This is a working overview of Epithalamin, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Storage temperature, solid | Approximately -20 C | Sealed, desiccated, protected from light |
| Typical identity method | Electrospray mass spectrometry | Protonated ion expected near 391 |
| Typical purity method | Reversed-phase HPLC | Ultraviolet detection near 214 nm |
| Common synonyms | Epithalon, epithalone, AEDG | Spelling variants appear in supplier catalogues |
| Solution stability | Days at 2-8 C | Hydrolysis and deamidation limit shelf life |
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.
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.
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.
=== Garn: Spacesickness === The garn is NASA's unit of measure for symptoms resulting from space adaptation syndrome, the response of the human body to weightlessness in space, named after US Senator Jake Garn, who became exceptionally spacesick during an orbital flight in 1985. If an astronaut is completely incapacitated by space adaptation syndrome, he or she is under the effect of one garn of symptoms.
The most common response was the possibility of a Metabolic Myopathy that translates to a metabolic muscle illness and are usually caused by the muscle's inability to breakdown nutrients. The muscles begin to break themselves down to yield energy. As Angel gets closer to possibly having a diagnosis, she starts to think about a possible future with children. She worries that if her disease is genetic, she wouldn't want to put her children at risk. A medical student from Italy reaches out to Dr. Sanders. She describes her 4th- year thesis on metabolic gene testing that could be beneficial in narrowing down a diagnosis. Angel travels to Turin, Italy for blood and urine testing. The testing showed that Angel had a normal metabolic gene profile, which eliminated many possible metabolic disorders. The physicians in Italy submitted her genomes into a sequencing trial that could take up to two months to process but could hopefully result with a diagnosis. After the two months, Angel receives a call from the Physician with a complete result and a solid diagnosis of Carnitine Palmitoyltransferase II Deficiency.
To "save succeeding generations from the scourge of war, which twice.. brought untold sorrow to mankind", the United Nations Charter was passed in 1945, and the Bretton Woods Conference set up a new system of integrated World Banking, finance and trade. Also, the Council of Europe, formed by the Treaty of London 1949, adopted a European Convention on Human Rights, overseen by a new transnational court in Strasbourg in 1950. Already in 1946, Winston Churchill, who had been defeated as UK Prime Minister in 1945, had called for a "United States of Europe", though this did not mean the UK would sever its ties to the Commonwealth. In 1950, the French Foreign Minister Robert Schuman proposed that, beginning with integration of French and German coal and steel production, there should be "an organisation open to the participation of the other countries of Europe", where "solidarity in production" would make war "not merely unthinkable, but materially impossible". The 1951 Treaty of Paris created the first European Coal and Steel Community (ECSC), signed by France, West Germany, Belgium, the Netherlands, Luxembourg and Italy, with Jean Monnet as its president. Its theory was simply that war would be impossibly costly if ownership and production of every country's economy was mixed together. It established an Assembly (now the European Parliament) to represent the people, a Council of Ministers for the member states, a Commission as the executive, and a Court of Justice to interpret the law.
Caspar Bartholin (whom Bartholin's glands are named after), a 17th-century Danish anatomist, dismissed Colombo's and Falloppio's claims that they discovered the clitoris, arguing that the clitoris had been widely known to medical science since the second century. Although 17th-century midwives recommended to men and women that women should aspire to achieve orgasms to help them get pregnant for general health and well-being and to keep their relationships healthy, debate about the importance of the clitoris persisted, notably in the work of Regnier de Graaf in the 17th century and Georg Ludwig Kobelt in the 19th. Like Falloppio and Bartholin, de Graaf criticized Colombo's claim of having discovered the clitoris; his work appears to have provided the first comprehensive account of clitoral anatomy. "We are extremely surprised that some anatomists make no more mention of this part than if it did not exist at all in the universe of nature", he stated. "In every cadaver, we have so far dissected we have found it quite perceptible to sight and touch". De Graaf stressed the need to distinguish nympha from clitoris, choosing to "always give [the clitoris] the name clitoris" to avoid confusion; this resulted in the frequent use of the correct name for the organ among anatomists, but considering that nympha was also varied in its use and eventually became the term specific to the labia minora, more confusion ensued.
