Epithalamin Research & Studies

Epitalon, also known as Epithalon or Epithalone, is a tetrapeptide, Ala-Glu-Asp-Gly (AEDG), which was synthesized based on the amino acids composition of Epithalamin, a bovine pineal gland extract, prior to its discovery in pineal gland polypeptide complex solution. During the last 25 years, this compound has been extensively studied using in vitro, in vivo, and in silico methods. The results of these studies indicate significant geroprotective and neuroendocrine effects of Epitalone, resulting from its antioxidant, neuro-protective, and antimutagenic effects, originating from both specific and nonspecific mechanisms. Although it has been demonstrated that Epitalon exerts, among other effects, a direct influence on melatonin synthesis, alters the mRNA levels of interleukin-2, modulates the mitogenic activity of murine thymocytes, and enhances the activity of various enzymes, including AChE, BuChE, and telomerase, it remains uncertain whether these are the sole mechanisms of action of this compound. Moreover, despite the considerable volume of research on the biological and pharmacodynamic characteristics of Epitalon, the quantity of physico-chemical and structural investigations of this peptide remains quite limited. This review aims to conclude the most important findings from such studies, thus presenting the current state of knowledge on Epitalon.

The article presents data on the use of peptide bioregulators of cell homeostasis and the protective functions of the body in various dental diseases and pathology of organs and tissues of the maxillofacial region. Issues related to the immunopharmacological effect and clinical use of natural and synthetic peptide thymomimetics (thymalin, thymogen, vilon, epithalamin, cortexin) and peptide bioregulators from cartilaginous (sigumir, chondrolux) and other tissues in case of trauma, as well as inflammatory, inflammatory and other pathological processes of tissues of the oral cavity and maxillofacial region. Particular attention is paid to their use in the complex treatment of dental diseases in the elderly.

It was investigated the influence of polypeptide complex Pineamin on the 6-sulfatoxymelatonin (aMT6S) excretion in urine by ELISA test of 55 elderly patients with diminished melatoninsynthesis pineal gland function. Pineamin in course dose 100 mg has increased night level of aMT6S urine excretion in 1,9 times in comparison with relevant value untreated. Similar effect was obtained early for medical drug Epithalamin. Epithalamin also restored melatonin level in human and animals during aging. Thus, Pineamin and Epithalamin have similar stimulate effect on melatonin synthesis in elderly people pineal gland.

The effects of melatonin and epithalamin on the content of protein and lipid peroxidation products in the cortex and hippocampus of hypoxic rats were studied under conditions of acute hypobaric hypoxia equivalent to the altitude of 12,000 m. Pineal preparations reduced the intensity of free-radical processes in the brain exposed to acute hypoxia. Epithalamin more effectively than exogenous melatonin protected hippocampal neurons during acute hypoxia by reducing free-radical damage to lipids and proteins.

The paper presents the results of randomized comparative study of the efficiency of peptide geroprotector from the pituitary gland in elderly patients with rapidly aging cardiovascular system. Over three years 39 coronary patients received, in addition to basic therapy, regular courses of epithalamin (peptide drug), while 40 coronary patients (control group) received basic therapy alone. Long-term treatment with epithalamin (6 courses over 3 years) decelerated aging of the cardiovascular system, prevented age-associated impairment of physical endurance, normalized circadian rhythm of melatonin production and carbohydrate and lipid metabolism. A significantly lower mortality in the group of patients treated with epithalamin in parallel with basic therapy also indicated a geroprotective effect of the peptide preparation from the pineal gland.

In contrast to young people, changes in the rhythms of parameters manifested in elderly and senile chronic coronary patients in inversion (decreased T cell count in the peripheral blood, values of lymphocyte blastogenesis test with phytohemagglutinin, and phagocytic index in the fall), monotony (B cell count in the peripheral blood), decreased amplitude of serum hydrocortisone, and desynchronization. The levels of thymic serum factor and IgG were higher in the fall than in the spring, but the seasonal difference leveled after 2.5 years of observation. On the other hand, the rhythms of changes in the thymic serum factor and hydrocortisone were retained in patients with chronic coronary disease after 6 courses of epithalamin by the optimal protocol (period of observation 30 months) and blood T cell count increased in the fall. Improvement of the rhythms of the parameters was associated with a benign clinical course of the disease.

