Everything below concerns tetrapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-07-22. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Verification of a sample usually begins with reversed-phase high-performance liquid chromatography, which resolves the peptide from truncated sequences and other impurities and expresses purity as a percentage of total peak area. Mass spectrometry by electrospray ionisation or matrix-assisted laser desorption supplies an independent check, because the measured mass can be compared against the theoretical value for AEDG. Amino acid analysis or tandem mass spectrometry sequencing can confirm residue order. Each of these methods answers a different question: a purity figure does not establish identity, and an identity match does not establish how much of the material is intact peptide.
The molecule is a short, linear, hydrophilic peptide that dissolves readily in water or aqueous buffer. Its principal chemical liabilities are hydrolytic rather than oxidative, since it contains no cysteine, methionine, or tryptophan residues. The aspartate–glycine step is a recognised site for aspartimide formation under mildly acidic or basic conditions, generating isoaspartate and succinimide-related products over time. Desiccated lyophilised powder held at −20 °C is comparatively stable, whereas dilute solutions degrade faster and are best frozen as single-use aliquots rather than thawed repeatedly.
No pharmacopoeial monograph exists for this peptide, so quality rests on the supplier's internal specifications and on whatever independent testing a purchaser arranges. Certificates of analysis differ widely in which tests they report and in the limits applied. The counter-ion introduced during purification, commonly acetate or trifluoroacetate, changes the net peptide content of a given mass of powder, so two samples of equal weight may not contain equal amounts of the active sequence. Third-party laboratories can verify purity, identity, residual solvents, and counter-ion content for a fee, which makes documentation more informative than labelling.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Tetrapeptide, often abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free peptide, unmodified termini |
| Molecular weight | ~390.35 Da | Calculated for the free acid form |
| Appearance | White to off-white powder | Typical lyophilized product form |
| Solubility class | Freely soluble in water | Two acidic residues dominate ionic character |
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
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.
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.
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.
Discussions in the literature often conflate three distinct entities: the pineal extract epithalamin, the isolated tetrapeptide AEDG, and commercial preparations sold under similar names. Reviews citing older Russian-language studies sometimes omit detail on purity, route of administration and control groups, which makes cross-study comparison difficult. Researchers working with the compound generally note the need for independent replication, standardized enzyme assays, and clearer reporting of peptide identity. These caveats are relevant when weighing claims that appear in secondary sources rather than in primary reports.
=== EC 2.6.99: Transferring Other Nitrogenous Groups === EC 2.6.99.1: dATP(dGTP)—DNA purinetransferase EC 2.6.99.2: pyridoxine 5′-phosphate synthase EC 2.6.99.3: O-ureido-L-serine synthase EC 2.6.99.4: Now EC 2.3.1.234, N6-L-threonylcarbamoyladenine synthase.
==== Deficit in fear memories ==== Irvine and colleagues in 2006 showed that preventing autophosphorylation of CaMKII cause mice to have impaired initial learning of fear conditioning. However, after repeated trials, the impaired mice exhibited similar fear memory formation as the control mice. CaMKII may play a role in rapid fear memory, but does not completely prevent fear memory in the long run. In 2004, Rodrigues and colleagues found that fear conditioning increased phosphorylated CaMKII in lateral amygdala synapses and dendritic spines, indicating that fear conditioning could be responsible for regulating and activating the kinase. They also discovered a drug, KN-62, that inhibited CaMKII and prevented acquisition of fear conditioning and LTP.
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Sources: en.wikipedia.org
The giant gourami (Osphronemus goramy) is a species of large gourami native to freshwater habitats in Southeast Asia. It has also been introduced elsewhere. The species is commercially important as a food fish and is also farmed. It can be found in the aquarium trade, as well. The species has been used for weed control on highly invasive aquatic plants like Salvinia molesta, as the giant gourami can be a voracious herbivore. It is capable of breathing moist air, so can survive out of water for long periods. It is much larger than most gouramis (only the other Osphronemus species reach a similar size), growing to a maximum standard length of 80 cm (31 in), though most are only around 45 cm (18 in).
=== Bible verses === In-N-Out prints Bible citations in small print on areas of packaging (such as "John 3:16", "Proverbs 3:5", "Proverbs 24:16", "Nahum 1:7", "Luke 6:35" and "Revelation 3:20"). They are primarily found on the bottom underside of drink cups and the wrappers that hold their burgers together. This practice began in the 1980s during Rich Snyder's presidency, a reflection of the evangelical Christian beliefs held by the Snyder family.
Laminin G domain: all laminin alpha chains (LAMA1, LAMA2, LAMA3, LAMA4, LAMA5), cadherin EGF LAG seven-pass G-type receptors (CELSR1, CELSR2, CELSR3), contactin-associated proteins (CNTNAP1, CNTNAP2, CNTNAP3, CNTNAP3B, CNTNAP4, CNTNAP5), some collagens (COL5A1, COL5A3, COL9A1, COL11A1, COL11A2, COL12A1, COL14A1, COL15A1, COL16A1, COL18A1, COL19A1, COL20A1, COL21A1, COL22A1, COL24A1, COL27A1), crumbs homologs 1 and 2 (CRB1, CRB2), fat homologs (FAT1, FAT2, FAT3, FAT4), NEL-like proteins (NELL1, NELL2), neurexins (NRXN1, NRXN2, NRXN3), slit homologs (SLIT1, SLIT2, SLIT3), thrombospondins (THBS1, THBS2, THBS3, THBS4, TSPEAR), agrin (AGRIN), chondroitin sulfate proteoglycan 4 (CSPG4), eyes shut homolog (EYS), growth arrest-specific protein 6 (GAS6), perlecan (HSPG2), pikachurin (EGFLAM), protein S (PROS1), sex hormone-binding globulin (SHBG) and usherin (USH2A) Laminin N-terminal (domain VI): most laminin chains (LAMA1, LAMA2, LAMA3, LAMA5, LAMB1, LAMB2, LAMB3, LAMB4, LAMC1, LAMC3), most netrins (NTN1, NTN3, NTN4, NTNG1, NTNG2), and usherin (USH2A)
Sources: en.wikipedia.org
Epitalon is a synthetic tetrapeptide composed of four amino acids: alanine, glutamate, aspartate, and glycine. It is written as Ala-Glu-Asp-Gly. The free peptide has a molecular weight of about 390 daltons and is normally supplied as a lyophilized powder.
No. Epitalon is chemically synthesized, not extracted. It was designed as a short synthetic fragment conceptually related to larger pineal peptides studied in the same research tradition, particularly the extract known as epithalamin. The two are distinct materials with different compositions.
The term bioregulator is used in this research tradition for short peptides proposed to influence gene expression or cell function. Epitalon is grouped with other synthetic short peptides under this label. The term reflects a proposed mechanism rather than an established drug classification.
Mass spectrometry provides the identity check, because the observed mass is compared with the theoretical mass of the AEDG sequence. Chromatography separates and quantifies impurities but does not by itself prove which peptide is present. The two techniques are normally used together.