A practical reference on tetrapeptide: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-09-06. Anything still debated is marked as such rather than presented as settled.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
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.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
Epitalon is a synthetic tetrapeptide whose sequence is alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. It was developed in Russia during the 1980s and 1990s by investigators associated with the St. Petersburg Institute of Bioregulation and Gerontology, who studied short peptides as regulators of gene expression and tissue function. The alternative spelling epithalon appears interchangeably in the literature, and the two names refer to the same molecule. Outside Russia it is encountered chiefly as a research chemical rather than a licensed medicine, and it holds no approval from the United States Food and Drug Administration or the European Medicines Agency.
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.
=== Hertha BSC === The company took a 64.7% stake in Hertha BSC of the German Bundesliga in March 2023, after its sale by Lars Windhorst, who had been majority shareholder since 2019. Due to German football's 50+1 rule, 777 does not control the club. The company faced protests from Hertha's fans. In May 2024, The Athletic reported that fans were less antagonistic toward 777 at Hertha Berlin than at other clubs in their portfolio, partly due to the controversies and low points of Windhorst's ownership.
In commenting on humanity's evolution from an ancient primate ancestor, Jung wrote: "We keep forgetting that we are primates and that we have to make allowances for these primitive layers in our psyche." Jung also developed the notion of different evolutionary layers in the psyche in his discussion of fossil hominins such as Pithecanthropus (Homo erectus). As he writes:
D-xylose reductase (EC 1.1.1.307, XylR, XyrA, msXR, dsXR, monospecific xylose reductase, dual specific xylose reductase, NAD(P)H-dependent xylose reductase, xylose reductase) is an enzyme with systematic name xylitol:NAD(P)+ oxidoreductase. This enzyme catalyses the following chemical reaction
Sources: en.wikipedia.org
== History == The organization's roots traces back to the 19th century with the foundation of the British Indian Army, a Public Works Department was established in the mid-1850s to oversee engineering and construction works while under the control of the Military Board and manned by personnel from the Engineering Corps. It had three branches, Military Works Branch and Civil Works Branch. In 1899, the organization was renamed as Military Works Services and placed under direct command of the Director General Military Works (DGMW). It was finally termed to its current name in 1923. By this time, the organization of the Engineer-in-Chief for British India was based on the workload of the MES. It was divided into four regional commands:-
51 articles on history of Chinese medicine; called "impressive and essential" for latest scholarship and trustworthy bibliographic sources. "(Review) H-Sci-Med-Tech, July 2023. McGrew, Roderick. Encyclopedia of Medical History (1985), brief history on pp. 56–59 Needham J (2000). Sivin N (ed.). Part VI: Medicine. Science and Civilisation in China. Vol. 6, Biology and Biological Technology. Cambridge University Press. ISBN 978-0-521-63262-1. OCLC 163502797. Palmer, James (13 June 2013), "Do Some Harm", Aeon Raphals, Lisa (Winter 2020), "Chinese Philosophy and Chinese Medicine", in Zalta, Edward N. (ed.), The Stanford Encyclopedia of Philosophy, Metaphysics Research Lab, Stanford University Shelton, Tamara Venit (2019). Herbs and Roots: A History of Chinese Doctors in the American Medical Marketplace. New Haven: Yale University Press. ISBN 978-0-300-24940-8. Unschuld, Paul (1986). Nan-Ching: The Classic of Difficult Issues. Berkeley: University of California Press. ISBN 978-0-520-05372-4. —— (1986a). Medicine in China: A History of Pharmaceutics. Berkeley: University of California Press. ISBN 978-0-520-05025-9. —— (2000). Medicine in China: Historical Artifacts and Images. Munich: Prestel. ISBN 978-3-7913-2149-3. —— (2018). Traditional Chinese Medicine: Heritage and Adaptation [Traditionelle chinesische Medizin (2013)]. Translated by Bridie J. Andrews. New York: Columbia University Press. ISBN 978-0-231-17500-5.
== Nomenclature == This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with 2-oxoglutarate as one donor, and incorporation of one atom o oxygen into each donor. The systematic name of this enzyme class is peptide-L-aspartate,2-oxoglutarate:oxygen oxidoreductase (3-hydroxylating). Other names in common use include aspartate beta-hydroxylase, and aspartylpeptide beta-dioxygenase.
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
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.