A practical reference on AEDG: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-09-19. Anything still debated is marked as such rather than presented as settled.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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.
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.
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.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
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.
Reference material is normally supplied as a lyophilised powder in a sealed vial. Product literature typically recommends storage at minus twenty degrees Celsius or colder, protected from light and moisture. Freeze-thaw cycling is usually avoided because repeated condensation can introduce water into the vial. Working solutions are commonly prepared fresh, aliquoted, and kept cold for short periods rather than stored at ambient temperature. Labelling the date of opening helps track how long a vial has been in use.
According to the Federal Office for Radiation Protection, the few available results from investigations in the frequency range of active whole-body scanners that work with millimeter wave or terahertz radiation do not yet allow a conclusive assessment from a radiation protection perspective (as of 24 May 2017). In the vicinity of the plant, where employees or other third parties may be present, the limit value of the permissible annual dose for a single person in the population of one millisievert (1 mSv, including pregnant women and children) is not exceeded, even in the case of permanent presence. In the case of X-ray scanners for hand luggage, it is not necessary to set up a radiation protection area by Section §19 RöV, as the radiation exposure during a hand luggage check for passengers does not exceed 0.2 microsievert (μSv), even under unfavorable assumptions. For this reason, employees involved in baggage screening are not considered to be occupationally exposed to radiation in accordance with Section §31 X-ray Ordinance and therefore do not have to wear a dosimeter.
==== Nested PCR ==== The use of nested polymerase chain reaction (nested PCR) was evaluated to determine sex by detecting a Y chromosome specific signal in the cffDNA from maternal plasma. Nested PCR detected 53 of 55 male fetuses. The cffDNA from the plasma of 3 of 25 women with female fetuses contained the Y chromosome-specific signal. The sensitivity of nested PCR in this experiment was 96 percent. The specificity was 88 percent.
As the classification is most often used today, the oldest American think tank is the Carnegie Endowment for International Peace, founded in 1910. The Institute for Government Research, which later merged with two organizations to form the Brookings Institution, was formed in 1916. Other early twentieth century organizations now classified as think tanks include the Hoover Institution (1919), The Twentieth Century Fund (1919, and now known as the Century Foundation), the National Bureau of Economic Research (1920), the Council on Foreign Relations (1921), and the Social Science Research Council (1923). The Great Depression and its aftermath spawned several economic policy organizations, such as the National Planning Association (1934), the Tax Foundation (1937), and the Committee for Economic Development (1943). In collaboration with the Douglas Aircraft Company, the Air Force set up the RAND Corporation in 1946 to develop weapons technology and strategic defense analysis. The Hudson Institute is a conservative American think tank founded in 1961 by futurist, military strategist, and systems theorist Herman Kahn and his colleagues at the RAND Corporation. Recent members include Mike Pompeo, the former secretary of state under Donald Trump who joined in 2021. More recently, progressive and liberal think tanks have been established, most notably the Center for American Progress and the Center for Research on Educational Access and Leadership (CREAL). The organization has close ties to former United States President Barack Obama and other prominent Democrats.
==== Income distribution ==== The duration and expansion of the national conflict has had a significant impact on the distribution of income and wealth in Colombia. According to an investigation by the CEDE of the University of the Andes (Universidad de los Andes), "as a result of the displacement, the displaced households have left behind a little more than four million hectares, which correspond to 6.7 times of the total hectares granted by the program of Agrarian Reform during the period between 1993 and 2000, and represent a total value of $ 2.6 billion." In this context, the enormous concentration of rural property in the hands of a few individuals is not only the result of the purchase of land by drug traffickers and the illegal appropriation by groups outside the law, but also the consequence of acquisition of properties devalued due to the armed conflict. It is estimated that 1.3% of the owners control 48% of the best lands. A study carried out by the United Nations Development Program (UNDP) states that the Colombian conflict has had a negative effect on the income of the population. According to this study, because of the conflict, Colombia has lost 17% of its per capita income in the last ten years. That is to say, "[...] the money wasted every year corresponds to about 4.6 times what the community welfare homes programs, children's homes and school restaurants of the social support network cos."
Sources: en.wikipedia.org
Historically, Japanese consumption of animal products primarily focused on seafood. Influenced by Buddhist precepts against killing (sesshō) and the Shinto reverence for rice cultivation, meat from mammals and birds was often considered impure (kegare) and rarely eaten. Although domesticated chickens arrived in Japan during the Yayoi period, imperial edicts, such as those by Emperor Tenmu and Emperor Shōmu, forbade the killing and eating of certain animals, including chickens, and eggs were likely avoided as well. During the Sengoku period and Edo period, contact with Europeans, particularly in Western Japan, introduced meat-eating habits and the consumption of eggs. Namban confectionery using eggs, such as castella and bōro, also arrived. An early dish resembling TKG, called Tamago meshi (玉子飯, egg rice), appears in the 1805 cookbook Shirōto Hōchō (素人包丁, Amateur Cooking). It involved pouring beaten egg over cooked rice and steaming it. In 1838, records from the Nabeshima clan (Onji Nikki) mention "Odonburi Namatamago" (御丼 生玉子, bowl of rice [with] raw egg) being served to guests. The first person known to have eaten TKG in its modern, raw form was Kishida Ginkō (1833–1905), a pioneering journalist, around 1877. He reportedly recommended the dish to others. According to a 1927 magazine article describing Ginkō's habits, he seasoned it with salt and chili pepper (bansho). Eggs were a luxury during the food shortages after World War II, but became widely affordable from the 1950s onwards. TKG then gained popularity for its taste and nutritional value.
