The short version of telomerase fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-02. Anything still debated is marked as such rather than presented as settled.
（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, 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.
| 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 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.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
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.
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an organ's blood flow. Each organ will have its own specific clearance conditions, which will relate to its mode of action. The «renal clearance» rate will be determined by factors such as the degree of plasma protein binding as the drug will only be filtered out if it is in the unbound free form, the degree of saturation of the transporters (active secretion depends on transporter proteins that can become saturated) or the number of functioning nephrons (hence the importance of factors such as kidney failure). As «hepatic clearance» is an active process it is therefore determined by factors that alter an organism's metabolism such as the number of functioning hepatocytes, this is the reason that liver failure has such clinical importance.
=== November === 14 November AI-generated poetry is shown to be indistinguishable from human-written poetry and is rated more favourably. A study in the British Journal of Sports Medicine finds that over-40s could live an extra five years if they adopted the exercise routines of the top 25% of the population, while the least physically active could potentially add 11 years to their lifespan. The first direct image of what the shape of a photon would look like is created. 15 November – Measles cases are reported to have surged across the world, with an estimated 10.3 million infections in 2023, a 20% increase from 2022. 18 November – Coal ash from power plants across the United States is likely to contain up to 11 million tons of rare-earth elements – nearly eight times the amount the US has in domestic reserves – according to a study by the University of Texas at Austin. 19 November Northern and central parts of the Great Barrier Reef are reported to have suffered their worst coral bleaching on record, with up to 72 per cent mortality. Starship flight test 6 is launched. 20 November Climate change is found to have increased Atlantic hurricane wind speeds by 18 mph (29 km/h). Progress on the Human Cell Atlas is reported, with a collection of 40 new scientific papers in Nature describing the project's latest discoveries. 21 November – The first close-up image of a star outside the Milky Way is reported, using the European Southern Observatory's Very Large Telescope Interferometer.
Sources: en.wikipedia.org
== Pathology == When the sulcular depth is chronically in excess of three millimeters, regular home care may be insufficient to properly cleanse the full depth of the sulcus, allowing food debris and microbes to accumulate, forming dental biofilm. This poses a danger to the periodontal ligament (PDL) fibers that attach the gingiva to the tooth. If accumulated microbes remain undisturbed in a sulcus for an extended period of time, they will penetrate and ultimately destroy the delicate soft tissue and periodontal attachment fibers. If left untreated, this process may lead to a deepening of the sulcus, recession, destruction of the periodontium, including the bony tooth socket, tooth mobility, and tooth loss. A periodontal pocket is a dental term indicating the presence of an abnormally deepened gingival sulcus.
International Water Association Professional / research organization NSF International – Independent non-profit standards organization WHO.int, WHO Guidelines Safe and Sustainable Water for Haiti web site hosted by Grand Valley State University Different types of water purification systems compared
== Genetics == The gene encoding the enzyme is referred to as DDC is located on chromosome 7 in humans. It consists of 15 exons encoding a protein of 480 amino acids. Single nucleotide polymorphisms and other gene variations have been investigated in relation to neuropsychiatric disorders, for example, a one-base pair deletion at 601 and a four-base pair deletion at 722–725 in exon 1 in relation to bipolar disorder and autism. No direct correlation between gene variation and autism was found. More than 50 mutations of DDC have been correlated with AADC deficiency. This condition is most prevalent in Asia, presumably due to the founder effect. Alternative splicing events and promoters have been observed that lead to various forms of the AADC enzyme. Unique usage of certain promoters leads to transcription of only the first exon to produce an extra-neuronal isoform, and splicing of exon 3 leads to a product devoid of enzymatic activity. Analyses via porcine specimens have elucidated two AADC isoforms – resulting from exclusion of exon 5 and exons 5 and 6 – that lack a portion of the decarboxylating domain.
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.
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.