A practical reference on epithalamin: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-11-06 and is reviewed periodically as new material appears.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
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.
Storage practice centres on limiting moisture, oxygen, and repeated temperature cycling. Freeze-dried powder is generally held desiccated at minus twenty degrees Celsius or colder and protected from light. Reconstituted solutions are markedly less stable, and the aspartate-glycine junction is prone to succinimide formation at neutral to mildly alkaline pH. Portioning material into single-use aliquots reduces degradation compared with repeated freeze-thaw cycles. Stability data specific to this tetrapeptide remain scarce, so most handling guidance is extrapolated from general peptide chemistry rather than measured directly.
Documentation accompanying research peptides usually includes a certificate of analysis listing the batch number, purity figure, and test methods applied. Buyers comparing suppliers should check whether the reported purity refers to chromatographic area or to a mass-balance calculation, because the two are not equivalent. Counter-ion content, residual solvents, and water content are sometimes omitted from such certificates even though they affect the actual peptide mass present. Independent verification through a second laboratory is the most direct way to confirm that a supplied material matches its label.
Purity assessment of peptide reagents normally relies on reversed-phase high-performance liquid chromatography. A gradient of acetonitrile in water with trifluoroacetic acid, paired with a C18 stationary phase, separates the target tetrapeptide from truncated sequences and deletion analogues. Detection at 214 nanometres exploits absorbance of the peptide backbone, since the molecule contains no aromatic residue. Results are expressed as a percentage of total peak area. Values above ninety-five percent are typical for research-grade material, although reporting conventions vary between suppliers.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four amino acid residues |
| Residue sequence | Ala-Glu-Asp-Gly | Abbreviated AEDG |
| Approximate mass | 390.35 Da | Monoisotopic, free base form |
| Parent preparation | Epithalamin extract | Derived from pineal tissue |
| Common spelling variants | Epithalon, epithalone, AEDG | Affects literature retrieval |
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.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
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.
Reversed-phase high-performance liquid chromatography is the standard approach for assessing purity, usually with ultraviolet detection near 214 nm, where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the molecular mass and helps reveal truncation or deletion byproducts. Amino acid analysis can verify composition, and counterion content is sometimes measured because peptides purified with trifluoroacetic acid retain variable amounts of that salt. Purity figures reported without a stated method and detection wavelength are difficult to interpret.
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 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.
In 1992, Eric Taub brought ibogaine to an offshore location close to the United States, where he began providing treatments and popularizing its use. In Costa Rica, Lex Kogan, another leading proponent, joined Taub in systematizing its administration. The two men established medically monitored treatment clinics in several countries. In 1981, an unnamed European manufacturer produced 44 kg of iboga extract. The entire stock was purchased by Carl Waltenburg, who distributed it under the name "Indra extract" and used it in 1982 to treat heroin addicts in the community of Christiania, Copenhagen. Indra extract was available for sale over the Internet until 2006, when the Indra web presence disappeared. Various products are currently sold in several countries as "Indra extract", but it is unclear if any of them are derived from Waltenburg's original stock. Ibogaine and related indole compounds are susceptible to oxidation over time. The National Institute on Drug Abuse (NIDA) began funding clinical studies of ibogaine in the United States in the early 1990s, including conducting a clinical study in 1993, but terminated the project in 1995 following the unexpected death of a female participant. Data demonstrating ibogaine's efficacy in attenuating opioid withdrawal in drug-dependent human subjects was published by Alper et al. in 1999. A cohort of 33 patients were treated with 6 to 29 mg/kg of ibogaine; 25 displayed resolution of the signs of opioid withdrawal from 24 hours to 72 hours post-treatment, but one 24-year-old female, who received the highest dosage, died.
==== Student loan repayments ==== Student loan repayments made by employers to their employees were temporarily tax-free to the employees but they are now permanently tax-free. The tax-free limit per year will be indexed for inflation starting in 2026.
