Telomerase raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-03-14. Anything still debated is marked as such rather than presented as settled.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
Identity and purity are checked by reversed-phase high-performance liquid chromatography, usually with ultraviolet detection near 214 nanometres, where the peptide bond absorbs. Mass spectrometry confirms the expected mass and reveals whether truncation products or adducts are present. Acid hydrolysis followed by amino acid analysis gives the residue ratio, which should approximate one alanine, one glutamate, one aspartate and one glycine. Counter-ions such as acetate or trifluoroacetate remain in the dried product and lower net peptide content, so a stated purity figure on a label does not by itself describe how much peptide a vial holds.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
| Property | Value | Notes |
|---|---|---|
| Storage temperature, solid | Approximately -20 C | Sealed, desiccated, protected from light |
| Typical identity method | Electrospray mass spectrometry | Protonated ion expected near 391 |
| Typical purity method | Reversed-phase HPLC | Ultraviolet detection near 214 nm |
| Common synonyms | Epithalon, epithalone, AEDG | Spelling variants appear in supplier catalogues |
| Solution stability | Days at 2-8 C | Hydrolysis and deamidation limit shelf life |
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
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.
Purity assessment of peptide reagents normally relies on reversed-phase high-performance liquid chromatography. A gradient of acetonitrile in water with trifluoroacetic acid, paired with a C18 stationary phase, separates the target tetrapeptide from truncated sequences and deletion analogues. Detection at 214 nanometres exploits absorbance of the peptide backbone, since the molecule contains no aromatic residue. Results are expressed as a percentage of total peak area. Values above ninety-five percent are typical for research-grade material, although reporting conventions vary between suppliers.
Identity confirmation uses mass spectrometry, usually electrospray ionisation in positive mode or matrix-assisted laser desorption. The protonated free peptide produces a signal near three hundred and ninety-one daltons, while salt adducts shift that value slightly. Tandem mass spectrometry or amino acid analysis supplies sequence-level confirmation, which a single mass measurement cannot. Peptides containing aspartate can cyclise into succinimide intermediates that hydrolyse to isoaspartate isomers of identical mass. Because those isomers are difficult to separate chromatographically, identity and purity results carry more weight when interpreted together.
Storage practice centres on limiting moisture, oxygen, and repeated temperature cycling. Freeze-dried powder is generally held desiccated at minus twenty degrees Celsius or colder and protected from light. Reconstituted solutions are markedly less stable, and the aspartate-glycine junction is prone to succinimide formation at neutral to mildly alkaline pH. Portioning material into single-use aliquots reduces degradation compared with repeated freeze-thaw cycles. Stability data specific to this tetrapeptide remain scarce, so most handling guidance is extrapolated from general peptide chemistry rather than measured directly.
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.
Solubility is high in water, phosphate-buffered saline and normal saline, a pattern that follows from the two acidic residues in the chain. The peptide dissolves poorly in non-polar solvents such as hexane or chloroform. Stock solutions are often prepared in water first and then diluted into the buffer of interest. Because the molecule is small and hydrophilic, filtration through a low-protein-binding membrane is usually straightforward, and visible particulates are uncommon in freshly made solutions.
Identity and purity are established with reversed-phase high-performance liquid chromatography and mass spectrometry. The chromatogram shows the main peak and any truncated or oxidised by-products, while the mass spectrum confirms the expected 390 dalton mass. Amino acid analysis can corroborate composition when a sample's origin is uncertain. Counterion content, particularly residual trifluoroacetate from purification, is frequently reported alongside purity because it shifts the net mass of the solid.
== Barotrauma in other animals == Whales and dolphins develop severely disabling barotrauma when exposed to excessive pressure changes induced by navy sonar, oil industry airguns, explosives, undersea earthquakes and volcanic eruptions. Injury and mortality of fish, marine mammals, including sea otters, seals, dolphins and whales, and birds by underwater explosions has been recorded in several studies. It has been claimed that bats can suffer fatal barotrauma in the low pressure zones behind the blades of wind turbines due to their more fragile mammalian lung structure in comparison with the more robust avian lungs, which are less affected by pressure change. The claims that have been made that bats can be killed by lung barotrauma when flying in low-pressure regions close to operating wind-turbine blades, have been supported by reports of measurements of the pressures around the turbine blades. The diagnosis and contribution of barotrauma to bat deaths near wind turbine blades have been disputed by other research comparing dead bats found near wind turbines with bats killed by impact with buildings in areas with no turbines.
=== Centimorgan: Genetic linkage === In genetics, a centimorgan (abbreviated cM) or map unit (m.u.) is a unit for measuring genetic linkage. It is defined as the distance between chromosome positions (also termed loci or markers) for which the expected average number of intervening chromosomal crossovers in a single generation is 0.01. It is often used to infer distance along a chromosome. One centimorgan corresponds to about 1 million base pairs in humans on average.
