AEDG is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-06-27. Where a claim depends on a specific study, the study is described rather than over-claimed.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
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.
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
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.
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.
=== Chemical peels === Chemical peels are chemicals which destroy the epidermis in a controlled manner, leading to exfoliation and the alleviation of certain skin conditions, including superficial acne scars. Various chemicals can be used depending upon the depth of the peel, and caution should be used, particularly for dark-skinned individuals and those individuals susceptible to keloid formation or with active infections.
=== The last thirteen === Meanwhile, the American team had created seaborgium, and the next six elements had been created by a German team: bohrium, hassium, meitnerium, darmstadtium, roentgenium, and copernicium. Element 113, nihonium, was created by a Japanese team; the last five known elements, flerovium, moscovium, livermorium, tennessine, and oganesson, were created by Russian–American collaborations and complete the seventh row of the periodic table.
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In 1945, the Vietnamese were locked in a struggle over the destiny of their post-colonial state after the ousting of the French and the surrender of Japan. Viet Minh forces seized control from the collapsing Empire of Vietnam, while the Vietnam Nationalist Party and Việt Cách advanced in Tonkin with the support of the Chinese Allied mission, and the Đại Việt Nationalist Party already posed serious competition to the Viet Minh. The South fractured between the Stalinist front Viet Minh and rival groups including the Trotskyists, Hòa Hảo, Cao Đài, and Bình Xuyên. The Indochinese Communist Party was primarily responsible for starting widespread Vietnamese-on-Vietnamese violence. Its Viet Minh front aimed to consolidate power through the terrorization and purging of the rival Vietnamese groups. In 1946, the Franco-Chinese and Ho–Sainteny Agreements enabled French forces to replace the Chinese north of the 16th parallel and facilitated a coexistence between the DRV and the French that strengthened the Viet Minh while undermining the nationalists. That summer, the Viet Minh colluded with French forces to eliminate nationalists, targeted for their ardent anti-colonialism. By eliminating the nationalist parties, the Viet Minh had undermined Vietnam's broader ability to resist French reconquest. The Bình Xuyên organized crime group also sought power in the country and although they initially fought alongside the Việt Minh, they would later support Bảo Đại.
Sources: en.wikipedia.org
Binding of activated TGF-β to its receptors expressed on alveolar macrophages induces a downstream signaling cascade, including phosphorylation of receptor-regulated Small Mothers Against Decapentaplegic (R-SMAD)homologs 2 and 3. Phosphorylated SMAD-2 and -3 then form heteromeric complexes with common-mediator SMAD 4 (co-SMAD-4). Once assembled, the complexes translocates into the nucleus via the nuclear pore with the assistance of importins alpha/beta. Once in the nucleus, these complexes accumulate and eventually act as a transcription factors, regulating the expression of TGF-β target genes. Thus TGF-β signaling involves a direct pathway from the receptors on the surface of a cell to the nucleus.
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At launch, it received mediocre reviews for its lack of significant gameplay and visual enhancements, although IGN still recommended it. Retrospective reception has been more negative, owing to the game's instability and frequent glitches. The deathmatch mode was ported to Source separately in 2006 as Half-Life Deathmatch: Source. Following the release of the Half-Life 25th anniversary update in 2023, Half-Life: Source was delisted from Steam and does not appear in its search results, it is now bundled for free with Half-Life Deathmatch: Source, which remains available. Black Mesa, a third-party remake of Half-Life developed by Crowbar Collective on the Source engine, was published as a free mod in September 2012 and later approved by Valve for a commercial standalone release.
Plant hormones (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, including embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in vascular plants ("higher plants"). Some phytohormones also occur in microorganisms, such as unicellular fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites.
Sources: en.wikipedia.org
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
It is a synthetic tetrapeptide built from alanine, glutamate, aspartate and glycine. The four residues are joined by standard peptide bonds, giving a linear chain rather than a branched structure.