A practical reference on tetrapeptide: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-11-10 and is reviewed periodically as new material appears.
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
Epitalon is a synthetic tetrapeptide whose sequence is alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. It was developed in Russia during the 1980s and 1990s by investigators associated with the St. Petersburg Institute of Bioregulation and Gerontology, who studied short peptides as regulators of gene expression and tissue function. The alternative spelling epithalon appears interchangeably in the literature, and the two names refer to the same molecule. Outside Russia it is encountered chiefly as a research chemical rather than a licensed medicine, and it holds no approval from the United States Food and Drug Administration or the European Medicines Agency.
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.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Ala-Glu-Asp-Gly | Often abbreviated AEDG in research literature |
| Common synonyms | Epithalon, epitalon, AEDG | Spelling variants refer to the same tetrapeptide |
| Molecular formula | C14H22N4O9 | Theoretical monoisotopic mass near 390.35 Da |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility class | Freely soluble in water | Hydrophilic peptide; dissolves in aqueous buffer |
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.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
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.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
== Story == Medea is centered on Medea's calculated desire for revenge against her unfaithful husband. Medea is of divine descent and has the gift of prophecy. She married Jason and used her magic powers and advice to help him find and retrieve the golden fleece. The play is set in Corinth some time after Jason's quest for the Golden Fleece, where he met Medea. The play begins with Medea in a blind rage towards Jason for arranging to marry Glauce, the daughter of king Creon. The nurse, overhearing Medea's grief, fears what she might do to herself or her children. Creon, in anticipation of Medea's wrath, arrives and reveals his plans to send her into exile. Crouching at Creon's feet, Medea begs him in the name of her children to allow her one day's delay. At this Creon is moved and grants to her one more day in Corinth. Medea's unexpected power of persuasion or even of fascination lies in her change of attitude: instead of preaching to Creon about the unpopularity of the sophoi she plays the role of a desperate mother, needing one day to prepare for exile. Medea is aware of the humiliating quality of this tactic, but she justifies it on the grounds of a gain and of her need to remain in Corinth: "Do you think that I would ever have flattered that man unless I had some gain to make or some device to execute? I wouldn't have even spoken or touched him with my hands". In the next scene Jason arrives to explain his rationale for his apparent betrayal.
Multiple cases were filed in the Administrative Court and the Constitutional Court, asking for the election results to be nullified and new elections held. Politicians from the People's Party and the Thai Sang Thai Party also filed cases against the Election Commission in Criminal Court for misconduct. Observers noted that new ballots used in repeat elections on 22 February no longer featured serial numbers on the counterfoil. The Election Commission filed cases against citizen observers at the 22 February election, accusing them of election interference. Critics, including senator Nantana Nantavaropas, said this amounted to a strategic lawsuit against public participation (SLAPP). The Asian Network for Free Elections, which observed the election, said the unique codes engaged Article 25 of the International Covenant on Civil and Political Rights, section 85 of the constitution and section 84 of the Organic Act on the Election of Members of the House of Representatives. The Ombudsman decided to forward the case to the Constitutional Court on 13 March. On 18 March, the court voted 6–3 to accept the Ombudsman's petition and consider the case. The court scheduled its ruling for 28 September 2026 on whether the codes breached the constitutional guarantee of ballot secrecy, a finding that could void the election.
In molecular biology, and more importantly high-throughput DNA sequencing, a chimera is a single DNA sequence originating when multiple transcripts or DNA sequences get joined. Chimeras can be considered artifacts and be filtered out from the data during processing to prevent spurious inferences of biological variation. However, chimeras should not be confused with chimeric reads, which are generally used by structural variant callers to detect structural variation events and are not always an indication of the presence of a chimeric transcript or gene. In a different context, the deliberate creation of artificial chimeras can also be a useful tool in molecular biology. For example, in protein engineering, "chimeragenesis" (forming chimeras between proteins that are encoded by homologous cDNAs) is one of the "two major techniques used to manipulate cDNA sequences". For gene fusions that occur through natural processes, see chimeric genes and fusion genes.
In addition, if a piece of wood is used for multiple purposes, there may be a significant delay between the felling of the tree and the final use in the context in which it is found. This is often referred to as the "old wood" problem. One example is the Bronze Age trackway at Withy Bed Copse, in England; the trackway was built from wood that had clearly been worked for other purposes before being re-used in the trackway. Another example is driftwood, which may be used as construction material. It is not always possible to recognize re-use. Other materials can present the same problem: for example, bitumen is known to have been used by some Neolithic communities to waterproof baskets; the bitumen's radiocarbon age will be greater than is measurable by the laboratory, regardless of the actual age of the context, so testing the basket material will give a misleading age if care is not taken. A separate issue, related to re-use, is that of lengthy use, or delayed deposition. For example, a wooden object that remains in use for a lengthy period will have an apparent age greater than the actual age of the context in which it is deposited.
