This is a working overview of AEDG tetrapeptide, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-11-28. Anything still debated is marked as such rather than presented as settled.
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.
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.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Epitalon is a synthetic tetrapeptide whose sequence is alanine-glutamate-aspartate-glycine, written in single-letter code as AEDG. The four residues are joined by three peptide bonds, giving a linear backbone with no branching and no disulfide bridges. Its calculated molecular mass for the free form is approximately 390.3 daltons, a figure that rises when the compound is supplied as an acetate or trifluoroacetate salt. Because the chain is short, the molecule is defined entirely by its residue order rather than by any folded three-dimensional structure.
| 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 |
The proposed relationship between epitalon and pineal function is a central part of its background. Khavinson's group reported that short peptides corresponding to regions of larger pineal proteins could influence gene expression in cells. Epitalon was framed as a synthetic analogue of an active fragment rather than a direct isolation product. Whether the tetrapeptide reproduces the effects of the parent extract is an open question, because comparative studies are limited and the parent extract itself is not a single defined substance.
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 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.
On March 10, 2023, Silicon Valley Bank (SVB) failed after a bank run, marking the third-largest bank failure in United States history and the largest since the 2008 financial crisis. It was one of three bank failures, along with Silvergate Bank and Signature Bank, in March 2023 in the United States. Seeking higher investment returns from its burgeoning deposits, SVB had dramatically increased its holdings of long-term securities since 2021, accounting for them on a hold-to-maturity basis. The market value of these bonds decreased significantly through 2022 and into 2023 as the Federal Reserve raised interest rates to curb an inflation surge, causing unrealized losses on the portfolio. Higher interest rates also raised borrowing costs throughout the economy and some Silicon Valley Bank clients started pulling money out to meet their liquidity needs. To raise cash to pay withdrawals by its depositors, SVB announced on Wednesday, March 8 that it had sold over US$21 billion worth of securities, borrowed $15 billion, and would hold an emergency sale of some of its treasury stock to raise $2.25 billion. The announcement, coupled with warnings from prominent Silicon Valley investors, caused a bank run as customers withdrew funds totaling $42 billion by the following day. On the morning of March 10, the California Department of Financial Protection and Innovation seized SVB and placed it under the receivership of the Federal Deposit Insurance Corporation (FDIC). An additional $100 billion were expected to be withdrawn during Friday.
== Signs and symptoms == The classic presentation of COP is the development of nonspecific systemic (e.g., fevers, chills, night sweats, fatigue, weight loss) and respiratory (e.g. difficulty breathing, cough) symptoms in association with filling of the lung alveoli that is visible on chest x-ray. This presentation is usually so suggestive of an infection that the majority of patients with COP have been treated with at least one failed course of antibiotics by the time the true diagnosis is made. Symptoms are usually subacute, occurring over weeks to months with dry cough (seen in 71% of people), dyspnea (shortness of breath)(62%) and fever (44%) being the most common symptoms.
== First recorded observation == In his 14 June 1680 letter to the Royal Society, Antonie van Leeuwenhoek described an experiment he carried out by filling two identical glass tubes about halfway with crushed pepper powder, to which some clean rain water was added. Van Leeuwenhoek sealed one of the glass tubes with a flame and left the other open. Several days later, he discovered in the open glass tube 'a great many very little animalcules, of divers sort having its own particular motion.' Not expecting to see any life in the sealed glass tube, Van Leeuwenhoek saw to his surprise 'a kind of living animalcules that were round and bigger than the biggest sort that I have said were in the other water.' The conditions in the sealed tube had become quite anaerobic due to the consumption of oxygen by aerobic microorganisms. In 1913, Martinus Beijerinck repeated Van Leeuwenhoek's experiment and identified Clostridium butyricum as a prominent anaerobic bacterium in the sealed pepper infusion tube liquid. Beijerinck commented:
Cottage cheese is a type of fresh cheese with a mild flavor and a creamy, heterogeneous texture made from skimmed milk – hence the low milkfat content. It is made by adding an acid – like vinegar or lemon juice – to the milk which causes the milk proteins (curds) to separate from the liquid (whey). The curds are then drained and mixed with cream and salt, giving cottage cheese its slightly tangy taste and creamy texture. The addition of a "dressing" to the curd grains is primarily responsible for the taste of the finished food. Cottage cheese is not aged. It was first called 'cottage cheese' in 1831, likely originating from Pennsylvania Dutch immigrants making cheese curds to spread on snacks in their homesteads (cottages). Cottage cheese can be relatively low in milkfat and calories for the high amount of protein it provides, and is a rich source of vitamin B12. Cottage cheese comes in different fat levels, including low–fat and fat–free – but even an original 'full fat' version has fewer calories than a chunk of hard cheese or wedge of soft cheese. Cottage cheese is a versatile nutritious food readily added to fruit, vegetables, bread and breakfast items, pastas, sauces, and desserts.
Sources: en.wikipedia.org
Talks quickly broke down, and final efforts in October to achieve a settlement floundered; the Smith government remained unwilling to accept the five principles of independence, and the British government argued it would settle for nothing less. On 11 November 1965 the Cabinet of Rhodesia issued a unilateral declaration of independence (UDI). The UDI was immediately denounced as an "act of rebellion against the Crown" in the United Kingdom, and Wilson promised that the illegal action would be short-lived. However, given its self-governing status Rhodesia had no longer been within the United Kingdom's direct sphere of influence for some time, and the façade of continued British rule was rendered a constitutional fiction by UDI. In light of these circumstances, Wilson quickly realised his ability to assert direct leverage over the incumbent Rhodesian government was limited. On 12 October 1965, the United Nations General Assembly had noted the repeated threats of the Rhodesian authorities "to declare unilaterally the independence of Southern Rhodesia, in order to perpetuate minority rule", and called upon Wilson to use all means at his disposal (including military force) to prevent the Rhodesian Front from asserting independence. After UDI was proclaimed, UN officials branded the Rhodesian government as an "illegal racist minority regime" and called on member states to voluntarily sever economic ties with Rhodesia, recommending sanctions on petroleum products and military hardware.
