A practical reference on telomerase: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-02-01. Anything still debated is marked as such rather than presented as settled.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
Laboratory-grade epitalon is typically supplied as a lyophilized powder. Purity is commonly assessed with reverse-phase high-performance liquid chromatography, often paired with mass spectrometry to confirm molecular identity. Amino acid analysis and peptide mapping can provide additional confirmation of sequence. Certificates of analysis for research materials frequently report purity above 95 percent, although the methods behind such figures vary between suppliers. The absence of a pharmacopeial monograph means that no single standardized assay defines the compound, so reported results depend on the analytical protocol chosen.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Free acid form of the tetrapeptide |
| Molecular mass | About 390.35 Da | Calculated monoisotopic value |
| Appearance | White to off-white powder | Typical lyophilized presentation |
| Solubility | Soluble in water | Also dissolves in buffered saline |
| Storage temperature | Minus 20 degrees Celsius | Dry, dark conditions; avoid repeated thawing |
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.
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.
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
Platelet-rich plasma is increasingly used to enhance healing in dental and oral surgery, particularly for aging patients. PRP is derived from the patient's blood through centrifugation, concentrating growth factors that are crucial for wound healing and tissue repair.
=== Journey to Europe === For a few centuries, Europeans had experimented with American vines and plants in their soil. Many varieties were imported from America without regulation, disregarding the possibility of pest transfer and related problems. Jules-Emile Planchon, a French biologist who identified the Phylloxera in the 1860s, maintained that the transfer of American vines and plants into Europe greatly increased between roughly 1858 and 1862, and accidentally introduced Phylloxera to Europe around 1860. Others say that the aphid did not enter France until around 1863. The advent of steamships may have been a factor: as they were faster than sailing ships, the Phylloxera were better able to survive the shorter ocean voyage.
10 May Transgender woman Lexi-Rose Crawford is sentenced to 9 years in prison for raping a female victim, with the sentence to be served in a men's prison. The government confirms it will replace its plan for all EU-era legislation to expire at the end of 2023 with a list of 600 laws it wishes to replace. Vodafone confirms it will begin switching off its 3G network from June, prompting concerns that people with older and more basic phones could experience "digital poverty". The legal case Duke of Sussex v Mirror Group Newspapers begins at the High Court. Adam Price announces his resignation as leader of Plaid Cymru after a report found a culture of misogyny, harassment and bullying in the party. 11 May Wind power is reported as the main source of electricity generation in the UK for the first three months of the year, overtaking gas. The government announces that TransPennine Express will be stripped of its contract and nationalised, due to poor service and cancelled trains. The Bank of England raises its baseline interest rate for the 12th consecutive time, from 4.25% to 4.5%, increasing mortgage and loan costs, but increasing savings income for many. Defence Secretary Ben Wallace confirms that the UK will supply Storm Shadow cruise missiles to Ukraine, to assist the country in repelling the Russian invasion. These have a much longer range (250 km/155 mi) than US-supplied HIMARS missiles (80 km/50 mi).
Sources: en.wikipedia.org
Crystal induced arthritis (gout, and pseudogout) – usually involves particular joints (knee, MTP1, heels) and can be distinguished with an aspiration of joint fluid if in doubt. Redness, asymmetric distribution of affected joints, pain occurs at night, and the starting pain lasts for less than an hour, with gout. Osteoarthritis – distinguished with X-rays of the affected joints and blood tests, older age, starting pain less than an hour, asymmetric distribution of affected joints, and pain worsens when using the joint for longer periods. Systemic lupus erythematosus (SLE) – distinguished by specific clinical symptoms and blood tests (antibodies against double-stranded DNA) One of the several types of psoriatic arthritis resembles RA – nail changes and skin symptoms distinguish between them Lyme disease causes erosive arthritis and may closely resemble RA – it may be distinguished by a blood test in endemic areas Reactive arthritis – asymmetrically involves heel, sacroiliac joints and large joints of the leg. It is usually associated with urethritis, conjunctivitis, iritis, painless buccal ulcers, and keratoderma blennorrhagica. Axial spondyloarthritis (including ankylosing spondylitis) – this involves the spine, although an RA-like symmetrical small-joint polyarthritis may occur in the context of this condition. Hepatitis C – RA-like symmetrical small-joint polyarthritis may occur in the context of this condition. Hepatitis C may also induce rheumatoid factor auto-antibodies. Rarer causes which usually behave differently but may cause joint pains:
The task of radioactive decontamination following the Baker nuclear test at Bikini Atoll during Operation Crossroads in 1946 was far more difficult than the U.S. Navy had prepared for. Though the task's futility became apparent and the danger to cleanup crews mounted, Colonel Stafford Warren, in charge of radiation safety, had difficulty persuading Vice Admiral William H. P. Blandy to abandon the cleanup and with it the surviving target ships. On August 10, Warren showed Blandy an autoradiograph made by a surgeonfish from the lagoon that was left on a photographic plate overnight. The film was exposed by alpha radiation produced from the fish's scales, evidence that plutonium, mimicking calcium, had been distributed throughout the fish. Blandy promptly ordered that all further decontamination work be discontinued. Warren wrote home, "A self X ray of a fish ... did the trick."
