lyophilised powder 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 2026-02-27. Where a claim depends on a specific study, the study is described rather than over-claimed.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
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.
Interest in epitalon is usually discussed within the broader field of short peptide bioregulators, a category that includes other synthetic di-, tri-, and tetrapeptides studied by the same research group. These compounds share a common rationale: that small fragments of tissue-derived proteins can retain biological activity and can be produced reproducibly. The category as a whole remains outside mainstream pharmacological consensus, and epitalon specifically has a limited presence in independent, non-Russian research literature, which shapes how its evidence base is described.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Synthetic tetrapeptide, four residues |
| Nominal mass | Approximately 390 Da | Free peptide; salt forms differ |
| Appearance | White to off-white powder | Commonly supplied lyophilised |
| Solubility class | Freely soluble in water | Also dissolves in aqueous buffer |
| Typical storage | −20 °C, desiccated | Cold packs used during transport |
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
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.
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.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
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Sources: en.wikipedia.org
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Sources: en.wikipedia.org
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Hitchens supported Ralph Nader in the 2000 US presidential election. He elaborated on his support for Nader in a discussion with Eric Alterman on Bloggingheads.tv, indicating that he was disenchanted with the candidacy of both George W. Bush and Al Gore. Prior to the September 11 attacks in 2001, and the invasion of Iraq and Afghanistan, Hitchens was critical of President George W. Bush's "non-interventionist" foreign policy. He also criticised Bush's support for intelligent design and capital punishment. Hitchens defended Bush's post-11 September foreign policy, but he also criticised the actions of US troops in Abu Ghraib and Haditha, and the US government's use of waterboarding, which, after voluntarily undergoing it, he argued was definitely torture. After Dick Cheney chief of staff Scooter Libby was found guilty of obstruction of justice and perjury, Hitchens defended Libby and called on Bush to pardon him. Hitchens supported George W. Bush in the 2004 US presidential election. He made a brief return to The Nation just before the election and wrote that he was "slightly" for Bush; shortly afterwards, Slate polled its staff on their positions on the candidates and mistakenly printed Hitchens' vote as pro-John Kerry. Hitchens shifted his opinion to "neutral", saying: "It's absurd for liberals to talk as if Kristallnacht is impending with Bush, and it's unwise and indecent for Republicans to equate Kerry with capitulation. There's no one to whom he can surrender, is there? I think that the nature of the jihadist enemy will decide things in the end".
== History == BRT Laboratories, Inc., with its parent company Baltimore RH Typing Laboratory, has been a provider of products and services to the medical, research, and commercial communities since 1945. In April 2000, BRT Laboratories, Inc. was established as an independent and wholly owned subsidiary of Baltimore Rh Typing Laboratory, Inc., for the purpose of continuing commercial testing and service activities.
==== Amide formation pathway ==== The formation of an amide using a carbodiimide is a common reaction, but carries the risk of several side reactions. The acid 1 will react with the carbodiimide to produce the key intermediate: the O-acylisourea 2, which can be viewed as a carboxylic ester with an activated leaving group. The O-acylisourea will react with amines to give the desired amide 3 and urea 4. The possible reactions of the O-acylisourea 2 produce both desired and undesired products. The O-acylisourea 2 can react with an additional carboxylic acid 1 to give an acid anhydride 5, which can react further to give the amide 3. The main undesired reaction pathway involves the rearrangement of the O-acylisourea 2 to the stable N-acylurea 6. The use of solvents with low dielectric constants such as dichloromethane or chloroform can minimize this side reaction.
Sources: en.wikipedia.org
No. Epithalamin is a heterogeneous peptide fraction obtained from pineal gland extract and contains many components. Epitalon is a single synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly. Researchers synthesised the shorter peptide while attempting to identify active sequences within the extract.
No endogenous peptide with this exact sequence has been described as a circulating hormone or signalling molecule. The tetrapeptide was designed as a synthetic analogue based on fragments observed in pineal preparations. Any activity discussed in the literature therefore refers to administered material rather than to a natural pool of the compound.
It is not an approved medicine in major jurisdictions and does not appear in the major pharmacopoeias. Material is usually distributed as a research chemical or laboratory reagent. Such labelling places handling responsibility on the purchaser and does not indicate that a regulatory body has reviewed the substance.
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.