Pineal peptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-10-29. 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 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.
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.
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.
| 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 whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
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.
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.
Reported biological findings come mainly from cell culture and rodent experiments. Those studies describe changes in telomerase catalytic subunit expression, melatonin rhythm amplitude, and antioxidant enzyme activity after peptide exposure. Human data are sparse and consist of small trials with limited blinding and inconsistent endpoints. The proposed mechanisms remain hypotheses rather than established facts, and there is no consensus on whether effects observed in animals carry over to people. Independent replication outside the original research groups is limited, which is a recognised gap in the published literature.
The parent extract epithalamin was characterised as a low-molecular-weight fraction of pineal tissue rather than a single defined chemical entity. Researchers fractionated it and tested successive fragments for activity, a screening approach typical of peptide discovery work in that era. Epitalon emerged from that process as one of the shorter sequences of interest. Because the original extract was never fully resolved into individual components, claims about which constituent drives a given effect rest on inference. This distinction matters when reading older reports that attribute extract observations to the tetrapeptide itself.
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.
==== Neurochemical and neuroendocrine ==== Some neurochemical abnormalities that occur in fibromyalgia also regulate mood, sleep, and energy, thus explaining why mood, sleep, and fatigue problems are commonly co-morbid with fibromyalgia. Serotonin is the most widely studied neurotransmitter in fibromyalgia. It is hypothesized that an imbalance in the serotonergic system may lead to the development of fibromyalgia. There is also some data that suggests altered dopaminergic and noradrenergic signaling in fibromyalgia. Supporting the monoamine related theories is the efficacy of monoaminergic antidepressants in fibromyalgia. Glutamate/creatine ratios within the bilateral ventrolateral prefrontal cortex were found to be significantly higher in fibromyalgia patients than in controls and may disrupt glutamate neurotransmission. Studies on the neuroendocrine system and HPA axis in fibromyalgia have been inconsistent. The depressed function of the HPA axis results in adrenal insufficiency and potentially chronic fatigue.
=== Biochemistry === Guanidine exists protonated, as guanidinium, in solution at physiological pH. Guanidinium chloride (also known as guanidine hydrochloride) has chaotropic properties and is used to denature proteins. Guanidinium chloride is known to denature proteins with a linear relationship between concentration and free energy of unfolding. In aqueous solutions containing 6 M guanidinium chloride, almost all proteins lose their entire secondary structure and become randomly coiled peptide chains. Guanidinium thiocyanate is also used for its denaturing effect on various biological samples. Recent studies suggest that guanidinium is produced by bacteria as a toxic byproduct. To alleviate the toxicity of guanidinium, bacteria have developed a class of transporters known as guanidinium exporters or Gdx proteins to expel the extra amounts of this ion to the outside of the cell. Gdx proteins are highly selective for guanidinium and mono-substituted guanidinyl compounds and share an overlapping set of non-canonical substrates with drug exporter EmrE.
The Democratic Party failed to win an absolute majority of seats and Afonso Costa chose not to form government. Instead, António Maria da Silva of the Democratic Party became Prime Minister on 6 February, leading a minority government with the support of the Reconstitution Party, the Catholic Centre Party, the Regionalist Party and some independents. However, the government failed to serve a full term after being forced to resign following a motion of no confidence in November 1923. Further instability resulted in seven different governments holding office in the subsequent period until the 1925 elections.
Sources: en.wikipedia.org
==== Odd atomic number ==== 53 stable nuclides have an even number of protons and an odd number of neutrons. They are a minority in comparison to the even-even isotopes, which are about 3 times as numerous. Among the 41 even-Z elements that have a stable nuclide, only two elements (argon and cerium) have no even-odd stable nuclides. One element (tin) has three. There are 24 elements that have one even-odd nuclide and 13 that have two odd-even nuclides. Of 35 primordial radionuclides there exist four even-odd nuclides (see table at right), including the fissile 23592U. Because of their odd neutron numbers, the even-odd nuclides tend to have large neutron capture cross-sections, due to the energy that results from neutron-pairing effects. These stable even-proton odd-neutron nuclides tend to be uncommon by abundance in nature, generally because, to form and enter into primordial abundance, they must have escaped capturing neutrons to form yet other stable even-even isotopes, during both the s-process and r-process of neutron capture, during nucleosynthesis in stars. For this reason, only 19578Pt and 94Be are the most naturally abundant isotopes of their element. 48 stable odd-proton-even-neutron nuclides, stabilized by their paired neutrons, form most of the stable isotopes of the odd-numbered elements; the very few odd-proton-odd-neutron nuclides comprise the others. There are 41 odd-numbered elements with Z = 1 through 81, of which 39 have stable isotopes (technetium (43Tc) and promethium (61Pm) have no stable isotopes).
