AEDG is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-10-11. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Epitalon is a synthetic tetrapeptide with the residue sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its monoisotopic mass is approximately 390.35 daltons, and it is usually supplied as a lyophilised trifluoroacetate or acetate salt. The compound was derived from a pineal gland extract called epithalamin, a heterogeneous preparation investigated in the former Soviet Union. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology described the tetrapeptide as a constituent fragment of that extract. Commercial material is offered as a laboratory reagent rather than as a finished pharmaceutical product.
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.
| 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 |
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.
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.
== Medical uses == Pindolol is used for hypertension in the United States, Canada, and Europe, and also for angina pectoris outside the United States. When used alone for hypertension, pindolol can significantly lower blood pressure and heart rate, but the evidence base for its use is weak as the number of subjects in published studies is small. In some countries, pindolol is also used for arrhythmias and prophylaxis of acute stress reactions. It has been used to treat anxiety as well.
, the first step is to linearise around the disease-free equilibrium (DFE), but for the infected subsystem of non-linear ODEs which describe the production of new infections and changes in state among infected individuals. Epidemiologically, the linearisation reflects that
Aminoglycoside resistance is generally mediated by a resistance gene that inactivates the antibiotic via chemical modification. A wide range of such aminoglycoside modifying enzymes are known, including nucleotidyltranferases, phosphotransferases, or acetyltransferases: all enzymes that attach extra chemical groups to the molecule. New antibiotics have been developed based on the knowledge of some of these enzymes, incorporating structural changes that prevent specific groups of resistance enzymes from modifying the drug.
19 October – The SNP appoints Carol Beattie, a former chief executive of Stirling Council, as interim chief executive following the resignation of Murray Foote. 20 October – The UK government announces plans to appoint a minister to oversee the building of HS2, as well as confirming it will not reinstate the route's Birmingham to Manchester leg. The Sunday Times reports that Rushanara Ali has given up responsibility for managing building safety after survivors of the Grenfell tower fire called for her to stand down following an article that highlighted her attendance at the Franco-British Colloque, a conference that brings together senior politicians, civil servants and business leaders. 21 October – A Freedom of Information request reveals that Suella Braverman sent government documents to her private email account 127 times while she was Attorney General, potentially breaching the ministerial code. 22 October – The Welsh Government pays a £19m tax bill for the environment agency, Natural Resources Wales, following a HM Revenue and Customs investigation into how the agency hired specialist contractors. The UK signs what it has described as a "landmark defence agreement" with Germany. 23 October – Charles III and Camilla arrive in Samoa for a state visit, where the King will preside over the 2024 Commonwealth Heads of Government Meeting. The Senedd votes 26–19 to defeat a motion calling for a new law to allow assisted dying in England and Wales.
Sources: en.wikipedia.org
Cadmium is a strong neutron poison and in fact control rods are often made out of cadmium, making the accumulation of cadmium in fuel of particular concern for the maintenance of stable neutron economy. Cadmium is also a chemically poisonous heavy metal, but given the number of neutron absorptions required for transmutation, it is not a high priority target for deliberate transmutation.
As researchers, usually with little time, usually conduct these tasks themselves and manually and the, largely cosmetic, unstandardized changes are required before, not after, the paper is accepted for publication, the study proposes journals start allowing "free-format submissions". A study (25 May) highlights a list of problematic persuasive methods in academic articles, such as exaggerating the importance of the work or insufficient contextualization by "Not citing previous work that decreases the perceived novelty of the current work".
The Ghana Stock Exchange is the fifth largest on continental Africa and third largest in sub-Saharan Africa, having a market capitalisation of GH¢ 57.2 billion or CN¥180.4 billion in 2012, with the South Africa JSE Limited ranked first. The Ghana Stock Exchange was the second best performing stock exchange in Sub-Saharan Africa in 2013. Ghana produces cocoa. It is the second largest producer of cocoa globally and its ICCO membership helps in its international cocoa trade. Ghana is classified as a middle-income country. Services account for 50% of GDP, followed by manufacturing (24.1%), extractive industries (5%), and taxes (20.9%). Ghana's economy is characterized by a growing manufacturing sector and the export of digital technology products. The country is also engaged in the assembly and export of automobiles and ships. Ghana's economy benefits from a range of resource-rich exports, including industrial minerals and agricultural products, with cocoa being a primary commodity. The nation is a producer and exporter of petroleum and natural gas. The information and communications technology (ICT) sector plays a role in Ghana's industrial landscape, with companies such as Rlg Communications, a state-affiliated digital technology corporation, leading in the production of tablet computers, smartphones, and consumer electronics. Urban electric cars have been manufactured in Ghana since 2014. Ghana announced plans to issue government debt by way of social and green bonds in autumn of 2021, making it the first African country to do so.
A moving average measurement may also be used, in which the average results for patient samples are measured at certain intervals. Assuming that the characteristics of the patient population remain roughly the same over time, the average should remain constant. Large shifts in the average value can indicate instrument problems.
BioDuro provides end-to-end CRDMO services spanning early discovery through clinical development. Rather than list individual assays or sub-services, the company groups its offerings into several major business units.
Sources: en.wikipedia.org
However, while LSD and salvinorin A may have comparative potencies, in the sense that both can produce their effects at low dosages, they are otherwise quite different. The two substances are not chemically similar or related, as salvinorin A is found naturally in a single plant while LSD is chemically semisynthesized from lysergamides like ergotamine. They are ingested in different ways and produce different effects, which manifest themselves over different timescales. For example, the effects of salvia when smoked typically last for only a few minutes as compared to LSD, whose effects can persist for 8 to 12 hours.
Cell-Based Bone Tissue Engineering Clinical Tissue Engineering Center. State of Ohio Initiative for Tissue Engineering (National Center for Regenerative Medicine). Organ Printing. Archived 28 August 2008 at the Wayback Machine. Multi-site NSF-funded initiative. LOEX Center. Université Laval Initiative for Tissue Engineering.
=== Energy manipulation === A major feature of its post-scarcity society, the Culture is obviously able to gather, manipulate, transfer and store vast amounts of energy. While not explained in detail in the novels, this involves antimatter and the "energy grid", a postulated energy field dividing the universe from neighboring anti-matter universes, and providing practically limitless energy. Transmission or storage of such energy is not explained, though these capabilities must be powerful as well, with tiny drones capable of very powerful manipulatory fields and forces. The Culture also uses various forms of energy manipulation as weapons, with "gridfire", a method of creating a dimensional rift to the energy grid, releasing astronomical amounts of energy into a region of non-hyperspace, being described as a sort of ultimate weapon more destructive than collapsed antimatter bombardment. One character in Consider Phlebas refers to gridfire as "the weaponry of the end of the universe". Gridfire resembles the zero-point energy used within many popular science fiction stories.
==== Chromatography ==== High-performance liquid chromatography can be used to separate unconjugated and conjugated bilirubin, but the method has insufficient bias and precision to be a gold standard reference method, and it is too laborious and expensive for routine use.
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 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.