This is a working overview of epithalamin, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-06-19. Anything still debated is marked as such rather than presented as settled.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Computed for the free acid of Ala-Glu-Asp-Gly |
| Molecular mass | About 390.35 g/mol | Free peptide; salt forms shift the value |
| Appearance | White to off-white solid | Typical of short peptides after freeze-drying |
| Solubility class | Freely soluble in water | Aqueous buffers are also commonly used |
| Common synonyms | Epitalon, epithalone, AEDG | AEDG is the single-letter sequence |
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 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.
Although many of the largest restaurant chains in Canada are US-based (such as McDonald's and Yum! Brands among others), some Canadian-based (owned and operated from Canada) restaurant chains are growing and have expanded into other markets, especially into the US.
==== I. Lipophilic Drugs ==== Microbubbles can facilitate the local targeting of hydrophobic drugs through the incorporation of these agents into the microbubble lipid shell. This encapsulation technique reduces systemic toxicity, increases drug localization, and improves the solubility of hydrophobic drugs. For increased localization, a targeting ligand can be appended to the exterior of the microbubble. This improves treatment efficacy. One drawback of the lipid-encapsulated microbubble as a drug delivery vehicle is its low payload efficacy. To combat this, an oil shell can be incorporated to the interior of the lipid monolayer to enhance payload efficacy.
Carpal tunnel syndrome (CTS) is the symptoms and signs characteristic of compressive median neuropathy at the carpal tunnel of the wrist. Compressive median neuropathy is a structural, largely hereditary condition that is usually measurable in both wrists. Most cases of median neuropathy at the carpal tunnel are idiopathic, meaning there is no known cause. Other causes of median nerve compression at the carpal tunnel include bleeding, swelling, and deformity associated with a wrist fracture. Carpal tunnel syndrome can also occur with rheumatoid arthritis, due to the enlarged synovial lining of the tendons causing median nerve compression. The main symptoms are numbness and tingling of the thumb, index finger, middle finger, and the thumb side of the ring finger, as well as pain in the hand and fingers. Symptoms are typically most troublesome at night. Many people sleep with their wrists bent, and the ensuing symptoms may lead to awakening. People wake less often at night if they wear a wrist splint. Untreated, and over years to decades, CTS causes loss of sensitivity, weakness, and shrinkage (atrophy) of the thenar muscles at the base of the thumb. Work-related factors such as vibration, wrist extension or flexion, hand force, and repetitive strain are risk factors for CTS. Other risk factors include being female, obesity, diabetes, rheumatoid arthritis, thyroid disease, and genetics. Diagnosis can be made with a high probability based on characteristic symptoms and signs. It can also be measured with electrodiagnostic tests.
== Further reading == Hartonen, Kari; Laitinen, Totti; Riekkola, Marja-Liisa (2011). "Current instrumentation for aerosol mass spectrometry". TrAC Trends in Analytical Chemistry. 30 (9): 1486–1496. doi:10.1016/j.trac.2011.06.007. ISSN 0165-9936.
Sources: en.wikipedia.org
Some individuals with CAIS may choose to retain their gonads. If this is the case, annual imaging of the gonads via MRI or ultrasound is recommended in order to monitor for signs of malignancy. Diagnostic laparoscopy and biopsy are also to be considered if imaging is ambiguous. A study in 2012 claimed that adult women with CAIS are increasingly likely to keep their gonads due to perceived benefits. A retrospective study which includes postpubertal CAIS individuals seen at a single UK DSD center shows that there has been a temporal shift away from gonadectomy. 76.5% CAIS individuals between 2020 and 2025 elected to retain their gonads in this study. Endogenous hormone profiles show very specific features that influence bone health, hormonal replacement therapy may improve bone mineral density, but it does not normalize it. For individuals with CAIS who wish to keep their gonads, a biannual screening program is proposed. It may be possible to avoid gonadectomy throughout the patient's life with regular imaging and routine monitoring to ensure the gonads are healthy. It is emphasized that not all imaging abnormalities are indicative of malignancy. Some activists consider that cancer risk is used to legitimate surgical and hormonal intervention because intersex bodies were positioned as inherently sick and in need of modification. Research also suggest that timely intervention to reduce genotoxicity such as DNA damage, inflammation and imbalanced autophagy may promote germ cells specification and decrease the risk of germ cells tumor.
== Metrology == A number of reference materials are available for silver nanoparticles. NIST RM 8017 contains 75 nm silver nanoparticles embedded in a cake of the polymer polyvinylpyrrolidone to stabilize them against oxidation for a long shelf life. They have reference values for mean particle size using dynamic light scattering, ultra-small-angle X-ray scattering, atomic force microscopy, and transmission electron microscopy; and size distribution reference values for the latter two methods. The BAM-N001 certified reference material contains silver nanoparticles with a specified size distribution with a number-weighted median size of 12.6 nm measured by small-angle X-ray scattering and transmission electron microscopy.
Although American rocket pioneer Robert H. Goddard developed, patented, and flew small liquid-propellant rockets as early as 1914, the United States was the only one of the three major allied World War II powers to not have its own rocket program, until Von Braun and his engineers were expatriated from Nazi Germany in 1945. The US acquired a large number of V-2 rockets and recruited von Braun and most of his engineering team in Operation Paperclip. The team was sent to the Army's White Sands Proving Ground in New Mexico, in 1945. They set about assembling the captured V-2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first photos of Earth from space, and the first two-stage rocket, the WAC Corporal-V-2 combination, in 1949. The German rocket team was moved from Fort Bliss to the Army's new Redstone Arsenal, located in Huntsville, Alabama, in 1950. From here, von Braun and his team developed the Army's first operational medium-range ballistic missile, the Redstone rocket, derivatives of which launched both America's first satellite, and the first piloted Mercury space missions. It became the basis for both the Jupiter and Saturn family of rockets.
