epitalon is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-05-16. Numbers and descriptions here follow the published literature rather than marketing material.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Ala-Glu-Asp-Gly | Often abbreviated AEDG in research literature |
| Common synonyms | Epithalon, epitalon, AEDG | Spelling variants refer to the same tetrapeptide |
| Molecular formula | C14H22N4O9 | Theoretical monoisotopic mass near 390.35 Da |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility class | Freely soluble in water | Hydrophilic peptide; dissolves in aqueous buffer |
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
Discussions in the literature often conflate three distinct entities: the pineal extract epithalamin, the isolated tetrapeptide AEDG, and commercial preparations sold under similar names. Reviews citing older Russian-language studies sometimes omit detail on purity, route of administration and control groups, which makes cross-study comparison difficult. Researchers working with the compound generally note the need for independent replication, standardized enzyme assays, and clearer reporting of peptide identity. These caveats are relevant when weighing claims that appear in secondary sources rather than in primary reports.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
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.
A large body of evidence shows either directly or indirectly that small ions (from small molecules) are liberated into the gas phase through the ion evaporation mechanism, while larger ions (from folded proteins for instance) form by charged residue mechanism. A third model invoking combined charged residue-field emission has been proposed. Another model called chain ejection model (CEM) is proposed for disordered polymers (unfolded proteins). The ions observed by mass spectrometry may be quasimolecular ions created by the addition of a hydrogen cation and denoted [M + H]+, or of another cation such as sodium ion, [M + Na]+, or the removal of a hydrogen nucleus, [M − H]−. Multiply charged ions such as [M + nH]n+ are often observed. For large macromolecules, there can be many charge states, resulting in a characteristic charge state envelope. All these are even-electron ion species: electrons (alone) are not added or removed, unlike in some other ionization sources. The analytes are sometimes involved in electrochemical processes, leading to shifts of the corresponding peaks in the mass spectrum. This effect is demonstrated in the direct ionization of noble metals such as copper, silver and gold using electrospray. The efficiency of generating the gas phase ions for small molecules in ESI varies depending on the compound structure, the solvent used and instrumental parameters. The differences in ionization efficiency reach more than 1 million times.
== Stimulus == How the secretion of motilin is regulated is largely unknown, although some studies suggest that an alkaline pH in the duodenum stimulates its release. However, at low pH it inhibits gastric motor activity, whereas at high pH it has a stimulatory effect. Some studies in dogs have shown that motilin is released during fasting or interdigestive period, and intake of food during this period can prevent the secretion of motilin. Intravenous injection of glucose, which increases the release of insulin, is also found to inhibit cyclic elevation of plasma motilin. Other studies on dogs have also suggested that motilin acted as endogenous ligand in positive feedback mechanism to stimulate the release of more motilin. In dogs and cats, motilin secretion is stimulated by hydrogen ions (protons) and lipids when the animal is in a "fed" state. However, during fasting, motilin is periodically released into the serum to initiate phase III of the migrating motor complex.
hit identification using virtual screening (structure- or ligand-based design) hit-to-lead optimization of affinity and selectivity (structure-based design, QSAR, etc.) lead optimization of other pharmaceutical properties while maintaining affinity
Photoanomerization with UV light allows for inversion about the 1' anomeric centre to give the correct beta stereochemistry; one problem with this chemistry is the selective phosphorylation of alpha-cytidine at the 2' position. However, in 2009, they showed that the same simple building blocks allow access, via phosphate controlled nucleobase elaboration, to 2',3'-cyclic pyrimidine nucleotides directly, which are known to be able to polymerise into RNA. Organic chemist Donna Blackmond described this finding as "strong evidence" in favour of the RNA world. However, John Sutherland said that while his team's work suggests that nucleic acids played an early and central role in the origin of life, it did not necessarily support the RNA world hypothesis in the strict sense, which he described as a "restrictive, hypothetical arrangement". The Sutherland group's 2009 paper also highlighted the possibility for the photo-sanitization of the pyrimidine-2',3'-cyclic phosphates. A potential weakness of these routes is the generation of enantioenriched glyceraldehyde, or its 3-phosphate derivative (glyceraldehyde prefers to exist as its keto tautomer dihydroxyacetone). On August 8, 2011, a report, based on NASA studies with meteorites found on Earth, was published suggesting building blocks of RNA (adenine, guanine, and related organic molecules) may have been formed in outer space.
Initial letters are used where there is no ambiguity: C cysteine, H histidine, I isoleucine, M methionine, S serine, V valine. No other amino acids in this set begin with each of those letters. Where arbitrary assignment is needed, the structurally simpler amino acids are given precedence: A alanine, G glycine, L leucine, P proline, T threonine. For example, alanine is simpler than arginine or asparagine, the other amino acids starting with "a". F PHenylalanine and R aRginine are assigned by being phonetically suggestive, W tryptophan is assigned based on the double ring being visually suggestive to the bulky letter W, K lysine and Y tyrosine are assigned as alphabetically nearest to their initials L and T (note that U was avoided for its similarity with V, while X was reserved for undetermined or atypical amino acids); for tyrosine the mnemonic tYrosine was also proposed, D aspartate was assigned arbitrarily, with the proposed mnemonic asparDic acid; E glutamate was assigned in alphabetical sequence being larger by merely one methylene –CH2– group, N asparagine was assigned arbitrarily, with the proposed mnemonic asparagiNe; Q glutamine was assigned in alphabetical sequence of those still available (note again that O was avoided due to similarity with D), with the proposed mnemonic Qlutamine.
