the two phase 2 trials conducted to date (Nutt et al., 2003; Lang
et al., 2006), it appears to be the most potent dopaminergic
trophic factor found to date. Thus, the ideal drug for treating
Parkinson's disease and other neurodegenerative processes in the
brain would possess the positive trophic actions of GDNF. Delivery
could be targeted to the appropriate brain area by any of a number
of methods including direct infusion, viral vectors or even nasal
sprays. In particular, biologically active peptides with trophic
actions may offer many of the desired properties. To date, such
biologically active peptides have not been identified.
[0014] A crude peptide extract from the brain cerebrolysin has been
tested in human studies, with modest effects reported (Lukhanina,
E. P. et al., "Effect of cerebrolysin on the
electroencephalographic indices of brain activity in Parkinson's
disease", Zh Nevrol Psikhiatr Im S S Korsakova 104: 54-60 (2004)).
Three small molecule compounds have also been tested in Parkinson's
disease patients: the tripeptide glutathione, tocopherol, and
Coenzyme Q10 (Weber, C. A., et al. "Antioxidants, supplements and
Parkinson's disease", Ann Pharmacother 40: 935-938 (2006)). The
three small molecule compounds also appear to have only minor
benefits for patients.
[0015] Consequently, there continues to exist a long-felt need for
effective agents and methods for the treatment and prevention of
brain diseases and injuries that result in dopaminergic
deficiencies. Accordingly, it is an object of the present invention
to provide agents for treating and preventing such diseases and
injuries in a subject, comprising novel amidated GDNF-derived
peptides that have dopaminergic trophic factor activity. This and
other such objectives will be readily apparent to the skilled
artisan from this disclosure.
SUMMARY OF THE INVENTION
[0016] In one embodiment, the present invention provides a
composition comprising at least one of the following peptides: (a)
a purified Amidated Dopamine Neuron Stimulating peptide (ADNS
peptide) comprising the amino acid sequence ERNRQAAAANPENSRGK-amide
(SEQ ID NO: 2); (b) a purified ADNS peptide comprising the amino
acid sequence FPLPA-amide (SEQ ID NO: 3); and (c) a purified ADNS
peptide comprising the amino acid sequence PPEAPAEDRSL-amide (SEQ
ID NO: 4). In another embodiment, the present invention provides a
method for treating a brain disease or injury resulting in
dopaminergic deficiencies, comprising administering a
pharmaceutically effective amount of the composition to a subject
in need thereof, wherein said composition further comprises at
least one of a pharmaceutically acceptable vehicle, excipient, and
diluent. Preferably, the subject is a mammal, and most preferably,
the subject is human.
BRIEF DESCRIPTION OF THE FIGURES
[0017] FIG. 1 depicts the nucleotide sequence (top strand) and
amino acid sequence (bottom strand) of mature human GDNF (SEQ ID
NO: 5 and SEQ ID NO: 1).
[0018] FIG. 2 depicts the post-translational processing of splice
form 1 of human GDNF. Sequences from top to bottom are: SEQ ID NO:
6, SEQ ID NO: 7, SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID
NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO: 3, SEQ ID NO:4,
and SEQ ID NO: 2.
[0019] FIG. 3 depicts the precursor segments of the ADNS peptides
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2), FPLPA-amide (SEQ ID NO:3),
and PPEAPAEDRSL-amide (SEQ ID NO:4). From top to bottom SEQ ID NO:
8, SEQ ID NO: 14, and SEQ ID NO:15.
[0020] FIG. 4 depicts the average K.sup.+-evoked release of
dopamine in Fischer 344 rats treated with ADNS peptides.
[0021] FIG. 5 depicts the increase in major metabolites of dopamine
in Fischer 344 rats treated with ADNS peptides.
[0022] FIG. 6 depicts the increased survival of dopamine neurons in
cell cultures treated with ADNS peptides.
[0023] FIGS. 7A and B depict the results of in vivo microdialysis
used to investigate the dynamics of dopamine release in the basal
ganglia of the right putamen following treatment with ADNS
peptides.
[0024] FIGS. 8A-F depict the histopathological response to the
injection of ADNS peptides in the nigral region using standard
histochemical techniques.
[0025] FIGS. 9A-D depict a series of photomicrographs evaluating
the substantia nigra compacta (SNc) containing the population of
dopamine neurons that degenerates in Parkinson's disease after
treatment with ADNS peptides.
[0026] FIGS. 10A and B depict the sequence origin and homology of
dopamine neuron stimulating peptide-11 (DNSP-11).
[0027] FIGS. 11A-D depict the neurotropic effects of DNSP-11 and
GDNF on mesencephalic (A and B) and MN9D (C and D) dopaminergic
cells.
[0028] FIGS. 12A-C depict the effects of DNSP-11 in normal (A) and
unilateral 6-OHDA-lesioned (B and C) rats.
[0029] FIG. 13 depicts the interactions of DNSP-11 with protein
partners.
[0030] FIG. 14 depicts the gel filtration analysis of the
interaction between GAPDH and GDNF.
[0031] FIGS. 15A-C depict the solubility and stability of DNSP-11
at various storage and experimental conditions.
[0032] FIG. 16 shows the effects of citrate vehicle or DNSP-11 on
resting levels of DOPAC one month after a single infusion.
[0033] FIG. 17 shows the broad distribution of DNSP-11 in the rat
substantia nigra region of the midbran within 30 minutes of DNSP-11
injection (panels A-F).
[0034] FIG. 18A-B shows the DNSP-11 increased State III oxygen
consumption vs. vehicle in both the SN and striatum, 28 days post
bilateral intrnigral injections (*p<0.05 vs control, two-tailed,
unparired tests). (A) Substantia nigra 28 days; (B) Striatum 28
days.
[0035] FIG. 19A-B demonstrates that DNSP-11 produced a significant,
about 50%, decrease in apomorphine-induced rotational behavior (A)
and significantly increased levels of dopamine and the dopamine
metabolite, DOPAC, by about 100% in the substantia nigra (B).
DETAILED DESCRIPTION OF THE INVENTION
[0036] Human glial cell line-derived neurotrophic factor (hGDNF) is
synthesized as a precursor that is processed and secreted as a
mature protein of 134 amino acids. Mature human GDNF has the amino
acid sequence depicted in FIG. 1 (SEQ ID NO:1).
[0037] The present invention is related to the realization that
human GDNF (splice form 1) precursor protein conforms to a rather
exacting sequence profile characteristic of neuropeptide precursor
proteins. GDNF is expressed in at least three isoforms that result
from alternative splicing of mRNA. Proteins expressed from these
RNA splice variants differ in their N-terminal regions (see NCBI
entry NP 000505 for isoform 1; NCBI entry NP 964701 for isoform 2;
and NCBI entry NP 954704 for isoform 3). Isoforms 1 and 2 are
secretory protein precursors with N-terminal signal peptides.
Isoform 3 is likely a nuclear-targeted protein with a nuclear
localization signal (NLS), but no signal peptide. The three
isoforms are differentially expressed, apparently under regulatory
control.
[0038] All of the isoforms contain the sequence that is considered
mature GDNF with "full biological activity" (residues 78-211 in
isoform 1). In fact, recombinant proteins further truncated at the
N-terminus are purported to have the "full biological activity".
From the fact that three separate precursors of the same GDNF
molecule are expressed under separate regulation, two with signal
peptides and the third with a probable nuclear localization signal,
suggests that there are both nuclear and cell surface receptors for
GDNF.
[0039] The separately regulated expression of two different
secretory isoforms (isoforms 1 and 2) suggests a biologically
significant function for the different N-terminal sequences of the
isoforms. The conventional wisdom is that residues 20-77 of isoform
1 precursor constitute a "domain propeptide". The present invention
provides a new interpretation of the importance of the 20-77
"domain propeptide" region of isoform 1 precursor. The "domain
propeptide" segment of isoform 1 precursor is the metabolic
precursor of two small amidated peptides, according to well
established enzymatic pathways for release of peptide amide
hormones and neuropeptides from their precursor proteins. The two
small amidated peptides are FPLPA-amide (SEQ ID NO: 3) and
PPEAPAEDRSL-amide (SEQ ID NO: 4).
[0040] Furthermore, a third small amidated peptide,
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2), may be released from
consensus enzymatic processing of residues 88-110 of the isoform 1
precursor. This consensus peptide amide precursor occupies the
N-terminal sequence of "mature GDNF", which is presumably not
critical or at least includes residues that are not critical for
biological activity, according to the patent literature. The
isoform 2 precursor contains the sequence FPLPA (SEQ ID NO: 16),
but does not contain the amidation signal (GKR, residues 25-27) in
the case of Isoform 1 precursor. Isoform 2 is not, in other words,
a potential precursor of FPLPA-amide (SEQ ID NO: 3) according to
known enzymatic pathways. Isoform 3 does not contain the sequence
FPLPA at all, so likewise can not be a metabolic precursor of
FPLPA-amide (SEQ ID NO: 3). Both Isoforms 1 and 2 are consensus
precursors of ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2), but isoform 3
is not.
[0041] Thus, human GDNF isoform 1 is a secretory protein that can
potentially yield three small amidated peptides by consensus
enzymatic pathways known to release peptide amide hormones and
neuropeptides from their known precursor proteins. This is a rare
combination of enzymatic processing motifs and strongly suggests
that GDNF isoform 1 precursor is the metabolic precursor of up to
three small ADNS peptides, in addition to the larger C-terminal
domain that is widely supposed to posses the "full biological
activity" of GDNF. C-terminal amidation in natural peptides is
highly correlated with receptor mediated signal transduction: about
half of the known peptide hormones and neuropeptides and C-terminal
amidation is rare and almost unknown among other peptides of
biological origin.
[0042] Animal studies with synthetic peptides corresponding to the
consensus products of Isoform 1 precursor protein are consistent
with some or all of these peptides being biologically active and
involved in regulation of dopamine metabolism. This is to be
expected from a protein that yields multiple biologically active
regulatory peptides in a fixed molar ratio. The fact that the
different Isoforms of GDNF precursor protein are consensus
precursors of different combinations of amidated peptides in
addition to GDNF, suggests a reason for differential expression of
three separate isoforms (in addition to differential secretory and
nuclear routing).
[0043] According to this model, splice form 1 of human GDNF may be
post-translationally processed in vivo to yield three small
amidated peptides, as indicated in FIG. 2. These small amidated
peptides may mediate some or all of the biological effects of GDNF.
The present invention is based on the unexpected discovery that
these small amidated fragments of the mature GDNF protein retain
the biological activity of GDNF.
[0044] Thus, the ADNS peptides of the present invention include
these three small amidated peptides, which are represented by the
amino acid sequences ERNRQAAAANPENSRGK-amide; FPLPA-amide; and
PPEAPAEDRSL-amide (SEQ ID NOs: 2, 3, and 4, respectively).
[0045] The ADNS peptides of the present invention are promising
candidates for treatment and prevention of neurodegenerative
conditions involving dopaminergic deficiencies, such as Parkinsons
disease, age-associated motor and cognitive slowing, and other
diseases and injuries to the brain. The small ADNS peptides are
easily within the range of synthetic production methods, so that
the molecules could be subjected to rigorous structure-activity
studies to optimize pharmacological activities and biostability. In
addition, as the difficulties in delivering GDNF clinically may
well be related to the fact that recombinant GDNF is not properly
processed into active forms, the small ADNS peptides may overcome
some of these difficulties. Finally, small peptides are generally
much less antigenic than proteins and can be synthesized free of
the trace host protein contaminants always present in recombinant
proteins.
[0046] The small ADNS peptides of the present invention include
biologically active synthetic or recombinant ADNS peptides, ADNS
peptides produced from GDNF, biologically active ADNS peptide
variants (including insertion, substitution, and deletion
variants), and chemically modified derivatives thereof. Also
included are biologically active ADNS peptide variants that are
substantially homologous to any one of the ADNS peptides having the
amino acid sequence set forth in SEQ ID NOs:2, 3, or 4.
[0047] The term "biologically active" as used herein means that the
ADNS peptide demonstrates similar neurotrophic properties, but not
necessarily all of the same properties, and not necessarily to the
same degree, as the GDNF protein having the amino acid sequence set
forth in SEQ ID NO:1. The selection of the particular neurotrophic
properties of interest depends upon the use for which the ADNS
peptide is being administered. The ADNS peptides are biologically
active and demonstrate dopaminergic neuron survival characteristics
similar to that demonstrated by the combination of amide peptides
represented by SEQ ID NOs:2, 3, or 4 using the evaluation of
dopamine neuron survival in cultures of newborn rat midbrain
dopamine neurons as an exemplary bioassay, as discussed in the
examples below.
[0048] The term "substantially homologous", as used herein, means a
degree of sequence homology to any one of the ADNS peptides having
the amino acid sequences set forth in SEQ ID NOs:2, 3, or 4 that is
preferably at least 70%, most preferably at least 80%, and even
more preferably at least 90% or even 95%.
[0049] As used herein, the term "ADNS peptide," "peptide amide," or
"amidated peptide" means a peptide comprising the group
--CONH.sub.2 at the C-terminal end. This amidation occurs in vivo,
once the peptides are formed by the enzyme, peptidylglycine
amidating monooxygenase (PAM). The ADNS peptides of the present
invention can be readily obtained in a variety of ways, including,
without limitation, recombinant expression, purification from
natural sources, and/or chemical synthesis. Preferably, the ADNS
peptides can be chemically synthesized by commercial venders. The
ADNS peptides used in the present examples were synthesized using
tBOC chemistry and at a single scale range (which generates a
theoretical crude yield of 500-1,000 mg for a 10-20 mer
respectively), by the Keck Biotechnology Resource Laboratory at
Yale University (New Haven, Conn.).
