The short version of AEDG fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-29 and is reviewed periodically as new material appears.
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.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography with ultraviolet detection, frequently near 214 nanometers where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the observed molecular mass and helps separate the intact peptide from truncated or modified forms. Amino acid analysis or tandem mass spectrometry can establish residue order. Purity is commonly quoted as an area percentage, yet such values are method-dependent, and comparisons between laboratories require matching column, gradient and detection wavelength.
Laboratory handling begins with dissolution of the lyophilized powder in water or a suitable aqueous buffer. The dry solid is the more stable form, so stock solutions are generally prepared only when required and kept cold afterwards. Repeated freezing and thawing of a solution is avoided because it encourages aggregation and gradual loss of the intact chain. Diluents and containers are selected to limit adsorption of a short peptide onto plastic surfaces and to reduce microbial growth in aqueous preparations.
Stability depends strongly on pH, temperature and the presence of oxygen and trace metals. Cleavage of the backbone proceeds faster under neutral to alkaline conditions, whereas acidic solutions tend to slow that reaction. The aspartate and glutamate side chains can undergo deamidation or imide formation over time, generating closely related impurities. Published stability data specific to epitalon are sparse, so the usable life of a given solution is best regarded as an open question that depends on buffer composition, concentration and storage temperature.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Ala-Glu-Asp-Gly | Often abbreviated AEDG in research literature |
| Common synonyms | Epithalon, epitalon, AEDG | Spelling variants refer to the same tetrapeptide |
| Molecular formula | C14H22N4O9 | Theoretical monoisotopic mass near 390.35 Da |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility class | Freely soluble in water | Hydrophilic peptide; dissolves in aqueous buffer |
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.
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.
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.
（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.
=== 1975 leadership election === Heseltine had lost faith in Heath over the second miners' strike and over Heath's personal abrasiveness (Heath had apparently once told him to his face that he was too openly ambitious); his patron Peter Walker had also come to have similar doubts about Heath. Ten days before the October 1974 election, at which Heseltine bucked the national swing by increasing his majority at Henley, he urged Heath to consider his position by the end of the year. It is unclear how Heseltine voted in the first ballot of the 1975 Conservative leadership election, in which the challenger Margaret Thatcher defeated Heath. Norman Tebbit stated that he and John Nott persuaded him to vote for Thatcher so as to open up the way for his preferred candidate Willie Whitelaw to stand on the second ballot. Another (anonymous) close friend later told Michael Crick that Heseltine voted for Thatcher. The Thatcher team had him down as an abstainer, while he refused at the time to reveal how he voted. In his memoirs Heseltine wrote that he abstained in the first ballot, but that he would have voted for Whitelaw in the first ballot had he stood against Heath. Whitelaw admired his drive and energy but looked down on him as "new Money" and is said to have commented that Heseltine was "the sort of man who combs his hair in public". Heseltine toyed with standing himself for the second ballot (in Crick's view his vote would very likely have been derisory), but voted for Whitelaw.
=== Traumatic brain injury === Repetitive mild traumatic brain injury (TBI) is a central component of contact sports, especially American football, and the concussive force of military blasts. It can lead to chronic traumatic encephalopathy (CTE), a condition characterized by fibrillar tangles of hyperphosphorylated tau. After severe traumatic brain injury, high levels of tau protein in extracellular fluid in the brain are linked to poor outcomes.
Moxonidine (INN) is an imidazoline receptor agonist antihypertensive drug licensed for the treatment of mild to moderate essential hypertension. It may have a role when thiazides, beta-blockers, ACE inhibitors, and calcium channel blockers are not appropriate or have failed to control blood pressure. In addition, it demonstrates favourable effects on parameters of the insulin resistance syndrome, apparently independent of blood pressure reduction. It is also a growth hormone releaser. It is manufactured by Solvay Pharmaceuticals (acquired by Abbott in 2009) under the brand name Physiotens and Moxon.
