A practical reference on Research chemical: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-06-10 and is reviewed periodically as new material appears.
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.
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 | 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 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.
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.
=== Classification of metal ions === Ahrland, Chatt and Davies proposed that metal ions could be described as class A if they formed stronger complexes with ligands whose donor atoms are nitrogen, oxygen or fluorine than with ligands whose donor atoms are phosphorus, sulfur or chlorine and class B if the reverse is true. For example, Ni2+ forms stronger complexes with amines than with phosphines, but Pd2+ forms stronger complexes with phosphines than with amines. Later, Pearson proposed the theory of hard and soft acids and bases (HSAB theory). In this classification, class A metals are hard acids and class B metals are soft acids. Some ions, such as copper(I), are classed as borderline. Hard acids form stronger complexes with hard bases than with soft bases. In general terms hard–hard interactions are predominantly electrostatic in nature whereas soft–soft interactions are predominantly covalent in nature. The HSAB theory, though useful, is only semi-quantitative. The hardness of a metal ion increases with oxidation state. An example of this effect is given by the fact that Fe2+ tends to form stronger complexes with N-donor ligands than with O-donor ligands, but the opposite is true for Fe3+.
. Salts of these species have been isolated in the cases of dibenzocyclooctatetraene, various tertiary amines, and some polymethylated derivatives of azulene. Radical cations, like radical anions, have one unpaired electron, i.e. they are paramagnetic.
McKew said that "Putin and his minions have spent the past 15 years ranting about how the West (specifically NATO) wants a new Cold War". She suggested that "fighting a new Cold War would be in America's interest", adding "We won the last Cold War. We will win the next one too". The New Republic editor Jeet Heer criticised McKew's suggestion as "troubling" and for "wildly overstating the extent of Russian ambitions and power". Heer said that unlike the old Cold War, "Current U.S. troubles with Russia aren't the result of ideological differences ... and are intensely localized along Russia's borders, in countries like the Ukraine and Georgia". Jeremy Shapiro, a senior fellow in the Brookings Institution, wrote in his blog post at RealClearPolitics, referring to the US–Russia relations: "A drift into a new Cold War has seemed the inevitable result" of "Russian–Western confrontation" over Eastern European counties such as Ukraine, Moldova and Georgia. In August 2017, Russian Deputy Foreign Minister Sergei Ryabkov denied claims that the US and Russia were having another cold war, despite ongoing tensions between the two countries over Ukraine and Syria, and newer US sanctions against Russia. The University of East Anglia graduate student Oliver Steward, as well as the Casimir Pulaski Foundation senior fellow Stanisław Koziej, attributed the Russia's Zapad 2017 exercise in Belarus as part of the new Cold War between Russia and the West.
In 2001, the LRP-I was merged with the MCW to create the consolidated Meal, Cold Weather/Food Packet, Long Range Patrol (MCW/LRP) ration. As in years past, this was done in order to further standardize supply and save costs, as both were considered compact, high-energy meals that were designed for use by active soldiers in the field. The meal weighs 1 pound (454 g) and comes in 12 different entrees. The meals differ only in the accessory packs. One is geared for use by light infantry and commando units operating in temperate or hot climates and comes in brown or tan packaging. The other is geared more for use in cold weather or high elevations and comes in white packaging.
Sources: en.wikipedia.org
Another ancient way of preparing potatoes in the Andes was by mimicking native wildlife, specifically, wild relatives of the llama. They would lick clay before eating wild poisonous potatoes which would help negate the toxins. The people of the Andes copied this by creating a mixture of clay and water to dunk the potatoes into so they could eat them as well. The need for this mixture mostly disappeared with the selective breeding of non-poisonous potatoes but the practice remains in use where the old species of poisonous potatoes are still grown. Chuño is still produced in the Andean Altiplano, specifically in the Suni and Puna regions, which are the only regions with suitable eco-climatic conditions, and is consumed in Argentina, Bolivia, Chile and Peru. According to the botanist R.N. Salaman, in prehistoric times, chuño was ground into flour and incorporated into all kinds of stews and chupes, a kind of hearty soup of very ancient origin, but still cooked. Another traditional product of the Altiplano is tocosh, obtained from the fermentation of potatoes left in a stream of water for at least six months. This product, considered to have probiotic properties, is used in the preparation of a local dessert, the mazamorra de papas.
