Epithalamin is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-05-01. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Stability depends strongly on pH, temperature and the presence of oxygen and trace metals. Cleavage of the backbone proceeds faster under neutral to alkaline conditions, whereas acidic solutions tend to slow that reaction. The aspartate and glutamate side chains can undergo deamidation or imide formation over time, generating closely related impurities. Published stability data specific to epitalon are sparse, so the usable life of a given solution is best regarded as an open question that depends on buffer composition, concentration and storage temperature.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography with ultraviolet detection, frequently near 214 nanometers where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the observed molecular mass and helps separate the intact peptide from truncated or modified forms. Amino acid analysis or tandem mass spectrometry can establish residue order. Purity is commonly quoted as an area percentage, yet such values are method-dependent, and comparisons between laboratories require matching column, gradient and detection wavelength.
| 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 |
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.
The most widely cited claim is that epitalon activates telomerase and thereby extends telomere length. Supporting evidence comes largely from cultured human cells, where treatment was associated with increased telomerase activity and delayed replicative senescence. Telomerase activation is a biologically consequential effect, since the enzyme is largely silenced in most somatic cells. However, the route by which a short peptide would reach and act on the enzyme's regulatory machinery has not been established. Independent replication in human trials is scarce, so the link between cell-culture observations and whole-body aging remains an open question.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
These models state that each IR monomer possesses 2 insulin binding sites; site 1, which binds to the 'classical' binding surface of insulin: consisting of L1 plus αCT domains and site 2, consisting of loops at the junction of FnIII-1 and FnIII-2 predicted to bind to the 'novel' hexamer face binding site of insulin. As each monomer contributing to the IR ectodomain exhibits 3D 'mirrored' complementarity, N-terminal site 1 of one monomer ultimately faces C-terminal site 2 of the second monomer, where this is also true for each monomers mirrored complement (the opposite side of the ectodomain structure). Current literature distinguishes the complement binding sites by designating the second monomer's site 1 and site 2 nomenclature as either site 3 and site 4 or as site 1' and site 2' respectively. As such, these models state that each IR may bind to an insulin molecule (which has two binding surfaces) via 4 locations, being site 1, 2, (3/1') or (4/2'). As each site 1 proximally faces site 2, upon insulin binding to a specific site, 'crosslinking' via ligand between monomers is predicted to occur (i.e. as [monomer 1 Site 1 - Insulin - monomer 2 Site (4/2')] or as [monomer 1 Site 2 - Insulin - monomer 2 site (3/1')]). In accordance with current mathematical modelling of IR-insulin kinetics, there are two important consequences to the events of insulin crosslinking; 1. that by the aforementioned observation of negative cooperation between IR and its ligand that subsequent binding of ligand to the IR is reduced and 2.
=== Associated conditions === Researchers have implicated estrogens in various estrogen-dependent conditions, such as ER-positive breast cancer, as well as a number of genetic conditions involving estrogen signaling or metabolism, such as estrogen insensitivity syndrome, aromatase deficiency, and aromatase excess syndrome. Estrogens promote salt and water retention, which can lead to facial swelling and edema. High estrogen can amplify stress-hormone responses in stressful situations.
When a bioactive ligand with a known structure is to be screened against a protein with limited structural information, modeling is done with regard to ligand structure. Pharmacophore modeling identifies key electronic and structural features that are associated with therapeutic activity across similarly bioactive structural analogs, and accordingly requires large libraries with corresponding experimental data to enhance predictive power. Compound structures are superimposed virtually and common elements are scored on the basis of their tendency toward bioactivity. The move away from lock-and-key based modeling toward induced-fit based modeling has improved binding predictions but has also given rise to the challenge of modeling ligand flexibility, which requires building a database of conformational models and uses large amounts of data storage space. Another approach is the so-called on-the-fly method, in which conformational models are tested during the process of pharmacophore modeling, without a database; this method requires significantly less storage space at the cost of high computing time. A second challenge arises from the decision of how to superimpose analog structures. A common approach is to use a least-squares regression for superimposition, but this requires user-selected anchor points and therefore introduces human bias into the process. Pharmacophore models require training data sets, giving rise to another challenge—selection of the appropriate library of compounds to adequately train models.
=== ZonaZoo === Officially implemented in 2003, ZonaZoo is the official student section and student ticketing program for the University of Arizona Athletics. The ZonaZoo program is co-owned by the Associated Students of the University of Arizona (ASUA) and Arizona Athletics yet run by a team of individuals called the ZonaZoo Crew. In 2014, ESPN ranked ZonaZoo as the top student cheering section in the PAC 12 conference and in 2015, and in 2018, ZonaZoo received the Best Student Section of the Year award from the National Collegiate Student Section Association.
Sources: en.wikipedia.org
Stella Maris, the newly elected rector of St Andrews University, faces calls from students to apologise or resign after she said in an email that Palestinians had suffered "apartheid, siege, illegal occupation and collective punishment" during the Israel-Gaza war. 28 November – The Scottish Government publish a consultation for a new heating bill that will see the phasing out of gas boilers in Scotland, but the original start date of 2025 is expected to be delayed by three years.
Too high a concentration of the organic may cause the micelle to disperse, as it relies on hydrophobic effects for its formation. The maximum concentration of organic depends on the organic solvent itself, and on the micelle. This information is generally not known precisely, but a generally accepted practice is to keep the volume percentage of organic below 15–20%.
