epithalamin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-09-02. Anything still debated is marked as such rather than presented as settled.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
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 amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
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.
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.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
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.
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.
Yaws is typically found in humid tropical forest regions in South America, Africa, Asia, and Oceania. Yaws primarily affects children, with up to 80% of cases in those under 15 years of age, and peak incidence in children aged six to ten. Boys and girls are impacted equally. It is more common in remote areas, where access to treatment is poorer. It is associated with poverty and poor sanitation facilities and personal hygiene. Worldwide, almost 85% of yaws cases are in Ghana, Papua New Guinea, and the Solomon Islands. Rates in sub-Saharan Africa are low but tend to be concentrated in specific populations. As of 2015, it is estimated that about 89 million people live in yaws-endemic areas, but data are poor, and this is likely an overestimate. In the early 1900s, yaws was very common; in sub-Saharan Africa, it was more frequently treated than malaria, sometimes making up more than half of treatments. Mass treatment campaigns in the 1950s reduced the worldwide prevalence from 50 to 150 million to fewer than 2.5 million; however, during the 1970s, there were outbreaks in South-East Asia, and there have been continued sporadic cases in South America. As of 2011, it was unclear how many people worldwide were currently infected. From 2008 to 2012, 13 countries reported over 300,000 new cases to the WHO. There was no system for certifying local elimination of yaws, and it is not known whether the lack of reports from some countries is because they stopped having yaws cases or because they stopped reporting them.
After optimizing the concentration of graphene oxide concentration and anisotropic porous structure, tensile tests were performed. It was found that MGCA could recover 99.8% and 96.3% when compressed to 60% and 90% strain, respectively. SEM images showed that due to its unique structure, MCGA pore walls were able to wrinkle and fold during compression. Another unique characteristic of this material is its absorption capacity of 80-197 times its weight towards hydrophobic compounds, such as oils and chemical solvents. On the contrary, less effort has been made to study the stretchability of porous carbons. Gao, et al. synthesized a long-range lamellar scaffold composed of chitosan and graphene oxide via bidirectional freezing, freeze drying, and annealing. The result is a material with density of 11 mg cm−3 and porosity of about 99.4%. Various tensile tests were conducted, and it was found that carbon spring could revert to its original shape upon 80% compression strain and -60% stretching strain with a Poisson's ratio between 0.05 and 0.1. The narrow hysteresis loop of the stress-strain curve indicates a low energy dissipation (energy loss coefficient of about 0.2) because of its negligible interior friction, localized buckling, or cracks during deformation processes. The stretchable mechanical properties of this material allow for great candidates for vibrational and magnetism sensors.
=== Treatment by medical professionals === In a healthcare setting, treatment depends on the severity of symptoms and intravenous access. If a patient is conscious and able to swallow safely, food or drink may be administered, as well as glucose tabs or gel. In those with intravenous access, 25 grams of 50% dextrose is commonly administered. When there is no intravenous access, intramuscular or intra-nasal glucagon may be administered.
=== United Kingdom === In the UK, the firm Kemball, Bishop & Co. was asked in early 1941 if it could produce 45,000 litres (10,000 imp gal) of raw penicillin brew. Like Pfizer, with which it had a commercial relationship, it was a small firm, but one with experience in fermentation techniques as a manufacturer of citric acid. It was unable to do it at the time, but on 23 February 1942, Florey received an offer from Kemball, Bishop & Co. of a more modest effort of 910 litres (200 imp gal) every ten days. Work commenced at its Bromley-by-Bow plant on 5 March 1942 and the first trays of mould were seeded on 25 March.
The resulting force-displacement curves can be used to calculate elastic modulus. However, it is unclear whether particle size and indentation depth affect the measured elastic modulus of nanoparticles by AFM. Adhesion and friction forces are important considerations in nanofabrication, lubrication, device design, colloidal stabilization, and drug delivery. The capillary force is the main contributor to the adhesive force under ambient conditions. The adhesion and friction force can be obtained from the cantilever deflection if the AFM tip is regarded as a nanoparticle. However, this method is limited by tip material and geometric shape. The colloidal probe technique overcomes these issues by attaching a nanoparticle to the AFM tip, allowing control oversize, shape, and material. While the colloidal probe technique is an effective method for measuring adhesion force, it remains difficult to attach a single nanoparticle smaller than 1 micron onto the AFM force sensor. Another technique is in situ TEM, which provides real-time, high resolution imaging of nanostructure response to a stimulus. For example, an in situ force probe holder in TEM was used to compress twinned nanoparticles and characterize yield strength. In general, the measurement of the mechanical properties of nanoparticles is influenced by many factors including uniform dispersion of nanoparticles, precise application of load, minimum particle deformation, calibration, and calculation model. Like bulk materials, the properties of nanoparticles are materials dependent.
