The short version of counterion fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-08. Anything still debated is marked as such rather than presented as settled.
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.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
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.
Lyophilised epitalon is generally held at minus twenty degrees Celsius in a sealed container kept dry and dark. Cooler conditions are sometimes recommended for long-term archives. The solid takes up moisture readily enough that repeated opening of a vial introduces water, so dividing a batch into smaller portions before storage lowers degradation risk. Aqueous solutions are less durable than the dry powder and are usually prepared shortly before use, then kept cold and shielded from light to slow hydrolysis and oxidation.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four amino acid residues |
| Residue sequence | Ala-Glu-Asp-Gly | Abbreviated AEDG |
| Approximate mass | 390.35 Da | Monoisotopic, free base form |
| Parent preparation | Epithalamin extract | Derived from pineal tissue |
| Common spelling variants | Epithalon, epithalone, AEDG | Affects literature retrieval |
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.
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.
Peptides of this size are generally stable as dry solids but degrade in solution over time. The principal routes are hydrolysis of the peptide backbone and oxidation, with hydrolysis favoured by elevated temperature and extreme pH. Aqueous solutions held at room temperature can show measurable loss of purity within days, while frozen aliquots are considerably more durable. Because the sequence contains neither cysteine nor methionine, oxidation is less of a concern than for many other peptides, but pH control during handling still matters.
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.
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.
=== Reducing risk of cancer === According to the American Cancer Society, "There is growing evidence that eating traditional soy foods such as tofu may lower the risk of cancers of the breast, prostate, or endometrium (lining of the uterus), and there is some evidence it may lower the risk of certain other cancers." There is insufficient research to indicate whether taking soy dietary supplements (e.g., as a pill or capsule) has any effect on health or cancer risk. As of 2018, rigorous dietary clinical research in people with cancer has proved inconclusive.
autoignition temperature Also kindling point. The lowest temperature at which a given substance will spontaneously ignite in a normal atmosphere without an external source of ignition such as a flame or spark, i.e. when the ambient temperature is sufficiently high to provide the activation energy needed for combustion. Substances which spontaneously ignite at naturally occurring temperatures are termed pyrophoric. Compare ignition temperature.
=== Structure of Green EosFP === In its anionic form, the green chromophore has an absorption maxima at 506 nm and an emission maxima at 516 nm. It is formed autocatalytically from amino acids His-62, Tyr-63 and Gly-64. Immediately surrounding the chromophore there is a cluster of charged or polar amino acids as well as structural water molecules. Above the plane of the chromophore, there is a network of hydrogen bond interactions between Glu-144, His-194, Glu-212 and Gln-38. Arg-66 and Arg-91 participate in hydrogen bonding with the carbonyl oxygen of green Eos's imidazolinone moiety. The His-62 side chain lies in an unpolar environment. Conversion from the green to red form depends on the presence of a histidine in the first position of the tripeptide HYG that forms the chromophore. When this histidine residue is substituted with M, S, T or L, Eos only emits bright green light and no longer acts as a photoconvertible fluorescent protein.
The response factor, F, is equal to the ratios of the k's, which are constant. Therefore, F is constant. What this means is that regardless of the amounts of octane and nonane in solution, the ratio of the ratios of area to concentration will always yield a constant. In practice, a solution containing known amounts of both octane and nonane is injected into a GC and a response factor, F, is calculated. Then a separate solution with an unknown amount of octane and a known amount of nonane is injected. The response factor is applied to the data from the second solution and the unknown concentration of the octane is found.
Sources: en.wikipedia.org
== Contraindications == Labetalol is contraindicated in people with overt cardiac failure, greater-than-first-degree heart block, severe bradycardia, cardiogenic shock, severe hypotension, anyone with a history of obstructive airway disease including asthma, and those with hypersensitivity to the drug.
DHX8 protein has its main focuses of expression in the brain, especially in the cerebellum where it can be found mostly in Purkinje cells. Other important are the prostate and the gallbladder, which are zones where the polypetide is found also highly expressed. DHX8 protein is not expressed in all tissues and organs significantly, some clear examples are the bone marrow or the soft tissue (Peripheral nerve), where we do not have enough quantity of the protein to be representative.
In cellular biology, the Wnt signaling pathways are a group of signal transduction pathways which begin with proteins that pass signals into a cell through cell surface receptors. The name Wnt, pronounced "wint", is a portmanteau created from the names Wingless and Int-1. Wnt signaling pathways use either nearby cell-cell communication (paracrine) or same-cell communication (autocrine). They are highly evolutionarily conserved in animals, which means they are similar across animal species from fruit flies to humans. Three Wnt signaling pathways have been characterized: the canonical Wnt pathway, the noncanonical planar cell polarity pathway, and the noncanonical Wnt/calcium pathway. All three pathways are activated by the binding of a Wnt-protein ligand to a Frizzled family receptor, which passes the biological signal to the Dishevelled protein inside the cell. The canonical Wnt pathway leads to regulation of gene transcription, and is thought to be negatively regulated in part by the SPATS1 gene. The noncanonical planar cell polarity pathway regulates the cytoskeleton that is responsible for the shape of the cell. The noncanonical Wnt/calcium pathway regulates calcium inside the cell. Wnt signaling was first identified for its role in carcinogenesis, then for its function in embryonic development. The embryonic processes it controls include body axis patterning, cell fate specification, cell proliferation and cell migration. These processes are necessary for proper formation of important tissues including bone, heart and muscle.
