epitalon raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-02-02. Anything still debated is marked as such rather than presented as settled.
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 proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
Interest in epitalon is usually discussed within the broader field of short peptide bioregulators, a category that includes other synthetic di-, tri-, and tetrapeptides studied by the same research group. These compounds share a common rationale: that small fragments of tissue-derived proteins can retain biological activity and can be produced reproducibly. The category as a whole remains outside mainstream pharmacological consensus, and epitalon specifically has a limited presence in independent, non-Russian research literature, which shapes how its evidence base is described.
Epitalon is a synthetic tetrapeptide with the amino acid sequence alanine-glutamate-aspartate-glycine, abbreviated Ala-Glu-Asp-Gly or AEDG. It was developed by the Russian researcher Vladimir Khavinson and colleagues during work on peptide bioregulators derived from the pineal gland. The compound is short enough to be produced by standard solid-phase peptide synthesis and is typically handled as a lyophilized white powder. Its small size distinguishes it from larger pineal peptides such as epithalamin, a complex extract from which the tetrapeptide was conceptually derived.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four amino acid residues |
| Residue sequence | Ala-Glu-Asp-Gly | Abbreviated AEDG |
| Approximate mass | 390.35 Da | Monoisotopic, free base form |
| Parent preparation | Epithalamin extract | Derived from pineal tissue |
| Common spelling variants | Epithalon, epithalone, AEDG | Affects literature retrieval |
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
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.
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.
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.
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.
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.
== Early life and education == Born in Aarberg, Switzerland, Wüthrich was educated in chemistry, physics, and mathematics at the University of Bern before pursuing his PhD supervised by Silvio Fallab at the University of Basel, awarded in 1964.
Pyrrole-2-carboxylate monooxygenase (EC 1.14.13.130, pyrrole-2-carboxylate oxygenase) is an enzyme with systematic name pyrrole-2-carboxylate,NADH:oxygen oxidoreductase (5-hydroxylating). This enzyme catalyses the following chemical reaction
Type I – originates in ascending aorta, and propagates at least to the aortic arch and often beyond it distally. It is most often seen in patients less than 65 years of age and is the most lethal form of the disease. Type II – originates in the ascending aorta and is confined to it. Type III – originates in the descending aorta and rarely extends proximally, but will extend distally. It most often occurs in elderly patients with atherosclerosis and hypertension.
=== Maturation of the electrical properties of the action potential === A neuron's ability to generate and propagate an action potential changes during development. How much the membrane potential of a neuron changes as the result of a current impulse is a function of the membrane input resistance. As a cell grows, more channels are added to the membrane, causing a decrease in input resistance. A mature neuron also undergoes shorter changes in membrane potential in response to synaptic currents. Neurons from a ferret lateral geniculate nucleus have a longer time constant and larger voltage deflection at P0 than they do at P30. One consequence of the decreasing action potential duration is that the fidelity of the signal can be preserved in response to high frequency stimulation. Immature neurons are more prone to synaptic depression than potentiation after high frequency stimulation. In the early development of many organisms, the action potential is actually initially carried by calcium current rather than sodium current. The opening and closing kinetics of calcium channels during development are slower than those of the voltage-gated sodium channels that will carry the action potential in the mature neurons. The longer opening times for the calcium channels can lead to action potentials that are considerably slower than those of mature neurons. Xenopus neurons initially have action potentials that take 60–90 ms. During development, this time decreases to 1 ms. There are two reasons for this drastic decrease.
Sources: en.wikipedia.org
This process is similar to angiogenesis but involves the creation of lymphatic vessels which are essential for draining excess fluid and fighting infections. This process is also key to conditions like inflammation and the spreading of cancer.
Evaporation and sublimation into a vacuum is called outgassing. All materials, solid or liquid, have a small vapour pressure, and their outgassing becomes important when the vacuum pressure falls below this vapour pressure. Outgassing has the same effect as a leak and will limit the achievable vacuum. Outgassing products may condense on nearby colder surfaces, which can be troublesome if they obscure optical instruments or react with other materials. This is of great concern to space missions, where an obscured telescope or solar cell can ruin an expensive mission. The most prevalent outgassing product in vacuum systems is water absorbed by chamber materials. It can be reduced by desiccating or baking the chamber, and removing absorbent materials. Outgassed water can condense in the oil of rotary vane pumps and reduce their net speed drastically if gas ballasting is not used. High vacuum systems must be clean and free of organic matter to minimize outgassing. Ultra-high vacuum systems are usually baked, preferably under vacuum, to temporarily raise the vapour pressure of all outgassing materials and boil them off. Once the bulk of the outgassing materials are boiled off and evacuated, the system may be cooled to lower vapour pressures and minimize residual outgassing during actual operation. Some systems are cooled well below room temperature by liquid nitrogen to shut down residual outgassing and simultaneously cryopump the system.
