The short version of tetrapeptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-03-09. Anything still debated is marked as such rather than presented as settled.
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 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 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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C14H22N4O9 | Derived from the four-residue sequence |
| Molar mass | About 390.35 g/mol | Free peptide, counter-ion not included |
| Appearance | White to off-white powder | Lyophilised solid from aqueous solution |
| Water solubility | Freely soluble | Short, polar peptide chain |
| Common synonyms | AEDG; epithalone | Catalogues use the names interchangeably |
Epitalon is a synthetic tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, commonly abbreviated AEDG. Its design traces to epithalamin, a peptide fraction prepared from bovine pineal gland extracts that researchers in Saint Petersburg began investigating in the 1970s. The compound has a molecular formula of C14H22N4O9 and a nominal molecular mass near 390 daltons. It holds no approved drug status in the United States or the European Union, and material sold under this name is generally offered as a research chemical rather than a finished pharmaceutical product.
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.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
Under the Second Republic's constitution, the president was restricted to a single term of four years. To avoid this restriction and remain in power, President Louis-Napoléon overthrew the second Republic in a process beginning with the 1851 self-coup d'état; he became known as Emperor Napoleon III of the Second French Empire from 1852.
Honey collection is an ancient activity, long preceding the honey bee's domestication; this traditional practice is known as honey hunting. A Mesolithic rock painting in a cave in Valencia, Spain, dating back at least 8,000 years, depicts two honey foragers collecting honey and honeycomb from a wild bees' nest. The figures are depicted carrying baskets or gourds, and using a ladder or series of ropes to reach the nest. Humans followed the greater honeyguide bird to wild beehives; this behavior may have evolved with early hominids. The oldest known honey remains were found in Georgia during the construction of the Baku–Tbilisi–Ceyhan pipeline: archaeologists found honey remains on the inner surface of clay vessels unearthed in an ancient tomb, dating back between 4,700 and 5,500 years. In ancient Georgia, several types of honey were buried with a person for journeys into the afterlife, including linden, berry, and meadow-flower varieties. The first written records of beekeeping are from ancient Egypt, where honey was used to sweeten cakes, biscuits, and other foods and as a base for unguents in Egyptian hieroglyphs. The dead were often buried in or with honey in Egypt, Mesopotamia and other regions. Bees were kept at temples to produce honey for temple offerings, mummification and other uses. In southern Illyria (present day Albania), the Iron Age Illyrian tribe of the Abroi were known for preparing mead, a wine from honey, as documented by Hecataeus of Miletus in the 6th century BCE. In ancient Greece, honey was produced from the Archaic to the Hellenistic periods.
Andrew went into business with his father in the United States in 1973, opening their first Panda Inn restaurant in Pasadena, California. At the beginning, business was lacking to the degree that Andrew had to offer special deals and freebies so that customers would dine at Panda Inn. In 1982, Peggy joined Andrew in the restaurant business. While operating Panda Inn, Andrew became acquainted with then-UCLA head football coach Terry Donahue, as well as Terry's brother Dan, who happened to be in the real estate business. It was because of this connection that in 1983, Donahue Schriber Real Estate, the manager of the Glendale Galleria, invited the Cherngs to develop a fast-food version of Panda Inn for the Galleria's food court, and Panda Express was launched that October. A second location was opened two years later at the Westside Pavilion in 1985. The chain has steadily expanded across the United States since then. Chef Andy Kao claims to have developed the original Chinese-American orange chicken recipe at a Panda Express in Hawaii in 1987.At first, Panda Express restaurants were found solely in food courts in major shopping malls. During the late 1980s and early 1990s, the Cherngs began experimenting with supermarket-based branches, through a deal with Vons, and then stand-alone restaurant locations. In 1997, the company opened its first stand-alone, drive-through restaurant, in Hesperia, California. Today less than 2% of its restaurants are in malls.
Sources: en.wikipedia.org
The Indian Army has its origins in the years after the Indian Rebellion of 1857, often called the Indian Mutiny in British histories, when in 1858 the Crown took over direct rule of British India from the East India Company. Before 1858, the precursor units of the Indian Army were units controlled by the Company and were paid for by their profits. These operated alongside units of the British Army, funded by the British government in London. The three Presidency armies remained separate forces, each with its own Commander-in-Chief. Overall operational control was exercised by the Commander-in-Chief of the Bengal Army, who was formally the Commander-in-Chief of the East Indies. From 1861, most of the officer manpower was pooled in the three Presidential Staff Corps. After the Second Afghan War a Commission of Enquiry recommended the abolition of the presidency armies. The Ordnance, Supply and Transport, and Pay branches were by then unified. The Punjab Frontier Force was under the direct control of the Lieutenant-Governor of the Punjab during peacetime until 1886, when it came under the Commander-in-Chief, India. The Hyderabad Contingent and other local corps remained under direct governmental control. Standing higher formations—divisions and brigades—were abandoned in 1889. No divisional staffs were maintained in peacetime, and troops were dispersed throughout the sub-continent, with internal security as their main function. In 1891 the three staff corps were merged into one Indian Staff Corps.
=== Other antibiotics === Alternatives to fosfomycin include nitrofurantoin, pivmecillinam, and co-amoxiclav in oral treatment of urinary-tract infections associated with extended-spectrum beta-lactamase. In a separate study, CRE were treated with colistin, amikacin, and tigecycline, and emphasizes the importance of using gentamicin in patients undergoing chemotherapy or stem-cell therapy procedures. While colistin had shown promising activity against carbapenemase-producing isolates, more recent data suggest a resistance to it is already emerging and it will soon become ineffective. Using another antibiotic concomitantly with carbapenem can help prevent the development of carbapenem resistance. One specific study showed a higher rate of carbapenem resistance when using meropenem alone compared with combination therapy with moxifloxacin. In addition, several drugs were tested to gauge their effectiveness against CRE infections. In vitro studies have shown that rifampin has synergistic activity against carbapenem-resistant E. coli and K. pneumoniae. However, more data are needed to determine if rifampin is effective in a clinical setting. Several new agents are in development. The main areas where scientists are focusing is new β-lactamase inhibitors with activity against carbapenemases. Some of these include MK-7655, NXL104, and 6-alkylidenepenam sulfones. The exact way they affect the carbapenemases is unknown. Another experimental agent with activity against CRE is eravacycline.
In 1842, Shanghai became a treaty port, thus developing into an international commercial city. By the early 20th century, it was the largest city and the largest port in East Asia. In 1949, with the Communist takeover in Shanghai, overseas trade was cut dramatically. The early economic policies of the People's Republic severely hindered Shanghai's infrastructure and capital development.
Sources: en.wikipedia.org
It is a synthetic tetrapeptide built from alanine, glutamate, aspartate and glycine. The four residues are joined by standard peptide bonds, giving a linear chain rather than a branched structure.
The name derives from epithalamin, a pineal gland extract studied in the former Soviet Union. Researchers proposed that short fragments of that extract carried the biological activity of interest.
No major regulatory agency has approved it as a medicine. It is handled as a research chemical, and products sold under this name are not standardised drugs with defined clinical labelling.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine–glutamate–aspartate–glycine, also written AEDG. It was developed in Russian gerontology research and is studied for proposed effects on telomerase, melatonin regulation, and neuroendocrine function. It is not an approved pharmaceutical in the United States or the European Union.