AEDG comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-01-12. Where a claim depends on a specific study, the study is described rather than over-claimed.
Because epitalon has no pharmacopoeial monograph, quality assessment depends on supplier documentation and independent testing. Certificates of analysis typically report a purity figure from a single chromatographic run, a measured mass and sometimes an appearance description, but methods and acceptance criteria are not harmonised across vendors. Third-party laboratories can repeat identity and purity measurements, and mismatches between labelled and measured peptide content have been described for research peptides generally. What constitutes adequate identity confirmation for a molecule of this size stays an open question, since mass agreement alone does not separate closely related sequences.
Identity testing for epitalon relies on reversed-phase high-performance liquid chromatography for purity and mass spectrometry for mass confirmation. Because the sequence contains no tryptophan or tyrosine, ultraviolet detection at 280 nanometres is insensitive, so chromatographic methods usually monitor absorbance near 214 nanometres, where the peptide backbone absorbs. Electrospray ionisation or matrix-assisted laser desorption/ionisation then checks the intact mass against the expected value near 390 daltons. Peptide mapping or amino acid analysis after acid hydrolysis can supplement these measurements, although such confirmatory work is seldom reported on commercial certificates of analysis.
Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.
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.
| Property | Value | Notes |
|---|---|---|
| Analytical method | Reversed-phase HPLC | Purity determination, typically 214 nm |
| Mass confirmation | ESI or MALDI mass spectrometry | Compared with mass near 390 Da |
| Common synonyms | Epitalon, epithalon, AEDG | Naming differs between suppliers |
| Storage temperature | −20 °C or lower | Lyophilised powder, kept desiccated |
| Solution stability | Limited in neutral aqueous buffer | Aspartimide and hydrolysis pathways |
Typical storage for the lyophilized powder is −20 °C or lower, in a sealed container protected from light and moisture. Hygroscopic material should be allowed to equilibrate to room temperature before the vial is opened, which limits condensation on the contents. Working solutions are commonly divided into single-use aliquots and frozen to avoid repeated freeze-thaw cycles. Dilute solutions are more prone to adsorption onto plastic surfaces and to loss during filtration, so procedures that minimize transfers and use low-binding labware are preferable.
Reversed-phase high-performance liquid chromatography is the standard approach for assessing purity, usually with ultraviolet detection near 214 nm, where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the molecular mass and helps reveal truncation or deletion byproducts. Amino acid analysis can verify composition, and counterion content is sometimes measured because peptides purified with trifluoroacetic acid retain variable amounts of that salt. Purity figures reported without a stated method and detection wavelength are difficult to interpret.
Material sold for research use varies widely in documented quality. A useful verification package includes a certificate of analysis that states peptide content rather than only net weight, the chromatographic method and column used, and a mass spectrum consistent with the expected mass. Independent testing by a third-party laboratory is occasionally reported. Statements of identity resting only on a supplier label provide little assurance, and the gap between nominal mass and actual peptide content can be substantial once counterions and residual water are counted.
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.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.
No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
== External links == Royal Society of Chemistry, Historical Group, short biography of Curtius University of Kiel history of the inorganic department Heidelberg University German Alpen Association, Kiel section
Cardiac muscle tissue or myocardium forms the bulk of the heart. The heart wall is a three-layered structure with a thick layer of myocardium sandwiched between the inner endocardium and the outer epicardium (also known as the visceral pericardium). The inner endocardium lines the cardiac chambers, covers the cardiac valves, and joins with the endothelium that lines the blood vessels that connect to the heart. On the outer aspect of the myocardium is the epicardium which forms part of the pericardial sac that surrounds, protects, and lubricates the heart. Within the myocardium, there are several sheets of cardiac muscle cells or cardiomyocytes. The sheets of muscle that wrap around the left ventricle closest to the endocardium are oriented perpendicularly to those closest to the epicardium. When these sheets contract in a coordinated manner they allow the ventricle to squeeze in several directions simultaneously – longitudinally (becoming shorter from apex to base), radially (becoming narrower from side to side), and with a twisting motion (similar to wringing out a damp cloth) to squeeze the maximum possible amount of blood out of the heart with each heartbeat. Contracting heart muscle uses a lot of energy, and therefore requires a constant flow of blood to provide oxygen and nutrients. Blood is brought to the myocardium by the coronary arteries. These originate from the aortic root and lie on the outer or epicardial surface of the heart. Blood is then drained away by the coronary veins into the right atrium.
