Everything below concerns epithalamin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-05-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
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.
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.
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.
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.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
== External links == World Health Organization guidelines for the availability and accessibility of controlled substances Reference list to the previous publication Links to all language versions of the previous publication CDC Guideline for Prescribing Opioids for Chronic Pain — United States, 2016
== Medical uses == CEEs are a form of hormone therapy used in women. It is used most commonly in postmenopausal women who have had a hysterectomy to treat hot flashes, and burning, itching, and dryness of the vagina and surrounding areas. It must be used in combination with a progestogen in women who have not had a hysterectomy. For women already taking the medication, it can be used to treat osteoporosis, although it is not recommended solely for this use. Some lesser known uses are as a means of high-dose estrogen therapy in the treatment of breast cancer in both women and men and in the treatment of prostate cancer in men. It has been used at a dosage of 2.5 mg three times per day (7.5 mg/day total) for prostate cancer. CEEs are specifically approved in countries such as the United States and Canada for the treatment of moderate to severe vasomotor symptoms (hot flashes) and vulvovaginal atrophy (atrophic vaginitis, atrophic urethritis) associated with menopause, hypoestrogenism due to hypogonadism, ovariectomy, or primary ovarian failure, abnormal uterine bleeding, the palliative treatment of metastatic breast cancer in women, the palliative treatment of advanced androgen-dependent prostate cancer in men, and the prevention of postmenopausal osteoporosis. The intravenous formulation of CEEs is specifically used to rapidly limit bleeding in women with hemorrhage due to dysfunctional uterine bleeding.
=== Clinical environment === Guidelines from the UCSF Transgender Care Center state the importance of visibility in chosen gender identity for transgender or non-binary patients. Safe environments include a two-step process in collecting gender identity data by differentiating between personal identity and assignments at birth for medical histories. Common techniques recommended are asking patients their preferred name, pronouns, and other names they may go by in legal documents. In addition, visibility of non-cisgender identities is defined by the work environment of the clinic. Front-desk staff and medical assistants will interact with patients, for which these guidelines recommend appropriate training. The existence of at least one gender-neutral bathroom also shows consideration of patients with non-binary gender identities.
The defective protein can be transmitted by contaminated harvested human brain products, corneal grafts, dural grafts, or electrode implants and pituitary human growth hormone, which has been replaced by recombinant human growth hormone that poses no such risk. It can be familial (fCJD) or it may appear without clear risk factors (sporadic form: sCJD). In the familial form, a mutation has occurred in the gene for PrP, PRNP, in that family. All types of CJD are transmissible irrespective of how they occur in the person. It is thought that humans can contract the variant form of the disease by eating food from animals infected with bovine spongiform encephalopathy (BSE), the bovine form of TSE, also known as mad cow disease. However, it can also cause sCJD in some cases. Cannibalism has also been implicated as a transmission mechanism for abnormal prions, causing the disease known as kuru, once found primarily among women and children of the Fore people in Papua New Guinea, who previously engaged in funerary cannibalism. While the men of the tribe ate the muscle tissue of the deceased, women and children consumed other parts, such as the brain, and were more likely than men to contract kuru from infected tissue. Prions, the infectious agent of CJD, may not be inactivated using routine surgical instrument sterilization procedures.
=== Molecular electronics applications === Molecular 'switch' peptides can be made into nanoswitches when an electronic component is incorporated. Metal nanocrystals can be covalently linked to the peptides to make them electronically responsive; research is currently being conducted on how to develop electronically controlled molecules and molecular 'machines' using such molecular 'switches'. Peptide nanofibers can also be used as growth templates for a range of inorganic materials, such as silver, gold, platinum, cobalt, nickel, and various semiconducting materials. Electrons transferring aromatic moieties can also be attached to the side chains of peptides to form conducting nanostructures that can transfer electrons in a certain direction. Metal and semiconductor binding peptides have been used for the fabrication of nanowires. Peptides self-assemble into hollow nanotubes to act as casting molds; metal ions that migrate inside the tube undergo reduction to metallic form. The peptide 'mold' can then be enzymatically destroyed to produce a metal nanowire of about 20 nm diameter. This has been done making gold nanowires and this application is especially significant because nanowires at this scale cannot be made by lithography. Researchers have also successfully developed multi-layer nanocables with a silver core nanowire, a peptide insulation layer, and a gold outer coat. This is done by reducing AgNO3 inside nanotubes, and then bounding a layer of thiol-containing peptides with gold particles attached.
Sources: en.wikipedia.org
=== Tetracyclic antidepressants === Mirtazapine has demonstrated anxiolytic effect comparable to SSRIs while rarely causing or exacerbating anxiety. Mirtazapine's anxiety reduction tends to occur significantly faster than SSRIs.
Primarily through the suspension of Qatari liquefied natural gas (LNG) and the closure of the Strait of Hormuz, several publications including the BBC, PBS, Deutsche Welle, Euronews, Financial Times and Bruegel, along with banks and think tanks, have projected that the continent will enter an energy crisis in 2026 similar to the 2022 energy crisis that followed the War in Ukraine. The conflict coincided with historically low European gas storage levels – estimated at just 30% capacity following a harsh 2025–2026 winter – causing Dutch TTF gas benchmarks to nearly double to over €60/MWh by mid-March. On 26 March, the European Commission advised its member states to fill their gas storages early to avoid price spikes later in the year.
Since 1990, the American Dialect Society (ADS) has designated one or more words or terms to be the "Word of the Year" in the United States. In addition to the "Word of the Year", the society also selects words in other categories such as "Most Outrageous," "Most Creative," and "Most Likely to Succeed."
== Distribution == Relaxin-3 is mostly expressed within neurons of the brain, where it is packaged into dense cored vesicles and trafficked along axons where it can be detected in presynaptic vesicles before release onto target neurons, characteristic of a neurotransmitter. The largest number of relaxin-3-positive neurons in the rodent brain are within a region of the pontine brainstem known as the nucleus incertus, while smaller populations are present within the pontine raphe, periaqueductal grey, and an area dorsal to the substantia nigra. From these centres, relaxin-3 innervates a broad range of brain regions which are also rich in RXFP3 mRNA/binding sites, including the extended limbic system and the septohippocampal pathway.
Sources: en.wikipedia.org
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.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
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.