It was shown that peptide preparations from the pineal gland (epithalamin and epitalon) possess antioxidant properties exceeding in some cases the effects of the well-known scavenger of reactive oxygen species (ROS), the melatonin, which is also produced by the pineal gland. The methods used in our experiments in old rats included determination of total antioxidant and antiradical activities, as well as those of antioxidant enzymes (superoxide dismutase=SOD, glutathione peroxidase, glutathione-S-transferase, etc.) in blood serum, liver and brain. It has been revealed that epithalamin (polipeptide preparation from bovine brain) and its active fragment, epitalon (Ala-Glu-Asp-Gly) along with their ability to stimulate melatonin production, have an antioxidant mechanism that is quite different from the action of melatonin. Epithalamin can be more beneficial than melatonin because the former not only produces direct antioxidant effects, but also is able to stimulate the expression of SOD, ceruloplasmin and other antioxidant enzymes. The possibility of oxidation chains by their interaction with different ROS by means of binding of transition metals (Fe(2+)) cannot also be excluded. Thus, the results of our experiments testify that the pineal gland peptides enhance the antioxidant defense system, which can contribute to their geroprotective properties.

Circadian rhythm of plasma melatonin concentrations in healthy elderly subjects was studied before and after a course treatment with Epithalamin (peptide preparation from the pineal gland). Epithalamin modulated the melatonin-producing function of the pineal gland. During the dark period plasma melatonin concentration increased in subjects with initially lowered activity of the pineal gland, while in subjects with normal epiphyseal function plasma melatonin concentration tended to decrease.

The effect of epithalamin on circadian rhythms of thymic serum factor titers and melatonin concentrations in the blood of elderly people was studied. Course treatment with epithalamin modulated the rhythm of the thymic endocrine function. The increase in the titer of thymic serum factor at night coincided with the increase in blood melatonin concentration and shift of its acrophase to 3.00, which was characteristic of young people. In elderly people with preserved nocturnal peak of the thymic serum factor titer before therapy the nocturnal (3.00) concentration of melatonin was high and did not change after drug therapy. The correlation between melatonin concentration and titer of thymic serum factor increased after epithalamin treatment.

Researchers of the St. Petersburg Institute of Bioregulation and Gerontology of the North-Western Branch of the Russian Academy of Medical Sciences and the Institute of Gerontology of the Ukrainian Academy of Medical Sciences (Kiev) clinically assessed the geroprotective effects of thymic (Thymalin) and pineal (Epithalamin) peptide bioregulators in 266 elderly and older persons during 6-8 years. The bioregulators were applied for the first 2-3 years of observation.

Researchers of the St. Petersburg Institute of Bioregulation and Gerontology of the North-Western Branch of the Russian Academy of Medical Sciences and the Research Institute of Gerontology of the Ukrainian Academy of Medical Sciences (Kiev) clinically assessed the geroprotective effects of thymic and epiphyseal peptide bioregulators (Thymalin and Epithalamin, correspondingly) in 266 elderly and older persons during 6-8 years (the bioregulators were applied for the first 2-3 years of observation). The obtained results convincingly confirmed the ability of the bioregulators to normalize the basic functions of the human organism, i.e. to improve the indices of the cardiovascular, endocrine, immune, and nervous systems, homeostasis, and metabolism. The restoration of homeostasis in the patients was accompanied by a 2.0-2.4-fold decrease in acute respiratory disease incidence, reduced incidence ischemic heart disease clinical manifestations, hypertension, deforming osteoarthrosis, and osteoporosis, as compared to the control group. Such a significant improvement in the somatic state of the peptide-treated patients corresponded to a decrease in their mortality rate during the observation period: 2.0-2.1-fold among the Thymalin-treated patients, 1.6-1.8-fold--in the Epithalamin-treated group, and 2.5-fold--in the patients treated with Thymalin combined with Epithalamin, as compared to the control group. A separate group of patients was treated with Thymalin combined with Epithalamin annually for 6 years. We registered a 4.1-fold mortality decrease in this group as compared to the control level. The results of our research confirmed the conclusion on the high geroprotective efficacy of Thymalin and Epithalamin and the expediency of their application in medicine and social care as the means of health maintenance and age-related pathology prevention in persons over 60 years old enabling the prolongation of the active period of their lives.

The review on our own data on the effect of the pineal peptide preparation Epithalamin on free radical processes in rodents and humans is presented in this paper.

