Everything below concerns tetrapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-12-17. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Linear tetrapeptide | Four residues joined by three peptide bonds |
| Sequence | Ala-Glu-Asp-Gly | Commonly abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free acid form |
| Monoisotopic mass | Approximately 390 Da | Matches values reported from mass spectrometry |
| Net charge near neutral pH | Negative | Contributed by glutamate and aspartate side chains |
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.
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 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.
Rezafungin, sold under the brand name Rezzayo (by Melinta Therapeutics), is a medication used for the treatment of invasive candidiasis. It is an echinocandin antifungal that acts as a fungal β-glucan synthase inhibitor. Rezafungin was approved for medical use in the United States in March 2023, and in the European Union in December 2023.
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With 68.6 million tons of cargo in 2011, the port of Le Havre is the second largest French seaport in trade volume behind that of Marseille and 50th largest port in the world. It represents 60% of total French container traffic with nearly 2.2 million Twenty-foot equivalent unit|EVP]s in 2011. At the European level, it is eighth largest for container traffic and sixth largest for total traffic. The Port receives a large number of oil tankers that transported 27.5 million tonnes of crude oil and 11.7 million tonnes of refined product in 2011. Finally, 340,500 vehicles passed through the Roll-on/roll-off terminal in 2010. 75 regular shipping lines serve 500 ports around the world. The largest trading partner of the port of Le Havre is the Asian continent which alone accounts for 58% of imports by container and 39.6% of exports. The rest of the traffic is distributed mainly to Europe and America. Le Havre occupies the north bank of the estuary of the Seine on the Channel. Its location is favourable for several reasons: it is on the most frequented waterway in the world; it is the first and last port in the North Range of European ports – the largest in Europe which handles a quarter of all global maritime trade. As a deepwater port, it is accessible to all types of ships whatever their size around the clock. At the national level, Le Havre is 200 kilometres (124 mi) west of the most populous and richest region in France: Île-de-France.
Sources: en.wikipedia.org
=== 5 April === Ukraine launched a barrage of drones into western Russia, targeting four airbases. Ukrainian officials claim at least six military aircraft were destroyed, eight others were "heavily damaged", and at least 20 personnel were killed or injured at a military airbase near Morozovsk, Rostov Oblast. Security sources reported the airbase held Su-27 and Su-34 aircraft, while an open-source intelligence researcher reported the base also held three Su-35 aircraft. Rostov Oblast Governor Vasily Golubev claimed Russia intercepted 44 Ukrainian drones and that only a 16-storey residential block and power substation were damaged, leaving around 600 people without power. Eight people were later injured by one of the fallen drone's explosives detonating during an investigation of the site. Drones were also launched at Engels-2 airbase in Saratov Oblast, reportedly home to Tu-95 and Tu-22 bombers. The attack allegedly caused "serious damage" to three Tu-95MS bombers and resulted in the deaths of seven. One drone was shot down over the nearby town of Engels. There were no reports of casualties or infrastructure damage from the neutralized drone. Yeysk Airport, which hosts the aviation units of the 4th Army of the Russian Air Force, was also allegedly struck, with four Russians killed and two Su-25 aircraft destroyed. Local official Roman Bublik denied any damage. Kursk Vostochny Airport was also targeted. There was no information provided on possible damage. Russia reported no casualties and denied any serious damage, claiming to have intercepted 53 drones.
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Sources: en.wikipedia.org
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Sources: en.wikipedia.org
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.
The compound came out of work on epithalamin, a peptide preparation derived from pineal tissue, conducted largely in Russian laboratories. Later studies in other countries examined it mainly in cell cultures and animal models.
The tetrapeptide sequence is a synthetic construct rather than a described circulating peptide. It was derived by analogy to peptide fractions obtained from tissue extracts, not isolated from blood or tissue as such.
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.