The short version of Epithalamin fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-10 and is reviewed periodically as new material appears.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
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.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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.
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.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
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.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
The first-generation Molteno and other nonvalved implants sometimes require the ligation of the tube until the bleb formed is mildly fibrosed and water-tight. This is done to reduce postoperative hypotony—sudden drops in postoperative intraocular pressure. Valved implants, such as the Ahmed glaucoma valve, attempt to control postoperative hypotony by using a mechanical valve. Ab interno implants, such as the Xen Gel Stent, are transscleral implants by an ab interno procedure to channel aqueous humor into the non-dissected Tenon's space, creating a subconjunctival drainage area similar to a bleb. The implants are transscleral and different from other ab interno implants that do not create a transscleral drainage, such as iStent, CyPass, or Hydrus. The ongoing scarring over the conjunctival dissipation segment of the shunt may become too thick for the aqueous humor to filter through. This may require preventive measures using antifibrotic medications, such as 5-fluorouracil or mitomycin-C (during the procedure), or other nonantifibrotic medication methods, such as collagen matrix implant, or biodegradable spacer, or later on create a necessity for revision surgery with the sole or combinative use of donor patch grafts or collagen matrix implant.
=== Other inorganic compounds === The pnictides of berkelium-249 of the type BkX are known for the elements nitrogen, phosphorus, arsenic and antimony. They crystallize in the rock-salt structure and are prepared by the reaction of either berkelium(III) hydride (BkH3) or metallic berkelium with these elements at elevated temperature (about 600 °C) under high vacuum. Berkelium(III) sulfide, Bk2S3, is prepared by either treating berkelium oxide with a mixture of hydrogen sulfide and carbon disulfide vapors at 1130 °C, or by directly reacting metallic berkelium with elemental sulfur. These procedures yield brownish-black crystals. Berkelium(III) and berkelium(IV) hydroxides are both stable in 1 molar solutions of sodium hydroxide. Berkelium(III) phosphate (BkPO4) has been prepared as a solid, which shows strong fluorescence under excitation with a green light. Berkelium hydrides are produced by reacting metal with hydrogen gas at temperatures about 250 °C. They are non-stoichiometric with the nominal formula BkH2+x (0 < x < 1). Several other salts of berkelium are known, including an oxysulfide (Bk2O2S), and hydrated nitrate (Bk(NO3)3·4H2O), chloride (BkCl3·6H2O), sulfate (Bk2(SO4)3·12H2O) and oxalate (Bk2(C2O4)3·4H2O). Thermal decomposition at about 600 °C in an argon atmosphere (to avoid oxidation to BkO2) of Bk2(SO4)3·12H2O yields the crystals of berkelium(III) oxysulfate (Bk2O2SO4). This compound is thermally stable to at least 1000 °C in inert atmosphere.
=== Human resources === In 2013, Merck KGaA reported problems with recruiting and retaining qualified employees: "Sourcing, recruiting and retaining specialists and talent at Merck are among the company's top priorities. Nevertheless, employee-related risks that affect business activities are likely, even though their impact is difficult to assess. Merck rates this as a medium risk." Merck KGaA further reported with respect to its pharma division, Merck Serono: "Over 80% of the Merck Serono senior management positions [have been] replaced since 2011 [as of September 2014]."
=== Generalised time reversible === Generalised time reversible (GTR) is the most general neutral, independent, finite-sites, time-reversible model possible. It was first described in a general form by Simon Tavaré in 1986. The GTR model is often called the general time reversible model in publications; it has also been called the REV model. The GTR parameters for nucleotides consist of an equilibrium base frequency vector,
Sources: en.wikipedia.org
biotechnology company specialized in the early discovery and development of recombinant polyclonal antibodies, after having acquired a significant stake in 2017. In 2022, Grifols acquired Biotest, a German manufacturer and provider of plasma-derived medicines.
== Effects == The down side of this method is that it is difficult to achieve as good results of glycemic control as with intensive insulin therapy. The advantage is that, for diabetics with a regular lifestyle, the regime is less intrusive than the intensive therapy.
== Characterization == Designing effective antimicrobial surfaces demands an in-depth understanding of the initial microbe-surface adhesion mechanisms. Scanning electron microscopy (SEM) is used for nonliving samples. Bacterial colony forming unit (CFU) counting requires overnight incubation and detects bacteria that readily grow on solid media. Molecular dynamics (MD) simulation can be used to minimize the number of experiments with engineered substrates, with the quantification of time-lapse fluorescence microscopy images that can be processed in an hour. Contact angle measurements can be used to characterize micro/nano-pillars use for rupturing cell walls. The analysis of the zeta potential by the streaming potential method of either an antimicrobial coating or a self-disinfectant material in contact with an aqueous environment, or by electrophoretic light scattering of nanoparticle dispersions of antibacterial additives reveal information about surface and interfacial charge and let predict the electrostatic attraction or repulsion of microorganisms.
