ABSTRACT
Keywords
Ageing; Animal; Human; Peptides; Pharmacology; Physiology;
Therapeutic use; Immunity; Pineal Body; Retina; Retinal degeneration
A
technology has been developed for manufacturing of biologically
active complex peptide preparations from extracts of different
tissues. In particular, the pineal preparation (Epithalamin)
augments the in vitro outgrowth of explants from the pineal
gland but not from other tissues, the latter being stimulated
by peptide preparations from respective tissues. Epithalamin
increases melatonin production by the pineal gland of rats,
improves immunological parameters in rats and mice, produces
anticarcinogenic effects in different experimental models, stimulates
antioxidant defenses, and restores the reproductive function
in old rats. These effects are combined in the ability of Epithalamin
to increase the lifespan in rats, mice, and fruit flies. Many
of these effects are reproduced in clinical trials, which have
demonstrated the geroprotector activity of Epithalamin in humans.
Among the effects of the thymic preparation Thymalin, those
related to its ability to stimulate immunity are the most prominent.
This ability is associated with anticarcinogenic and geroprotector
activities. Clinical trials of the peptide preparations obtained
from other organs including the prostate, the cerebral cortex,
and the eye retina, have demonstrated beneficial effects reflected
by the improvement of the conditions of respective organs. Based
on the data about the amino acid compositions of the peptide
preparations, novel principles of the design of biologically
active short peptides possessing tissue-specific activities
has been developed. Dipeptides specific for the thymus and tetrapeptides
specific for the heart, liver, brain cortex, and pineal glands
stimulate the in vitro outgrowth of explants of respective organs.
Interestingly, for eye retina and the pineal gland, a common
tetrapeptide Ala-Glu-Asp-Gly (Epitalon) has been designed, probably
reflecting the common embryonal origin of these two organs.
Epitalon reproduces the effects of Epithalamin including those
related to its geroprotector activity. In particular, Epitalon
increases the lifespan of mice and fruit flies and restores
the circadian rhythms of melatonin and cortisol production in
old rhesus monkeys. At the same time, Epitalon prolongs the
functional integrity of the eye retina in Campbell rats with
hereditary Retinitis Pigmentosa and improves the visual functions
in patients with pigmental retinal degeneration. Changes in
gene expression were observed to be produced by the short peptide
preparations. Therefore, the effects of Epitalon are suggested
to be mediated by transcriptional machinery common for the pineal
gland and the retina and, probably, for regulation of melatonin
production in fruit flies. Based on three decades of studies
of the peptide preparations, the peptide theory of ageing has
been put forward. According this theory, ageing is an evolutionary
determined biological process of changes in gene expression
resulting in impaired synthesis of regulatory and tissue-specific
peptides in organs and tissues, which provokes their structural
and functional changes and the development of diseases. Correspondingly,
correction of such disorders by means of stimulation of peptide
production in the organism or through their delivery can promote
the normalisation of disturbed body functions.
TABLE OF CONTENTS 'PEPTIDES AND AGEING'
Vladimir
Kh. Khavinson
FOREWORD
. 5
ABSTRACT . 11
INTRODUCTION . 13
CHAPTER 1.
Aspects of peptide biology
1.1. General considerations. 19
1.2. Regulatory peptides . 21
1.3. Ageing and peptides . 32
CHAPTER
2.
