This is a working overview of Epithalamin, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-01-12. Anything still debated is marked as such rather than presented as settled.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
The published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
Reversed-phase high-performance liquid chromatography is the standard approach for assessing purity, usually with ultraviolet detection near 214 nm, where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the molecular mass and helps reveal truncation or deletion byproducts. Amino acid analysis can verify composition, and counterion content is sometimes measured because peptides purified with trifluoroacetic acid retain variable amounts of that salt. Purity figures reported without a stated method and detection wavelength are difficult to interpret.
Material sold for research use varies widely in documented quality. A useful verification package includes a certificate of analysis that states peptide content rather than only net weight, the chromatographic method and column used, and a mass spectrum consistent with the expected mass. Independent testing by a third-party laboratory is occasionally reported. Statements of identity resting only on a supplier label provide little assurance, and the gap between nominal mass and actual peptide content can be substantial once counterions and residual water are counted.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Synthetic tetrapeptide, four residues |
| Nominal mass | Approximately 390 Da | Free peptide; salt forms differ |
| Appearance | White to off-white powder | Commonly supplied lyophilised |
| Solubility class | Freely soluble in water | Also dissolves in aqueous buffer |
| Typical storage | −20 °C, desiccated | Cold packs used during transport |
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.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. It was designed at the St. Petersburg Institute of Bioregulation and Gerontology as a short, chemically defined analogue of epithalamin, a fraction obtained from bovine pineal tissue. Small peptide bioregulators of this type formed a long-running line of work there from the 1980s onward. Because the molecule is produced by solid-phase synthesis rather than extraction, its composition is exact and its purity can be measured directly.
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.
Verification of research-grade material involves comparing a supplier chromatogram against an in-house reference, checking the observed mass against the calculated value, and where possible confirming residue order by tandem mass spectrometry or enzymatic peptide mapping. Purity claims should be read alongside the method used to obtain them, because detection wavelength and integration settings alter the result. Batch-specific data, rather than a generic grade statement, is the informative part of a certificate.
Identity and purity of epitalon samples are normally established by reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, combined with mass spectrometry. The mass spectrum confirms the expected molecular ion and can reveal truncated or oxidised by-products. Amino acid analysis after acid hydrolysis verifies that the four residues are present in the expected ratio. Certificates typically report a purity figure taken from chromatographic peak area, expressed as a percentage of total integrated signal.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
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.
== Classification == As a definition of "cell type" is yet to be agreed, it is not possible yet to arrive at a precise number of human cell types. There is, for example, significant variation in these cell types depending on the specific surface proteins they possess. An extensive listing of human cell types was published by Vickaryous and Hall in 2006, collecting 411 different types of human cells, including 145 types of neurons. The Human Cell Atlas project, which started in 2016, had as one of its goals to "catalog all cell types (for example, immune cells or brain cells) and sub-types in the human body". By 2018, the Human Cell Atlas description based the project on the assumption that "our characterization of the hundreds of types and subtypes of cells in the human body is limited", but the word hundreds was removed in later versions. On 2021, Stephen Quake guessed that the upper limit of the number of human cell types would be around 6000, based on a reasoning that "if biologists had discovered only 5% of cell types in the human body, then the upper limit of cell types to discover is somewhere around 6000 (i.e., 300/0.05)." Other different efforts have used different numbers. A count of cells in the human body published in 2023 divided the cells in about 400 types to perform the calculation.
Sarcosine is an intermediate and byproduct in glycine synthesis and degradation. Sarcosine is metabolized to glycine by the enzyme sarcosine dehydrogenase, while glycine-N-methyltransferase generates sarcosine from glycine. Sarcosine is an amino acid derivative that is naturally found in muscles and other body tissues. In the laboratory, it may be synthesized from chloroacetic acid and methylamine. Sarcosine is an intermediate in the metabolism of choline to glycine. Sarcosine, like the related compounds dimethylglycine (DMG) and trimethylglycine (betaine, TMG), is formed via the metabolism of nutrients such as choline and methionine, which both contain methyl groups used in a wide range of biochemical reactions. Sarcosine is rapidly degraded to glycine, which, in addition to its importance as a constituent of protein, plays a significant role in various physiological processes as a prime metabolic source of components of living cells such as glutathione, creatine, purines and serine. The concentration of sarcosine in blood serum of normal human subjects is 1.4 ± 0.6 micromolar.
=== 19th century === Apparently unaware of Smeaton's work, the same principle was identified by Frenchman Louis Vicat in the first decade of the nineteenth century. Vicat went on to devise a method of combining chalk and clay into an intimate mixture, and, burning this, produced an "artificial cement" in 1817 considered the "principal forerunner" of Portland cement and "...Edgar Dobbs of Southwark patented a cement of this kind in 1811." In Russia, Egor Cheliev created a new binder by mixing lime and clay. His results were published in 1822 in his book A Treatise on the Art to Prepare a Good Mortar published in St. Petersburg. A few years later in 1825, he published another book, which described various methods of making cement and concrete, and the benefits of cement in the construction of buildings and embankments.
