A practical reference on bioregulator: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-08-10. Anything still debated is marked as such rather than presented as settled.
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.
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.
Identity and purity of epitalon samples are normally established by reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, combined with mass spectrometry. The mass spectrum confirms the expected molecular ion and can reveal truncated or oxidised by-products. Amino acid analysis after acid hydrolysis verifies that the four residues are present in the expected ratio. Certificates typically report a purity figure taken from chromatographic peak area, expressed as a percentage of total integrated signal.
Lyophilised epitalon is generally held at minus twenty degrees Celsius in a sealed container kept dry and dark. Cooler conditions are sometimes recommended for long-term archives. The solid takes up moisture readily enough that repeated opening of a vial introduces water, so dividing a batch into smaller portions before storage lowers degradation risk. Aqueous solutions are less durable than the dry powder and are usually prepared shortly before use, then kept cold and shielded from light to slow hydrolysis and oxidation.
Verification of research-grade material involves comparing a supplier chromatogram against an in-house reference, checking the observed mass against the calculated value, and where possible confirming residue order by tandem mass spectrometry or enzymatic peptide mapping. Purity claims should be read alongside the method used to obtain them, because detection wavelength and integration settings alter the result. Batch-specific data, rather than a generic grade statement, is the informative part of a certificate.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
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.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
The most frequently cited proposed action is induction of telomerase, the enzyme that adds repeat sequences to chromosome ends. Cell-culture work from the originating group reported higher telomerase reverse transcriptase expression and measurable telomere elongation in human somatic cells after exposure. How a four-residue peptide would reach nuclear gene regulation is not established, and no cell-surface receptor or uptake route has been identified. Additional reports describe changes in melatonin secretion, antioxidant enzyme activity and lipid peroxidation in aged animals, but these findings remain mechanistically unconnected to the telomerase observation.
Published evidence comes mainly from Russian-language journals and from a single research group, with small sample sizes and limited independent replication. A few laboratories outside that group have examined related peptides and reported weaker or absent telomerase effects, so the central claim is best described as contested rather than settled. Rodent studies report modest changes in some ageing markers and in survival, but designs vary and control conditions are often sparse. No large randomised trial in humans has been published, and long-term safety data in healthy populations are correspondingly thin.
==== Limitations ==== Because relatively few cells are counted in the manual differential, the variability is higher than in automated techniques, especially when cells are present in low amounts. For example, in a sample containing 5 percent monocytes, the manual differential results could be between 1 and 10 percent due to sampling variation. Additionally, cell identification is subjective and the accuracy depends on the skills of the person reading the slide. Poor blood smear preparation can cause an uneven distribution of white blood cells, resulting in inaccurate counting, and improper staining can impede cell identification. Overall, manual differential counts exhibit coefficients of variation (CVs) ranging from 5 to 10 percent, while automated differential counts of normal neutrophils and lymphocytes have CVs of about 3 percent. In leukemias and other hematologic malignancies, the lineage and genetic characteristics of white blood cells have important implications for treatment and prognosis, and the microscopic appearance of the cells is often insufficient for accurate classification. In these cases, other techniques such as immunophenotyping by flow cytometry or special staining can be used to definitively identify the cells.
"Biochemical Society". The Virtual Library of Biochemistry, Molecular Biology and Cell Biology Biochemistry, 5th ed. Full text of Berg, Tymoczko, and Stryer, courtesy of NCBI. SystemsX.ch – The Swiss Initiative in Systems Biology Archived 2017-01-19 at the Wayback Machine Full text of Biochemistry by Kevin and Indira, an introductory biochemistry textbook.
N-Demethylation to noroxycodone predominantly via CYP3A4 O-Demethylation to oxymorphone predominantly via CYP2D6 6-Ketoreduction to 6α- and 6β-oxycodol N-Oxidation to oxycodone-N-oxide In humans, N-demethylation of oxycodone to noroxycodone by CYP3A4 is the major metabolic pathway, accounting for 45% ± 21% of a dose of oxycodone, while O-demethylation of oxycodone into oxymorphone by CYP2D6 and 6-ketoreduction of oxycodone into 6-oxycodols represent relatively minor metabolic pathways, accounting for 11% ± 6% and 8% ± 6% of a dose of oxycodone, respectively. Several of the immediate metabolites of oxycodone are subsequently conjugated with glucuronic acid and excreted in the urine. 6α-Oxycodol and 6β-oxycodol are further metabolized by N-demethylation to nor-6α-oxycodol and nor-6β-oxycodol, respectively, and by N-oxidation to 6α-oxycodol-N-oxide and 6β-oxycodol-N-oxide (which can subsequently be glucuronidated as well). Oxymorphone is also further metabolized, as follows:
Sources: en.wikipedia.org
=== Alternative treatments === Elements bordering the metal–nonmetal dividing line are not always classified as metalloids, noting a binary classification can facilitate the establishment of rules for determining bond types between metals and nonmetals. In such cases, the authors concerned focus on one or more attributes of interest to make their classification decisions, rather than being concerned about the marginal nature of the elements in question. Their considerations may or not be made explicit and may, at times, seem arbitrary. Metalloids may be grouped with metals; or regarded as nonmetals; or treated as a sub-category of nonmetals. Other authors have suggested classifying some elements as metalloids "emphasizes that properties change gradually rather than abruptly as one moves across or down the periodic table". Some periodic tables distinguish elements that are metalloids and display no formal dividing line between metals and nonmetals. Metalloids are instead shown as occurring in a diagonal band or diffuse region. The key consideration is to explain the context for the taxonomy in use.