[0050] ADNS peptide pharmaceutical compositions typically include a
therapeutically effective amount of at least one of a ADNS peptide
represented by SEQ ID NOs:2, 3, and 4 in admixture with one or more
pharmaceutically and physiologically acceptable formulation
materials. Suitable formulation materials include, but are not
limited to, antioxidants, preservatives, coloring, flavoring and
diluting agents, emulsifying agents, suspending agents, solvents,
fillers, bulking agents, buffers, delivery vehicles, diluents,
excipients and/or pharmaceutical adjuvants. For example, a suitable
vehicle may be water for injection, physiological saline solution,
or artificial cerebrospinal fluid (CSF), possibly supplemented with
other materials common in compositions for parenteral
administration. Neutral buffered saline or saline mixed with serum
albumin are further exemplary vehicles.
[0051] The primary solvent in a vehicle may be either aqueous or
non-aqueous in nature. In addition, the vehicle may contain other
pharmaceutically-acceptable excipients for modifying or maintaining
the pH, osmolarity, viscosity, clarity, color, sterility,
stability, rate of dissolution, or odor of the formulation.
Similarly, the vehicle may contain still other
pharmaceutically-acceptable excipients for modifying or maintaining
the stability, rate of dissolution, or rate of release of ADNS
peptide, or for promoting the absorption or penetration of ADNS
peptide across the blood-brain barrier. Such excipients are those
substances usually and customarily employed to formulate dosages
for parenteral administration in either unit dose or multi-dose
form or for direct infusion into the CSF by continuous or periodic
infusion from an implanted pump.
[0052] Once the therapeutic composition has been formulated, it may
be stored in sterile vials as a solution, suspension, gel,
emulsion, solid, or dehydrated or lyophilized powder. Such
formulations may be stored either in a ready to use form or in a
form, e.g., lyophilized, requiring reconstitution prior to
administration.
[0053] The optimal pharmaceutical formulation will be determined by
one skilled in the art depending upon the route of administration
and desired dosage. See for example, Remington's Pharmaceutical
Sciences, 18th Ed. (1990, Mack Publishing Co., Easton, Pa. 18042)
pages 1435-1712 the disclosure of which is hereby incorporated by
reference. The composition may also involve particulate
preparations of polymeric compounds such as polylactic acid,
polyglycolic acid, etc. or into liposomes. Hylauronic acid may also
be used, and this may have the effect of promoting sustained
duration in the circulation. Such compositions may influence the
physical state, stability, rate of in vivo release, and rate of in
vivo clearance of the present proteins and derivatives.
[0054] Other effective administration forms, such as parenteral
slow-release formulations, inhalant mists, orally active
formulations, or suppositories, are also envisioned. Preferred ADNS
peptide pharmaceutical compositions are formulated for parenteral
administration, e.g., intracerebroventricular injection. Such
parenterally administered therapeutic compositions are typically in
the form of a pyrogen-free, parenterally acceptable aqueous
solution comprising ADNS peptide in a pharmaceutically acceptable
vehicle. One preferred vehicle is physiological saline.
[0055] It is also contemplated that certain formulations containing
ADNS peptides are to be administered orally. ADNS peptide which is
administered in this fashion may be encapsulated and may be
formulated with or without those carriers customarily used in the
compounding of solid dosage forms. The capsule may designed to
release the active portion of the formulation at the point in the
gastrointestinal tract when bioavailability is maximized and
pre-systemic degradation is minimized. Additional excipients may be
included to facilitate absorption of ADNS peptide.
[0056] Diluents, flavorings, low melting point waxes, vegetable
oils, lubricants, suspending agents, tablet disintegrating agents,
and binders may also be employed.
[0057] It is further contemplated that formulations containing ADNS
peptides are to be administered nasally. As used herein, nasally
administering or nasal administration includes administering the
formulation containing ADNS to the mucous membranes of the nasal
passage or nasal cavity of the patient. Formulations for nasal
administration include a pharmaceutically effective amount of the
peptides prepared by well-known methods, to be administered, for
example, as a nasal spray, drop, suspension, gel, ointment, cream
or powder. Administration of the ADNS-containing formulation may
also take place using a nasal tampon, or nasal sponge.
[0058] The ADNS peptides may be administered parenterally via a
subcutaneous, intramuscular, intravenous, transpulmonary,
transdermal, intrathecal or intracerebral route. ADNS peptides that
do not cross the blood-brain barrier may be given directly
intracerebrally or otherwise in association with other elements
that will transport them across the barrier. It is preferred that
the ADNS peptide is administered intracerebroventricularly or into
the brain or spinal cord subarachnoid space. ADNS peptides may also
be administered intracerebrally directly into the brain parenchyma.
Slow-releasing implants in the brain containing the neurotrophic
factor embedded in a biodegradable polymer matrix can also deliver
ADNS peptides. ADNS peptides may be administered extracerebrally in
a form that has been modified chemically or packaged so that it
passes the blood-brain barrier, or it may be administered in
connection with one or more agents capable of promoting penetration
ADNS peptide across the barrier. For example, a conjugate of NGF
and monoclonal anti-transferrin receptor antibodies has been shown
to be transported to the brain via binding to transferrin
receptors. To achieve the desired dose of ADNS peptide, repeated
daily or less frequent injections may be administered, or truncated
ADNS peptide may be infused continuously or periodically from a
constant- or programmable-flow implanted pump. The frequency of
dosing will depend on the pharmacokinetic parameters of ADNS
peptide as formulated, and the route of administration.
[0059] Regardless of the manner of administration, the specific
dose is typically calculated according to body weight or body
surface area. For diseases involving the brain, the specific dose
is typically calculated according to the approximate brain weight
of the subject, which also may be estimated based on body weight or
body surface area. Further refinement of the calculations necessary
to determine the appropriate dosage for treatment involving each of
the above mentioned formulations is routinely made by those of
ordinary skill in the art, especially in light of the dosage
information and assays disclosed herein. Appropriate dosages may be
ascertained through use of the established assays for determining
dosages utilized in conjunction with appropriate dose-response
data. The final dosage regimen involved in a method of treating a
specific condition will be determined by the attending physician,
considering various factors which modify the action of drugs, e.g.,
the age, condition, body weight, sex and diet of the subject, the
severity of any infection, time of administration and other
clinical factors.
[0060] ADNS peptides of the present invention may also be employed,
alone or in combination with other growth factors in the treatment
of nerve disease. For example, ADNS peptides may be used in
treating some forms of nerve disease in combination with nerve
growth factor. In addition, other factors or other molecules,
including chemical compositions, may be employed together with ADNS
peptides. In the treatment of Parkinson's disease, it is
contemplated that ADNS peptide be used by itself or in conjunction
with the administration of Levodopa, wherein the ADNS peptide would
enhance the production of endogenous dopamine and the neuronal
uptake of the increased concentration of dopamine.
[0061] As stated above, it is also contemplated that additional
neurotrophic or neuron nurturing factors will be useful or
necessary to treat some neuronal cell populations or some types of
injury or disease. Other factors that may be used in conjunction
with ADNS peptides include, but are not limited to: mitogens such
as insulin, insulin-like growth factors, epidermal growth factor,
vasoactive growth factor, pituitary adenylate cyclase activating
polypeptide, interferon and somatostatin; neurotrophic factors such
as brain derived neurotrophic factor, neurotrophin-3,
neurotrophin-4/5, neurotrophin-6, insulin-like growth factor,
ciliary neurotrophic factor, acidic and basic fibroblast growth
factors, fibroblast growth factor-5, transforming growth
factor-.beta., cocaine-amphetamine regulated transcript (CART) and
mature GDNF; and other growth factors such as epidermal growth
factor, leukemia inhibitory factor, interleukins, interferon, and
colony stimulating factors; as well as molecules and materials
which are the functional equivalents to these factors.
[0062] It is envisioned that the continuous administration or
sustained delivery of a ADNS peptide may be advantageous for a
given treatment. While continuous administration may be
accomplished via a mechanical means, such as with an infusion pump,
it is contemplated that other modes of continuous or near
continuous administration may be practiced. For example, chemical
derivatization may result in sustained release forms of the protein
which have the effect of continuous presence in the blood stream,
in predictable amounts, based on a determined dosage regimen. Thus,
ADNS peptides of the present invention include ADNS peptides
derivatized to effectuate such continuous administration.
[0063] ADNS peptide cell therapy, e.g., intracerebral implantation
of cells producing ADNS peptides, is also contemplated. This
embodiment of the present invention may include implanting into
subject's cells which are capable of synthesizing and secreting a
biologically active form of the ADNS peptides of the present
invention. Such ADNS peptide producing-cells may be cells which do
not normally produce a neurotrophic factor but have been modified
to produce ADNS peptides, or they could be cells whose ability to
produce GDNF has been augmented by transformation with a
polynucleotide suitable for the expression and secretion of ADNS
peptides. In order to minimize a potential immunological reaction
in subjects, it is preferred that the cells be of human origin.
[0064] Implanted cells may be encapsulated to avoid infiltration of
the cells into brain tissue. Human or non-human animal cells may be
implanted in subjects in biocompatible, semi-permeable polymeric
enclosures or membranes to allow release of an ADNS peptide, but
that prevent destruction of the cells by the subject's immune
system or by other detrimental factors from the surrounding tissue.
Alternatively, the subject's own cells, transformed ex vivo to
produce ADNS peptides, could be implanted directly into the subject
without such encapsulation.
[0065] The methodology for the membrane encapsulation of living
cells is familiar to those of ordinary skill in the art, and the
preparation of the encapsulated cells and their implantation in
subjects may be accomplished. See for example, U.S. Pat. Nos.
4,892,538; 5,011,472; and 5,106,627, the disclosures of which are
hereby incorporated by reference. A system for encapsulating living
cells is also described in PCT Application WO 91/10425 of Aebischer
et al., specifically incorporated herein by reference. See also,
PCT Application WO 91/10470 of Aebischer et al.; Winn et al.,
Exper. Neurol., 113:322-329, 1991; Aebischer et al., Exper.
Neurol., 111.269-275, 1991; and 35 Tresco et al., ASAIO, 38:17-23,
1992, the disclosures of which are hereby incorporated by
reference.
[0066] ADNS peptide gene therapy in vivo is also envisioned,
wherein a nucleic acid sequence encoding an ADNS peptide is
introduced directly into the subject. For example, a nucleic acid
sequence encoding an ADNS peptide is introduced into target cells
via local injection of a nucleic acid construct with or without an
appropriate delivery vector, such as an adeno-associated viral
vector. Alternative viral vectors include, but are not limited to,
retrovirus, adenovirus, herpes simplex virus and papilloma virus
vectors. Physical transfer may be achieved in vivo by local
injection of the desired nucleic acid construct or other
appropriate delivery vector containing the desired nucleic acid
sequence, liposome-mediated transfer, direct injection (naked DNA),
receptor-mediated transfer (ligand-DNA complex), or microparticle
bombardment (gene gun). It should be noted that the ADNS peptide
formulations described herein may be used for veterinary as well as
human applications and that the term "subject" should not be
construed in a limiting manner. In the case of veterinary
applications, the dosage ranges should be the same as specified
above.
[0067] As a means of further characterizing the ADNS peptides of
the present invention, antibodies can be developed which bind to
the ADNS peptides. One of ordinary skill in the art can use
well-known, published procedures to obtain monoclonal and
polyclonal antibodies, or recombinant antibodies, which
specifically recognize and bind to the various ADNS peptides of the
present invention.
[0068] Other aspects and advantages of the present invention will
be understood upon consideration of the following illustrative
examples. The examples are not to be construed in any way as
limiting the scope of this invention.
EXAMPLES
Example 1: BLAST Analysis
[0069] The three hypothetical precursor segments
(RRERNRQAAAANPENSRGKGRR (SEQ ID NO: 5); FPLPAGKR (SEQ ID NO: 8);
and KRPPEAPAEDRSLGRR (SEQ ID NO: 7); see FIG. 3) were subjected to
BLAST searches for short, nearly identical sequences.
RRERNRQAAAANPENSRGKGRR (SEQ ID NO: 15) is present in GDNF splice
forms 1 and 2. There are some sequence variations by species, but
consensus post-translational processing signals are maintained
across species. FPLPAGKR (SEQ ID NO: 8) was found to be invariant
in the available GDNF splice form 1 sequences, but does not occur
in splice forms 2 and 3. KRPPEAPAEDRSLGRR (SEQ ID NO: 7) scored
hits in splice form 1, but not in the other GDNF splice forms.
There are some sequence variations by species, but consensus
processing signals are maintained across species. Thus, these ADNS
peptides are unique to mostly splice form 1 of GDNF and not other
splice forms of the pre pro GDNF.
Example 2: Synthesis of ADNS Peptides
[0070] Three peptides, designated GER9263, GER9264, and GDR9265
(see Table 1, below) were synthesized by Keck Biotechnology
Resource Laboratory, Yale University New Haven, Conn. Synthetic
peptides can be made routinely up to 40 residues and often,
depending on sequence, up to 70 residues by this facility. All
peptides were separated and purified on a preparative C-18 or C-4
RP-HPLC system and delivered as a lyophilized material. Yields for
normal peptides under 40 residues were "guaranteed" at 50 mg or
more and at 90+% purity. Yields and purity are often higher,
varying with the peptide sequence and length. All peptides made in
the Keck facility at the 0.5 mmole scale are done by tBOC chemistry
and at a single scale range (which generates a theoretical crude
yield of 500-1,000 mg for a 10-20 mer respectively). The purified
peptides were characterized by analytical RP-HPLC, amino acid
analysis, and FAB mass spectroscopy.
