Epithalamin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-08-02. Where a claim depends on a specific study, the study is described rather than over-claimed.
Storage and handling follow conventional peptide practice. Lyophilized epitalon is typically kept refrigerated or frozen, protected from moisture and light, and allowed to equilibrate to room temperature before opening to avoid condensation. Once dissolved, aqueous solutions are usually stored cold and used within a short period, since dilute peptide solutions can support microbial growth and may slowly degrade. The absence of cysteine and methionine reduces, but does not eliminate, oxidation concerns during long-term storage.
Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Purity assessment | RP-HPLC | Reported as percent area, often ≥95% |
| Identity confirmation | Mass spectrometry | Observed mass compared with ~390 Da |
| Typical storage temperature | -20 °C or below | Lyophilized powder, desiccated |
| Reconstitution solvent | Sterile water or buffer | Acidic residues aid dissolution |
| Common synonyms | AEDG; epithalon | Spelling varies in literature |
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
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.
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.
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.
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.
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.
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.
Aromatic polyimides are synthesized by the reaction of dianhydrides with diamines, such as pyromellitic anhydride with p-phenylenediamine. It can also be accomplished using diisocyanates in place of diamines. Solubility considerations sometimes suggest use of the half acid-half ester of the dianhydride, instead of the dianhydride itself. Polymerization is accomplished by a two-stage process due to the insolubility of polyimides. The first stage forms a soluble and fusible high-molecular-weight poly(amic acid) in a polar aprotic solvent such as NMP or N,N-dimethylacetamide. The poly(amic aicd) can then be processed into the desired physical form of the final polymer product (e.g., film, fiber, laminate, coating) which is insoluble and infusible.
17 December Murder of Sara Sharif: Urfan Sharif, 43, and Beinash Batool, 30, the father and stepmother of Sara Sharif, are sentenced at the Old Bailey for 10-year-old Sara Sharif's murder. Sharif receives a minimum term of 40 years, while Batool is given 33 years, with Justice Cavanagh describing their crimes as "a campaign of torture" in which "the degree of cruelty is almost inconceivable". The girl's uncle, Faisal Malik, 29, is imprisoned for 16 years. Former Archbishop of Canterbury George Carey resigns as a priest following a BBC investigation into the Church of England's handling of a sexual abuse case and revelations that he allowed a priest convicted of sexual abuse to return to clerical duties. In Plymouth, a man is taken to hospital after being shot in the chest by an air rifle. Data from the Office for National Statistics indicates average pay increased at an annual rate of 5.2% between August and October 2024, the first increase for a year, and larger than expected. Train managers at Avanti West Coast vote to take strike action on New Year's Eve, 2 January, and every Sunday from 12 January until May after rejecting a deal aimed at resolving a dispute over rest day working. 18 December Office for National Statistics data indicates UK inflation rose to 2.6% in November, the second consecutive monthly increase. Deputy assistant commissioner Vicki Evans, senior national co-ordinator for Counter Terrorism Policing, warns that the UK faces a "smouldering" terror threat level with children as young as ten accessing extreme online material.
Nandrolone is the parent compound of a large group of anabolic steroids. Notable examples include the non-17α-alkylated trenbolone and the 17α-alkylated ethylestrenol (ethylnandrol) and metribolone (R-1881), as well as the 17α-alkylated designer steroids norboletone and tetrahydrogestrinone (THG). The following is list of derivatives of nandrolone that have been developed as anabolic steroids:
According to US Chamber of Commerce 70% of all illicit drug users are employed. Some industries have high rates of employee drug use such as construction (12.8%), repair (11.1%), and hospitality (7.9-16.3%).
Sources: en.wikipedia.org
The small intestine starts at the pyloric sphincter, and finishes at the ileocecal valve. Partially digested food starts to arrive in the small intestine as semi-liquid chyme, one hour after it is eaten. The stomach is half empty after an average of 1.2 hours. After four or five hours the stomach has emptied. In the small intestine, the pH becomes crucial; it needs to be finely balanced in order to activate digestive enzymes. The chyme is very acidic, with a low pH, having been released from the stomach and needs to be made much more alkaline. This is achieved in the duodenum by the addition of bile from the gall bladder combined with the bicarbonate secretions from the pancreatic duct and also from secretions of bicarbonate-rich mucus from duodenal glands known as Brunner's glands. The chyme arrives in the intestines having been released from the stomach through the opening of the pyloric sphincter. The resulting alkaline fluid mix neutralises the gastric acid which would damage the lining of the intestine. The mucus component lubricates the walls of the intestine.
