This is a working overview of AEDG tetrapeptide, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-09-16 and is reviewed periodically as new material appears.
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.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
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.
Analytical characterization of epitalon relies on standard peptide methods. Reverse-phase high-performance liquid chromatography is used to assess purity, and mass spectrometry confirms identity by checking the observed mass against the expected value near 390 daltons. Amino acid analysis can verify composition. Because the peptide is short and hydrophilic, it elutes early on many reverse-phase columns, so method development often requires ion-pairing reagents to achieve adequate retention and resolution from related impurities.
| 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 |
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.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
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.
==== 2012 effective ban by China of Korean kimchi imports ==== Since 2012, the Chinese government has effectively banned the import of Korean kimchi through government regulations. Ignoring the standards of kimchi outlined by the Codex Alimentarius, China defined kimchi as a derivative of one of its own cuisines, called pao cai. However, due to significantly different preparation techniques from pao cai, kimchi has significantly more lactic acid bacteria through its fermentation process, which exceeds China's regulations. Since 2012, commercial exports of Korean kimchi to China has reached zero; the only minor amounts of exports accounting for Korean kimchi are exhibition events held in China.
German-occupied Poland was divided from 1939 into two regions: Polish areas annexed by Nazi Germany directly into the German Reich and areas ruled under a so-called General Government of occupation. The Poles formed an underground resistance movement and a Polish government-in-exile that operated first in Paris, then, from July 1940, in London. Polish-Soviet diplomatic relations, broken since September 1939, were resumed in July 1941 under the Sikorski–Mayski agreement, which facilitated the formation of a Polish army (the Anders' Army) in the Soviet Union. In November 1941, Prime Minister Sikorski flew to the Soviet Union to negotiate with Stalin on its role on the Soviet-German front, but the British wanted the Polish soldiers in the Middle East. Stalin agreed, and the army was evacuated there.[w] The organizations forming the Polish Underground State that functioned in Poland throughout the war were loyal to and formally under the Polish government-in-exile, acting through its Government Delegation for Poland. During World War II, hundreds of thousands of Poles joined the underground Polish Home Army (Armia Krajowa), a part of the Polish Armed Forces of the government-in-exile. About 200,000 Poles fought on the Western Front in the Polish Armed Forces in the West loyal to the government-in-exile, and about 300,000 in the Polish Armed Forces in the East under the Soviet command on the Eastern Front. The pro-Soviet resistance movement in Poland, led by the Polish Workers' Party, was active from 1941.
=== Chemistry === The maturation process causes four main chemical transformations to the tequila compounds: (1) decreasing of fusel oils by the char in barrels, which acts as an absorbing agent; (2) extraction of complex wood constituents by tequila, giving specific aroma and flavor to the final product; (3) reactions among the components of tequila, creating new chemical compounds; and (4) oxidation of the original contents of tequila and of those extracted from wood. The final results of these changes are increased concentrations of acids, esters and aldehydes, and a decrease in fusel oil concentration.
AMP deaminase deficiency (formally known as myoadenylate deaminase deficiency or MADD) is a metabolic myopathy which results in excessive AMP buildup brought on by exercise. AMP deaminase is needed to convert AMP into IMP in the purine nucleotide cycle. Without this enzyme, the excessive AMP buildup is initially due to the adenylate kinase (myokinase) reaction which occurs after a muscle contraction. However, AMP is also used to allosterically regulate the enzyme myophosphorylase (see Glycogen phosphorylase § Regulation), so the initial buildup of AMP triggers the enzyme myophosphorylase to release muscle glycogen into glucose-1-P (glycogen→glucose-1-P), which eventually depletes the muscle glycogen, which in turn triggers protein metabolism, which then produces even more AMP. In AMP deaminase deficiency, excess adenosine is converted into uric acid in the following reaction:
Sources: en.wikipedia.org
Retinol is made industrially via total synthesis using either a method developed by BASF or a Grignard reaction utilized by Hoffman-La Roche. The two major suppliers, DSM and BASF, are believed to use total synthesis. The world market for synthetic retinol is primarily for animal feed, leaving approximately 13% for a combination of food, prescription medication, and dietary supplement use. The first industrialized synthesis of retinol was achieved by the company Hoffmann-La Roche in 1947. In the following decades, eight other companies developed their own processes. β-Ionone, synthesized from acetone, is the essential starting point for all industrial syntheses. Each process involves elongating the unsaturated carbon chain. Pure retinol is extremely sensitive to oxidization and is prepared and transported at low temperatures and oxygen-free atmospheres. When prepared as a dietary supplement or food additive, retinol is stabilized as the ester derivatives retinyl acetate or retinyl palmitate. Before 1999, three companies, Roche, BASF, and Rhone-Poulenc controlled 96% of global vitamin A sales. In 2001, the European Commission imposed total fines of 855.22 Euros on these and five other companies for their participation in eight distinct market-sharing and price-fixing cartels that dated back to 1989. Roche sold its vitamin division to DSM in 2003. DSM and BASF have the major share of industrial production.
