AEDG tetrapeptide 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.
Updated 2025-08-19. Numbers and descriptions here follow the published literature rather than marketing material.
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-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.
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.
| 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 |
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.
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.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
Pituitary adenylate cyclase-activating polypeptide type 1 receptor InterPro: IPR002285 PACAPR (ADCYAP1R1) Calcitonin receptor InterPro: IPR003287 CALCR Calcitonin receptor-like receptor InterPro: IPR015476 CALCRL Corticotropin-releasing hormone receptor InterPro: IPR003051 CRHR1; CRHR2 Glucose-dependent insulinotropic polypeptide receptor/Gastric inhibitory polypeptide receptor InterPro: IPR001749 GIPR Glucagon receptor InterPro: IPR003291 GCGR Glucagon receptor-related InterPro: IPR003290 GLP1R; GLP2R; Growth hormone releasing hormone receptor InterPro: IPR003288 GHRHR Parathyroid hormone receptor InterPro: IPR002170 PTHR1; PTHR2 Secretin receptor InterPro: IPR002144 SCTR Vasoactive intestinal peptide receptor InterPro: IPR001571 VIPR1; VIPR2
Watanabe et al. (2026) report evidence from the study of genomes of the Jōmon people indicative of their descent from Upper Paleolithic continental East Asian populations that settled the Japanese archipelago between 27,000 and 19,000 years ago, and evidence of cold adaptation in the Jōmon lineage. Evidence from the study of stone tool assemblages from the Buhais Rockshelter (United Arab Emirates) indicative of repeated occupation of the studied area between 210,000 and 16,000 years ago (including in the time of overall increased aridity of the Arabian Peninsula between 60,000 and 16,000 years ago) is presented by Bretzke et al. (2026). Evidence from the study of Natufian artefacts and rock art from the Sahout site and the neighbouring sites of Jebel Arnaan and Jebel Misma (Saudi Arabia), indicative of occupation of the studied area by communities interacting with people from the Fertile Crescent during the terminal Pleistocene and early Holocene, is presented by Shipton et al. (2026). Davin et al. (2026) report the discovery of clay ornaments from Natufian (late Epipalaeolithic) sites in Israel, interpreted as produced both by adults and by children, and representing the earliest known clay ornamental tradition outside of Europe. Evidence of importance of consumption of lizards and snakes in subsistence strategies of Natufian foragers from the El Wad site (Israel) is presented by Lev, Weinstein-Evron & Yeshurun (2026).
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These central and peripheral actions are associated with decreased plasma norepinephrine and reduced urinary catecholamine excretion, and with reductions in plasma renin and urinary aldosterone reported alongside decreases in total peripheral resistance and heart rate. With intravenous administration, clonidine may cause a short-lived increase in blood pressure attributed to α2 adrenoceptor-mediated vasoconstriction in vascular smooth muscle, followed by a more sustained hypotensive response once clonidine crosses the blood brain barrier and binds to its receptor sites in the medulla oblongata; this biphasic pattern is generally less evident with oral or transdermal routes of administration due to dilution of the drug before reaching circulation. In the prefrontal cortex, α2A is the predominant α2 adrenoceptor subtype, and clonidine's attention- and working memory-related effects are attributed to postsynaptic α2A activation. Across the brain more generally, α2A and α2C adrenoceptors are widely distributed, while α2B is primarily expressed in the thalamus. α2A adrenoceptors on dendritic spines of prefrontal pyramidal neurons can close hyperpolarization-activated cyclic nucleotide-gated channels (HCNs) to promote attentional control and working memory. The mechanism behind this behavioral effect has been described as the consequence of improved signal-to-noise ratio in the prefrontal cortex, which can facilitate focused attention on relevant stimuli and improved cognitive control of behavior.
Sources: en.wikipedia.org
South Africa's leading opposition party, the Democratic Alliance, launched a court application to ensure the South African government detained Vladimir Putin and hand him over to the International Criminal Court for war crimes in Ukraine should he "set foot in South Africa." The move followed speculation on whether he would attend the BRICS summit to be held in the country in August, to which the government had granted prior diplomatic immunity to all attendees.
Myiasis ( my-EYE-ə-səss), also known as flystrike or fly strike, is the parasitic infestation of the body of a live animal by fly larvae (maggots) that grow inside the host while feeding on its tissue. Although flies are most commonly attracted to open wounds and urine- or feces-soaked fur, some species (including the most common myiatic flies—the botfly, blowfly, and screwfly) can create an infestation even on unbroken skin. Non-myiatic flies (such as the common housefly) can be responsible for accidental myiasis. Because some animals (particularly non-native domestic animals) cannot react as effectively as humans to the causes and effects of myiasis, such infestations present a severe and continuing problem for livestock industries worldwide, causing severe economic losses where they are not mitigated by human action. Although typically a far greater issue for animals, myiasis is also a relatively frequent disease for humans in rural tropical regions where myiatic flies thrive, and often may require medical attention to surgically remove the parasites. Myiasis varies widely in the forms it takes and its effects on those affected. Such variations depend largely on the fly species and where the larvae are located. Some flies lay eggs in open wounds, other larvae may invade unbroken skin or enter the body through the nose or ears, and still others may be swallowed if the eggs are deposited on the lips or food. There can also be accidental myiasis that Eristalis tenax can cause in humans via water containing the larvae or in contaminated uncooked food.
