AEDG comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-10-21. 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.
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.
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.
No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.
| 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 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.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
==== MeSH D12.776.220.525.912 – wiskott-aldrich syndrome protein family ==== MeSH D12.776.220.525.912.500 – wiskott-aldrich syndrome protein MeSH D12.776.220.525.912.550 – wiskott-aldrich syndrome protein, neuronal
=== Notable individuals === Some notable individuals have commented publicly on their experiences with LSD. Some of these comments date from the era when it was legally available in the US and Europe for non-medical uses. Others pertain to psychiatric treatment in the 1950s and 1960s. Still others describe experiences with illegal LSD, obtained for philosophic, artistic, therapeutic, spiritual, or recreational purposes.
==== Elemental fractionation between monazite and silicates ==== Elemental fractionation refers to the difference between the amount of an element incorporated into the solid mineral phase and the amount left in the fluid phase. Minerals display preferential intake of certain elements during growth. For example, as monazite grows in size, it preferentially incorporates Th in its crystal structure, resulting in less available Th in the fluid for future monazite growth. Thus, younger monazite tends to have lower Th content. This is one of the principal reasons for the compositional variation of monazite. When considering the whole system of metamorphic rocks, there are other minerals which show elemental fractionation. The interplay between fractionation in monazite and these other minerals has a great impact on the compositional zonation of monazite. The interplay is often caused by the formation and breakdown of the minerals, which is a result of different stages in P-T paths. Dating fractionation-related zonation thus helps put time constraints on metamorphism.
Sources: en.wikipedia.org
Recent genomic and phylogenomic approaches have significantly clarified plastid genome evolution, the horizontal movement of endosymbiont genes to the "host" nuclear genome, and plastid spread throughout the eukaryotic tree of life. It is accepted that both euglenophytes and chlorarachniophytes obtained their chloroplasts from chlorophytes that became endosymbionts. In particular, euglenophyte chloroplasts share the most resemblance with the genus Pyramimonas. However, there is still no clear order in which the secondary and tertiary endosymbioses occurred for the "chromist" lineages (ochrophytes, cryptophytes, haptophytes and myzozoans). Two main models have been proposed to explain the order, both of which agree that cryptophytes obtained their chloroplasts from red algae. One model, hypothesized in 2014 by John W. Stiller and coauthors, suggests that a cryptophyte became the plastid of ochrophytes, which in turn became the plastid of myzozoans and haptophytes. The other model, suggested by Andrzej Bodył and coauthors in 2009, describes that a cryptophyte became the plastid of both haptophytes and ochrophytes, and it is a haptophyte that became the plastid of myzozoans instead. In 2024, a third model by Filip Pietluch and coauthors proposed that there were two independent endosymbioses with red algae: one that originated the cryptophyte plastids (as in the previous models), and subsequently the haptophyte plastids; and another that originated the ochrophyte plastids, where the myzozoans obtained theirs.
== Biosynthesis == The various forms of MSH are generated from different cleavages of the proopiomelanocortin protein, which also yields other important neuropeptides like adrenocorticotropic hormone. Melanocytes in skin make and secrete MSH in response to ultraviolet light, where it increases synthesis of melanin. Some neurons in arcuate nucleus of the hypothalamus make and secrete α-MSH in response to leptin; α-MSH is also made and secreted in the anterior lobe of the pituitary gland.
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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.
Small studies with human participants have been reported, chiefly in Russian-language journals, but they are limited in size and design. No large randomised controlled trial with published results is available.