Home Secretary Suella Braverman says she is seeking "urgent advice" on potentially banning the American Bully XL dog breed following an attack by a dog on an 11-year-old girl in Birmingham. 12 September Pepco Group, owners of Poundland, announce they will take on the lease of 71 Wilko stores and convert them into Poundland outlets. Government data reveals that average wages increased by 7.8% from May to July, matching the pace of inflation for the first time since 2021. A joint study carried out by the University of Exeter, the University of Surrey and the Working Party on Sexual Misconduct in Surgery highlights the experiences of female surgeons, many of whom say they have faced sexual harassment, sexual assault or been raped by male colleagues. Stonegate Group, the UK's largest pub chain, announces plans to introduce dynamic pricing during evenings and weekends at around 800 of its 4,000 outlets. 13 September Data from the Office for National Statistics indicates the UK economy shrank by 0.5% during July, which is largely attributed to strike action and wet weather. Data published by UK Finance shows payments by cash in the UK rose during 2022 for the first time in ten years, but were still lower than those by debit and credit card. 15 September Following a recent spate of dog attacks, primarily involving the American XL bully, the government announces that the breed will be banned under the Dangerous Dogs Act by the end of the year.
This is a promising and newer microarray application for the diagnosis, study and treatment of complex diseases such as cancer. The technology merges laser capture microdissection (LCM) with micro array technology, to produce reverse-phase protein microarrays. In this type of microarrays, the whole collection of protein themselves are immobilized with the intent of capturing various stages of disease within an individual patient. When used with LCM, reverse phase arrays can monitor the fluctuating state of proteome among different cell population within a small area of human tissue. This is useful for profiling the status of cellular signaling molecules, among a cross-section of tissue that includes both normal and cancerous cells. This approach is useful in monitoring the status of key factors in normal prostate epithelium and invasive prostate cancer tissues. LCM then dissects these tissue and protein lysates were arrayed onto nitrocellulose slides, which were probed with specific antibodies. This method can track all kinds of molecular events and can compare diseased and healthy tissues within the same patient enabling the development of treatment strategies and diagnosis. The ability to acquire proteomics snapshots of neighboring cell populations, using reverse-phase microarrays in conjunction with LCM has a number of applications beyond the study of tumors. The approach can provide insights into normal physiology and pathology of all the tissues and is invaluable for characterizing developmental processes and anomalies.
=== Radiation protection register === According to § 170 StrlSchG [Radiation Protection Act] (in German) all occupationally exposed persons and holders of radiation passports require a radiation protection register number (SSR number or SSRN), a unique personal identification number, as of December 31, 2018. The SSR number facilitates and improves the allocation and balancing of individual dose values from occupational radiation exposure in the radiation protection register. It replaces the former radiation passport number. It is used to monitor dose limits. Companies are obliged to deploy their employees in such a way that the radiation dose to which they are exposed does not exceed the limit of 20 millisieverts per calendar year. In Germany, about 440,000 people were classified as occupationally exposed to radiation in 2016. According to § 145 StrlSchG [German Radiation Protection Act] (in German) paragraph 1, Sentence 1, "in the case of remediation and other measures to prevent and reduce exposure at radioactively contaminated sites, the person who carries out the measures himself or has them carried out by workers under his supervision must carry out an assessment of the body dose of the workers before starting the measures". Applications for SSR numbers must be submitted to the Federal Office for Radiation Protection (BfS) by March 31, 2019 for all employees currently under surveillance.
