Everything below concerns Research chemical. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-09-17. Numbers and descriptions here follow the published literature rather than marketing material.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Electrospray or MALDI mass spectrometry | Observed mass compared with theoretical 390.35 Da |
| Purity specification | 95 percent or greater by RP-HPLC | Common convention for research-grade peptide |
| Counter-ion | Acetate or trifluoroacetate | Affects net peptide content of a weighed sample |
| Solution storage | −80 °C as single-use aliquots | Repeated freeze–thaw cycles accelerate loss |
| Main degradation route | Aspartimide formation at Asp-Gly | Produces isoaspartate and related species |
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.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
Published studies on epitalon are dominated by a small number of research groups, and independent replication in other laboratories remains limited. Proposed mechanisms include activation of telomerase and modulation of melatonin rhythms, but the evidence for either rests mainly on cell cultures and animal models. Whether the peptide produces comparable effects in humans is an open question, and the absence of large controlled trials means the literature is best read as exploratory rather than settled.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
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.
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.
== Personal life and death == Concert dates in support of Sheik's 2011 album Covers 80s were canceled when Sheik sought treatment for alcoholism. In a message to fans on his Tumblr blog, Sheik noted that he had entered a treatment center on the same day his latest album was released and had told his staff, "My record is coming out and I'm checking in." Sheik had a daughter with his wife Nora Ariffin, an actress turned realtor. He practiced Nichiren Buddhism and was a member of the U.S. branch of the worldwide Buddhist association Soka Gakkai International. On September 16, 2026, Sheik was reported by his family on his Instagram page to be hospitalized in "critical but stable condition". He died the following day from heart and organ failure leading to cardiac arrest in New York City, at the age of 56.
However, this occurs mostly in prostate cancer patients who take very high doses of cyproterone acetate; liver toxicity has not been reported in transgender women. Cyproterone acetate also has a variety of other adverse effects, such as fatigue and weight gain, and risks, such as blood clots and benign brain tumors, among others. High dosages of cyproterone-based medication have been linked with meningioma. Periodic monitoring of liver enzymes and prolactin levels may be advisable during cyproterone acetate therapy. Medroxyprogesterone acetate is a progestin that is related to cyproterone acetate and is sometimes used as an alternative to it. It is specifically used as an alternative to cyproterone acetate in the United States, where cyproterone acetate is not approved for medical use and is unavailable. Medroxyprogesterone acetate suppresses testosterone levels in transgender women similarly to cyproterone acetate. Oral medroxyprogesterone acetate has been found to suppress testosterone levels in men by about 30 to 75% across a dosage range of 20 to 100 mg/day. In contrast to cyproterone acetate however, medroxyprogesterone acetate is not also an androgen receptor antagonist. Medroxyprogesterone acetate has similar side effects and risks as cyproterone acetate, but is not associated with liver problems. Numerous other progestogens and by extension antigonadotropins have been used to suppress testosterone levels in men and are likely useful for such purposes in transgender women as well.
== Etymology == The word "lich" is derived from the Old English līċ, meaning "corpse". It is cognate with modern German Leiche, modern Danish lig, and modern Dutch lijk, all of which also mean "corpse".
Sources: en.wikipedia.org
=== Intramucosal nevi === An intramucosal nevus is a nevus within the mucosa as found in for example the mouth and genital areas. In the mouth, they are found most frequently on the hard palate. They are typically light brown and dome-shaped. Intramucosal nevi account for 64% of all reported case of oral nevi.
A diagnosis of BPD in adolescence can indicate the persistence of the disorder into adulthood, with outcomes varying among individuals. Some maintain a stable diagnosis over time, while others may not consistently meet the diagnostic criteria. Early diagnosis helps develop effective treatment plans, including family therapy, to support adolescents with BPD.
XXXXVIII Panzer Corps (General of Panzer Troops Rudolf Veiel): 14th Panzer Division, 29th Motorized Division, (24th Panzer Division from 6th Army on 14 Aug) IV Army Corps (General of Infantry Viktor von Schwedler): 94th Infantry Division, 371st Infantry Division, (297th Infantry-Division from 6th Army on 14 Aug) Romanian VI Army Corps (Lieutenant General Corneliu Dragalina): Romanian 1st Infantry Division, 2nd Infantry Division, 4th Infantry Division, 20th Infantry Division Army Group B's objective was to anchor itself on the Volga while Army Group A drove into the oil fields of the Caucasus. The 4th Panzer Army approached Stalingrad from the south while the 6th Army approached it from the west. Their aim was to meet up at Stalingrad and encircle the Soviet 62nd and 64th armies outside the city. The 6th Army was faced by a strong counterattack by the Soviet forces and failed to meet up with the 4th Panzer Army for three crucial days, allowing the two Soviet armies to withdraw into Stalingrad. The 4th Panzer Army guarded the outside perimeter of Stalingrad while the 6th Army was engaged in the battle to capture the city. For over two months, the 6th Army was embroiled in vicious fighting in the city; though it was able to take over 90% of the city, it was unable to destroy the last pockets of resistance. On 19 November 1942, the Red Army launched Operation Uranus, a counter-offensive which encircled the entire 6th Army and the 24th Panzer Division of the 4th Panzer Army. The 4th Panzer Army tried and failed to break the encirclement of Stalingrad in Operation Winter Storm.
== Signs and symptoms == Most individuals with G6PD deficiency are asymptomatic. When it induces hemolysis, the effect is usually short-lived. Most people who develop symptoms are male, due to the X-linked pattern of inheritance, but female carriers can be affected due to unfavorable lyonization or skewed X-inactivation, where random inactivation of an X chromosome in certain cells creates a population of G6PD-deficient red blood cells coexisting with unaffected red blood cells. A female with one affected X chromosome will show the deficiency in approximately half of her red blood cells. However, in some cases, including double X-deficiency, the ratio can be much more than half, making the individual almost as sensitive as males. Red blood cell breakdown (also known as hemolysis) in G6PD deficiency can manifest in many ways, including the following:
Sources: en.wikipedia.org
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.
Yes. Trifluoroacetate and acetate ions remain associated with the peptide after purification, so a weighed quantity of powder contains less peptide than the nominal mass suggests. Certificates that report net peptide content rather than raw weight are more directly comparable between suppliers.
Dilute aqueous solutions are less stable than the dry powder and are usually aliquoted and frozen to avoid repeated freeze–thaw cycles. Lyophilised material is best stored desiccated at −20 °C, protected from light. Working solutions are typically prepared fresh from a frozen aliquot.
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.