If you have been reading about AEDG and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-11-22. Numbers and descriptions here follow the published literature rather than marketing material.
（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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Linear tetrapeptide | Four residues joined by three peptide bonds |
| Sequence | Ala-Glu-Asp-Gly | Commonly abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free acid form |
| Monoisotopic mass | Approximately 390 Da | Matches values reported from mass spectrometry |
| Net charge near neutral pH | Negative | Contributed by glutamate and aspartate side chains |
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.
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.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
HA (aq) + H2O (l) ⇌ H3O+ (aq) + A− (aq) Ka Common examples of monoprotic acids in mineral acids include hydrochloric acid (HCl) and nitric acid (HNO3). On the other hand, for organic acids the term mainly indicates the presence of one carboxylic acid group and sometimes these acids are known as monocarboxylic acid. Examples in organic acids include formic acid (HCOOH), acetic acid (CH3COOH) and benzoic acid (C6H5COOH).
. Special relativity also redefines the concept of mass and energy, which can be used interchangeably and are defined relative to the frame of reference. Several quantities had to be defined for consistency, such as the rest mass of a particle (mass in the rest frame of the particle) and the relativistic mass (in another frame). The latter term is usually less frequently used. In general relativity, conservation of both mass and energy is not globally conserved and its definition is more complicated.
=== Taxonomy === The species A. maxima and A. platensis were once classified in the genus Spirulina. The common name, spirulina, refers to the dried biomass of A. platensis, which belongs to photosynthetic bacteria that cover the groups Cyanobacteria and Prochlorophyta. Scientifically, a distinction exists between spirulina and the genus Arthrospira, for which the two species were originally proposed. Species of Arthrospira have been isolated from alkaline brackish and saline waters in tropical and subtropical regions. Among the various species included in the genus Arthrospira, A. platensis is the most widely distributed and is mainly found in Africa, but also in Asia. The term "spirulina" (without italicizing and usually without capitalization) remains in use for historical reasons. In 2019 it was found that the cultivated species differ too much from the type species of Arthospira to be in the genus, necessitating another batch of renaming to Limnospira to reflect biological reality.
Sources: en.wikipedia.org
===== Efficacy ===== After its launch in 2015 and marketed as Addyi, the drug experienced controversies and rejection from being acknowledged after three reviews on the clinical trials. Regarding the eligible prescription criteria concluded from the trials, the patient should have a diagnosed psychological pathology, medical comorbidities, and the presence of personal relationship issues. Despite being the first drug, its efficacy was not significant for treatment less than at least four weeks. Treatment withdrawal is also practiced if recipients do not experience improvements in symptoms after eight weeks. Nevertheless, around 18% of the gain was observed after 24 weeks of treatment.
=== Pyrimidines === Uridine phosphorylase or pyrimidine-nucleoside phosphorylase substitutes the anomeric-carbon-bonded phosphate of ribose 1-phosphate for the free base uracil, forming the nucleoside uridine. Uridine kinase (aka uridine–cytidine kinase) can then phosphorylate the 5’-carbon of this nucleoside into uridine monophosphate (UMP). UMP/CMP kinase (EC 2.7.4.14) can phosphorylate UMP into uridine diphosphate, which nucleoside diphosphate kinase can phosphorylate into uridine triphosphate. Thymidine phosphorylase or pyrimidine-nucleoside phosphorylase adds 2-deoxy-alpha-D-ribose 1-phosphate to thymine, with thymine bonding at the anomeric carbon of the deoxyribose, forming the deoxynucleoside thymidine. Thymidine kinase can then phosphorylate the 5’-carbon of this compound into thymidine monophosphate (TMP). Thymidylate kinase can phosphorylate TMP into thymidine diphosphate, which nucleoside diphosphate kinase can phosphorylate into thymidine triphosphate. The nucleosides cytidine and deoxycytidine can be salvaged along the uracil pathway by cytidine deaminase, which converts them to uridine and deoxyuridine, respectively. Alternatively, uridine–cytidine kinase can phosphorylate them into cytidine monophosphate (CMP) or deoxycytidine monophosphate (dCMP). UMP/CMP kinase can phosphorylate (d)CMP into cytidine diphosphate or deoxycytidine diphosphate, which nucleoside diphosphate kinase can phosphorylate into cytidine triphosphate or deoxycytidine triphosphate.
