AEDG raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-10-20 and is reviewed periodically as new material appears.
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.
Human data are limited to small studies, often without the randomization, blinding, or control groups expected in contemporary clinical research. Reported outcomes have included changes in melatonin levels, immune markers, and subjective measures, but sample sizes were generally too small to support firm conclusions. Some reviews treat the peptide as promising while noting methodological weaknesses; others question whether the observed effects are specific. The compound is frequently discussed in longevity-focused communities, where enthusiasm often outpaces the published evidence. Separating established findings from speculation is therefore important when reading summaries of this research.
Epitalon emerged from research conducted in Saint Petersburg by Vladimir Khavinson and colleagues, who studied short peptides as potential regulators of aging. The work built on epithalamin, a pineal gland extract reported to influence neuroendocrine function. Epitalon was designed as a synthetic counterpart with a defined sequence, allowing reproducible experiments that extracts could not support. Early publications described effects on melatonin rhythms and lifespan in animal models. These findings circulated mainly in Russian-language journals during the 1990s, which limited their visibility among English-speaking researchers.
| 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 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.
Regulatory treatment differs by country. No formulation of epitalon holds a marketing authorisation as a medicine in the United States or the European Union, where material sold for laboratory use is handled as a research chemical and is not intended for human consumption. In Russia, several short peptide preparations from the same institute's peptide series are registered medicinal products, and epitalon appears in that national context. Elsewhere it is frequently offered as a cosmetic ingredient, a category with lighter requirements. Advertising claims about longevity or disease prevention are restricted in most jurisdictions, which limits how sellers describe the compound.
Freeze-dried epitalon is normally kept at minus twenty degrees Celsius in a sealed, desiccated container, protected from light. Short excursions at ambient temperature during shipping are generally tolerated, but repeated warming and cooling cycles encourage moisture uptake, which shortens shelf life. Once dissolved, the peptide is far less stable than the solid: aqueous solutions are subject to hydrolysis and to deamidation at the aspartate and glutamate residues. Working solutions are therefore held refrigerated and used within days, and repeated freezing and thawing of the same vial is best avoided.
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 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.
An example is the trp gene in bacteria. When there is a high level of tryptophan in the region, it is inefficient for the bacterium to synthesize more. When the RNA polymerase binds and transcribes the trp gene, the ribosome will start translating. (This differs from eukaryotic cells, where RNA must exit the nucleus before translation starts.) The attenuator sequence, which is located between the mRNA leader sequence (5' UTR) and trp operon gene sequence, contains four domains, where domain 3 can pair with domain 2 or domain 4. The attenuator sequence at domain 1 contains instruction for peptide synthesis that requires tryptophans. A high level of tryptophan will permit ribosomes to translate the attenuator sequence domains 1 and 2, allowing domains 3 and 4 to form a hairpin structure, which results in termination of transcription of the trp operon. Since the protein coding genes are not transcribed due to rho independent termination, no tryptophan is synthesised. In contrast, a low level of tryptophan means that the ribosome will stall at domain 1, causing the domains 2 and 3 to form a different hairpin loop structure that does not signal termination of transcription. Therefore, the rest of the operon will be transcribed and translated, so that tryptophan can be produced. Thus, domain 4 is an attenuator. Without domain 4, translation can continue regardless of the level of tryptophan. The attenuator sequence has its codons translated into a leader peptide, but is not part of the trp operon gene sequence.
=== Brand names === It is marketed under several brand names, including, Brozam, Lectopam, Lexomil, Lexotan, Lexilium, Lexaurin, Brazepam, Rekotnil, Bromaze, Somalium, Lexatin, Calmepam, Zepam and Lexotanil.
The monoepoxide of treosulfan (EBDM) exhibited greater brain penetration than the parent compound, with tissue-to-plasma ratios of 0.25 in young adult rats and 0.50 in juvenile rats. The elimination half-life of treosulfan in patients is short, averaging 1.5–2.0 h. The apparent elimination half-life of the biologically active epoxides is similar to that of treosulfan, reflecting the phenomenon of formation rate-limited elimination. The most common side effects include infections, nausea (feeling sick), stomatitis (inflammation of the lining of the mouth), vomiting, diarrhea, and abdominal pain (belly ache). Tiredness, febrile neutropenia (low white blood cell counts with fever) and high blood levels of bilirubin (a breakdown product of red blood cells) are also seen in more than 1 in 10 adults, and rash also affects more than 1 in 10 children. The most common adverse reactions include musculoskeletal pain, stomatitis, pyrexia, nausea, edema, infection, and vomiting. Selected grade 3 or 4 nonhematological laboratory abnormalities include increased GGT, increased bilirubin, increased ALT, increased AST, and increased creatinine. Treosulfan was authorized for medical use in the European Union in June 2019, and approved for medical use in the United States in January 2025.