=== Control strategies === There is no known method of eradication or control for invasive Cercopagis pengoi. Containing the spread to new areas is the only form of management. Stricter ballast water regulations and awareness would prevent the spread. The C. pengoi invasion of the Great Lakes occurred after the United States passed a regulation requiring ships exchange freshwater ballast water with ocean water to kill off potential invaders. This means that either the resting eggs remain viable even after boats filled with ballast water switch out their ballast water in the ocean, or the required ballast water regulations are not being followed, or the species was brought into the Great Lakes in no-ballast-on-board (NOBOB) vessels (the most like possibility). NOBOB vessels carry only residual water (<50000L) but were not required to exchange ballast water at the time of Cercopagis' invasion. Locally C. pengoi spread can be limited by only releasing bait or bait water into the water body where the bait was originally collected. Boat owners should wash their boats and equipment with high pressure and hot water (above 40 °C) to limit the spread of adult C. pengoi. Alternatively boats and equipment should be allowed to dry for at least five days before moving to another body of water.
== Regulation == The cellular protein levels of IRS-1 are regulated by the Cullin-7 E3 ubiquitin ligase, which targets IRS-1 for ubiquitin mediated degradation by the proteasome. Different Serine phosphorylation of IRS-1, caused by various molecules, such as fatty acids, TNFα and AMPK, has different effects on the protein, but most of these effects include cellular re-localization, conformational and steric changes. These processes lead to decrease in Tyrosine phosphorylation by insulin receptors and diminished PI3K recruitment. Altogether, these mechanisms stimulate IRS-1 degradation and insulin resistance. Other inhibitory pathways include SOCS proteins and O-GlcNAcylation of IRS-1. SOCS proteins act by binding to IR and by interfering with IR phosphorylation of IRS-1, therefore attenuating insulin signaling. They can also bind to JAK, causing a subsequent decrease in IRS-1 tyrosine phosphorylation. During insulin resistance induced by hyperglycemia, glucose accumulates in tissues as its hexosamine metabolite UDP-GlcNAc. This metabolite if present in high amounts leads to O-GlcNAc protein modifications. IRS-1 can undergo this modification, which results in its phosphorylation and functional suppression.
Sources: en.wikipedia.org
Jaundice (yellow skin and/or whites of the eyes) This is where bilirubin deposits in skin, causing an intense itch. Itching is the most common complaint by people who have liver failure. Often this itch cannot be relieved by drugs. Fluid accumulating in the abdomen, and swelling of the ankles and feet occurs because the liver fails to make albumin. Excessive fatigue occurs from a generalized loss of nutrients, minerals and vitamins. Bruising and easy bleeding are other features of liver disease. The liver makes clotting factors, substances which help prevent bleeding. When liver damage occurs, these factors are no longer present and severe bleeding can occur. Pain in the upper right quadrant can result from the stretching of Glisson's capsule in conditions of hepatitis and pre-eclampsia.
physical chemistry The branch of chemistry that studies chemical systems in terms of the principles, practices, and concepts of physics, such as motion, energy, force, time, thermodynamics, chemical equilibrium, and statistical mechanics, among others. In contrast to chemical physics, physical chemistry is predominantly (though not entirely) a macroscopic science that studies the physical and chemical interactions of bulk quantities of matter.
=== Relation of PIDD1 to centrosomes === Recent investigations reveal that CASP2 activation, which is dependent on PIDD1, does not lead to cell death or activate p53 in reaction to DNA damage (such as that induced by doxorubicin) or during prolonged mitotic arrest (as observed with taxol treatment). In contrast, the p53 activation linked to centrosome amplification—a process that can occur following failed cytokinesis—undoubtedly depends on the Caspase-2−PIDDosome complex. Notably, PIDD1 appears to be integral in assessing the quantity of mature mother centrioles, utilizing a mechanism that has yet to be fully clarified. Furthermore, PIDD1 is situated at the distal ends of mature centrosomes within normal cells, suggesting its potential role in regulating centrosomal functions. The assembly of the Caspase-2−PIDDosome can be triggered by the presence of multiple mature centrioles with appendages. This activation leads to CASP2-mediated cleavage of MDM2, resulting in the accumulation of p53 and subsequent cell cycle arrest mediated by p21. Notably, these processes occur without causing significant cell death. Similarly, the depletion of centrosomes undermines the effectiveness of this pathway during instances of cytokinesis failure. In contrast, overexpressing polo-like kinase 4 (PLK4), which promotes the formation of additional centrosomes, is sufficient to activate the pathway even when cytokinesis is not compromised.
Sources: en.wikipedia.org
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.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
The usual approach is reversed-phase HPLC with ultraviolet detection, reported as a percentage of total peak area. Mass spectrometry is used alongside chromatography to confirm identity rather than purity alone.