This is a working overview of AEDG, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-27 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Storage temperature, solid | Approximately -20 C | Sealed, desiccated, protected from light |
| Typical identity method | Electrospray mass spectrometry | Protonated ion expected near 391 |
| Typical purity method | Reversed-phase HPLC | Ultraviolet detection near 214 nm |
| Common synonyms | Epithalon, epithalone, AEDG | Spelling variants appear in supplier catalogues |
| Solution stability | Days at 2-8 C | Hydrolysis and deamidation limit shelf life |
Purity assessment of peptide reagents normally relies on reversed-phase high-performance liquid chromatography. A gradient of acetonitrile in water with trifluoroacetic acid, paired with a C18 stationary phase, separates the target tetrapeptide from truncated sequences and deletion analogues. Detection at 214 nanometres exploits absorbance of the peptide backbone, since the molecule contains no aromatic residue. Results are expressed as a percentage of total peak area. Values above ninety-five percent are typical for research-grade material, although reporting conventions vary between suppliers.
Identity confirmation uses mass spectrometry, usually electrospray ionisation in positive mode or matrix-assisted laser desorption. The protonated free peptide produces a signal near three hundred and ninety-one daltons, while salt adducts shift that value slightly. Tandem mass spectrometry or amino acid analysis supplies sequence-level confirmation, which a single mass measurement cannot. Peptides containing aspartate can cyclise into succinimide intermediates that hydrolyse to isoaspartate isomers of identical mass. Because those isomers are difficult to separate chromatographically, identity and purity results carry more weight when interpreted together.
Storage practice centres on limiting moisture, oxygen, and repeated temperature cycling. Freeze-dried powder is generally held desiccated at minus twenty degrees Celsius or colder and protected from light. Reconstituted solutions are markedly less stable, and the aspartate-glycine junction is prone to succinimide formation at neutral to mildly alkaline pH. Portioning material into single-use aliquots reduces degradation compared with repeated freeze-thaw cycles. Stability data specific to this tetrapeptide remain scarce, so most handling guidance is extrapolated from general peptide chemistry rather than measured directly.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
Identity is normally established by reversed-phase high-performance liquid chromatography combined with mass spectrometry, a pairing that separates components and confirms molecular mass at once. Purity is quoted as a percentage from the chromatogram, and figures above ninety-five percent are a frequent commercial specification. Amino acid analysis or sequencing supplies further confirmation when required. Because many short peptides behave similarly under chromatography, retention time alone does not establish sequence; the mass measurement is what separates one tetrapeptide from another, and certificates should report both.
Short peptides such as AEDG are normally supplied as a freeze-dried solid and are kept dry, cold, and shielded from light. Holding at minus twenty degrees Celsius is common for the long term, while a refrigerator suffices for brief periods before use. The material takes up moisture to some degree, so containers should stay sealed and be allowed to reach room temperature before opening, which limits condensation on the contents. Repeated warming and cooling of a single container is discouraged because it admits water and can lower the amount of intact peptide.
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.
=== Fatty acid oxidation disorders === With the advent of tandem mass spectrometry as a screening tool, several fatty acid oxidation disorders were targeted for inclusion in newborn screening programs. Medium chain acyl-CoA dehydrogenase deficiency (MCADD), which had been implicated in several cases of sudden infant death syndrome was one of the first conditions targeted for inclusion. MCADD was the first condition added when the United Kingdom expanded their screening program from PKU only. Population based studies in Germany, the United States and Australia put the combined incidence of fatty acid oxidation disorders at 1:9300 among Caucasians. The United States screens for all known fatty acid oxidation disorders, either as primary or secondary targets, while other countries screen for a subset of these. The introduction of screening for fatty acid oxidation disorders has been shown to have reduced morbidity and mortality associated with the conditions, particularly MCADD. An Australian study found a 74% reduction in episodes of severe metabolic decompensation or death among individuals identified by newborn screening as having MCADD versus those who presented clinically prior to screening. Studies in the Netherlands and United Kingdom found improvements in outcome at a reduced cost when infants were identified before presenting clinically. Newborn screening programs have also expanded the information base available about some rare conditions.
However, it continued to conduct its work independently. In September 2022, the Lancet commission published a wide-ranging report on the pandemic, including commentary on the virus origin overseen by the group's chairman, economist Jeffrey Sachs. The report suggested that the virus may have originated from an American laboratory, a notion promoted by Sachs since late 2020, including in 2022 on the podcast of anti-vaxx conspiracy theorist Robert F. Kennedy Jr. Reacting to the Commission report, virologist Angela Rasmussen commented that this may have been "one of The Lancet's most shameful moments regarding its role as a steward and leader in communicating crucial findings about science and medicine". Virologist David Robertson said the invocation of US laboratory involvement was "wild speculation" and that "it's really disappointing to see such a potentially influential report contributing to further misinformation on such an important topic". The task force published their own report in October 2022, saying they concluded there was "overwhelming" evidence of a natural spillover, but they also accepted the possibility of a lab leak.