== Career and research == Her first position was at the Allan Memorial Institute of Psychiatry (associated with McGill University). In 1952, she joined the staff of the National Institute for Medical Research (NIMR) where she served as head of the division of Immunology from 1976 to 1988. During that time, she worked extensively with fellow immunologist John H. Humphrey to establish the immunology divisions. Askonas focused on B cells and determined their role in producing antibodies as part of the immune response. At the NIMR she began researching the biosynthesis of polypeptides in milk proteins discovering that the peptides were synthesised from amino acids rapidly in one piece. From 1955 to 1959 she studied the sites of antibody formation using radioactivity to develop our understanding of antibody molecules and the cells of the immune system. From 1959 to 1961 she studied plasma cell tumors as models for antibody formation. She went on to investigate macrophages and their role in antigen presentation (1962–1968). From 1963 to 1966 she studied the fate of antigen in relation to antibody formation and later continued her study of B cells from 1965 to 1970. She wrote several biographies of high-profile scientists, including Niels Kaj Jerne, César Milstein and John Herbert Humphrey. Askonas conducted a filmed interview with Stanley Peart as a segment of what became the Medical Sciences Video Archive housed in the special collections of the library at Oxford Brookes University.
Sources: en.wikipedia.org
The four substrates of this enzyme are eucalyptol, reduced nicotinamide adenine dinucleotide phosphate (NADPH), oxygen, and a proton. Its products are 2-exo-hydroxy-1,8-cineole, oxidised NADP+, and water. It is a cytochrome P450 protein containing heme.
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The DOx drugs act as agonists of the serotonin 5-HT2 receptors, including of the serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptors. Their psychedelic effects are thought to be mediated specifically by activation of the serotonin 5-HT2A receptor. In contrast to other amphetamines, DOx drugs like DOC, DOET, and DOM are inactive as monoamine releasing agents and reuptake inhibitors. Some of the DOx drugs, including DOB, DOET, DOI, and DOM, are agonists of the rat, rhesus monkey, and/or human trace amine-associated receptor 1 (TAAR1) with varying potencies.
Uranium, like all elements with an atomic number greater than 82, has no stable isotopes. All isotopes of uranium are radioactive because the strong nuclear force does not prevail over electromagnetic repulsion in nuclides containing more than 82 protons. Nevertheless, the two most stable isotopes, 238U and 235U, have half-lives long enough to occur in nature as primordial radionuclides, with measurable quantities having survived since the formation of the Earth. These two nuclides, along with thorium-232, are the only confirmed primordial nuclides heavier than nearly-stable bismuth-209. Natural uranium consists of three major isotopes: uranium-238 (99.28% natural abundance), uranium-235 (0.71%), and uranium-234 (0.0054%). There are also five other trace isotopes: uranium-240, a decay product of plutonium-244; uranium-239, which is formed when 238U undergoes spontaneous fission, releasing neutrons that are captured by another 238U atom; uranium-237, which is formed when 238U captures a neutron but emits two more, which then decays to neptunium-237; uranium-236, which occurs in trace quantities due to neutron capture on 235U and as a decay product of plutonium-244; and finally, uranium-233, which is formed in the decay chain of neptunium-237. Additionally, uranium-232 would be produced by the double beta decay of natural thorium-232, though this energetically possible process has never been observed. Uranium-238 is the most stable isotope of uranium, with a half-life of about 4.463×109 years, roughly the age of the Earth.
=== Electrogenetics === Mammalian designer cells are engineered by humans to behave a specific way, such as an immune cell that expresses a synthetic receptor designed to combat a specific disease. Electrogenetics is an application of synthetic biology that involves utilizing electrical fields to stimulate a response in engineered cells. Controlling the designer cells can be done with relative ease through the use of common electronic devices, such as smartphones. Additionally, electrogenetics allows for the possibility of creating devices that are much smaller and compact than devices that use other stimulus through the use of microscopic electrodes. One example of how electrogenetics is used to benefit public health is through stimulating designer cells that are able to produce/deliver therapeutics. This was implemented in ElectroHEK cells, cells that contain voltage-gated calcium channels that are electrosensitive, meaning that the ion channel can be controlled by electrical conduction between electrodes and the ElectroHEK cells. The expression levels of the artificial gene that these ElectroHEK cells contained was shown to be able to be controlled by changing the voltage or electrical pulse length. Further studies have expanded on this robust system, one of which is a beta cell line system designed to control the release of insulin based on electric signals.