=== Secretary-General === The head of the OECD Secretariat and chair of the OECD Council is the Secretary-General. Secretary-General selections are made by consensus, meaning all member states must agree on a candidate.
Cupping (拔罐; báguàn) is a type of Chinese massage, consisting of placing several glass "cups" (open spheres) on the body. A match is lit and placed inside the cup and then removed before placing the cup against the skin. As the air in the cup is heated, it expands, and after placing in the skin, cools, creating lower pressure inside the cup that allows the cup to stick to the skin via suction. When combined with massage oil, the cups can be slid around the back, offering "reverse-pressure massage".
Sources: en.wikipedia.org
He was less successful militarily: an invasion of Sicily was decisively defeated by King William I in 1156, leading to tensions with Frederick Barbarossa, the Holy Roman Emperor; two decades later, an invasion of Anatolia was defeated at the Battle of Myriokephalon.
=== Role in cell adhesion, extravasation, migration === Acting through several integrins and probably a few yet unknown other receptors Thy-1 mediates adhesion of leukocytes and monocytes to endothelial cells and fibroblasts, melanoma cells to endothelium, and thymocytes to thymic epithelium. Thy1 expression comes on when endothelial cells are activated. It has been shown to interact with the leukocyte integrin Mac1 (CD11b/CD18) and may play a role in leukocyte homing and recruitment.
== Current status == Many exogenous agents have been developed since the discovery of 5-HT2C receptors. Thus far a small number of agonists, with sufficient selectivity for the 5-HT2C receptors over the other subtypes have been studied in clinical trials. A variety of other 5-HT2C receptor agonists remain in preclinical development, including Ro60-0175, WAY-163,909, and the inverse agonist SB-243,213. Evidence supports a therapeutic potential of 5-HT2C receptor modulation in the treatment of a variety of pathological conditions, including schizophrenia, obesity, urinary incontinence and sexual dysfunction.
To convert this to the real range on the ground, the plotter used basic trigonometry on a right angle triangle; the slant range was the hypotenuse and the open angle was the measurement from the radiogoniometer. The base and opposite sides could then be calculated, revealing the distance and altitude. An important correction was the curvature of the Earth, which became significant at the ranges CH worked at. Once calculated, this allowed the range to be properly plotted, revealing the grid square for the target, which was then reported up the chain. When the target was first detected at long range, the signal typically did not have enough of a return in the second lobe to perform height finding. This only became possible as the aircraft approached the station. Eventually this problem would recur as the target centred itself in the second lobe, and so forth. Additionally, it was not possible to determine the difference between a signal being compared between the first and second or second and third lobe, which caused some ambiguity at short ranges. However, as the altitude was likely determined long before this, this tended not to be a problem in practice. This pattern left a set of distinct angles where reception in both lobes was very low. To address this, a second set of receiver antennas was installed at 45 feet (14 m). When the lower antennas were used, the pattern was shifted upward, providing strong reception in the "gaps", at the cost of diminished long-range reception due to the higher angles.
Sources: en.wikipedia.org
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine–glutamate–aspartate–glycine, also written AEDG. It was developed in Russian gerontology research and is studied for proposed effects on telomerase, melatonin regulation, and neuroendocrine function. It is not an approved pharmaceutical in the United States or the European Union.
No. Epithalamin is a peptide-rich extract prepared from bovine pineal glands, while epitalon is a short synthetic peptide designed as a defined analogue of it. The synthetic version was intended to provide a reproducible molecule with some of the same proposed biological activity.
Telomere elongation and telomerase activation have been reported in cultured human somatic cells, but evidence from living human subjects is limited and has not been independently confirmed at scale. Reported findings come largely from small studies with differing designs, so the question remains open rather than settled.
The dry powder is typically held at -20 degrees Celsius or lower, protected from light and moisture. Allowing a sealed vial to reach room temperature before opening reduces condensation on its contents. Conditions stated on a supplier certificate of analysis take precedence over general guidance.