tetrapeptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-09-05 and is reviewed periodically as new material appears.
The most frequently cited laboratory finding is that AEDG increased telomerase activity and extended telomere length in cultured human somatic cells. That work used fetal fibroblast strains and reported changes in enzyme activity alongside altered division counts. Replication by unrelated groups has been limited, and the published record is largely a single-laboratory series rather than a multi-centre programme. The result supports a hypothesis about peptide influence on gene expression in cell culture; it does not by itself establish an effect on telomere length in living animals or in people.
Animal and clinical reports appear mainly in Russian-language journals from the 1990s and 2000s, covering endpoints such as melatonin rhythm, lifespan in aged rodents, and retinal function. Many of these papers involve small groups, lack blinding or placebo comparison, and are difficult to retrieve through indexed databases. Review articles published in English generally summarise the claims without reanalysing the underlying data. Because no large randomised trial exists, the clinical importance of these reported effects stays unresolved and is properly described as an open question.
No national medicines regulator has approved epitalon as a therapeutic product. It is generally distributed as a research chemical, and in some jurisdictions selling peptides for human consumption without approval is restricted or prohibited. Certificates of analysis accompanying commercial material vary in which tests are performed, and independent verification of identity and purity is uncommon. Statements about anti-ageing or disease-prevention benefits on vendor pages are marketing claims rather than regulatory findings, a distinction that shapes how the compound is discussed in scientific and popular sources alike.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not an approved drug | Marketed in most countries as a research chemical |
| Main literature language | Russian and English | Early reports concentrated in Russian journals |
| Typical stated purity | ≥95% by HPLC | Supplier declaration, seldom independently verified |
| Principal studied endpoint | Telomerase activity in vitro | Measured in cultured human cells |
| Reported administration routes | Subcutaneous, intranasal | Described in exploratory use reports |
Regulatory status varies by country and is not harmonized. Epitalon is not an approved drug in major Western jurisdictions. In some countries it is sold as a research chemical, and in others it has appeared in products marketed for other categories. This inconsistent status means that purity, labeling accuracy, and documentation differ widely between suppliers, and verification of identity and purity through independent analysis is the usual way buyers assess a given lot.
Epitalon appears in the literature primarily through a small number of research groups, most of them associated with the St. Petersburg Institute of Bioregulation and Gerontology. Publications describe cell culture experiments, animal studies, and a limited number of small human studies. Independent replication outside this network is sparse. As a result, reviews of the topic usually separate descriptive reports of observed effects from the question of whether those effects generalize, and they note the difficulty of comparing studies that use different preparations and endpoints.
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.
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.
Stability of the tetrapeptide follows ordinary peptide chemistry rather than any unusual structural feature. The aspartate-glycine pair is prone to aspartimide formation under mildly basic or neutral conditions, and deamidation can follow, altering both mass and chromatographic retention. Dry lyophilised powder kept at or below minus twenty degrees Celsius is the usual handling recommendation, with repeated freeze-thaw cycles avoided. Once dissolved in neutral aqueous buffer, degradation proceeds over days to weeks depending on pH and temperature, while acidic conditions generally slow the aspartimide route. A formal stability-indicating study has not been published in the indexed literature.
Because epitalon has no pharmacopoeial monograph, quality assessment depends on supplier documentation and independent testing. Certificates of analysis typically report a purity figure from a single chromatographic run, a measured mass and sometimes an appearance description, but methods and acceptance criteria are not harmonised across vendors. Third-party laboratories can repeat identity and purity measurements, and mismatches between labelled and measured peptide content have been described for research peptides generally. What constitutes adequate identity confirmation for a molecule of this size stays an open question, since mass agreement alone does not separate closely related sequences.
Identity testing for epitalon relies on reversed-phase high-performance liquid chromatography for purity and mass spectrometry for mass confirmation. Because the sequence contains no tryptophan or tyrosine, ultraviolet detection at 280 nanometres is insensitive, so chromatographic methods usually monitor absorbance near 214 nanometres, where the peptide backbone absorbs. Electrospray ionisation or matrix-assisted laser desorption/ionisation then checks the intact mass against the expected value near 390 daltons. Peptide mapping or amino acid analysis after acid hydrolysis can supplement these measurements, although such confirmatory work is seldom reported on commercial certificates of analysis.
== Contraindications == It is contraindicated if there has been a past history of angioedema; heart conduction disorders (e.g. sick sinus syndrome, second- or third-degree heart block); bradycardia; severe heart failure or coronary artery disease. Also: Raynaud's syndrome, intermittent claudication, epilepsy, depression, Parkinson's disease, glaucoma. Use in pregnancy is discouraged. Moxonidine passes into breast milk. Moxonidine should be avoided in patients with moderate to severe renal impairment. Abrupt discontinuation of the drug should also be avoided. If concomitant treatment with a beta blocker has to be stopped, the beta blocker should be discontinued first, then moxonidine after a few days. Alcohol may potentiate the hypotensive effects of Moxonidine. Excess mortality has been seen in patients with symptomatic heart failure in the MOXCON study. However, the MOXCON trial utilised a very high dose of 3.0 mg daily which is well above the normal dose of 0.2–0.6 mg daily.
