Replicative senescence comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-04-06. Numbers and descriptions here follow the published literature rather than marketing 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.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
== Vorkommen == Epitheliale neuroendokrine Tumoren kommen vor allem im Verdauungstrakt und in der Bauchspeicheldrüse vor. Für neuroendokrine Tumoren im Magen und Darm ist auch die alte Bezeichnung Karzinoid (karzinomähnlicher Tumor) noch sehr verbreitet. Dieser sollte wie auch der Begriff APUDom (amine precursor uptake and decarboxylation) nicht mehr verwendet werden. Das kleinzellige Bronchialkarzinom und das Merkelzell-Karzinom der Haut zählen ebenfalls zu den neuroendokrinen Tumoren. Eng verwandt sind die nervenähnlichen Neuroblastome, Phäochromozytome und Paragangliome. 75 % aller neuroendokrinen Tumoren sind im gastroenteropankreatischen System lokalisiert (Gastroenteropankreatischer Neuroendokriner Tumor – Abk. GEP-NET). Die GEP-Tumoren entwickeln sich aus endokrinen (hormonproduzierenden) Zellen, die überall im Verdauungssystem oder damit zusammenhängenden Stellen des Körpers vorkommen und die Aufgabe haben, bestimmte Stoffe zu produzieren, die den Verdauungsprozess steuern. Von ihren Eigenschaften her besitzen diese Zellen Ähnlichkeiten mit Nervenzellen und von ihrer Funktion her zählen sie zu den inneren Drüsen. Daher werden sie neuroendokrine Zellen genannt.
Die Erstbeschreibung von neuroendokrinen Tumoren geht zurück auf den 1933 verstorbenen Pathologen Otto Lubarsch. Zwanzig Jahre darauf wurde erstmals der Begriff Karzinoid von Siegfried Oberndorfer (Krebsforscher, 1876-1944) genutzt, um die neu entdeckte Form von Tumoren im Verdauungstrakt von den wesentlich aggressiveren Adenokarzinomen abzugrenzen. In den darauffolgenden Jahren konnte der neuroendokrine Ursprung der Tumorzellen erhärtet werden.
== Epidemiologie == Neuroendokrine Tumoren des Magen-Darm-Traktes und der Bauchspeicheldrüse (GEP-NET, für Gastro-Entero-Pankreatische Neuroendokrine Tumoren, früher Karzinoide genannt), treten etwa ein- bis zweimal pro 100.000 Einwohner und Jahr auf. Neuroendokrine Tumoren betreffen vorwiegend Patienten im Alter von 50 bis 70 Jahren; Frauen und Männer etwa gleich häufig. Neben den zufälligen (sporadischen) Erkrankungsfällen gibt es zwei Formen von erblichen multiplen endokrinen Neoplasien.
== Hormonproduktion == Etwa 30–50 % der neuroendokrinen Tumoren produzieren hormonell wirksame Aminabkömmlinge, die auch von normalen neuroendokrinen Zellen hergestellt werden, wie etwa Gastrin aus der Magenschleimhaut, Vasoaktives intestinales Peptid aus dem Zwölffingerdarm, Insulin und Glucagon aus der Bauchspeicheldrüse. Die überschießende Hormonkonzentration dieser sogenannten „funktionell aktiven“ Tumoren kann charakteristische Symptome erzeugen. So verursacht ein Gastrin produzierender neuroendokriner Tumor das Gastrinom und das Zollinger-Ellison-Syndrom (Übersäuerung, Magengeschwüre). VIP-produzierende Tumoren verursachen schwere Durchfälle, Glucagonome erhöhten Blutzucker und Insulinome gefährliche Hypoglykämien. Ein wichtiges Anzeichen für Tumoren des Dünndarms ist das Serotonin-assoziierte Karzinoid-Syndrom (Durchfälle, Bauchkrämpfe, Flushs und Herzschäden).
Sources: de.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.