AEDG raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
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.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
The proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
The most frequently cited proposed action is induction of telomerase, the enzyme that adds repeat sequences to chromosome ends. Cell-culture work from the originating group reported higher telomerase reverse transcriptase expression and measurable telomere elongation in human somatic cells after exposure. How a four-residue peptide would reach nuclear gene regulation is not established, and no cell-surface receptor or uptake route has been identified. Additional reports describe changes in melatonin secretion, antioxidant enzyme activity and lipid peroxidation in aged animals, but these findings remain mechanistically unconnected to the telomerase observation.
Published evidence comes mainly from Russian-language journals and from a single research group, with small sample sizes and limited independent replication. A few laboratories outside that group have examined related peptides and reported weaker or absent telomerase effects, so the central claim is best described as contested rather than settled. Rodent studies report modest changes in some ageing markers and in survival, but designs vary and control conditions are often sparse. No large randomised trial in humans has been published, and long-term safety data in healthy populations are correspondingly thin.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
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.
=== Solubility === Carboxylic acids are polar. Because they are both hydrogen-bond acceptors (the carbonyl −C(=O)−) and hydrogen-bond donors (the hydroxyl −OH), they also participate in hydrogen bonding. Together, the hydroxyl and carbonyl group form the functional group carboxyl. Carboxylic acids usually exist as dimers in nonpolar media due to their tendency to "self-associate". Smaller carboxylic acids (1 to 5 carbons) are soluble in water, whereas bigger carboxylic acids have limited solubility due to the increasing hydrophobic nature of the alkyl chain. These longer chain acids tend to be soluble in less-polar solvents such as ethers and alcohols. Aqueous sodium hydroxide and carboxylic acids, even hydrophobic ones, react to yield water-soluble sodium salts. For example, enanthic acid has a low solubility in water (0.2 g/L), but its sodium salt is very soluble in water.
The Scud missiles targeting Israel were relatively ineffective, as firing at extreme range resulted in a dramatic reduction in accuracy and payload. Two Israeli civilians died as a direct result of the missile attacks. Between 11 and 74 died from incorrect use of gas masks, heart attacks, and incorrect use of the anti-chemical weapons drug atropine. Approximately 230 Israelis were injured. Extensive property damage was also caused, and, according to the Israel Ministry of Foreign Affairs, "Damage to general property consisted of 1,302 houses, 6,142 apartments, 23 public buildings, 200 shops and 50 cars." It was feared that Iraq would fire missiles filled with nerve agents such as sarin. As a result, Israel's government issued gas masks to its citizens. When the first Iraqi missiles hit Israel, some people injected themselves with an antidote for nerve gas. It has been suggested that the sturdy construction techniques used in Israeli cities, coupled with the fact that Scuds were only launched at night, played an important role in limiting the number of casualties from Scud attacks.
OPD (o-phenylenediamine dihydrochloride) turns amber to detect HRP (horseradish peroxidase), which is often used to as a conjugated protein. TMB (3,3',5,5'-tetramethylbenzidine) turns blue when detecting HRP and turns yellow after the addition of sulfuric or phosphoric acid. ABTS (2,2'-Azinobis [3-ethylbenzothiazoline-6-sulfonic acid]-diammonium salt) turns green when detecting HRP. PNPP (p-Nitrophenyl Phosphate, Disodium Salt) turns yellow when detecting alkaline phosphatase.
Haloxazolam (marketed in Japan under the brand name Somelin), is a drug which is a benzodiazepine derivative. It has similar hypnotic properties as the benzodiazepine drugs triazolam, temazepam, and flunitrazepam and as such is indicated for the treatment of insomnia. A study in cats comparing estazolam and haloxazolam found that haloxazolam only affects gamma motor neurons, whereas estazolam affects both alpha and gamma motor neurons. Chemically, it is an oxazolobenzodiazepine.
The Mazda MX-5 was developed around the same time in the US, but had tried to imitate the 1960s Lotus Elan. How Naoki Sakai originated the Italian-heritage Nissan Figaro in the early 1990s - the car, made for Japanese women in a limited production, became so popular that it had to be sold by lottery. How the Mazda research centre at Kanagawa-ku, Yokohama was making intelligent cars.
Sources: en.wikipedia.org
The formyl peptide receptors (FPR) belong to a class of G protein-coupled receptors involved in chemotaxis. In humans, there are three formyl peptide receptor isoforms, each encoded by a separate gene that are named FPR1, FPR2, and FPR3. These receptors were originally identified by their ability to bind N-formyl peptides such as N-formylmethionine produced by the degradation of either bacterial or host cells. Hence formyl peptide receptors are involved in mediating immune cell response to infection. These receptors may also act to suppress the immune system under certain conditions. The close phylogenetic relation of signaling in chemotaxis and olfaction was recently proved by detection formyl peptide receptor like proteins as a distinct family of vomeronasal organ chemosensors in mice. FPR is now properly accepted as termed FPR1 by the International Union of Basic and Clinical Pharmacology.
These studies both reported that all obvious symptoms of scurvy could be completely reversed by supplementation of only 10 mg a day. Treatment of scurvy can be with vitamin C-containing foods or dietary supplements or injection.
