A practical reference on Epithalamin: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-02-14. Anything still debated is marked as such rather than presented as settled.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. It was designed at the St. Petersburg Institute of Bioregulation and Gerontology as a short, chemically defined analogue of epithalamin, a fraction obtained from bovine pineal tissue. Small peptide bioregulators of this type formed a long-running line of work there from the 1980s onward. Because the molecule is produced by solid-phase synthesis rather than extraction, its composition is exact and its purity can be measured directly.
The most frequently cited proposed action is induction of telomerase, the enzyme that adds repeat sequences to chromosome ends. Cell-culture work from the originating group reported higher telomerase reverse transcriptase expression and measurable telomere elongation in human somatic cells after exposure. How a four-residue peptide would reach nuclear gene regulation is not established, and no cell-surface receptor or uptake route has been identified. Additional reports describe changes in melatonin secretion, antioxidant enzyme activity and lipid peroxidation in aged animals, but these findings remain mechanistically unconnected to the telomerase observation.
Published evidence comes mainly from Russian-language journals and from a single research group, with small sample sizes and limited independent replication. A few laboratories outside that group have examined related peptides and reported weaker or absent telomerase effects, so the central claim is best described as contested rather than settled. Rodent studies report modest changes in some ageing markers and in survival, but designs vary and control conditions are often sparse. No large randomised trial in humans has been published, and long-term safety data in healthy populations are correspondingly thin.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Calculated from the four residues with three water losses |
| Molecular mass | About 390.35 g/mol | Monoisotopic mass near 390.14, used for mass-spectrometric identification |
| Peptide sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG; no disulfide bonds or modified residues |
| Appearance | White to off-white solid | Supplied as a dried powder |
| Isoelectric point | Around 4 | Estimated from aspartate and glutamate side-chain pKa values |
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
Unlike other ribosomal peptide natural products, which are normally synthesized with a leader peptide that is cleaved, bottromycin is synthesized with a follower peptide. The presence of a follower peptide was identified by bioinformatic analysis of the bottromycin biosynthetic cluster.
It has been proposed that high intrinsic activity at 5-HT1A postsynaptic receptors is necessary for maximal therapeutic benefits to come to prominence, and as a result, investigation has commenced in azapirones which act as 5-HT1A receptor full agonists such as alnespirone and eptapirone. Indeed, in preclinical studies, eptapirone produces robust antidepressant effects which surpass those of even high doses of imipramine and paroxetine.
=== Fertilizer === Hydrolyzing a protein improves the digestibility not only for animals, but also for soil microbes. As a result, it becomes useful as a fertilizer providing nitrogen and potentially also sulfur. Hydrolyzed keratin from chicken feather is the most common type, though other kinds of waste proteins (e.g. waste wool, waste fish) are also re-used this way. Hydrolyzed protein fertilizer is considered an organic fertilizer. It contains a high amount of available nitrogen, and unlike unhydrolyzed feather meal, tends to release the nitrogen quickly. It helps the growth of soil microbes and improves soil quality.
=== Psychological theories === The psychoanalytic theory model defines addiction as a form of defense against feelings of hopelessness and helplessness as well as a symptom of failure to regulate powerful emotions related to adverse childhood experiences (ACEs), various forms of maltreatment and dysfunction experienced in childhood. In this case, the addictive substance provides brief but total relief and positive feelings of control. Psychological contributions include learning and conditioning processes, impulsivity, reward sensitivity, and the use of substances to cope with negative mood or trauma. Conditioning models hold that environmental cues can acquire motivational significance of their own and trigger craving and relapse even after long periods of abstinence. Reviews of alcohol use disorder identify overvaluation of the drug's reinforcing effects, elevated impulsivity across several dimensions, the acute effects of stress and environmental triggers, and a lack of alternative rewarding activities as well-established psychological determinants, and present these processes as interacting with biological and social vulnerabilities, each reinforcing the others.
Sources: en.wikipedia.org
== Reaction similarity == Similarity between enzymatic reactions (EC) can be calculated by using bond changes, reaction centres or substructure metrics (EC-BLAST Archived 30 May 2019 at the Wayback Machine).
In addition, legal counsel to the president Harriet Miers and deputy chief of staff to the president Joshua Bolten were both found in contempt of Congress. In 2010, the Justice Department investigator concluded that though political considerations did play a part in as many as four of the attorney firings, the firings were "inappropriately political" but not criminal. According to the prosecutors, there was insufficient evidence to pursue prosecution for any criminal offense.
=== "Central Dogma" === Watson and Crick's model attracted great interest immediately upon its presentation. Arriving at their conclusion on February 21, 1953, Watson and Crick made their first announcement on February 28. In an influential presentation in 1957, Crick laid out the "central dogma of molecular biology", which foretold the relationship between DNA, RNA, and proteins, and articulated the "sequence hypothesis." A critical confirmation of the replication mechanism that was implied by the double-helical structure followed in 1958 in the form of the Meselson–Stahl experiment. Messenger RNA (mRNA) was identified as an intermediate between DNA sequences and protein synthesis by Brenner, Meselson, and Jacob in 1961. Then, work by Crick and coworkers showed that the genetic code was based on non-overlapping triplets of bases, called codons, and Har Gobind Khorana and others deciphered the genetic code not long afterward (1966). These findings represent the birth of molecular biology.
All lipids can experience some sort of positive or negative alternating or spontaneous curvature due to variations in sizes between the hydrophobic and the hydrophilic region. Temperature changes can also lead to changes in the biomembrane.
== Biochemical structure == It is a low-molecular-weight neurotoxin which has highly functional polar groups: free phenolic OH and amine and guanidine residues. It also possesses arginine (free NH2) connected to a -NH (CH)3 NH (C ~) 3NH (CH) 5-NH- one through a peptide bond polyamine. The polyamine is connected to the asparagine's α-carboxyl group. The amino group of this aminoacid is linked to 2,4-dihydroxyphenyl acetic acid. Its structure was established using spectroscopy 1H, 13C-RMN, mass spectrometry, and elemental aminoacid analysis. A complete synthesis strategy of argiotoxin and derivatives was developed in order to make biological tests in different living beings. A noted type of argiotoxin, the Arg-636, which molecular formula is C29H52N10O6 [3], has a molecular weight of 636.78658 g/mol. It has a formal charge of 0. Its IUPAC name is: (2S) - N- { 5 - [ 3 - ( 3 - [ [ (2S)-2-amino-5-(diaminomethylideneamino) pentanoyl ] amino ] propylamino ) propylamino ] pentyl } -2- { [ 2 - (2,4-dihydroxyphenyl) acetyl ] amino } butanediamide
Sources: en.wikipedia.org
No. Epithalamin is a peptide-containing extract of bovine pineal glands, while epitalon is a single synthetic tetrapeptide. The extract contains many peptides and other tissue components, so its composition varies between batches in ways that a synthesised sequence does not.
It is not recognised as an endogenous peptide hormone. The four-residue sequence can appear inside larger proteins and in digestive fragments of dietary protein, but no dedicated pathway producing it as a signalling molecule has been identified.
Several cell-culture reports describe increased telomerase activity after treatment, measured by enzyme assays or by transcript levels. Results differ between cell types and laboratories, and measured telomere lengthening has been reported in some studies but not in others, which leaves the physiological relevance open.
No. Epithalamin is a heterogeneous peptide fraction obtained from pineal gland extract and contains many components. Epitalon is a single synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly. Researchers synthesised the shorter peptide while attempting to identify active sequences within the extract.