TABLE-US-00001 TABLE 1 ADNS peptides Peptide Sequence GER9263
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2) GER9264 FPLPA-amide (SEQ ID
NO: 3) GDR9265 PPEAPAEDRSL-amide (SEQ ID NO: 4)
Example 3: Dopaminergic Activity of ADNS Peptides in Fischer 344
Rats
[0071] Experiments were performed to test the effects of the three
ADNS peptides (GER9263, GER9264, and GDR9265) on dopaminergic
activity in normal young adult male Fischer 344 rats. The peptides
were combined in a 1:1:1 ratio. There were three test groups with
six animals per group: vehicle (citrate buffer), vehicle plus 30
.mu.g peptide mixture, and vehicle plus 100 .mu.g peptide mixture.
The vehicle or vehicle plus peptide solutions were steriotaxically
injected in equal portions into two sites each in the right
substantia nigra.
[0072] One month after drug administration, the basal levels of
dopamine and dopamine metabolites were measured by microdialysis in
the right striatum. Potassium and amphetamine evoked release of
dopamine were also evaluated.
[0073] While basal levels of dopamine were not significantly
altered in the striatum, average K.sup.+-evoked release of dopamine
increased by over 50% (FIG. 4). Average amphetamine-evoked release
was more variable, but ranged from about 30% for 100 .mu.g to about
45% for 30 .mu.g. While basal dopamine levels were about the same
in all three groups, basal metabolite levels were elevated. As
shown in FIG. 5, the major metabolites 3,4-Dihydroxy-Phenylacetic
Acid (DOPAC) and Homovanillic Acid (HVA) were increased by about
40% (DOPAC) and 20-40% (HVA), depending upon the dose.
Example 4: Dopaminergic Activity of ADNS Peptides in Cell Cultures
of Rat Midbrain Dopamine Neurons
[0074] To further characterize the bioactivity of the peptides,
blinded samples were sent to Dr. Michael Zigmond at the University
of Pittsburgh for testing in cultures of newborn rat midbrain
dopamine neurons. Peptide mixture samples (GER9263, GER9264, and
GDR9265 combined in a 1:1:1 ratio) were compared to citrate buffer
alone, two different lots of GDNF, and Neurturin (FIG. 6). Both
lots of GDNF and the 100 ng/ml ADNS peptide mixture exerted about
the same effects in dopamine neuron survival, increasing survival
by about 25-30% over vehicle levels. The peptide mixture at a
concentration of 50 ng/ml promoted an increase in survival of
around 10%, approximately the same effect as 100 ng/ml Neurturin, a
trophic factor that is closely related to GDNF.
Example 5: ADNS Peptides and Response to CNS Delivery in an Aged
Rhesus Monkey
[0075] A study was performed demonstrating that a mixture of three
ADNS peptides (GER9263, GER9264, and GDR9265 combined in a 1:1:1
ratio) exerts pharmacological effects on CNS nigral dopamine
neurons in an aged rhesus monkey similar to those produced by GDNF.
Marked increases of 68-125% in stimulus-evoked dopamine release
were measured in the putamen by in vivo microdialysis. Motor speed,
as measured in fine motor hand movements, increased by up to 58%,
into the range of young adult monkeys. General body movements
increase by 38%, indicating much higher activity levels. The
effects from unilateral treatment were long-lasting (for at least
one month) and bilateral, similar to those resulting from GDNF
treatment. Histopathological analysis of the injection sites in the
substantia nigra revealed only mild, circumscribed pathology from
the peptide injections. The pharmacological effects of ADNS
peptides on upregulating nigrostriatal dopamine system functions
are extraordinary and suggest their potential therapeutic use for
the treatment of Parkinson's disease and age-associated movement
dysfunctions.
[0076] The ADNS peptides tested in this Example are three amidated
peptides predicted to exert potent biological effects similar to
those of Glial Cell Line-Derived Neurotrophic Factor (GDNF). The
effects of GDNF on CNS dopamine neurons fall generally into three
categories: pharmacological upregulation of dopaminergic activity,
neuronal regeneration and neuroprotection. This study was designed
to assess the pharmacological effects of ADNS peptides on
substantia nigra dopamine neurons in the nonhuman primate brain. It
was previously shown that CNS delivery of GDNF increases
stimulus-evoked dopamine release in aged rhesus monkeys (Grondin et
al., 2003). In addition, behavioral correlates of increased
dopaminergic activity were recorded in these animals, improved
motor functions and increased motor speed. The present study was a
case report on one aged monkey that received a 100 .mu.g injection
of ADNS peptides into the substantia nigra of the brain and was
followed for 30 days. Motor speed was measured weekly using an
automated movement analysis panel (MAP) and EthoVision, a video
tracking program. Movement features were rated weekly using a
nonhuman primate clinical rating scale (Zhang, Z. et al., "Motor
slowing and parkinsonian signs in aging rhesus monkeys mirror human
aging.", J Gerontology: Biol. Sci. 55A:B473-B480, (2000)).
Stimulus-evoked dopamine release was analyzed by microdialysis at
the 30 day time point. The animal was then euthanized and the brain
recovered for histopathological analysis.
[0077] Methods Used for Studying ADNS Peptides
[0078] Animal:
[0079] A thirty-four year old female rhesus monkey (1D# NJ05)
weighing 7 kg was used. The animal was diagnosed as having an
inoperable mammary tumor, with the attending veterinarian
suggesting that the monkey be placed in a terminal study and
euthanized for humanitarian reasons. The animal was maintained on a
12-hour light/12-hour dark cycle and housed individually in a cage
measuring 9 square feet, with an elevated perch, front access doors
and side rear access doors connecting the housing cage to an
adjacent activity module. The diet consisted of certified primate
biscuits given in the morning (7:30 AM), and supplemented daily in
the afternoon (1:30 PM) with fresh fruit or vegetables. Water was
available ad libitum.
[0080] All procedures were conducted in the Laboratory Animal
Facilities of the University of Kentucky, which are fully
accredited by the Association for Assessment and Accreditation of
Laboratory Animal Care. Veterinarians skilled in the health care
and maintenance of nonhuman primates supervised all animal
care.
[0081] MRI Imaging:
[0082] Magnetic resonance images (MM) were obtained on a I 0.5T
clinical imager (Siemens Magnetom Vision) using a standard cross
polarized extremity coil. After being sedated with ketamine
hydrochloride (.about.20 mg/kg; i.m.) plus atropine sulfate
(.about.0.04 mg/kg; i.m.), the animal was anesthetized with sodium
pentobarbital (.about.10 mg/kg; i.v.) and imaged to provide
stereotaxic coordinates for peptide delivery. The animal's head was
positioned in the extremity coil using an MRI compatible
stereotaxic head frame. This frame kept the animal's head level and
immobilized at the center of the radio frequency coil using ear and
mouth bars. An initial set of coordinates was taken using the
earbars, toothbar and a zeroing bar targeted to the gum line
between the two upper middle incisors to allow replication any time
the animal was replaced in the stereotaxic apparatus.
[0083] The coil/frame assembly was then positioned to place the
animal's head at magnet isocenter. Sets of T1-weighted 3D-FLASH
images were collected for determination of the brain coordinates
(TR/TE=22/9 ms; FA=35.degree.; FOV=96.times.96.times.90 mm;
Matrix=128.times.128.times.90; Nacq=2; TA=6 min 48 sec). All images
were acquired as coronal slices relative to the brain.
Antero-posterior, lateral and vertical coordinates for stereotaxic
surgery were derived from the T1-weighted coronal brain images. The
interaural line was identified on the scans by modified earbars
containing Vitamin E. This provided a precise reference-point,
which allowed for anteroposterior measurements to the target.
Lateral measurements were determined by measuring the distance from
the sagittal sinus/third ventricle to the target site. Vertical
measurements were determined from the surface of the brain to the
target at the lateral coordinate.
[0084] Surgery:
[0085] Following sedation with ketamine hydrochloride (.about.20
mg/kg; i.m.) plus atropine sulfate (.about.0.04 mg/kg; i.m.), the
animal was intubated via the orotracheal method and intravenous
lines secured. Then, the animal was anesthetized with isoflurane
(1-3%) and placed in an MRI compatible Kopf stereotaxic apparatus
in a ventral-lateral position as per the coordinates previously
(see Anatomical MRI above). The animal was maintained on a heated
blanket and had cardiac and respiratory parameters monitored during
the procedure, which was carried out using sterile field
conditions. Coordinates for peptide injections were determined by
MRI prior to the surgery as described above. After being shaved,
the scalp area was cleaned using antiseptic procedures with sterile
4.times.4 sponges soaked in Betadine.RTM. surgical scrub followed
by 70% isopropyl alcohol. This procedure was repeated. After the
alcohol dried, Betadine.RTM. prep was applied and the animal was
covered with sterile drapes. Then, an incision was made through the
scalp and the skin and muscles overlying the skull were reflected.
Small holes were drilled in the skull directly over the target
area. The overlying meninges were removed to expose the surface of
the brain.
[0086] A 1.0 mg/ml concentration of the three-peptide mixture in
citrate buffer was used. It was sterilized by filtration prior to
injection Using MRI-guided procedures, a 27G needle coupled to a
Hamilton syringe containing 100 .mu.l (i.e. 100 .mu.g) of the
peptide mixture was lowered in the right rostral SNc (AP: 11, L: 5,
DV: 30 from surface of the brain). A volume of 50 .mu.l was
delivered using a nanopump at a rate of 1 .mu.l/min. This was
followed by a 20 min waiting period before retracting the needle
out of the brain (1 mm/min). The needle/syringe assembly was then
moved 1 mm caudally and 0.5 mm laterally and lowered into the more
caudal SNc (AP: 10, L: 5.5, DV: 29 from surface of the brain). This
was followed by a 20 min waiting period before retracting the
needle out of the brain (1 mm/min). After completion of the
injections, the scalp incision was sutured over the exposed areas
per normal procedures and the animal was given an analgesic
(buprenorphine, 0.01 mg/kg, i.m.). Vital signs were monitored until
the animal awakened, at which point the animal was covered with
warm blankets and taken back to its cage and monitored until it was
ambulatory.
[0087] Behavioral Tests:
[0088] To assess changes in motor functions, the animal was
videotaped prior to injecting the peptide mixture, and weekly after
the injection for four weeks. The videotaping cage measured 28
inW.times.32 inH.times.32 inD, had a white background wall and a
clear Lexan window permitting videotaping. The videotaping cage was
illuminated by two 48 in-long fluorescent lights located 30 in
above. Water (via a cage attached bottle) was available ad libitum
throughout the session. The animal was fed fruit or vegetables
after completion of data acquisition and upon return to its home
cage.
[0089] Beginning at 1 PM, a technician entered the room and placed
small food items (e.g. gummy bears) on the ledge of the cage to
elicit the animal to stand-up and reach out for the food. Then, the
animal was videotaped for 30 minutes with no one in the room.
Following this 30-minute videotaping period, the technician
re-entered the room, stopped recording and attached a non-wired
version of the monkey Movement Analysis Panel (MAP, see below) to
the doorway of the cage for a hand retrieval test. Five to six
preferred small food items (e.g. miniature marshmallows) were
placed on each side of the panel. The animals was given 10 minutes
(default time) to retrieve the food items, at which point the
tester re-entered the room and stopped recording. This portion of
the session was videotaped, with a focus on the hands. Starting at
2 PM, the same procedures described above were repeated. At the end
of the testing session, the animal was returned to its home
cage.
[0090] As described above, standardized videotaping procedures were
conducted pre- and post-treatment. Behavioral parameters associated
with motor function were scored from coded videotapes from 0
(normal) to 3 (severe disability) in the following categories:
rigidity, bradykinesia, posture, balance, tremor, and hand
dexterity (see Zhang et al., 2000). Rigidity is defined as a
decrease in limb extension and/or use. Motor dysfunctions were
rated in half-point increments by an experienced rater.
[0091] Distance traveled (cm) was quantified from 8-mm videotapes
(SONY P6-120MPL) using a commercially available video tracking
system EthoVision Pro (version 2.3, Noldus Information Technology,
Asheville, N.C.) coupled to a SONY Digital 8 video cassette
recorder. This system runs on a Pentium based computer with a frame
grabber card (PICOLO, Belgium), so that the analog video signal
coming from the video cassette recorder is digitized and
transferred to the computer. A window on the computer screen
directly displays the video image, and the boundaries within which
tracking took place were defined by accurately tracing the outline
of the cage in the video image, in addition, two zones were
outlined, so that the overall activity measured in the entire cage
could be analyzed in terms of vertical (top half) or horizontal
(bottom half) activity. As described above, the animal was
videotaped for 60-minute periods, pre- and post-treatment, and the
video tracks were analyzed at a rate of 6-sample/sec. For every
sample, the cage was scanned and the position of the tracked animal
was determined by using a gray scale detection method (brightness).
This entails calibrating the software to distinguish the
dark-colored animal from the background, which is then defined as
all other pixels. The back wall of the cage was painted white to
provide a background with a maximum degree of contrast with the
dark-colored primate. This automated method relies on determining
the position of the center of mass of the animal in the cage, and
the resultant x-y coordinates extracted as a function of time are
used for calculating the movement pattern during the observation
period. These coordinates were subsequently related to actual
spatial measures by calibrating the software to the dimension
(width) of the cage, the distance traveled by the animal were
calculated in centimeters instead of pixels.
[0092] Movement Analysis Panel (MAP):
[0093] In addition, fine/hand motor movement times in retrieving
food items from a platform level placed in a receptacle chamber
were measured using an automated clear Lexan MAP attached to the
door opening of the home cage (see Gash, D. M. et al. "An automated
movement analysis panel for upper limb motor functions in rhesus
monkeys and humans", J. Neurosci Methods 89:111-117, (1999) and
Zhang et al., 2000). The receptacle chamber is divided into left
and right halves, and is accessible on each side through two
portals (armhole portal and receptacle portal). Movement times were
measured by arrays of three photodiodes around each portal that
automatically relayed to the computer when one or more beams were
broken by passage of the monkey's arm/hand. Testing was conducted
in the afternoon, prior to injecting the peptide mixture, and
weekly thereafter for four weeks. Fresh fruit and vegetables were
given to the animal after completion of the testing session. A
day's testing session consisted of twelve trials, six on each side
alternating between the right and left hand.
