The short version of Epithalamin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-05-22. Anything still debated is marked as such rather than presented as settled.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. It was designed at the St. Petersburg Institute of Bioregulation and Gerontology as a short, chemically defined analogue of epithalamin, a fraction obtained from bovine pineal tissue. Small peptide bioregulators of this type formed a long-running line of work there from the 1980s onward. Because the molecule is produced by solid-phase synthesis rather than extraction, its composition is exact and its purity can be measured directly.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Calculated from the four residues with three water losses |
| Molecular mass | About 390.35 g/mol | Monoisotopic mass near 390.14, used for mass-spectrometric identification |
| Peptide sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG; no disulfide bonds or modified residues |
| Appearance | White to off-white solid | Supplied as a dried powder |
| Isoelectric point | Around 4 | Estimated from aspartate and glutamate side-chain pKa values |
Published work on this compound consists mainly of in vitro experiments, animal studies, and small clinical investigations, a substantial share of which appeared in Russian-language journals. Sample sizes are generally small, control conditions differ between studies, and several endpoints rely on markers whose clinical meaning is itself debated. Reviews of the longevity field treat the peptide as an early example of telomerase-directed research rather than an established intervention. Regulatory treatment varies by country: some jurisdictions place it under prescription controls, others treat it as a laboratory material, and importation may be restricted regardless of local status.
Epitalon is a synthetic tetrapeptide whose sequence is alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. It was developed in Russia during the 1980s and 1990s by investigators associated with the St. Petersburg Institute of Bioregulation and Gerontology, who studied short peptides as regulators of gene expression and tissue function. The alternative spelling epithalon appears interchangeably in the literature, and the two names refer to the same molecule. Outside Russia it is encountered chiefly as a research chemical rather than a licensed medicine, and it holds no approval from the United States Food and Drug Administration or the European Medicines Agency.
The peptide is a synthetic analogue of epithalamin, a preparation extracted from bovine pineal glands. Investigators sought a short, chemically defined molecule that would reproduce some of the endocrine and gerontological observations attributed to the glandular extract. Proposed mechanisms centre on induction of telomerase activity, an effect reported in cultured human somatic cells in the early 2000s, together with influences on melatonin secretion and neuroendocrine regulation. Those mechanisms remain incompletely characterised, and the reported telomerase response has not been consistently reproduced by independent groups working in comparable systems.
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.
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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
The SO interaction causes the binding energy of nihonium monohydride to be reduced by about 1 eV and the nihonium–hydrogen bond length to decrease as the bonding 7p1/2 orbital is relativistically contracted. This is unique among the 7p element monohydrides; all the others have relativistic expansion of the bond length instead of contraction. Another effect of the SO interaction is that the Nh–H bond is expected to have significant pi bonding character (side-on orbital overlap), unlike the almost pure sigma bonding (head-on orbital overlap) in thallium monohydride (TlH). The analogous monofluoride (NhF) should also exist. Nihonium(I) is predicted to be more similar to silver(I) than thallium(I): the Nh+ ion is expected to more willingly bind anions, so that NhCl should be quite soluble in excess hydrochloric acid or ammonia; TlCl is not. In contrast to Tl+, which forms the strongly basic hydroxide (TlOH) in solution, the Nh+ cation should instead hydrolyse all the way to the amphoteric oxide Nh2O, which would be soluble in aqueous ammonia and weakly soluble in water. The adsorption behaviour of nihonium on gold surfaces in thermochromatographical experiments is expected to be closer to that of astatine than that of thallium. The destabilisation of the 7p3/2 subshell effectively leads to a valence shell closing at the 7s2 7p2 configuration rather than the expected 7s2 7p6 configuration with its stable octet. As such, nihonium, like astatine, can be considered to be one p-electron short of a closed valence shell.
=== Putsch === The term putsch ([pʊtʃ], from Swiss German for 'knock') denotes the political-military actions of a minority reactionary coup. The term was initially coined for the Züriputsch of 6 September 1839 in Switzerland. It was also used for attempted coups in Weimar Germany, such as the 1920 Kapp Putsch, Küstrin Putsch, and Adolf Hitler's 1923 Beer Hall Putsch. The 1934 Night of the Long Knives was Hitler's purge to eliminate opponents, particularly the paramilitary faction led by Ernst Röhm, but Nazi propaganda justified it as preventing a supposed putsch planned or attempted by Röhm. The Nazi term Röhm-Putsch is still used by Germans to describe the event, often with quotation marks as the 'so-called Röhm Putsch'. The 1961 Algiers putsch and the 1991 August Putsch also use the term. The 2023 Wagner Group rebellion has also been described as a putsch.