==== Policy Interventions ==== Banning non-therapeutic antibiotics in agriculture (e.g., European Union's 2006 growth promoter ban). Incentivizing development of new antibiotics and alternatives (e.g., vaccines, bacteriophages).
=== Trophozoite stage === The trophozoite stage is the infective phase for humans, during which the organism can actively feed and replicate. The trophozoite attaches to the olfactory epithelium, follows the axons of olfactory receptor neurons through the cribriform plate in the nasal cavity, and enters the brain. This reproductive stage of the protozoan organism transforms around 25 °C (77 °F), and thrives best around 42 °C (108 °F), multiplying through binary fission. Trophozoites are characterized by a nucleus surrounded by a flexible membrane. They move via pseudopodia, extending parts of their cell membrane (pseudopods) and filling them with protoplasm to facilitate locomotion. Pseudopods form in the direction of movement. In their free-living state, trophozoites feed on bacteria. In tissues, they appear to phagocytize (enclose and digest) red blood cells and cause tissue damage either through the release of cytolytic substances or by direct cell-to-cell contact using cytolytic membrane proteins. As trophozoites, N. fowleri may develop about one to 12 structures on their membrane known as amoebastomes, also referred to as "suckers" or "food cups", which they use for feeding via a trogocytosis-like mechanism.
Sources: en.wikipedia.org
== Prognosis == Prognosis varies with the type of amyloidosis and the affected organ system. Prognosis for untreated AL cardiac amyloidosis is poor, with a median survival of six months. More specifically, AL amyloidosis can be classified as stage I, II or III based on cardiac biomarkers like Nt-proBNP and cardiac troponin. Survival diminishes with increasing stage, but recent advancements in treatments have improved median survival rates for stages I, II, and III, to 91.2, 60, and 7 months respectively. Outcomes in a person with AA amyloidosis depend on the underlying disease, organ(s) affected, and correlate with the concentration of serum amyloid A protein. People with ATTR, mutant ATTR and wild-type ATTR have a better prognosis when compared to people with AL and may survive for over a decade. Survival time is not associated with gender or age, however, some measures of reduced heart function are associated with a shorter survival time. Senile systemic amyloidosis was determined to be the primary cause of death for 70% of people over 110 who have been autopsied.
Oxycodone is the most widely recreationally used opioid in America. In the United States, more than 12 million people use opioid drugs recreationally. The U.S. Department of Health and Human Services estimates that about 11 million people in the U.S. consume oxycodone in a non-medical way annually. Opioids were responsible for 49,000 of the 72,000 drug overdose deaths in the U.S. in 2017. In 2007, about 42,800 emergency room visits occurred due to "episodes" involving oxycodone. In 2008, recreational use of oxycodone and hydrocodone was involved in 14,800 deaths. Some of the cases were due to overdoses of the acetaminophen component, resulting in fatal liver damage. In September 2013, the US Food and Drug Administration (FDA) released updated labeling guidelines for long-acting and extended-release opioids requiring manufacturers to remove moderate pain as an indication for use, instead stating the drug is for "pain severe enough to require daily, around-the-clock, long term opioid treatment". The updated labeling does not restrict physicians from prescribing opioids for moderate pain, as needed. Reformulated OxyContin is causing some recreational users to change to heroin, which is cheaper and easier to obtain.
=== Legal status === On 17 September 2020, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for melphalan. The applicant for this medicinal product is Adienne S.r.l. S.U. Melphalan was approved for medical use in the European Union in November 2020.
=== Cardiac fibrosis and other fibroses === Some serotonergic agonist drugs cause fibrosis anywhere in the body, particularly the syndrome of retroperitoneal fibrosis, as well as cardiac valve fibrosis. In the past, three groups of serotonergic drugs have been epidemiologically linked with these syndromes. These are the serotonergic vasoconstrictive antimigraine drugs (ergotamine and methysergide), the serotonergic appetite suppressant drugs (fenfluramine, chlorphentermine, and aminorex), and certain anti-Parkinsonian dopaminergic agonists, which also stimulate serotonergic 5-HT2B receptors. These include pergolide and cabergoline, but not the more dopamine-specific lisuride. As with fenfluramine, some of these drugs have been withdrawn from the market after groups taking them showed a statistical increase of one or more of the side effects described. An example is pergolide. The drug was declining in use since it was reported in 2003 to be associated with cardiac fibrosis. Two independent studies published in The New England Journal of Medicine in January 2007 implicated pergolide, along with cabergoline, in causing valvular heart disease. As a result of this, the FDA removed pergolide from the United States market in March 2007. (Since cabergoline is not approved in the United States for Parkinson's Disease, but for hyperprolactinemia, the drug remains on the market. Treatment for hyperprolactinemia requires lower doses than that for Parkinson's Disease, diminishing the risk of valvular heart disease).
