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 2026-06-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Derived from the four constituent residues |
| Molecular mass | About 390.35 Da | Monoisotopic value, confirmed by mass spectrometry |
| Residue sequence | Ala-Glu-Asp-Gly | Read from the N-terminus to the C-terminus |
| Common synonyms | Epithalon; AEDG | Both forms appear in reference catalogues |
| Net charge near neutral pH | Negative | Two acidic side chains give a low isoelectric point |
Fluid dynamics is a subdiscipline of fluid mechanics that deals with fluid flow—the science of liquids and gases in motion. Fluid dynamics offers a systematic structure—which underlies these practical disciplines—that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems. The solution to a fluid dynamics problem typically involves calculating various properties of the fluid, such as velocity, pressure, density, and temperature, as functions of space and time. It has several subdisciplines itself, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting evolving weather patterns, understanding nebulae in interstellar space and modeling explosions. Some fluid-dynamical principles are used in traffic engineering and crowd dynamics.
== Therapeutic application == Thymosin α1 is approved in some countries for the treatment of Hepatitis B and C, and it is also used to boost the immune response in the treatment of other diseases. The synthetic version of Thymosin α1 is known as Thymalfasin and is sold under the brand name Zadaxin. Thymosin α1 is usually administered by subcutaneous injection.
=== Video games === The Persona series of games is heavily based on Jung's theories, representing the shadow, the persona, and archetype. The Nights into Dreams series of games is heavily based on Jung's theories. Jungian concepts are present in the Xeno series, including Xenogears; its reimagination as the Xenosaga trilogy; and a graphic novel, Perfect Works, published by the game's creator. The game Control is heavily influenced by Carl Jung's ideas, particularly synchronicity and shadow selves. Alan Wake takes inspiration from Carl Jung's ideas of archetype and individuation.
=== Hurdles === Given the uneven distribution of vaccines across jurisdictions, granting privileges based on vaccination status certification means that those with easier vaccine access have unfair access to those privileges. If vaccination status is only verifiable using digital technology, those without that technology may also lose access even if they are vaccinated. Such privileging mechanisms may exacerbate inequality, increase risks of deliberate infections or transmission, Public health justifications for restricting behavior based on vaccine status have become less frequent over the course of the pandemic as vaccines do not stop transmission.
Keratotomies are a group of corneal procedures. Radial keratotomy is a refractive surgery procedure where the surgeon makes a spoke-like pattern of incisions into the cornea to modify its shape. This early surgical option for myopia has been largely superseded by PRK, LASIK and other similar laser procedures. Laser surgery is usually contraindicated in keratoconus and other corneal thinning conditions, as removal of corneal stromal tissue will further damage an already thin and weak cornea. For similar reasons, radial keratotomy has also generally not been used for people with keratoconus. However, more modern and keratoconus-specific variants, such as Mini asymmetric radial keratotomy (MARK) and Circular keratotomy (CK), have been found to be useful in keratoconus management, particularly when combined with Corneal cross-linking.
Sources: en.wikipedia.org
== Epidemiology == Acanthosis nigricans is reported worldwide, with prevalence varying by age, ethnicity and underlying metabolic risk. In clinic- and community-based samples of people with obesity and insulin resistance, reported prevalence ranges from about 7% to over 70%, depending on the population and diagnostic criteria used. Higher rates are consistently observed among individuals of African, Hispanic/Latino, Native American and some Asian ancestries, reflecting both genetic susceptibility and a higher burden of obesity and metabolic syndrome in many of these populations. In children and adolescents, the prevalence of acanthosis nigricans has risen alongside increasing rates of overweight and obesity and is common in pediatric cohorts with insulin resistance or metabolic syndrome. Across studies, acanthosis nigricans is more frequent among people with higher body mass index, increased waist circumference and biochemical markers of insulin resistance.
Copper proteins have diverse roles in biological electron transport and oxygen transportation, processes that exploit the easy interconversion of Cu(I) and Cu(II). Copper is essential in the aerobic respiration of all eukaryotes. In mitochondria, it is found in cytochrome c oxidase, which is the last protein in oxidative phosphorylation. Cytochrome c oxidase is the protein that binds the O2 between a copper and an iron; the protein transfers four electrons to the O2 molecule to reduce it to two molecules of water. Copper is also found in many superoxide dismutases, proteins that catalyze the decomposition of superoxides by converting it (by disproportionation) to oxygen or hydrogen peroxide:
BrightStarSound.com Stanislav Petrov tribute website, multiple pages with photos and reprints of various articles about Petrov Nuclear War: Minuteman Article from Weekendavisen, 2 April 2004. The Nuclear War that Almost Happened in 1983 (posted September 5, 2003). History News Network, Originally in the Baltimore Sun of 31 August 2003 Armageddon Almost Not Averted "Sept. 26, 1983: The Man Who Saved the World by Doing ... Nothing". 30 years on: The day a computer glitch nearly caused World War III. The Register. 27 September 2013
=== Effects in males === FSH stimulates primary spermatocytes to undergo the first division of meiosis, to form secondary spermatocytes. FSH enhances the production of androgen-binding protein by the Sertoli cells of the testes by binding to FSH receptors on their basolateral membranes, and is critical for the initiation of spermatogenesis.
Sources: en.wikipedia.org
CBC (may demonstrate an elevated white blood count) ESR (elevated) Perinuclear pattern of antineutrophil cytoplasmic antibodies (p-ANCA) - not associated with "classic" polyarteritis nodosa, but is present in a form of the disease affecting smaller blood vessels, known as microscopic polyangiitis or leukocytoclastic angiitis Tissue biopsy (reveals inflammation in small arteries, called arteritis) Elevated C-reactive protein A patient is said to have polyarteritis nodosa if he or she has three of the 10 signs known as the 1990 American College of Rheumatology (ACR) criteria, when a radiographic or pathological diagnosis of vasculitis is made:
Spermidine has also been found to "upregulate expression of the epithelial stem cell-associated keratins K15 and K19, and dose-dependently modulated K15 promoter activity in situ and the colony forming efficiency, proliferation and K15 expression of isolated human K15-GFP+ cells in vitro."
=== Hydride source === Formic acid shares some of the reducing properties of aldehydes, reducing solutions of metal oxides to their respective metal, and sulfur dioxide to thiosulfate via dithionite. In synthetic organic chemistry, it is often used as a source of hydride ion, as in the Eschweiler–Clarke reaction:
Sources: en.wikipedia.org
It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.
No. The two spellings refer to the same tetrapeptide, and the difference reflects transliteration from Russian. Laboratories and catalogues use both forms interchangeably. The material is also indexed as AEDG, taken from the one-letter codes of its residues.
Epithalamin is a mixed preparation derived from animal pineal tissue and contains many peptides. Epitalon is one synthetic sequence chosen for study from that broader mixture. Statements about one do not transfer directly to the other.
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.