The two German states entered into a currency and customs union in July 1990, and on 3 October 1990, the German Democratic Republic dissolved and the re-established five East German Länder (as well as a unified Berlin) joined the Federal Republic of Germany, bringing an end to the East–West divide.
==== MeSH D12.776.964.970.600 – nucleocapsid proteins ==== MeSH D12.776.964.970.600.550 – capsid proteins MeSH D12.776.964.970.600.850 – viral core proteins MeSH D12.776.964.970.600.850.350 – gene products, gag MeSH D12.776.964.970.600.850.350.325 – fusion proteins, gag-pol MeSH D12.776.964.970.600.850.350.400 – hiv core protein p24 MeSH D12.776.964.970.600.850.375 – gene products, pol (gene) MeSH D12.776.964.970.600.850.375.325 – fusion proteins, gag-pol MeSH D12.776.964.970.600.850.375.335 – hiv integrase MeSH D12.776.964.970.600.850.375.340 – HIV protease MeSH D12.776.964.970.600.850.375.750 – RNA-directed DNA polymerase MeSH D12.776.964.970.600.850.375.750.375 – hiv-1 reverse transcriptase
The drug has been implicated in the deaths of people from all walks of life—from homeless individuals to professionals—including teens and young parents. Because of the rising deaths across the country, especially in British Columbia where 1,716 deaths were reported in 2020 and 1,782 from January to October 2021, Health Canada is putting a rush on a review of the prescription-only status of naloxone in an effort to combat overdoses of the drug. In 2018, Global News reported allegations that diplomatic tensions between Canada and China hindered cooperation to seize imports, with Beijing being accused of inaction. Fentanyl has been discovered for sale in illicit markets in Australia in 2017 and in New Zealand in 2018. In response, New Zealand experts called for wider availability of naloxone. In May 2019, China regulated the entire class of fentanyl-type drugs and two fentanyl precursors. Nevertheless, it remains the principal origin of fentanyl in the United States: Mexican cartels source fentanyl precursors from Chinese suppliers such as Yuancheng Group, which are finished in Mexico and smuggled to the United States.In the past several months before February 2025, China began scheduling fentanyl precursors that are internationally banned.
==== TRAP-seq ==== TRAP-seq is used to identify mRNAs being actively translated in a specific cell type within a tissue or other assortment of cells. The cell type of interest is engineered to express a ribosomal subunit fused to an epitope tag such as green fluorescent protein. After cell lysis, antibodies targeting the epitope are used to isolate mRNAs that are bound to the ribosomes containing the fusion proteins. This RNA is then converted to cDNA and sequenced. This technique specifically identifies mRNAs that are being translated in the cell type of interest.
Sources: en.wikipedia.org
Pharmacometrics is a field of study of the methodology and application of models for disease and pharmacological measurement. It uses mathematical models of biology, pharmacology, disease, and physiology to describe and quantify interactions between xenobiotics and patients (human and non-human), including beneficial effects and adverse effects.
==== Native Hawaiian or other Pacific Islander ==== The obesity rate for Native Hawaiian or other Pacific Islander adults (over 30 BMI) in the US in 2015 was 33.4%. No breakdown by sex was given for Native Hawaiian or other Pacific Islander adults in the CDC figures.
Therefore, the development of devices facilitating the transition from samples at higher pressure and in condensed phase (solid or liquid) into a vacuum system has been essential to develop MS as a potent tool for identification and quantification of organic compounds like peptides. MS is now in very common use in analytical laboratories that study physical, chemical, or biological properties of a great variety of compounds. Among the many different kinds of mass analyzers, the ones that find application in LC–MS systems are the quadrupole, time-of-flight (TOF), ion traps, and hybrid quadrupole-TOF (QTOF) analyzers.
Since the 1920s, pedoscopes have been installed in many shoe stores in North America and Europe, more than 10,000 in the U.S. alone, following the invention of Jacob Lowe, a Boston physicist. They were X-ray machines used to check the fit of shoes and to promote sales, especially to children. Children were particularly fascinated by the sight of their footbones. X-rays were often taken several times daily to evaluate the fit of different shoes. Most were available in shoe stores until the early 1970s. The energy dose absorbed by the customer was up to 116 rads, or 1.16 grays. In the 1950s, when medical knowledge of the health risks was already available, pedoscopes came with warnings that shoe-buyers should not be scanned more than three times a day and twelve times a year. By the early 1950s, several professional organizations issued warnings against the continued use of shoe-mounted fluoroscopes, including the American Conference of Governmental Industrial Hygienists, the American College of Surgeons, the New York Academy of Medicine, and the American College of Radiology. At the same time, the District of Columbia enacted regulations requiring that shoe-mounted fluoroscopes be operated only by a licensed physical therapist. A few years later, the state of Massachusetts passed regulations stating that these machines could only be operated by a licensed physician. In 1957, the use of shoe-mounted fluoroscopes was banned by court order in Pennsylvania.
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.
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.