Sources: en.wikipedia.org
=== Biochemical production === Succinic acid is an important biobased chemical utilized for the production of biodegradable polymers including polybutylene succinate (PBS) and as feedstock to other biobased chemicals like 1,4-butanediol. Succinic acid can be produced via the fermentation of sugar and carbon dioxide using native strains of bacteria; however, yields depend upon strain and conditions. Neutral or acidic fermentations are feasible, with low-pH fermentations facilitated by acid-resistant yeast strains simplifying downstream recovery through avoiding neutralization and reacidification. Throughout the 2010s, several companies ordered commercial-scale production facilities, e.g., BioAmber, Myriant, Reverdia, and Succinity, on different host organisms and feedstocks like corn syrup and sorghum starch. While having proven the technical feasibility of succinic acid large-scale biobased production, most of them failed to compete economically with petrochemical products on a commercial scale. Several of the plants were spun off or shut down to new proprietors, demonstrating the financial challenges of scaling up bio-based platforms within current markets. However, these projects are evidence that under right market conditions, succinic acid biobased has promise for greater industrial use.
reactant(s) ⇌ product(s) The sign ⇌ means "are in equilibrium with". This definition refers to macroscopic properties. Changes do occur at the microscopic level of atoms and molecules, but to such a minute extent that they are not measurable and in a balanced way so that the macroscopic quantities do not change. Chemical equilibrium is a dynamic state in which forward and backward reactions proceed at such rates that the macroscopic composition of the mixture is constant. Thus, equilibrium sign ⇌ symbolizes the fact that reactions occur in both forward
Camouflage does not always fool a predator. When caught out, snake species adopt different defensive tactics and use a complicated set of behaviors when attacked. Some species, like cobras or hognose snakes, first elevate their head and spread out the skin of their neck in an effort to look large and threatening. Failure of this strategy may lead to other measures practiced particularly by cobras, vipers, and closely related species, which use venom to attack. The venom is modified saliva, delivered through fangs from a venom gland. Some non-venomous snakes, such as American hognose snakes or European grass snake, play dead when in danger; some, including the grass snake, exude a foul-smelling liquid to deter attackers.
== History == Dutasteride was patented in 1996 and was first described in the scientific literature in 1997. It was approved by the FDA for the treatment of BPH in November 2001, and was introduced on the United States market the following year under the brand name Avodart. Dutasteride has subsequently been introduced throughout the world. The patent protection of dutasteride expired in November 2015, so the drug has since become available in the United States in a variety of low-cost generic formulations. It was approved for the treatment of scalp hair loss in South Korea in 2009, in Japan in 2015 and in Taiwan in 2016. It has not been approved for this indication in the United States, though it is often used off-label both orally and topically.
Sources: en.wikipedia.org
The solid is kept cold, dry and dark, typically at minus twenty degrees Celsius, in a sealed container with desiccant. Dissolved material is kept refrigerated and used promptly. Freezing and thawing a solution repeatedly is avoided because it accelerates degradation.
Reversed-phase chromatography with ultraviolet detection gives a purity percentage, while mass spectrometry confirms identity. Amino acid analysis checks the residue composition. Buyers typically request a certificate of analysis showing these measurements for the specific lot.
It is not authorised as a medicine in the United States or the European Union. Material is sold there as a research chemical or cosmetic ingredient. Some related short peptides are registered drugs in Russia, which is a distinct national situation rather than a general approval.
It is a synthetic tetrapeptide built from alanine, glutamate, aspartate and glycine. The four residues are joined by standard peptide bonds, giving a linear chain rather than a branched structure.