== History == MusclePharm Corporation was incorporated on August 4, 2006. On February 18, 2010, the company acquired Muscle Pharm, LLC, and as a result, MusclePharm then became a wholly owned subsidiary. In 2021, MusclePharm named Sabina Rizvi its first president and CFO. In 2023, MusclePharm named Eric Hillman CEO.
==== Commercialization ==== The company announced in November 2021 that it aims to achieve mass-manufacturing in 2024 of its silicon batteries, having pouch-cell samples produced by its manufacturing partner EVE Energy sent to be tested by global car makers. The company announced in 2023 that its batteries will be commercially available in VinFast vehicles in 2025. The CEO said that the company does not plan to become a battery manufacturer or supplier, but instead plans to license its technology to major manufacturers or lease dedicated manufacturing capacity from existing suppliers, saying its silicon batteries can be manufactured using existing factories and manufacturing processes. StoreDot demonstrated its batteries in a prototype Polestar 5 sedan in 2024, however the 2025 model was not set to debut with StoreDot batteries but with batteries developed and manufactured by SK On. StoreDot batteries were still in the testing phase in October 2024 and they had not been incorporated into any upcoming vehicle platforms. StoreDot stated in 2026 it needs two more years of development in order to commercialize its product.
Sources: en.wikipedia.org
== History == Relief Therapeutics was founded in 2013 by Gael Hédou with the aim of developing new treatments for diseases with high unmet needs. The company today considers itself the successor to Mondobiotech, which was founded in 2000 by Fabio Cavalli and Dorian Bevec. Mondobiotech began research into Vasoactive intestinal peptide (VIP), a naturally occurring substance in humans that was first identified in the 1970s. They were granted US and European patents for a synthetic version of VIP known as aviptadil in 2006. On June 23, 2013, Mondobiotech merged with Italian pharmaceutical company Pierrel Research International to form a new Contract research organization known as Therametrics. On July 14, 2016, Therametrics merged with Relief Therapeutics to form Relief Therapeutics Holdings AG, which inherited all patents related to aviptadil.
Not far from Via Po stands the symbol of Turin, namely the Mole Antonelliana, so named after the architect who built it, Alessandro Antonelli. Construction began in 1863 as a Jewish synagogue. Nowadays it houses the National Museum of Cinema and it is believed to be the tallest museum in the world at 167 m (548 ft). The building is depicted on the Italian 2-cent coin.
== Ethnic/cultural affinity groups == Afro-American Association American Australian Association, a privately-funded nonprofit organization based in New York Amhara Association of America Australian American Association, a community organization based in Australia
After the Boer War, the British army underwent reform focused on lessening the emphasis placed on mounted units. It was determined that the traditional role of cavalry was antiquated and improperly used on the battlefield in the Boer War, and the First World War was the proof that mounted attacks had no place in twentieth century combat. Cavalry was put to better use after the reforms in the theatres of the Middle East and World War I, and the idea of mounted infantry was useful in times when war was more mobile. An example was during the First World War during the Battle of Mons, in which the British cavalry held the Belgian town against German assault.
Sources: Monocytes; Dendritic cells; Primary T cells; Mast cells; Granulocytes; Macrophages; Adipocytes; Endothelial cells Most complement systems are synthesized by hepatocytes in the liver, however, properdin is synthesized by neutrophils, monocytes, and T cells. Properdin is a positive regulator of the alternative pathway through its mechanism of stabilizing the C3 convertase (C3bBb). Primary T cells, monocytes, macrophages, dendritic cells, granulocytes, and mast cells synthesize mRNA to secrete properdin. Functional properdin is a product of human liver-derived HEP G2 cells. Properdin localized in the granules of neutrophils are released by TNF, TNF/fMLP, PMA, C5a, or IL-8. Additionally, neutrophils promote complement activation upon binding of cytokines, which stabilizes the alternative pathway via release of properdin, increasing defense against microorganisms. Properdin sourced from T cells promote phagocytosis of apoptotic T cells, which is an indication of their function in recognizing and clearing out apoptotic cells. Properdin is also sourced in endothelial cells along with the other complement proteins. Endothelial gene transcripts are induced when shear stress occurs, followed by properdin release into extracellular compartments. Properdin plays an important role in tissue regulation, energy metabolism, and lipid metabolism. An experiment in properdin deficient mice concluded that properdin deficiency results in fat storage and less energy output in comparison to wild-type mice. Properdin regulates fatty acid uptake into adipose tissue.
Sources: en.wikipedia.org
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.
No. Epithalamin is a heterogeneous extract containing many peptides, while epitalon is a single synthesised tetrapeptide. Publications sometimes treat findings from the two as equivalent, which is a common source of confusion. Their compositions differ and they are not interchangeable in analytical terms.
Most published work uses cell cultures or rodents because those models are faster and less costly to run. The few human trials that have been reported are small, and several lack control groups or blinding. This restricts what can reasonably be concluded about effects in people.
The usual approach is reversed-phase HPLC with ultraviolet detection, reported as a percentage of total peak area. Mass spectrometry is used alongside chromatography to confirm identity rather than purity alone.