A practical reference on AEDG: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-08-15 and is reviewed periodically as new material appears.
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.
Stability depends strongly on pH, temperature and the presence of oxygen and trace metals. Cleavage of the backbone proceeds faster under neutral to alkaline conditions, whereas acidic solutions tend to slow that reaction. The aspartate and glutamate side chains can undergo deamidation or imide formation over time, generating closely related impurities. Published stability data specific to epitalon are sparse, so the usable life of a given solution is best regarded as an open question that depends on buffer composition, concentration and storage temperature.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography with ultraviolet detection, frequently near 214 nanometers where the peptide bond absorbs. Mass spectrometry, most often with electrospray ionization, confirms the observed molecular mass and helps separate the intact peptide from truncated or modified forms. Amino acid analysis or tandem mass spectrometry can establish residue order. Purity is commonly quoted as an area percentage, yet such values are method-dependent, and comparisons between laboratories require matching column, gradient and detection wavelength.
| 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 |
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.
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.
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.
The four residues give epitalon a molecular formula of C14H22N4O9 and a molecular weight near 390.35 daltons. The presence of two acidic residues, glutamate and aspartate, makes the free peptide strongly acidic, while the alanine and glycine ends provide neutral, nonpolar character. This combination produces a molecule with substantial water solubility. Because there are no cysteine, methionine, or tryptophan residues, the peptide lacks the most common oxidation-sensitive side chains, which simplifies handling compared with many longer peptides.
Madison: University of Wisconsin Press. ISBN 978-0-299-07334-3. Montejo, Esteban (2016). Barnet, Miguel (ed.). Biography of a Runaway Slave: Fiftieth Anniversary Edition. Northwestern University Press. ISBN 978-0-8101-3342-6. Morgan, Kenneth (2007). Slavery and the British Empire: From Africa to America. Oxford University Press. ISBN 978-0-19-156627-1. Postma, Johannes (2005). The Atlantic Slave Trade. University Press of Florida. ISBN 978-0-8130-2906-1. Reséndez, Andrés (2016). The Other Slavery: The Uncovered Story of Indian Enslavement in America. Houghton Mifflin Harcourt. ISBN 978-0-547-64098-3. Rodriguez, Junius P. (2007). Encyclopedia of Slave Resistance and Rebellion. Vol. 2. Westport, Conn: Greenwood Press. ISBN 978-0-313-33273-9. Shell, Robert Carl-Heinz (1994). Children of Bondage: A Social History of the Slave Society at the Cape of Good Hope, 1652–1838. Hanover, NH: University Press of New England [for] Wesleyan University Press. ISBN 978-0-8195-5273-0. Westermann, William Linn (1955). The Slave Systems of Greek and Roman Antiquity. American Philosophical Society. ISBN 978-0-87169-040-1. {{cite book}}: ISBN / Date incompatibility (help) Williams, Eric (2021). Capitalism and Slavery, Third Edition. The University of North Carolina Press. ISBN 978-1469663678. Journal articles and reviews Bartlett, Will (May 1994). "Review: Property and Contract in Economics". Economic and Industrial Democracy. 15 (2): 296–298. doi:10.1177/0143831x94152010. S2CID 220850066. Burczak, Theodore (June 2001).
== Airports == World's Top Airports: Bangkok's Suvarnabhumi Airport (BKK) was ranked number 36 among the world's top 100 airports in 2018. Other ASEAN airports for 2018 were ranked: Singapore Changi Airport, 1; Kuala Lumpur International Airport, 44; Jakarta, 45; Hanoi, 82. Suvarnabhumi was ranked 38 in 2017 and 36 in 2016.
The dissection continues toward the brow and the glabella (the smooth prominence between the eyebrows) until the skin flap is sufficiently mobile to allow its relaxed transposition upon the nose. Under loupe magnification, the distal portion of the forehead flap is de-fatted, down to the subdermal plexus. Yet, the fat-removal should be conservative, especially if the patient is either a tobacco smoker or a diabetic, or both, because such health factors negatively affect blood circulation and tissue perfusion, and thus the timely and correct healing of the surgical scars to the nose. The flap is allowed to perfuse, while the donor site is sutured closed by means of the wide undermining deep to the frontalis muscle. At that time, diluted epinephrine can be injected to the forehead skin, but not to the area(s) near the pedicle of the forehead flap. Moreover, if the distal wound is wider than 25 mm, it usually is not closed by primary intention, with sutures, but is allowed to heal by secondary intention, by re-epithelialisation. The forehead flap is attached to the nasal wound with subcutaneous sutures and skin sutures. If the excess tension of a suture compromises the color of the skin flap, the suture can be loosened, with a skin hook, and observed for 10–15 minutes; if the skin color remains compromised (white), the suture is removed. Upon the complete attachment of the paramedian forehead flap to the nose, the surgical wounds are dressed only with antibiotic ointment. IV.
=== Metabolic actions === SIRT2 suppresses inflammatory responses in mice through p65 deacetylation and inhibition of NF-κB activity. SIRT2 is responsible for the deacetylation and activation of G6PD, stimulating pentose phosphate pathway to supply cytosolic NADPH to counteract oxidative damage and protect mouse erythrocytes.
