AEDG 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 2026-03-24 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.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
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 |
|---|---|---|
| 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 |
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
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=== Medicine === Dozens of congenital metabolic diseases also known as inborn errors of metabolism (IEM) are now detectable by newborn screening tests, especially the testing using gas chromatography–mass spectrometry. GC–MS can determine compounds in urine even in minor concentration. These compounds are normally not present but appear in individuals suffering with metabolic disorders. This is increasingly becoming a common way to diagnose IEM for earlier diagnosis and institution of treatment eventually leading to a better outcome. It is now possible to test a newborn for over 100 genetic metabolic disorders by a urine test at birth based on GC–MS. In combination with isotopic labeling of metabolic compounds, the GC–MS is used for determining metabolic activity. Most applications are based on the use of 13C as the labeling and the measurement of 13C-12C ratios with an isotope ratio mass spectrometer (IRMS); an MS with a detector designed to measure a few select ions and return values as ratios.
Other conditions that can cause similar symptoms to a migraine headache include temporal arteritis, cluster headaches, acute glaucoma, meningitis and subarachnoid hemorrhage. Temporal arteritis typically occurs in people over 50 years old and presents with tenderness over the temple. Cluster headache presents with one-sided nose stuffiness, tears, and severe pain around the eyes. Acute glaucoma is associated with vision problems. Meningitis is associated with fever. Subarachnoid hemorrhage is associated with a very fast onset. Tension headaches typically occur on both sides, are not pounding, and are less disabling. Those with stable headaches that meet criteria for migraine should not receive neuroimaging to look for other intracranial disease.
=== Protein cleavage === Cyanogen bromide hydrolyzes peptide bonds at the C-terminus of methionine residues. This reaction is used to reduce the size of polypeptide segments for identification and sequencing.
Sources: en.wikipedia.org
Enocyanin is a natural colorant extracted from the peels of black grapes (primarily Vitis vinifera). It is a mixture composed primarily of anthocyanins, particularly malvidin-3-glucoside (C23H25O12+). It is part of the water-soluble pigments belonging to the flavonoid class.
The prolactin-releasing peptide receptor (PrRPR) also known as G-protein coupled receptor 10 (GPR10) is a protein that in humans is encoded by the PRLHR gene. PrRPR is a G-protein coupled receptor that binds the prolactin-releasing peptide (PRLH).
== Coaching == In 1993, the Milwaukee Brewers named Epstein manager of the rookie league Helena Brewers, who played in the Pioneer League. He only managed 11 games, as his hitting philosophy learned under Ted Williams was contrary to the current trend at the time.
=== Pharmacodynamics === KNX-100 produces oxytocin-like effects, such as pro-social, anti-aggressive, and anti-addictive effects among others, in rodents and monkeys. The drug reduced self-administration of methamphetamine in rats by 85%, of cocaine in rhesus monkeys by 90%, and of alcohol in baboons by more than 50%. It is thought that KNX-100 may produce its antiaddictive effects by discounting drug reward in favor of social reward. In addition to its antiaddictive effects, KNX-100 reduces opioid withdrawal and nicotine withdrawal symptoms in animals. It appears to act to reduce opioid withdrawal symptoms by suppressing increased dynorphin/κ-opioid receptor signaling in the nucleus accumbens shell. Unexpectedly, KNX-100 did not show affinity for the oxytocin receptor nor act as an agonist, antagonist, or positive allosteric modulator of the receptor, but nonetheless robustly activates oxytocinergic signaling. In fact, KNX-100 can activate oxytocinergic signaling and cause associated effects to a greater extent than oxytocin itself. Screening at more than 100 different receptors and transporters was initially unable to identify the drug's biological target. It was suggested that KNX-100 may be acting at an upstream target to indirectly modulate the oxytocin system and increase oxytocin production. Subsequently, KNX-100 was said by its developers to have a novel undisclosed mechanism of action.
