A practical reference on epithalamin: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-19 and is reviewed periodically as new material appears.
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.
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.
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.
| 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 |
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.
The proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
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.
=== Lupron "flare" === During the initial phase of luteinizing hormone-releasing hormone (LHRH) agonist therapy in male patients, there is a notable phenomenon known as the "flare." This occurs when testosterone levels temporarily surge by approximately 50% within the first 1 to 2 weeks of therapy. This increase is a response to the initial stimulation of luteinizing hormone (LH) by the LHRH agonist, leading to a rise in testosterone levels before they begin to decrease as intended. For individuals receiving LHRH agonists as part of gender-affirming care, this temporary increase in testosterone can be particularly distressing, exacerbating gender dysphoria and discomfort. To manage and mitigate these effects, healthcare providers often prescribe antiandrogens during this phase to help block the unwanted increase in testosterone and alleviate the associated distress.
== Early life and career == Kiggans was born in Tampa, Florida, and graduated from high school in Orlando, Florida. As a high school student, she worked at Walt Disney World. She is an alumna of Boston University. In 1993 and 1994, she taught English in Japan through the JET Programme. She also lived in Japan as a Navy spouse for five years. Kiggans joined the United States Navy in 1993 and was a Navy pilot for ten years, flying H-46 and H-3 helicopters. After serving in the military, Kiggans attended nursing school at Old Dominion University and Vanderbilt University School of Nursing. She is an adult geriatric nurse practitioner at Eastern Virginia Medical School and in private practice.
Soy products such as tofu and tempeh, (which contain the inhibitor "genistein") Agaricus subrufescens mushrooms (contain the inhibitors sodium pyroglutamate and ergosterol) Black raspberry (Rubus occidentalis) extract Lingzhi mushrooms (via inhibition of VEGF and TGF-beta) Trametes versicolor mushrooms (Polysaccharide-K) Maitake mushrooms (via inhibition of VEGF) Phellinus linteus mushrooms (via active substance Interfungins A inhibition of glycation) Green tea (catechins) Liquorice (glycyrrhizic acid) Red wine (resveratrol) Antiangiogenic phytochemicals and medicinal herbs Royal jelly (queen bee acid)
=== Acridine orange === Acridine orange (AO) is a nucleic acid selective fluorescent cationic dye useful for cell cycle determination. It is cell-permeable, and interacts with DNA and RNA by intercalation or electrostatic attractions. When bound to DNA, it is very similar spectrally to fluorescein. Like fluorescein, it is also useful as a non-specific stain for backlighting conventionally stained cells on the surface of a solid sample of tissue (fluorescence backlighted staining).
Sources: en.wikipedia.org
The colonization of Tahiti occurred in a time of rivalry for resources of the Pacific by colonizing European nations including the French and the British. It was also a time of rivalry and fighting between the people of Tahiti and neighbouring islands. It is unclear which is the first European ship to arrive at the island of Tahiti but it is often recognised as being HMS Dolphin captained by British Captain Samuel Wallis on 18 June 1767. He met a welcoming party of Tahitians who traded with him. Cultural differences leading to grave communication errors that resulted in a battle in Matavai Bay between three hundred war canoes and HMS Dolphin which fired on the war canoes with muskets, quarterdeck guns and then cannons. The Tahitian chief Obera (Purea) ordered peace offerings from her people after this battle and Wallis and the Tahitians departed on amicable terms when he left on 27 July 1767. A few months later the French arrived on 2 April 1768 with the ships Boudeuse and Etoile captained by Louis-Antoine de Bougainville.
Maximum temperatures rather than minimum temperatures influence the weight of hatchlings unless the minimum temperature exceeds the tolerance limit. In later hatchlings warmer weather and decreased food availability promotes more rapid development resulting in a smaller body size compared to earlier hatchlings. The heaviest hatchlings come from colder habitats. Increased population density also results in decreased adult size as well as slower development.
=== Reaction === Limulus clotting enzyme uses 2H2O to cleave the Arg18-Gly19 and Arg46-Thr47 linkages in coagulogen, forming coagulin + two peptide products. This process activates coagulin, allowing it to gel and form clots around bacterial invaders. The reaction is hydrolytic and catalyzed by the His-Asp-Ser triad in the active site. The hydroxyl group in serine acts as a nucleophile, attacking the carbonyl carbon in the peptide bond. Histidine’s nitrogen atom accepts the hydrogen from serine’s hydroxyl group to make serine a stronger nucleophile. Aspartic acid forms hydrogen bonds with histidine to make this nitrogen atom more electronegative and therefore more likely to accept the hydrogen. The nucleophilic attack results in the peptide bond breaking, allowing one peptide fragment to be released. A water molecule is then deprotonated by the histidine. The resulting hydroxyl acts as a nucleophile to break the bond between the serine and the carbonyl, releasing the rest of the protein. The process is then repeated at the other peptide bond.
==== Resolving debate over foreign aid ==== Some voices in the administration continued to point in the opposite direction: for example, Under Secretary of State Herbert Hoover Jr. and the new ICA head, John Hollister, who represented more frugal attitudes. Given the lack of consensus, Eisenhower and Congress conducted in 1956 several studies to give foreign aid policy a more solid basis. Mainly delivered in early 1957, the reports included an updated version of the essay by Millikan and Rostow that C.D. Jackson had circulated in 1954. The overall view that emerged was that sustained development assistance would have long-term benefits for the U.S. position in the world and, more specifically, that developing countries needed substantial financial assistance in the form of low-interest loans. Developing countries particularly needed softer financing to invest in public health systems, schools, and economic infrastructure, for which "hard", commercial lending was unsuitable. Personnel changes soon reflected this change in the administration's view: Christian Herter succeeded Herbert Hoover Jr. as Under Secretary of State in February 1957, Robert Anderson succeeded George Humphrey as treasury secretary in July 1957, and James H. Smith Jr. replaced John Hollister as ICA Director in September 1957. Eisenhower summarized the conclusions in his May 21, 1957 message to Congress: "This past year ... Congressional Committees, the Executive Branch and distinguished private citizens have just examined these programs anew. ... I recommend the following legislative actions: ...
=== Targets === Aptamer targets can include small molecules and heavy metal ions, larger ligands such as proteins, and even whole cells. These targets include lysozyme, thrombin, human immunodeficiency virus trans-acting responsive element (HIV TAR), hemin, interferon γ, vascular endothelial growth factor (VEGF), prostate specific antigen (PSA), dopamine, and the non-classical oncogene, heat shock factor 1 (HSF1). Aptamers have been generated against cancer cells, prions, bacteria, and viruses. Viral targets of aptamers include influenza A and B viruses, Respiratory syncytial virus (RSV), SARS coronavirus (SARS-CoV) and SARS-CoV-2. Aptamers may be particularly useful for environmental science proteomics. Antibodies, like other proteins, are more difficult to sequence than nucleic acids. They are also costly to maintain and produce, and are at constant risk of contamination, as they are produced via cell culture or are harvested from animal serum. For this reason, researchers interested in little-studied proteins and species may find that companies will not produce, maintain, or adequately validate the quality of antibodies against their target of interest. By contrast, aptamers are simple to sequence and cost nothing to maintain, as their exact structure can be stored digitally and synthesized on demand. This may make them more economically feasible as research tools for underfunded biological research subjects. Aptamers exist for plant compounds, such as theophylline (found in tea) and abscisic acid (a plant immune hormone).
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.
It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.