== Other poisonous plants == Many other plants not commonly used in food or drink are also poisonous, and care should be taken to avoid accidentally contacting or ingesting them. Some of these are popular ornamental plants or are cultivated for purposes other than consumption.
=== From free energy calculation === In practice, it can be difficult to obtain statistically converged and accurate protonation free energies from titration curves if ⟨x⟩ is close to a value of 1 or 0. In this case, one can use various free energy calculation methods to obtain the protonation free energy. To obtain the free energy, one starts with a collection of states generated by some type of simulation of the residue being protonated; this can be obtained via molecular dynamics or metropolis MC (including the biased metropolis MC and many other variants). A second algorithm then looks at these states to calculate the change in free energy before and after protonation. Methods for calculating the free energy change from an ensemble of states that have been applied to pKa calculation include:
Sources: en.wikipedia.org
==== Type distribution ==== Individual muscles tend to be a mixture of various fiber types, whose proportions vary depending on the actions of that muscle. For instance, in humans, the quadriceps muscles contain ~52% type I fibers, while the soleus is ~80% type I. The orbicularis oculi muscle of the eye is only ~15% type I. Motor units within the muscle, however, have minimal variation between the fibers of that unit. It is this fact that makes the size principle of motor unit recruitment viable. The total number of skeletal muscle fibers has traditionally been thought not to change. It is believed there are no sex or age differences in fiber distribution; however, proportions of fiber types vary considerably from muscle to muscle and person to person. Among different species there is much variation in the proportions of muscle fiber types. Sedentary men and women (as well as young children) have 45% type II and 55% type I fibers. People at the higher end of any sport tend to demonstrate patterns of fiber distribution e.g. endurance athletes show a higher level of type I fibers. Sprint athletes, on the other hand, require large numbers of type IIX fibers. Middle-distance event athletes show approximately equal distribution of the two types. This is also often the case for power athletes such as throwers and jumpers. It has been suggested that various types of exercise can induce changes in the fibers of a skeletal muscle. It is thought that by performing endurance type events for a sustained period of time, some of the type IIX fibers transform into type IIA fibers.
==== Regulation in β cells ==== Glucose immediately amplifies glucokinase activity by the cooperativity effect. A second important rapid regulator of glucokinase activity in β cells occurs by direct protein-protein interaction between glucokinase and the "bifunctional enzyme" (phosphofructokinase-2/fructose-2,6-bisphosphatase), which also plays a role in the regulation of glycolysis. This physical association stabilizes glucokinase in a catalytically favorable conformation (somewhat opposite the effect of GKRP binding) that enhances its activity. In as little as 15 minutes, glucose can stimulate GCK transcription and glucokinase synthesis by way of insulin. Insulin is produced by the beta cells, but some of it acts on β cell B-type insulin receptors, providing an autocrine positive-feedback amplification of glucokinase activity. Further amplification occurs by insulin action (via A-type receptors) to stimulate its own transcription. Transcription of the GCK gene is initiated through the "upstream," or neuroendocrine, promoter. This promoter, in contrast to the liver promoter, has elements homologous to other insulin-induced gene promoters. Among the probable transacting factors are Pdx-1 and PPARγ. Pdx-1 is a homeodomain transcription factor involved in the differentiation of the pancreas. PPARγ is a nuclear receptor that responds to glitazone drugs by enhancing insulin sensitivity.
== Example == While performing a biceps curl, the person lifting the weight would start with a 25 pound dumbbell and do as many repetitions as possible without significantly compromising form. Then a 20-pound weight would be used until exhaustion is reached. One could continue to "drop" down as many times as they wish, but usually the weight is not dropped to below fifty percent of their one rep maximum.
Graphite oxide (GO), formerly called graphitic oxide or graphitic acid, is a compound of carbon, oxygen, and hydrogen in variable ratios, obtained by treating graphite with strong oxidizers and acids for resolving of extra metals. The maximally oxidized bulk product is a yellow solid with C:O ratio between 2.1 and 2.9, that retains the layer structure of graphite but with a much larger and irregular spacing. The bulk material spontaneously disperses in basic solutions or can be dispersed by sonication in polar solvents to yield monomolecular sheets, known as graphene oxide by analogy to graphene, the single-layer form of graphite. Graphene oxide sheets have been used to prepare strong paper-like materials, membranes, thin films, and composite materials. Initially, graphene oxide attracted substantial interest as a possible intermediate for the manufacture of graphene. The graphene obtained by reduction of graphene oxide still has many chemical and structural defects which is a problem for some applications but an advantage for some others.
Sources: en.wikipedia.org
It is a four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine. The chain is unmodified and contains only standard proteinogenic residues, which makes it straightforward to produce by solid-phase synthesis and to characterise by standard peptide methods.
Epitalon and epithalon both circulate, and the difference reflects transliteration of a name coined in Russian-language publications. Reference to the extract it derives from, epithalamin, explains the shared stem. Databases and suppliers are inconsistent, so a search for one spelling alone may miss relevant entries.
No. Epithalamin is a multi-component preparation obtained from pineal tissue, and its exact composition is not fully characterised. Epitalon is a single defined tetrapeptide described as a short synthetic counterpart of that extract, so the two are related in origin but not interchangeable in identity.
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.