Immunohistochemical and morphometric analysis showed that epithalamin and epithalon produced similar effects on the functional morphology of the spleen in pinealectomized rats. Both peptides prevented hyperplasia of lymphoid cells in follicular germinative centers induced by pinealectomy and potentiated the decrease in extramedullary hemopoiesis. These findings confirm the data on functional relationships between the pineal gland and immune system. The effects of epithalamin and epithalon on cell and tissue homeostasis in the spleen of old pinealectomized rats can be regarded as a manifestation of the general regulatory effect of these peptides.

Treatment with pineal peptide preparation epithalamin was followed by the increase of the mean lifespan of female D. melanogaster, SHR mice, C3H/Sn mice and LIO rats by 11-31% (P < 0.05). Ninety percent mortality as well as maximum lifespan were increased in fruit flies, C3H/Sn mice and rats. Mortality rate was decreased by 52% in D. melanogaster, by 52% in rats, by 27% in C3H/Sn mice. It did not change in SHR mice exposed to epithalamin. Treatment with the pineal peptide increased MRDT in flies, C3H/Sn mice and rats. It has been shown that epithalamin increased synthesis and secretion of melatonin in rats and inhibits free radical processes in rats and in D. melanogaster. It is suggested that antioxidative properties of epithalamin lead to increased lifespan of three different animal species.

It was shown previously that epithalamin delays age-related changes in reproductive and immune systems and increases the life span of mice and rats. These effects could be mediated by stimulating influences of epithalamin on synthesis and secretion of melatonin and on free radical processes. A comparative study on the effect of epithalamin and melatonin on both the life span of Drosophila melanogaster (strain HEM) and on the intensity of lipid peroxidation and activity of antioxidative enzymes in their tissues was the main aim of this work. Melatonin and epithalamin was added to the nutrition medium (100 micrograms/ml) during 2-3rd age of larvas. For survival analysis the flies were passed (five coupes per vessel) each 3-7 days. Lipid peroxidation was evaluated as the level of ketodienes (KD) and conjugated hydroperoxides (CHP) in fly tissues at the age of 11 days. Activity of Cu, Zn-superoxide dismuatse (SOD) and catalase was evaluated as well. The mean, median and maximum life span (MLS) were estimated. Mortality rate (MR) was calculated as alpha in the Gompertz equation (R = Ro (exp alpha t) and mortality rate doubling time (MRDT) as in 2/alpha. These parameters in groups of male and female flies exposed to melatonin and in male flies exposed to epithalamin were no different from the parameters for controls. However, exposure to epithalamin was followed in females by a significant increase in mean life span (by 17%, P < 0.02), of median (by 26%), of MLS by 14% and by a 2.12 times decrease of MR (P < 0.01) and MRDT (by 32%) compared with female controls. The level of CHP and KD in the tissues of male control flies was 40 and 49% less than that in females and indirectly correlates with male life span. Exposure to melatonin was followed by a decrease in the level of CHP and KD in females and the deletion of sex differences in them. Exposure to epithalamin significantly decreased the level of CHP and KD in female flies compared to controls (2.3 and 3.4 times, respectively, P < 0.001). Exposure to melatonin failed to influence the activity of catalase in males but increased it in females by 24% (P < 0.02) and failed to influence SOD activity both in males and females. Exposure to epithalamin was followed by a significant increase in activity of catalse, 20% in males and 7% in females and by an increase in SOD activity in males (41%). Thus, it was shown that exposure to epithalamin significantly increases the mean life span and MLS of female D.melanogaster and slowed down their aging rate by 2.12 times. This effect is in good agreement with the inhibiting effect of epithalamin in lipid peroxidation processes in fly tissues.

The effect of cortexin and epithalamin on the cell growth rate was investigated in the organotypic tissue culture of dorsal root ganglia (DRG), and of cortex and subcortical structures of 10-11-day old chick embryos. Cortexin in concentrations of 20 and 100 ng/ml is active, inducing a more intensive neurite outgrowth in DRG, compared to the control. Epithalamin was active in concentrations 20 and 200 ng/ml. Cortexin (100 ng/ml) was active in the cortex tissue culture, but inhibited the neurite growth in the subcortical structures culture. The stimulation of this culture to development was evident after using 200 ng/ml epithalamin. The neurite stimulating effect of cortexin and epithalamin is presumably associated with neurotrophic factors.