Epitalon is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-11-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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 |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Linear tetrapeptide, also written AEDG |
| Molecular mass | About 390.35 g/mol | Value calculated from the sequence |
| Appearance | White to off-white powder | Lyophilised material forms a loose cake |
| Solubility | Freely soluble in water | Also dissolves in isotonic saline |
| Storage | -20 °C, desiccated | Aliquot solutions to avoid freeze–thaw cycling |
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.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
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.
== External links == AGSD. - Association for Glycogen Storage Disease. A US-based non-profit, parent and patient oriented support group dedicated to promoting the best interest of all the different types of glycogen storage disease. AGSD-UK - Association for Glycogen Storage Disease (UK). A UK-based charity which helps individuals and families affected by Glycogen Storage Disease by putting people in contact, providing information and support, publishing a magazine and holding conferences, workshops, courses and family events. IamGSD - International Association for Muscle Glycogen Storage Disease. A non-profit, patient-led international group encouraging efforts by research and medical professionals, national support groups and individual patients worldwide. IPA - International Pompe Association. (Pompe Disease is also known as GSD-II). A non-profit, federation of Pompe disease patient's groups world-wide. It seeks to coordinate activities and share experience and knowledge between different groups. EUROMAC - EUROMAC is a European registry of patients affected by McArdle Disease and other rare neuromuscular glycogenoses. CoRDS - Coordination of Rare Diseases at Sanford (CoRDS) is a centralized international patient registry for all rare diseases. They work with patient advocacy groups, including IamGSD, individuals and researchers. CORD - Canadian Organization for Rare Disorders (CORD) is a Canadian national network for organizations representing all those with rare disorders.
Treating Type 2 Diabetes with glucose mimetics Mason found the common denominator between gastric and intestinal bypass when treating type 2 diabetes in 1998. The exposure of the distal bowel to glucose or other stimulants such as glucose mimetics resulted in the secretion of GLP-1 (glucagon-like peptide-1) hormones, which could potentially treat diabetes type-2 disease. Gastric bypass surgery treated type-2 diabetes through weight loss and the release of GLP-1 hormones. To treat diabetes-type 2 patients without surgery, he thought that using a form of glucose substitute or glucose mimetic that would reach the distal ileum before it was absorbed could be a simple and cost-effective treatment. He suggested using glucose mimetic d-tagatose in addition to weight reduction with a proper diet and increased physical activity.
=== Meckel's diverticulum === Pertechnetate is actively accumulated and secreted by the mucoid cells of the gastric mucosa, and therefore, technetate(VII) radiolabeled with Tc99m is injected into the body when looking for ectopic gastric tissue as is found in a Meckel's diverticulum with Meckel's Scans.
Medical preparations of insulin mix the peptide hormone with preservatives that adjust the pH and delay denaturation and absorption. Insulin analogues retain the hormone's function while providing improved absorption and biochemical activity. characteristics not currently possible with subcutaneously injected insulin proper. Insulin lispro, insulin aspart, and insulin glulisine are analogues that are rapidly absorbed to mimic real beta cell-produced insulin, while insulin detemir and insulin glargine are steadily absorbed to avoid a rapid decline in insulin action. However, meta-analyses conducted by Cochrane in 2005, Germany's Institute for Quality and Cost Effectiveness in the Health Care Sector [IQWiG] in 2007, and Canadian Agency for Drugs and Technology in Health (CADTH) also in 2007 have consistently shown that insulin analogues provide no clinical advantage over conventional insulin. However, insulin analogues are more temperature-resistant than human insulin, so they are preferred for clinical use in regions with limited refrigeration and extreme heat. Commonly used types of insulin are differentiated by the speed of their biochemical activity. Fast/rapid-acting insulin includes insulin analogues aspart, lispro, and glulisine. These begin to work within 5 to 15 minutes and are active for 3 to 4 hours. Most insulins form hexamers, which delay entry into the blood in active form; these analog insulins do not but have normal insulin activity.