=== Sociological === Anorexia nervosa has been increasingly diagnosed since 1950; the increase has been linked to vulnerability and internalization of body ideals. People in professions where there is a particular social pressure to be thin (such as models and dancers) were more likely to develop anorexia, and those with anorexia have much higher contact with cultural sources that promote weight loss. Internet usage heavily leads to deep societal practices of the upkeep of slender body types. Thus leading many to have symptoms of body dissatisfaction and low body image satisfaction. This trend can also be observed for people who partake in certain sports, such as jockeys and wrestlers. There is a higher incidence and prevalence of anorexia nervosa in sports with an emphasis on aesthetics, where low body fat is advantageous, and sports in which one has to make weight for competition. Family group dynamics can play a role in the perpetuation of anorexia including negative expressed emotion in overprotective families where blame is frequently experienced among its members. In the face of constant pressure to be thin, often perpetuated by teasing and bullying, feelings of low self-esteem and self-worth can arise, including the perception that one is not "deserving" of food.
== Hospitals == People's Hospital of Ningxia Hospital of Traditional Chinese Medicine of Ningxia Ningxia Medical College Affiliated Hospital Yinchuan Hospital of Traditional Chinese Medicine Yinchuan People's Hospital Yinchuan Stomatological Hospital Yinchuan Women and Children's Healthcare Center Women and Children's Healthcare Center of Ningixa Yinchuan No.1 People's Hospital Yinchuan No.2 People's Hospital Yinchuan No.3 People's Hospital Shizuishan No.2 People's Hospital Guyuan Hospital of Ningxia
Kenneth D. Tew is a Scottish-American pharmacologist, academic and author. He is a professor in the Department of Cell & Molecular Pharmacology and the John C. West Endowed Chair in Cancer Research at the Medical University of South Carolina. Tew's research primarily focuses on identifying cancer strategies with strong translational potential, particularly in the context of redox pathways, and resistance to various drugs to understand redox mechanisms and their connections to essential signaling pathways. He has authored, co-authored and edited research articles and books such as Preclinical and Clinical Modulation of Anticancer Drugs and Basic Science of Cancer. He is the recipient of the Outstanding Investigator Grant from the National Cancer Institute in 1993, the 2003 American Cancer Society Scientific Research Award and the 2010 Astellas USA Foundation Award from the American Society for Pharmacology and Experimental Therapeutics. Tew is an Elected Fellow of the American Association for the Advancement of Science and the American Society for Pharmacology and Experimental Therapeutics. He is an Executive Editor of Biomedicine & Pharmacotherapy.
Sources: en.wikipedia.org
=== Membrane proteins === Multi-monoubiquitylation can mark transmembrane proteins (for example, receptors) for removal from membranes (internalisation) and fulfil several signalling roles within the cell. When cell-surface transmembrane molecules are tagged with ubiquitin, the subcellular localization of the protein is altered, often targeting the protein for destruction in lysosomes. This serves as a negative feedback mechanism, because often the stimulation of receptors by ligands increases their rate of ubiquitylation and internalisation. Like monoubiquitylation, lysine 63-linked polyubiquitin chains also has a role in the trafficking some membrane proteins.
Joullié (born 1927), Brazilian, American organic chemist Isabella Karle (1921–2017), American crystallographer Joyce Jacobson Kaufman (1929–2016), American chemist, Pharmacologist Judith Klinman (born 1941), American biochemist Teresa Kowalska (1946-2023), Polish chemist, co-founder of Acta Chromatographia Marisa Kozlowski, American organic chemist Stephanie Kwolek (1923–2014), American chemist, inventor of Kevlar Sine Larsen (1943–2025), Danish structural chemist and crystallographer Kathleen Lonsdale (1903–1971), British crystallographer Yvonne Connolly Martin (born 1936), American physical biochemist working on cheminformatics and computer-aided drug design in the US Marie Marynard Daly (1921–2001), First African American woman to earn her PhD in the United States Cynthia A.
=== Identification of protein localization across cells === For medication development, the identification of therapeutic targets, and biological research, it is essential to comprehend where proteins are located within a cell. The subcellular locations of proteins inside the cell and their functions are closely related. The relationship between protein function and localization suggests that when proteins move, their functions may change or acquire new characteristics. A protein's subcellular placement can be determined using a variety of methods. Numerous efficient and reliable computational tools and strategies have been created and used to identify protein subcellular localization. With the aid of subcellular fractionation methods, WB continues to be an important fundamental method for the investigation and comprehension of protein localization.
=== Limitations of non-invasive electrical and magnetic methods === Brain tissue stimulation using non-invasive electrical and magnetic methods raises several concerns, including the following: The first issue is the uncertain dose for healthy stimulation. While neurophysiology lacks knowledge about the nature of such a treatment of nervous diseases at the cellular level, non-invasive electrical and magnetic therapies involve excessive exposure of the brain to an intense field, which is several times and even orders of magnitude higher than natural electromagnetic fields in the brain. Another significant challenge of non-invasive electrical and magnetic methods is to localize the effect of stimulation on specific neuronal networks that need to be treated. We still need to gain knowledge about mental processes at the cellular level. Neuronal correlates of cognitive functions are still intriguing questions for contemporary research. Non-invasive electrical and magnetic brain tissue stimulation targets a large area of poorly characterized tissue. Therefore, it is unclear whether electrical and magnetic fields reach only the neuronal networks of the brain that need treatment. Again, these methods involve excessive exposure to intense electrical and magnetic fields several times and even orders of magnitude higher than natural ones in the brain. However, non-invasive electrical and magnetic brain tissue methods cannot target only the neuronal networks that need to be treated. The undefined radiation target can destroy healthy cells during therapy.