Deadlift – 400 kg (882 lb) (2005 Pojedynek Gigantów) Keg drop Deadlift – 295–350 kg (650–771 lb) x 6 lifts in 33.89 seconds (2005 World's Strongest Man) Keg drop Squat – 265–340 kg (584–750 lb) x 7 reps in 21.28 seconds (2007 World's Strongest Man - Group 4) Keg drop Squat – 260–360 kg (573–794 lb) x 7 reps in 27.53 seconds (2005 World's Strongest Man) (former world record) Log lift – 172 kg (379 lb) (2005 Met-Rx Grand Prix) Log lift (for reps) – 130 kg (287 lb) x 14 reps (2006 Moscow Grand Prix) Axle press (for reps) – 140 kg (309 lb) x 11 reps (2006 WSMC Poland) (World Record) Apollon wheel press – 166 kg (366 lb) x 4 reps (2004 Arnold Strongman Classic) Viking press – 150 kg (331 lb) x 12 reps (2007 Mohegan Sun Grand Prix) Kettlebell press – 80 kg (176 lb) x 8 reps (2009 Globe's Strongest Man) Atlas Stones – 5 stones weighing 115–155 kg (254–342 lb) on tall platforms in 21.09 seconds (2006 Strongman Super Series Moscow Grand Prix) (World Record) Ding carry – 160 kg (353 lb) for 90 metres (2005 World's Strongest Man) (World Record) Asia Stone / shield carry – 175 kg (386 lb) for 127.4 metres (2002 World's Strongest Man) (World Record) Africa Stone carry – 175 kg (386 lb) for 110 metres (2000 World's Strongest Man - Group 5) (World Record) Block carry – 180 kg (397 lb) for 80 metre course in 41.32 seconds (2002 Europe's Strongest Man) (World Record) Fridge carry (super yoke) – 410 kg (904 lb) for 20 metres in 15.29 seconds (2005 World's Strongest Man) Timber carry – 392 kg (864 lb) (40' ramp) in 22.93 seconds (Raw grip) (2006 Arnold Strongman Classic) Wheelbarrow carry (no straps) – 300 kg (661 lb) (25m course) in 15.50 seconds (2003 IFSA Finland Grand Prix) (World Record) Farmer's walk (no straps) – 150 kg (331 lb) per each hand for 60m course in 19.90 seconds (2006 Strongman Super Series Poland Grand Prix) (World Record) Farmer's walk (no straps) – 137.5 kg (303 lb) per each hand for 70m course in 22.48 seconds (2003 Strongman Super Series Finland Grand Prix) (World Record) Super Yoke – 360 kg (794 lb) for 20 meters in 7.66 seconds (2006 World Strongman Cup Federation, Poland) (World Record) Medicine Ball Toss – 23 kg (51 lb) for 4.88 meters (2004 Arnold Strongman Classic) Power Stairs – (225 kg (496 lb) total of 14 steps) – 40.94 seconds (2008 World's Strongest Man) (World Record) Power Stairs – (230 kg (507 lb) total of 23 shallow steps) – 26.33 seconds (2006 World's Strongest Man) (World Record) Power Stairs – (200 kg (441 lb), 230 kg (507 lb) & 250 kg (551 lb) total of 15 high steps) – 31.22 seconds (2004 Europe's Strongest Man) (World Record) Power Stairs – (225 kg (496 lb), 250 kg (551 lb) & 275 kg (606 lb) total of 15 steps) – 28.56 seconds (2005 Nautilus Grand Prix) (World Record) Tyre Flip – 380 kg (838 lb) Tyre x 8 flips - 20.81 seconds (2004 Holland Champions Trophy) and 400 kg (882 lb) Tyre x 8 flips - 22.87 seconds (2006 Moscow Grand Prix) (former world records) Flip & drag – 400 kg (882 lb) tyre x 4 flips and 300 kg (661 lb) anchor & chain drag for 30 meters – 39.01 seconds (2002 World's Strongest Man) (world record) Conan's wheel (Basque circle) – 360 kg (794 lb) 765° rotation (2006 World Strongman Cup Russia) (World Record) Conan's wheel (Basque circle) – 317.5 kg (700 lb) 1,203° rotation (2003 Strongman Super Series Holland Grand Prix) (World Record) Conan's wheel (Basque circle) – 300 kg (661 lb) 1,440° rotation (2002 World's Strongest Man - Group 5) (former world record) Train pull – 16,000 kg (35,274 lb) for 25 meter course in 30.78 seconds (2003 World's Strongest Man) (World Record) Truck pull – 24,000 kg (52,911 lb) for 20 meter course in 26.05 seconds (2003 IFSA Strongman World Record Breakers) (World Record) Plane pull – 40,000 kg (88,185 lb) for 25 meter course in 36.67 seconds (2008 World's Strongest Man) (World Record) During training: (Self-claims)
The reduced ability of the kidneys to excrete sodium and water causes retention (medicine) of these substances and thus an increase in blood volume, which ultimately leads to an increase in blood pressure. About two thirds of all cats with CNE are affected. High blood pressure in turn leads to increased connective tissue formation. A potassium deficiency or excess calcium secondary to other kidney damage also causes further damage to the kidney tissue.
