Epitalon raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-11-10 and is reviewed periodically as new material appears.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Free acid form of the tetrapeptide |
| Molecular mass | About 390.35 Da | Calculated monoisotopic value |
| Appearance | White to off-white powder | Typical lyophilized presentation |
| Solubility | Soluble in water | Also dissolves in buffered saline |
| Storage temperature | Minus 20 degrees Celsius | Dry, dark conditions; avoid repeated thawing |
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.
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.
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.
To determine saponification value, the sample is treated with an excess of alkali (usually an ethanolic solution of potassium hydroxide) for half an hour under reflux. The KOH is consumed by reaction with triglycerides, which consume three equivalents of base. Diglycerides consume two equivalents of KOH. Monoglycerides and free fatty acids, as well as other esters such as lactones, consume one equivalent of base. At the end of the reaction the quantity of KOH is determined by titration using standard solution of hydrochloric acid (HCl). Key to the method is the use of phenolphthalein indicator, which indicates the consumption of strong base (KOH) by the acid, not the weak base (potassium carboxylates). The SV (mg KOH/ g of sample) is calculated as following: Eq. 1 where: B {\displaystyle {\textrm {B}}} is the volume of HCl solution used for the blank run, in mL; S {\displaystyle {\textrm {S}}} is the volume of HCl solution used for the tested sample, in mL; M {\displaystyle {\textrm {M}}} is the molarity of HCl solution, in mol / L; 56.1 is the molecular weight of KOH, in g / mol; W
12(S)-HETE, 12(S)-HpETE, and with far less potency 12(R)-HETE reduced insulin secretion and caused apoptosis in cultured human pancreatic insulin-secreting beta cell lines and prepared pancreatic islets. TNFα, IL-1β, and IFNγ also reduced insulin secretion in cultured human pancreatic INS-1 beta cells, apparently by inducing the expression of NOX1 (NADPH oxidase 1) and thereby to the production of cell-toxic reactive oxygen species; these cytokine effects were completely dependent on 12-lipoxygenase and mimicked by 12(S)-HETE but not 12(R)-HETE. 12-lipoxygenase-knockout mice (i.e., mice genetically manipulated to remove the Alox12, i.e. 12-lipoxygenase gene, see Lipoxygenase
The Oculus Rift announcement led to other VR developments. Sony Computer Entertainment developed the PlayStation VR system for the PlayStation 4, while Valve partnered with HTC to develop the HTC Vive; both of these units were released in 2016. Valve later developed their own headset without HTC, the Valve Index, which was released in 2019.
Sources: en.wikipedia.org
Peritonitis is the inflammation of the peritoneum. It is more commonly associated to infection from a punctured organ of the abdominal cavity. It can also be provoked by the presence of fluids that produce chemical irritation, such as gastric acid or pancreatic juice. Peritonitis causes fever, tenderness, and pain in the abdominal area, which can be localized or diffuse. The treatment involves rehydration, administration of antibiotics, and surgical correction of the underlying cause. Mortality is higher in the elderly and if present for a prolonged time.
The Mojave rattlesnake is widely regarded as producing one of the most toxic snake venoms in the New World, based on LD50 studies in laboratory mice. Their potent venom is the result of a presynaptic neurotoxin composed of two distinct peptide subunits. The basic subunit (a phospholipase A2) is mildly toxic and apparently rather common in North American rattlesnake venoms. The less common acidic subunit is not toxic by itself, but in combination with the basic subunit, produces the potent neurotoxin called "Mojave toxin". Nearly identical neurotoxins have been discovered in five North American rattlesnake species besides the Mojave rattlesnake. However, not all populations express both subunits. The venom of many Mojave rattlesnakes from south-central Arizona lacks the acidic subunit and has been designated "venom B", while Mojave rattlesnakes tested from all other areas express both subunits and have been designated "venom A" populations.
=== Radiology === Radiologically, the main feature required for a confident diagnosis of UIP is honeycomb change in the periphery and the lower portions (bases) of the lungs. On high-resolution computed tomography (HRCT), the following categories, depending on imaging findings, have been recommended by a collaborative effort by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and the Latin American Thoracic Society:
Sources: en.wikipedia.org
== Assault charge == In August 2011, Hibbered was charged with assault after he punched and knocked a man out in Mornington on 31 July. He pleaded guilty to the charges in September and escaped conviction, but received a $2500 fine.
Observe the value of the friction factor for laminar flow at a Reynolds number of 1000. If the value of the friction factor is 0.064, then the Darcy friction factor is plotted in the Moody diagram. Note that the nonzero digits in 0.064 are the numerator in the formula for the laminar Darcy friction factor: fD = 64/Re. If the value of the friction factor is 0.016, then the Fanning friction factor is plotted in the Moody diagram. Note that the nonzero digits in 0.016 are the numerator in the formula for the laminar Fanning friction factor: f = 16/Re. The procedure above is similar for any available Reynolds number that is an integer power of ten. It is not necessary to remember the value 1000 for this procedure—only that an integer power of ten is of interest for this purpose.
Alongside many domestic obligations, more than 3,000 Canadian Armed Forces (CAF) personnel are deployed in multiple foreign military operations. The Canadian unified forces comprise the Royal Canadian Navy, Canadian Army, and Royal Canadian Air Force. The nation employs a professional, volunteer force of approximately 68,000 active personnel and 27,000 reserve personnel. Canada will spend 2% of its GDP on defence by the 2026 fiscal year, up from 1.3% and 1.4% in previous years. Peacekeeping is deeply embedded in Canadian culture and a distinguishing feature that Canadians feel sets their foreign policy apart from the United States. Canada has long been reluctant to participate in military interventions that are not sanctioned by the United Nations, such as the Vietnam War, the 2003 invasion of Iraq and the 2026 Iran war. Since the 21st century, Canadian direct participation in UN peacekeeping efforts has greatly declined. The large decrease was a result of Canada directing its participation to UN-sanctioned military operations through the North Atlantic Treaty Organization, rather than directly through the UN. The change to participation via NATO has resulted in a shift towards more militarized and deadly missions rather than traditional peacekeeping duties.
5-MeO-DMT Bufotenine crack cocaine dimethyltryptamine (DMT) DiPT methamphetamine Methaqualone phencyclidine (PCP) synthetic cannabinoids (see also: synthetic cannabis) many others, including some prescription drugs
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.
No naturally occurring free form of the peptide has been described. The four-amino-acid sequence can appear as a fragment within larger proteins, but that is not the same as the intact compound being present as a circulating molecule. Materials used in research are synthetic.
Purity is usually checked by reverse-phase high-performance liquid chromatography, which separates the target peptide from related impurities. Mass spectrometry is commonly used alongside it to confirm molecular mass. Some suppliers also provide amino acid analysis for additional sequence confirmation.
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.