The nucleophilic phosphine attacks the azide at the electrophilic terminal nitrogen. Through a four-membered transition state, N2 is lost to form an aza-ylide. The unstable ylide is hydrolyzed to form phosphine oxide and a primary amine. However, this reaction is not immediately bioorthogonal because hydrolysis breaks the covalent bond in the aza-ylide.
Since birds are highly visible and common animals, humans have had a relationship with them since the dawn of man. Sometimes, these relationships are mutualistic, like the cooperative honey-gathering among honeyguides and African peoples such as the Borana. Other times, they may be commensal, as when species such as the house sparrow have benefited from human activities. Several species have reconciled to habits of farmers who practice traditional farming. Examples include the Sarus Crane that begins nesting in India when farmers flood the fields in anticipation of rains, and the woolly-necked storks that have taken to nesting on a short tree grown for agroforestry beside fields and canals. Several bird species have become commercially significant agricultural pests, and some pose an aviation hazard. Human activities can also be detrimental, and have threatened numerous bird species with extinction (hunting, avian lead poisoning, pesticides, roadkill, wind turbine kills and predation by pet cats and dogs are common causes of death for birds). Birds can act as vectors for spreading diseases such as psittacosis, salmonellosis, campylobacteriosis, mycobacteriosis (avian tuberculosis), avian influenza (bird flu), giardiasis, and cryptosporidiosis over long distances. Some of these are zoonotic diseases that can also be transmitted to humans.
== Sweetness properties == Miraculin, unlike curculin (another taste-modifying agent), is not sweet by itself, but it can change the perception of sourness to sweetness, even for a long period after consumption. The duration and intensity of the sweetness-modifying effect depends on various factors, such as miraculin concentration, duration of contact of the miraculin with the tongue, and acid concentration. Miraculin reaches its maximum sweetness with a solution containing at least 4*10−7 mol/L miraculin, which is held in the mouth for about 3 minutes. Maximum is equivalent in sweetness to a 0.4 mol/L solution of sucrose. Miraculin degrades permanently via denaturation at high temperatures and at pH below 3 or above 12. Although the detailed mechanism of the taste-inducing behavior is unknown, it appears the sweet receptors are activated by acids which are related to sourness, an effect remaining until the taste buds perceive a neutral pH. Sweeteners are perceived by the human sweet taste receptor, hT1R2-hT1R3, which belongs to G protein-coupled receptors, modified by the two histidine residues (i.e. His30 and His60) which participate in the taste-modifying behavior. One site maintains the attachment of the protein to the membranes while the other (with attached xylose or arabinose) activates the sweet receptor membrane in acid solutions.
== History == Cannabinol (CBN) was the first cannabinoid isolated in the late 1800s, with its structure elucidated in the 1930s and synthesized by 1940. In 1942, Roger Adams discovered cannabidiol (CBD), followed by Raphael Mechoulam's identification of CBD stereochemistry in 1963 and THC stereochemistry in 1964. CBD and THC are produced independently from the precursor CBG, not via conversion.
Sources: en.wikipedia.org
== Steric complementarity == In her third paper on cyclols (1936), Wrinch noted that many "physiologically active" substances such as steroids are composed of fused hexagonal rings of carbon atoms and, thus, might be sterically complementary to the face of cyclol molecules without the amino-acid side chains. Wrinch proposed that steric complementarity was one of chief factors in determining whether a small molecule would bind to a protein. Wrinch speculated that proteins are responsible for the synthesis of all biological molecules. Noting that cells digest their proteins only under extreme starvation conditions, Wrinch further speculated that life could not exist without proteins.
Also, in the post-war years, communication between English and German scientists was poor. Following the new reports, the method of gas chromatography spread widely and Cremer's work slowly gained more recognition. Cremer and her students continued their work on developing both the methods and theories behind gas chromatography over the next two decades and led to many of contemporary, common use ideas used in gas chromatography. Cremer and her group created the phrase "relative retention time" and how to calculate the peak area through multiplying the peak's height by the width of the peak at half height. Additionally, they demonstrated the relationship between measurement and column temperature and also invented head space analysis.
These passages include the questioning of Jesus as to whether he is Elijah, John the Baptist, Jeremiah, or another prophet (Matthew 16:13–15 and John 1:21–22) and, less clearly (while Elijah was said not to have died, but to have been taken up to heaven), John the Baptist being asked if he is not Elijah (John 1:25). Around the 11–12th century in Europe, several reincarnationist movements were persecuted as heresies, through the establishment of the Inquisition in the Latin Christendom. These included the Cathar, Paterene or Albigensian church of western Europe, the Paulician movement, which arose in Armenia, and the Bogomils in Bulgaria. Christian sects such as the Bogomils and the Cathars, who professed reincarnation and other gnostic beliefs, were referred to as "Manichaean", and are today sometimes described by scholars as "Neo-Manichaean". As there is no known Manichaean mythology or terminology in the writings of these groups there has been some dispute among historians as to whether these groups truly were descendants of Manichaeism.
== Data management == The FDA has collected a large amount of data through the decades. The OpenFDA project was created to enable easy access of the data for the public and was officially launched in June 2014.
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 peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.