Sources: en.wikipedia.org
Examining the structure and function of the cornea at the molecular level, Investigating corneal cell biology, and Translational research initiatives dedicated to improving laser refractive surgery techniques that can help address certain complications that can arise following these procedures. Hafezi is considered to be a leading expert and key opinion leader in the development and translation of CXL and its multiple applications in the field of ophthalmology, including the treatment of corneal ectatic disorders like keratoconus, pellucid marginal degeneration and post-LASIK ectasia. Hafezi and his colleagues have also pioneered the use of CXL for the treatment of corneal infections, calling the technique "photoactivated chromophore for infectious keratitis cross-linking", or PACK-CXL. Hafezi has published almost 200 articles in various peer-reviewed scientific journals since 1993, including Nature Medicine, Nature Genetics, Investigative Ophthalmology & Visual Science (IOVS), the Journal of Refractive Surgery, and Cell Death & Differentiation. His work in the field of corneal collagen cross-linking has led him to receive a number of international awards. In 2014, 2016, 2018, 2020, 2023, 2025, and 2026 his peers ranked Hafezi as one of the top 100 most influential people in ophthalmology.
Indium is a shiny silvery-white, highly ductile post-transition metal with a bright luster. It is so soft (Mohs hardness 1.2) that it can be cut with a knife or be bitten into by human teeth. Indium also leaves a visible line like a pencil when rubbed on paper. It is a member of group 13 on the periodic table and its properties are mostly intermediate between its vertical neighbors gallium and thallium. As with tin, a high-pitched cry is heard when indium is bent – a crackling sound due to crystal twinning. Like gallium, indium is able to wet glass and has a low melting point, 156.60 °C (313.88 °F); higher than its lighter homologue, gallium, but lower than its heavier homologue, thallium, and lower than tin.< The boiling point is 2072 °C (3762 °F), higher than that of thallium, but lower than gallium, conversely to the general trend of melting points, but similarly to the trends down the other post-transition metal groups because of the weakness of the metallic bonding with few electrons delocalized. The density of indium, 7.31 g/cm3, is also greater than gallium, but lower than thallium. Below the critical temperature, 3.41 K, indium becomes a superconductor. Indium crystallizes in the body-centered tetragonal crystal system in the space group I4/mmm (lattice parameters: a = 325 pm, c = 495 pm): this is a slightly distorted face-centered cubic structure, where each indium atom has four neighbours at 324 pm distance and eight neighbours slightly further (336 pm).
This local processing is especially important in image processing, where the early CNN layers typically identify simple local patterns such as edges and curves, with subsequent layers detecting more complex patterns like textures, and eventually whole objects.
(2026) reconstruct the evolutionary history of members of the genus Arvicola in Western Europe during the late Middle and Late Pleistocene on the basis of the study of morphology of teeth from the Lazaret Cave and Moula-Guercy sites (France), Abauntz Cave, Cova Eirós (Spain) and Trou Al'Wesse (Belgium), interpreted as consistent with a complex biogeographic history including multiple dispersals into Western Europe and subsequent local extinctions and recolonizations. New fossil material of members of the genus Byzantinia, providing new information on the morphology of teeth of members of this genus and their evolution, is described from the Miocene strata of the Zahleh Formation (Lebanon) by López-Antoñanzas et al. (2026). A study on the phylogenetic relationships and evolutionary history of extant and extinct hamsters is published by Dirnberger et al. (2026). Bujalska et al. (2026) reconstruct the evolutionary history of European small hamsters on the basis of mitochondrial genomes from Late Pleistocene and Holocene remains from Central and Western Europe, the Balkans and Anatolia, identifying evidence of presence of the winter white dwarf hamster in Central Europe during the Late Pleistocene. Pacheco-Castro, Carranza-Castañeda & Wang (2026) report the discovery of fossil material of Sigmodon minor from the Pliocene strata of the San Miguel de Allende Basin, representing the first record of the species from central Mexico and its southernmost known record in North America.
Sources: en.wikipedia.org
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine–glutamate–aspartate–glycine, also written AEDG. It was developed in Russian gerontology research and is studied for proposed effects on telomerase, melatonin regulation, and neuroendocrine function. It is not an approved pharmaceutical in the United States or the European Union.
No. Epithalamin is a peptide-rich extract prepared from bovine pineal glands, while epitalon is a short synthetic peptide designed as a defined analogue of it. The synthetic version was intended to provide a reproducible molecule with some of the same proposed biological activity.
Telomere elongation and telomerase activation have been reported in cultured human somatic cells, but evidence from living human subjects is limited and has not been independently confirmed at scale. Reported findings come largely from small studies with differing designs, so the question remains open rather than settled.
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.