tetrapeptide 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.
Updated 2025-08-29. Numbers and descriptions here follow the published literature rather than marketing material.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
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.
（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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
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.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Ala-Glu-Asp-Gly | Often abbreviated AEDG in research literature |
| Common synonyms | Epithalon, epitalon, AEDG | Spelling variants refer to the same tetrapeptide |
| Molecular formula | C14H22N4O9 | Theoretical monoisotopic mass near 390.35 Da |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility class | Freely soluble in water | Hydrophilic peptide; dissolves in aqueous buffer |
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.
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.
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.
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.
Relamorelin (INN, USAN) (developmental code names RM-131, BIM-28131, BIM-28163) is a synthetic peptide, centrally penetrant, selective agonist of the ghrelin/growth hormone secretagogue receptor (GHSR) which is under development by Allergan pharmaceuticals for the treatment of diabetic gastroparesis, chronic idiopathic constipation, and anorexia nervosa. It is a pentapeptide and an analogue of ghrelin with improved potency and pharmacokinetics. In humans, relamorelin produces increases in plasma growth hormone, prolactin, and cortisol levels, and, like other GHSR agonists, increases appetite. As of June 2015, relamorelin is in phase II clinical trials for diabetic gastroparesis and constipation. The United States Food and Drug Administration (FDA) has granted Fast Track designation to relamorelin for diabetic gastroparesis. The development of the drug is uncertain as the most recent mention of it was in a 2019 SEC filing from the drug manufacturer lists the drug's expected launch year as 2024, but not in subsequent filings or press releases.
Milk production can be induced in transgender women by the use of hormone medication, usually a galactagogue similarly to induced lactation in cisgender women, with domperidone being a common choice. Induced lactation without the use of galactagogues has also been demonstrated in at least two cases using a modified feminizing hormone therapy featuring progesterone and nipple stimulation, with eventual successful production of breast milk. In one case report, a transgender woman was able to produce 7 mL of milk per day with hormone treatment. A different transgender woman was able to produce 8 oz of milk per day achieving "sufficient breast milk volume to be the sole source of nourishment for her child for six weeks." Several studies analyzing milk samples from trans women have found them to contain nutrients within parameters suitable for nursing. A 2018 survey of medical professionals with attending a WPATH event where 34% of the surveyed professionals had met a transgender patient expressing interest in induced lactation, 21% of them knew of providers who facilitated lactation for transgender patients, and 9% had themselves helped trans women induce lactation.
== Adverse effects == The US Food and Drug Administration (FDA) prescribing information for taletrectinib includes warnings and precautions for hepatotoxicity, interstitial lung disease/pneumonitis, QTc interval prolongation, hyperuricemia, myalgia with creatine phosphokinase elevation, skeletal fractures, and embryo-fetal toxicity.
She wore an imported black satin dress heavily beaded with tiny black jet beads, black satin slippers, beaded, and had on her rarely beautiful diamonds. ... She stood before us, seemingly slight, graceful of carriage, and exquisitely beautiful even to critical eyes. Then, still standing, she faced her class as one who knew herself to be a teacher by divine right. She turned to the student at the end of the first row of seats and took direct mental cognizance of this one, plainly knocked at the door of this individual consciousness. ... This continued until each member of the class had received the same mental cognizance. No audible word voiced the purely mental contact. It was in part because of her unusual personality that Christian Science flourished, despite the numerous disputes she initiated among her followers. "She was like a patch of colour in those gray communities," McClure's wrote, "She never laid aside her regal air; never entered a room or left it like other people." Mark Twain, a prominent critic of hers, described her in 1907 as "vain, untruthful [and] jealous", but "[i]n several ways ... the most interesting woman that ever lived, and the most extraordinary".
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Sources: en.wikipedia.org
Wills Professor of Physics, University of Bristol. For services to Physics. Professor Henry John Evans. For services to Medical Research. James Stuart Fair, Chairman, Dundee Teaching Hospitals NHS Trust. For services to Health Care. Jonathan Farquharson, lately Legal Commissioner, Charity Commission. Thomas Hugh Francis Farrell, , Pro-Chancellor and Chairman of Council, University of Hull. For services to Higher Education. David Geoffrey Nigel Filkin, Secretary, Association of District Councils. For services to Local Government. Stanley Fishman, President, Cinema Exhibitors' Association. For services to the Film Industry. Frederick Forsyth, Writer. For services to Literature. Michael John Ernest Frye, Chief Executive, B. Elliott plc. For services to Business. Professor Charles Albert Eric Goodhart, Professor of Banking and Finance, London School of Economics. For services to Monetary Economics. Peter James Grant, Chairman, Highlands and Islands Airports Ltd. For services to Industry. Paul Frederick Gribble. For political service. Ewan William Harper. For services to the Church of England. Derek James Harrington, Deputy Chairman and Chief Executive, Port of Felixstowe Ltd., and Director, Hutchison International Port Holdings. For services to the Ports Industry. Peregrine Andrew Morny Cavendish, Marquess of Hartington, lately Senior Steward of the Jockey Club and Chairman, British Horse Racing Board. For services to Horse Racing. David Hewitt. For services to the Community. Pamela Jean Hibbs, , Chief Nurse and Director of Quality Assurance, Royal Hospitals NHS Trust, London.