Sources: en.wikipedia.org
1 element (tin) has 10 stable isotopes 5 elements have 7 stable isotopes apiece 7 elements have 6 stable isotopes apiece 11 elements have 5 stable isotopes apiece 9 elements have 4 stable isotopes apiece 5 elements have 3 stable isotopes apiece 16 elements have 2 stable isotopes apiece 26 elements have 1 single stable isotope. These last 26 are thus called monoisotopic elements. The mean number of stable isotopes for elements which have at least one stable isotope is 251/80 = 3.1375.
Within the United States, the Patient Protection and Affordable Care Act of 2010 created an abbreviated approval pathway for biological products shown to be biosimilar to, or interchangeable with, an FDA-licensed reference biological product. Researchers are optimistic that the introduction of biosimilars will reduce medical expenses to patients and the healthcare system.
Czechoslovakia was occupied by the Wehrmacht, and real power was vested in Hitler's personal representative, the Reichsprotektor. During the occupation, between 294,000 to 320,000 citizens were murdered, the majority of them Jews. Reprisal killings were especially harsh after the assassination of Reinhard Heydrich, including the infamous Lidice massacre. Large numbers were drafted for slave labour in Germany. In March 1944 Germany extended the occupation of Czechoslovakia to Hungary in Operation Margarethe, then to Slovakia in August 1944 following the Slovak National Uprising. The occupation ended with the surrender of Germany at the end of World War II.
== Elements considered possibly essential for humans but not confirmed == Many ultratrace elements have been suggested as essential, but such claims have usually not been confirmed. Definitive evidence for efficacy comes from the characterization of a biomolecule containing the element with an identifiable and testable function. One problem with identifying efficacy is that some elements are innocuous at low concentrations and are pervasive (examples: silicon and nickel in solid and dust), so proof of efficacy is lacking because deficiencies are difficult to reproduce. Some elements were once thought to have a role with unknown biochemical nature, but the evidence has not always been strong. For example, it was once thought that arsenic was probably essential in mammals, but it seems to be only used by microbes; and while chromium was long thought to be an essential trace element based on rodent models, and was proposed to be involved in glucose and lipid metabolism, more recent studies have called this into question. It may still have a role in insulin signalling, but the evidence is not clear, and it only seems to occur at doses not found in normal diets. Boron is essential to plants, but not humans, although depletion-repletion studies in humans showed benefits to bone and brain health. Non-essential elements can sometimes appear in the body when they are chemically similar to essential elements (e.g. Rb+ and Cs+ replacing Na+), so that essentiality is not the same thing as uptake by a biological system.
Sources: en.wikipedia.org
Erin Shammel Baker is an American bioanalytical chemist specializing in developing ion mobility-mass spectrometry hybrid instruments for biological and environmental applications. Baker is an expert in the research of perfluoroalkyl and polyfluoroalkyl substances analysis.
a metal, such as palladium or nickel, in bulk, thin films or powder; and deuterium, hydrogen, or both, in the form of water, gas or plasma. Electrolysis cells can be either open cell or closed cell. In open cell systems, the electrolysis products, which are gaseous, are allowed to leave the cell. In closed cell experiments, the products are captured, for example by catalytically recombining the products in a separate part of the experimental system. These experiments generally strive for a steady state condition, with the electrolyte being replaced periodically. There are also "heat-after-death" experiments, where the evolution of heat is monitored after the electric current is turned off. The most basic setup of a cold fusion cell consists of two electrodes submerged in a solution containing palladium and heavy water. The electrodes are then connected to a power source to transmit electricity from one electrode to the other through the solution. Even when anomalous heat is reported, it can take weeks for it to begin to appear—this is known as the "loading time," the time required to saturate the palladium electrode with hydrogen (see "Loading ratio" section). The Fleischmann and Pons early findings regarding helium, neutron radiation and tritium were never replicated satisfactorily, and its levels were too low for the claimed heat production and inconsistent with each other.
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Sources: en.wikipedia.org
Small studies with human participants have been reported, chiefly in Russian-language journals, but they are limited in size and design. No large randomised controlled trial with published results is available.
The most reproducible biochemical observation comes from cultured cells, where the peptide was reported to raise telomerase activity. Whether this translates into measurable health effects in animals or humans is not established.
It is offered as a research chemical for laboratory use, which places it outside the approval pathways applied to medicines. Buyers should expect documentation to differ between suppliers.
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.