Zakharyan RA, Aposhian HV (1999). "Enzymatic reduction of arsenic compounds in mammalian systems: the rate-limiting enzyme of rabbit liver arsenic biotransformation is MMA(V) reductase". Chem. Res. Toxicol. 12 (12): 1278–83. doi:10.1021/tx9901231. PMID 10604879.
In 1147, Roger II attacked Corinth and Thebes, two important centers of Byzantine silk production, capturing the weavers and their equipment and establishing his own silkworks in Calabria, thereby allowing the Norman silk industry to flourish. In 1194, Frederick II took control of the region, after inheriting the Kingdom from his mother Constance, Queen of Sicily. He created a kingdom that blended cultures, philosophy and customs and built several castles, while fortifying existing ones that the Normans had previously constructed. After the death of Frederick II in 1250, Calabria was controlled by the Capetian House of Anjou, under Charles d’Anjou after he was granted the crown of the Sicilian Kingdom by Pope Clement IV. In 1282, under Charles d’Anjou, Calabria became a domain of the newly created Kingdom of Naples, and no longer of the Kingdom of Sicily, after he lost Sicily due to the rebellion of the Sicilian Vespers. During the 14th century, Barlaam of Seminara who became Petrarch's Greek teacher and his disciple Leonzio Pilato, who translated Homer's works for Giovanni Boccaccio. While the cultivation of mulberry was beginning in northern Italy, silk made in Calabria peaked at 50% of European production. As the cultivation of mulberry was difficult in Northern and Continental Europe, merchants and operators used to purchase raw materials in Calabria. The Genoese silk artisans used fine Calabrian silk for the production of velvets.
Greenland is an autonomous territory of the Kingdom of Denmark, and has been associated with the Scandinavian kingdoms of Denmark and Norway for more than a millennium, beginning in 986 AD when Norse settlers from what is now Norway and Iceland settled Greenland. The 13th century saw the arrival of the Inuit, the ancestors of today's majority population. After around 400 years, the Norse settlement in Greenland is believed to have died out in the late 15th century, but the legends of it persisted in Scandinavia. This prompted King Christian IV to send an expedition to Greenland in 1605 to locate the lost Eastern Norse Settlement and reassert sovereignty over Greenland. Norwegian priest Hans Egede reestablished a permanent Dano-Norwegian presence in 1721, founding the town of Godthaab (now Nuuk). Today's population is mainly Inuit, with a smaller Danish population, and many people are of mixed Inuit and Danish origin. Greenlanders often have close family, personal, and cultural ties to Denmark, with thousands living there. Greenland formally became part of the Kingdom of Norway in 1261, when the Norse inhabitants submitted to the King of Norway. Norway then entered a union with Denmark in 1380. Under the 1814 Treaty of Kiel, Greenland remained with the Danish Crown as part of the settlement with Sweden following the Napoleonic Wars. Denmark declared full sovereignty over all of Greenland, including the uninhabited parts, in 1921, in the aftermath of the Treaty of Versailles.
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Sturm, Marc; Bertsch, Andreas; Gröpl, Clemens; Hildebrandt, Andreas; Hussong, Rene; Lange, Eva; Pfeifer, Nico; Schulz-Trieglaff, Ole; Zerck, Alexandra; Reinert, Knut; Kohlbacher, Oliver (December 2008). "OpenMS – An open-source software framework for mass spectrometry". BMC Bioinformatics. 9 (1): 163. doi:10.1186/1471-2105-9-163. PMC 2311306. PMID 18366760. Kohlbacher, O.; Reinert, K.; Gropl, C.; Lange, E.; Pfeifer, N.; Schulz-Trieglaff, O.; Sturm, M. (15 January 2007). "TOPP--the OpenMS proteomics pipeline". Bioinformatics. 23 (2): e191–e197. doi:10.1093/bioinformatics/btl299. PMID 17237091.
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The G protein-coupled receptor kinases (GRKs) are protein kinases that phosphorylate only active GPCRs. G-protein-coupled receptor kinases (GRKs) are key modulators of G-protein-coupled receptor (GPCR) signaling. They constitute a family of seven mammalian serine-threonine protein kinases that phosphorylate agonist-bound receptor. GRKs-mediated receptor phosphorylation rapidly initiates profound impairment of receptor signaling and desensitization. Activity of GRKs and subcellular targeting is tightly regulated by interaction with receptor domains, G protein subunits, lipids, anchoring proteins and calcium-sensitive proteins. Phosphorylation of the receptor can have two consequences:
3-Dehydrocarnitine is an aliphatic quaternary ammonium betaine that is part of the carnitine family. At physiological pH of 7.3, the major species of 3-dehydrocarnitine is its zwitterionic form, the conjugate base of 3-dehydrocarnitinium. 3-Dehydrocarnitine is classified as a short-chain keto acid, as it has a carbon chain containing less than six carbon atoms. It is an intermediate in carnitine degradation and is formed from D- or L-carnitine. The enzymes responsible for the degradation of carnitine to 3-dehydrocarnitine are carnitine-3-dehydrogenase or (S)-carnitine-3-dehydrogenase.