Experimental studies of the anti-ageing effects of "
peptide preparations
2.1. General characteristic of peptide preparations
2.1.1. Complex peptide preparations (Cytomedins) 41
2.1.2. Synthetic small peptides (Cytogens) 44
2.2. Effects of peptide preparations on ageing, longevity,
and spontaneous carcinogenesis
2.2.1. Epithalamin, ageing rate, and lifespan 47
2.2.2. Effects of Epithalamin and Thymalin on lifespan and
spontaneous carcinogenesis in rodents 47
2.2.3. Epitalon, ageing rate, and lifespan 50
2.2.4. Effects of Epitalon, Thymogen, and Vilon on lifespan
and
spontaneous carcinogenesis in rodents 52
2.3. Effects of peptide preparations on the factors and
correlates of ageing
2.3.1. Antioxidant defences 55
2.3.1.1. Effects of Epithalamin and melatonin on free radical
processes 55
2.3.1.2. Effects of Vilon and Epitalon on free radical processes
58
2.3.2. Immunity 59
2.3.2.1. Effects of Thymalin 59
2.3.2.2. Effects of Thymogen and Vilon 60
2.3.2.3. Comparative studies of immunomodulating activities
of
Thymalin, Thymogen, and Vilon 62
2.3.3. Carcinogenesis
2.3.3.1. Effects of Epithalamin and Thymalin on induced
carcinogenesis in rodents 63
2.3.3.2. Effects of Epitalon, Thymogen, and Vilon on induced
carcinogenesis in rodents 65
2.3.4. Tissue regeneration and degeneration
2.3.4.1. Tissue-specific effects of peptide preparations in
tissue
and cell cultures 67
2.3.4.2. Effects of peptide preparations on tissue regeneration
in vivo 75
2.3.4.3. Effects of Epitalon on visual functions in Campbell
rats
with hereditary pigmented retinal degeneration 77
2.3.5. Neuroendocrine system
2.3.5.1. Neuroendocrine effects of Thymalin, Thymogen, and
Vilon 80
2.3.5.2. Effects of Epithalamin on the reproductive system
80
2.3.5.3. Effects of Epithalamin and Epitalon on the pineal
gland 82
2.3.6. Gene expression . 85
2.3.7. Mitochondrial functions . 88
2.4. Summary and conclusions . 90
CHAPTER 3.
Clinical studies of peptide preparations
3.1. Epithalamin
3.1.1. Hereditary predisposition to age-associated diseases
93
3.1.2. Age-associated diseases 96
3.1.3. Non-insulin-dependent diabetes mellitus (NIDDM) 98
3.1.4. Premature senescence 98
3.1.5. Climacteric cardiomyopathy 99
3.1.6. Cancer after radio- or chemotherapy 100
3.1.7. Aspirin-induced asthma 102
3.1.8. Asthenic syndrome 104
3.2. Thymalin
3.2.1. Conditions after thymectomy 105
3.2.2. Age-associated diseases 105
3.3.3. Cancer after radio- or chemotherapy 106
3.3. Thymogen
3.3.1. Infectious diseases 109
3.3.2. Immune impairments 110
3.3.3. Other conditions 113
3.4. Vilon
3.4.1. Chronic inflammations and infections 115
3.4.2. Cancer after radiation therapy 116
3.5. Cortexin
.5.1. Circulatory encephalopathies 117
3.6. Retinalamin
3.6.1. Retinalamin in treating eye diseases 119
3.6.2. Retinalamin in combination with other Cytomedin
preparations in treating eye diseases 120
3.7. Prostatilen
3.7.1. Prostate adenoma 121
3.7.2. Prostatitis 122
3.7.3. Male sexual dysfunctions 124
3.8. Summary and conclusions. 125
GENERAL DISCUSSION. 127
ACKNOWLEDGEMENT. 130
REFERENCES. 131
Foreword
Scanning
of the latest issues of periodicals specialised in ageing research
may draw a gerontologist’s attention to a number of publications
that describe the effects of peptide preparations developed
in Russia at the St. Petersburg Institute of Bioregulation and
Gerontology. The authors claim that their products are able
to render a whole range of effects generally believed to be
beneficial for the inhibition of ageing and age-associated diseases.
It is noteworthy that some of the preparations are included
into the State Russian Pharmacopoeia and used in clinics for
good as it comes out. Moreover, the authors report that some
of the preparations increase the lifespan and slow down ageing
rate in a bewilderingly broad range of experimental settings:
from mature Drosophila flies whose larvae have been treated
with an unprecedentedly low dose of the preparations to rats
and mice treated lifelong. Among other outcomes it has been
reported that a synthetic tetrapeptide designed based on amino
acid composition of a mixture of peptides extracted from the
pineal gland could restore melatonin production in old monkeys,
reduce spontaneous and induced tumour incidence in rats and
mice, enhance antioxidant defence in flies, rats, and humans,
and slow down retinal degeneration in rats with Retinitis Pigmentosa.
