The short version of bioregulator fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-09-21. Anything still debated is marked as such rather than presented as settled.
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.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. It was designed at the St. Petersburg Institute of Bioregulation and Gerontology as a short, chemically defined analogue of epithalamin, a fraction obtained from bovine pineal tissue. Small peptide bioregulators of this type formed a long-running line of work there from the 1980s onward. Because the molecule is produced by solid-phase synthesis rather than extraction, its composition is exact and its purity can be measured directly.
Solubility is high in water, phosphate-buffered saline and normal saline, a pattern that follows from the two acidic residues in the chain. The peptide dissolves poorly in non-polar solvents such as hexane or chloroform. Stock solutions are often prepared in water first and then diluted into the buffer of interest. Because the molecule is small and hydrophilic, filtration through a low-protein-binding membrane is usually straightforward, and visible particulates are uncommon in freshly made solutions.
Identity and purity are established with reversed-phase high-performance liquid chromatography and mass spectrometry. The chromatogram shows the main peak and any truncated or oxidised by-products, while the mass spectrum confirms the expected 390 dalton mass. Amino acid analysis can corroborate composition when a sample's origin is uncertain. Counterion content, particularly residual trifluoroacetate from purification, is frequently reported alongside purity because it shifts the net mass of the solid.
Reference material is normally supplied as a lyophilised powder in a sealed vial. Product literature typically recommends storage at minus twenty degrees Celsius or colder, protected from light and moisture. Freeze-thaw cycling is usually avoided because repeated condensation can introduce water into the vial. Working solutions are commonly prepared fresh, aliquoted, and kept cold for short periods rather than stored at ambient temperature. Labelling the date of opening helps track how long a vial has been in use.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Calculated from the four residues with three water losses |
| Molecular mass | About 390.35 g/mol | Monoisotopic mass near 390.14, used for mass-spectrometric identification |
| Peptide sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG; no disulfide bonds or modified residues |
| Appearance | White to off-white solid | Supplied as a dried powder |
| Isoelectric point | Around 4 | Estimated from aspartate and glutamate side-chain pKa values |
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.
Peptides of this size are generally stable as dry solids but degrade in solution over time. The principal routes are hydrolysis of the peptide backbone and oxidation, with hydrolysis favoured by elevated temperature and extreme pH. Aqueous solutions held at room temperature can show measurable loss of purity within days, while frozen aliquots are considerably more durable. Because the sequence contains neither cysteine nor methionine, oxidation is less of a concern than for many other peptides, but pH control during handling still matters.
Typical storage for the lyophilized powder is −20 °C or lower, in a sealed container protected from light and moisture. Hygroscopic material should be allowed to equilibrate to room temperature before the vial is opened, which limits condensation on the contents. Working solutions are commonly divided into single-use aliquots and frozen to avoid repeated freeze-thaw cycles. Dilute solutions are more prone to adsorption onto plastic surfaces and to loss during filtration, so procedures that minimize transfers and use low-binding labware are preferable.
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.
According to the Soviet astronomer, the Earth's civilization would be too young to be able to contact another civilization that would certainly be more advanced; the Solar System is too young with its 5 billion years, and the first ancestors of today's man appeared only 6 million years ago at the earliest; the oldest celestial objects are between 10 and 14 billion years old; it is clear that the other civilizations are incomparably older than the human civilization. Therefore, the knowledge of these civilizations must be greater than Earth's, and, he reasoned, they must surely be aware of what humans are doing. Kardashev believed it is probable that the present state of Earth's civilization is only one of the stages through which civilizations pass during their evolution. It is thus possible to define civilization on the basis of this universal characteristic, which allowed Aleksandr Lyapunov to define life as "a highly stable state of matter, which uses information encoded by the states of individual molecules to produce maintaining reactions", which Kardashev calls the "functional definition of civilization".