[0094] Microdialysis Studies:
[0095] The animal underwent bilateral putamenal microdialysis one
month post ADNS peptide injection. Using the method described
below, in vivo microdialysis procedures had also been conducted
previously in the right striatum of the same animal (date: 2/10/04;
coordinates: AP:20.5 mm, L:10.2 mm, DV from cortex:21 mm).
[0096] Following normal MRI-guided stereotactic procedures (see
Surgical procedures for ADNS peptide injection), custom-made CMA/11
dialysis probes with a membrane length of 3 mm and diameter of 0.24
mm (CMA Microdialysis, North Chelmsford, Mass.) were positioned (1
mm/min) bilaterally in the putamen (AP:20 mm, L:10.5 mm, DV from
cortex:20 mm). Probes were perfused continuously at a rate of 1.2
.mu.l/min with artificial cerebrospinal fluid using a computerized
multisyringe pump (World Precision Instruments). Microdialysate
fractions were collected at 30 min intervals.
[0097] Following a 1-hour application of artificial cerebrospinal
fluid to collect baseline fractions, excess potassium (100 mM KCl,
47.7 mM NaCl) was then included in the perfusate for a single
30-min fraction (t0-t30). Two hours later 250 amphetamine was
included in the perfusate for a single 30-min fraction (t1-t150).
Three additional fractions were collected after discontinuing
amphetamine administration (t180-t240). The incision was then
closed as per normal surgical procedures. Microdialysate fractions
were analyzed using standard high performance liquid chromatography
procedures coupled with electrochemical detection.
[0098] Tissue Collection Procedures:
[0099] Tissue biopsies were collected for possible future use. At
the end of the dialysis session, the animal was immediately
euthanized. The deeply anesthetized animal (2 ml pentobarbital,
i.v.) was transcardially perfused with heparinized ice-cold saline
(6 L). Then, the brain was removed quickly, and dropped into a
container of cold saline, which was placed on wet ice and taken
back to the laboratory. Using an ice-cold mold, the brain was
sectioned into 4-mm coronal slabs, rostral of the midbrain.
[0100] Multiple tissue punches were taken bilaterally from frozen
4-mm thick coronal tissue sections using a 14G biopsy needle in the
caudate nucleus (n=18 per side, tissue slabs #3, #4 and #5),
putamen (n=18 per side, tissue slabs #4, #5, #6), nucleus accumbens
(n=7 per side, tissue slabs #3 and #4) and globus pallidus (n=5 per
side, tissue slabs #6). Separate needles were used for the right
and left (green tape) hemisphere. All punches were rapidly
transferred to pre-weighed storage tubes, weighed once more, and
stored at -80.degree. C. Pictures of the punched slabs were taken
to document the punching pattern, and then they were stored at
-80.degree. C.
[0101] The midbrain was taken out as a block, which included the
cerebellum, and post-fixed for quantitative immunocytochemistry of
substanita nigra dopamine neurons and TH+ processes. To do so, the
midbrain was immediately immersed in 4% paraformaldehyde in 0.1 M
phosphate buffer (pH 7,4) at 4.degree. C. for three days and
transferred to 15% sucrose solution until saturated for sectioning.
Then, a series of 40 .mu.m-thick coronal sections were cut on a
frozen sliding microtome. One out of every 12th adjacent sections
was processed for cresyl violet (Nissl) and hemotoxylin and eosin
(H & E) staining. Also, 1/12th adjacent sections were processed
for the following staining: a) 1:1000 mouse anti-glia fibrillary
acidic protein (GFAP) antibody for astrocytes, b) 1:200 mouse
anti-HLA-DR antibody for reactive microglia, and c) 1:1000 mouse
anti-tyrosine hydroxylase (TH) antibody for dopaminergic neurons
(see Ai et al., 2003).
[0102] Effects of ADNS Peptides on an Aged Rhesus Money
[0103] The animal recovered without problems from peptide delivery
into the right substantia nigra. No clinically observable abnormal
behaviors (e.g. auto-mutilation, stereotypic movements, dyskinesia,
vomiting) were noted throughout the 30-day study.
[0104] As described above, standardized videotaping procedures were
conducted pre- and post-treatment to assess changes in motor
functions from coded videotapes. Prior to injecting the
three-peptide mixture into the right substantia nigra, the animal
was given a cumulative score of 3.25 points on the rating scale
(See Table 2). Although the effect was variable, this score
improved (the lower the score, the better the movement functions)
by over 30% (i.e. 1 point) by the fourth week of the study.
Similarly, distance traveled (cm) measured over weekly 60-minute
periods using the automated video-tracking system (EthoVision)
improved up to 38% by the fourth week post treatment versus
baseline locomotor activity (from 7064 cm to 9780 cm). Last but not
least, MAP performance times for left hand motor were 56% faster by
week four post peptide treatment (from 0.81 sec to 0.36 sec). Right
hand performance times were already faster than the left
pre-peptide treatment. They further improved in the 4 weeks
post-treatment, with performance times 14% faster (from 0.36 sec to
0.31 sec).
[0105] In vivo microdialysis was used to investigate the dynamics
of dopamine release in the basal ganglia. Measurements were carried
out in the right putamen four weeks post peptide treatment (see
FIGS. 7A and B). In particular, FIG. 7 shows the results of
potassium (K+) and d-amphetamine (d-AMPH) evoked release of
dopamine measured in the right putamen of NJ05 using microdialysis
to collect samples for neurochemical analysis. FIG. 7A shows the
first recordings made Feb. 10, 2004, several years prior to the
ADNS peptide study. In aging monkeys, dopamine evoked release of
dopamine to K+ and d-AMPH normally decreases with increasing age.
FIG. 7B shows the second set of recordings made thirty days after
ADNS peptide injections into the right substantia nigra on Apr. 27,
2006. K+ evoked release was increased from the 2004 reading from
36.5 nM to 82 nM. D-AMPH evoked release of dopamine increased from
74 nM to 125 nM after ADNS peptide administration. Thus, in
comparison to measurements recorded under similar conditions two
years earlier in the same animal, potassium-evoked overflow of
dopamine was increased by 125% at 30 days post ADNS peptide
administration (from 36.5 nM to 82 nM). Similarly,
amphetamine-induced overflow of dopamine was increased by 68%
compared to measurements recorded two years earlier (from 74 nM to
125 nM).
[0106] Basal levels of dopamine and dopamine metabolites in the
striatum were determined from measurements in the microdialysates
prior to potassium and amphetamine stimulation. Basal dialysate
levels of dopamine and HVA showed small changes from the baseline
levels two years earlier (Table 2). However, basal levels of
extracellular DOPAC were increased by 230% at thirty days post
peptide injection compared to the earlier baseline measures (Table
3).
[0107] The histopathological response to the injection of peptides
in the nigral region was mild (see FIGS. 8 and 9). In FIG. 8, one
of the injection sites (arrow) is shown using standard
histochemical techniques for Nissl staining and hematoxylin and
eosin (H & E) staining. Immunostaining was conducted to assess
the response of astrocytes (GFAP positive cells) and microglia
(HLA-DR positive cells) to the injections. In FIGS. 8A and B, this
injection site (arrow) was just dorsal to the substantia nigra,
pars compacta (SNc). While there is an evident response at the
injection site and a smaller satellite area (*) of reactivity
dorsal to the main area, the injury response is very circumscribed.
FIG. 8C shows that reactive astrocytosis, as assessed by GFAP
positive reactivity around the needle track, is minimal,
approximately that expected from a needle tract injury alone. In
FIGS. 8D and E, the injury response appears similar using H & E
to that seen with Nissl. The injury response is localized and does
not seem to involve adjacent cells. Reactive microglia (HLA-DR+
cells) are a prominent constituent of the injury response (arrow
and *, FIG. 8F). (In FIG. 8, Cerebral peduncle=CP; Substantia nigra
reticulatia=SNr; Ventral Tegmental Area=VTA. Scale bars are
included in each photomicrograph.) The injection site showed
reactive cells in an area about 200 .mu.m wide by 400 .mu.m long in
Nissl-stained and H & E-stained sections (FIGS. 8A, B, D and
E). The response consisted of activated microglia (HLA-DR positive
cells, FIG. 8F). The absence of pronounced GFAP immunostaining
(FIG. 8) indicated that the injection did not stimulate a glial
reaction.
[0108] The substantia nigra pars compacta (SNc) containing the
population of dopamine neurons that degenerates in Parkinson's
disease is evaluated in the series of photomicrographs set forth in
FIG. 9. In FIG. 9A, Nissl-rich neurons (arrowheads) adjacent to the
peptide injection site (*) appear normal with prominent nuclei
evident in the nucleus of some cells. Nissl staining corresponds to
the presence of rough endoplasmic reticulum in the cytoplasm and
indicates cells actively synthesizing protein. The H & E
stained section in FIG. 9B also shows neurons with normal features
(arrowheads) adjacent to the injection site (*). FIG. 9C shows that
there are only a few scattered activated microglia (arrowheads
showing HLA-DR positive cells) in the SNc. Large numbers would
indicate ongoing pathological processes. Tyrosine hydroxylase (TH)
is the rate-limiting enzyme in dopamine synthesis. The TH positive
cells shown in FIG. 9D are dopamine neurons. Their size and
exuberant expression of TH positive processes are indicative of
healthy, active cells. Scale bars are included in each
photomicrograph. Dopamine neurons in the substantia nigra appeared
to be normal (FIG. 9). Tyrosine hydroxylase immunostaining (FIG.
9D) revealed large dopamine neuron perikarya (cell bodies) with
extensive neuritic processes. Along with the Nissl and H & E
stained sections (FIGS. 9A and B), the nigral cells showed features
characteristic of healthy neurons. A few activated microglia
(HLA-DR positive cells, FIG. 9C) were present in the nigral region,
a typical feature of this brain region in healthy aged monkeys.
Large numbers of activated microglia would be indicative of an
ongoing disease process.
[0109] The subject in this study was a very old rhesus monkey, 34
years old. One year for a rhesus monkey is roughly equivalent to
three years of human life, making this animal equivalent to a 100
year old person. The monkey was used in this study because it had a
terminal disease, mammary cancer. The closest comparable monkeys in
an earlier study treated with GDNF were 22-24 years old (Grondin et
al., 2003). They received infusions of GDNF into the brain for 24
weeks while NJO5 had a single injection of an ADNS peptide mixture
and was monitored for one month. Despite the differences, many of
the responses were comparable to those seen to GDNF. NJO5 motor
performance times on the MAP improved within four weeks on both the
right (14%) and left (56%) sides. The improved motor speeds
approached the speeds of aged monkeys receiving GDNF and those of
normal young adult animals. Consistent with increased motor speed,
general locomotor activity was increased by 38% by four weeks of
treatment in NJO5. There were neurochemical changes in NJO5's brain
along with the behavioral improvements. Both potassium- and
amphetamine-evoked release were increased (125% and 68%,
respectively) in the putamen in comparison to pretreatment levels.
This was similar to the increased evoked release of dopamine in
response to the same stimulants in aged rhesus monkeys treated with
GDNF (Grondin et aI., 2003). Basal dialysate levels of dopamine,
HVA and DOPAC showed high variability, but were not significantly
changed in aged GDNF recipients. NJO5's basal dopamine and dopamine
metabolite levels were in the same range as the GDNF and
vehicle-treated old animals. The only dramatic change seen in this
animal was in DOPAC levels, which increased over three-fold post
ADNS peptide treatment. The significance of this response is that
it reflects higher levels of dopamine metabolism in the
striatum.
[0110] Histopathology was much less extensive than the damage in
the same region from the infusion of GDNF (see Gash, D. M. et al.,
"Trophic factor distribution predicts functional recovery in
parkinsonian monkeys", Ann Neurol 58(2):224-33 (2005)). The
dopamine neurons in the substantia nigra appeared healthy, with
numerous neuritic processes.
TABLE-US-00002 TABLE 2 Changes in motor functions post ADNS
peptides delivery into the right substantia nigra. The reduction in
the disability score means that the motor functions such as walking
and balance were improving. The locomotor activity level increases
by week four also reflect that the animal was increasing the time
and distance in walking. The Movement Analysis Panel (MAP) scores
demonstrate much faster hand fine motor movements by week 4 after
treatment. Locomotor Left Map Right MAP Disability Activity Times
times Score (pts)/% (cm)/% (sec)/% (sec)/% Treatment baseline
baseline baseline baseline Baseline 3.25 7064 0.81 0.36 Week 1
2.00/-38% 8422/+19% 0.86/+6% 0.45/+25% Week 2 2.00/-38% 7136/+1%
1.09/+35% 0.39/+8% Week 3 2.50/-23% 6368/-10% 0.75/-7% 0.34/-6%
Week 4 2.25/-31% 9780/+38% 0.36/-56% 0.31/-14%
TABLE-US-00003 TABLE 3 Changes in basal dialysate levels of
dopamine and dopamine metabolites in the right putamen, 30 days
post ADNS peptide delivery into the right substantia nigra. The
large increase in levels of the dopamine metabolite DOPAC indicate
increase dopaminergic activity. As the enzyme (monoamine oxidase B)
for metabolizing dopamine to DOPAC is on the outer membrane of
mitochondria, it also reflects either more active mitochondria and
increased numbers of mitochondria. Hemisphere Dopamine (nM) HVA
(nM) DOPAC (nM) Pre-peptides 5.6 5033 127 Post-peptides 4.9 4191
419
Example 6: Materials and Methods
[0111] The following materials and methods were used in the
following examples.