Also, by changing economic incentives, precision agriculture may hinder environmental policies' effectiveness: "Precision agriculture can lead to higher marginal abatement costs in the form of forgone profits, decreasing producers' responsiveness to those policies." In other words, holding pollution constant, precision agriculture allows a farmer to produce more output, making abatement more expensive. Off-farm, digital agriculture has the potential to improve environmental monitoring and food system traceability. The monitoring costs of certifying compliance with environmental, health, or waste standards are falling because of digital technology. For example, satellite and drone imagery can track land use and/or forest cover; distributed ledger technologies can enable trusted transactions and exchange of data; food sensors can monitor temperatures to minimize contamination during storage and transport. Together, technologies like these can form digital agriculture traceability systems, which allow stakeholders to track agri-food products in near-real-time. Digital traceability yields a number of benefits, environmental and otherwise:
=== Laminin EGF-like === Beside different types of globular domains each laminin subunit contains, in its first half, consecutive repeats of about 60 amino acids in length that include eight conserved cysteines. The tertiary structure of this domain is remotely similar in its N-terminus to that of the EGF-like module. It is also known as a 'LE' or 'laminin-type EGF-like' domain. The number of copies of the laminin EGF-like domain in the different forms of laminins is highly variable; from 3 up to 22 copies have been found. In mouse laminin gamma-1 chain, the seventh LE domain has been shown to be the only one that binds with a high affinity to nidogen. The binding-sites are located on the surface within the loops C1-C3 and C5-C6. Long consecutive arrays of laminin EGF-like domains in laminins form rod-like elements of limited flexibility, which determine the spacing in the formation of laminin networks of basement membranes.
Sources: en.wikipedia.org
In this series a panel of seven academics, journalists and historians named her among the group of people in the UK "whose actions during the reign of Elizabeth II have had a significant impact on lives in these islands and given the age its character". In 2015 Hodgkin's 1949 paper The X-ray Crystallographic Investigation of the Structure of Penicillin was honoured by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society presented to the University of Oxford (England). This research is notable for its groundbreaking use of X-ray crystallography to determine the structure of complex natural products, in this instance, of penicillin. Since 1999, the Oxford International Women's Festival has presented the annual Dorothy Hodgkin Memorial Lecture, usually in March, in honour of Hodgkin's work. The Lecture is a collaboration between Oxford AWiSE (Association for Women in Science & Engineering), Somerville College and the Oxford University Museum of Natural History.
But it did get a little close there for a while. As you may know, there were 61 planes in the air headed toward Haïti at the time they finally agreed. And at one point General Biamby came in and told General Cédras that he had just gotten word on his telephone that the airplanes had taken off from Pope Air Force Base, with soldiers from Fort Bragg, and that both disconcerted them and caused them to be suspicious of the intent of the negotiations, but it also created a situation where immediately after that, the key points they had been refusing to agree to were agreed to, a date certain, other matters that I won't go into in detail here.
== Chestnut mimics == Bay horses also have reddish coats, but they have a black mane, tail, legs and other point coloration. The presence of true black points, even if obscured by white markings, means that a horse is not chestnut. Seal brown or dark bay horses are not chestnut but may be confused with a liver chestnut. Those unfamiliar with horse coat color terminology often call most horses "brown". including chestnuts. Brown, which may be difficult to distinguish visually from dark bay, is always accompanied by black points. Liver chestnuts, in particular, are mistakenly called brown or "seal brown". Silver bay horses typically have chocolate- to red-brown bodies with silvered mane, tail, and legs. The flat reddish-brown color and lack of easily identified black points can confuse even knowledgeable horse persons. Silver dapple horses usually hint at black or dark gray pigment at the roots of the mane and tail, and where their silver points end on the legs. Silvers look a bit "off"-chestnut. To further confuse matters, some flaxen chestnuts have silverish streaks in their manes and tails. However, genetic testing can clarify matters.
In the late 6th century, following Justinian I's wars, seven mobile field armies called comitatenses, numbering around 150,000 troops, were deployed around the empire; they remained the finest armies in Europe. They were aided by twenty-five frontier garrisons of approximately 195,000 lower-quality limitanei troops. Additional troops included subsidised allied forces and imperial guard units like the Scholae Palatinae. Naval forces were limited: flotillas were based at key locations, while 30,000 oarsmen were assembled to row 500, mostly requisitioned, transports to support the Vandalic War in Africa in 533. The losses suffered in the 7th-century Arab conquests led to fundamental changes. The field armies were withdrawn into the core Anatolian territories and assigned to settle in specific districts, which became known as themata and eventually replaced the old provinces. The thematic armies, supported by the proceeds of their districts, came to resemble a provincial militia with a small professional core, aided by foreign mercenaries and imperial regiments at Constantinople. To defend against its new Muslim enemy, the navy was similarly reorganised into several provincialised fleets. It became the dominant power in the eastern Mediterranean, with dromons equipped with Greek fire proving crucial on several occasions. As the 8th-century empire stabilised, the thematic militias proved rebellious and only suitable for defensive operations.
Sources: en.wikipedia.org
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.
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.
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.
It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.