=== Misinformation === TikTok has banned Holocaust denial, but other conspiracy theories have become popular on the platform, such as Pizzagate and QAnon (two conspiracy theories popular among the US alt-right) whose hashtags reached almost 80 million views and 50 million views respectively by June 2020. The platform has also been used to spread misinformation about the COVID-19 pandemic, such as clips from Plandemic. TikTok removed some of these videos and has generally added links to accurate COVID-19 information on videos with tags related to the pandemic. In January 2020, left-leaning media watchdog Media Matters for America said that TikTok hosted misinformation related to the COVID-19 pandemic despite a recent policy against misinformation. In April 2020, the government of India asked TikTok to remove users posting misinformation related to the COVID-19 pandemic. There were also multiple conspiracy theories that the government is involved with the spread of the pandemic. It reported that in the second half of 2020, over 340,000 videos in the US about election misinformation and 50,000 videos of COVID-19 misinformation were removed. To combat misinformation in the 2022 midterm election in the US, TikTok announced a midterms Elections Center available in-app to users in 40 different languages. TikTok partnered with the National Association of Secretaries of State to give accurate local information to users.
=== Category:EC 1.7 (act on other nitrogenous compounds as donors) === Category:EC 1.7.1 (with NAD+ or NADP+ as acceptor) Category:EC 1.7.2 (with a cytochrome as acceptor) Category:EC 1.7.3 (with oxygen as acceptor) Urate oxidase EC 1.7.3.3 Category:EC 1.7.7 (with an iron–sulfur protein as acceptor) Category:EC 1.7.99 (with other acceptors) Nitrite reductase EC 1.7.99.3 Nitrate reductase EC 1.7.99.4
Sources: en.wikipedia.org
Some forms of MODY produce significant hyperglycemia and the typical signs and symptoms of diabetes: increased thirst and urination (polydipsia and polyuria). In contrast, many people with MODY have no signs or symptoms and are diagnosed either by accident, when a high glucose is discovered during testing for other reasons, or screening of relatives of a person discovered to have diabetes. Discovery of mild hyperglycemia during a routine glucose tolerance test for pregnancy is particularly characteristic. While the goals of diabetes management are the same no matter what type, there are two primary advantages of confirming a diagnosis of MODY.
Polyphenol oxidase (PPO; also polyphenol oxidase i, chloroplastic), an enzyme involved in fruit browning, is a tetramer that contains four atoms of copper per molecule. PPO may accept monophenols and/or o-diphenols as substrates. The enzyme works by catalyzing the o-hydroxylation of monophenol molecules in which the benzene ring contains a single hydroxyl substituent to o-diphenols (phenol molecules containing two hydroxyl substituents at the 1, 2 positions, with no carbon between). It can also further catalyse the oxidation of o-diphenols to produce o-quinones. PPO catalyses the rapid polymerization of o-quinones to produce black, brown or red pigments (polyphenols) that cause fruit browning. The amino acid tyrosine contains a single phenolic ring that may be oxidised by the action of PPOs to form o-quinone. Hence, PPOs may also be referred to as tyrosinases. Common foods producing the enzyme include mushrooms (Agaricus bisporus), apples (Malus domestica), avocados (Persea americana), banana (Musa (genus)), and lettuce (Lactuca sativa). Fruits high in flavan-3-ols, but low in PPOs (notably berries), are commonly combined with banana in smoothies, resulting in reduced bioavailability of flavan-3-ols and other polyphenols.
Undernutrition adversely affects the cognitive development of children, contributing to poor earning capacity and poverty in adulthood. The development of childhood undernutrition coincides with the introduction of complementary weaning foods which are usually nutrient deficient. The World Health Organization estimated in 2008 that malnutrition accounted for 54 percent of child mortality worldwide, about 1 million children. There is a strong association between undernutrition and child mortality. Another estimate in 2008 also by WHO stated that childhood underweight was the cause for about 35% of all deaths of children under the age of five years worldwide. Over 90% of the stunted children below five years of age live in sub-Saharan Africa and South Central Asia. Although access to adequate food and improving nutritional intake is an obvious solution to tackling undernutrition in children, the progress in reducing children undernutrition has been disappointing.
