Khavinson is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-06-29. 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 proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
Interest in epitalon is usually discussed within the broader field of short peptide bioregulators, a category that includes other synthetic di-, tri-, and tetrapeptides studied by the same research group. These compounds share a common rationale: that small fragments of tissue-derived proteins can retain biological activity and can be produced reproducibly. The category as a whole remains outside mainstream pharmacological consensus, and epitalon specifically has a limited presence in independent, non-Russian research literature, which shapes how its evidence base is described.
| 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 |
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.
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 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.
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.
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 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.
== Use in biotechnology == Fat-free powdered milk is used as a saturating agent to block nonspecific binding sites on supports like blotting membranes (nitrocellulose, polyvinylidene fluoride (PVDF) or nylon), preventing binding of further detection reagents and subsequent background. It may be referred as Blotto. The major protein of milk, casein, is responsible for most of the binding site saturation effect.
It was first synthesized in 1540 by Valerius Cordus, who noted some of its medicinal properties. He called it oleum dulce vitrioli, a name that reflects the fact that it is synthesized by distilling a mixture of ethanol and sulfuric acid (known at that time as oil of vitriol). August Sigmund Frobenius gave the name Spiritus Vini Æthereus to the substance in 1730.
== Method == SISCAPA is an extension of the well-known gold-standard methods of stable-isotope dilution for quantitation of small molecules by mass spectrometry (MS). Rather than measure an intact protein directly by mass spectrometry, SISCAPA makes use of proteolytic digestion (e.g., with the enzyme trypsin) to cleave sample proteins into smaller peptides ideally suited to quantitation by mass spectrometry. By selecting a target peptide whose sequence occurs only in the selected target protein (a so-called “proteotypic” peptide), the target peptide can serve as a direct quantitative surrogate for the target protein (assuming the digestion process is complete, or at least reproducible). A synthetic version of the target peptide containing a stable isotope label is added in a known amount to the digested sample to serve as an internal standard (SIS). Since the target peptide and SIS are chemically indistinguishable throughout the workflow, but can be measured separately by a mass spectrometer due to the mass difference of the stable isotope label, their ratio provides the desired quantitative estimate of the target peptide amount. The SISCAPA workflow adds a specific enrichment step to the isotope dilution method in which a selected target peptide, together with its associated SIS internal standard, is captured by a sequence-specific anti-peptide antibody.
=== Post-Cold War === In late October 2019, a week before Commander of the Northern Fleet Aleksandr Moiseyev and Russian Foreign Minister Sergey Lavrov met their Norwegian counterparts in Kirkenes, Norway, ten submarines of Russia's Northern Fleet, among them two diesel-electric and eight non-strategic nuclear, left their homebases in the Kola Peninsula to participate in submarine drills that were the largest, on the Russian side, since Cold War operations Aport and Atrina. The main task of the submarines was reportedly testing Russian ability to breach the GIUK gap undetected and sail into the Atlantic Ocean. The drills were expected to last up to two months.
== Clinical significance == Patients with salt-sensitive hypertension have higher plasma ET-1. Endothelin-1 receptor antagonists (Bosentan) are used in the treatment of pulmonary hypertension. Use of these antagonists prevents pulmonary arterial constriction and thus inhibits pulmonary hypertension. As of 2020, the role of endothelin-1 in affecting lipid metabolism and insulin resistance in obesity mechanisms was under clinical research.
Sources: en.wikipedia.org
antiseptics, which are applied to living tissue/skin disinfectants, which destroy microorganisms found on non-living objects. antibiotics, called prophylactic when given as prevention rather as treatment of infection. However, long term use of antibiotics leads to resistance of bacteria. While humans do not become immune to antibiotics, bacteria do. Thus, avoiding using antibiotics longer than necessary helps prevent bacteria from forming mutations that aid antibiotic resistance. One of the ways to prevent or slow down the transmission of infectious diseases is to recognize the different characteristics of various diseases. Some critical disease characteristics that should be evaluated include virulence, distance traveled by those affected, and level of contagiousness. The human strains of Ebola virus, for example, incapacitate those infected extremely quickly and kill them soon after. As a result, those affected by this disease do not have the opportunity to travel very far from the initial infection zone. Also, this virus must spread through skin lesions or permeable membranes such as the eye. Thus, the initial stage of Ebola is not very contagious since its victims experience only internal hemorrhaging. As a result of the above features, the spread of Ebola is very rapid and usually stays within a relatively confined geographical area. In contrast, the human immunodeficiency virus (HIV) kills its victims very slowly by attacking their immune system.