Sources: en.wikipedia.org
==== NOD-like receptors ==== Probably the most well-known receptors of peptidoglycan are the NOD-like receptors (NLRs), mainly NOD1 and NOD2. The NOD1 receptor is activated after iE-DAP (γ-d-glutamyl-meso-diaminopimelic acid) binding, while NOD2 recognizes MDP (muramyl dipeptide), by their LRR domains. Activation leads to self-oligomerization, resulting in activation of two signalling cascades. One triggers activation of NF-κB (through RIP2, TAK1 and IKK), second leads to MAPK signalling cascade. Activation of these pathways induces production of inflammatory cytokines and chemokines. NOD1 is expressed by diverse cell types, including myeloid phagocytes, epithelial cells and neurons. NOD2 is expressed in monocytes and macrophages, epithelial intestinal cells, Paneth cells, dendritic cells, osteoblasts, keratinocytes and other epithelial cell types. As cytosolic sensors, NOD1 and NOD2 must either detect bacteria that enter the cytosol, or peptidoglycan must be degraded to generate fragments that must be transported into the cytosol for these sensors to function. Recently, it was demonstrated that NLRP3 is activated by peptidoglycan, through a mechanism that is independent of NOD1 and NOD2. In macrophages, N-acetylglucosamine generated by peptidoglycan degradation was found to inhibit hexokinase activity and induce its release from the mitochondrial membrane. It promotes NLRP3 inflammasome activation through a mechanism triggered by increased mitochondrial membrane permeability. NLRP1 is also considered as a cytoplasmic sensor of peptidoglycan.
Autofluorescence is the natural fluorescence of biological structures (autofluorophores) such as mitochondria and lysosomes, in contrast to fluorescence originating from artificially added fluorescent markers (fluorophores). The most commonly observed autofluorescencing molecules are NADPH and flavins; the extracellular matrix can also contribute to autofluorescence because of the intrinsic properties of collagen and elastin. Generally, proteins containing an increased amount of the amino acids tryptophan, tyrosine, and phenylalanine show some degree of autofluorescence. Autofluorescence also occurs in non-biological materials found in many papers and textiles. Autofluorescence from U.S. paper money has been demonstrated as a means for discerning counterfeit currency from authentic currency.
Intraocular pressure can sometimes reach 80 mmHg (11 kPa). It characteristically manifests as ciliary body inflammation and massive trabecular edema that sometimes extends to Schlemm's canal. This condition is differentiated from malignant glaucoma by the presence of a deep and clear anterior chamber and a lack of aqueous misdirection. Also, the corneal appearance is not as hazy. A reduction in visual acuity can occur, followed by neuroretinal breakdown.
==== Spinal ==== Spinal fusion can be performed either as a preventative measure or to correct existing scoliosis, although the inherent fragility of OI bone makes this operation more complex in OI patients than it does with patients who have adolescent idiopathic scoliosis, but normal bone density. Despite the risks, however, three Nemours–duPont orthopedic surgeons who specialize in surgical intervention for osteogenesis imperfecta recommend operating if the curve is greater than 50° after a child is past peak height velocity, as the spine's curve can continue to worsen even into adulthood. Due to the risk involved, the same surgeons recommend that surgery for basilar impressions and basilar invaginations should only be carried out if the pressure being exerted on the spinal cord and brain stem is causing actual neurological symptoms. Once basilar invagination has become symptomatic, only surgery can halt or reverse the progression of neurological deficits.
=== DNA === There are some oligonucleotide sequences, called triplet-forming oligonucleotides (TFOs) that can bind to form a triplex with a longer molecule of double-stranded DNA; TFOs can inactivate a gene or help to induce mutations. TFOs can only bind to certain sites in a larger molecule, so researchers must first determine whether a TFO can bind to the gene of interest. Twisted intercalating nucleic acid is sometimes used to improve this process. Mapping of genome-wide TFO-TTS pairs by sequencing is a useful way to study the triplex forming DNA in the whole genome using oligo-library.
Sources: en.wikipedia.org
It is based on epithalamin, a peptide-rich preparation obtained from pineal gland tissue and studied in the former Soviet Union. Researchers later identified the tetrapeptide AEDG as a constituent fragment of that material. Modern supplies are produced by chemical synthesis rather than tissue extraction.
No. Epithalamin is a heterogeneous extract containing many peptides, while epitalon is a single synthesised tetrapeptide. Publications sometimes treat findings from the two as equivalent, which is a common source of confusion. Their compositions differ and they are not interchangeable in analytical terms.
Most published work uses cell cultures or rodents because those models are faster and less costly to run. The few human trials that have been reported are small, and several lack control groups or blinding. This restricts what can reasonably be concluded about effects in people.
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.