== Controversy == Scientists associated with the initial development of recombinant DNA methods recognized that the potential existed for organisms containing recombinant DNA to have undesirable or dangerous properties. At the 1975 Asilomar Conference on Recombinant DNA, these concerns were discussed and a voluntary moratorium on recombinant DNA research was initiated for experiments that were considered particularly risky. This moratorium was widely observed until the US National Institutes of Health developed and issued formal guidelines for rDNA work. Today, recombinant DNA molecules and recombinant proteins are usually not regarded as dangerous. However, concerns remain about some organisms that express recombinant DNA, particularly when they leave the laboratory and are introduced into the environment or food chain. These concerns are discussed in the articles on genetically modified organisms and genetically modified food controversies. Furthermore, there are concerns about the by-products in biopharmaceutical production, where recombinant DNA result in specific protein products. The major by-product, termed host cell protein, comes from the host expression system and poses a threat to the patient's health and the overall environment.
The Sue Golding Graduate Division was established in 1957 to offer Doctor of Philosophy (PhD) degrees in biomedical science. In 1963, Einstein established its Department of Genetics, the first at any at any medical school; the coursework it offered was possibly the first formal medical curriculum on genetics. The following year, the Medical Scientist Training Program (MSTP), a combined MD/PhD program, was established. The first successful coronary artery bypass surgery was performed in 1960 at Einstein by a team led by Robert H. Goetz; the procedure has been described in The Annals of Thoracic Surgery as "one of the most significant surgical achievements of the 20th century". In 1966, the school completed a 375-bed private teaching hospital—now known as the Jack D. Weiler Hospital—with New York City Mayor John Lindsay presiding over its opening. The Ullmann Research Center for Health Sciences, a 12-story facility, opened in 1964. The following year, the Joseph P. Kennedy Jr. Foundation donated $1.45 million to Einstein to establish a center to study human development and mental disabilities. The center, named for Rose F. Kennedy, opened with 200 staff scientists in 1970. Also that year, the college began construction on the 15-story Charles C. and Beulah Bassine Educational Center devoted to public health. Beginning in 1971, aided by a five-year, $12,157,000 federal grant, the college experimented with a 3-year MD degree pathway and increased class sizes.
=== Topical === Throughout clinical trials, data from a limited number of exposed pregnancies indicate that there is no clinical evidence that treatment with eflornithine adversely affects pregnant women or fetuses.
In more severe cases it is a consequence of dilation of the right ventricle, leading to displacement of the papillary muscles which control the valve's ability to close. Dilation of the right ventricle occurs secondary to ventricular septal defects, right to left shunting of blood, eisenmenger syndrome, hyperthyroidism, and pulmonary stenosis. Tricuspid insufficiency may also be the result of congenital defects of the tricuspid valve, such as Ebstein's anomaly.
Sources: en.wikipedia.org
== Clinical significance == FAP expression is seen on activated stromal fibroblasts of more than 90% of all human carcinomas. Stromal fibroblasts play an important role in the development, growth and metastasis of carcinomas. Several approaches to FAP targeting in cancer diagnosis and treatment are currently being tested. In diagnostic imaging radiolabeled FAP inhibitors (FAPIs) are used as PET tracers to visualize tumors. Therapeutic approaches include the use of low molecular weight inhibitors, prodrugs activated by FAP, various anti-FAP antibodies and their conjugates, FAP-CAR T cells, and FAP vaccines. By cleaving FGF-21, FAP is also thought to play a possible role in energy metabolism. Talabostat is an inhibitor of FAP and related enzymes, for which clinical trials have been done, but further research is suspended. Sibrotuzumab is a monoclonal antibody against FAP.
== Chemical modifications == Creating chemically stable short oligonucleotides was the earliest challenge in developing ASO therapies. Naturally occurring oligonucleotides are easily degraded by nucleases, an enzyme that cleaves nucleotides and is ample in every cell type. Short oligonucleotide sequences also have weak intrinsic binding affinities, which contributes to their degradation in vivo.
However, market observers have suggested the pushback from central bankers, professional economists, and congressional Republicans may have led many investors to conclude that the investigation probably will not lead to a long-term shift in the central bank's independence. Powell could remain the Federal Reserve Chair if the United States Senate does not confirm a replacement while Powell's term as a Federal Reserve Governor does not expire until 2028, and some observers have suggested that Powell may choose to serve the entire term to help preserve the central bank's independence—like Federal Reserve Chair Marriner Eccles did after President Harry S. Truman declined to reappoint Eccles as chair in 1948 and led to the Federal Reserve's 1951 Accord with the Treasury Department. Powell has not publicly commented on whether he will do so or not. Additionally, many legal commentators reportedly expect the U.S. Supreme Court to rule against the Trump administration in the lawsuit over the attempted removal of Federal Reserve Governor Lisa Cook in light of a ruling the Court issued the previous year and the oral arguments the Court held on January 21, 2026.
=== Biomaterials and Tissue Engineering === This program develops carriers for drug delivery and tissue regeneration scaffolds. Research combines polymer chemistry, stem cell differentiation, and 3D bioprinting to create vascular grafts, bone/cartilage replacements, and neural matrices. Studies explore relationships between material properties and biological responses.
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.