If you have been reading about AEDG and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-01-12. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Linear tetrapeptide, also written AEDG |
| Molecular mass | About 390.35 g/mol | Value calculated from the sequence |
| Appearance | White to off-white powder | Lyophilised material forms a loose cake |
| Solubility | Freely soluble in water | Also dissolves in isotonic saline |
| Storage | -20 °C, desiccated | Aliquot solutions to avoid freeze–thaw cycling |
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.
=== February === 1 February – An estimated 475,000 workers go on strike, the single biggest day of industrial action for more than a decade, in disputes over pay and conditions. This includes 200,000 teachers, 100,000 civil servants including border force workers, university lecturers, security guards, and train drivers. The government warns the public to expect "significant disruption". 2 February The Bank of England raises its key interest rate from 3.5 to 4%, the highest level in 14 years. The energy regulator Ofgem asks energy companies to suspend the forced installation of prepayment meters following an investigation by The Times which showed agents working for British Gas breaking into the homes of vulnerable customers to install the meters. 3 February Gary Glitter is freed from prison after serving half of a 16-year jail term for attempted rape, four counts of indecent assault and one of having sex with a girl under 13. COVID-19 in the UK: Office for National Statistics data for the week up to 24 January indicates that COVID-19 cases continue to fall, with an estimated 1 in 70 people (1.42% of the population) testing positive for the virus in England over that time. 5 February Emma Pattinson, the head of Epsom College in Surrey, is found dead along with her husband and seven-year-old daughter in a property at the school. Police suspect a murder-suicide by gunshot.
==== 1998 congressional campaign ==== In 1998, Yates opted to forgo reelection, and Pritzker ran in the Democratic primary to succeed him, reconstituting his campaign committee in April 1997. Also running in the primary were state representative Jan Schakowsky and state senator Howard W. Carroll. The district covered the northern lakefront of Chicago, as well as the suburbs of Evanston and Skokie. It had a large Jewish electorate and had long been regarded as the "Jewish seat" in Illinois's congressional delegation. Yates was Jewish, as were all three Democratic contenders to succeed him. The district had been described as being among the most liberal in the country. Journalist James Ylisela Jr. observed that Pritzker, Schakowsky, and Carroll largely all ran on platforms aligned with the "liberal Democratic Party agenda" that Yates had championed. But the Chicago Tribune wrote that Pritzker and Carroll ran on more moderate platforms than Schakowsky, and therefore potentially wound up competing with each other for many of the same voters. At the time, the election was one of the most expensive congressional primaries in U.S. history, and Pritzker spent nearly $1 million of his own money on his campaign. This included $500,000 on television ads in the Chicago market. He finished third among five candidates in the Democratic primary, with 20.5% of the vote to Schakowsky's 45.1% and Carroll's 34.4%. Schakowsky went on to represent the district for 28 years, retiring after the 2026 election.
But it did get a little close there for a while. As you may know, there were 61 planes in the air headed toward Haïti at the time they finally agreed. And at one point General Biamby came in and told General Cédras that he had just gotten word on his telephone that the airplanes had taken off from Pope Air Force Base, with soldiers from Fort Bragg, and that both disconcerted them and caused them to be suspicious of the intent of the negotiations, but it also created a situation where immediately after that, the key points they had been refusing to agree to were agreed to, a date certain, other matters that I won't go into in detail here.
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Due to the rapid increase in COVID-19 cases across the country, the CBSE cancelled the 10th class board exams and postponed the 12th class exams. Like the 10th, Class 12th Board Exam 2021 has also been cancelled. Prime Minister Narendra Modi decided on this after a long meeting on 1 June 2021. Later, in a letter dated 5 July 2021, CBSE announced a special assessment scheme for the board examinations of classes X and XII for the session 2021–22. The academic year was divided into two terms, with approximately 50% of the syllabus in each, to increase the likelihood that the CBSE would conduct boards and avoid relying on schools to declare results. The Term 1 examination was successfully conducted by CBSE in objective mode from 22 November to 12 December 2021 for Class 10 and from 16 November to 30 December 2021 for Class 12. However, the Term-I examination was criticised by many for having wrong answer keys, tough question papers and wrong or controversial questions, with a question being dropped in Sociology exam of class 12 and a paragraph in the English Language and Literature exam for class 10 by CBSE following which CBSE dropped the experts who set the Sociology and English paper from paper-setting panels. The Term 2 examination was conducted from 26 April 2022 for both Class 10 and 12 and ended on 24 May for Class 10 and 15 June for Class 12. The Class 12 results were declared on 22 July 2022, followed by Class 10 results on the same day.