It is also used off-label in the management of moderate to severe cases of serotonin syndrome, a complex of symptoms associated with the use of serotonergic drugs, such as selective serotonin reuptake inhibitors (and monoamine oxidase inhibitors), and in cases of high levels of serotonin in the blood resulting from a serotonin-producing carcinoid tumor. There is uncertainty about the proper dose of cyproheptadine for treatment of serotonin syndrome, with doses of 4 to 16 mg having been employed but doses of 20 to 30 mg possibly actually being necessary based on positron emission tomography (PET) imaging research. Cyproheptadine has sedative effects and can be used to treat insomnia similarly to other centrally-acting antihistamines. The recommended dose for this use is 4 to 8 mg.
== Health concerns == The manipulation of the gut flora is complex and may cause bacteria-host interactions. Although probiotics, in general, are considered safe, there are concerns about their use in certain cases. Some people, such as those with compromised immune systems, short bowel syndrome, central venous catheters, heart valve disease and premature infants, may be at higher risk for adverse events. Rarely, consumption of probiotics may cause bacteremia, and sepsis, potentially fatal infections in children with lowered immune systems or who are already critically ill.
Sources: en.wikipedia.org
=== Transmission of signal === The presence of hormone or multiple hormones enables a response in the receptor, which begins a cascade of signaling. The hormone receptor interacts with different molecules to induce a variety of changes, such as an increase or decrease of nutrient sources, growth, and other metabolic functions. These signaling pathways are complex mechanisms mediated by feedback loops where different signals activate and inhibit other signals. If a signaling pathway ends with the increase in production of a nutrient, that nutrient is then a signal back to the receptor that acts as a competitive inhibitor to prevent further production. Signaling pathways regulate cells through activating or inactivating gene expression, transport of metabolites, and controlling enzymatic activity to manage growth and functions of metabolism.
=== Enamels === During the Meiji era, Japanese cloisonné enamel reached a technical peak, producing items more advanced than any that had existed before. The period from 1890 to 1910 was known as the "Golden age" of Japanese enamels. Artists experimented with pastes and with the firing process to produce ever larger blocks of enamel, with less need for cloisons (enclosing metal strips). During this period, enamels with a design unique to Japan, in which flowers, birds and insects were used as themes, became popular. Designs also increasingly used areas of blank space. The two most famous enamelers of this era were Namikawa Yasuyuki and Namikawa Sōsuke, whose family names sound the same but who were not related. Namikawa Sōsuke promoted his work as technically innovative and adopted a style resembling fine paintings. Namikawa Yasuyuki was more conservative, opting for geometrical patterns but gradually becoming more pictorial during his career. Along with the two Namikawa, the Ando Cloisonné Company has produced many high-quality cloisonné works. Namikawa Yasuyuki's Vase with Birds and Flowers of the Four Seasons is one of the finest examples of cloisonné from this era. It won a gold medal at the 1900 Paris Exposition and was designated as an Important Cultural Property in 2025.
== Publications == Maroon has published over 340 peer-reviewed scientific articles, some of which may be found in the United States National Library of Medicine's publication database; his H-index, a measure of scientific research impact, is 74 (as of June 2025). As of early 2026, his work has garnered more than 27,300 total citations. Currently, Maroon is working with Dr. Pravat K. Mandal and has proposed oxidative stress as the underlying pathogenesis of Alzheimer's disease and Parkinson's disease.
=== Main === Evan Peters as Cooper Madsen, a former Navy SEAL and FBI agent investigating deaths linked to "the Beauty" Hudson Barry as Cooper after the transformation Anthony Ramos as Antonio / the Assassin, an enforcer working for "the Corporation" who took the drug soon after it was invented. He is 65 years old in a 30-something year old's body. Teddy Cañez as the Assassin before the transformation Jeremy Pope as Jeremy, an outsider drawn into the chaos surrounding the epidemic Jaquel Spivey as Jeremy before the transformation Rebecca Hall as Jordan Bennett, an FBI agent and Cooper's partner Jessica Alexander as Jordan after the transformation Ashton Kutcher as Byron Forst / the Corporation, a tech billionaire tied to the "Beauty" drug who took it three years ago to keep himself from aging Vincent D'Onofrio as Byron before the transformation
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.
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.