Sources: en.wikipedia.org
==== Anxiety disorders ==== Tiagabine may be prescribed off-label to treat certain anxiety disorders, such as panic disorder and social anxiety disorder. Tiagabine may be used alongside selective serotonin reuptake inhibitors (SSRIs), serotonin–norepinephrine reuptake inhibitors (SNRIs), or benzodiazepines for anxiety. The drug was ineffective for generalized anxiety disorder.
A large number of benzodiazepine derivatives have been synthesised and their structure-activity relationships explored in detail. This chart contains binding data for benzodiazepines and related drugs investigated by Roche up to the late 1990s (though in some cases the compounds were originally synthesised by other companies such as Takeda or Upjohn). Other benzodiazepines are also listed for comparison purposes, but it does not however include binding data for;
The name hemoglobin (or haemoglobin) is derived from the words heme (or haem) and globin, reflecting the fact that each subunit of hemoglobin is a globular protein with an embedded heme group. Each heme group contains one iron atom, that can bind one oxygen molecule through ion-induced dipole forces. The most common type of hemoglobin in mammals contains four such subunits.
Alice in Chains released their debut album, Facelift, in August 1990 through Columbia Records. Inspired by the music of Black Sabbath, Deep Purple, and Motörhead, the album was initially unsuccessful; the band's first live performances were local shows and festivals around Seattle. Their first tour came as a supporting act to Extreme for a month. Extreme themselves had yet to reach fame and were playing their first tour; neither band drew well. Alice in Chains followed with an opening slot on a tour with Iggy Pop in November 1990, but the band was similarly received with indifference. Their fortunes began to turn when the video for their breakout single, "Man in the Box", landed regular rotation on MTV, beating Blue Murder for a slot on the channel's "Buzz Bin". With newfound momentum, the group secured two supporting slots on two high-profile tours: first, they were selected to join thrash metal bands Anthrax, Megadeth, and Slayer, on the Clash of the Titans Tour in mid-1991, having replaced opening act Death Angel after the band was involved in a bus accident that left its drummer Andy Galeon critically injured and unable to perform. They were then appointed to a slot on Van Halen's For Unlawful Carnal Knowledge Tour later that year; Van Halen frontman Sammy Hagar personally selected the band. Sales of Facelift increased drastically, and by September 1991, it had been certified gold by the Recording Industry Association of America (RIAA).
== Venom == The venom of the Wagler's pit viper contains four novel peptides (Waglerins 1-4). The Waglerins produce fatal respiratory paralysis of adult mice. An initial study indicated that micromolar concentrations of Waglerin 1 act both pre- and postsynaptically to inhibit transmission across rat neuromuscular junctions. However, Waglerin-1 is a more potent inhibitor of transmission across the mouse neuromuscular junction. A subsequent study demonstrated that Waglerin-1 inhibited the adult mouse endplate response to acetylcholine with an IC50 of 50 nanomolar. In striking contrast, transmission across neuromuscular junctions of neonatal or transgenic mice lacking the adult acetylcholine receptor was not altered by micromolar concentrations of Waglerin-1. Biochemical studies demonstrated that the exquisite selectivity of Waglerin-1 for the adult mouse acetylcholine receptor relies upon several amino acid residues unique to the epsilon subunit of the adult mouse acetylcholine receptor. Waglerin-1's selectivity for the epsilon-subunit containing acetylcholine receptor of adult mice is complemented by selectivity of small peptide toxins purified from the venom of Conus geographus and Conus pergrandis for the gamma-subunit containing acetylcholine receptor of neonatal skeletal muscle. The Waglerins and complementary conotoxins are useful tools to discover the contribution of acetylcholine receptor subunits to synaptogenesis. In addition, study of the Waglerins and related toxic peptides may lead to the discovery of novel molecular targets for drug development.
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.
Vladimir Khavinson and colleagues at research institutes in Saint Petersburg developed and studied the peptide. Their program examined short peptides as regulators of aging and neuroendocrine function. Epitalon was one of several compounds produced by that group.