Baikiain is an organic compound with the molecular formula C6H9NO2. Chemically, it is classified as a tetrahydropyridine substituted with a carboxylic acid. Because it contains both this carboxylic acid and an adjacent amine group, it is also an alpha-amino acid. Baikiain is one of the two enantiomers of the chiral compound 4,5-didehydropipecolic acid.
Flavoring are often added to e-liquids as well as dry smoke blends. There are currently over 7,700 e-liquid flavors available, most have not been laboratory tested for toxicity. There are numerous flavors (e.g., fruit, vanilla, caramel, coffee) of e-liquid available. There are also flavorings that resemble the taste of cigarettes.
=== Notable individuals === Alfredo Ferrari was an Italian automotive engineer, the eldest son of automaker Enzo Ferrari, and the planned heir to his father's sports car company, Ferrari. Alfredo died of DMD on 30 June 1956 at the age of 24. Rapper and disability rights advocate Darius Weems had the disease and used his notoriety to raise awareness and funds for treatment, as seen in the documentary Darius Goes West (2007). He died at the age of 27 in 2016. In 2024, Netflix released a documentary film about a young man with the disease, The Remarkable Life of Ibelin. The film explores the life of Mats Steen and the impact he had on his World of Warcraft guild Starlight, where Mats spent much of his time.
Sources: en.wikipedia.org
== Function == Citrulline is a metabolic intermediate within the urea cycle, which is the pathway by which mammals excrete ammonia by converting it into urea. Citrulline is also produced as a byproduct of the enzymatic production of nitric oxide from the amino acid arginine, catalyzed by nitric oxide synthase. In the yeast species Saccharomyces cerevisiae, citrulline is a metabolic intermediate in the latter, cytosolic half of the arginine biosynthesis pathway. Several proteins contain citrulline as a result of a post-translational modification. These citrulline residues are generated by a family of enzymes called peptidylarginine deiminases, which convert arginine into citrulline in a process called citrullination or deimination with the help of calcium ions. Proteins that normally contain citrulline residues include myelin basic protein, filaggrin, and several histone proteins, whereas other proteins, such as fibrin and vimentin are susceptible to citrullination during cell death and tissue inflammation. Circulating citrulline concentration is a biomarker of intestinal functionality.
Klüver wrote that "many 'atypical' visions are upon close inspection nothing but variations of these form-constants." An unusual but unique characteristic of mescaline use is the "geometrization" of three-dimensional objects. The object can appear flattened and distorted, similar to the presentation of a Cubist painting. Detailed descriptions of the psychedelic experience induced by mescaline have been given by many authors. The subjective effects of mescaline are qualitatively similar to those of LSD and psilocybin. Based on anecdotal evidence however, mescaline is said to be less threatening and to produce less ego dissolution than other psychedelics like LSD. This may in part be due its slow onset allowing for a more comfortable ease-in of effects. In addition, mescaline is typically dosed at lower doses than LSD or psilocybin in terms of doses with equivalent or comparable strength. According to a study in the Netherlands, ceremonial San Pedro use seems to be characterized by relatively strong spiritual experiences, and low incidence of challenging experiences. Mescaline, LSD, and psilocybin appear to produce similar color enhancement in clinical studies, though more research is needed.
==== Megastigmatrienone ==== Tobacco aroma is due to the presence of different volatile compounds; megastigmatrienone is the key flavor compound in tobacco. Megastigmatrienone is used as flavor in tobacco products as well. Megastigmatrienone, a cyclohexenone, and a carotenoid-derived aromatic compound, produces spice notes associated with wine. Megastigmatrienone is a metabolite of Brewer's yeast. Megastigmatrienone, as Tabanone, is manufactured by Symrise as a perfume ingredient.
It is also used off-label in the management of moderate to severe cases of serotonin syndrome, a complex of symptoms associated with the use of serotonergic drugs, such as selective serotonin reuptake inhibitors (and monoamine oxidase inhibitors), and in cases of high levels of serotonin in the blood resulting from a serotonin-producing carcinoid tumor. There is uncertainty about the proper dose of cyproheptadine for treatment of serotonin syndrome, with doses of 4 to 16 mg having been employed but doses of 20 to 30 mg possibly actually being necessary based on positron emission tomography (PET) imaging research. Cyproheptadine has sedative effects and can be used to treat insomnia similarly to other centrally-acting antihistamines. The recommended dose for this use is 4 to 8 mg.
