Everything below concerns Research chemical. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-08-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
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.
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.
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.
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.
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.
== Prognosis == An elevation in serum bilirubin level of more than 2 times ULN with associated transaminase rise indicates severe hepatotoxicity and is likely to lead to mortality in 10% to 15% of patients, especially if the offending drug is not stopped (Hy's Law). This is because it requires significant damage to the liver to impair bilirubin excretion, hence minor impairment (in the absence of biliary obstruction or Gilbert syndrome) would not lead to jaundice. Other poor predictors of outcome are old age, female sex, high AST.
==== Small nuclear RNA ==== Small nuclear RNA (snRNA) combines with proteins to form the spliceosome in the nucleus. The spliceosome is responsible for sensing and cutting introns out of pre-mRNA, which is one of the first steps of mRNA processing. The spliceosome is a large macromolecular complex. Quaternary structure allows snRNA to detect mRNA sequences that need to be excised.
=== Cardiovascular === Agmatine produces mild reductions in heart rate and blood pressure, apparently by activating both central and peripheral control systems via modulation of several of its molecular targets including: imidazoline receptors subtypes, norepinephrine release and NO production.
Sources: en.wikipedia.org
=== Therapy === Weight loss and problems in eating due to dysphagia and other muscle discoordination are common, making nutrition management increasingly important as the disease advances. Thickening agents can be added to liquids, as thicker fluids are easier and safer to swallow. Reminding the affected person to eat slowly and to take smaller pieces of food into the mouth may also be of use to prevent choking. If eating becomes too hazardous or uncomfortable, the option of using a percutaneous endoscopic gastrostomy is available. This feeding tube, permanently attached through the abdomen into the stomach, reduces the risk of aspirating food and provides better nutritional management. Assessment and management by speech-language pathologists with experience in Huntington's disease is recommended. People with Huntington's disease may see a physical therapist for noninvasive and nonmedication-based ways of managing the physical symptoms. Physical therapists may implement fall risk assessment and prevention, as well as strengthening, stretching, and cardiovascular exercises. Walking aids may be prescribed as appropriate. Physical therapists also prescribe breathing exercises and airway clearance techniques with the development of respiratory problems. Consensus guidelines on physiotherapy in Huntington's disease have been produced by the European HD Network. Goals of early rehabilitation interventions are prevention of loss of function.
Root: It is the attached part, consisting of the bulb in the middle and the crura, one crus on either side of the bulb. It lies within the superficial perineal pouch. The crus is attached to the pubic arch. Shaft: The pendulous part of the penis. It has two surfaces: dorsal (posterosuperior in the erect penis) and ventral or urethral (facing downwards and backwards on the flaccid penis). The ventral surface is marked by the penile raphe. The base of the shaft is supported by the suspensory ligament, which is attached to the pubic symphysis. Epithelium of the penis consists of the shaft skin, the foreskin (prepuce), and the preputial mucosa on the inside of it. The foreskin covers and protects the glans and shaft. The epithelium is not attached to the underlying shaft, so it is free to glide to and fro. The human penis is made up of three columns of erectile tissue: two corpora cavernosa lie next to each other (separated by a fibrous septum) on the dorsal side and one corpus spongiosum lies between them on the ventral side. These columns are surrounded by a fibrous layer of connective tissue called the tunica albuginea. The corpora cavernosa are innervated by lesser and greater cavernous nerves and form most of the penis containing blood vessels that fill with blood to help make an erection. The crura are the proximal parts of the corpora cavernosa. The corpus spongiosum is an erectile tissue surrounding the urethra. The proximal parts of the corpus spongiosum form the bulb and the distal ends form the glans penis.
RNA is synthesized from template DNA by RNA polymerase with messenger RNA (mRNA) serving as the intermediary biomolecule between DNA expression and protein translation. Because of its unique properties (such as its typically single-stranded nature and its 2' OH group) and its ability to adopt many different secondary/tertiary structures, both coding and noncoding RNAs have attracted attention in medicine. Research has begun to explore RNAs potential to be used for therapeutic benefit, and unique challenges have occurred during drug discovery and implementation of RNA therapeutics.
Sources: en.wikipedia.org
On September 15, 2012, David Wood, Deputy Director of the EBU Technology and Development Department (who chairs the ITU working group that created Rec. 2020), told The Hollywood Reporter that South Korea plans to begin test broadcasts of 4K UHDTV next year. Wood also said that many broadcasters have the opinion that going from HDTV to 8K UHDTV is too much of a leap and that it would be better to start with 4K UHDTV. In the same article, Masakazu Iwaki, NHK Research senior manager, said that the NHK plan to go with 8K UHDTV is for economic reasons since directly going to 8K UHDTV would avoid an additional transition from 4K UHDTV to 8K UHDTV. On October 18, 2012, the Consumer Electronics Association (CEA) announced that it had been unanimously agreed by the CEA's Board of Industry Leaders that the term "Ultra High-Definition", or "Ultra HD", would be used for displays that have a resolution of at least 8 megapixels with a vertical resolution of at least 2,160 pixels and a horizontal resolution of at least 3,840 pixels. The Ultra HD label also requires the display to have an aspect ratio of 16:9 or wider and to have at least one digital input that can carry and present a native video signal of 3840 × 2160 without having to rely on a video scaler. Sony announced they would market their 4K products as 4K Ultra High-Definition (4K UHD). On October 23, 2012, Ortus Technology Co., Ltd announced the development of the world's smallest 3840 × 2160 pixel LCD panel with a size of 9.6 inches (24 cm) and a pixel density of 458 px/in.
Tillman Gerngross (born November 15, 1963) is an Austro-American scientist. He is a professor of bioengineering at the Thayer School of Engineering at Dartmouth College, and an adjunct professor in the departments of biology and chemistry at Dartmouth. Gerngross has been an active inventor and to date his work has resulted in the founding of multiple companies (GlycoFi, Inc., Adimab LLC, Arsanis, Inc., Alector [Nasdaq:ALEC], Avitide, Inc., Amagma, Inc., Ankyra, and Adagio [Nasdaq:ADGI]) and over a dozen U.S. and international patents. Gerngross was elected a member of the National Academy of Engineering in 2017.
In a 1951 letter to the publisher Milton Waldman (1895–1976), Tolkien wrote about his intentions to create a "body of more or less connected legend", of which "[t]he cycles should be linked to a majestic whole, and yet leave scope for other minds and hands, wielding paint and music and drama". The hands and minds of many artists have indeed been inspired by Tolkien's legends. Personally known to him were Pauline Baynes (Tolkien's favourite illustrator of The Adventures of Tom Bombadil and Farmer Giles of Ham) and Donald Swann (who set the music to The Road Goes Ever On). Queen Margrethe II of Denmark created illustrations to The Lord of the Rings in the early 1970s. She sent them to Tolkien, who was struck by the similarity they bore in style to his own drawings. Tolkien was not implacably opposed to the idea of a dramatic adaptation, however, and sold the film, stage and merchandise rights of The Hobbit and The Lord of the Rings to United Artists in 1968. United Artists never made a film, although the director John Boorman was planning a live-action film in the early 1970s. In 1976 the rights were sold to Tolkien Enterprises, a division of the Saul Zaentz Company, and the first film adaptation of The Lord of the Rings was released in 1978 as an animated rotoscoping film directed by Ralph Bakshi with screenplay by the fantasy writer Peter S. Beagle. It covered only the first half of the story of The Lord of the Rings.
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
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.