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Epitalon Background And Nomenclature — Reference Sheet

By Editorial Desk · published 2025-12-30 · last reviewed 2026-01-27 · News

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.

Updated 2026-01-27. Numbers and descriptions here follow the published literature rather than marketing material.

Epitalon Background and Nomenclature

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.

Research Claims and Evidence Status

Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.

No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.

The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.

Epitalon at a glance

PropertyValueNotes
Molecular formulaC14H22N4O9Computed for the free acid of Ala-Glu-Asp-Gly
Molecular massAbout 390.35 g/molFree peptide; salt forms shift the value
AppearanceWhite to off-white solidTypical of short peptides after freeze-drying
Solubility classFreely soluble in waterAqueous buffers are also commonly used
Common synonymsEpitalon, epithalone, AEDGAEDG is the single-letter sequence

Structure, Naming and Discovery

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.

Related pages on this site

Epitalon in Research Literature and Handling

Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.

Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.

Epitalon Structure and Research Origin

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.

Analytical Characterization and Stability

Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.

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.

Background from the literature

== Side effects == Side effects experienced with this product will resemble those of other benzodiazepines. Drowsiness and asthenia are common side effects. There has been a report of reversible hepatitis caused by clotiazepam.

Metribolone, also known as 17α-methyltrenbolone, as well as 17α-methyl-δ9,11-19-nortestosterone or 17α-methylestra-4,9,11-trien-17β-ol-3-one, is a synthetic estrane steroid and a 17α-alkylated derivative of nandrolone (19-nortestosterone). It is the C17α methylated derivative of trenbolone (δ9,11-19-nortestosterone) and the C9- and C11-dehydrogenated (δ9,11) analogue of normethandrone (17α-methyl-19-nortestosterone). Other close relatives and derivatives of metribolone include mibolerone (7α,17α-dimethyl-19-nortestosterone) and dimethyltrienolone (RU-2420; 7α,17α-dimethyl-δ9,11-19-nortestosterone). In addition to AAS, trimethyltrienolone (R2956; 2α,2β,17α-trimethyl-δ9,11-19-nortestosterone), a highly potent antiandrogen, has been derived from metribolone.

Suvorexant appeared to be similarly effective at 4 weeks to lemborexant (SMD 0.36, 95% CI 0.08 to 0.63) and daridorexant (SMD 0.23, 95% CI –0.01 to 0.48), whereas benzodiazepines and Z-drugs generally showed larger effect sizes (e.g., SMDs of 0.45 to 0.83) and antihistamines (e.g., doxepin, doxylamine, trimipramine) showed more similar efficacy (SMDs of 0.30 to 0.55). Orexin receptor antagonists like suvorexant increase total sleep time predominantly by increasing rapid eye movement sleep (REM) sleep, whereas they have no effect on or even decrease non-rapid eye movement (NREM) sleep. This is in contrast to most other hypnotics, which either do not affect REM sleep or decrease it. The implications of these differences are not fully clear. Unlike certain other hypnotics like benzodiazepines and Z-drugs, orexin receptor antagonists do not disrupt sleep architecture, and this might provide more restful sleep. It is unclear if suvorexant is safe among people with a history of substance addiction or alcoholism, as these individuals were excluded from clinical trials of suvorexant. A Cochrane review found suvorexant to be effective in the short-term treatment of sleep disturbances in people with dementia with few adverse effects. It is unknown if suvorexant is effective and safe for treatment of sleep problems in children and adolescents as suvorexant has not been studied in this context.

=== Cell layers === Transitional epithelium is made up of three types of cell layers: basal, intermediate, and superficial. The basal layer fosters the epithelial stem cells in order to provide constant renewal of the epithelium, and each basal cell contacts the basement membrane. These cells' cytoplasm is rich in tonofilaments and mitochondria; however, they contain few rough endoplasmic reticulum. The tonofilaments play a role in the attachment of the basal layer to the basement membrane via desmosomes. The intermediate cell layer is highly proliferative and, therefore, provides for rapid cell regeneration in response to injury or infection of the organ or tube in which it resides. These cells contain a prominent Golgi apparatus and an array of membrane-bound vesicles. These function in the packaging and transport of proteins, such as keratin, to the superficial cell layer. The cells of the superficial cell layer that lines the lumen are known as facet cells or umbrella cells. This layer is the only fully differentiated layer of the epithelium. It provides an impenetrable barrier between the lumen and the bloodstream, so as not to allow the bloodstream to reabsorb harmful wastes or pathogens. All transitional epithelial cells are covered in microvilli and a fibrillar mucous coat. The epithelium contains many intimate and delicate connections to neural and connective tissue. These connections allow for communication to tell the cells to expand or contract.

Sources: en.wikipedia.org

Reference notes

On August 10, 2022, Brian José Infante Machín, President of the Masonic Union for the Freedom of Cuba, published a Facebook post on the account of the Ibero-American-European Alliance against Communism, calling for a national strike on Fidel Castro's birthday, August 13. He told Freemasons that they should march in the streets in solidarity with those young people who had been mistreated by the government during the July 11th Protests. In September 2022, according to the 2022 edition of La Gran Logia (the magazine of the Grand Lodge of Cuba), the Supreme Court of Masonic Justice either expelled or ratified the expulsion of seven Freemasons from the fraternity in Cuba; Pavel Guillén Guzmán from Dos Ríos Lodge in Palma Soriano, Pedro Demesio Martínez González from Astrea Lodge in Centro Habana, Luis Alberto Reyes Expósito from Asilo de la Virtud Lodge in Cienfuegos, Brian José Infante Machín from Luz Caballero Lodge No. 81 in Marianao, Lester Damián Cañizares from Luz Caballero Lodge No. 81, and Manuel Arístides Suárez Álvarez from Victor Hugo Lodge in Matanzas.

