epithalamin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-08-09. Anything still debated is marked as such rather than presented as settled.
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.
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 published literature is dominated by a small number of research groups, much of it in Russian-language journals, and independent replication outside those groups is limited. Studies are typically small, use cultured cells or rodent models, and report endpoints that differ between papers, which makes comparison difficult. Large randomised human trials have not appeared in the indexed literature. Questions about absorption, distribution and clearance are therefore still treated as open in reviews that mention the compound.
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
Proposed mechanisms centre on cell-culture observations rather than a defined receptor interaction. Several reports describe increased expression of the telomerase catalytic subunit after exposure of cultured human cells, and the authors attributed the effect to short peptide fragments entering the nucleus and influencing gene transcription. No receptor for the tetrapeptide has been identified, and the free peptide is expected to be degraded rapidly by plasma peptidases. Whether any measurable fraction reaches intact tissues after administration remains an unresolved question rather than an established finding.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Linear tetrapeptide, also written AEDG |
| Molecular mass | About 390.35 g/mol | Value calculated from the sequence |
| Appearance | White to off-white powder | Lyophilised material forms a loose cake |
| Solubility | Freely soluble in water | Also dissolves in isotonic saline |
| Storage | -20 °C, desiccated | Aliquot solutions to avoid freeze–thaw cycling |
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.
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 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.
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Literature searches for this compound must account for several spelling variants. Indexing databases contain epitalon, epithalon, epithalone, and AEDG, and relevant records are scattered across Russian-language and English-language journals that do not consistently cross-cite. Early publications describe the parent extract as a mixture of many peptides, whereas later work addresses the single synthetic tetrapeptide. That shift in nomenclature complicates comparison between studies, because extract data and tetrapeptide data are sometimes cited interchangeably. A search strategy omitting the alternate spellings will return an incomplete set of references.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
=== Therapeutic foods === Due in part to limited research on supplementary feeding, there is little evidence that this strategy is beneficial. A 2015 systematic review of 32 studies found that there are limited benefits when children under 5 receive supplementary feeding, especially among younger, poorer, and more undernourished children. However, specially formulated foods do appear to be useful in treating moderate acute malnutrition in the developing world. These foods may have additional benefits in humanitarian emergencies, since they can be stored for years, can be eaten directly from the packet, and do not have to be mixed with clean water or refrigerated. In young children with severe acute malnutrition, it is unclear if ready-to-use therapeutic food differs from a normal diet. Severely malnourished individuals can experience refeeding syndrome if fed too quickly. Refeeding syndrome can result regardless of whether food is taken orally, enterally or parenterally. It can present several days after eating with potentially fatal heart failure, dysrhythmias, and confusion. Some manufacturers have fortified everyday foods with micronutrients before selling them to consumers. For example, flour has been fortified with iron, zinc, folic acid, and other B vitamins like thiamine, riboflavin, niacin and vitamin B12. Baladi bread (Egyptian flatbread) is made with fortified wheat flour. Other fortified products include fish sauce in Vietnam and iodized salt.
== Genome and genetics == H. influenzae was the first free-living organism to have its entire genome sequenced. The sequencing was completed in 1995 by Craig Venter and his team at the Institute for Genomic Research, now part of the J. Craig Venter Institute. Haemophilus was chosen because one of the project leaders, Nobel laureate Hamilton Smith, had been working on it for decades and was able to provide high-quality DNA libraries. The sequencing method used was whole-genome shotgun, which was completed and published in Science in 1995. The genome of strain Rd KW20 consists of 1,830,138 base pairs of DNA in a single circular chromosome that contains 1604 protein-coding genes, 117 pseudogenes, 57 tRNA genes, and 23 other RNA genes. About 90% of the genes have homologs in E. coli, another gamma-proteobacterium. In fact, the similarity between genes of the two species ranges from 18% to 98% protein sequence identity, with the majority sharing 40–80% of their amino acids (with an average of 59%). Conjugative plasmids (DNA molecules that are capable of horizontal transfer between different species of bacteria) can frequently be found in H. influenzae. It is common that the F+ plasmid of a competent Escherichia coli bacterium conjugates into the H. influenzae bacterium, which then allows the plasmid to transfer among H. influenzae strands via conjugation.
Open aortic surgery with replacement of the damaged section of the aorta with a tube graft (often made of Dacron) when no damage to the aortic valve is seen Bentall procedure – replacement of the damaged section of the aorta and replacement of the aortic valve David procedure – replacement of the damaged section of the aorta and reimplantation of the aortic valve Thoracic endovascular aortic repair, a minimally invasive surgical procedure usually combined with ongoing medical management Frozen elephant trunk procedure (FET) is one-stage procedure for the repair of acute aortic dissection that permits concurrent total aortic arch replacement with antegrade delivery of a descending aortic stent-graft which itself functions as a proximal landing zone to facilitate prospective endovascular intervention (TEVAR) to treat residual or de novo disease in the more distal aorta. A number of comorbid conditions increase the surgical risk of repair of an aortic dissection. These conditions include the following:
=== Initiation === Before considering the propagation of action potentials along axons and their termination at the synaptic knobs, it is helpful to consider the methods by which action potentials can be initiated at the axon hillock. The basic requirement is that the membrane voltage at the hillock be raised above the threshold for firing. There are several ways in which this depolarization can occur.