Fully annexed localities (Auteuil, Batignolles-Monceau, Belleville, Bercy, Charonne, Grenelle, La Chapelle, La Villette, Montmartre, Passy, and Vaugirard): Everything disappeared along with the registers of the Parisian arrondissements—both originals and duplicates. Partially annexed localities (Aubervilliers, Bagnolet, Clichy, Gentilly, Ivry, Montrouge, Neuilly, Pantin, Le Pré-Saint-Gervais, Saint-Mandé, Saint-Ouen, and Vanves) or non-annexed areas (the rest of what is today known as the Petite Couronne): The originals, having been preserved locally, are still accessible in municipal archives unless transferred to the Departmental Archives of Hauts-de-Seine, Seine-Saint-Denis, or Val-de-Marne. The duplicates, however, were destroyed, except for the decennial tables covering 1793–1859.
Usually, an enzyme molecule has only one active site, and the active site fits with one specific type of substrate. An active site contains a binding site that binds the substrate and orients it for catalysis. The orientation of the substrate and the close proximity between it and the active site is so important that in some cases the enzyme can still function properly even though all other parts are mutated and lose function. Initially, the interaction between the active site and the substrate is non-covalent and transient. There are four important types of interaction that hold the substrate in a defined orientation and form an enzyme-substrate complex (ES complex): hydrogen bonds, van der Waals interactions, hydrophobic interactions and electrostatic force interactions. The charge distribution on the substrate and active site must be complementary, which means all positive and negative charges must be cancelled out. Otherwise, there will be a repulsive force pushing them apart. The active site usually contains non-polar amino acids, although sometimes polar amino acids may also occur. The binding of substrate to the binding site requires at least three contact points in order to achieve stereo-, regio-, and enantioselectivity. For example, alcohol dehydrogenase which catalyses the transfer of a hydride ion from ethanol to NAD+ interacts with the substrate methyl group, hydroxyl group and the pro-(R) hydrogen that will be abstracted during the reaction.
Sources: en.wikipedia.org
Ile-(C=O)O− + Lys-NH3+ → Ile-(C=O)NH-Lys + H2O Isopeptide bond formation is typically enzyme-catalyzed. The reaction between lysine and glutamine, as shown above, is catalyzed by a transglutaminase. Another example of enzyme-catalyzed isopeptide bond formation is the formation of the glutathione molecule. Glutathione, a tripeptide, contains a normal peptide bond (between cysteine and glycine) and an isopeptide bond (between glutamate and cysteine). The formation of the isopeptide bond between the γ-carboxyl group of glutamate and the α-amino group of cysteine is catalyzed by the enzyme γ-glutamylcysteine synthetase. The isopeptide bond is formed instead of a eupeptide bond because intracellular peptidases are unable to recognize this linkage and therefore do not hydrolyze the bond. An isopeptide bond can form spontaneously as observed in the maturation of the bacteriophage HK97 capsid. In this case, the ε-amino group of lysine autocatalytically reacts with the side chain carboxamide group of asparagine. Spontaneous isopeptide bond formation between lysine and asparagine also occurs in Gram-positive bacterial pili.
Nando's opened its first restaurant location within the United States in Washington, D.C. in 2008. After opening more outlets within the Washington metropolitan area, it expanded into the Chicago metropolitan area, opening its first outlet on 20 May 2015 within the metro area. As of February 2026, there are 46 restaurant outlets in five states and the District of Columbia: 12 in Illinois, six in Washington, D.C., 10 in Maryland, 11 in Virginia, two in Georgia, and five in Texas.