=== Application === Some fission products (such as 137Cs) are used in medical and industrial radioactive sources. 99TcO4− (pertechnetate) ion can react with steel surfaces to form a corrosion resistant layer. In this way these metaloxo anions act as anodic corrosion inhibitors - it renders the steel surface passive. The formation of 99TcO2 on steel surfaces is one effect which will retard the release of 99Tc from nuclear waste drums and nuclear equipment which has become lost prior to decontamination (e.g. nuclear submarine reactors which have been lost at sea). In a similar way the release of radio-iodine in a serious power reactor accident could be retarded by adsorption on metal surfaces within the nuclear plant. Much of the other work on the iodine chemistry which would occur during a bad accident has been done.
Sources: en.wikipedia.org
== In cardiovascular diseases == HSP70 is a chaperone with ubiquitous presence. It is crucial in the cardiovascular system. HSP70 normally aids in protein folding and aggregation; when present in the cell, functioning as an anti-inflammatory molecule; however, under stress conditions, it occurs in the extracellular milieu, where it is involved in inducing inflammatory pathways and contributes to disease pathogenesis. It is well established that intracellular HSP70 (iHSP70) levels play a protective role, whereas extracellular HSP70 (eHSP70) levels in circulating blood are linked to pathophysiology in vasculature, which results in a variety of cardiovascular illnesses. HSP70 homologues identified in human cytosol includes HSPA1A, HSPA1B, HSPA1L, HSPA12B, HSPA13, HSPA14 whereas HSPA9 in mitochondria. HSP70 acts as a damage-associated molecular pattern (DAMP) and activates innate immune response, which is involved in cardiovascular disease progression. The chaperone protein acts as auto antigen in atherosclerosis. Increased oxidative stress causes the formation of high-density oxidized LDL, the first event in the formation of plaque. This activates HSP70 and its promoter in the endothelial and smooth muscle cells, which contributes to atherosclerosis by inducing JAK/STAT pathway expression. HSP70 is linked to high blood pressure. HSPA1A, HSPA1B, and HSPA1L are three genes in humans that encode HSP70, and their polymorphism is linked to the onset of high blood pressure and cardiovascular disease.
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=== Fortification === The World Health Organization does not have any recommendations for food fortification with vitamin E. The Food Fortification Initiative does not list any countries that have mandatory or voluntary programs for vitamin E. Infant formulas have alpha-tocopherol as an ingredient. In some countries, certain brands of ready-to-eat cereals, liquid nutrition products, and other foods have alpha-tocopherol as an added ingredient.
==== Member of the Order of the British Empire (MBE) ==== Civil Division Inspector Joe Arukai. For services to the Royal Papua New Guinea Constabulary. Sister Joseph Mary Cresp. For services to charity. Bamaga Morre Imari. For services to the community, public service and the government. Justin Hansu Kill. For services to broadcasting. Sally Mokis. For services to the Papua New Guinea Banking Corporation. Membup Paril. For public services and services to the community. Cecilia Ropa. For services to health and the community. Noki Timbil. For services to the community.
=== 2025 Pahalgam Rescue Operation === At the time of Pahalgam terror attack April 2025, Santosh Lad was instructed to reach Kashmir and rescue people of Karnataka over three intense days, he coordinated the safe return of 177 Kannadigas from different parts of Kashmir.
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The molecule lacks aromatic residues, so it absorbs weakly near 280 nanometres, the wavelength applied to many other peptides. The peptide bond absorbs strongly below 220 nanometres, making 214 nanometres a practical compromise. Gradient methods must therefore use mobile phases with low ultraviolet absorbance to keep the baseline clean.
Neutral and slightly basic aqueous conditions promote aspartimide formation at the aspartate-glycine step, often followed by deamidation. Elevated temperature and repeated freeze-thaw cycles accelerate the loss. Acidic solutions and dry lyophilised powder are comparatively stable over short periods.
No monograph exists in the United States Pharmacopeia or the European Pharmacopoeia, and no widely distributed certified reference standard is available. Purity and identity therefore rest on supplier methods that are not harmonised. This absence is the main reason reported purities are difficult to compare between sources.
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.