[0112] Materials:
[0113] Unless otherwise stated, all cell reagents and assays were
purchased from Invitrogen. All other materials and chemicals are
reagent grade.
[0114] DNSP-17 (GER 9263), DNSP-5 (GER 9264), DNSP-11 (GER 9265),
and Biotinylated DNSP-11: DNSP-17 (sequence:
ERNRQAAAANPENSRGK-amide (SEQ ID NO: 2)), DNSP-5 (sequence:
FPLPA-amide (SEQ ID NO: 3)): DNSP-11 (sequence: PPEAPAEDRSL-amide
(SEQ ID NO: 4)) and biotinylated DNSP-11 (bDNSP-11; sequence:
biotin-PPEAPAEDRSL-amide (SEQ ID NO: 4)) were synthesized and
RP-HPLC purified to >98% by AC Scientific (Duluth, Ga.) and the
W. M. Keck Foundation Biotechnology Resource Laboratory at Yale
University. Peptides were characterized for purity and correct
sequence by MALDI-TOF LC-MS and Edman degradation. DNSP-11 was
determined to be stable, in vitro, at a variety of experimentally
relevant concentrations and temperatures, including 37.degree. C.
in sterile pH 5 citrate buffer for 31 days.
[0115] Tissue Preparation for DNSP-11 Staining in Substantia Nigra
at Postnatal Day (PN10):
[0116] Tissue was prepared from SD pups. Brains were rinsed in
Dulbecco's Phosphate Buffered Saline (DPBS, Gibco), and submerged
in 4% paraformaldehyde pH 7.4 for 48 hours. Following submersion in
30% sucrose, brains were sectioned coronally (40 .mu.m) and stored
in cryoprotectant solution at -70.degree. C. until processed for
immunohistochemistry.
[0117] DNSP-11 Treatment of Mesencephalic Cells:
[0118] Timed pregnant SD rats (Harlan) were used to obtain the
ventral mesencephalon from E14 fetuses. The dissected tissue was
collected in cold Neurobasal.TM. medium and rinsed twice with cold
Dulbecco's PBS. The cells were chemically (TrypLE.RTM.) and
mechanically dissociated to yield a single cell suspension. The
solution was centrifuged at 169 g for 6 minutes and the pellet was
resuspended in Dulbecco's Modified Eagle Medium (DMEM). Cells were
plated in a 25 .mu.L micro-island at a density of 4000 cells/.mu.L
on poly-D-lysine coated 24-well plates (Sigma). Following
adherence, cells were supplemented with warm Neurobasal.TM. media
containing 2 mM glutamine, 1.times.N.sub.2, and 100 units of
penicillin/streptomycin. Neurotrophic compounds were added at each
media addition, including initial plating and DIV 2. A dose
response of the peptides (0.03 ng to 10 ng/mL) was added to a
24-well plate following media supplementation.
[0119] MN9D Cell Cultures:
[0120] The MN9D cell line has been described by Choi (1991) Brain
Res. 552:67-76 and was a gift from Michael Zigmond. Cells were
cultured in DMEM supplemented with 10% Fetal Bovine Serum (FBS,
Hyclone), 50 U/mL penicillin and streptomycin. For experiments, the
cells were plated on 24-well poly-D-lysine in DMEM with 1% (v/v)
penicillin-streptomycin. The cells were grown at 37.degree. C. in
5% CO.sub.2.
[0121] Caspase-3 Activity Assay in MN9D Cells:
[0122] MN9D cells were plated to 100,000 cells/well. Cell cultures
were exposed to DNSP-11 (1 ng/mL) or buffer for 1 hour prior to 15
min 100 .mu.M 6-OHDA exposure. Caspase-3 activity was monitored
after 3 hours by fluorescence (excitation/emission 496/520 nm)
using the Enz Chek Caspase-3 kit. Protein levels of lysed cells
were measured by BCA assay (BioRad) and normalized for every
experiment. Data expressed as % control and repeated a minimum of 3
times.
[0123] Terminal dUTP Nick-End Labeling (TUNEL) Assay in MN9D
Cells:
[0124] After treatment with DNSP-11, MN9D cells were fixed and
labelled to assess degenerative nuclear changes as indicated by the
extent of high-molecular weight DNA strand breaks. DNA
fragmentation was detected by using steptavidin-horseradish
peroxidise conjugate followed by the substrate diaminobenzidine
(DAB) generating a colored precipitate. Ratios between apoptotic
and total cells were determined (4 random fields/well; 4
wells/group). Experiments were repeated 3 times.
[0125] Double Fluorescent Immunostaining of DNSP-11:
[0126] Floating sections were pretreated with 0.2% H.sub.2O.sub.2
in potassium phosphate buffered saline (KPBS) for 10 minutes and
blocked with 4% normal goat serum in KPBS for 1 hour. Then,
sections were incubated overnight with both rabbit anti-hDNSP-11
antibody (1:2000, Alpha Diagnostic) and mouse anti-TH antibody
(1:1000, Chemicon) in KPBS at 4.degree. C. After washing with KPBS,
the sections were incubated with Alexa-488 conjugated goat
anti-rabbit IgG (1:500, Molecular Probes) and Alexa-568 conjugated
goat anti-mouse IgG (1:500, Molecular Probes) for 3 hours. The
sections were washed extensively and visualized with a Nikon
fluorescence microscope.
[0127] Animals and Surgical Procedures for Normal and
6-OHDA-Lesioned Rats:
[0128] Fischer 344 (F344) rats were used for all experiments and
maintained under a 12 hour light/dark cycle with food and water
provided ad libitum. All procedures were approved by the University
of Kentucky Institutional Animal Care and Use Committee following
AAALACI guidelines.
[0129] Infusion Delivery of DNSP-11 or Vehicle:
[0130] Isoflurane anesthetized (1.5-2.5%) F344 rats received 5
.mu.l of 6 .mu.g/.mu.L DNSP-11 solution or citrate buffer vehicle
solution in a blinded manner. Treatment was delivered to the nigral
cell bodies using the same stereotaxic coordinates and protocol for
solution delivery as in studies of GDNF.sup.13.
[0131] Reverse Microdialysis:
[0132] Reverse in vivo microdialysis was accomplished using methods
and brain coordinates described by Hebert et al. (1996) J.
Pharmacol. Exper. Ther. 279:1181-1190. CMA 11 microdialysis probes
with a 4.0 mm membrane length and 6 kDa molecular weight cut-off
were placed within the rat striatum.
[0133] Unilateral 6-OHDA Lesions:
[0134] The 6-OHDA solution was delivered to two injection sites
along the medial forebrain bundle (MFB) using a protocol described
by Lundblad et al. (2002) Eur. J. Neurosci. 15:120-132. Five weeks
after the unilateral 6-OHDA MFB lesion procedure, animals were
grouped based on apomorphine (0.05 mg/kg, s.c.)-induced rotational
behaviour: Animals with >300 rotations per 60 minutes were
selected. Lesioned animals received 5 .mu.L of either a 20
.mu.g/.mu.L DNSP-11 solution or citrate buffer vehicle solution in
a manner similar to infusion delivery in normal animals.
[0135] Neurochemical Content of Tissue:
[0136] Lesioned animals were euthanized 5 weeks after DNSP-11 or
vehicle infusion. The brains were sliced into 1 mm thick sections.
Tissue punches were taken from the striatum and the substantia
nigra and they were weighed, quick frozen and stored at -70.degree.
C. until they were assayed by high performance liquid
chromatography with electrochemical detection as described by Hall
et al. (1989) LC/GC-Mag Sep Sci 7:258-265.
[0137] Apomorphine-Induced Rotational Behavior Testing:
[0138] Lesion severity was assessed prior to DNSP-11 treatment
using apomorphine (0.05 mg/kg, s.c.)-induced rotational behavior.
Beginning one week after DNSP-11 treatment, apomorphine-induced
rotational behavior was monitored weekly for four weeks as
described by Hoffer et al. (1994) Neurosci Lett. 182:107-111 (1994)
and Hudson et al. (1993) Brain Res. 626:167-174 (1993).
[0139] DNSP-11 Pull-Down Analysis:
[0140] The F344 substantia nigra was homogenized in homogenization
buffer (modified from York et al. (2005) FASED J. 19: 1202-4 with
20 mM HEPES, pH 7.4) and cytosolic fraction (supernatant) collected
after 30 minutes at 100,000 g. 50 .mu.g of bDNSP-11 was incubated
with fraction for 15 minutes on ice. Sample was added to
streptavidin magnetic beads (New England Biolabs), pelleted, and
washed four times in homogenization buffer. Bound proteins were
eluted by Solubilization/Rehydration Solution (7M Urea, 2M
Thiourea, 50 mM DTT, 4% CHAPS, 1% NP-40, 0.2% Carrier ampholytes,
0.0002% Bromophenol blue), and analyzed by 2D-PAGE and MALDI-TOF
MS.
Example 7: Neurobiological Actions of DNSP-11
[0141] GDNF is endogenously produced as a pre-proprotein of 211
amino acids that is processed and secreted as a mature homodimer
with a molecular weight of 32-42 kDa. The following examples
illustrate the neurobiological actions of dopamine neuron
stimulating peptide-11 (DNSP-11), an 11-mer peptide that has been
independently predicted to be an endopeptidase cleavage product
from the human GDNF prosequence (FIG. 10A).
[0142] FIGS. 10A and 10B illustrate the sequence origin and
homology of DNSP-11. DNSP-11 (filled) is an 11 amino acid sequence
present in the proprotein region of the 211 amino acid human
preproGDNF sequence. After cleavage of the pre-signal sequence
(shaded), DNSP-11 is predicted to be cleaved from the proprotein at
flanking dibasic cleavage sites by endopeptidases. Further
predicted processing yields the C-terminal amidated peptide. The
N-terminal (striped) and C-terminal (checkered) proprotein
fragments and mature GDNF (open) protein are shown. The sequence
figure is not drawn to scale to highlight the processing of
DNSP-11. DNSP-11 (FIG. 10B) shows high sequence homology to the rat
and mouse proGDNF sequences suggesting a conserved function.
[0143] In vivo expression of the DNSP-11 sequence in the substanta
nigra of the ventral mesencephalon from SD pups at postnatal day 10
(PN10) was examined. Immunostaining for DNSP-11 in the
mesencephalon of the SD pups indicated that the sequence is present
endogenously in tyrosine hydroxylase positive (TH+) dopaminergic
neurons of the substantia nigra at PN10 ns (yellow). The DNSP-11
sequence colocalized within dopaminergic cell bodies at PN10.
[0144] The neurotrophic effects of DNSP-11 were studied by
comparing its effects to the well-known effects of GDNF on the
maintenance of primary mesencephalic cell cultures from E14 SD rat
embryos. E14 SD rat embryo primary dopaminergic neurons from the
ventral mesencephalon were grown for 5 days in vitro and
neurotrophic molecules were added at each media change, including
initial plating and day 2. GDNF (FIG. 11A, open bars) and DNSP-11
(FIG. 11A, solid bars) were added at various concentrations (0.03,
0.1, 1.0 and 10 ng/ml; 10 mM citrate buffer+150 mM NaCl, pH 5) and
were seen to significantly increase TH+ neuron counts (+SD; one-way
ANOVA with Newman-Keuls post hoc analysis, *p<0.05 and
**p<0.01) Specifically, DNSP-11 increased cell survival 75% over
citrate buffer control, as indicated by immunocytochemical staining
of TH+ neurons 5 days in vitro (FIG. 11A). Furthermore, DNSP-11
significantly enhanced morphological changes consistent with a
neurotrophic molecule including: neurite length, total number of
branches, and increased total number of TH+ cells (Table 4; FIG.
11B). These effects were similar to those observed for GDNF in
these cells, including an increase in the size of TH+ neurons,
which was not observed for DNSP-11 (Table 4). Photographs in FIG.
11B of treated E14 primary dopaminergic neurons demonstrate that
both GDNF and DNSP-11 treated cells (0.1 ng/ml) displayed enhanced
cell survival, neurite length, and total number of branches.
[0145] In Table 1, cell survival and morphological parameters were
quantified for control (citrate buffer) and experimental (0.1 ng/ml
GDNF or 0.1 ng/ml DNSP-11) conditions. For morphology, five fields
per well (minimum of 15 cells/field; 3-4 independent experiments)
were photographed at 20.times. magnification and quantified using a
Bioquant Image Analysis System. DNSP-11 increased cell survival and
morphological parameters comparable to GDNF, including combined
neurite length and total branches. Soma size was not increased by
the addition of DNSP-11. A one-way ANOVA was used to test for
significance among groups, followed by a Newman-Keuls post hoc
analysis. Significance between control and experimental conditions
was determined at *p<0.05 and **p<0.01.
TABLE-US-00004 TABLE 4 GDNF DNSP-11 Control 0.1 ng/ml Control 0.1
ng/ml Cell survival 100 .+-. 15 *158 .+-. 12 100 .+-. 16 *161 .+-.
17 n = 8 n = 8 n = 7 n = 7 Combined neurite 242 .+-. 12 **310 .+-.
16 222 .+-. 11 **306 .+-. 23 length (um) n = 135 n = 106 n = 139 n
= 59 Soma size (um.sup.2) 171 .+-. 4 177 .+-. 4 168 .+-. 3 165 .+-.