== Structure == Most sv-LAAOs are reported as being homodimers with multiple subunits that have molecular weights around 50–70 kDa and the interaction between the subunits occurs via non-covalent interactions. Sv-LAAOs are present in the acidic, basic, and neutral forms of the protein. Studies that look at x-ray crystal structures have confirmed that sv-LAAOs are often found as functional dimers, with each dimer having three domains. The three domains are the substrate-binding site, FAD-binding site, and a helical domain. The substrate-binding site lies at the bottom of a funnel-shaped cavity approximately 25 Å deep, enabling substrate specificity among sv-LAAOs. Structural differences in active site topology likely account for species-dependent substrate preferences. Additionally, LAAOs are thermolabile, with cold inactivation and heat reactivation properties, necessitating specific storage and pre-activation conditions to preserve enzymatic activity. It has also been determined that the FAD prosthetic group becomes deeply entrenched in the enzyme structure, which allows for pervasive interactions with both neighboring atoms and conserved water molecules. Additionally, this flavin-containing prosthetic group has been classified as providing snake venom with its quintessential dark yellow coloration, which is shown in Figure 2. One unusual characteristic reported for sv-LAAOs regards the cold inactivation and heat reactivation properties of the protein. Thereby, most sv-LAAOs are considered to be thermolabile enzymes.
Sources: en.wikipedia.org
Allison's attempts at developing a high-altitude engine were underfunded, but produced the V-1710-45, which featured a variable-speed auxiliary supercharger and developed 1,150 horsepower (860 kW) at 22,400 feet (6,800 m). In November 1941, NAA studied the possibility of using it, but fitting its excessive length in the Mustang would require extensive airframe modifications and cause long production delays. In May 1942, following positive reports from the RAF on the Mustang I's performance below 15,000 ft, Ronald Harker, a test pilot for Rolls-Royce, suggested fitting a Merlin 61, as fitted to the Spitfire Mk IX. The Merlin 61 had a two-speed, two-stage, intercooled supercharger, designed by Stanley Hooker of Rolls-Royce. Both the Merlin 61 and V-1710-39 were capable of about 1,570 horsepower (1,170 kW) war emergency power at relatively low altitudes, but the Merlin developed 1,390 horsepower (1,040 kW) at 23,500 feet (7,200 m) versus the Allison's 1,150 horsepower (860 kW) at 11,800 feet (3,600 m), delivering an increase in top speed from 390 mph (340 kn; 630 km/h) at ~15,000 feet (4,600 m) to an estimated 440 mph (380 kn; 710 km/h) at 28,100 feet (8,600 m). In the end the Merlin 61 was never fitted to the Mustang X, (or any other Mustang). The 65 series (a medium altitude engine) was fitted to all Mustang X prototypes. Initially, the Mustang's steadfast champion, USAAC/F Assistant Air Attaché Major Thomas Hitchcock, was concerned that the USAAF had little or no interest in the potential of the P-51A and its development with the Merlin engine.
== External links == Gerngross TU, Slater SC (August 2000). "How green are green plastics?". Sci. Am. 283 (2): 37–41. Bibcode:2000SciAm.283b..36G. doi:10.1038/scientificamerican0800-36. PMID 10914397. Plastics from plants called costly (CNN) Tillman Gerngross Faculty Page at Dartmouth About Adimab LLC.
== Use in production engines == UK company RCV Engines Ltd uses rotating cylinder liner technology as a specialized form of rotary valve in some of their four-stroke model engine and small-engine line-up. RCV also use horizontal and vertical rotary valves in four-stroke engines in their current range of engines. Piccard-Pictet in Switzerland patented a Rotary Valve, GB118407, basically a turning cylinder liner, different to Burt-McCollum Single Sleeve valve that both oscilates and turns, in an ellipsoid way RCV have developed a 125cc rotating cylinder liner engine, incorporating a rotating valve in the cylinder liner, for scooter applications. PGO Scooters of Taiwan were working with RCV in developing the engine for their applications. The Suzuki RG500 "Gamma" was powered by a two-stroke, rotary valve, twin crank, square four engine displacing 498 cubic centimeters. The power output was 93.7 brake horsepower (69.9 kW) at 9,500 RPM.
Russia's Federal Security Service (FSB) claimed to have intercepted 70 kilograms of RDX, an RPG-7 and other bomb-making material at a border crossing in Pskov Oblast from Latvia. Originating from Ukraine, the paperwork indicated that it travelled through several EU countries before reaching the Russian border. The weapons were discovered hidden in Orthodox religious icons and paraphernalia.
Sources: en.wikipedia.org
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.
AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.
Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.
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.