== Clinical significance == MetO increases with age in body tissues, which is believed by some to contribute to biological ageing. Moreover, levels of methionine sulfoxide reductase A (MsrA) decline in aging tissues in mice and in association with age-related disease in humans. There is thus a rationale for thinking that by maintaining the structureincreased levels or activity of MsrA might retard the rate of aging. Indeed, transgenic Drosophila (fruit flies) that overexpress methionine sulfoxide reductase show extended lifespan. However, the effects of MsrA overexpression in mice were ambiguous. MsrA is found in both the cytosol and the energy-producing mitochondria, where most of the body's endogenous free radicals are produced. Transgenically increasing the levels of MsrA in either the cytosol or the mitochondria had no significant effect on lifespan assessed by most standard statistical tests, and may possibly have led to early deaths in the cytosol-specific mice, although the survival curves appeared to suggest a slight increase in maximum (90%) survivorship, as did analysis using Boschloo's test, a binomial test designed to test greater extreme variation. Deletion of this gene has been associated with insulin resistance in mice, while overexpression reduces insulin resistance in old mice.
Sources: en.wikipedia.org
Dietary supplement companies aggressively promote NMN products claiming these benefits. NMN is a precursor to NAD+ biosynthesis, and dietary NMN supplementation has been shown to increase NAD+ concentrations and thus has the potential to mitigate aging-related disorders such as oxidative stress, DNA damage, neurodegeneration, and inflammatory responses. The potential benefits and risks of NMN supplementation as of 2023 are currently under study. Life extension Anti-aging movement
This version underwent another three weeks of testing to become the final release code; the game was still unfinished when Activision forced its release. Bloodlines' creative director Jason Anderson blamed Activision, saying that the publisher took the game from Troika without providing enough time to test and polish it. Conversely, Boyarsky defended Activision for supporting Troika as the project exceeded its budget and schedule. During the nearly four years of development, Anderson estimated that the team worked overtime for all but two months.
== Function == Through the diverse outputs of the orexin system, the orexin neurons in the lateral hypothalamus mediate an array of functions. Two of the most commonly noted functions of orexin peptides in the lateral hypothalamus are the promotion of feeding behavior and arousal (i.e., wakefulness). More generally, the orexinergic neural projections of the lateral hypothalamus are involved in thermoregulation, regulating gastrointestinal motility and gastrointestinal function by way of the dorsal nucleus of the vagus nerve, reducing pain and nociception through several output structures (e.g., periaqueductal gray matter), modulating the rewarding property of stimuli through the ventral tegmental area projections and other outputs in the reward system, regulating energy homeostasis and neuroendocrine functions (e.g., HPA axis, HPG axis, and HPT axis) through other hypothalamic outputs, and regulating visceral functions (e.g., respiration, blood pressure, and urination) via a group of structures in the brain stem, among other functions. The endocannabinoid system and the orexin system mediate many of the same cognitive and physical effects, and a significant overlap in their function and localization has been noted in a 2013 medical review; the CB1–OX1 receptor heterodimer produces a 100-fold amplification of the potency of the orexin receptor 1-mediated ERK pathway signaling. Unique functional interactions have been noted as well, such as an OX1-induced CB1 pressor response in the rostral ventrolateral medulla.
== See also == Alpha toxin Pathology Lysosomal acid lipase deficiency Peripheral membrane proteins Phospholipase A Phospholipase C Triglyceride lipase Phospholipase A2 Outer membrane phospholipase A1 Patatin-like phospholipase
Mycoplasma pneumoniae Chlamydia pneumoniae Hepatitis B virus (HBV) Parvovirus B19 Adenovirus (ADV) Respiratory syncytial virus (RSV) The immune cell involvement in polymyalgia rheumatica includes the activation of dendritic cells and monocytes/macrophages, leading to inflammation in the synovium and bursae of the shoulder and hip girdles which is primarily mediated by the innate immune system. There is an altered balance between Th17 and Treg cells, with increased IL-6 levels driving Th17 cell activation. Disturbed B cell distribution and function are also observed, with a decrease in circulating B cells that recover after steroid treatment. Additionally, systemic activation of circulating monocytes is associated with increased IL-6 and IL-1 beta production. Associations of uncertain significance with multiple types of TNF have also been found. Despite the severe pain associated with the condition in multiple muscle groups, as well as the signs of systemic inflammation, muscle biopsies have found no signs of localized inflammation in muscle tissue in patients with PMR. Electromyography studies also typically turn up normal. The only locations known definitively to be inflamed in PMR are the synovial membranes and bursae of joints. Persons having the HLA-DR4 type of human leucocyte antigen appear to have a higher risk of PMR.
Sources: en.wikipedia.org
No. Epithalamin is a heterogeneous peptide fraction obtained from pineal gland extract and contains many components. Epitalon is a single synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly. Researchers synthesised the shorter peptide while attempting to identify active sequences within the extract.
No endogenous peptide with this exact sequence has been described as a circulating hormone or signalling molecule. The tetrapeptide was designed as a synthetic analogue based on fragments observed in pineal preparations. Any activity discussed in the literature therefore refers to administered material rather than to a natural pool of the compound.
It is not an approved medicine in major jurisdictions and does not appear in the major pharmacopoeias. Material is usually distributed as a research chemical or laboratory reagent. Such labelling places handling responsibility on the purchaser and does not indicate that a regulatory body has reviewed the substance.
The powder is normally kept at −20 °C or below in a sealed, moisture-protected container. Letting the vial reach room temperature before opening helps prevent condensation on the contents.