If you have been reading about ACTH(4-10) and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-05-02. Where a claim depends on a specific study, the study is described rather than over-claimed.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
C-reactive protein (CRP) Procalcitonin (PCT) Presepsin soluble CD14 soluble CD163 soluble CD206 (mannose receptor) soluble TREM-1 The link between gut microbiota constitution and liver health (Particularly in Cirrhosis) has been well described, however specific biomarkers for prediction of Cirrhosis still requires further research. A 2014 study identified 15 microbial biomarkers from the gut microbiota. These could potentially be used to discriminate patients with liver cirrhosis from healthy individuals.
==== Cytokines ==== Illness can cause inflammation, which often involves an increase in cytokines such as TNFa, IL-1, and IL-6. Cytokines are implicated in NTIS. IL-1β has been shown to decrease liver D1, as well as thyroid hormone receptor (THR) levels. IL-6 and TNFa downregulate D1 and suppress TSH, are negatively correlated with fT3, and are positively correlated with rT3. NF-κB also inhibits D1, and decreases the expression of Thyroid receptors α and β. IFNy inhibits thyroid and Tg release, and also inhibits the upregulation of TSH receptors.
==== Context ==== The announcement of the new cabinet is an attempt to resolve a political crisis between Pedro Castillo and the Congress of the Republic. On 24 November 2022, President Castillo delivered a speech to the nation in which he announced that he accepted the resignation of Aníbal Torres and also the appointment of a new cabinet. The resigning Prime Minister wanted to provoke a vote of confidence in Congress so that it would analyze a constitutional reform project to annul Congress in order to trigger referendums, particularly on the Constituent Assembly, a historic project of Castillo's, but the vote of confidence was denied by the presidency of Congress, dominated by the centre-right and the right. In that same speech, Pedro Castillo evokes the interpretation of Congress's decision not to allow the vote of confidence desired by the President of the council as an "express refusal of confidence" and considers this cabinet change legitimate.
== Toxicity == SRTX-b and SRTX-a are highly lethal and cause cardiac arrest and death in mice within minutes of intravenous administration, LD50 for mice was detected for about 0.015 mg/kg body weight and LD50 0.3 mg/kg in case of SRTX-c.
=== Central & East Indo-Pacific === 2024 Vietnamese export of pangasius maw has increased to about US$58,000,000, with 38% going to China and the rest to Thailand, Malaysia, Singapore and the USA. The Vietnam News Agency claims that the falling totoaba population has incentivized Chinese import of alternative maw. The island and seas of New Guinea see significant fish maw production. Since 2012, in and around the Kikori River delta of Papua New Guinea, the scaly croaker Nibea squamosa has been targeted in gillnetting for its extremely high-priced maw, selling for as much as US$15,615 per kilogram.
Sources: en.wikipedia.org
Carrier females do develop mild symptoms after 2–3 months of age, but mostly do not go on to develop kidney failure. The disease is caused by a defect in the structure of the type-IV collagen fibrils of the glomerular basement membrane. As a consequence, the collagen fibrils of the glomerular basement membrane are unable to form cross-links, so the structural integrity is weakened and the membrane is more susceptible to "wear-and-tear" damage. As the structure of the basement membrane begins to degenerate, plasma proteins are lost in the urine and symptoms begin to appear. Affected males appear healthy for the first three months of life, but then symptoms start to appear and worsen as the disease progresses: the dog becomes lethargic and muscle wastage occurs, as a result of proteinuria. From three months of age onwards, a reduced glomerular filtration rate is detected, indicative of progressive kidney failure. Clinically, proteinuria is found in both sexes from the age of three to four months; in dogs older than this, kidney failure in combination with more or less pronounced hearing loss occurs swiftly and death at the age of 8 to 15 months is expected. In heterozygous females, the disease develops slowly. The disease can be treated to slow down the development by use of cyclosporine A and ACE inhibitors, but not stopped. If a carrier female is mated with a healthy stud dog, the female offspring have a 50% chance of being carriers for the disease, and any male offspring have a 50% chance of being affected by the disease. A genetic test is available for this disease.
== Metabolism == As first discovered in 1882, pyroglutamic acid can be formed by heating glutamic acid at 180 °C, which results in the loss of a molecule of water. In living cells, it is derived from glutathione through the action of an enzyme, γ-glutamyl cyclotransferase. Pyroglutamic acid may function in glutamate storage, and acts to oppose the action of glutamate, including in the brain. It also acts on the brain's cholinergic system; Amyloid β containing pyroglutamic acid is increased in Alzheimer's disease; this may be part of the disease process. Increased levels of pyroglutamic acid in the blood, leading to excess in the urine (5-oxoprolinuria), can occur following paracetamol overdose, as well as in certain inborn errors of metabolism, causing high anion gap metabolic acidosis. Pyroglutamic acid is a natural humectant in skin, and part of its natural moisturizing factor (NMF). Pyroglutamic acid is also present as the N-terminal amino acid in orexin-A, a peptide involved in wakefulness, among other things.