All this is a result of more than thirty years of research effort,
which mostly remained concealed being reported in obscure Russian
journals unavailable to the Western audience. Now, thanks to
this book, for which this foreword has been written, the entire
range of evidences that substantiate the advances achieved by
the developers of the preparations in question is open to anyone.
So, it is up to readers to decide whether they believe what
they read or not. Of course, although the book fills many gaps
evident from the first glance at scattered publications, it
exposes other gaps not filled by research. It is only quite
recently that the most advanced methods of modern biology including
DNA-microarray have been used to get a better insight into mechanisms
of action of the peptides described in this book. Hopefully,
it will stimulate efforts to control the data expose, confirm
the results obtained, regarding the biological and clinical
activity of the peptide developed in St.Petersburg as well as
to understand the mechanisms of action of these preparations.
Professor
Mario Passeri
President
European Region
International Association of Gerontology
Introduction
Evolutionary
processes in very different systems ranging from the populations
of living organisms to scientific disciplines are based on a
random search for novelties and subsequent selection and saving
of the most beneficial findings. Mathematical modeling demonstrates
that in situation where evolutionary changes in relatively isolated
subsystems are accumulating independently and this alternates
with periods of removed barriers and free information flow,
the entire system develops faster than without temporal restrictions
for such flow. This is what occurs in present day science. Russian
researchers have long been working in a relative isolation from
the world scientific community and developed their own original
approaches in some research areas. The time has come to exchange
ideas. Russian science has gained a unique experience in several
fields of biology and, in particular, in studying and practical
usage of biologically active peptides.
Intensive investigation of biologically active peptides started
all over the world some thirty years ago after the discovery
of endogenous opioids and in connection with searching for thymic
regulators of immunity. Methods for obtaining biologically active
peptide extracts from the thymus were developed almost simultaneously
by several research teams in the USA, Western Europe, and Russia,
in particular, by the author of this book in collaboration with
V. G. Morozov. Then the ways of scientists on different sides
of the iron curtain diverged. Western researchers followed the
trodden paths of isolation of specific substances, their molecular
identification, determination of their target cells, receptors,
intracellular signal transmission pathways, etc. Russian scientists
also isolated several defined biologically active thymic peptides,
which were partially identical to those isolated by foreign
researchers. However, Russian peptide research was guided not
only by technologies, which lagged increasingly behind, but
also by concepts, which emerged soon after obtaining the first
data about biological effects of peptide extracts from the thymus
and other organs and tissues.
V. Kh. Khavinson and V. G. Morozov suggested that the extracts
they obtained could contain peptides involved in information
exchange between cells. Such extracts were named “cytomedins”
(from Greek cytos – ‘cell’ and Latin mediator)
[1, 2]. At first, these products were extracted from the thymus,
hypothalamus, and epiphysis and, later, from virtually all organs
and tissues. The method of obtaining cytomedins is described
in Chapter 2 of this book. These preparations are named according
to tissues and organs of their origin. For example, Epithalamin
is the name for a cytomedin preparation from the epithalamic
area of the brain including the pineal gland, Thymalin is for
a thymic Cytomedin preparation, Cordialin is for heart peptides,
and so on. All cytomedins are complexes of alkaline polypeptides
with molecular weight usually within 10 kDa.
The very first studies of Cytomedins have revealed that Epithalamin,
a complex of pineal peptides, contains components that can reduce
one of important manifestations of ageing in mammals, i. e.,
the decreased sensitivity of the hypothalamo-pituitary system
to estrogens. Administration of Epithalamin to old animals promoted
the restoration of their reproductive functions (section 2.3.5.2
of the book). Cytomedins from the pineal gland and thymus were
shown to have an antitumour activity (sections 2.2. and 2.3.3).