Sources: en.wikipedia.org
Regarding the last quarter-century of the period outlined by Taylor, his American colleague, diplomatic historian Edward Mead Earle, argued: "During the quarter-century beginning about 1890, Europe and the Far East lived under a precarious balance of power with the result … that the world moved crazily from one crisis to another and finally to catastrophe". Earle concludes: "The balance of power may well land us all in crematory". The balance of power theory prepared catastrophe in 1939 as in 1914, wrote Clarence Streit in his famous Union Now. There is "no more sterile, illusory, fantastic, exploded and explosive peace policy than the balance of power." In 1953, Ernst B. Haas criticized balance of power theory, arguing that international relations works that used the concept were plagued with "philological, semantic, and theoretical confusion." Since 1945, the arguments of Streit and Earle has prevailed over that of Taylor. Atomic scientists launched an all-out attack on the balance-of-power concept:
== Chemistry == 2C-B, also known as 4-bromo-2,5-dimethoxyphenethylamine, is a substituted phenethylamine of the 2C family, also known as the 4-substituted 2,5-dimethoxyphenethylamines. It is a synthetic analogue of the naturally occurring phenethylamine psychedelic mescaline found in peyote and certain other cacti.
However, the amount of radium produced globally has always been small in comparison to other elements, and by the 2010s, annual production of radium, mainly via extraction from spent nuclear fuel, was less than 100 grams. In nature, radium is found in uranium ores in quantities as small as a seventh of a gram per ton of uraninite, and in thorium ores in trace amounts. Radium is not necessary for living organisms, and its radioactivity and chemical reactivity make adverse health effects likely when it is incorporated into biochemical processes because of its chemical mimicry of calcium, due to them both being group 2 elements. As of 2018, other than in nuclear medicine, radium has no commercial applications. Formerly, from the 1910s to the 1970s, it was used as a radioactive source for radioluminescent devices and also in radioactive quackery for its supposed curative power. In nearly all of its applications, radium has been replaced with less dangerous radioisotopes, with one of its few remaining non-medical uses being the production of actinium in nuclear reactors.
Methylphenidate is a psychostimulant drug that is often used in the treatment of ADHD and narcolepsy and occasionally to treat obesity in combination with diet restraints and exercise. Its effects at therapeutic doses include increased focus, increased alertness, decreased appetite, decreased need for sleep and decreased impulsivity. Methylphenidate is not usually used recreationally, but when it is used, its effects are similar to those of amphetamines. Methylphenidate acts as a norepinephrine–dopamine reuptake inhibitor (NDRI), by blocking the norepinephrine transporter (NET) and the dopamine transporter (DAT). Methylphenidate has a higher affinity for the dopamine transporter than for the norepinephrine transporter, and so its effects are mainly due to elevated dopamine levels caused by the inhibited reuptake of dopamine, however increased norepinephrine levels also contribute to various of the effects caused by the drug. Methylphenidate is sold under a number of brand names including Ritalin. Other versions include the long lasting tablet Concerta and the long lasting transdermal patch Daytrana.
=== 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.
Sources: en.wikipedia.org
=== Special populations === It is recommended that women with active tuberculosis who are pregnant or breastfeeding take isoniazid. Preventive therapy should be delayed until after giving birth. Nursing mothers excrete a relatively low and non-toxic concentration of INH in breast milk, and their babies are at low risk for side effects. Both pregnant women and infants being breastfed by mothers taking INH should take vitamin B6 in its pyridoxine form to minimize the risk of peripheral nerve damage. Vitamin B6 is used to prevent isoniazid-induced B6 deficiency and neuropathy in people with a risk factor, such as pregnancy, lactation, HIV infection, alcoholism, diabetes, kidney failure, or malnutrition. People with liver dysfunction are at a higher risk for hepatitis caused by INH, and may need a lower dose. Levels of liver enzymes in the bloodstream should be frequently checked in daily alcohol drinkers, pregnant women, IV drug users, people over 35, and those who have chronic liver disease, severe kidney dysfunction, peripheral neuropathy, or HIV infection since they are more likely to develop hepatitis from INH.
=== Special cases === Idiopathic infantile hypercalcemia is caused by a mutation of the CYP24A1 gene, leading to a reduction in the degradation of vitamin D. Infants who have such a mutation have an increased sensitivity to vitamin D and in case of additional intake a risk of hypercalcaemia. The disorder can continue into adulthood.
==== Impact on growers ==== The US-supported coca eradication policy has been criticized for its negative impact on the livelihood of South American coca growers, in a region where the coca leaf has traditionally been chewed and used in tea and for religious, medicinal and nutritional purposes by locals Making traditional coca cultivation illegal is viewed as unjust. In areas where forced eradication also destroyed other food or market crops, without providing an alternative, farmers were left starving and destitute.
Monazite geochronology is a dating technique to study geological history using the mineral monazite. It is a powerful tool in studying the complex history of metamorphic rocks particularly, as well as igneous, sedimentary and hydrothermal rocks. The dating uses the radioactive processes in monazite as a clock. The uniqueness of monazite geochronology comes from the high thermal resistance of monazite, which allows age information to be retained during the geological history. As monazite grows, it forms successive generations of different compositions and ages, commonly without erasing the previous ones, forming zonation patterns in monazite. Because of the age zonation, dating should be done on individual zones, rather than the whole crystal. Also, textures of monazite crystals may represent certain type of events. Therefore, direct sampling techniques with high spatial resolution are required, in order to study these tiny zones individually, without damaging the textures and zonations. The advantage of monazite geochronology is the ability to relate monazite compositions with geological processes. Finding the ages of compositional zones can mean finding the ages of geological processes.
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.
The dry powder is typically held at -20 degrees Celsius or lower, protected from light and moisture. Allowing a sealed vial to reach room temperature before opening reduces condensation on its contents. Conditions stated on a supplier certificate of analysis take precedence over general guidance.