Sources: en.wikipedia.org
== Society and culture == Some cultures regard the liver as the seat of the soul. In Greek mythology, the gods punished Prometheus for revealing fire to humans by chaining him to a rock where a vulture (or an eagle) would peck out his liver, which would regenerate overnight (the liver is the only human internal organ that actually can regenerate itself to a significant extent). Many ancient peoples of the Near East and Mediterranean areas practiced a type of divination called haruspicy or hepatomancy, where they tried to obtain information by examining the livers of sheep and other animals. In Plato, and in later physiology, the liver was thought to be the seat of the darkest emotions (specifically wrath, jealousy and greed) which drive men to action. The Talmud (tractate Berakhot 61b) refers to the liver as the seat of anger, with the gallbladder counteracting this. The Persian, Urdu, and Hindi languages (جگر or जिगर or jigar) refer to the liver in figurative speech to indicate courage and strong feelings, or "their best"; e.g., "This Mecca has thrown to you the pieces of its liver!". The term jan e jigar, literally "the strength (power) of my liver", is a term of endearment in Urdu. In Persian slang, jigar is used as an adjective for any object which is desirable, especially women. In the Zulu language, the word for liver (isibindi) is the same as the word for courage. In English the term 'lily-livered' is used to indicate cowardice from the medieval belief that the liver was the seat of courage. Spanish hígados also means "courage".
nucleophile Any atom or molecule which can donate an electron pair to another atom or molecule. All molecules or ions with a free pair of electrons or at least one pi bond can act as nucleophiles, by which they are attracted to electron-deficient regions of other species; a chemical reaction involving a nucleophile donating an electron pair to an electrophile may be referred to as nucleophilic attack. Because they donate electrons, nucleophiles are Lewis bases by definition.
With its large size and geographic variety, the United States includes most climate types. East of the 100th meridian, the climate ranges from humid continental in the north to humid subtropical in the south. The western Great Plains are semi-arid. Many mountainous areas of the American West have an alpine climate. The climate is arid in the Southwest, Mediterranean in coastal California, and oceanic in coastal Oregon, Washington, and southern Alaska. Most of Alaska is subarctic or polar. Hawaii, the southern tip of Florida and U.S. territories in the Caribbean and Pacific are tropical. The United States receives more high-impact extreme weather incidents than any other country. States bordering the Gulf of Mexico are prone to hurricanes, and most of the world's tornadoes occur in the country, mainly in Tornado Alley. Due to climate change, extreme weather has become more frequent in the U.S. in the 21st century, with three times the number of reported heat waves compared to the 1960s. Since the 1990s, droughts in the American Southwest have become more persistent and more severe. The regions considered as the most attractive to the population are the most vulnerable.
Honorary Doctorate, California State University, Fullerton (CSUF) (May 2008) NASA Performance Award (2002 & 2001) NASA Go the Extra Mile (GEM) Award (2001) NASA Superior Accomplishment Award (2000) NASA Group Achievement Award – Russian Crusader Team (2000) Camille and Henry Dreyfus Postdoctoral Fellowship in Environmental Science (1997) Outstanding Doctoral Student Award in Chemistry from the University of California, Davis (1997) American Vacuum Society – HWhetten Award (1996) American Vacuum Society Graduate Research Award (1996) Pro Femina Research Consortium Graduate Research Award (1996) Pro Femina Research Consortium Graduate Award for Scientific Travel (1996) University of California, Davis Graduate Research Award (1996) University of California, Davis Graduate Student Award for Scientific Travel (1994) Patricia Roberts Harris Graduate Fellowship in Chemistry (1993–1997) Lyle Wallace Award for Service to the Department of Chemistry, California State University Fullerton (1993) National Science Foundation Research Experience for Undergraduates Award (1992) Council of Building & Construction Trades Scholarship (1991 and 1992) Big West Scholar Athlete (1989–1991)
Sources: en.wikipedia.org
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
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.