Cigarette companies have capitalized on this philosophical objection and exploited the doubts of clinicians, who consider only individual cases, on the causal link in the stochastic expression of the toxicity as an actual disease. There have been multiple court cases against tobacco companies for having researched the health effects of smoking, but having then suppressed the findings or formatted them to imply lessened or no hazard. After a ban on smoking in all enclosed public places was introduced in Scotland in March 2006, there was a 17 per cent reduction in hospital admissions for acute coronary syndrome during the ten months after the ban, compared with the ten preceding months.
Sources: en.wikipedia.org
=== 4 May === Explosions were reported in Kyiv and Odesa in another series of Russian air attacks. Ukraine claimed to have destroyed 18 out of the 24 drones launched, plus a reconnaissance drone, with only light damage to property; the drones were marked with messages such as "For Moscow" and "For the Kremlin". According to TASS, Ukrainian drones attacked and set ablaze the Ilsky refinery near Novorossiisk. The fire was extinguished without damage after two hours. Fighting broke out between Russian and Ukrainian delegates to the Parliamentary Assembly of the Black Sea Economic Cooperation in Ankara, Turkey. Ukrainian delegates had earlier waved Ukrainian flags during a speech by a Russian delegate. Later, Oleksandr Marikovski, a Ukrainian MP, physically assaulted a Russian official after the latter seized his flag. Ukraine for the first time intercepted a Russian Kh-47M2 Kinzhal hypersonic missile, following reports from Kyiv of a powerful explosion overnight. The Ukrainian Air Force said they shot it down using the Patriot missile system protecting the capital.
==== Three-dimensional structure ==== The three-dimensional structure of heparin is complicated because iduronic acid may be present in either of two low-energy conformations when internally positioned within an oligosaccharide. The conformational equilibrium is influenced by the sulfation state of adjacent glucosamine sugars. Nevertheless, the solution structure of a heparin dodecasaccharide composed solely of six GlcNS(6S)-IdoA(2S) repeat units has been determined using a combination of NMR spectroscopy and molecular modeling techniques. Two models were constructed, one in which all IdoA(2S) were in the 2S0 conformation (A and B below), and one in which they are in the 1C4 conformation (C and D below). However, no evidence suggests that changes between these conformations occur in a concerted fashion. These models correspond to the protein data bank code 1HPN.
The physics of FTICR is similar to that of a cyclotron at least in the first approximation. In the simplest idealized form, the relationship between the cyclotron frequency and the mass-to-charge ratio is given by
Note: Other substances once thought to be vitamins were given B-numbers, but were disqualified once discovered to be either manufactured by the body or not essential for life. See § Related compounds for numbers 4, 8, 10, 11, and others.
== Overview == A chaotropic agent is a substance which disrupts the structure of, and denatures, macromolecules such as proteins and nucleic acids (e.g. DNA and RNA). Chaotropic solutes increase the entropy of the system by interfering with intermolecular interactions mediated by non-covalent forces such as hydrogen bonds, van der Waals forces, and hydrophobic effects. Macromolecular structure and function is dependent on the net effect of these forces (see protein folding), therefore it follows that an increase in chaotropic solutes in a biological system will denature macromolecules, reduce enzymatic activity and induce stress on a cell (i.e., a cell will have to synthesize stress protectants). Tertiary protein folding is dependent on hydrophobic forces from amino acids throughout the sequence of the protein. Chaotropic solutes decrease the net hydrophobic effect of hydrophobic regions because of a disordering of water molecules adjacent to the protein. This solubilises the hydrophobic region in the solution, thereby denaturing the protein. This is also directly applicable to the hydrophobic region in lipid bilayers; if a critical concentration of a chaotropic solute is reached (in the hydrophobic region of the bilayer) then membrane integrity will be compromised, and the cell will lyse. Chaotropic salts that dissociate in solution exert chaotropic effects via different mechanisms.
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.
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.