====== Stimulation of beta-defensin production ====== SeV is a very effective stimulant of expression of human beta-defensin-1 (hBD-1). This protein is a member of the beta-defensin family of proteins that bridges innate and adaptive immune responses to a pathogen infection. In response to SeV infection, the production of hBD-1 mRNA and protein increases 2 hours after exposure to the virus in purified plasmacytoid dendritic cells or in PBMC.
=== Financial performance === Medpace Holdings, Inc. has demonstrated strong revenue and income growth since going public in 2016, maintaining a steady upward trajectory in operating and net income over the last several years.
=== Chemi-ionization === Chemi-ionization is the formation of an ion through the reaction of a gas phase atom or molecule with an atom or molecule in an excited state. Chemi-ionization can be represented by
== See also == Substituted phenylethylpyrrolidine α-Pyrrolidinopropiophenone (α-PPP) α-Pyrrolidinobutiophenone (α-PBP) α-Pyrrolidinopentiophenone (α-PVP) α-Pyrrolidinohexiophenone (α-PHP) α-Pyrrolidinoheptaphenone (α-PHPP)
Sources: en.wikipedia.org
Many surgical procedures have been developed to create a neovagina, but none of them are ideal. Surgical intervention should only be considered after non-surgical pressure dilation methods have failed to produce a satisfactory result. A study in 2025 claims that vaginoplasty is not recommended in CAIS individuals. Neovaginoplasty can be performed using skin grafts, a segment of bowel, ileum, peritoneum, an absorbable adhesion barrier (Intercede, made by Johnson & Johnson), buccal mucosa, amnion, dura mater. or with the support of vaginal stents/expanders. Success of such methods should be determined by sexual function, and not just by vaginal length, as has been done in the past. Ileal or cecal segments may be problematic because of a shorter mesentery, which may produce tension on the neovagina, leading to stenosis. The sigmoid neovagina is thought to be self-lubricating, without the excess mucus production associated with segments of small bowel. Vaginoplasty may create scarring at the introitus (the vaginal opening), which requires additional surgery to correct. Vaginal dilators are required postoperatively to prevent vaginal stenosis from scarring. Inflatable vaginal stents are placed in the vagina deflated and then gently inflated. Other complications include bladder and bowel injuries. Yearly exams are required as neovaginoplasty carries a risk of carcinoma, although carcinoma of the neovagina is uncommon. Neither neovaginoplasty nor vaginal dilation should be performed before puberty.
==== Reoxygenation of intolerant animals ==== When oxygen re-enters the system, animals are faced with a different set of problems. Since ATP was used up during the anoxic period, it leads to a lack of ADP within the system. This is due to ADP's natural degradation into AMP, resulting in ADP being drained from the system. With no ADP in the system, Complex V is unable to start, meaning the protons will not flow through it to enter the matrix. Due to Complex V's reversal during anoxia, the proton gradient has become hyperpolarized (where the proton gradient is highly positively charged). Another factor in this problem is that succinate built up during anoxia, so when oxygen is reintroduced, succinate donates electrons to Complex II. The hyperpolarized gradient and succinate buildup leads to reverse electron transport, causing oxidative stress, which can lead to cellular damage and diseases.
HMRC reverses the plan for its self-assessment helpline, announced the previous day, following criticism from the public and MPs. The Senedd approves Vaughan Gething as the next First Minister of Wales. The London Clinic, where the Princess of Wales underwent abdominal surgery, announces that "any breach" of patient confidentiality will be investigated after reports a member of staff tried to access her private records. 21 March The Bank of England leaves interest rates unchanged at 5.25%, for the fifth time in a row. A report published by the Parliamentary and Health Service Ombudsman recommends women born in the 1950s who were affected by the 2010 changes to the state pension age should receive compensation of between £1,000 and £2,900. 22 March Following media speculation about her health, it is revealed that the Princess of Wales has been diagnosed with cancer and is undergoing treatment. Wetherspoons reports an eightfold increase in pre-tax profits during the first six months of the 2023–24 financial year. 23 March – A report compiled by the Resolution Foundation indicates a rise in the number of people leaving work due to long-term health conditions, with the number of people inactive due to long-term health conditions rising from 2.1 million in 2019 to 2.8 million in October 2023, the longest sustained rise since 1994–1998 when records began. The UK is also the only country in the G7 not to return to pre-pandemic employment levels.
== Management == There is no cure for Marfan syndrome, but life expectancy has increased significantly since the 1970s and is now similar to that of the average person. Regular checkups are recommended to monitor the health of the heart valves and the aorta. Marfan syndrome is treated by addressing each issue as it arises and, in particular, preventive medication even for young children to slow progression of aortic dilation. The goal of this treatment strategy is to slow the progression of aortic dilation and prevent any damage to heart valves by eliminating heart arrhythmias, minimizing the heart rate, and lowering the person's blood pressure.
Sources: en.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
Reversed-phase high-performance liquid chromatography with ultraviolet detection at 214 nanometres is the usual approach. Peak area percentage provides a purity figure relative to other components in the sample. Mass spectrometry is then applied to confirm identity.