5 n = 135 n = 106 n = 139 n = 59 Average branches 3.8 .+-. 0.2
**4.7 .+-. 0.2 3.1 .+-. 0.2 **4.4 .+-. 0.3 per neuron n = 135 n =
106 n = 139 n = 59
[0146] To evaluate DNSP-11's neuroprotective properties, DNSP-11
was compared to GDNF in its protection against 6-OHDA-induced
toxicity in the dopaminergic cell line, MN9D. MN9D dopaminergic
cells were incubated for 1 hour with either citrate buffer
(control), 1 ng/mL of DNSP-11 or GDNF prior to 100 .mu.M 6-OHDA
exposure for 15 min. Data are +SD, one-way ANOVA with Tukey's post
hoc analysis, *p<0.05, **p<0.01, ***p<0.001 vs. control;
#p<0.05, ##p<0.01, ###p<0.001 vs. 6-OHDA. As seen in FIGS.
11C and D, 100 .mu.M 6-OHDA significantly increased TUNEL staining
and caspase-3 activity in MN9D cells (FIGS. 11C and D).
Pretreatment with DNSP-11 or GDNF produced a significant reduction
in the percent of TUNEL positive cells and caspase-3 activity
(FIGS. 11C and D). Thus both DNSP-11 and GDNF protect against
6-OHDA toxicity as demonstrated by reductions in TUNEL staining at
24 h (FIG. 11C) and caspase-3 (FIG. 11D) activity at 3 h after
6-OHDA exposure.
Example 8: Uptake of DNSP-11 into Neurons
[0147] Additional studies were carried out to determine if DNSP-11
is actively taken up into dopamine-containing neurons in vivo. A
single administration of 30 .mu.g of DNSP-11 was delivered into the
rat substantia nigra. Animals were euthanized at 0.5, 1.5, 4, 24
and 48 hrs after injection to visualize distribution of DNSP-11
using antibodies raised against DNSP-11 and the ubiquitinated form
of DNSP-11. DNSP-11 antibodies labelled the cytosol and neurites of
neurons in the area of the substantia nigra within 30 minutes after
injection. DNSP-11 was taken up by neurons in both the substantia
nigra, pars reticulata (SNr) and substantia nigra, pars compacta
(SNc). The fluorescent immunostaining for DNSP-11, TH and the
merger of photomicrographs from each showed that TH-positive
dopamine neurons populate the SNc and the ventral tegmental area
(VTA). Higher power micrographs from the SNc. DNSP-11
immunostaining revealed uptake into the perikaryon, nucleus, and
neurites of TH+ cells.
[0148] At 1.5 hrs post-injection, staining for TH+ and DNSP-11
showed overlap in the pars compacta of the substantia nigra and
some labeling in the pars reticulata, supporting potential uptake
of DNSP-11 into GABAergic neurons. Immunohistochemical staining for
DNSP-11 diminished 3 hrs after injection and was absent at 24 hrs
and beyond, indicating that there is a rapid uptake of DNSP-11 into
neurons.
Example 9: Effect of DNSP-11 on Dopamine Neurochemistry
[0149] Prior studies with GDNF have shown robust effects on both
potassium and amphetamine-evoked release 28 days after a single
injection into the rat substantia nigra (Hebert et al. (1997) J.
Pharm. Exp. Thera. 282: 760) indicating the functional effects of
this trophic factor on dopamine signaling in the normal rat
striatum. In the present experiment, 30 .mu.g of DNSP-11 was
injected into the right substantia nigra of normal young male
Fischer 344 rats. Twenty-eight days after injection, in vivo
microdialysis was performed in these animals to investigate
dopamine neurochemistry in the ipsilateral striatum. Resting levels
of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC) and
homovanillic acid (HVA) were significantly increased by over 100%
in the DNSP-11 treated rats as compared to controls (FIG. 12A).
These data indicate longer term effects of DNSP-11 on dopamine
neuron function, and are analogous to prior results involving GDNF
administration in rats and nonhuman primates. Winkler et al. (1996)
J. Neurosci. 16: 7206; Hebert et al. (1996) J Pharmacol Exper Ther.
279: 1181-1190 (1996).
[0150] The in vitro studies and in vivo measures of the effects of
DNSP-11 led to an investigation of the potential neurorestorative
properties of DNSP-11 to damaged dopamine neurons in a unilateral
rat model of PD. Fischer 344 rats received dual-site unilateral
injections of 6-OHDA to produce extensive destruction of the
ascending dopaminergic system that resulted in a greater than 99%
depletion of striatal dopamine content ipsilateral to the site of
the 6-OHDA injections. Rats were tested 3-4 weeks after the
injection of 6-OHDA using low-dose (0.05 mg/kg, i.p.)
apomorphine-induced rotational behavior. In rats that rotated
greater than 300 turns/60 minutes, 30 .mu.g of DNSP-11 was injected
into the ipsilateral substantia nigra. DNSP-11 produced a
significant .about.50% decrease in apomorphine-induced rotational
behavior that was significant 1 week after administration and this
effect was maintained for at least 4 weeks after DNSP-11 (FIG.
12B). At 5 weeks, the substantia nigra and striatum from each rat
was analyzed by high performance liquid chromatography coupled with
electrochemical detection. A single injection of DNSP-11 was found
to significantly increase levels of dopamine and the dopamine
metabolite, DOPAC, by .about.100% in the substantia nigra,
indicating that DNSP-11 has a powerful neurotrophic-like
restorative effect on dopamine neurons in this animal model of late
stage PD (FIG. 12C).
[0151] As shown in FIG. 12A, 28 days after DNSP-11 or citrate
buffer vehicle was delivered to the nigral cell bodies, the DNSP-11
treatment group showed significantly higher basal neurochemical
concentrations of DA, DOPAC and HVA. Basal DA increased from
26.0.+-.2.7 nM in the vehicle treatment group to 45.8.+-.7.7 nM in
the DNSP-11 treatment group (t.sub.(31)=2.255, p=0.0314). Basal
concentrations of DOPAC increased from 3355.+-.338 nM in the
vehicle group to 6544.+-.836 nM in the DNSP-11 group
(t.sub.(31)=3.293, p=0.0025), and HVA, increased from 2419.+-.251
nM with vehicle treatment to 4516.+-.502 nM with DNSP-11 treatment
(t.sub.(30)=3.588, p=0.0012). All data were analyzed using a
two-tailed unpaired t-test *p<0.05. FIG. 12B shows the results
of assessment of apomorphine (0.05 mg/kg) induced rotational
behavior prior to infusion treatment (Pre) and once weekly for 4
weeks after DNSP-11 or vehicle treatment. Drug-induced rotational
behavior is expressed as a percentage of vehicle treatment and
showed a significant decrease in rotational behavior beginning one
week after DNSP-11 treatment that lasted for all 4 weeks post
DNSP-11. The data were analyzed using a one-way ANOVA for repeated
measures (F.sub.(4,39)=4.807, p=0.0005) with Bonferroni's multiple
comparison test *p<0.05, **p<0.01, ***p<0.001. FIG. 12C
shows that DNSP-11 treatment significantly increased levels of DA,
(74%) and DOPAC (132%) in the substantia nigra of unilateral
6-OHDA-lesioned rats. DA content was determined to be 34.7.+-.6.4
ng/g in the vehicle treatment group and 59.1.+-.7.3 ng/g in the
DNSP-11 treatment group (t.sub.(13)=2.521, p=0.0265). DOPAC tissue
content was determined to be 7.10.+-.1.40 ng/g in the vehicle
treatment group and 16.48.+-.4.01 ng/g (t.sub.(13)=2.33, p=0.0364)
in the DNSP-11 treatment group. All data were analyzed using a
two-tailed unpaired t-test, *p<0.05.
Example 10: Interaction of DNSP-11 with Protein Partners
[0152] In order to identify the interactions of DNSP-11 with
protein partners and to gain insight into the cellular mechanisms
involved with the actions of DNSP-11, a pull-down assay was
performed with homogenate from isolated substantia nigra of normal
young Fischer 344 rats. Cytosolic and membrane fractions were
collected and incubated with biotinylated DNSP-11 for 30 minutes.
Bound proteins were pulled down by strepavidin magnetic beads,
extensively washed to remove non-specific binders, eluted with
solubilization/rehydration buffer and separated by 2D-PAGE.
[0153] Specifically, a solution of 25 .mu.L GFR.alpha.1 (1 mg/mL)
was incubated with 50 .mu.L of Dynabeads.RTM. (Invitrogen) in wash
and bind buffer (0.1M sodium phosphate, pH 8.2, 0.01% Tween.RTM.
20) for 10 minutes at room temperature. The beads were then washed
three times in 100 .mu.L of wash and bind buffer. 2 .mu.g of GDNF
was added and incubated for 1 hour at 4.degree. C. 25 .mu.L
GFR.alpha.1 (1 mg/mL) was incubated with 40 .mu.g of biotinylated
DNSP-11 (bDNSP-11) for 1 hour at 4.degree. C. They were then added
to 50 .mu.L of hydrophilic streptavidin magnetic beads (New England
Biolabs) and incubated for an hour at 4.degree. C.
[0154] Several spots were observed in both the cytosolic and
membrane fractions, indicating that DNSP-11 is able to bind
proteins found within the substantia nigra. To identify these
binding partners, protein bands were excised from the gels, trypsin
digested, and analyzed by MALDI-TOF mass spectrometry. From these
preliminary studies, approximately 20 proteins were identified. Of
these, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a protein
with a link to PD and apoptosis, was identified. This result was
confirmed by in vitro pull down assays with pure GAPDH and
DNSP-11.
[0155] In addition, a pull-down assay of DNSP-11 with GFR.alpha.1
indicated that the two molecules do not interact, like mature GDNF
(FIG. 13; F-Flow through, E-Elution). Moreover, the absence of
interaction between GFR.alpha.1 with DNSP-11 is supported by
ELISA.
[0156] A gel filtration study was performed using a 120 mL
Sephacryl S-200 column at a constant 1 mL/min flow rate. Individual
300 .mu.M solutions of GAPDH (.about.150 kDa; FIG. 14, dotted line)
or GDNF (.about.30 kDa; FIG. 14, dashed line) eluted at expected
retention times for their sizes of 50 min (FIG. 14, star) and 64
min (FIG. 14, pound sign), respectively. When a pre-equilibrated (1
h), equimolar solution of GAPDH and GDNF was analyzed by gel
filtration chromatography, two equally intense peaks were observed
(FIG. 14, solid line) with retention times identical to the
individual solutions. These data demonstrate that GDNF does not
interact with GAPDH in solution, thereby providing evidence that
DNSP-11 has an independent mechanism of action relative to mature
GDNF.
[0157] Taken together, these data indicate that DNSP-11 exhibits
potent neurotrophic actions analogous to GDNF, but likely signals
through pathways that do not directly involve the GFR.alpha.1
receptor.
[0158] The foregoing examples demonstrate that DNSP-11 shares many
physiological and neurotrophic properties with mature GDNF,
including neuroprotection and promoting differentiation in primary
dopamine neuron cell cultures; increasing dopamine release and
metabolism in vivo; and decreasing apomorphine-induced rotations
and enhancing dopamine function in the substantia nigra of 6-OHDA
lesioned rats.
Example 11: DNSP-11 Solubility and Stability
[0159] The backbone secondary structure of DNSP-11 was examined
using circular dichroism spectroscopy in the far-UV region (CD;
University of Kentucky Center of Structural Biology). The DNSP-11
spectrum (FIG. 15A) displayed a broad minimum mean residue
ellipticity (MRE) at 200 nm, indicative of a peptide that it is
dynamic and samples multiple confirmations. Small shoulders between
208-230 nm indicate that DNSP-11 appears to be sampling polyproline
II and other helical structures. Collectively, the spectrum of
DNSP-11 shows that it has characteristics of typical small,
soluble, functional peptides of similar length.
[0160] Reverse Phase HPLC (RP-HPLC; FIG. 15B); University of
Kentucky Center of Structural Biology) and electrospray mass
spectrometry (University of Kentucky Mass Spectrometry Facility)
were used to monitor at the stability of DNSP-11. DNSP-11 was
stored in citrate buffer (10 mM Citrate+150 mM NaCl, pH 5.0) at
-80.degree. C. and 37.degree. C. for 30 days. These temperatures
were chosen based on their relevance to long term storage and use
in future studies. The results of these studies showed that the
peptides were stable at both temperatures for one month without any
appreciable loss of peptide (FIG. 15C).
[0161] Our analysis of the effects of DNSP-11 on dopamine neurons
in the nigrostriatal system of the brain of young adult F344 rats
at 28 days following a single injection of the peptide,
demonstrated a surprising effect, i.e., an increase in basal tissue
levels of the dopamine metabolite 3,4-dihydroxyphenylacetic acid
(DOPAC, see FIG. 16). The 100% increase in DOPAC was unprecedented
in our numerous experiments over the past 20 years. In fact, we
have never seen a dopamine-altering agent, which increases the
metabolism of dopamine by 100% and this effect was seen to persist
for one month after a single injection of DNSP-11 into the
substantia nigra, which is the source of the dopamine-containing
fibers measured in the striatum. GDNF, which augmented the evoked
release of dopamine by over 100%, increased basal levels of DOPAC
by only 20-25% in young and aged rats (Herbert et al. J. Pharmacol.
Exp. Therapeut. (1996) 279:1181-1190, and Hebert and Gerhardt, J.
Pharmacol. Exp. Therapeut. (1997) 282:760-768). Based on the
results presented herein, and the knowledge that DOPAC is produced
when dopamine is metabolized by monoamine oxidase B, (an enzyme on
the outer membrane of mitochondria (Edmondson et al, Curr. Med Chem
(2004) 11(15:1983-93) and then the product of this reaction is
metabolized by aldehyde dehydrogenase (which resides in the cytosol
of cells) we reasoned that DNSP-11 increases mitochondrial
functions and thereby increases monoamine oxidase levels. The
following examples address this.
