If you have been reading about epithalamin and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-12-26. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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 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.
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5 January – Chris Skidmore, MP for Kingswood, announces his intention to stand down from Parliament "as soon as possible" in protest at the UK government's decision to issue more oil and gas licences. His decision triggers another by-election. 6 January – Government papers seen by the BBC indicate Sunak had significant doubts about sending migrants to Rwanda when he was chancellor, and wanted to scale back the plans. Jeremy Miles rules out reversing Wales's 20 mph speed limit if he becomes first minister. 7 January – Sunak describes the Post Office scandal as "an appalling miscarriage of justice" and says the government is looking at ways to clear the names of those convicted because of faulty IT software. Helen Harrison, the partner of former Conservative MP Peter Bone, is chosen by the Conservatives to contest the 2024 Wellingborough by-election. The Independent Parliamentary Standards Authority is to investigate allegations that Pensions Minister Paul Maynard breached Parliamentary rules by using public funds to pay for Conservative Party work and campaigns. Sir Keir Starmer admits he worries about the toll of a general election year on his two teenage children as he and his wife try to keep them out of the public eye. 8 January – Green Party co-leader Carla Denyer confirms the party intends to stand a candidate in every constituency in England and Wales at the forthcoming general election, the first time it has fielded a full list of candidates at an election.
Dysphoria and apathy (due to dopamine receptor blockade) Sedation (particularly common with asenapine, clozapine, olanzapine, quetiapine, chlorpromazine and zotepine) Headaches Dizziness Diarrhea Anxiety Extrapyramidal side effects (particularly common with first-generation antipsychotics), which include: Akathisia, an often distressing sense of inner restlessness. Dystonia, an abnormal muscle contraction Pseudoparkinsonism, symptoms that are similar to what people with Parkinson's disease experience, including tremulousness and drooling Hyperprolactinaemia (rare for those treated with clozapine, quetiapine and aripiprazole), which can cause: Galactorrhoea, the unusual secretion of breast milk. Gynaecomastia, abnormal growth of breast tissue Sexual dysfunction (in both sexes) Osteoporosis Orthostatic hypotension Weight gain (particularly prominent with clozapine, olanzapine, quetiapine and zotepine, can be counteracted by starting the drug with metformin) Antipsychotic medication-induced weight gain (AIWG) is a difficult-to-manage condition. In a meta-analysis analyzing data from 9 studies having more than 40,000 patients with AIWG, use of semaglutide was on an average was associated with 7.37kg weight loss with a good reduction in waist circumference. The occurrence of psychiatric adverse events was lower in semaglutide users.
"A/B testing" is a shorthand for a simple randomized controlled experiment, in which a number of samples (e.g. A and B) of a single vector-variable are compared. A/B tests are widely considered the simplest form of controlled experiment, especially when they only involve two variants. However, by adding more variants to the test, its complexity grows. The following example illustrates an A/B test with a single variable: A company has a customer database of 2,000 people and launches an email campaign with a discount code in order to generate sales through its website. The company creates two versions of the email with different calls to action (the part of the copy that encourages customers to act—in the case of a sales campaign, make a purchase) and identifying promotional codes.
Sources: en.wikipedia.org
The reticulocyte production index (RPI), also called a corrected reticulocyte count (CRC), is a calculated value used in the diagnosis of anemia. This calculation is necessary because the raw reticulocyte count is misleading in anemic patients. The problem arises because the reticulocyte count is not really a count but rather a percentage: it reports the number of reticulocytes as a percentage of the number of red blood cells. In anemia, the patient's red blood cells are depleted, creating an erroneously elevated reticulocyte count.