At the 19th Party Congress, Xi stated, "We will fully implement the Party's basic policy on religious affairs, uphold the principle that religions in China must be Chinese in orientation and provide active guidance to religions so that they can adapt themselves to a socialist society."
Sources: en.wikipedia.org
This method allows identification of poisons at a few parts per billion, but that may be insufficient for reliable detection of the isotopic signature of the adducts, and therefore an unambiguous identification of the geographic origin of the poison.
Aldosterone is a mineralocorticoid which is synthesized in the adrenal glands. When aldosterone is secreted from the adrenal glands, it binds to the mineralocorticoid receptor in the renal tubule cell and forms a complex. This complex enhances transcription of specific DNA segments in the nucleus, leading to the formation of two protein transporters, Na+/K+ ATPase pump at the basolateral membrane and Na+ channel called ENaC, located at the apical membrane of the renal tubule cell. These protein transporters increase sodium reabsorption and potassium excretion in the distal tubule and the collecting duct of the kidneys. This helps the body to maintain normal volume and electrolyte balance, increasing the blood pressure. Mineralocorticoid receptor antagonists decrease the aldosterone effect by binding to the mineralocorticoid receptor inhibiting aldosterone. This leads to higher levels of potassium in serum and increased sodium excretion, resulting in decreased body fluid and lower blood pressure.
=== June === 1 June – Robert Anderson, cricketer (Otago, Central Districts, national team) (born 1948). 4 June Edwin Perry, politician, New Zealand First list MP (2002–2005), Masterton District Councillor (2007–2010) (born 1948). Bruce Stewart, lawyer, Rhodes Scholar (1975), King's Counsel (since 2000) (born 1953). 6 June – Marise Wipani, beauty pageant contestant, actor (Came a Hot Friday, Shortland Street, Soldier Soldier), and television presenter (Lotto) (born 1964). 7 June – David Lean, local politician, Mayor of New Plymouth (1980–1992), Taranaki Regional Councillor (since 1989) (born 1948). 8 June Anthony Reid, historian (Australian National University, UCLA, National University of Singapore) (born 1939). Stu Wilson, rugby union player (Wellington, national team) and television commentator (born 1954). 10 June – Roka Ngarimu-Cameron, tohunga raranga and traditional Māori arts academic (University of Otago) (born 1948). 12 June Maurice Gee, novelist (Under the Mountain, In My Father's Den, Plumb), Arts Foundation of New Zealand Icon (since 2003) (born 1931). Phil Silva, psychologist and paediatrician (University of Otago), founder (1972) and director (1972–1999) of the Dunedin Study (born 1940). Sir Cliff Skeggs, Hall of Fame businessman and local politician, Mayor of Dunedin (1977–1989) (born 1931). 14 June – Lorraine Barry, music manager (Dave Dobbyn, Ice-T, Spice Girls) (born c. 1958). 15 June – Barry Vercoe, computer scientist (Massachusetts Institute of Technology) and composer, inventor of Csound (1985) (born 1937).
In April 1921, using the "well-equipped, funded laboratory" of John Macleod at the Physiology Department of the University of Toronto, Frederick Banting and Charles Best began investigating processes through which "the active principle of the extracts of degenerated [bovine] pancreas" could potentially be preserved without being destroyed (as was the case with the (then) current extraction processes).
Sources: en.wikipedia.org
=== Peripheral edema and hypoalbuminemia === Kwashiorkor is a form of protein deficiency, which can result in both osmotic imbalances and irregularities in the lymphatic system. Kwashiorkor is most notable for peripheral edema. The presence of edema in kwashiorkor is correlated with very low albumin concentration (hypoalbuminemia). Edema results from a loss of fluid balance between the hydrostatic and oncotic pressures across the capillary blood vessel walls due to the lack of protein which affects the body's ability to draw fluid from the tissues into the bloodstream. Low albumin concentration influences negatively the strength of oncotic pressure. Failure leads to fluid buildup in the abdomen, resulting in edema and belly distension. Furthermore, the release of antidiuretic hormone is stimulated by hypovolemia, also leading to the development of peripheral edema. Plasma renin is also stimulated, promoting sodium retention. It is important to distinguish the pathophysiology of marasmus and kwashiorkor when it comes to treating malnourished children who may have hypovolemic shock that is caused by an acute loss of salt and water. Children with severe albumin deficiency struggle physiologically to maintain their blood volume.
Many people with MCT8 deficiency experience a range of debilitating effects, including the inability to walk or sit independently, absent or severely limited speech, intellectual disability, feeding difficulties and chronic stress on the heart and metabolism.
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Sources: en.wikipedia.org
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.
AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.
Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.
No. Epithalamin is a heterogeneous peptide fraction obtained from pineal gland extract and contains many components. Epitalon is a single synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly. Researchers synthesised the shorter peptide while attempting to identify active sequences within the extract.