Plants have been engineered for scientific research, to display new flower colors, deliver vaccines, and to create enhanced crops. Many plants are pluripotent, meaning that a single cell from a mature plant can be harvested and under the right conditions can develop into a new plant. This ability can be taken advantage of by genetic engineers; by selecting for cells that have been successfully transformed in an adult plant a new plant can then be grown that contains the transgene in every cell through a process known as tissue culture. Much of the advances in the field of genetic engineering has come from experimentation with tobacco. Major advances in tissue culture and plant cellular mechanisms for a wide range of plants has originated from systems developed in tobacco. It was the first plant to be altered using genetic engineering and is considered a model organism for not only genetic engineering, but a range of other fields. As such the transgenic tools and procedures are well established making tobacco one of the easiest plants to transform. Another major model organism relevant to genetic engineering is Arabidopsis thaliana. Its small genome and short life cycle makes it easy to manipulate and it contains many homologs to important crop species. It was the first plant sequenced, has a host of online resources available and can be transformed by simply dipping a flower in a transformed Agrobacterium solution. In research, plants are engineered to help discover the functions of certain genes.
Sources: en.wikipedia.org
=== Other === Due to its naturally selective spectrum of activity, it is also employed as a selective agent in microbiological media to isolate gram-negative bacteria, yeast, and moulds. Nisin has also been used in food packaging applications and can serve as a preservative by controlled release onto the food surface from the polymer packaging. In combination with miconazole, it has been studied as a possible treatment for infections of Clostridioides difficile.
=== Pharmacodynamics === Pharmacodynamics includes enzymes for which vitamin C is a cofactor, with function potentially compromised in a deficiency state, and any enzyme cofactor or other physiological function affected by administration of vitamin C, orally or injected, in excess of normal requirements. At normal physiological concentrations, vitamin C is an enzyme substrate or cofactor and an electron donor antioxidant. The enzymatic functions include the synthesis of collagen, carnitine, and neurotransmitters; the synthesis and catabolism of tyrosine; and the metabolism of microsomes. In nonenzymatic functions it acts as a reducing agent, donating electrons to oxidized molecules and preventing oxidation in order to keep iron and copper atoms in their reduced states. At non-physiological concentrations achieved by intravenous dosing, vitamin C can be a pro-oxidant, with therapeutic toxicity against cancer cells. Vitamin C is a cofactor for the following enzymes:
== Characteristics == Kava was historically grown only in the Pacific islands of Hawaii, Federated States of Micronesia, Vanuatu, Fiji, the Samoas, and Tonga. It appears to have originated in Vanuatu; an inventory of P. methysticum distribution showed it was cultivated on numerous islands of Micronesia, Melanesia, Polynesia, and Hawaii, whereas specimens of P. wichmannii were all from Papua New Guinea, the Solomon Islands, and Vanuatu. Traditionally, plants are harvested around four years of age, as older plants have higher concentrations of kavalactones. After reaching about 2 metres (6.6 ft) in height, plants grow a wider stalk and additional stalks, but not much taller. The roots can reach a depth of 60 centimetres (2.0 ft).
Sources: en.wikipedia.org
It is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, often abbreviated AEDG. The molecule is linear and contains no modified residues, so it is fully described by its sequence.
The compound came out of work on epithalamin, a peptide preparation derived from pineal tissue, conducted largely in Russian laboratories. Later studies in other countries examined it mainly in cell cultures and animal models.
The tetrapeptide sequence is a synthetic construct rather than a described circulating peptide. It was derived by analogy to peptide fractions obtained from tissue extracts, not isolated from blood or tissue as such.
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.