Everything below concerns epitalon. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-12-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
The most frequently cited proposed action is induction of telomerase, the enzyme that adds repeat sequences to chromosome ends. Cell-culture work from the originating group reported higher telomerase reverse transcriptase expression and measurable telomere elongation in human somatic cells after exposure. How a four-residue peptide would reach nuclear gene regulation is not established, and no cell-surface receptor or uptake route has been identified. Additional reports describe changes in melatonin secretion, antioxidant enzyme activity and lipid peroxidation in aged animals, but these findings remain mechanistically unconnected to the telomerase observation.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Calculated from the four residues with three water losses |
| Molecular mass | About 390.35 g/mol | Monoisotopic mass near 390.14, used for mass-spectrometric identification |
| Peptide sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG; no disulfide bonds or modified residues |
| Appearance | White to off-white solid | Supplied as a dried powder |
| Isoelectric point | Around 4 | Estimated from aspartate and glutamate side-chain pKa values |
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.
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.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
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.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
=== The 1990s === Douglas Hart had moonlighted with the Acid Angels in 1988, and left the band in 1991, to have a career in film making, before picking up his bass again in 2006, playing with the Sian Alice Group, Le Volume Courbe, and Cristine. Thomas also quit the band to join Renegade Soundwave. The fluid nature of the Mary Chain's line up continued throughout their entire career, with a revolving door of drummers, bassists and guitarists being recruited for TV appearances and gigs whenever they were required, the only constants being the Reid brothers. The Reid brothers recruited former Starlings rhythm section Matthew Parkin and Barry Blackler to replace Hart and Thomas. The brothers bought their own recording studio in 1991 in Elephant & Castle in South London, which they dubbed The Drugstore, and they returned in February 1992 with the first fruits of the new studio, their next single, "Reverence", which gave them their biggest hit single in almost five years, reaching No. 10 in the UK. Spitting feedback and punk rock bile in every direction, the track was banned from being played on BBC Radio 1 and from Top of the Pops, due to its potentially offensive lyrics ('I wanna die just like JFK, I wanna die in the USA'...'I wanna die just like Jesus Christ, I wanna die on a bed of spikes'). The single was followed by the release of the album Honey's Dead (1992), which received mixed reviews.
The majority of Guatemalan migrants were from indigenous populations like the Mopan Maya or Kekchi Maya Indians, and many remained in urban areas for economic opportunity, while native Belizeans moved to rural areas.
=== Infection === Common infectious causes of back pain include osteomyelitis, septic discitis, paraspinal abscess and epidural abscess. Infectious causes that lead to back pain involve various structures surrounding the spine. Osteomyelitis is the bacterial infection of the bone. Vertebral osteomyelitis is most commonly caused by staphylococci. Risk factors include skin infection, urinary tract infection, IV catheter use, IV drug use, previous endocarditis and lung disease. Spinal epidural abscess is commonly caused by severe infection with bacteremia. Risk factors include recent administration of epidurals, IV drug use or recent infection.
== P == Paal–Knorr pyrrole synthesis Paal–Knorr synthesis Paneth technique Passerini reaction Paternò–Büchi reaction Pauson–Khand reaction Payne rearrangement Pechmann condensation Pechmann pyrazole synthesis Pellizzari reaction Pelouze synthesis Peptide synthesis Perkin alicyclic synthesis Perkin reaction Perkin rearrangement Perkow reaction Petasis reaction Petasis reagent Peterson olefination Peterson reaction Petrenko-Kritschenko piperidone synthesis Pfau–Plattner azulene synthesis Pfitzinger reaction Pfitzner–Moffatt oxidation Phosphonium coupling Photosynthesis Piancatelli rearrangement Pictet–Gams isoquinoline synthesis Pictet–Hubert reaction Pictet–Spengler tetrahydroisoquinoline synthesis Pictet–Spengler reaction Piloty–Robinson pyrrole synthesis Pinacol coupling reaction Pinacol rearrangement Pinner amidine synthesis Pinner method for ortho esters Pinner reaction Pinner triazine synthesis Pinnick oxidation Piria reaction Polonovski reaction Pomeranz–Fritsch reaction Ponzio reaction Prato reaction Prelog strain Prevost reaction Prileschajew reaction Prilezhaev reaction Prins reaction Prinzbach synthesis Protecting group Pschorr reaction Pummerer rearrangement Purdie methylation, Irvine–Purdie methylation
Sources: en.wikipedia.org
== Mechanism of action == Azacitidine is a chemical analogue of the nucleoside cytidine, which is present in DNA and RNA. It is thought to have antineoplastic activity via two mechanisms – at low doses, by inhibiting of DNA methyltransferase, causing hypomethylation of DNA, and at high doses, by its direct cytotoxicity to abnormal hematopoietic cells in the bone marrow through its incorporation into DNA and RNA, resulting in cell death. Azacitidine is a ribonucleoside, so it is incorporated into RNA to a larger extent than into DNA. In contrast, decitabine (5-aza-2'-deoxycytidine) is a deoxyribonucleoside, so it can only incorporate into DNA. Azacitidine's incorporation into RNA leads to the disassembly of polyribosomes, defective methylation and acceptor function of transfer RNA, and inhibition of the production of proteins. Its incorporation into DNA leads to covalent binding with DNA methyltransferases, which prevents DNA synthesis and subsequently leads to cytotoxicity. It has been shown effective against human immunodeficiency virus in vitro and human T-lymphotropic virus.
