The short version of Khavinson fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
Discussions in the literature often conflate three distinct entities: the pineal extract epithalamin, the isolated tetrapeptide AEDG, and commercial preparations sold under similar names. Reviews citing older Russian-language studies sometimes omit detail on purity, route of administration and control groups, which makes cross-study comparison difficult. Researchers working with the compound generally note the need for independent replication, standardized enzyme assays, and clearer reporting of peptide identity. These caveats are relevant when weighing claims that appear in secondary sources rather than in primary reports.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
| 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.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
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.
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.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
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.
CH3COCl + 4 HF → CF3COF + 3 H2 + HCl CF3COF + H2O → CF3COOH + HF Wet samples can be dried by addition of trifluoroacetic anhydride. An older route to TFA proceeds via the oxidation of 1,1,1-trifluoro-2,3,3-trichloropropene with potassium permanganate. The trifluorotrichloropropene can be prepared by Swarts fluorination of hexachloropropene.
=== Common === Common side effects include sedation, drooling, constipation, headaches, trembling hands, digestive problems, low blood pressure, dry mouth, nausea, addiction, physical and psychological dependence.
=== Depression === Selegiline has been clinically studied in combination with oral L-phenylalanine or β-phenethylamine in the treatment of depression and was reported to be effective. L-Phenylalanine is known to be metabolized into β-phenethylamine, selegiline is known to strongly inhibit the metabolism of β-phenethylamine, and β-phenethylamine has been implicated in having psychostimulant-like mood-lifting effects.
Hazard research is published: researchers report gas stoves disperse nitrogen dioxide – associated with respiratory conditions such as asthma – at unsafe levels also outside kitchens for hours (3 May), a study reported large amounts of microplastic in brains with concentrations being much larger in samples from 2024 compared to 2016 (6 May), an experimental study finds GPT-4-based large language model-powered conversational search increases selective exposure compared to conventional Web search (11 May), a study indicates fish oil omega-3 supplements, widely taken due to associations of high omega-3 levels and good health or cognition, might be a substantial risk factor for atrial fibrillation and stroke except for those who took these already having atrial fibrillation (21 May), and researchers report continued transmission of bird flu within dairy cattle and show that their raw milk can infect mice (24 May).
Sources: en.wikipedia.org
=== EC 1.2.4 With a disulfide as acceptor === EC 1.2.4.1: pyruvate dehydrogenase (acetyl-transferring) EC 1.2.4.2: oxoglutarate dehydrogenase (succinyl-transferring) EC 1.2.4.3: Now included with EC 1.2.4.4, 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring) EC 1.2.4.4: 3-methyl-2-oxobutanoate dehydrogenase (2-methylpropanoyl-transferring)
== Treatment == Benign fibromas may, but need not, be removed. Removal is usually a brief outpatient procedure or using cryotherapy in which the lesion is deep frozen (-196 degrees Celsius using liquid nitrogen) and thawed for two or more cycles, with full recovery within 3 to 4 weeks. The cryotherapy treatment needs no anesthetics and is painless. Another simple treatment is snip removal after injecting local anesthetic.
== Health == A study in the UK of veterinary records found the Birman to have a life expectancy of 14.39 years based on a sample of 38 cats, higher than the 11.74 average overall. Paltrinieri, Giraldi, Prolo, Scarpa, et al. (2017) found that Birman cats have a high serum concentration of creatinine and symmetric dimethylarginine, but most Birman cats have higher concentrations of creatinine than SDMA. Creatinine is a creatine phosphate and is produced during metabolism of creatine, and is excreted through urination. SDMA is a methylated form of the amino acid arginine and is released during normal catabolisms of body proteins. Levels of creatinine and SDMA are found when Birman cats are tested for chronic kidney disease, for which they are at high risk. Birman cats are also at risk of developing feline infectious peritonitis; a disease that alters the renal function (creatinine levels in blood and urine) in the cats. In a review of over 5,000 cases of urate urolithiasis the Birman was over-represented with an odds ratio of 6.77. Feline audiogenic reflex seizures (FARS), a recently discovered type of epilepsy in cats, is believed to be particularly common in Birman cats.
Chapter 8 of the 1977 Soviet Constitution is titled as the "Soviet Union is a union state". Article 70 stated that the union was founded on the principles of "socialist federalism" as a result of the free self-determination of nations and the voluntary association of equal Soviet Socialist Republics. Article 71 listed all fifteen union republics that united into the Soviet Union. According to Article 76 of the 1977 Soviet Constitution, a union republic was defined as a sovereign Soviet socialist state that had united with other Soviet Republics into the USSR. Article 78 of the Constitution stated that the territory of a union republic may not be altered without its consent. The boundaries between republics may be altered by mutual agreement of the republics concerned, if the rest of the union agreed. Article 81 of the Constitution stated that "the sovereign rights of Union Republics shall be safeguarded by the USSR". In the final decades of its existence, the Soviet Union officially consisted of fifteen Soviet Socialist Republics (SSRs). All of them, with the exception of the Russian SFSR (until 1990), had their own local party chapters of the All-Union Communist Party. In 1944, amendments to the All-Union Constitution allowed for separate branches of the Red Army for each Soviet Republic. They also allowed for Republic-level commissariats for foreign affairs and defense, allowing them to be recognized as de jure independent states in international law.
For example, in tissues and cells, the free radical oxidation of linoleic acid produces racemic mixtures of 13-hydroxy-9Z,11E-octadecadienoic acid, 13-hydroxy-9E,11E-octadecadienoic acid, 9-hydroxy-10E,12-E-octadecadienoic acid (9-EE-HODE), and 11-hydroxy-9Z,12-Z-octadecadienoic acid as well as 4-Hydroxynonenal while singlet oxygen attacks linoleic acid to produce (presumed but not yet proven to be racemic mixtures of) 13-hydroxy-9Z,11E-octadecadienoic acid, 9-hydroxy-10E,12-Z-octadecadienoic acid, 10-hydroxy-8E,12Z-octadecadienoic acid, and 12-hydroxy-9Z-13-E-octadecadienoic (see 13-Hydroxyoctadecadienoic acid and 9-Hydroxyoctadecadienoic acid). Similar attacks on arachidonic acid produce a far larger set of products including various isoprostanes, hydroperoxy- and hydroxy- eicosatetraenoates, and 4-hydroxyalkenals. While many of these products are used as markers of oxidative stress, the products derived from linoleic acid appear far more predominant than arachidonic acid products and therefore easier to identify and quantify in, for example, atheromatous plaques. Certain linoleic acid products have also been proposed to be markers for specific types of oxidative stress. For example, the presence of racemic 9-HODE and 9-EE-HODE mixtures reflects free radical oxidation of linoleic acid whereas the presence of racemic 10-hydroxy-8E,12Z-octadecadienoic acid and 12-hydroxy-9Z-13-E-octadecadienoic acid reflects singlet oxygen attack on linoleic acid.
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.
It is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, often abbreviated AEDG. The molecule is linear and contains no modified residues, so it is fully described by its sequence.