Duck and Cover, a 1951 educational movie explaining what to do in the event of a nuclear attack. Five, a 1951 film about five survivors, one woman and four men, of an atomic war that has wiped out the rest of the human race (while leaving all infrastructure intact). The five come together at a remote, isolated hillside house in Southern California, where they try to figure out how to survive while also being forced to face an unknown future. On the Beach (1959) depicted a gradually dying, post-apocalyptic world in Australia that remained after a nuclear Third World War. The Mouse on the Moon (1963) a comedy satire about, the people of the Duchy of Grand Fenwick, a microstate in Europe, attempt space flight using wine as a propellant. It satirises the space race, Cold War and politics. Ladybug Ladybug (1963) an elementary school nuclear bomb warning alarm sounds. Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964) – A black comedy film that satirizes the Cold War and the threat of nuclear warfare. Fail-Safe (1964) – A film based on a novel of the same name about an American bomber crew and nuclear tensions. The War Game (BBC, 1965; aired 1985) – Depicts the effects of a nuclear war in Britain following a conventional war that escalates to nuclear war. Damnation Alley (20th Century Fox, 1977) – Surprise ICBM attack launched on the United States, and the subsequent efforts of a small band of survivors from a missile silo in the Mojave Desert in California to reach another group of survivors in Albany, New York.
=== Concrete exposed to hydrocarbon fires === Concrete cannot, by itself, withstand severe hydrocarbon fires. In the Channel Tunnel that connects the United Kingdom and France, an intense fire broke out and reduced the concrete lining in the undersea tunnel down to about 50 mm. In ordinary building fires, concrete typically achieves excellent fire-resistance ratings, unless it is too wet, which can cause it to crack and explode. For unprotected concrete, the sudden endothermic reaction of the hydrates and unbound humidity inside the concrete generates pressure high enough to spall off the concrete, which falls in small pieces on the floor of the tunnel. Humidity probes are inserted into all concrete slabs that undergo fire testing to test for this, even for the less severe building elements curve (DIN4102, ASTM E119, BS476, or ULC-S101). The need for fireproofing was demonstrated, among other fire protection measures, in the European "Eureka" Fire Tunnel Research Project, which gave rise to building codes for the trade to avoid the effects of such fires upon traffic tunnels. Cementitious spray fireproofing must be certification-listed and applied in the field as per that listing, using a hydrocarbon fire test curve such as the one used in UL1709.
On June 23, 2021, the NPR station CapRadio reported that Newsom and Cal Fire had falsely claimed in January 2020 that 90,000 acres (36,000 ha) of land at risk for wildfires had been treated with fuel breaks and prescribed burns; the actual treated area was 11,399 acres (4,613 ha), an overstatement of 690%. According to CapRadio, the fuel breaks of the 35 "priority projects" Newsom had touted, which were meant to ensure the quick evacuation of residents while preventing traffic jams and a repeat of events in the 2018 fire that destroyed the town of Paradise, where at least eight evacuees burned to death in their vehicles, were struggling to mitigate fire spread in almost every instance while failing to prevent evacuation traffic jams. The same day CapRadio revealed the oversight, leaked emails showed that Newsom's handpicked Cal Fire chief had ordered the removal of the original statement. In another report in April 2022, CapRadio found a program, hailed in 2020 by the Newsom administration to fast-track environmental reviews on high-priority fire prevention projects, had failed to make progress. KXTV released a series of reports chronicling PG&E's liabilities after committing 91 felonies in the Santa Rosa and Paradise fires. Newsom was accused of accepting campaign donations from PG&E in order to change the CPUC's ruling on PG&E's safety license. The rating change allowed PG&E to avoid billions of dollars in extra fees.
Sources: en.wikipedia.org
=== Early life === Because of his father's career as a foreign service officer, much of Platt's childhood was spent in Asia and Washington, D.C. Platt attended twelve different schools, including the American School in Japan, and has said "Even now I find myself envying people who have neighborhoods and roots." Platt's family made frequent trips back to Washington, where they held Redskins season tickets. Platt is also a fan of the Boston Red Sox. When he was nine years old, Platt and his family visited the Kennedy Center in Washington, where he watched a performance that helped inspire his acting career. "One of the performances that really made me want to be an actor started out with this probably 20-minute rambling, drunken monologue by this bum. And it was a young Morgan Freeman. I'll never forget it. This guy was just so riveting. He stood there on stage alone before the curtain went up, and he held this audience utterly rapt. Including myself, obviously." According to Platt, drama departments gave his childhood some stability, "It was something of a survival mechanism, in that it gave me a little subculture to plug into wherever I ended up. Kids need that. I certainly did."
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coding strand Also sense strand, positive (+) sense strand, and nontemplate strand. The strand of a double-stranded DNA molecule whose nucleotide sequence corresponds directly to that of the RNA transcript produced during transcription (except that thymine bases are substituted with uracil bases in the RNA molecule). Though it is not itself transcribed, the coding strand is by convention the strand used when displaying a DNA sequence because of the direct analogy between its sequence and the codons of the RNA product. Contrast template strand; see also sense.
=== Proteins and amino acids === In proteins and amino acids, the α-carbon is the backbone carbon before the carbonyl carbon atom in the molecule. Therefore, reading along the backbone of a typical protein would give a sequence of –[N—Cα—carbonyl C]n– etc. (when reading in the N to C direction). The α-carbon is where the different substituents attach to each different amino acid. That is, the groups hanging off the chain at the α-carbon are what give amino acids their diversity. These groups give the α-carbon its stereogenic properties for every amino acid except for glycine. Therefore, the α-carbon is a stereocenter for every amino acid except glycine. Glycine also does not have a β-carbon, while every other amino acid does. The α-carbon of an amino acid is significant in protein folding. When describing a protein, which is a chain of amino acids, one often approximates the location of each amino acid as the location of its α-carbon. In general, α-carbons of adjacent amino acids in a protein are about 3.8 ångströms (380 picometers) apart.
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.
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.