== History & etymology == It had been known to physiologists for over a century that a vasoconstrictor material appears in serum when blood was allowed to clot. In 1935, Italian Vittorio Erspamer, working in Pavia, showed an extract from enterochromaffin cells made intestines contract. Some believed it contained adrenaline, but two years later, Erspamer was able to show it was a previously unknown amine, which he named "enteramine". In 1948, Maurice M. Rapport, Arda Green, and Irvine Page of the Cleveland Clinic discovered a vasoconstrictor substance in blood serum, and since it was a serum agent affecting vascular tone, they named it serotonin. In 1952, enteramine was shown to be the same substance as serotonin, and as the broad range of physiological roles was elucidated, the abbreviation 5-HT of the proper chemical name 5-hydroxytryptamine became the preferred name in the pharmacological field. Synonyms of serotonin include: 5-hydroxytriptamine, enteramine, substance DS, and 3-(β-aminoethyl)-5-hydroxyindole. In 1953, Betty Twarog and Page discovered serotonin in the central nervous system. Page regarded Erspamer's work on Octopus vulgaris, Discoglossus pictus, Hexaplex trunculus, Bolinus brandaris, Sepia, Mytilus, and Ostrea as valid and fundamental to understanding this newly identified substance, but regarded his earlier results in various models – especially those from rat blood – to be too confounded by the presence of other bioactive chemicals, including some other vasoactives.
In the early stages after the procedure, the use of interdental brushes is strongly advised against due to the potential damage to interdental tissues in the operated area, toothpicks are recommended as an alternative. The patient is asked to visit every two weeks for monitoring of their plaque levels. The time between visits will gradually increase if the patients’ plaque control is up to standard.
Several predictions have been made regarding the exact location of the island of stability, though it is generally thought to center near copernicium and flerovium isotopes in the vicinity of the predicted closed neutron shell at N = 184. These models strongly suggest that the closed shell will confer further stability towards fission and alpha decay. While these effects are expected to be greatest near atomic number Z = 114 (flerovium) and N = 184, the region of increased stability is expected to encompass several neighboring elements, and there may also be additional islands of stability around heavier nuclei that are doubly magic (having magic numbers of both protons and neutrons). Estimates of the stability of the nuclides within the island are usually around a half-life of minutes or days; some optimists propose half-lives on the order of millions of years. Although the nuclear shell model predicting magic numbers has existed since the 1940s, the existence of long-lived superheavy nuclides has not been definitively demonstrated. Like the rest of the superheavy elements, the nuclides within the island of stability have never been found in nature; thus, they must be created artificially in a nuclear reaction to be studied. Scientists have not found a way to carry out such a reaction, for it is likely that new types of reactions will be needed to populate nuclei near the center of the island.