== Career == Eke's clinical and research career focuses on the intersection of maternal fetal medicine and pharmacologic research. He serves as the protocol chair for the International Maternal Pediatric Adolescent AIDS Clinical Trials Group (IMPAACT) 2041, a phase I/II clinical trial evaluating the pharmacokinetics and safety of glecaprevir/pibrentasvir initiated during pregnancy among women with hepatitis C, including women co-infected with HIV. He is also involved in longitudinal cohort studies examining cardiovascular and metabolic outcomes in pregnant and postpartum women. His global health work includes contributions to Supporting, Mobilizing, and Accelerating Research for Tuberculosis Elimination (SMART4TB), a tuberculosis research initiative that integrates detection, prevention, and treatment strategies to reduce the burden of TB in high-risk settings. His broader research interests include optimizing drug safety and dosing in pregnancy and lactation, particularly in contexts such as preterm birth, HIV, tuberculosis, sickle cell disease, hypertensive disorders of pregnancy, and opioid use in pregnancy.
Sources: en.wikipedia.org
=== Other uses in arts, entertainment and media === C4 (New Zealand TV channel), a former New Zealand television music channel 1. c4, also called the English Opening, a chess opening Channel 4, British TV channel abbreviated "C4"
== Data produced by structural alignment == The minimum information produced from a successful structural alignment is a set of residues that are considered equivalent between the structures. This set of equivalences is then typically used to superpose the three-dimensional coordinates for each input structure. (Note that one input element may be fixed as a reference and therefore its superposed coordinates do not change.) The fitted structures can be used to calculate mutual RMSD values, as well as other more sophisticated measures of structural similarity such as the global distance test (GDT, the metric used in CASP). The structural alignment also implies a corresponding one-dimensional sequence alignment from which a sequence identity, or the percentage of residues that are identical between the input structures, can be calculated as a measure of how closely the two sequences are related.
=== Cardiovascular === Agmatine produces mild reductions in heart rate and blood pressure, apparently by activating both central and peripheral control systems via modulation of several of its molecular targets including: imidazoline receptors subtypes, norepinephrine release and NO production.
BFP derivatives (except mKalama1) contain the Y66H substitution. They exhibit a broad absorption band in the ultraviolet centered close to 380 nanometers and an emission maximum at 448 nanometers. A green fluorescent protein mutant (BFPms1) that preferentially binds Zn(II) and Cu(II) has been developed. BFPms1 have several important mutations including and the BFP chromophore (Y66H),Y145F for higher quantum yield, H148G for creating a hole into the beta-barrel and several other mutations that increase solubility. Zn(II) binding increases fluorescence intensity, while Cu(II) binding quenches fluorescence and shifts the absorbance maximum from 379 to 444 nm. Therefore, they can be used as a Zn biosensor.
Sources: en.wikipedia.org
No. Epithalamin is a peptide-containing extract of bovine pineal glands, while epitalon is a single synthetic tetrapeptide. The extract contains many peptides and other tissue components, so its composition varies between batches in ways that a synthesised sequence does not.
It is not recognised as an endogenous peptide hormone. The four-residue sequence can appear inside larger proteins and in digestive fragments of dietary protein, but no dedicated pathway producing it as a signalling molecule has been identified.
Several cell-culture reports describe increased telomerase activity after treatment, measured by enzyme assays or by transcript levels. Results differ between cell types and laboratories, and measured telomere lengthening has been reported in some studies but not in others, which leaves the physiological relevance open.
Sealed lyophilised powder is normally kept at minus twenty degrees Celsius or below, away from light and moisture. Vials are allowed to reach room temperature before opening to limit condensation. Repeated warming and cooling of the same vial is discouraged.