Smith Kline and French, which entered into collaboration with Byk Gulden mid-1984, greatly assisted in determining criteria for further development. From 1985, the aim was to identify a compound with good stability at neutral pH, sustaining this higher level of stability down to pH 5 but being rapidly activateable at lower pHs, combined with a high level of H+/K+ ATPase inhibition. From the numerous already synthesized and tested compounds that fulfilled these criteria the most promising candidates were pantoprazole and its salt, pantoprazole sodium. In 1986 pantoprazole sodium sesquihydrate was synthesized and from 1987 onwards the development of pantoprazole was switched to the sodium salt which is more stable and has better compatibility with other excipients used in the drug formulation. Pantoprazole was identified after nearly seven years of research and registered for clinical use after a further seven years of development, and finally reached its first market in 1994 in Germany. During the course of the studies on pantoprazole, more than 650 PPIs had been synthesized and evaluated. Pantoprazole obtained high selection criteria in its development process — especially concerning the favorable low potential for interaction with other drugs. Good solubility of pantoprazole and a very high solution stability allowed it to become the first marketed PPI for intravenous use in critical care patients.
=== Carcinogens === Soy sauce may contain ethyl carbamate, a Group 2A carcinogen. In 2001, the United Kingdom Food Standards Agency found in testing various soy sauces manufactured in mainland China, Taiwan, Hong Kong, and Thailand (made from hydrolyzed soy protein, rather than being naturally fermented) that 22% of tested samples contained a chemical carcinogen named 3-MCPD (3-monochloropropane-1,2-diol) at levels considerably higher than those deemed safe by the EU. About two-thirds of these samples also contained a second carcinogenic chemical named 1,3-DCP (1,3-dichloropropane-2-ol) which experts advise should not be present at any levels in food. Both chemicals have the potential to cause cancer, and the Agency recommended that the affected products be withdrawn from shelves and avoided. The same carcinogens were found in soy sauces manufactured in Vietnam, causing a food scare in 2007. In Canada, the Canadian Cancer Society writes,
Sources: en.wikipedia.org
An advantage of the bacterial one-hybrid system over the yeast one-hybrid system (Y1H) lies in the higher transformation efficiency of plasmids into bacteria which allows for more complex “prey” libraries to be examined.
However, by 2025, relations had worsened, with US vice president JD Vance in February scolding "flimsy suspicions" and "enormous pressure from its continental neighbours" for causing the annulment of the 2024 Romanian presidential election in which Călin Georgescu won the first round. Relations with Moldova are a special case given that the two countries share the same language and a common history. A movement for unification of Moldova and Romania appeared in the early 1990s after both countries achieved emancipation from communist rule but lost ground in the mid-1990s when a new Moldovan government pursued an agenda towards preserving a Moldovan republic independent of Romania. After the 2009 protests in Moldova and the subsequent removal of Communists from power, relations between the two countries have improved considerably.
Myomesin plays an important role in the structure of sarcomeres. They are found in the M-band region of the sarcomere, between the thick filaments (myosin). Its main purpose in this setting is to provide structural integrity by linking the antiparallel myosin fibers and titin filaments which are connected to the Z-discs. These myosin filaments form a hexagonal lattice with titin and myomesin. This shape allows the M-band to withstand large conformational changes during muscle contraction and return to their original shape upon relaxation. Since the Z-disc region of the sarcomere is very stiff and unable to bend for contraction, the elastic activity of myomesin in the M-band is what makes muscle contraction possible as it acts as a molecular spring.
In the following decade, Gonzalo Arango founded the movement of "nothingness" in response to the violence of the time; he was influenced by nihilism, existentialism, and the thought of another great Colombian writer: Fernando González Ochoa. During the boom in Latin American literature, successful writers emerged, led by Nobel laureate Gabriel García Márquez and his magnum opus, One Hundred Years of Solitude, Eduardo Caballero Calderón, Manuel Mejía Vallejo, and Álvaro Mutis, a writer who was awarded the Cervantes Prize and the Prince of Asturias Award for Letters.
20 June – BBC One airs a Question Time election special featuring the leaders of the UK's four main political parties. Sunak says he is "incredibly angry" to learn of allegations that members of his party have betted on the date of the election, and that he will "boot out" anyone found to have broken the law. Scottish Parliament authorities have launched an investigation into the potential misuse of expenses to buy postage stamps by members of the SNP in order to send letters to voters. The Alliance Party launches its general election manifesto, with plans including reform of the devolved government at Stormont, and ringfencing funding for integrated eductation. 21 June – Nigel Farage tells the BBC that he believes the Russian invasion of Ukraine to have been precipitated by the West's eastward expansion of NATO and the European Union, but that the war itself is Vladimir Putin's fault. BBC Wales airs a televised election debate featuring Vaughan Gething (Labour), Jane Dodds (Liberal Democrat), Rhun ap Iorwerth (Plaid Cymru) and David TC Davies (Conservative). 22 June – BBC News publishes a list of eight Reform UK candidates who have made a wide range of offensive online posts about women between 2011 and 2023. Following criticism from other party leaders over his comments about Putin, Nigel Farage pens an op-ed in The Telegraph in which he says he has never been an "apologist or supporter" of Putin, but that "if you poke the Russian bear with a stick, don't be surprised if he responds".
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.