Environment and situation are the crucial factors that determine how corpses decay. For instance, corpses will decay differently depending on the weather, the way they are buried, and the medium in which they are buried. Peat slows the decay of corpses. It was feared that, once Lindow Man was removed from that environment, which had preserved the body for nearly 2,000 years, the remains would rapidly start to deteriorate, so steps were taken to ensure preservation. After rejecting methods that had been used to maintain the integrity of other bog bodies, such as the "pit-tanning" used on Grauballe Man, which took a year and a half, scientists settled on freeze-drying. In preparation, the body was covered in a solution of 15% polyethylene glycol 400 and 85% water to prevent it from becoming distorted. The body was then frozen solid and the ice vaporised to ensure Lindow Man did not shrink. Afterwards, Lindow Man was put in a specially constructed display case to control the environment, maintaining the temperature at 20 °C (68 °F) and the humidity at 55%.
== Research == Sinclair has expressed the view that there is no limit to human lifespan, and that there is a backup copy of the genetic and epigenetic information in us. While Sinclair was in Guarente's lab, he discovered that sirtuin 1 (called sir2 in yeast) slows aging in yeast by reducing the accumulation of extrachromosomal rDNA circles. Others working in the lab at the time identified NAD as an essential cofactor for sirtuin function. In 2002, after he had left for Harvard, he clashed with Guarente at a scientific meeting at Cold Spring Harbor Laboratory, challenging Guarente's description of how sir2 might be involved in aging; this set off a scientific rivalry. In 2003, Sinclair learned that scientists at a Pennsylvania biotech company called Biomol Research Laboratories had developed a biochemical assays in which they thought that polyphenols including resveratrol activated SIR2. This led to publications authored in part by Sinclair in both Nature and Science in 2003. However, by 2005, it became clear that the biochemical assay consists of a fluorescent probe that interacts nonspecifically with resveratrol and that resveratrol is not a SIR2 activator Despite the scientific debunking of resveratrol, Sinclair maintains an outspoken advocacy for resveratrol as an anti-aging drug and supplement. High-profile papers claiming age reversal of mice have also come under intense scrutiny. Sinclair's lab has continued to work on resveratrol and analogues of it as part of their research program in anti-aging.
=== Maxim Alonso === Maxim Alonso (Nicholas Bishop) is a hedge fund manager and old family friend of Yasmin's, placed in charge of overseeing her father Charles' assets. Maxim has a tense, quasi-brotherly relationship with Yasmin throughout series 1, especially after a client meeting with him is derailed by the misbehavior of Yasmin's abusive boss Kenny. In series 2, Maxim's fund goes bankrupt, prompting him to throw an excessive, drug-fueled party where and Yasmin end up having sex. While initially continuing their tryst, Yasmin grows distant from Maxim after becoming privy to Charles' numerous extramarital affairs and subsequent NDA settlements, which she is angry at Maxim for not telling her about. Maxim later drunkenly tries to force himself on Yasmin in bed, causing her to cut ties with him. In series 3, Maxim reaches out to Yasmin while camping in Northern California to tell her that Hanani Publishing was complicit in Charles' sexual misconduct, providing several of his victims with sham jobs in exchange for their silence. He explains that the company wants to make Yasmin the face of the scandal to hide their own involvement.
Sources: en.wikipedia.org
== Occurrence == Carotenoids are essential for animal health and functioning, but animals cannot produce them. Animals obtain carotenoids from their diet, with herbivores sourcing them from plants or algae, and carnivores, in turn, sourcing them from herbivores. Meso-zeaxanthin is not present in plants, except for marine species. Originally, it was suggested that meso-zeaxanthin present in humans and other vertebrates was non-dietary in origin, instead being biosynthesized in the macula (the central part of the retina) from retinal lutein (another xanthophyll carotenoid found in the human diet); this work has since been refuted. Consistent with work by Maoka et al. in 1986, Nolan et al. showed that meso-zeaxanthin is present in the skin of trout, sardine and salmon, and in the flesh of trout. In a subsequent publication, Nolan's group detected and quantified the three stereoisomers of zeaxanthin, including meso-zeaxanthin, in the flesh of two different trout species, which was the first report of concentrations of meso-zeaxanthin in habitually consumed food. Prior to this research, a publication from Khachick et al. (2002) reported that liver from Japanese quail (Coturnix japonica) and frog plasma contain meso-zeaxanthin. Meso-zeaxanthin may be generated from other carotenoids consumed by animals, as carotenoids can be interconverted for functional reasons. For example, it has been suggested that meso-zeaxanthin of trout integuments is derived from astaxanthin, and meso-zeaxanthin in primates is derived at least in part from lutein.