Thymic cytomedins (Thymalin) were shown to take a part in regulation
of immunity (section 2.3.2).
Another essential property of cytomedins is their ability to
activate antioxidant defences of the organism (section 2.3.1),
which is important for protection against cancer and ageing.
Ageing and the development of complications of irradiation have
much in common: in both cases lipid peroxidation is activated,
immunity is depressed, the risk of tumour development increases,
and the resistance of the organism to unfavourable factors declines.
Consequently, cytomedins can be regarded as natural immuno-,
gero-, and radioprotectors.
Many years of research confirm the suggestion that cytomedins
exert their maximal effect upon the organ they have been isolated
from (section 2.1). A model of development of pathological conditions
has been suggested assigning a key role in their pathogenesis
to disorders in cytomedin-mediated regulation. This refers to
the complex of pathologic processes associated with ageing.
According to the cytomedin concept, ageing is an evolutionary
determined biological process of age-related changes in gene
expression resulting in impaired synthesis of regulatory and
tissue-specific peptides in organs and tissues, which provokes
their structural and functional changes and the development
of diseases [3]. Correspondingly, correction of such disorders
by means of stimulation of Cytomedin production in the organism
or through their delivery from outside is expected to promote
the normalisation of disturbed body functions [4].
The Cytomedin concept emerged at the time when biology lacked
grounds it stands on now as a result of technological developments.
Nevertheless, this concept proved to be an efficient guide to
action, as is evidenced by results obtained.
Experiments with rats, mice, and fruit flies Drosophila melanogaster
have revealed the potential of Epithalamin and Thymalin to significantly
increase longevity and inhibit the development of age-related
disorders (section 2.2).
Much experience has been gained in using Epithalamin and Thymalin
in geriatrics (Chapter 3). Based on many years of clinical trials
carried out at the Institute of Gerontology of the Ukrainian
Academy of Sciences, these two preparations are rated among
the few that satisfy human geroprotector criteria [5]. Epithalamin
has been shown to promote the normalisation of estradiol, follicle
stimulating hormone, and cortisol levels in climacteric women.
Patients with non-insulin dependent diabetes mellitus show a
decrease in blood glucose after the administration of Epithalamin.
In oncology, Epithalamin is useful in treating patients having
hormone-dependent tumours. Administration of this drug simultaneously
with radio- and chemotherapy increases blood lymphocyte counts,
improves the general conditions of patients, and mitigates intoxication
symptoms. Administration of Epithalamin to elderly patients
is accompanied by an increase in the total antioxidation activity
of blood serum, decrease in lipid peroxidation products, and
increases in superoxide dismutase and glutathione peroxidase
activities.
Thymalin has been successfully used to treat patients after
thymectomy and elderly patients with thymus involution (section
3.2).
Trials on the effectiveness of Cortexin (a complex peptide preparation
from the cerebral cortex) in neurological practice have demonstrated
its positive effects in elderly patients with brain dysfunctions
caused by organic lesions of the brain and disturbed cerebral
circulation (section 3.5).
Eyesight disorders are usual in ageing. The problem of a therapy
for retinal degeneration is of an even greater general medical
and social significance. The use of Retinalamin (a peptide preparation
from the retina) in such cases has been shown to stimulate functions
of photoreceptors and other cellular elements of the retina
and promote the restoration of retinal photosensitivity. The
drug normalises blood vessel permeability, diminishes manifestations
of inflammation, and stimulates reparative processes in injured
eye retina (section 3.3).
Treatment of patients with chronic prostatitis and benign hyperplasia
(adenoma) of the prostate is among the most burning problems
of present day geriatric urology and andrology. The use of Prostatilen,
a polypeptide preparation from animal prostate, has been shown
to reduce a number of symptoms of these diseases and improve
male sexual performance (section 3.7).