Example 12: DNSP-11: Distribution, Uptake and Half-Life in the
Brain
[0162] To assess the distribution, uptake and degradation of
DNSP-11 in the brain, young adult male F344 rats, as a test
organism, received injections of 30 .mu.g DNSP-11 in the substantia
nigra, hippocampus or cortex. They were euthanized by anesthesia
overdose at various time points from 30 minutes to 48 hrs later and
perfused through the heart with saline followed by
paraformaldehyde.
[0163] Our standard published procedures for immuncytochemical
staining were used (e.g. Gash D M et al., J Comp Neurol. 1995 Dec.
18; 363(3):345-58., Grondin et al., 2002; Ai et al., 2003). A
polyclonal antibody was generated against DNSP-11 in rabbits (Alpha
Diagnostic International, San Antonio, Tex.). Endogenous
peroxidases were inactivated by incubation with 0.2% hydrogen
peroxide (H.sub.2O.sub.2) for 10 minutes and background blocked
with 4% normal serum, 1% bovine serum albumin (BSA) for 1 hour.
Free floating sections were incubated in primary antisera. Sections
were then exposed to the appropriate biotinylated IgG (Vecto Labs,
Burlingame, Calif.) for 1 hour and then incubated in
avidin-biotin-peroxidase complex using Elite ABC Vectastain Kits
(Vector Labs) for 1 hour. Some sections were double-labeled using
procedures following our published procedures for
immunocytochemical staining to identify cells with two markers
(e.g. Ai et al., 2003).
[0164] Controls for immunostaining included the omission of primary
antibodies and replacement of primary antibodies with normal serum
of the same species.
[0165] Results: A 30 .mu.g bolus of DNSP-11 injected into the
mid-substantia nigra region using stereotaxic procedures spreads
.about.3 mm in the anterior-posterior plane and up to .about.2 mm
in the medial-lateral plane (FIG. 17) to cover most of the pars
compacta component of the nigra. DNSP-11 is taken up in the first
30 minutes following injection by neurons and their axonal and
dendritic processes. It is found in the cytoplasm and then
perinuclear area and nucleus. At 24 hours after injection, some
residual DNSP-11 can still be detected. There was no evidence of
DNSP-11 by 48 hours post peptide administration.
[0166] Stereotaxic injections of 30 .mu.g DNSP-11 were also made
into the striatum, hippocampus and cortex. Uptake was observed into
neurons in both areas. Pyramidal neurons in the cortex accumulated
DNSP-11.
[0167] In summary, DNSP-11 is taken up within 30 minutes by neurons
in all brain areas evaluated. The uptake sites appear to be
specific for axons, dendrites, synaptic terminals and perikarya of
nerve cells. DNSP-11 immunostaining is found in the cytoplasm and
then in the nucleus. The half-life of DNSP-11 in the rat brain is
under 24 hours. The areas of the brain studied (substantia nigra,
striatum, hippocampus and cortex) have major roles in cognitive and
motor functions. Tropic actions of DNSP-11 could protect these
brain areas from injury and/or promote restoration from disease and
injury processes.
Example 13: DNSP-11 Induced Changes in Genes Regulating
Mitochondria/Functions
[0168] Changes in expression of mitochondrial-associated genes in
the substantia nigra (SN) of three young adult (5 month old) male
F344 rats 48 hours following bilateral intranigral injections of
DNSP-11 into the substantial nigra was assessed as follows.
[0169] A 3 .mu.g/.mu.l DNSP-11 peptide solution was prepared in
citrate buffer and filter sterilized. Stereotaxic injections were
made of 30 .mu.g DNSP-11 in 10 ul citrate buffer into the
substantia nigra on each side of the brain. Controls received 10
.mu.g injections of vehicle. Forty-eight hours later, the animals
were euthanized, the brains quickly recovered and sectioned so that
the bilateral SN could be dissected out as one block of tissue and
snap frozen in liquid nitrogen. RNA was extracted from the SN
samples for gene array analysis, which was conducted on Affymetrix
Version II chips. A gene chip was run for each of the six rats:
three bilateral vehicle recipients, three bilateral 30 .mu.g
DNSP-11 recipients.
[0170] Genes regulating mitochondrial functions were identified as
the subset of genes on the microarray in the peptide-treated group
having expression levels that were significantly increased or
decreased as compared to the controls (Table 5). Fourteen genes
were significantly up-regulated and five were significantly
down-regulated in DNSP-11 recipients. One gene with increased
expression was Monoamine Oxidase B, a finding consistent with the
higher DOPAC levels mentioned earlier. A number of other genes with
increased expression are associated with protection against
oxidative damage: glutathione/glutaredoxin, glutathione peroxidase
and thioredoxin (Koehler et al., Antioxid Redox. Signal.,
8(5-6):813-22 (2006); Comhair & Erzurum Antioxid Redox Signal.,
7(1-2):72-9. (2005)). Catalase is an important enzyme converting
the strong oxidant hydrogen peroxide to water- and oxygen (Calderon
I L et al., Catalases are NAD(P)H-dependent teliurite reductases.
PLoS ONE. 1:e70 (2006 Dec. 20)). Peroxyredoxin is another
antioxidant (Rhee, Chae & Kim, Free Radic Biol Med. 2005 Jun.
15; 38(12):1543-52. Epub (2005 Mar. 24)). Increased levels of Park
7 (DJ-1) are protective against Parkinson's disease (Thomas &
Beal, Hum Mol Genet. 16 Spec No. 2:R183-94 (2007 Oct. 15)) and
increase levels of Presenilin 1 are believed to be protective
against Alzheimer's disease (Das, Front Biosci. 13:822-32 9 (2008
Jan. 1)). In both instances, it is a decreased or mutant form of
the gene that is closely linked to neurodegenerative diseases. The
cytochrome c oxidase subunits are components of the terminal
respiratory complex producing energy via oxidative
phosphorylation.
TABLE-US-00005 TABLE 5 Changes in expression level post DNSP-11
delivery FOLD SYMBOL DESCRIPTION PEPTIDE CONTROL P-VALUE CHANGE
GLRX2 glutaredoxin 2 3618.7 3472.2 <0.001 1.09 CASP8 caspase 8,
apoptosis-related cysteine 219.4 178.1 0.006 1.25 peptidase TXN2
thioredoxin 2 1511.9 1378.5 0.010 1.10 MAOB monoamine oxidase B
2199.8 1974.2 0.012 1.13 COX6A2 cytochrome c oxidase subunit Via
814.1 520.6 0.014 1.75 polypeptide2 GPX7 glutathione peroxidase 7
194.2 183.8 0.015 1.19 CAT catalase 2828.2 271a.0 0.015 1.09 PRDX5
peroxiredoxin 5 5569.8 4790.1 0.020 1.13 PSEN1 presenilin 1
(Alzheimer disease 3) 673.5 563.2 0.022 1.16 CASP3 caspase 3,
apoptosis-related cysteine 421.4 367.5 0.024 1.18 peptidase COX17
COX17 cytochrome c oxidase assembly 2326.1 2017.8 0.025 1.11
homolog (S. cerevisiae) PARK7 DJ-1 protective against Parkinson's
disease 5299.2 5159.4 0.032 1.02 COX6B1 cytochrome c oxidase
subunit Vib 7869.7 7536.6 0.044 1.04 polypeptide 1 (ubiquitous)
NDUFA7 NADH dehydrogenase (ubiquinone) 1 3125.4 2943.0 0.046 1.07
alpha subcomplex, 7, 14.5 kDa APP amyloid beta (A4) precursor
protein 9734.4 10117.2 0.006 -1.08 (peptidase nexin-II, Alzheimer
disease) MAPK9 mitogen-activated protein kinase 9 770.7 930.0 0.007
-1.21 MAPK10 mitogen-activated protein kinase 10 505.0 552.8 0.008
-1.08 BACEI beta-site APP-cleaving enzyme 1 451.6 510.6 0.016 -1.09
MAP2K4 mitogen-activated protein kinase kinase 4 2422.4 2744.4
0.043 -1.12
[0171] The caspases having increased expression are associated with
apotosis (Kataoka, Crit Rev Immunol. 25(1):31-58 (2005); Vassar,
Neuron 54(5):671-3 (2007)). Without wishing to be bound by theory,
the increased expression of low levels capases may reflect a
nonspecific inflammatory reaction to the mild physical injury
induced by the needle track and injection of material into the
substantia nigra.
[0172] The foregoing results indicate that DNSP-11 treatment
significantly effects the expression of genes regulating
mitochondrial functions. The changes in gene expression would be
neuroprotective against free radical oxidative damage to
mitochondria. This would decrease mitochondrial wear and tear from
oxidative respiratory processes producing energy, increasing the
functional lifespan of mitochondria in a neurons and synapses.
Example 14: DNSP-11 Increases State III Mitochondria/Respiration in
the Rat Nigrostriatal System
[0173] As our previous studies had demonstrated that injections of
30 .mu.g DNSP-11 into the substantia nigra had marked effects 28
days post administration with elevated levels of dopamine and
dopamine metabolites in the nigrostriatal system (substantia nigra
and its projections to the striatum), we quantified the effects of
DNSP-11 on mitochondria respiration and enzyme activity in the
nigrostriatal system of young adult F344 rats at 28 days post
injection.
[0174] Six five-month-old male F344 rats received bilateral
intranigral injections of 30 .mu.g DNSP-11. Six age and sex-matched
controls received injections of the same volume of vehicle (citrate
buffer). Twenty-eight days after test material administration, the
animals were euthanized by CO.sub.2 anesthesia and the brain
samples rapidly dissected. The striatum and substantia nigra were
isolated quickly and carefully using a rat brain matrix for F344
rats.
[0175] Mitochondrial respiration was assessed using a miniature
Clark-type electrode, in a sealed, thermostatic and continuously
stirred chamber. Mitochondria were added to the chamber to yield a
final protein concentration of 1 mg/ml. The substrate
concentrations were 5.0 mM/2.5 mM for glutamate/malate and
pyruvate/malate or 10 mM for succinate+2.5 .mu.M rotenone or
.alpha.-glycerophosphate. State 3 respiration was initiated by the
addition of 150 .eta.mols ADP. The respiratory control ratio was
calculated as respiration in the presence of ADP (state
3)/respiration in absence of ADP (state 4). ADP/0 ratios were
determined by dividing the amount of ADP phosphorylated during
State Ill respiration by the amount of oxygen consumed. NAD-linked
substrates, e.g. glutamate and pyruvate, utilize complexes I, Ill,
IV in their oxidation, succinate utilizes complexes II, Ill, IV and
.alpha.-glycerophosphate ultilizes III, IV. Thus impaired oxidation
of NAD-linked substrates, but normal oxidation of succinate or
.alpha.-glycerophosphate implies a defect at the level of complex
I. Impaired oxidation of both NAD-linked and succinate oxidation
implies a defect in both complex I and II and/or in complex III and
IV which can be elucidated by the use of a-glycerophosphate.
[0176] The chamber was also equipped with fluorescence/absorbance
probes which allow us to also measure simultaneously ROS production
in real-time with all other parameters. ROS production was measured
using the H.sub.2O.sub.2 indicator dichlorodihydrofluorescein
diacetate (H.sub.2DCFDA, Molecular Probes). Ten .mu.M H.sub.2DCFDA,
which is made fresh before each use, was added to the chamber and
the relative amount of mitochondria) H.sub.2O.sub.2 and free
radical production measured as an increase in fluorescence. Again
the same rationale as above can be used to pinpoint the source of
ROS production. Additionally, ROS production was monitored over
time in a Synergy HT plate reader or a Shimadzu RF-5301
spectrofluorimetre with stirred and water-jacketted cuvett holders
(excitation 490.eta.m, emissions 526.eta.m; ex550.eta.m,
em590.eta.m, respectively) at 37.degree. C. for 15 min in the
presence of 10 .mu.M H.sub.2DCFDA or Amplex Red, a H.sub.2O.sub.2
indicator that is extramitochondrial. Controls include the addition
of the electron transport chain inhibitor antimycin (complex III
inhibitor, yields maximum ROS production independent of
.DELTA..PSI.), oligomycin (inhibits ATPase yielding maximum
.DELTA..PSI.-dependent ROS production) and the uncoupler FCCP
(inhibits all .DELTA..PSI.-dependent ROS production).
[0177] The mitochondria are freeze-thawed and sonicated three times
for measuring all the complexes activities. Complex I (NADH
dehydrogenase) assay is performed in 2.5 mM KPO.sub.4 buffer (pH
7.2) containing mitochondrial protein (6 .mu.g), 5 mM MgCl.sub.2, 1
mM KCN, 1 mg/ml BSA, and 150 .mu.M NADH at 30.degree. C., the
reaction initiated by addition of coenzyme Q-1 (50 .mu.M). In this
reaction ubiquinone 1 was the final electron accepter. The decrease
in NADH absorbance at 340 .eta.m was monitored. The assay was also
performed in the presence of rotenone (10 .mu.M) to determine the
rotenone-insensitive and the rotenone-sensitive complex I enzyme
activity. Complex II (succinate dehydrogenase) activity was
measured by the rate of reduction of 2,6-Dichloroindophenol. The
reaction mixture contained 100 mM KPO.sub.4 buffer, 20 mM
succinate, 10 .mu.M EDTA, 0.01% Triton, 1 .mu.g/100 coenzyme Q2
containing mitochondria) protein (6 .mu.g) at 30.degree. C. and the
reaction was initiated by the addition of 0.07%
2,6-Dichloroindophenol. Decreased in absorbance was monitored at
600 .eta.m. Complex IV (cytochrome c oxidase) activity was measured
in 10 mM KPO.sub.4 buffer and 50 .mu.M reduced cytochrome c. The
reaction was initiated by addition of 6 .mu.g mitochondria)
protein. Rate of oxidation of cytochrome c was measured by
measuring the decrease in absorbance of reduced cytochrome c,
observed at 550 nm.