However, it is described as a "clear-headed candyflip", with entactogenic-like effects, LSD-like effects such as visuals, but a very clear head space. In addition, it is said to not have the same kind of forceful positive mood push that MDMA has, and to be a little more unpredictable and capable of causing bad trips or negative head spaces. 2C-B is said to be more of a "party drug", to be more recreational drug, and to have less likelihood of challenging, emotional-breakthrough, or mystical-type experiences, relative to psychedelics like psilocybin and LSD. Formal clinical studies have found that 2C-B produces a mixture of psychedelic, some possible entactogen-like, and some stimulant effects. Specific effects in these studies have included slight hallucinogenic states, perceptual changes, ego dissolution, time dilation, increased creativity, stimulation, vigor, happiness or elation, euphoria, feelings of well-being, reduced anger, enhanced sociability and friendliness, increased reactivity to negative emotional stimuli, decreased ability to recognize expressions of happiness, augmented emotionality in speech, tenseness, confusion, and mild sympathomimetic effects such as pressor effects, among others. Findings on the entactogen-like effects of 2C-B have been mixed, with some studies reporting that it produces such effects but other studies finding no such effects similarly to psilocybin. However, in other research, both psilocybin and MDMA have been found to increase emotional empathy.
=== Marketed === Daridorexant (nemorexant; Quviviq) – dual OX1 and OX2 antagonist – approved for insomnia in January 2022, formerly under development for sleep apnea – half-life 8 hours Fazamorexant (Mengping) – dual OX1 and OX2 antagonist – approved for insomnia in China in May 2026 – half-life 2–4 hours Lemborexant (Dayvigo) – dual OX1 and OX2 antagonist – approved for insomnia in December 2019 and released June 1 2020, under development for circadian rhythm sleep disorders, chronic obstructive pulmonary disease, and sleep apnea – half-life 17–55 hours Suvorexant (Belsomra) – dual OX1 and OX2 antagonist – approved for insomnia in August 2014, under development for delirium – half-life 12 hours Vornorexant (Vorzzz) – dual OX1 and OX2 antagonist – approved for insomnia in Japan in August 2025 – half-life 1.5–3 hours
Sources: en.wikipedia.org
Melitta Schmideberg-Klein (née Klein; 17 January 1904 – 10 February 1983), author of numerous books, academic papers and monographs; physician, psychiatrist, and psychoanalyst; daughter of leading psychoanalyst Melanie Klein; associate member of British Psychoanalytical Society and underwent analysis with Edward Glover, Hanna Segal (1918–2011), psychoanalyst of Polish Jewish descent; follower of Melanie Klein; president of British Psychoanalytical Society, vice-president of International Psychoanalytical Association; was appointed to the Freud Memorial Chair at University College, London (UCL); considered the doyen of "classical" Kleinian thinking and technique" and "one of the most distinguished psychological theorists of our time " Judah Segal, FBA (21 June 1912 – 23 October 2003, prolific author, scholar and academic; Professor of Semitic Languages at the School of Oriental and African Studies.His father was Professor Moshe Zvi Segal, Israeli rabbi, linguist and Talmudic scholar; his brother was Labour Party politician Samuel Segal; father of University of London scholar, Professor Naomi Segal. Lynne Segal (born 29 March 1944) socialist feminist academic and activist; author of over ten books and numerous scholarly monographs on ideology and geopolitics; Professor of Psychology and Gender Studies at Birkbeck, University of London, where she now works in The School of Psychosocial Studies.
The Canadian Society of Clinical Chemists (CSCC) is a nonprofit scientific society that represents clinical chemists (also known as clinical biochemists) in Canada. The organization aims to advance the practice of clinical chemistry in Canada through the promotion of importance in education, research, and practice, working at the international, national, provincial, and local levels. The CSCC is a full member of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), which is associated with the International Union of Pure and Applied Chemistry (IUPAC).
=== Pharmacodynamics === Tiagabine acts a selective GABA transporter 1 (GAT-1) blocker and hence as a GABA reuptake inhibitor (GRI). The GAT-1 is one of at least four distinct GABA transporters (GATs), with the GAT-1 being the predominant subtype in the brain, accounting for 85% of GATs in this part of the body, and thought to be responsible for most γ-aminobutyric acid (GABA) reuptake in synapses. The drug has more than 1,000-fold selectivity for the GAT-1 over the GABA transporter 2 (GAT-2), GABA transporter 3 (GAT-3), and betaine/GABA transporter (BGT-1; GAT-4). It also shows no significant affinity for GABA receptors or numerous other targets. In addition, it does not affect key cardiac ion channels. Through GAT-1 blockade, tiagabine increases levels of GABA, the major inhibitory neurotransmitter in the central nervous system, and consequently increases GABA receptor activation and GABAergic signaling, including of both GABAA and GABAB receptors. The drug has been found to increase GABAergic signaling in the hippocampus, globus pallidus, ventral pallidum, and substantia nigra in animals. It produces anticonvulsant, neuroprotective, hypnotic, analgesic, and anxiolytic-like effects in animals. In rodent drug discrimination tests, tiagabine partially substituted for muscimol and diazepam but did not substitute for gaboxadol, phenobarbitol, or zolpidem. When tiagabine was used as the training drug however, gaboxadol near-fully substituted for tiagabine. Similarly, indiplon partially substituted for tiagabine.