Topical beta-adrenergic receptor antagonists, such as timolol, levobunolol, and betaxolol, decrease aqueous humor production by the epithelium of the ciliary body. Alpha2-adrenergic agonists, such as brimonidine and apraclonidine, work by a dual mechanism, decreasing aqueous humor production and increasing uveoscleral outflow. Less-selective alpha agonists, such as epinephrine, decrease aqueous humor production through vasoconstriction of ciliary body blood vessels, useful only in open-angle glaucoma. Epinephrine's mydriatic effect, however, renders it unsuitable for closed-angle glaucoma due to further narrowing of the uveoscleral outflow (i.e., further closure of the trabecular meshwork, which is responsible for the absorption of aqueous humor). Miotic agents (parasympathomimetics), such as pilocarpine, work by contraction of the ciliary muscle, opening the trabecular meshwork and allowing increased outflow of the aqueous humor. Echothiophate, an acetylcholinesterase inhibitor, is used in chronic glaucoma. Carbonic anhydrase inhibitors, such as dorzolamide, brinzolamide, and acetazolamide, lower secretion of aqueous humor by inhibiting carbonic anhydrase in the ciliary body. Each of these medicines may have local and systemic side effects. Wiping the eye with an absorbent pad after the administration of eye drops may result in fewer adverse effects. Initially, glaucoma drops may reasonably be started in either one or in both eyes.
=== Plant glutamate cysteine ligase === The plant glutamate cysteine ligase is a redox-sensitive homodimeric enzyme, conserved in the plant kingdom. In an oxidizing environment, intermolecular disulfide bridges are formed and the enzyme switches to the dimeric active state. The midpoint potential of the critical cysteine pair is -318 mV. In addition to the redox-dependent control, the plant GCL enzyme is feedback inhibited by glutathione. GCL is exclusively located in plastids, and glutathione synthetase (GS) is dual-targeted to plastids and cytosol, thus GSH and gamma-glutamylcysteine are exported from the plastids. Studies also shown that restricting GCL activity to the cytosol or glutathione biosynthesis to the plastids is sufficient for normal plant development and stress tolerance. Both glutathione biosynthesis enzymes are essential in plants; knock-outs of GCL and GS are lethal to embryo and seedling, respectively. As of late 2007, six structures have been solved for this class of enzymes, with PDB accession codes PDB: 1V4G, PDB: 1VA6, PDB: 2D32, PDB: 2D33, PDB: 2GWC, and PDB: 2GWD.
Sources: en.wikipedia.org
==== Cingulatan research ==== Casali et al. (2026) study the phylogenetic affinities of armadillos and their extinct relatives. Redescription of the holotype of Asterostemma barrealense (reinterpreted as an indeterminate member of Propalaehoplophorini) and description of a new glyptodont specimen from the Chinches Formation (San Juan Province, Argentina) assigned to the group Propalaehoplophorini is published by Martini et al. (2026). Guzmán-Gutiérrez (2026) report the discovery of fossil material of Pampatherium sp. from the Pleistocene strata from the El Cedazo creek locality, representing the first record of the genus from Aguascalientes (Mexico). Lagunas-Rodríguez et al. (2026) describe fossil material of Glyptotherium cylindricum from the Pleistocene strata from Puebla (Mexico), and interpret the presence of fossils of G. cylindricum in the Trans-Mexican Volcanic Belt and in the Sierra Madre del Sur within the State of Puebla as likely linked to the location of the corridor used by members of the species to disperse into North America. Zamorano, Vezzosi & Mones (2026) describe a caudal tube of Panochthus sp. from the Pleistocene strata (possibly Timbúes Formation) in the Santa Fe Province (Argentina) and reevaluate the validity of Panochthus florensis, considering it to be species inquirenda. Taxonomic revision of late Pliocene to Middle Pleistocene glyptodonts from central Argentina is published by Zurita et al. (2026). Sostillo et al. (2026) provide a systematic review of glyptodonts from the Quaternary strata from eastern and central La Pampa Province (Argentina).
== Occurrence == The occurrence of unsaturated fats varies widely in nature. The saturated fatty acid components are almost exclusively stearic (C18) and palmitic acids (C16). Monounsaturated fats are almost exclusively oleic acid. Linolenic acid comprises most of the triunsaturated fatty acid component.
=== Protandim voluntary recall === In December 2012, LifeVantage issued a voluntary recall of select lots (ten lots in total comprising 247,896 bottles) of Protandim due to potential health risks arising from the possible inclusion of small metal fragments in the final product. In February 2013, the company announced that it was extending the recall to include additional lots of the product, estimating the total cost of the recall at $5.9 million.
== Interactions == Blood plasma concentrations may be increased when combined with CYP3A4 inhibitors (e.g. ketoconazole, clarithromycin, ritonavir, and voriconazole) possibly leading to more side effects. This has been clinically verified for ketoconazole, which increases lurasidone exposure by a factor of 9, and is also expected for other 3A4 inhibitors such as grapefruit juice. Co-administration of CYP3A4 inducers like rifampicin, carbamazepine or St. John's wort can reduce plasma levels of lurasidone and its active metabolite, and consequently decrease the effects of the drug. For rifampicin, the reduction was sixfold in a study.
== Chemical mechanism == The carbonyl group of the sugar reacts with the amino group of the amino acid, producing N-substituted glycosylamine and water The unstable glycosylamine undergoes Amadori rearrangement, forming ketosamines Several ways are known for the ketosamines to react further: Produce two water molecules and reductones Diacetyl, pyruvaldehyde, and other short-chain hydrolytic fission products can be formed. Produce brown nitrogenous polymers and melanoidins
Sources: en.wikipedia.org
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.