epithalamin 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.
Last reviewed on 2026-06-07. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.
No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
| 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 |
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.
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
== Further reading == Agulhon, Maurice. The Republican Experiment, 1848–1852 (The Cambridge History of Modern France) (1983) excerpt and text search Amann, Peter H. "Writings on the Second French Republic." Journal of Modern History 34.4 (1962): 409–429. Clark, Christopher (2023). Revolutionary Spring: Fighting for a New World 1848–1849. Penguin Random House. Furet, François. Revolutionary France 1770–1880 (1995), pp 385–437. survey of political history by leading scholar Guyver, Christopher, The Second French Republic 1848–1852: A Political Reinterpretation, New York: Palgrave, 2016 Price, Roger, ed. Revolution and reaction: 1848 and the Second French Republic (Taylor & Francis, 1975). Price, Roger. The French Second Republic: A Social History (Cornell UP, 1972).
== Description == The Wound Man illustrates various injuries that a person might receive through war, accident, or disease: cuts and bruises from multiple weapons, rashes and pustules, thorn scratches, and the bites of venomous animals. The figure also includes some schematic anatomical outlines of several organs within his unusual, transparent abdomen.
Semen, also known as seminal fluid, is a bodily fluid that contains spermatozoa from the male gonads of animals. In humans and placental mammals, seminal fluid is ejaculated through the penis via the urethra. This fluid contains proteolytic and other enzymes as well as fructose, which together promote the survival of spermatozoa and provide a medium through which they can move (or "swim") from the vagina into the uterus and to the fallopian tubes, where they can fertilize the female ovum and form a zygote (diploid cell). Semen is collected from animals for artificial insemination or cryoconservation of genetic material. Cryoconservation of animal genetic resources is a practice that calls for the collection of semen in efforts for conservation of a particular breed.
is the water content of blood, approximately 0.825 w/v for men and 0.838 w/v for women. These calculations assume Widmark's zero-order model for the effects of metabolization, and assume that TBW is almost exactly the volume of distribution of ethanol. Using a more complex model that accounts for non-linear metabolism, Norberg found that Vd was only 84-87% of TBW. This finding was not reproduced in a newer study which found volumes of distribution similar to those in the literature.
Sources: en.wikipedia.org
Through investigation of the surface roughness, the true contact area between friction partners is found to be less than the apparent contact area. Such understanding also drastically changed the direction of undertakings in tribology. The works of Bowden and Tabor yielded several theories in contact mechanics of rough surfaces. The contributions of J. F. Archard (1957) must also be mentioned in discussion of pioneering works in this field. Archard concluded that, even for rough elastic surfaces, the contact area is approximately proportional to the normal force. Further important insights along these lines were provided by James A. Greenwood and J. B. P. Williamson (1966), A. W. Bush (1975), and Bo N. J. Persson (2002). The main findings of these works were that the true contact surface in rough materials is generally proportional to the normal force, while the parameters of individual micro-contacts (pressure and size of the micro-contact) are only weakly dependent upon the load.
Albany is in the central part of Oregon's most populated region, the Willamette Valley. The city rests along the confluence of the Calapooia and Willamette rivers, and although most of Albany falls within Linn County, a smaller portion of the city rests to the north of its downtown on the west bank of the Willamette River in Benton County. According to the United States Census Bureau, the city has a total area of 17.75 square miles (45.97 km2), of which 17.54 square miles (45.43 km2) is land and 0.21 square miles (0.54 km2) is water. Albany has 21.7 square miles (56 km2) within its urban growth boundary. Throughout the city limits and urban growth area, there are limited hills; the city is one of the lowest points along the Willamette Valley, with elevations ranging 180 to 430 feet (55 to 131 m) above sea level. The North Albany district has the most variable elevation, while the downtown and southern end of town have little elevation change throughout.
Nickel is obtained through extractive metallurgy: it is extracted from ore by conventional roasting and reduction processes that yield metal of greater than 75% purity. In many stainless steel applications, 75% pure nickel can be used without further purification, depending on impurities. Traditionally, most sulfide ores are processed using pyrometallurgical techniques to produce a matte for further refining. Hydrometallurgical techniques are also used. Most sulfide deposits have traditionally been processed by concentration through a froth flotation process followed by pyrometallurgical extraction. The nickel matte is further processed with the Sherritt-Gordon process. First, copper is removed by adding hydrogen sulfide, leaving a concentrate of cobalt and nickel. Then, solvent extraction is used to separate the cobalt and nickel, with the final nickel content greater than 86%. A second common refining process is leaching the metal matte into a nickel salt solution, followed by electrowinning the nickel from solution by plating it onto a cathode as electrolytic nickel.
=== Scotland to England in 1984 === He began at the age of 18 at John o' Groats (at the northern tip of Scotland) in 1984, and walked to Land's End in England. On this journey, which he carried out with three other people, he pushed a wheelchair 1,000 miles (1,600 km) and raised £3,500 for The Forelands School for handicapped children. In 1983, he had already run 21 miles (34 km) around a 400-metre track to raise further money for The Forelands School for handicapped children, at Broadstairs in Kent.
== Ion exchange resins == Ion exchange resins are the physical medium that facilitates ion exchange reactions. The resin is composed of cross-linked organic polymers, typically polystyrene matrix and functional groups where the ion exchange process takes place.
Sources: en.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.
Small studies with human participants have been reported, chiefly in Russian-language journals, but they are limited in size and design. No large randomised controlled trial with published results is available.