In 1896, Viennese dermatologist Leopold Freund (1868-1943) used X-rays to treat patients for the first time. He successfully irradiated the hairy nevus of a young girl. In 1897, Hermann Gocht (1869–1931) published the treatment of trigeminal neuralgia with X-rays, and Alexei Petrovich Sokolov (1854-1928) wrote about radiotherapy for arthritis in the oldest radiology journal, Advances in the field of X-rays (RöFo). In 1922, X-rays were recommended as safe for many diseases and for diagnostic purposes. Radiation protection was limited to recommending doses that would not cause erythema (reddening of the skin). For example, X-rays were promoted as an alternative to tonsillectomy. It was also boasted that in 80% of cases of diphtheria carriers, Corynebacterium diphtheriae was no longer detectable within two to four days. In the 1930s, Günther von Pannewitz (1900–1966), a radiologist from Freiburg, Germany, perfected what he called X-ray stimulation radiation for degenerative diseases. Low-dose radiation reduces the inflammatory response of tissues. Until about 1960, children with diseases such as ankylosing spondylitis or favus (head fungus) were irradiated, which was effective but led to increased cancer rates among patients decades later. In 1926, the American pathologist James Ewing (1866-1943) was the first to observe bone changes as a result of radiotherapy, which he described as radiation osteitis (now Osteoradionecrosis). In 1983, Robert E. Marx stated that osteoradionecrosis is radiation-induced aseptic bone necrosis.
In order to regulate the secretion of ACTH, many substances secreted within this axis exhibit slow/intermediate and fast feedback-loop activity. Glucocorticoids secreted from the adrenal cortex work to inhibit CRH secretion by the hypothalamus, which in turn decreases anterior pituitary secretion of ACTH. Glucocorticoids may also inhibit the rates of POMC gene transcription and peptide synthesis. The latter is an example of a slow feedback loop, which works on the order of hours to days, whereas the former works on the order of minutes. The half-life of ACTH in human blood is reported to be between ten and 30 minutes.
Alginic acid (E400), sodium alginate (E401), potassium alginate (E402), ammonium alginate (E403), calcium alginate (E404) - polysaccharides from brown algae Agar (E406, a polysaccharide obtained from red algae) Carrageenan (E407, a polysaccharide obtained from red seaweeds) Locust bean gum (E410, a natural gum polysaccharide from the seeds of the carob tree) Pectin (E440, a polysaccharide obtained from apple or citrus-fruit) Gelatin (E441, made by partial hydrolysis of animal collagen) Commercial jellies used in East Asian cuisines include the glucomannan polysaccharide gum used to make "lychee cups" from the konjac plants, and aiyu or ice jelly from the Ficus pumila climbing fig plant. Agar-agar produces a very clear gel with light residual taste. Gelatin sheets disperse easily with no residual taste, but powdered form may have some taste. Kappa carrageenan may include potassium chloride to improve the gelling process and produces a clear product with very little aftertaste. Iota carrageenan contains sodium chloride which improves gel formation. Sodium alginate produces a medium viscosity gel but may have some aftertaste. High-methoxy pectin is one of the most widely used gelling agents in food processing. It reacts with some sugars and acids and sometimes includes minerals to improve gelling process. Low-methoxy pectin reacts with calcium, and is used for the preparation of low sugar jams.
Sources: en.wikipedia.org
On 1 July 2016, Townsend joined Premier League club Crystal Palace on a five-year contract from Newcastle following their relegation to the Championship. Palace triggered his £13 million release clause just six months after he joined from Tottenham. He was originally assigned the number 17 shirt for his first season with Palace. However, after Yannick Bolasie left for Everton, Townsend was reassigned the vacant number 10 shirt previously worn by Bolasie. On 13 August 2016, Townsend made his debut in a 1–0 defeat against West Bromwich Albion in the Premier League. He scored his first goal for the club in a 4–1 victory over Stoke City in the league on 18 September. On 22 December 2018, Townsend scored a 30-yard volley in a 3–2 league win against Manchester City. His strike was later voted as Premier League Goal of the Month for December and Premier League Goal of the Season, as well as making the shortlist for the 2019 FIFA Puskás Award. In June 2021, Townsend was announced to be one of the players released by Crystal Palace at the end of the 2020–21 season, ending his five-year tenure with the side.
The main symptom of osteogenesis imperfecta is fragile, low mineral density bones; all types of OI have some bone involvement. In moderate and especially severe OI, the long bones may be bowed, sometimes extremely so. The weakness of the bones causes them to fracture easily—a study at the Endocrine Unit at the National Institute of Child Health in Karachi, Pakistan found an average of 5.8 fractures per year in untreated children. Fractures typically occur much less after puberty, but begin to increase again in women after menopause and in men between the ages of 60 and 80. Joint hypermobility is also a common sign of OI, thought to be because the affected genes are the same as those that cause some types of Ehlers–Danlos syndrome.
=== Potential degradation by sonication === Wang et al. reported that aqueous solutions of poloxamer 188 (Pluronic F-68) and poloxamer 407 (Pluronic F-127) sonicated in the presence or absence of multi-walled carbon nanotubes (MWNTs) can became highly toxic to cultured cells. Moreover, toxicity correlated with the sonolytic degradation of the polymers.
Born: Vyacheslav Gryaznov, Russian classical pianist; in Yuzhno-Sakhalinsk, Sakhalin, Russian SFSR, Soviet Union Filip Karadordević, U.S.-born Serbian businessman and heir to the throne of the abolished monarchy of Serbia and Yugoslavia as the eldest son of the former Crown Prince Alexander Karadordević, who was the only child of King Peter II of Yugoslavia; in Vienna, Virginia Died: Red Smith, 76, American sportswriter and columnist, died four days after he had published a column, which he headlined "Writing Less— and Better?" where he announced that he would be writing only three columns per week rather than four.
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.
The dry powder is typically held at -20 degrees Celsius or lower, protected from light and moisture. Allowing a sealed vial to reach room temperature before opening reduces condensation on its contents. Conditions stated on a supplier certificate of analysis take precedence over general guidance.