Having personally experienced a confused night action off Guadalcanal, Lee was not enthusiastic about a night engagement with Japanese surface forces, believing that his crews were not adequately trained for it. Shortly after learning Lee's opinion, Mitscher requested permission from Spruance to move TF 58 west during the night, to reach a launch position at dawn that would allow for a maximum aerial assault on the enemy force. Spruance considered for an hour, then refused Mitscher's request. Mitscher's staff was disappointed with Spruance's decision. Burke later commented: "We knew we were going to have hell slugged out of us in the morning. We knew we couldn't reach them. We knew they could reach us." Spruance's decision was influenced by his orders from Nimitz, who had made it clear that the protection of the invasion fleet was the primary mission of TF 58. Spruance had concerns that the Japanese would attempt to draw his main fleet away from the Marianas with a diversionary force while slipping an attack force in to destroy the landing fleet. Locating and destroying the Japanese fleet was not his primary objective, and he was unwilling to allow the main strike force of the Pacific Fleet to be drawn westward, away from the amphibious forces. Mitscher accepted the decision without comment. Spruance's decision in this matter, although subsequently criticized, was certainly justified; by this point in the war, it was well known that Japanese operational plans frequently relied on the use of decoys and diversionary forces.
Halliwell B, Watt F, Minqin R. (2023) Iron and atherosclerosis: Lessons learned from rabbits relevant to human disease. Free Radic. Biol. Med. 209, 165–170. Yau YF, Cheah IK, Mahendran R, Tang RMY, Chua RY, Goh RES, Feng L, Li J, Kua EH, Chen C, Halliwell B. (2024) Investigating the efficacy of ergothioneine to delay cognitive decline in mild cognitively impaired subjects: A pilot study. J. Alzheimer's Disease 102, 841–854.
Sources: en.wikipedia.org
== Uses == Flowers brighten and enhance the human environment. Cut flowers and flower arrangements with cut greens bring the outdoors indoors. Many home gardeners harvest flowers from their own gardens, to increase their everyday enjoyment. Garden cut flowers are also used to enhance gatherings of family and friends. These are often enhanced with the addition foliage from other plants. In some cultures, a major use of cut flowers is for worship; this can be seen especially in south and southeast Asia. Sometimes the flowers are picked rather than cut, without any significant leaf or stem. Such flowers may be used for wearing in hair, or in a button-hole. Masses of flowers may be used for sprinkling, in a similar way to confetti. Garlands, wreaths and bouquets are major value added products in many markets. It is common for cut flowers and cut greens to be placed in a vase. Common uses are informal and formal bouquets in a glass vase for hospital visits, wedding bouquets, wedding arrangements, funeral casket displays, large arrangements in hotel lobbies and party venues, boutonnieres, wreaths, and garlands. Cut flowers are used at flower shows at garden clubs throughout the world and flower competitions at county and state fairs in the US. Cut flowers are a common gift for family or friends or just a day brightener on a work station or kitchen table.
=== Applications for ecosystem process analysis === Isotopic tracers are used to examine processes in natural systems, especially terrestrial and aquatic environments. In soil science 15N tracers are used extensively to study nitrogen cycling, whereas 13C and 14C, stable and radioisotopes of carbon respectively, are used for studying turnover of organic compounds and fixation of CO2 by autotrophs. For example, Marsh et al. (2005) used dual labeled (15N- and 14C) urea to demonstrate utilization of the compound by ammonia oxidizers as both an energy source (ammonia oxidation) and carbon source (chemoautotrophic carbon fixation). Deuterated water is also used for tracing the fate and ages of water in a tree or in an ecosystem.
=== The beginning of antibody imaging === Owing to their high affinity and specificity, antibodies have been considered as suitable vehicles for imaging and therapeutics, since the beginning of the 20th Century. The first radiolabelled antibodies were used in the early 1950s and got used for cancer therapy, but it took roughly two more decades before it was demonstrated that they target human tumour associated antigens in cancer patients. Due to the hybridoma technology in 1975, monoclonal (murine) antibodies could easily be produced in practical amounts, consequently the number of studies increased drastically. However, these types of antibodies turned out to be quite troublesome, due to the triggering of the human anti-murine antibody response. Consequently chimeric, humanised and human monoclonal antibodies have been created, produced and get used nowadays. Owing to the high molecular weight of antibodies and the Fc domain of the antibody, a slow clearance from the blood and non-target tissue occurs, which results in low tumour-to-blood and tumour-to-muscle ratios. Because of this, antibodies which are going to be used for imaging purposes need to be labelled with radionuclides that have a long half-life, which increases the radiation dose to the patient. This consequently encouraged the development of lower molecular weight antibodies and resulted in the development of minibodies, diabodies, single chain variable fragments (scFv) and single domain fragments (Fv).
Sources: en.wikipedia.org
Identity is normally confirmed by mass spectrometry, which checks the measured mass against the expected value near 390 daltons. Reverse-phase high-performance liquid chromatography is used alongside it to assess purity. Amino acid analysis can provide additional composition data.
The powder is generally kept refrigerated or frozen, protected from light and moisture. Vials should reach room temperature before opening to prevent condensation. Reconstituted solutions are usually stored cold and used within a limited window because dilute solutions can degrade or support microbial growth.
Epitalon is not an approved drug in major Western regulatory jurisdictions. Its legal status differs between countries, and it is often distributed as a research chemical. This means product documentation and purity vary considerably between suppliers.
It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.