== Awards and honors == 2016, Dal Nogare Award, Chromatography Forum of the Delaware Valley 2015, Palmer Award, Minnesota Chromatography Forum 2012, Provost’s Award for Excellence in Mentoring, University of Pittsburgh 2008, Pittsburgh Award, American Chemical Society
Sources: en.wikipedia.org
1993/1223) Value Added Tax (General) (Amendment) (No. 4) Regulations 1993 (S.I. 1993/1224) Bromley and Greenwich (London Borough Boundaries) Order 1993 (S.I. 1993/1225) Medicines (Veterinary Drugs) (Renewal Applications for Licences and Animal Test Certificates) Regulations 1993 (S.I. 1993/1227) Beer Regulations 1993 (S.I. 1993/1228) Financial Services (Designated Countries and Territories) (Overseas Insurance Companies) Order 1993 (S.I. 1993/1237) Scottish Hospital Endowments Research Trust (Amendment) Regulations 1993 (S.I. 1993/1238) National Savings Bank (Investment Deposits) (Limits) (Amendment) Order 1993 (S.I. 1993/1239) Soft Drinks (Amendment) Regulations 1993 (S.I. 1993/1240) South West Regional Flood Defence Committee Order 1993 (S.I. 1993/1241) Social Security (Widow's Benefit and Retirement Pensions) Amendment Regulations 1993 (S.I. 1993/1242) Child Abduction and Custody (Parties to Conventions) (Amendment) Order 1993 (S.I. 1993/1243) Iraq (United Nations) (Sequestration of Assets) Order 1993 (S.I. 1993/1244) Iraq (United Nations) (Sequestration of Assets) (Dependent Territories) Order 1993 (S.I. 1993/1245) Treaty on Open Skies (Privileges and Immunities) Order 1993 (S.I. 1993/1246) Treaty on Open Skies (Privileges and Immunities) (Overseas Territories) Order 1993 (S.I. 1993/1247) Turks and Caicos Islands Constitution (Amendment) Order 1993 (S.I. 1993/1248) Income-related Benefits Schemes and Social Security (Recoupment) Amendment Regulations 1993 (S.I. 1993/1249) Access to Health Records (Northern Ireland) Order 1993 (S.I.
=== Metabolic detoxification === An animal's metabolism can produce harmful substances which it can then make less toxic through reduction, oxidation (collectively known as redox reactions), conjugation and excretion of molecules from cells or tissues. This is called xenobiotic metabolism. Enzymes that are important in detoxification metabolism include cytochrome P450 oxidases, UDP-glucuronosyltransferases, and glutathione S-transferases. These processes are particularly well-studied as part of drug metabolism, as they influence the pharmacokinetics of a drug in the body.
As the image denotes, during sphingosine synthesis, palmitoyl CoA and serine undergo a condensation reaction which results in the formation of 3-dehydrosphinganine. This product is then reduced to form dihydrospingosine, which is converted to sphingosine via the oxidation reaction by FAD.
== Pharmacology == The drug potentiates the tropomyosin receptor kinases TrkA, TrkB, and TrkC with EC50Tooltip half-maximal effective concentration values of 382 nM, 295 nM, and ~330 nM, respectively. As a positive allosteric modulator of TrkA and TrkB, ACD856 potentiates the effects of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). In addition to the tropomyosin receptor kinases, ACD856 is also a similarly potent positive allosteric modulator of certain other receptor tyrosine kinases, including the insulin-like growth factor 1 receptor (IGF1R) and the fibroblast growth factor receptor 1 (FGFR1). However, its efficacies at the IGF1R and FGFR1 were much lower than at the TrkA, TrkB, and TrkC. In animals, ACD856 has been found to reverse scopolamine- and dizocilpine (MK-801)-induced memory impairment, to improve age-related memory deficits, and to have sustained antidepressant-like activity. It has also been reported to possess neuroprotective properties. In humans, the drug has been shown to cross the blood–brain barrier and to induce dose-dependent changes in electroencephalogram parameters. No significant tolerability or safety concerns have been identified in preclinical research or phase 1 clinical trials. The drug's clinical pharmacokinetics have been characterized and its elimination half-life is approximately 19 hours.
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.
No naturally occurring free form of the peptide has been described. The four-amino-acid sequence can appear as a fragment within larger proteins, but that is not the same as the intact compound being present as a circulating molecule. Materials used in research are synthetic.
Purity is usually checked by reverse-phase high-performance liquid chromatography, which separates the target peptide from related impurities. Mass spectrometry is commonly used alongside it to confirm molecular mass. Some suppliers also provide amino acid analysis for additional sequence confirmation.
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.