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 2025-08-30. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
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.
| 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 |
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
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.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
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.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
=== As a refrigerant === Sulfur dioxide was one of the earliest refrigerants adopted for mechanical refrigeration owing to its ease of liquefaction and high latent heat of vaporization. In 1784, Jean-François Clouet and Gaspard Monge first demonstrated that sulfur dioxide gas could be liquefied at low temperatures. In the mid-1870s, Raoul Pictet successfully employed sulfur dioxide in a prototype refrigeration system. Beginning in 1920, it saw widespread use in the "Rollator" rotary-compressor home refrigerators produced by Norge. Following the introduction of less toxic, non-flammable chlorofluorocarbon (CFC) refrigerants, the use of sulfur dioxide in refrigeration systems gradually declined.
In August 2003, Domino's announced its first new pizza since January 2000, the "Philly Cheese Steak Pizza". The product launch also marked the beginning of a partnership with the National Cattlemen's Beef Association, whose beef Check-Off logo appeared in related advertising. Domino's continued its move toward specialty pizzas in 2006, with the introduction of its "Brooklyn Style Pizza", featuring a thinner crust, cornmeal baked in to add crispness, and larger slices that could be folded in the style of traditional New York-style pizza.In 2008, Domino's once again branched out into non-pizza fare, offering oven-baked sandwiches in four styles, intended to compete with Subway's toasted submarine sandwiches. Early marketing for the sandwiches made varied references to its competition, such as offering free sandwiches to customers named "Jared", a reference to Subway's spokesman of the same name. The company introduced its "American Legends" line of specialty pizzas in 2009, featuring 40% more cheese than the company's regular pizzas, along with a greater variety of toppings. That same year, Domino's began selling its "BreadBowl Pasta" entree, a lightly seasoned bread bowl baked with pasta inside, and the "Lava Crunch Cake" dessert, a crunchy chocolate shell filled with warm fudge. Domino's promoted the dessert by flying in 1,000 cakes to deliver at Hoffstadt Bluffs Visitor Center near Mount St. Helens in Washington state.
== Promotion == In March 2006, it was announced that "Come What May," would be released on July 18, 2006. However, the release date for the album was pushed back until August 22. Because of the delay, Stone Sour released a music video for the track "Reborn", which had footage of the band working on the album in the studio. The album's cover artwork was released online on May 20, 2006. Shortly after, it was confirmed by a representative from the band's record label, Roadrunner, that the release date had been brought forward, and the official release date would be August 1, 2006. On July 31, 2006, the day before its release the album was made available online for streaming in its entirety through AOL. On May 22, 2006, the first single from the album, "30/30-150", was made available online as a free MP3 download. A music video for the single was shot with director P.R. Brown in Los Angeles and received a premier on MTV's Headbangers Ball on June 3, 2006. Prior to the release of the second single from the album, "Through Glass", radio stations throughout the US showed high support for the song. A music video for the single was shot with director Tony Petrossian and was released online on June 9, 2006, through Yahoo!. The third single from the album, "Sillyworld", began receiving radio airplay in November 2006. A music video for the single was shot in January 2007 and was released online on March 8, 2007. The fourth single from the album, "Made of Scars", had a music video which was recorded live on April 7, 2007, and was posted online on June 5, 2007.
The International System of Units (SI) unit of radioactive activity is the becquerel (Bq), named in honor of the scientist Henri Becquerel. One Bq is defined as one transformation (or decay or disintegration) per second. An older unit of radioactivity is the curie, Ci, which was originally defined as "the quantity or mass of radium emanation in equilibrium with one gram of radium (element)". Today, the curie is defined as 3.7×1010 disintegrations per second, so that 1 curie (Ci) = 3.7×1010 Bq. For radiological protection purposes, although the United States Nuclear Regulatory Commission permits the use of the unit curie alongside SI units, the European Union European units of measurement directives required that its use for "public health ... purposes" be phased out by 31 December 1985. Absorbed dose is measured in grays (Gy), while equivalent and effective doses are expressed in sieverts (Sv).
Sources: en.wikipedia.org
Allosteric activation by glucose-6-phosphate, which acts as an effector, stimulates glycogen synthase, and glucose-6-phosphate may inhibit the phosphorylation of glycogen synthase by cyclic AMP-stimulated protein kinase.
== Size exclusion chromatography == A study was done looking at the application of size exclusion chromatography in the purification of cross-link peptides within samples. When the eluted peptides were analyzed, cross-linked peptides could be detected at higher concentrations in the earlier fractions, eluting before modified or unmodified peptides.
