A practical reference on ACTH fragment: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-01-19. Anything still debated is marked as such rather than presented as settled.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
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.
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.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
=== Seizures === For drug-resistant focal epilepsy, pregabalin is useful as an add-on therapy to other treatments. Its use alone is less effective than some other seizure medications. It is unclear how it compares to gabapentin for this use.
Edwin Haslam (1993). Shikimic Acid: Metabolism and Metabolites (1st ed.). ISBN 0471939994. Brown, Stewart A.; Neish, A. C. (1955). "Shikimic Acid as a Precursor in Lignin Biosynthesis". Nature. 175 (4459): 688–689. Bibcode:1955Natur.175..688B. doi:10.1038/175688a0. ISSN 0028-0836. PMID 14370198. S2CID 4273320. Weinstein, L. H.; Porter, C. A.; Laurencot, H. J. (1962). "Role of the Shikimic Acid Pathway in the Formation of Tryptophan in Higher Plants : Evidence for an Alternative Pathway in the Bean". Nature. 194 (4824): 205–206. Bibcode:1962Natur.194..205W. doi:10.1038/194205a0. ISSN 0028-0836. S2CID 4160308. Wilson, D J; Patton, S; Florova, G; Hale, V; Reynolds, K A (1998). "The shikimic acid pathway and polyketide biosynthesis". Journal of Industrial Microbiology and Biotechnology. 20 (5): 299–303. doi:10.1038/sj.jim.2900527. ISSN 1367-5435. S2CID 41117722.
==== Phenylpiperazines/quinolinones/benzoxazinones ==== Aripiprazole (Abilify) - Partial agonist at the D2 receptor. Considered the prototypical third-generation antipsychotic. Aripiprazole lauroxil (Abilify Maintena) – Long-acting version of aripiprazole for injection. Brexpiprazole (Rexulti) – Partial agonist of the D2 receptor. Successor of aripiprazole. Brilaroxazine – A D2/3/4 and 5-HT1A partial agonist and 5-HT2A/2B/7 antagonist Cariprazine (Vraylar, Reagila) – A D3-preferring D2/3 partial agonist.
Simple diatomic molecules have only one bond and only one vibrational band. If the molecule is symmetrical, e.g. N2, the band is not observed in the IR spectrum, but only in the Raman spectrum. Asymmetrical diatomic molecules, e.g. carbon monoxide (CO), absorb in the IR spectrum. More complex molecules have many bonds, and their vibrational spectra are correspondingly more complex, i.e. big molecules have many peaks in their IR spectra. The atoms in a CH2X2 group, commonly found in organic compounds and where X can represent any other atom, can vibrate in nine different ways. Six of these vibrations involve only the CH2 portion: two stretching modes (ν): symmetric (νs) and antisymmetric (νas); and four bending modes: scissoring (δ), rocking (ρ), wagging (ω) and twisting (τ), as shown below. Structures that do not have the two additional X groups attached have fewer modes because some modes are defined by specific relationships to those other attached groups. For example, in water, the rocking, wagging, and twisting modes do not exist because these types of motions of the H atoms represent simple rotation of the whole molecule rather than vibrations within it. In case of more complex molecules, out-of-plane (γ) vibrational modes can be also present.
For moderate to severe sleep apnea, the most common treatment is the use of a continuous positive airway pressure (CPAP) or automatic positive airway pressure (APAP) device. These splint the person's airway open during sleep by means of pressurized air. The person typically wears a facial mask connected by a flexible tube to a small bedside CPAP machine. Although CPAP therapy is effective in reducing apneas and less expensive than other treatments, some people find it uncomfortable. Some complain of feeling trapped, having chest discomfort, and skin or nose irritation. Other side effects may include dry mouth, dry nose, nosebleeds, sore lips and gums. Whether or not it decreases the risk of death or heart disease is controversial with some reviews finding benefit and others not. This variation across studies might be driven by low rates of compliance—analyses of those who use CPAP for at least four hours a night suggests a decrease in cardiovascular events.
Sources: en.wikipedia.org
== Clinical significance == Progression of epithelial cancer often relies on deep and regional lymph node invasion. The lamina propria, being one of the barriers to the submucosa, is an area where epithelial cancer invasion is of significance since lymphatic invasion is an independent predictor of lymph node metastasis, especially in gastric cancer. As soon as the tumors breach the basement membrane and reach the lamina propria, they are exposed to lymphatics which may increase the rate of metastasis and cancer progression. Deeper invasion into the submucosa will increase the exposure to lymphatics. Long-standing inflammation is a risk factor for the development of cancer. The lamina propria macrophages when under much stress release pro-inflammatory signals that may lead to increased probability of developing cancer. An example of this is the overactivation of the IL-6/STAT3 pathway, which has been linked to colitis-associated cancer.
Promotion of the Mediterranean diets among the obese may lower the risk of heart disease. Decreased intake of sweet drinks is also related to weight-loss. Success rates of long-term weight loss maintenance with lifestyle changes are low, ranging from 2–20%. Dietary and lifestyle changes are effective in limiting excessive weight gain in pregnancy and improve outcomes for both the mother and the child. Intensive behavioral counseling is recommended in those who are both obese and have other risk factors for heart disease.
The Riksdag (Swedish: [ˈrɪ̌ksdɑːɡ] or [ˈrɪ̌ksda], lit. 'diet of the realm') is the parliament and the supreme decision-making body of the Kingdom of Sweden. Since 1971, the Riksdag has been a unicameral parliament with 349 members (riksdagsledamöter), elected proportionally and serving, since 1994, fixed four-year terms. The 2026 Swedish general election is the most recent general election. The constitutional mandates of the Riksdag are enumerated in the Instrument of Government (Regeringsformen), and its internal workings are specified in greater detail in the Riksdag Act (Riksdagsordningen). The seat of the Riksdag is at Parliament House (Riksdagshuset), on the island of Helgeandsholmen in central Stockholm, in Gamla stan, the old town of Stockholm. The Riksdag has its institutional roots in the feudal Riksdag of the Estates, traditionally thought to have first assembled in Arboga in 1435. In 1866, following reforms of the 1809 Instrument of Government, that body was transformed into a bicameral legislature with an upper chamber (första kammaren) and a lower chamber (andra kammaren).
Sulfur, also spelled as sulphur, is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with the chemical formula S8. Elemental sulfur is a bright yellow, crystalline solid at room temperature. Sulfur is the tenth most abundant element by mass in the universe and the fifth most common on Earth. Though sometimes found in pure, native form, sulfur on Earth usually occurs as sulfide and sulfate minerals. Being abundant in native form, sulfur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt. Historically and in literature sulfur is also called brimstone, which means "burning stone". Almost all elemental sulfur is produced as a byproduct of removing sulfur-containing contaminants from natural gas and petroleum. The greatest commercial use of the element is the production of sulfuric acid for sulfate and phosphate fertilizers, and other chemical processes. Sulfur is used in matches, insecticides, and fungicides. Many sulfur compounds are odoriferous, and the smells of odorized natural gas, skunk scent, bad breath, grapefruit, and garlic are due to organosulfur compounds. Hydrogen sulfide gives the characteristic odor to rotting eggs and other biological processes. Sulfur is an essential element for all life, almost always in the form of organosulfur compounds or metal sulfides.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.