=== Solubility === The log P value of hydrocortisone is 1.61, which was derived from experiments done by pharmacologist Corwin Hansch and his research team. In addition, the predicted water solubility of hydrocortisone is 0.199 mg/mL. These values indicate that hydrocortisone has a low solubility in water and is more soluble in organic solvents. For other chemical information of topical hydrocortisone, please refer to the 'Topical hydrocortisone' table.
Critical response to Ellipse was generally positive. At Metacritic, which assigns a normalized rating out of 100 to reviews from mainstream critics, the album received an average score of 68, based on 12 reviews. It also earned her a further two Grammy Nominations on 2 December for Best Pop Instrumental Performance for "The Fire" and Best Engineered Non-Classical Album. On 31 January 2010, it was announced that Heap had won the latter award.
Sources: en.wikipedia.org
== See also == Aneutronic fusion Cold fusion Fusion power Neutrino astronomy Nuclear fusion Proton–proton chain, as found in stars like the Sun Stellar nucleosynthesis, the whole topic Triple-alpha process, how 12C is produced from lighter nuclei
Hood's research group corrected the neurological defect in mice (the shiverer defect) by transferring a normal MBP gene into the fertilized egg of the shiverer mouse. These discoveries led to extensive studies of MBP and its biology.
=== Dendritic secretion === Supraoptic neurons have typically 1-3 large dendrites, most of which projecting ventrally to form a mat of process at the base of the nucleus, called the ventral glial lamina. The dendrites receive most of the synaptic terminals from afferent neurons that regulate the supraoptic neurons, but neuronal dendrites are often actively involved in information processing, rather than being simply passive receivers of information. The dendrites of supraoptic neurons contain large numbers of neurosecretory vesicles that contain oxytocin and vasopressin, and they can be released from the dendrites by exocytosis. The oxytocin and vasopressin that is released at the posterior pituitary gland enters the blood, and cannot re-enter the brain because the blood–brain barrier does not allow oxytocin and vasopressin through, but the oxytocin and vasopressin that is released from dendrites acts within the brain. Oxytocin neurons themselves express oxytocin receptors, and vasopressin neurons express vasopressin receptors, so dendritically released peptides "autoregulate" the supraoptic neurons. Francoise Moos and Phillipe Richard first showed that the autoregulatory action of oxytocin is important for the milk-ejection reflex. These peptides have relatively long half-lives in the brain (about 20 minutes in the CSF), and they are released in large amounts in the supraoptic nucleus, and so they are available to diffuse through the extracellular spaces of the brain to act at distant targets.
=== Spectrum of activity === Like other third-generation cephalosporins, ceftriaxone is active against Citrobacter spp., Serratia marcescens, and beta-lactamase-producing strains of Haemophilus and Neisseria. However, unlike ceftazidime and cefoperazone, ceftriaxone does not have useful activity against Pseudomonas aeruginosa. It is generally not active against Enterobacter species, and its use should be avoided in the treatment of Enterobacter infections, even if the isolate appears susceptible, because of the emergence of resistance. Some organisms, such as Citrobacter, Providencia, and Serratia, have the ability to become resistant through the development of cephalosporinases (enzymes that hydrolyze cephalosporins and render them inactive). Although not being used as first line therapy against Staphylococcus aureus, ceftriaxone retains activity against isolates of methicillin-susceptible S. aureus and is used in clinic for infections sustained by this bacterium. In this case the dose should be doubled (e.g. 2 g intravenously every 12 hours).
Sources: en.wikipedia.org
No. Epithalamin is a peptide-containing extract of bovine pineal glands, while epitalon is a single synthetic tetrapeptide. The extract contains many peptides and other tissue components, so its composition varies between batches in ways that a synthesised sequence does not.
It is not recognised as an endogenous peptide hormone. The four-residue sequence can appear inside larger proteins and in digestive fragments of dietary protein, but no dedicated pathway producing it as a signalling molecule has been identified.
Several cell-culture reports describe increased telomerase activity after treatment, measured by enzyme assays or by transcript levels. Results differ between cell types and laboratories, and measured telomere lengthening has been reported in some studies but not in others, which leaves the physiological relevance open.
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.