== Signs and symptoms == Muscle dysfunction and weakness – This occurs in major muscles, but also may manifest as: diplopia, low cardiac output, dysphagia, and respiratory depression due to respiratory muscle weakness. Mental status changes – This may range from irritability to gross confusion, delirium, and coma. White blood cell dysfunction, causing worsening of infections. Instability of cell membranes due to low adenosine triphosphate (ATP) levels – This may cause rhabdomyolysis with increased serum levels of creatine phosphokinase, and also hemolytic anemia. Increased affinity for oxygen in the blood caused by decreased production of 2,3-bisphosphoglyceric acid. If hypophosphatemia is chronic; rickets in children or osteomalacia in adults may develop.
The CAP has three main parts. First, the European Agricultural Guarantee Fund distributes 'direct payments', which are 70.9% of the CAP budget. The Direct Payments Regulation 2013 gives payments to an 'active farmer' that carries out agricultural activity, grazing or cultivation, does not operate airports, rail, waterworks, real estate, sport or recreation grounds, and has the land at their disposal. The farm must have at least 1 hectare and receive €100 for each, though member states can set higher thresholds (e.g. 5 hectares and €200). If payments reach over €150,000 there is a 5% reduction per hectare for each hectare. This favours large farm corporations, and the largest 1% typically receive around 10 to 15% of all subsidies in member states. As conditions of receiving subsidies, farms can be required to keep land in good condition, for public, animal, and plant health, and maintain environment standards. For minimal biodiversity, farmers must have over two crops if they have 10 hectares, not farm at least 5% of lintensively (an 'ecological focus area' over 15 hectares, and have three crops over 30 hectares. Environmentally sensitive grasslands, as designated by the Habitats Directive 1992 and the Wild Birds Directive 2009, should not be more turned into more than 5% agricultural area. The second main part, also carried out by the EAGF, is 'market measures'. Under the Agricultural Products Regulation 2013 certain crops and meat are eligible for purchase by member state authorities, to be 'stored by them until disposed of', with extra aid for storage.
There are several diagnostic and classification criteria have been proposed for dermatomyositis. Contemporary approaches generally combine clinical features with myositis-specific and myositis-associated autoantibody testing, supported by complementary laboratory, imaging, histopathologic, and electrophysiologic investigations. Some criteria are designed to establish a broad syndromic diagnosis of DM, whereas others provide greater granularity by identifying distinct autoantibody-defined clinical subsets. Despite these differences, the principal diagnostic features include:
When millimetres of mercury (or inches of mercury) are quoted today, these units are not based on a physical column of mercury; rather, they have been given precise definitions that can be expressed in terms of SI units. One millimetre of mercury is approximately equal to one torr. The water-based units still depend on the density of water, a measured, rather than defined, quantity. These manometric units are still encountered in many fields. Blood pressure is measured in millimetres (or centimetres) of mercury in most of the world, and lung pressures in centimetres of water are still common. Underwater divers use the metre sea water (msw or MSW) and foot sea water (fsw or FSW) units of pressure, and these are the units for pressure gauges used to measure pressure exposure in diving chambers and personal decompression computers. Gauge pressure is often given in units with "g" appended, e.g. "kPag", "barg" or "psig", and units for measurements of absolute pressure are sometimes given a suffix of "a", for example "kPaa", "psia". However, the US National Institute of Standards and Technology recommends that, to avoid confusion, any modifiers be instead applied to the quantity being measured rather than the unit of measure. For example, "pg = 100 psi" rather than "p = 100 psig". Differential pressure is expressed in units with "d" appended; this type of measurement is useful when considering sealing performance or whether a valve will open or close. Presently or formerly popular pressure units include the following:
Sources: en.wikipedia.org
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.
Reversed-phase chromatography with ultraviolet detection gives a purity percentage, while mass spectrometry confirms identity. Amino acid analysis checks the residue composition. Buyers typically request a certificate of analysis showing these measurements for the specific lot.
It is not authorised as a medicine in the United States or the European Union. Material is sold there as a research chemical or cosmetic ingredient. Some related short peptides are registered drugs in Russia, which is a distinct national situation rather than a general approval.
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.