AEDG is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-04-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four amino acid residues |
| Residue sequence | Ala-Glu-Asp-Gly | Abbreviated AEDG |
| Approximate mass | 390.35 Da | Monoisotopic, free base form |
| Parent preparation | Epithalamin extract | Derived from pineal tissue |
| Common spelling variants | Epithalon, epithalone, AEDG | Affects literature retrieval |
Discussions in the literature often conflate three distinct entities: the pineal extract epithalamin, the isolated tetrapeptide AEDG, and commercial preparations sold under similar names. Reviews citing older Russian-language studies sometimes omit detail on purity, route of administration and control groups, which makes cross-study comparison difficult. Researchers working with the compound generally note the need for independent replication, standardized enzyme assays, and clearer reporting of peptide identity. These caveats are relevant when weighing claims that appear in secondary sources rather than in primary reports.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
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In 2012, a team of researchers at the British chemical and biological defence laboratories at Porton Down found carfentanil and remifentanil in clothing from two British survivors of the 2002 Moscow theater hostage crisis and in the urine from a third survivor. The team concluded that the Russian military had used an aerosol mist of carfentanil and remifentanil to subdue Chechen hostage takers. Researchers had previously surmised from the available evidence that the Moscow emergency services had not been informed of the use of the agent, despite being instructed to bring opioid antagonists to the scene. Unaware that hundreds of patients had been exposed to high doses of strong opioids, the emergency workers failed to bring sufficient quantities of naloxone and naltrexone to counteract the effects of carfentanil and remifentanil. One hundred and twenty-five people exposed to the aerosol are confirmed to have died from respiratory failure during the incident.
Lisdexamphetamine (also known as Lisdexamfetamine Dimesylate), and sold under the brand names Vyvanse ( , VY-vans) and Elvanse among others, is a stimulant medication that is used as a treatment for attention deficit hyperactivity disorder (ADHD) in both children and adults, and for moderate-to-severe binge eating disorder in adults. A prodrug of dextroamphetamine, lisdexamphetamine is taken by mouth. Its effects generally begin within 90 minutes and last for up to 14 hours. Common side effects of lisdexamphetamine include hypertension, loss of appetite, anxiety, diarrhea, trouble sleeping, irritability, and nausea. Rare but serious side effects include mania, sudden cardiac death in those with underlying heart problems, and psychosis. It has a high potential for substance abuse. Serotonin syndrome may occur if used with certain other medications. Its use during pregnancy may result in harm to the fetus, and use during breastfeeding is not recommended by the manufacturer as dextroamphetamine (its metabolite) can pass through the breastmilk. Lisdexamphetamine is an inactive prodrug that is formed by the condensation of L-lysine, a naturally occurring amino acid, and dextroamphetamine. In the blood, peptidase enzymes reverse this process to release the active agent, the central nervous system (CNS) stimulant dextroamphetamine. Lisdexamphetamine was approved for medical use in the United States in 2007 and in the European Union in 2012. In 2023, it was the 76th most commonly prescribed medication in the United States, with more than 9 million prescriptions.
Sources: en.wikipedia.org
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Under Xi, China's official military budget has more than doubled, reaching a record $282 billion in 2026. Though predating Xi, his administration has taken a more assertive stance towards maritime affairs, and has boosted CCP control over the maritime security forces. The PLA Navy has grown rapidly under Xi, with China adding more warships, submarines, support ships and major amphibious vessels from 2014 to 2019 than the entire number of ships serving in the United Kingdom's fleet. Aircraft carriers Shandong and Fujian entered into service under Xi in 2019 and 2025 respectively. In 2017, China established the navy's first overseas base in Djibouti. Xi has also undertaken an expansion of China's nuclear arsenal, with him calling China to "establish a strong system of strategic deterrence." The Federation of American Scientists (FAS) has estimated China's total nuclear arsenal to be 600 in 2025, with the US Department of Defense estimating that China's arsenal could reach 1,000 by 2030.
Sources: en.wikipedia.org
Drive to improve quality of patient care Need to contain burgeoning healthcare costs Improve accessibility and portability of patient records Better source data for epidemiological studies Before health records can be successfully communicated and stored there must be a fundamental agreement on the definition for each individual piece of information. Terminology solutions for describing such "concepts" currently include (but are not limited to) SNOMED CT, LOINC and the NPU. Key benefits conferred by the NPU terminology include:
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Sources: en.wikipedia.org
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.
No. Epithalamin is a heterogeneous extract containing many peptides, while epitalon is a single synthesised tetrapeptide. Publications sometimes treat findings from the two as equivalent, which is a common source of confusion. Their compositions differ and they are not interchangeable in analytical terms.
Most published work uses cell cultures or rodents because those models are faster and less costly to run. The few human trials that have been reported are small, and several lack control groups or blinding. This restricts what can reasonably be concluded about effects in people.
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.