In addition to the primary methods above, another method exists to measure the moisture content of wood: an electronic moisture meter. Pin and pinless meters are the two main types of moisture meters. Pin meters require driving two pins into the surface of the wood while making sure that the pins are aligned with the grain and not perpendicular to it. Pin meters provide moisture content readings by measuring the resistance in the electrical current between the two pins. The drier the wood, the more resistance to the electrical current, when measuring below the fiber saturation point of wood. Pin meters are generally preferred when there is no flat surface of the wood available to measure Pinless meters emit an electromagnetic signal into the wood to provide readings of the wood's moisture content and are generally preferred when damage to the wood's surface is unacceptable or when a high volume of readings or greater ease of use is required.
The highest dose of a drug or treatment that does not cause unacceptable side effects. The maximum tolerated dose is determined in clinical trials by testing increasing doses on different groups of people until the highest dose with acceptable side effects is found. Also called MTD. (NCI) Medication
==== Carbohydrates ==== The principal soluble carbohydrates of mature soybeans are the disaccharide sucrose (range 2.5–8.2%), the trisaccharide raffinose (0.1–1.0%) composed of one sucrose molecule connected to one molecule of galactose, and the tetrasaccharide stachyose (1.4 to 4.1%) composed of one sucrose connected to two molecules of galactose. While the oligosaccharides raffinose and stachyose protect the viability of the soybean seed from desiccation (see above section on physical characteristics) they are not digestible sugars, so contribute to flatulence and abdominal discomfort in humans and other monogastric animals, comparable to the disaccharide trehalose. Undigested oligosaccharides are broken down in the intestine by native microbes, producing gases such as carbon dioxide, hydrogen, and methane. Since soluble soy carbohydrates are found in the whey and are broken down during fermentation, soy concentrate, soy protein isolates, tofu, soy sauce, and sprouted soybeans are without flatus activity. On the other hand, there may be some beneficial effects to ingesting oligosaccharides such as raffinose and stachyose, namely, encouraging indigenous bifidobacteria in the colon against putrefactive bacteria. The insoluble carbohydrates in soybeans consist of the complex polysaccharides cellulose, hemicellulose, and pectin. The majority of soybean carbohydrates can be classed as belonging to dietary fiber.
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boiling point Also vaporization point. The temperature at which a substance changes state from a liquid to a gas (or vapor). It depends on pressure and is usually specified for a given substance under standard conditions.
in the range of 108 – 1010 M−1 s−1. These enzymes are so efficient they effectively catalyse a reaction each time they encounter a substrate molecule and have thus reached an upper theoretical limit for efficiency (diffusion limit); and are sometimes referred to as kinetically perfect enzymes. But most enzymes are far from perfect: the average values of
== Chromatography == One of the main reasons to use response factors is to compensate for the irreproducibility of manual injections into a gas chromatograph (GC). Injection volumes for GCs can be 1 microliter (μL) or less and are difficult to reproduce. Differences in the volume of injected analyte leads to differences in the areas of the peaks in the chromatogram and any quantitative results are suspect. To compensate for this error, a known amount of an internal standard (a second compound that does not interfere with the analysis of the primary analyte) is added to all solutions (standards and unknowns). This way if the injection volumes (and hence the peak areas) differ slightly, the ratio of the areas of the analyte and the internal standard will remain constant from one run to the next. This comparison of runs also applies to solutions with different concentrations of the analyte. The area of the internal standard becomes the value to which all other areas are referenced. Below is the mathematical derivation and application of this method. Consider an analysis of octane (C8H18) using nonane (C9H20) as the internal standard. The 3 chromatograms below are for 3 different samples.
== Bioremediation properties == Pseudomonas fluorescens is increasingly recognized for its bioremediation potential, particularly in the degradation of environmental pollutants such as hydrocarbons. A study has shown that biostimulation and bioaugmentation with P. fluorescens can significantly contribute to the removal of total petroleum hydrocarbons (TPHs) from contaminated soil. This process is facilitated by the bacterium's production of biosurfactants, which increase the bioavailability of hydrocarbons for degradation. Further research has explored the biofilm-forming and denitrification capabilities of Pseudomonas species, including P. fluorescens, in eutrophic waters. The ability to form biofilms and produce extracellular polymeric substances (EPS) enhances the bioremediation potential of these bacteria. Specifically, strains that exhibit strong biofilm-forming and EPS production capabilities show higher nitrate removing capacity, which is crucial for combating water pollution. These findings underscore the importance of Pseudomonas fluorescens in environmental cleanup efforts and its potential application in treating oil-contaminated and nutrient-poor soils as well as nitrate-polluted water.
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.
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.