Based on studies of cytomedins, a principally new approach to
searching for physiologically active peptides and for their
synthesis has been worked out. The approach implies the analysis
of amino acid composition of complex polypeptide preparations,
determination of the most prevalent amino acids in each preparation,
and the design of primary structures of small peptides consisting
of these amino acids (section 2.1.2). A technology for manufacturing
of peptide regulators of thymus, brain, pineal gland, retina,
and liver cells has been developed based on this approach.
Comparative studies of the biological activities of complex
polypeptide preparations and respective synthetic peptides revealed
parallelisms between their effects on various organs and tissues
(Chapter 2). For example, Epitalon (Ala-Glu-Asp-Gly) as well
as Epithalamin stimulates the pineal gland (section 2.3.5.3).
It is remarkable that peptides designed on the basis of Epithalamin
and Retinalamin compositions appear to be identical, which is
consistent with the histogenetic kinship of respective organs
and points at common mechanisms of their peptidergic regulation.
Administration of Epitalon to rats with hereditary pigmental
degeneration of the retina prolongs the integrity of its structure
and functions (section 2.3.4.4). Another synthetic peptide,
Vilon (Lys-Glu), designed on the basis of Thymalin, a thymic
peptide extract, stimulates the expression of IL-2 gene in lymphocytes,
which usually decreases with age (section 2.3.6). Intramuscular
administration of Cortagen (Ala-Glu-Asp-Pro) designed on the
basis of Cortexin amino acid composition stimulates the structural
and functional restoration of damaged peripheral nerves (section
2.3.4.3).
During thirty years of studying the role of peptides in ageing
and of developing peptide geroprotectors, 23 bioregulatory preparations
have been invented. Six of them are included in the State Pharmacopeia
of the Russian Federation and 17 are licensed in Russia as biologically
active food supplements.
The major part of this book is dedicated to the description
and analysis of the results obtained in studies of Cytomedins
and synthetic peptides designed on their basis. In the most
recent experiments, the latest technological developments of
molecular biology were employed, such as DNA-microarray technique
for studying the effects of synthetic peptides on gene expression
(section 2.3.6). However, it is obvious that the more convincing
proof of the heuristic potency of cytomedin concept is provided
through generally recognised achievements of molecular biology,
the greater is the necessity to find correlations between Cytomedin
concept and established facts and concepts of regulatory peptide
biology. Issues relevant to that problem will be considered
in Chapter 1 of this book within a minimal scope consistent
with the format of this publication.
Approval of Ethic Committee
Following
standard pre-clinical and clinical studies, peptide bioregulators
were approved for medical application by the USSR Ministry
of Health (later on Russian Ministry of Health), whose competence
covered observation of ethic norms in studying new medicine:
1. Thymalin – USSR Ministry of Health Instruction # 1008
of 10.11.1982 (Reg. # 82.1008.8)
2. Thymogen – USSR Ministry of Health Instruction # 250
of 19.06.1990 (Reg. # 90.250.1)
3. Epithalamin – USSR Ministry of Health Instruction
# 250 of 19.06.1990 (Reg. # 90.250.6)
4. Prostatilen – Russian Ministry of Health Instruction
# 329 of 17.12.1992 (Reg. # 92.329.7)
5. Cortexin – Russian Ministry of Health Instruction
# 136 of 19.04.1999 (Reg. # 99.136.14)
6. Retinalamin – Russian Ministry of Health Instruction
# 212 of 01.06.1999 (Reg. # 99.212.7)
Ethic committee at the Federal department of the drug quality,
efficacy and safety control was established in Russia in 1998.
Peptide Vilon was covered by the Ethic committee approval
in 2001 (Protocol # 20 of 28.11.2001).
Prof.
F.I. Komarov, M.D., Ph.D.
Chairman of the Ethic committee
Active member of the Russian Academy of
Medical Sciences
Vol. 23 Supplement 3 - Special Issue, 2002
Neuroendocrinology Letters www.nel.edu
More
information available: publisher@nel.edu
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