=== Catholic === American Order of United Catholics - Founded in January 1896 in New York City by Catholics who wished to counter the influence of the American Protective Association. It was "expected of the founders" that they would demand candidates for office who disapproved of the APA or other organizations that sought to discriminate against Catholics. A Supreme Council was organized on March 7, 1896, and the Order was organized "upon the usual secret society lines". They issued a circular that proclaimed that the Church did not oppose secret societies, except those that were oathbound. Catholic Aid Association - Founded in 1878 by German Catholics in Minnesota. The order began with 464 members from 10 parishes and was called the Deutsche Römisch-Katholische Unterstützungs-Gesellschaft von Minnesota; adopted its present name in 1923. Had 58,722 members in 1965, and approximately 78,000 in 1979. Headquarters in St. Paul, Minnesota. Local groups are called "subordinate Councils", of which there were 240 in 1979. Annual convention called the "Grand Council". Has rituals for initiation, installation of officers, and other purposes. Open to Roman Catholics 16-65 who are not a member of a secret society condemned by the Church. Sponsors matching grants program for Catholic elementary schools and religious education programs. Also, a College Tuition Scholarship Program has helped 800 CAA members receive degrees. Also sponsors banquets, family outings, dances, and youth activities; now Catholic United Financial.
Deionized water (DI water, DIW or de-ionized water), often synonymous with demineralized water/DM water, is water that has had almost all of its mineral ions removed, such as cations like sodium, calcium, iron, and copper, and anions such as chloride and sulfate. Deionization is a chemical process that uses specially manufactured ion-exchange resins, which exchange hydrogen and hydroxide ions for dissolved minerals, and then recombine to form water. Because most non-particulate water impurities are dissolved salts, deionization produces highly pure water that is generally similar to distilled water, with the advantage that the process is quicker and does not build up scale. However, deionization does not significantly remove uncharged organic molecules, viruses, or bacteria, except by incidental trapping in the resin. Specially made strong base anion resins can remove Gram-negative bacteria. Deionization can be done continuously and inexpensively using electrodeionization. Three types of deionization exist: co-current, counter-current, and mixed bed.
Sigma-Aldrich Fine Chemicals (SAFC) is the fine chemical supply branch of Sigma-Aldrich specializing in raw materials for cell culture products; customized services for raw materials, manufacturing of active pharmaceutical ingredients. Sigma Life Science provides products such as custom DNA/RNA oligos; custom DNA and LNA probes; siRNA; isotopically-labelled peptides and peptide libraries. Sigma Advanced Genetic Engineering (SAGE) Labs was a division within Sigma-Aldrich that specializes in genetic manipulation of in vivo systems for special research and development applications. It was formed in 2008 to investigate zinc finger nuclease technology and its application for disease research models. Located in St. Louis, Missouri, SAGE Labs have developed knockout rats for the study of human diseases and disorders (such as autism), which are sold for up to US$95,000. SAGE also announced its first successful effort in creating a "knockout rabbit". Its facilities include a specific pathogen free, biosecure vivarium as well as research and development labs. SAGE Labs was acquired by Horizon Discovery Group in 2014. Carbolabs produces research quantities of chemicals produced by phosgenation reactions. The company was acquired in 1998. BioReliance provides testing and manufacturing services to pharmaceutical and biopharmaceutical companies that span the product cycle from early pre-clinical development to licensed production. The company was acquired by Sigma Aldrich in January 2012.
Sources: en.wikipedia.org
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.
No. Epithalamin is a heterogeneous extract containing many peptides, while epitalon is a single synthesised tetrapeptide. Publications sometimes treat findings from the two as equivalent, which is a common source of confusion. Their compositions differ and they are not interchangeable in analytical terms.
Most published work uses cell cultures or rodents because those models are faster and less costly to run. The few human trials that have been reported are small, and several lack control groups or blinding. This restricts what can reasonably be concluded about effects in people.
Reversed-phase high-performance liquid chromatography with ultraviolet detection at 214 nanometres is the usual approach. Peak area percentage provides a purity figure relative to other components in the sample. Mass spectrometry is then applied to confirm identity.