If you are a libertarian you may find some nourishment in my book Letters to a Young Contrarian where I say that in the same breath as I-as I mourn the decay of some of my socialist allegiances that deep down I've always been a sympathizer of the libertarian anti-statist point of view. And one of the things that attracted me to socialism in the beginning was the idea of withering away of the state. In a 1986 video debate on Socialism vs Capitalism with John Judis VS Harry Binswanger and John Ridpath, Hitchens said:
=== Nitrogen reserve === Cyanophycin is a polymer consisting of a backbone of aspartic acid units with arginine side chains. It is synthesized by cyanobacteria and other bacteria either directly from arginine and aspartic acid or from the corresponding dipeptide, β-aspartylarginine, and serves as a nitrogen storage compound. In plants, particularly trees, arginine also plays a role in nitrogen storage. Under conditions of increased nitrogen availability, arginine—having the highest nitrogen content among amino acids—is preferentially synthesized and stored either as a free amino acid or within proteins. Trees also possess transport proteins for the uptake of arginine from the soil, and in conifers it represents a preferred nitrogen source. Various studies have shown that the xylem of trees contains high concentrations of free arginine compared to other amino acids, for example in citrus plants. Arginine is mobilized from arginine-containing storage proteins when needed. It also serves as a nitrogen source during germination, as demonstrated in studies on maritime pine.
Fatty acids are broken down to CO2 and water by the intra-cellular mitochondria through beta oxidation and the citric acid cycle. In the final step (oxidative phosphorylation), reactions with oxygen release a lot of energy, captured in the form of large quantities of ATP. Many cell types can use either glucose or fatty acids for this purpose, but fatty acids release more energy per gram. Fatty acids (provided either by ingestion or by drawing on triglycerides stored in fatty tissues) are distributed to cells to serve as a fuel for muscular contraction and general metabolism.
Sources: en.wikipedia.org
=== Portrayals in film === He and his insulin discovery have also been depicted in various media formats, including comic books, a biography by Michael Bliss, and on television. The National Film Board of Canada produced a short film in 1958, The Quest. The 1988 television movie Glory Enough for All depicted the search for insulin by Banting and Best, with R. H. Thomson starring as Banting. Banting is also portrayed by Jason Priestley boarding his fatal flight in the 2006 historical drama Above and Beyond.
==== Neurotransmitter receptors ==== DHEA has been found to directly act on several neurotransmitter receptors, including acting as a positive allosteric modulator of the NMDA receptor, as a negative allosteric modulator of the GABAA receptor, and as an agonist of the σ1 receptor.
A few bacteria have chemical systems that generate light. This bioluminescence often occurs in bacteria that live in association with fish, and the light probably serves to attract fish or other large animals. Bacteria often function as multicellular aggregates known as biofilms, exchanging a variety of molecular signals for intercell communication and engaging in coordinated multicellular behaviour. The communal benefits of multicellular cooperation include a cellular division of labour, accessing resources that cannot effectively be used by single cells, collectively defending against antagonists, and optimising population survival by differentiating into distinct cell types. For example, bacteria in biofilms can have more than five hundred times the increased resistance to antibacterial agents than individual "planktonic" bacteria of the same species. One type of intercellular communication by a molecular signal is called quorum sensing. Quorum sensing determines whether the local population is dense enough to support investment in processes that are only successful if large numbers of similar organisms behave similarly, such as excreting digestive enzymes or emitting light. Quorum sensing enables bacteria to coordinate gene expression and to produce, release, and detect autoinducers or pheromones that accumulate with the growth in cell population.
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.
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.