=== Pre-cigarette === Texts on the harmful effects of smoking tobacco were recorded in the Timbuktu manuscripts. James I wrote a book that denounced tobacco smoking as: "loathsome to the eye, hateful to the nose, harmful to the brain, dangerous to the lungs". Pipe smoking gradually became generally accepted as a cause of mouth cancers following work done in the 1700s. "An association between a variety of cancers and tobacco use was repeatedly observed from the late 1800s into the early 1920s." Gideon Lincecum, an American naturalist and practitioner of botanical medicine, wrote in the early 19th century on tobacco: "This poisonous plant has been used a great deal as a medicine by the old school faculty, and thousands have been slain by it. ... It is a very dangerous article, and use it as you will, it always diminishes the vital energies in exact proportion to the quantity used – it may be slowly, but it is very sure." The 1880s invention of automated cigarette-making machinery in the American South made it possible to mass-produce cigarettes at low cost, and smoking became common. This led to a backlash and a tobacco prohibition movement, which challenged tobacco use as harmful and brought about some bans on tobacco sale and use. In 1912, American Dr. Isaac Adler was the first to strongly suggest that lung cancer is related to smoking. In 1924, economist Irving Fisher wrote an anti-smoking article for Reader's Digest which said "tobacco lowers the whole tone of the body and decreases its vital power and resistance ...
==== Methanol ==== The methanol produced by aspartame metabolism is unlikely to be a safety concern for several reasons. The amount of methanol produced from aspartame-sweetened foods and beverages is likely to be less than that from food sources already in diets. With regard to formaldehyde, it is rapidly converted in the body, and the amounts of formaldehyde from the metabolism of aspartame are trivial when compared to the amounts produced routinely by the human body and from other foods and drugs. At the highest expected human doses of consumption of aspartame, there are no increased blood levels of methanol or formic acid, and ingesting aspartame at the 90th percentile of intake would produce 25 times less methanol than what would be considered toxic.
A new French commander in chief and high commissioner, General Jean Marie de Lattre de Tassigny, was appointed in December 1950. With him began the construction of a defensive line of fortifications around the Red River Delta, to protect against Việt Minh incursions and against a possible Chinese invasion. It became known as the De Lattre Line. In 1950 and 1951, de Lattre implemented scorched earth tactics in an effort to limit Việt Minh access to food and other supplies. French forces burned crops in areas of Việt Minh activity. These tactics increased the anger of the Vietnamese people against the French and were a strategic failure. In late 1950 Giáp decided to go on a "general counteroffensive", seeking the final defeat of the French. On January 13, 1951, he moved the 308th and 312th Divisions, with more than 20,000 men, to attack Vĩnh Yên, 30 miles (48 km) northwest of Hanoi, which was manned by 6,000 French troops. Considered the first set-piece battle of the war, the Vietnamese saw initial success, although as the battle progressed, French aerial supremacy proved decisive as reinforcements flew in from the rest of Indochina and all available aircraft capable of dropping bombs was utilized to carry out what would be the largest aerial bombardment of the war. By noon of January 17, Giáp's troops withdrew in defeat. The Vietnamese had suffered 5,000–6,000 deaths and 500 combatants were captured. Giáp tried again to break the French defensive line, this time 20 miles (32 km) north-east of Haiphong in an attempt to cut the French access to the port city.
Sources: en.wikipedia.org
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine–glutamate–aspartate–glycine, also written AEDG. It was developed in Russian gerontology research and is studied for proposed effects on telomerase, melatonin regulation, and neuroendocrine function. It is not an approved pharmaceutical in the United States or the European Union.
No. Epithalamin is a peptide-rich extract prepared from bovine pineal glands, while epitalon is a short synthetic peptide designed as a defined analogue of it. The synthetic version was intended to provide a reproducible molecule with some of the same proposed biological activity.
Telomere elongation and telomerase activation have been reported in cultured human somatic cells, but evidence from living human subjects is limited and has not been independently confirmed at scale. Reported findings come largely from small studies with differing designs, so the question remains open rather than settled.
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.