The Copenhagen physicists then started a campaign to re-award priority for element 71 to Welsbach and replace the name lutetium with cassiopeium, writing to Welsbach in 1923 of their intentions. This campaign encountered success in the physics literature, but in spite of strong German and Scandinavian support for cassiopeium, lutetium remained embedded in most of the chemical literature, with the International Commission on Atomic Weights in 1930 accepting that element 72 was hafnium but using lutetium for element 71. In 1949, it was decided by the International Union of Pure and Applied Chemistry to recommend the name lutetium, since cassiopeium by then was only used in German and sometimes Dutch, and it was a difficult name to adapt to other languages. It was nonetheless clarified that this was not intended as a statement on priority. Urbain's spelling lutecium was changed to lutetium, in order to derive the name from Latin Lutetia instead of French Lutèce. Pure lutetium metal was first produced in 1953.
Miglitol is an oral alpha-glucosidase inhibitor used in the treatment of type 2 diabetes. It works by reversibly inhibiting alpha-glucosidase enzymes in the small intestine, which delays the digestion of complex carbohydrates and subsequently reduces postprandial glucose levels. Approved for clinical use since 1998, miglitol has demonstrated efficacy in improving glycemic control, reducing HbA1c levels, and decreasing both fasting and postprandial plasma glucose concentrations in long-term clinical trials. Additionally, recent studies have suggested that miglitol may have potential as an anti-obesity agent, showing promise in reducing body weight and body mass index in obese or diabetic patients. While generally well-tolerated, the most common side effects associated with miglitol are gastrointestinal disturbances, which are typically mild to moderate and tend to decrease over time. It must be taken at the start of main meals to have maximal effect In contrast to acarbose (another alpha-glucosidase inhibitor), miglitol is systemically absorbed; however, it is not metabolized and is excreted by the kidneys.
===== Euarchontoglires ===== Order Lagomorpha Family Leporidae Oryctolagus cuniculus, European rabbit (2010) Order Primates Family Callitrichidae Callithrix jacchus, Common marmoset (2010, whole genome 2014) Family Cercopithecidae Macaca mulatta, rhesus macaque (2007 & Chinese rhesus macaque Macaca mulatta lasiota in 2011) Macaca fascicularis, Cynomolgus or crab-eating macaque (2011) Papio anubis, olive baboon (2020) Papio cynocephalus, yellow baboon (2016) Rhinopithecus roxellana, golden snub-nosed monkey (2019) Family Galagidae Otolemur garnettii, small-eared galago, or bushbaby () Family Hominidae Subfamily Ponginae Pongo pygmaeus/Pongo abelii, orangutan (Borneo/Sumatra) (2011) Subfamily Homininae Gorilla gorilla, western gorilla (2012) Homo sapiens, modern human (draft 2001, whole genome 2022) † Homo neanderthalensis, Neanderthal (draft 2010) Pan troglodytes, chimpanzee (2005) Pan paniscus, bonobo (2012) Order Rodentia Family Caviidae Hydrochoerus hydrochaeris, capybara (2018) Family Cricetidae Microtus montanus, Montane vole (2021) Microtus richardsoni, North American Water Vole (2021) Peromyscus leucopus, white-footed mouse (2019) Family Heteromyidae Perognathus longimembris pacificus, Pacific Pocket Mouse Family Muridae Mastomys coucha, Southern multimammate mouse (2019) Mus musculus Strain: C57BL/6J, House mouse (2002) Rattus norvegicus, Brown rat (2004)
== Acquiring and manufacturing climbing gear == In the early 1950s, most American climbers imported climbing equipment from Europe or acquired it from US Army surplus. Pitons from these sources were made of mild steel that twisted and became unusable after only a few placements. Gallwas recognized the problem and was among the first to make and use heat-treated chrome-molybdenum steel alloy pitons. He patterned his pitons after John Salathé's so they could be placed hundreds of times without twisting. These improved pitons proved instrumental to the success of the first ascent of the Northwest Face of Half Dome in 1957. That same year, Yvon Chouinard began to produce and sell alloy-steel pitons. Chouinard's success with his pitons led him to establish Chouinard Equipment, Ltd, which later became Black Diamond Equipment, Ltd.
Sources: en.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
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.