Tang L, Wu JJ, Ma Q, et al. (July 2010). "Human lactoferrin stimulates skin keratinocyte function and wound re-epithelialization". The British Journal of Dermatology. 163 (1): 38–47. doi:10.1111/j.1365-2133.2010.09748.x. PMID 20222924. S2CID 2387064.

==== Inclusion of plasticizers ==== Inclusion of plasticizers tends to lower Tg and increase polymer flexibility. Addition of the plasticizer will also modify dependence of the glass-transition temperature Tg on the cooling rate. The mobility of the chain can further change if the molecules of plasticizer give rise to hydrogen bonding formation. Plasticizers are generally small molecules that are chemically similar to the polymer and create gaps between polymer chains for greater mobility and fewer interchain interactions. A good example of the action of plasticizers is related to polyvinylchlorides or PVCs. A uPVC, or unplasticized polyvinylchloride, is used for things such as pipes. A pipe has no plasticizers in it, because it needs to remain strong and heat-resistant. Plasticized PVC is used in clothing for a flexible quality. Plasticizers are also put in some types of cling film to make the polymer more flexible.

The major sports in Belize are football, basketball, volleyball and cycling, with smaller followings of boat racing, athletics, softball, cricket and rugby. Fishing is also popular in coastal areas of Belize. The Cross Country Cycling Classic, also known as the "cross country" race or the Holy Saturday Cross Country Cycling Classic, is considered one of the most important Belize sports events. This one-day sports event is meant for amateur cyclists but has also gained worldwide popularity. The history of Cross Country Cycling Classic in Belize dates back to the period when Monrad Metzgen picked up the idea from a small village on the Northern Highway (now Phillip Goldson Highway). The people from this village used to cover long distances on their bicycles to attend the weekly game of cricket. He improvised on this observation by creating a sporting event on the difficult terrain of the Western Highway, which was then poorly built. Another major annual sporting event in Belize is the La Ruta Maya Belize River Challenge, a 4-day canoe marathon held each year in March. The race runs from San Ignacio to Belize City, a distance of 290 kilometres (180 mi). On Easter day, citizens of Dangriga participate in a yearly fishing tournament. First, second, and third prize are awarded based on a scoring combination of size, species, and number. The tournament is broadcast over local radio stations, and prize money is awarded to the winners. The Belize national basketball team is the only national team that has achieved major victories internationally.

=== Outer membrane and surface antigens === The of T. pallidum has several features that have made it historically difficult to research. These include details such as its fragility. The treponemal outer membrane (OM) proteins are key factors for the bacterium's pathogenesis, persistence, and immune evasion strategies. Treponema's reputation as a "stealth pathogen" is primarily due to this unique (OM) structure, which serves to evade immune detection. The outer membrane of Treponema pallidum contains a strikingly low concentration of transmembrane proteins, approximately 100-fold lower than other gram-negative bacteria or other spirochetes. This protects the cells from antibodies attacking it, hence they exhibit a "puzzling lack of antigenicity". The genome also revealed a bundle of 12 proteins and some putative hemolysins are potential virulence factors of T. pallidum. One protein, TprK, appears to constantly mutate to avoid immune response from its host.

Sources: en.wikipedia.org

Notes from published material

=== Career === After receiving his doctorate, Gish worked as an assistant research associate at Berkeley, and as an assistant professor at Cornell University Medical College for eighteen years, joining the Upjohn Company as a research associate in 1960.

Adherent leucoma: results when healing occurs after perforation of cornea with incarceration of iris. The iris is adherent to the back of a leucomatous cornea. One of the major complication of adherent leucoma is Secondary glaucoma Corneoiridic scar: if iris tissue is incarcerated and incorporated within the scar tissue, as occurs in healing of a large sloughed corneal ulcer, it is called a corneoiridic scar. Corneal facet: corneal surface depressed at the site of healing (due to less fibrous tissue); such a scar is called facet. Kerectasia: In this condition, corneal curvature is increased at the site of opacity (bulge due to weak scar).

Antipsychotics are generally a first-line treatment for delirium; however, when delirium is caused by alcohol or sedative hypnotic withdrawal, benzodiazepines are a first-line treatment. There is some evidence that low doses of benzodiazepines reduce adverse effects of electroconvulsive therapy.

== Medical uses == Imetelstat is indicated for the treatment of adults with low- to intermediate-1 risk myelodysplastic syndromes with transfusion-dependent anemia requiring four or more red blood cell units over eight weeks who have not responded to or have lost response to or are ineligible for erythropoiesis-stimulating agents.

Sources: en.wikipedia.org

Frequently asked questions

What is epitalon made of?

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.

Why do two spellings appear in the literature?

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.

Is epitalon the same substance as epithalamin?

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.

Has epitalon been studied in people?

Small studies with human participants have been reported, chiefly in Russian-language journals, but they are limited in size and design. No large randomised controlled trial with published results is available.

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