[0178] As shown in FIG. 18, there was a trend towards an increase
in State III oxidative phosphorylation at 28 days post treatment in
the substantia nigra. However, with an n=2, the difference was not
significant with a two-tailed t-test. The effects reached
statistical significance in the striatum, which is heavily
innervated by dopamine fibers from the substantia nigra forming
synapses on striatial medium spiny neurons. Evidence described in
Example 12 indicates that DNSP-11 was taken up within 30 minutes
into neuritic processes and cell bodies of neurons. Soon
thereafter, immunoreactive DNSP-11 was found in the nucleus. The
effects at 28 days on dopamine and metabolite levels and on
mitochondria demonstrate that DNSP-11 treatment initiates genetic
changes that last for long periods, at least one month, and without
wishing to be bound by theory, this may occur perhaps through
receptors involving transcribing factors.
[0179] Within 30 minutes following a 30 ug injection of DNSP-11
into the F344 rat substantia nigra, the broad distribution of the
compound through the substantia nigra (SN) region of the midbrain
was evident (FIG. 17, panels A, B). At higher magnification (FIG.
17 panels C, D) uptake of the peptide by neurons (arrows) could be
discerned. At very high magnification (FIG. 17 panel E),
punctate-immunoreactive staining of DNSP-11 was present in neuritic
processes, cytoplasm and the perinuclear area of the cell body
(arrows). The pattern of immunoreactivity was similar at 90 minutes
post injection (FIG. 17 panel B), with prominent labeling in
DNSP-11 in cells and neuritic processes (FIG. 17, panel D).
Immunostaining was more sensitive using fluorescent techniques
(FIG. 17, panel F), highlighting DNSP-11 immunoreactivity in the
cytoplasm and nuclei of neurons. The cells in F were double-labeled
for the neuronal marker NeuN and DNSP-11.
[0180] By improving mitochondrial functions in neurons and their
synapses, DNSP-11 treatment could significantly restore neural
networks affected in neurodegenerative diseases, including
Alzheimer's disease and Parkinson's disease, improving cognitive
functions in the former and improved motor functions in the
latter.
Example 15: The In Vitro Studies and In Vivo Measures of the
Neurotrophic/Mitochondrogenic Effects of DNSP-11 LED Us to
Investigate the Potential Neurorestorative Properties of DNSP-11 to
Damaged Dopamine Neurons in a Unilateral Rat Model of PD
[0181] Fischer 344 rats received dual-site unilateral injections of
6-OHDA to produce extensive destruction of the ascending
dopaminergic system that resulted in a greater than 99% depletion
of striatal dopamine content ipsilateral to the site of the 6-OHDA
injections. Rats were tested 3-4 weeks after the injection of
6-OHDA using low-dose (0.05 mg/kg, i.p.) apomorphine to induce
rotational behavior. In rats that rotated greater than 300 turns/60
minutes, 30 .mu.g of DNSP-11 was injected into the ipsilateral
substantia nigra. DNSP-11 produced a significant .about.50%
decrease in apomorphine-induced rotational behavior that was
significant 1 week after administration and this effect was
maintained for at least 4 weeks after DNSP-11 (FIG. 19A). At 5
weeks, the substantia nigra and striatum from each rat was analyzed
by high performance liquid chromatography coupled with
electrochemical detection. A single injection of DNSP-11 was found
to significantly increase levels of dopamine and the dopamine
metabolite, DOPAC, by .about.100% in the substantia nigra,
supporting that DNSP-11 has a powerful
neurotrophic-like/mitochondrogenic restorative effect on dopamine
neurons in this animal model of late stage PD (FIG. 19B).
[0182] In summary, the evidence reported in this patent application
demonstrates the ability of DNSP-11 treatment to improve
mitochondrial functions and supports the ability of DNSP-11
treatment to promote behavioral restoration in Alzheimer's disease,
Parkinson's disease and aging processes. [0183] Our results
demonstrate that DNSP-11 is taken up by neurons in the cortex,
hippocampus and substantia nigra, areas important in cognitive and
motor functions; [0184] Our results demonstrate that DNSP-11
significantly increases the expression of genes associated with
mitochondrial functions in the brain, including genes for proteins
that protect mitochondria from oxidative damage leading to
functional deterioration; [0185] Our results demonstrate that
DNSP-11 increases energy production in brain mitochondria for
extended periods. [0186] Increased energy production in
mitochondria in synapses is posited to promote restoration of
neural circuitry leading to restoration of cognitive and motor
functions.
[0187] While the present invention has been described with
reference to specific embodiments, this application is intended to
cover those various changes and substitutions that may be made by
those of ordinary skill in the art without departing from the
spirit and scope of the appended claims.
[0188] The publications discussed herein are provided solely for
their disclosure prior to the filing date of the present
application. Nothing herein is to be construed as an admission that
the present invention is not entitled to antedate such publication
by virtue of prior invention. Further, the dates of publication
provided may be different from the actual publication dates, which
may need to be independently confirmed. All publications cited
herein are hereby incorporated by reference in their entirety.
Sequence CWU 1
1
151134PRTHomo sapiens 1Ser Pro Asp Lys Gln Met Ala Val Leu Pro Arg
Arg Glu Arg Asn Arg1 5 10 15Gln Ala Ala Ala Ala Asn Pro Glu Asn Ser
Arg Gly Lys Gly Arg Arg 20 25 30Gly Gln Arg Gly Lys Asn Arg Gly Cys
Val Leu Thr Ala Ile His Leu 35 40 45Asn Val Thr Asp Leu Gly Leu Gly
Tyr Glu Thr Lys Glu Glu Leu Ile 50 55 60Phe Arg Tyr Cys Ser Gly Ser
Cys Asp Ala Ala Glu Thr Thr Tyr Asp65 70 75 80Lys Ile Leu Lys Asn
Leu Ser Arg Asn Arg Arg Leu Val Ser Asp Lys 85 90 95Val Gly Gln Ala
Cys Cys Arg Pro Ile Ala Phe Asp Asp Asp Leu Ser 100 105 110Phe Leu
Asp Asp Asn Leu Val Tyr His Ile Leu Arg Lys His Ser Ala 115 120
125Lys Arg Cys Gly Cys Ile 130217PRTArtificial SequenceDescription
of Artificial Sequence Synthetic peptide 2Glu Arg Asn Arg Gln Ala
Ala Ala Ala Asn Pro Glu Asn Ser Arg Gly1 5 10 15Lys35PRTArtificial
SequenceDescription of Artificial Sequence Synthetic peptide 3Phe
Pro Leu Pro Ala1 5411PRTArtificial SequenceDescription of
Artificial Sequence Synthetic peptide 4Pro Pro Glu Ala Pro Ala Glu
Asp Arg Ser Leu1 5 105402DNAHomo sapiensCDS(1)..(402) 5tca cca gat
aaa caa atg gca gtg ctt cct aga aga gag cgg aat cgg 48Ser Pro Asp
Lys Gln Met Ala Val Leu Pro Arg Arg Glu Arg Asn Arg1 5 10 15cag gct
gca gct gcc aac cca gag aat tcc aga gga aaa ggt cgg aga 96Gln Ala
Ala Ala Ala Asn Pro Glu Asn Ser Arg Gly Lys Gly Arg Arg 20 25 30ggc
cag agg ggc aaa aac cgg ggt tgt gtc tta act gca ata cat tta 144Gly
Gln Arg Gly Lys Asn Arg Gly Cys Val Leu Thr Ala Ile His Leu 35 40
45aat gtc act gac ttg ggt ctg ggc tat gaa acc aag gag gaa ctg att
192Asn Val Thr Asp Leu Gly Leu Gly Tyr Glu Thr Lys Glu Glu Leu Ile
50 55 60ttt agg tac tgc agc ggc tct tgc gat gca gct gag aca acg tac
gac 240Phe Arg Tyr Cys Ser Gly Ser Cys Asp Ala Ala Glu Thr Thr Tyr
Asp65 70 75 80aaa ata ttg aaa aac tta tcc aga aat aga agg ctg gtg
agt gac aaa 288Lys Ile Leu Lys Asn Leu Ser Arg Asn Arg Arg Leu Val
Ser Asp Lys 85 90 95gta ggg cag gca tgt tgc aga ccc atc gcc ttt gat
gat gac ctg tcg 336Val Gly Gln Ala Cys Cys Arg Pro Ile Ala Phe Asp
Asp Asp Leu Ser 100 105 110ttt tta gat gat aac ctg gtt tac cat att
cta aga aag cat tcc gct 384Phe Leu Asp Asp Asn Leu Val Tyr His Ile
Leu Arg Lys His Ser Ala 115 120 125aaa agg tgt gga tgt atc 402Lys
Arg Cys Gly Cys Ile 1306211PRTHomo sapiens 6Met Lys Leu Trp Asp Val
Val Ala Val Cys Leu Val Leu Leu His Thr1 5 10 15Ala Ser Ala Phe Pro
Leu Pro Ala Gly Lys Arg Pro Pro Glu Ala Pro 20 25 30Ala Glu Asp Arg
Ser Leu Gly Arg Arg Arg Ala Pro Phe Ala Leu Ser 35 40 45Ser Asp Ser
Asn Met Pro Glu Asp Tyr Pro Asp Gln Phe Asp Asp Val 50 55 60Met Asp
Phe Ile Gln Ala Thr Ile Lys Arg Leu Lys Arg Ser Pro Asp65 70 75
80Lys Gln Met Ala Val Leu Pro Arg Arg Glu Arg Asn Arg Gln Ala Ala
85 90 95Ala Ala Asn Pro Glu Asn Ser Arg Gly Lys Gly Arg Arg Gly Gln
Arg 100 105 110Gly Lys Asn Arg Gly Cys Val Leu Thr Ala Ile His Leu
Asn Val Thr 115 120 125Asp Leu Gly Leu Gly Tyr Glu Thr Lys Glu Glu
Leu Ile Phe Arg Tyr 130 135 140Cys Ser Gly Ser Cys Asp Ala Ala Glu
Thr Thr Tyr Asp Lys Ile Leu145 150 155 160Lys Asn Leu Ser Arg Asn
Arg Arg Leu Val Ser Asp Lys Val Gly Gln 165 170 175Ala Cys Cys Arg
Pro Ile Ala Phe Asp Asp Asp Leu Ser Phe Leu Asp 180 185 190Asp Asn
Leu Val Tyr His Ile Leu Arg Lys His Ser Ala Lys Arg Cys 195 200
205Gly Cys Ile 2107192PRTHomo sapiens 7Phe Pro Leu Pro Ala Gly Lys
Arg Pro Pro Glu Ala Pro Ala Glu Asp1 5 10 15Arg Ser Leu Gly Arg Arg
Arg Ala Pro Phe Ala Leu Ser Ser Asp Ser 20 25 30Asn Met Pro Glu Asp
Tyr Pro Asp Gln Phe Asp Asp Val Met Asp Phe 35 40 45Ile Gln Ala Thr
Ile Lys Arg Leu Lys Arg Ser Pro Asp Lys Gln Met 50 55 60Ala Val Leu
Pro Arg Arg Glu Arg Asn Arg Gln Ala Ala Ala Ala Asn65 70 75 80Pro
Glu Asn Ser Arg Gly Lys Gly Arg Arg Gly Gln Arg Gly Lys Asn 85 90
95Arg Gly Cys Val Leu Thr Ala Ile His Leu Asn Val Thr Asp Leu Gly
100 105 110Leu Gly Tyr Glu Thr Lys Glu Glu Leu Ile Phe Arg Tyr Cys
Ser Gly 115 120 125Ser Cys Asp Ala Ala Glu Thr Thr Tyr Asp Lys Ile
Leu Lys Asn Leu 130 135 140Ser Arg Asn Arg Arg Leu Val Ser Asp Lys
Val Gly Gln Ala Cys Cys145 150 155 160Arg Pro Ile Ala Phe Asp Asp
Asp Leu Ser Phe Leu Asp Asp Asn Leu 165 170 175Val Tyr His Ile Leu
Arg Lys His Ser Ala Lys Arg Cys Gly Cys Ile 180 185
19088PRTArtificial SequenceDescription of Artificial Sequence
Synthetic peptide 8Phe Pro Leu Pro Ala Gly Lys Arg1
5914PRTArtificial SequenceDescription of Artificial Sequence
Synthetic peptide 9Pro Pro Glu Ala Pro Ala Glu Asp Arg Ser Leu Gly
Arg Arg1 5 101020PRTArtificial SequenceDescription of Artificial
Sequence Synthetic peptide 10Glu Arg Asn Arg Gln Ala Ala Ala Ala
Asn Pro Glu Asn Ser Arg Gly1 5 10 15Lys Gly Arg Arg
20116PRTArtificial SequenceDescription of Artificial Sequence
Synthetic peptide 11Phe Pro Leu Pro Ala Gly1 51212PRTArtificial
SequenceDescription of Artificial Sequence Synthetic peptide 12Pro
Pro Glu Ala Pro Ala Glu Asp Arg Ser Leu Gly1 5 101318PRTArtificial
SequenceDescription of Artificial Sequence Synthetic peptide 13Glu
Arg Asn Arg Gln Ala Ala Ala Ala Asn Pro Glu Asn Ser Arg Gly1 5 10
15Lys Gly1416PRTArtificial SequenceDescription of Artificial
Sequence Synthetic peptide 14Lys Arg Pro Pro Glu Ala Pro Ala Glu
Asp Arg Ser Leu Gly Arg Arg1 5 10 151522PRTArtificial
SequenceDescription of Artificial Sequence Synthetic peptide 15Arg
Arg Glu Arg Asn Arg Gln Ala Ala Ala Ala Asn Pro Glu Asn Ser1 5 10
15Arg Gly Lys Gly Arg Arg 20
* * * * *