ACTH(4–10) is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-02-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
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.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
GoldSrc (pronounced "gold source", formerly the Half-Life Engine) is a proprietary game engine developed by Valve. At its core, GoldSrc is a heavily modified version of id Software's Quake engine. It made its debut in 1998 with Half-Life and powered future games developed by or with oversight from Valve, including Half-Life's expansions, Day of Defeat and games in the Counter-Strike series. GoldSrc was succeeded by the Source engine with the releases of Half-Life: Source, Half-Life 2, and Counter-Strike: Source in 2004.
== Chemistry == Valproic acid is a branched short-chain fatty acid (SCFA) and the 2-n-propyl derivative of valeric acid (valerate; pentanoic acid; pentanoate). It is also a GABA analogue, or analogue of the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Other analogues of valproic acid include valproate pivoxil, valpromide, and valnoctamide.
The St. Augustine Monster is the name given to a large carcass, originally postulated to be the remains of a gigantic octopus, that washed ashore on the United States coast near St. Augustine, Florida in 1896. It is sometimes referred to as the Florida Monster or the St. Augustine Giant Octopus and is one of the earliest recorded examples of a globster. The species that the carcass supposedly represented has been assigned the binomial names Octopus giganteus (Latin for "giant octopus") and Otoctopus giganteus (Greek prefix: oton = "ear"; "giant-eared octopus"), although these are not valid under the rules of the ICZN. A 1995 analysis concluded that the St. Augustine Monster was a large mass of the collagenous matrix of whale blubber, likely from a sperm whale.
Sources: en.wikipedia.org
== Calcium-deficient hydroxyapatite == Calcium-deficient (non-stoichiometric) hydroxyapatite, Ca10−x(PO4)6−x(HPO4)x(OH)2−x (where x is between 0 and 1) has a Ca/P ratio between 1.67 and 1.5. The Ca/P ratio is often used in the discussion of calcium phosphate phases. Stoichiometric apatite Ca10(PO4)6(OH)2 has a Ca/P ratio of 10:6 normally expressed as 1.67. The non-stoichiometric phases have the hydroxyapatite structure with cation vacancies (Ca2+) and anion (OH−) vacancies. The sites occupied solely by phosphate anions in stoichiometric hydroxyapatite, are occupied by phosphate or hydrogen phosphate, HPO2−4, anions. These calcium-deficient phases can be prepared by precipitation from a mixture of calcium nitrate and diammonium phosphate with the desired Ca/P ratio, for example, to make a sample with a Ca/P ratio of 1.6:
== Chemical Protein Synthesis == Native chemical ligation of unprotected peptide segments is used to prepare the protein's polypeptide chain, which is then folded to form a protein molecule. In native chemical ligation, a peptide C-terminal thioester reacts with a second peptide that has a cysteine residue at its N-terminus, to give a product with a peptide bond at the ligation site. Multiple unprotected peptide segments can be linked in this way to give the full length polypeptide chain, which is folded to give the target protein molecule. Once the chemical synthesis of an L-protein is achieved, the D-protein enantiomer can be prepared using synthetic peptide building blocks made from D-amino acids and Gly. Convergent synthesis is most effective in preparing long polypeptide chains using synthetic peptide-hydrazides, where the hydrazide can be converted to a thioester for use in native chemical ligation. The hydrazide is stable to native chemical ligation reaction conditions, and can be converted in situ to a reactive peptide-thioester for the next native chemical ligation condensation reaction.
Carrie Buck was raped by a nephew of her adopted parents in Virginia at the age of 17. In an attempt to cover up the assault, her family committed her to the Lynchburg State Colony for Epileptics and Feebleminded. Soon later, the colony realized that Buck was pregnant with her assailant's child. At the colony, Dr. Albert Sidney Priddy examined Buck and deemed her to be unfit due to her feeblemindedness. Priddy recommended her for sterilization. This was brought to the courts in order to sanctify the sterilization order. Buck's biological mother was labeled as feebleminded, so Buck was used as "proof" that feeblemindedness was hereditary and sterilization was necessary for the common good. The Supreme Court voted 8-1 stating that being feebleminded led to promiscuity and sterilization was justified. Buck was then sterilized under the Virginia 1924 compulsory sterilization statue. The Supreme Court case of Buck v. Bell confirmed the constitutionality of sterilization of the feebleminded and "unfit". This case solidified that involuntary sterilization was not cruel or unusual punishment and it did not violate due process, but rather it helped the good of the country as a whole. Individual rights of reproduction were now able to be taken for the public good. Cases of involuntary sterilization rose significantly after this case in 1927.
Sources: en.wikipedia.org
The PLA is a component of the armed forces of China, which also includes the PAP, the reserves, and the militia. The armed forces are controlled by the CCP under the doctrine of "the Party commands the gun". The PLA and the PAP have the largest delegation in the National People's Congress (NPC), which are elected by servicemember election committees of top-level military subdivisions, including the PLA's theater commands and service branches. At the 14th National People's Congress; the joint delegation has 281 deputies—over 9% of the total—all of whom are CCP members.
Leukotriene C4 synthase is an enzyme that in humans is encoded by the LTC4S gene. The protein encoded by this gene, LTC4S (or glutathione S-transferase II) is an enzyme that converts leukotriene A4 and glutathione to create leukotriene C4. This is a member of MAPEG family of transmembrane proteins. A trimer of Leukotriene C4 synthase is localized on the outer nuclear membrane and endoplasmic reticulum, where it forms a complex with 5-Lipoxygenase-activating protein. This protein is remotely related to microsomal glutathione S-transferase.
Enzymes that use a metal in the active site are called "metallo-carboxypeptidases" (EC number 3.4.17). Other carboxypeptidases that use active site serine residues are called "serine carboxypeptidases" (EC number 3.4.16). Those that use an active site cysteine are called "cysteine carboxypeptidase" (or "thiol carboxypeptidases")(EC number 3.4.18). These names do not refer to the selectivity of the amino acid that is cleaved.
== Antiangiogenic antithrombin == Angiogenesis is a physiological process involving the growth of new blood vessels from pre-existing vessels. Under normal physiological conditions angiogenesis is tightly regulated and is controlled by a balance of angiogenic stimulators and angiogenic inhibitors. Tumor growth is dependent upon angiogenesis and during tumor development a sustained production of angiogenic stimulatory factors is required along with a reduction in the quantity of angiogenic inhibitory factors tumor cells produce. The cleaved and latent form of antithrombin potently inhibit angiogenesis and tumor growth in animal models. The prelatent form of antithrombin has been shown to inhibit angiogenesis in-vitro but to date has not been tested in experimental animal models.
Sources: en.wikipedia.org
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.