The research, as cited by the cover story of the November 2005 issue of National Geographic, asserts that Adventists live longer because they do not smoke or drink alcohol, have a day of rest every week, and maintain a healthy, low-fat vegetarian diet that is rich in nuts and beans. The cohesiveness of Adventists' social networks has also been put forward as an explanation for their extended lifespan. Since Dan Buettner's 2005 National Geographic story about Adventist longevity, his book, The Blue Zones: Lessons for Living Longer From the People Who've Lived the Longest, named Loma Linda, California, a "blue zone" because of the large concentration of Seventh-day Adventists. He cites the Adventist emphasis on health, diet, and Sabbath-keeping as primary factors for Adventist longevity. An estimated 35% of Adventists practice vegetarianism or veganism, according to a 2002 worldwide survey of local church leaders. North American Adventist health study recruitments from 2001 to 2007 found a similar prevalence of vegetarianism/veganism. A small majority of Adventists, 54%, were conventional meat-eaters. Of the remaining 46% it was found that 28% were Ovo/Lacto-vegetarians, 10% were Pesco-vegetarians and 8% were vegans. It is common for Adventists who choose to eat meat to also eat plant-based foods; 6% of the "meat-eaters" group restricted their intake of meat/fish to no more than once per week.
Sources: en.wikipedia.org
In November 2022, it was announced that McDonald's was leaving Belarus on 22 November and that the Russian fast food chain Vkusno i tochka would take its place. However, this did not happen, and the operations of McDonald's was extended until 27 November; since then, the restaurants operated under the sign "We are open!" (Russian: Мы открыты!, IPA: [ˌmɨ ɐtˈkrɨtɨ]). In early April 2023, KSB Victory Restaurants (Russian: КСБ Виктори Рестораны, IPA: [ˌkaɛzˈbɛ vʲɪkˈtorʲɪ rʲɪstɐˈranɨ]), operators of McDonald's in the country, filed an application for registration of the name and trademark "Mak.by". On April 18, 2023, the restaurant chain was renamed Mak.by.
== Principle == Peptides are very useful as therapeutic and diagnostic substances. Their use is getting more popular, and display systems offer a useful way to engineer peptides and optimise their binding capabilities. Cells express surface proteins which can be involved in a whole host of responses including recognition of other cells, interaction with other cells, and cell signalling. Many types of bacteria have cell surface proteins such as the enteropathogenic E. coli intimin protein which is involved in binding to host cells, or the OmpA protein of E. coli cells which is important in keeping the structure of the outer membrane. Many surface proteins are involved in bacterial cell attachment and invasion of the host cell. By using bacterial display, target proteins on the host cell can be identified. These surface proteins need to first be translocated across the bacterial cell membranes from the cytoplasm to the cell surface. Gram-negative bacteria have an additional periplasmic space, which Gram-positive bacteria lack, so they have a harder task of translocating proteins. The display of heterologous proteins on the bacterial cell surface normally requires the fusion of the protein with a surface protein, called a scaffold.
The required oxygen functionality was then introduced via epoxidation followed by a Lewis acid-catalyzed SN2′-type ring-opening reaction with allyl alcohol. This led to an intermediate that had previously been converted to Guanacastepene A by other groups. Thus, the formal synthesis could be considered complete.
163 (4): 689–696. doi:10.1176/appi.ajp.163.4.689. PMID 16585445. Sciacca, K. (1997). "Peer Support for People Challenged by Dual Diagnosis: 'Helpful People in Touch' (Consumer Led Self-Help)" (PDF). In Mowbray, C.T.; Moxley, D.P.; Jasper, C.A.; Howell, L.L. (eds.). Consumers as Providers in Psychosocial Rehabilitation. IAPSRS Publisher. p. 82. Archived from the original (PDF) on 1 February 2012. Retrieved 2 September 2011. Adamson, Simon J.; Todd, Fraser C.; Douglas Sellman, J.; Huriwai, Terry; Porter, Joel (2006). "Coexisting Psychiatric Disorders in a New Zealand Outpatient Alcohol and other Drug Clinical Population". Australian & New Zealand Journal of Psychiatry. 40 (2): 164–170. doi:10.1080/j.1440-1614.2006.01764.x. PMID 16476135. S2CID 208628311.
Sources: en.wikipedia.org
No. Epithalamin is a peptide-containing extract of bovine pineal glands, while epitalon is a single synthetic tetrapeptide. The extract contains many peptides and other tissue components, so its composition varies between batches in ways that a synthesised sequence does not.
It is not recognised as an endogenous peptide hormone. The four-residue sequence can appear inside larger proteins and in digestive fragments of dietary protein, but no dedicated pathway producing it as a signalling molecule has been identified.
Several cell-culture reports describe increased telomerase activity after treatment, measured by enzyme assays or by transcript levels. Results differ between cell types and laboratories, and measured telomere lengthening has been reported in some studies but not in others, which leaves the physiological relevance open.
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.