This is a working overview of Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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 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.
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.
| 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 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.
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.
Chocolate agar (CHOC) or chocolate blood agar (CBA) is a nonselective, enriched growth medium used for isolation of pathogenic bacteria. It is a variant of the blood agar plate, containing red blood cells that have been lysed by slowly heating to 80 °C. Chocolate agar is used for growing fastidious respiratory bacteria, such as Haemophilus influenzae and Neisseria meningitidis. In addition, some of these bacteria, most notably H. influenzae, need growth factors such as nicotinamide adenine dinucleotide (factor V or NAD) and hemin (factor X), which are inside red blood cells; thus, a prerequisite to growth for these bacteria is the presence of red blood cell lysates. The heat also inactivates enzymes which could otherwise degrade NAD. The agar is named for its color and contains no chocolate products.
The judicial branch is headed by four high courts, consisting of the Supreme Court which deals with penal and civil matters, the Council of State, which has special responsibility for administrative law and also provides legal advice to the executive, the Constitutional Court, responsible for assuring the integrity of the Colombian constitution, and the Superior Council of Judicature, responsible for auditing the judicial branch. Colombia operates a system of civil law, which since 1991 has been applied through an adversarial system. Despite a number of controversies, the democratic security policy has ensured that former President Álvaro Uribe remained popular among Colombian people, with his approval rating peaking at 76%, according to a poll in 2009. However, having served two terms, he was constitutionally barred from seeking re-election in 2010. In the run-off elections on 20 June 2010 the former Minister of Defense Juan Manuel Santos won with 69% of the vote against the second most popular candidate, Antanas Mockus. A second round was required since no candidate received over the 50% winning threshold of votes. Santos won re-election with nearly 51% of the vote in second-round elections on 15 June 2014, beating right-wing rival Óscar Iván Zuluaga, who won 45%. In 2018, Iván Duque won in the second round of the election with 54% of the vote, against 42% for his left-wing rival, Gustavo Petro. His term as Colombia's president ran for four years, beginning on 7 August 2018.
=== Lamellar keratoplasty === Lamellar keratoplasty encompasses several techniques which selectively replace diseased layers of the cornea while leaving healthy layers in place. The chief advantage is improved tectonic integrity of the eye. Disadvantages include the technically challenging nature of these procedures, which replace portions of a structure only 500 μm thick, and reduced optical performance of the donor/recipient interface compared to full-thickness keratoplasty.
Sources: en.wikipedia.org
Angiotensin II, endothelin-1, or phenylepinephrine cause HSP70 overexpression, which activates several molecular pathways, resulting in increased production of ROS, CRP, IL-10, TNF-alpha, and IL-6 These inflammatory signals interfere with the antioxidant machinery and results in rapid disease progression. HSP70 expression increases after the coronary bypass surgery. Exercise has a positive and protective impact on cardiovascular disorders and stimulates the increased production of chaperone protein, which is cardioprotective.
==== Carnivoran research ==== Evidence of impact of competition on diversification of North American and Eurasian carnivorans throughout the last 45 million years is presented by Porto & Quental (2026). A study on the mandibles of extant and extinct carnivorans, providing evidence of overall decoupling of evolution of mandible shape and function, but also possible evidence of modular dynamics in the evolution of mandible, with differences in the pace and correlation of evolution of different anatomical regions, is published by Sansalone et al. (2026). Bartolini-Lucenti et al. (2026) document new occurrences of carnivorans in the Pliocene strata from the Jradzor locality (Armenia), including Baranogale helbingi, Chasmaporthetes lunensis, Pliocrocuta perrieri and cf. Lynx sp., expanding known geographic and temporal ranges of the studied carnivorans. Orcutt et al. (2026) report the discovery of new carnivoran fossil material from the John Day Formation (Oregon, United States), including the first definitive records of Osbornodon sp. and Otarocyon sp. from the studied formation, as well as a possible fossil material of a large amphicyonine. Espinasa et al. (2026) study the composition of the Rancholabrean carnivoran assemblage from the Calera cave system (San Luis Potosí, Mexico), including a growth sequence of Smilodon fatalis. Díaz de León-Muñoz, Siliceo & Ferreira (2026) study the feeding behavior of Magericyon anceps, reporting evidence of resistance of its mandible to loads during hunting, but also evidence of an unexpectedly weak bite.
=== Classification of abdominal and pelvic structures === The structures in the abdomen are classified as intraperitoneal, mesoperitoneal, retroperitoneal or infraperitoneal depending on whether they are covered with visceral peritoneum and whether they are attached by mesenteries (mensentery, mesocolon).
Sources: en.wikipedia.org
Positive health of a person is defined as the ability to live long in good health without activity limitation. This implies the availability of mechanism in the body to thwart the ailments and to minimize their adverse effect if they strike. The concept has evolved over time and has seen significant changes.
== Amino-acid propensities == Different amino-acid sequences have different propensities for forming α-helical structure. Alanine, uncharged glutamate, leucine, charged arginine, methionine and charged lysine have especially high helix-forming propensities, whereas proline and glycine have poor helix-forming propensities. Proline either breaks or kinks a helix, both because it cannot donate an amide hydrogen bond (because it has none) and because its sidechain interferes sterically with the backbone of the preceding turn – inside a helix, which forces a bend of about 30° in the helix's axis. However, proline is often the first residue of a helix, presumably due to its structural rigidity. At the other extreme, glycine also tends to disrupt helices because its high conformational flexibility makes it entropically expensive to adopt the relatively constrained α-helical structure.
== See also == Trimethoxyamphetamine Substituted methoxyphenethylamine 2,4,5-Trimethoxyphenethylamine (2,4,5-TMPEA; 2C-O) 2,5-Dimethoxyamphetamine (2,5-DMA; DMA-4; DOH) 2,4-Dimethoxyamphetamine (2,4-DMA; DMA-3)
=== Pharmacodynamics === Several in vitro and in vivo studies have demonstrated that dihydroergocriptine is an effective anti-Parkinson drug, most likely exerting its effects as a potent agonist of D2 receptors. The Kd of DHEC is found to be around 5-8 nM at D2 receptors. Less certain is the contribution of its partial D1 receptor and D3 receptor agonist activity. DHEC has a lower affinity for D1 and D3 receptors (Kd is around 30 nM for both) than for D2 receptors. It is widely believed that dopamine receptor agonists demonstrate their antiparkinsonian effects by stimulating D2 receptors primarily, but other dopamine receptors, such as D1 and D3 may be involved. Remarkably, DHEC is said to not significantly interact with serotonergic and adrenergic receptors.
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.
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.