== History == Phenylpiracetam was first described in the scientific literature by 1983. It was developed in 1983 as a medication for Soviet cosmonauts to treat the prolonged stresses of working in space. Phenylpiracetam was created at the Russian Academy of Sciences Institute of Biomedical Problems in an effort led by psychopharmacologist Valentina Ivanovna Akhapkina (Валентина Ивановна Ахапкина). Subsequently, it became available as a prescription drug in Russia. It was approved in 2003 for treatment of various conditions. Pilot-cosmonaut Aleksandr Serebrov described being issued and using phenylpiracetam, as well as it being included in the Soyuz spacecraft's standard emergency medical kit, during his 197-days working in space aboard the Mir space station. He reported "the drug acts as the equalizer of the whole organism, "tidying it up", completely excluding impulsiveness and irritability inevitable in the stressful conditions of space flight."
Sources: en.wikipedia.org
=== Cluster headaches, migraine, and hypnic headache === Studies testing prophylactic use of lithium in cluster headaches (when compared to verapamil), migraine attacks, and hypnic headache indicate good efficacy.
Macimorelin (INN) – or Macrilen (trade name) – is a drug that was developed by Aeterna Zentaris for use in the diagnosis of adult growth hormone deficiency. Macimorelin acetate, the salt formulation, is a synthetic growth hormone secretagogue receptor agonist. It is a growth hormone secretagogue receptor (ghrelin receptor) agonist, causing release of growth hormone from the pituitary gland. Macimorelin acetate is described chemically as D-Tryptophanamide, 2-methylalanyl-N-[(1R)-1-(formylamino)-2-(1H-indol-3-yl)ethyl]-acetate. Macimorelin (Macrilen) was invented and first synthesized at University of Montpellier, Centre National de la Recherche Scientitifique (CNRS), France. This transpired from a long-lasting research collaboration with Aeterna Zentaris. Aeterna Zentaris later in-licensed macimorelin as a development candidate from the CNRS and proceeded with the pre-clinical and clinical development of the compound. As of January 2014, it was in Phase III clinical trials. The phase III trial for growth hormone deficiency is expected to be complete in December 2016. As of December 2017, it was FDA-approved as a method to diagnose growth hormone deficiency. Traditionally, growth hormone deficiency was diagnosed via means of insulin tolerance test (IST) or glucagon stimulation test (GST). These two means are done parenterally, whereas Macrilen boasts an oral formulation for ease of administration for patients and providers. In November 2018 Novo Nordisk would acquire the rights to Macrilen, at a cost of $145 million.
isochromosome A type of abnormal chromosome in which the arms of the chromosome are mirror images of each other. Isochromosome formation is equivalent to simultaneous duplication and deletion events such that two copies of either the long arm or the short arm comprise the resulting chromosome.
Philip wrote a contract giving Tessa half of all the rights to the novel, which stated that Tessa "participated to a great extent in writing the outline and novel A Scanner Darkly with me, and I owe her one half of all income derived from it". There was also the challenge of transmuting the events into "science fiction", as Dick felt that he could not sell a mainstream or literary novel after several previous failures. Providing invaluable aid in this field was Judy-Lynn del Rey, head of Ballantine Books' SF division, which had optioned the book. Del Rey suggested the timeline change to 1994 and emphasized the more futuristic elements of the novel, such as the "scramble suit" employed by Fred (which, incidentally, emerged from one of the mystical experiences). Yet much of the dialogue spoken by the characters used hippie slang, dating the events of the novel to their "true" time-frame of 1970–72. Upon its publication in 1977, A Scanner Darkly was hailed by ALA Booklist as "his best yet!" Brian Aldiss lauded it as "the best book of the year", while Robert Silverberg praised the novel as "a masterpiece of sorts, full of demonic intensity", but concluded that "it happens also not to be a very successful novel... a failure, but a stunning failure". Spider Robinson panned the novel as "sometimes fascinating, sometimes hilarious, [but] usually deadly boring". Sales were typical for the SF genre in America, but hardcover editions were issued in Europe, where all of Dick's works were warmly received.
Sources: en.wikipedia.org
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.
Reversed-phase chromatography with ultraviolet detection gives a purity percentage, while mass spectrometry confirms identity. Amino acid analysis checks the residue composition. Buyers typically request a certificate of analysis showing these measurements for the specific lot.
It is not authorised as a medicine in the United States or the European Union. Material is sold there as a research chemical or cosmetic ingredient. Some related short peptides are registered drugs in Russia, which is a distinct national situation rather than a general approval.
Vladimir Khavinson and colleagues at research institutes in Saint Petersburg developed and studied the peptide. Their program examined short peptides as regulators of aging and neuroendocrine function. Epitalon was one of several compounds produced by that group.