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γ-L-Glutamyl-L-cysteine, also known as γ-glutamylcysteine (GGC), is a dipeptide found in animals, plants, fungi, some bacteria, and archaea. It has a relatively unusual γ-bond between the constituent amino acids, L-glutamic acid and L-cysteine and is a key intermediate in the γ-glutamyl cycle first described by Meister in the 1970s. It is the most immediate precursor to the antioxidant glutathione.
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Administratively, Le Havre is a commune in the Normandy region in the west of the department of Seine-Maritime. The urban area of Le Havre corresponds roughly to the territory of the Agglomeration community of Le Havre (CODAH) which includes 17 communes and 250,000 people. It occupies the south-western tip of the natural region of Pays de Caux where it is the largest city. Le Havre is sandwiched between the coast of the Channel from south-west to north-west and the estuary of the Seine to the south.
Regional tectonic processes affected mainland Portugal's morphostructural units differently, producing relief variations that subdivide the territory into ten regional geomorphological units. These units were shaped by the differing regional impacts of Cenozoic tectonics, climatic asymmetries in the Paleogene, Neogene, and Quaternary, and varied lithological responses to tectonic activity and climatic variability. Continental Portugal is predominantly low-altitude, with over 70% of the territory lying below 400 m (1,300 ft) and less than 12% rising above 700 m (2,300 ft) of elevation. Its geography is structured by the Tagus River, which enters from Spain and flows into the Tagus Estuary, as 95% of areas exceeding 400 m (1,300 ft) are situated to the north of the river while the regions south of the Tagus, encompassing Alentejo and the Algarve, have 62% of the lands below 200 m (660 ft). The territory north of the Tagus is marked by mountains and plateaus incised by river valleys, whereas the south is distinguished by rolling plains. The Madeira archipelago comprises the islands of Madeira and Porto Santo, together with the Desertas and Savage Islands, all of which are of volcanic origin. Approximately one-third of Madeira Island lies above 1,000 metres (3,300 ft) in elevation, and its landscape is characterised by a dense network of deep valleys with slopes rising several hundred metres, as well as streams that originate in the island's centre and diverge towards the coast, sustained by abundant rainfall.
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By 15 January 1919, Poles had taken control of most of the province, and they engaged in heavy fighting with the regular German army and irregular units such as the Grenzschutz Ost. Fighting continued until the renewal of the truce between the Entente and Germany on 16 February. The truce also affected the front line in Greater Poland, but despite the ceasefire, skirmishes continued until the final signing of the Treaty of Versailles on 28 June 1919. The uprising is one of the two most successful Polish uprisings, the other being the Great Poland uprising of 1806, which ended with the entry of Napoleon's army on the side of the Poles fighting against Prussia. Many of the Greater Poland insurrectionists later took part in the Silesian Uprisings against German rule, which started in late 1919 and ended in 1921.
The laboratory analysis of homocysteine itself is complicated because most homocysteine (possibly above 85%) is bound to other thiol amino acids and proteins in the form of disulphides (e.g., cysteine in cystine-homocysteine, homocysteine in homocysteine-homocysteine) via disulfide bonds. Since as an equilibrium process the proportion of free homocysteine is variable a true value of total homocysteine (free + bound) is useful for confirming diagnosis and particularly for monitoring of treatment efficacy. To this end it is prudent to perform total homocyst(e)ine analysis in which all disulphide bonds are subject to reduction prior to analysis, traditionally by HPLC after derivatisation with a fluorescent agent, thus giving a true reflection of the quantity of homocysteine in a plasma sample.
Sources: en.wikipedia.org
It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.
AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.
Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.
It is a synthetic tetrapeptide built from alanine, glutamate, aspartate and glycine. The four residues are joined by standard peptide bonds, giving a linear chain rather than a branched structure.