== Side effects == The most common side effect in all insulin analogues is low blood sugar, while in more serious cases, side effects may include low blood potassium. Insulin allergies are also a concern, although they are not prevalent, affecting only about 2% of people in some form. Insulin analogues are generally considered safe during pregnancy, and many are used in the treatment of gestational diabetes.
Sources: en.wikipedia.org
Because silent mutations do not alter protein function they are often treated as though they are evolutionarily neutral. Many organisms are known to exhibit codon usage biases, suggesting that there is selection for the use of particular codons due to the need for translational stability. Transfer RNA (tRNA) availability is one of the reasons that silent mutations might not be as silent as conventionally believed. There is a different tRNA molecule for each codon. For example, there is a specific tRNA molecule for the codon UCU and another specific for the codon UCC, both of which code for the amino acid serine. In this instance, if there was a thousand times less UCC tRNA than UCU tRNA, then the incorporation of serine into a polypeptide chain would happen a thousand times more slowly when a mutation causes the codon to change from UCU to UCC. If amino acid transport to the ribosome is delayed, translation will be carried out at a much slower rate. This can result in lower expression of a particular gene containing that silent mutation if the mutation occurs within an exon. Additionally, if the ribosome has to wait too long to receive the amino acid, the ribosome could terminate translation prematurely.
== Current status == Beavis is the founder of Beavis Informatics Ltd, a Canadian company providing consulting services in the general area of mass spectrometry-based proteomics. He oversees the development and operation of the GPM & GPMDB projects.
== Cultural response == Though intended as a parody, the single popularized the valley girl stereotype nationwide. Following the single's release, there was a significant increase in "valleyspeak" slang usage, whether ironically spoken or not. In particular, the film Valley Girl (1983) capitalized on this cultural curiosity. Zappa expressed concern that, despite his rich body of music, he was seen as a "novelty" artist because of songs like "Valley Girl" and "Don't Eat the Yellow Snow". At the time of the single's release, Moon said, "I am not a valley girl, but I guess that is my claim to fame." Mimi Pond created a comic book about the song, The Valley Girl's Guide to Life, which launched her career. A parody entitled "Valley Dudes" was recorded in 1982 by The Straight A's. On September 16, 2022 (3 months after the single's 40th anniversary), Universal Music Group (who acquired the Zappa catalogue in June of the same year) released an animated music video for the song.
A Cochrane review, updated 2023, stated that myo‐inositol has a potential beneficial effect of improving insulin sensitivity, which suggested that it may be useful for women in preventing gestational diabetes″. It has been suggested that for women who have had gestational diabetes, diet, exercise, education, and lifestyle changes between pregnancies may lower their chances of having gestational diabetes again in future pregnancies. For women with a normal BMI pre-pregnancy, light to moderate exercise for 30-60 minutes three times a week during pregnancy can decrease the occurrence of GDM. It was found that women who completed at least 600 MET-min/week of moderate intensity exercise can cause at least a 25% reduction in the odds of developing GDM. When studying the difference effects between aerobic and resistance training, it was found that there were no differences in fasting blood glucose levels, insulin utilization rate, or pregnancy outcomes. However, there was a better improvement in the 2-hour postprandial blood glucose level. The resistance training group was also more compliant with their workout program than the aerobic group. Based on this information, resistance training may be a better option for women with gestational diabetes, but doing both aerobic training and resistance training would be optimal.
Sources: en.wikipedia.org
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine–glutamate–aspartate–glycine, also written AEDG. It was developed in Russian gerontology research and is studied for proposed effects on telomerase, melatonin regulation, and neuroendocrine function. It is not an approved pharmaceutical in the United States or the European Union.
No. Epithalamin is a peptide-rich extract prepared from bovine pineal glands, while epitalon is a short synthetic peptide designed as a defined analogue of it. The synthetic version was intended to provide a reproducible molecule with some of the same proposed biological activity.
Telomere elongation and telomerase activation have been reported in cultured human somatic cells, but evidence from living human subjects is limited and has not been independently confirmed at scale. Reported findings come largely from small studies with differing designs, so the question remains open rather than settled.
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.