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 2026-06-23 and is reviewed periodically as new material appears.
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.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
| 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 |
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.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Lymph node enlargement or swelling is known as lymphadenopathy. Swelling may be due to many causes, including infections, tumors, autoimmune disease, drug reactions, diseases such as amyloidosis and sarcoidosis, or because of lymphoma or leukemia. Depending on the cause, swelling may be painful, particularly if the expansion is rapid and due to an infection or inflammation. Lymph node enlargement may be localized to an area, which might suggest a local source of infection or a tumour in that area that has spread to the lymph node. It may also be generalized, which might suggest infection, connective tissue or autoimmune disease, or a malignancy of blood cells such as a lymphoma or leukemia. Rarely, depending on location, lymph node enlargement may cause problems such as difficulty breathing, or compression of a blood vessel (for example, superior vena cava obstruction). Enlarged lymph nodes might be felt as part of a medical examination, or found on medical imaging. Features of the medical history may point to the cause, such as the speed of onset of swelling, pain, and other constitutional symptoms such as fevers or weight loss. For example, a tumour of the breast may result in swelling of the lymph nodes under the arms and weight loss and night sweats may suggest a malignancy such as lymphoma. In addition to a medical exam by a medical practitioner, medical tests may include blood tests and scans may be needed to further examine the cause. A biopsy of a lymph node may also be needed.
Myostatin inhibitors are a class of drugs that work by blocking the effect of myostatin, which inhibits muscle growth. In animal models and limited human studies, myostatin inhibitors have increased muscle size. They are being developed to treat obesity, sarcopenia, muscular dystrophy, and other illnesses.
== Pathophysiology == When ingested, hypoglycin A is metabolized to produce methylenecyclopropylacetic acid (MCPA). MCPA acts to inhibit the beta-oxidation of fatty acids in two ways. First, it interferes with the transport of long-chain fatty acids into the mitochondria by forming ester linkages with carnitine and coenzyme A (CoA). Also, it inhibits acyl-CoA dehydrogenases, so that only unsaturated fatty acids can be fully oxidized. Fatty acids accumulate in the liver in a microvesicular pattern that can be seen on biopsy. In the absence of fatty acid metabolism, the body becomes dependent on glucose and glycogen for energy. Octreotide can be used to reduce the secretion of insulin by the pancreas, thereby preventing severe hypoglycemia. Inhibition of beta-oxidation of fatty acids, however, also depletes nicotinamide adenine dinucleotide (NADH) and acetyl CoA—the latter an activator of pyruvate carboxylase—inhibiting gluconeogenesis. Once the liver glycogen stores are depleted, the body cannot synthesize glucose, and severe hypoglycemia results. Initial symptoms appear after about four hours, and deaths have been reported from 12 to 48 hours following consumption. Supportive care involves carefully metered IV glucose infusion and fluid/electrolyte replacement; mortality was 80% before glucose infusion was introduced in 1954. A similar outbreak of lethal hypoglycemic encephalopathy has been linked to the consumption of lychee fruit in Muzaffarpur, India.
Sources: en.wikipedia.org
In 1858, William Parker Foulke discovered the first known American dinosaur in marl pits in the small town of Haddonfield, New Jersey. (Although fossils had been found before, their nature had not been correctly discerned.) The creature was named Hadrosaurus foulkii. It was an extremely important find: Hadrosaurus was one of the first nearly complete dinosaur skeletons found (the first was in 1834, in Maidstone, England), and it was clearly a bipedal creature. This was a revolutionary discovery as, until that point, most scientists had assumed dinosaurs walked on four feet, like other lizards. Foulke's discoveries sparked a wave of interests in dinosaurs in the United States, known as Dinosaur Mania. Dinosaur mania was exemplified by the fierce rivalry between Edward Drinker Cope and Othniel Charles Marsh, both of whom raced to be the first to find new dinosaurs in what came to be known as the Bone Wars. This fight between the two scientists lasted for over 30 years, ending in 1897 when Cope died after spending his entire fortune on the dinosaur hunt. Many valuable dinosaur specimens were damaged or destroyed due to the pair's rough methods: for example, their diggers often used dynamite to unearth bones. Modern paleontologists would find such methods crude and unacceptable, since blasting easily destroys fossil and stratigraphic evidence. Despite their unrefined methods, the contributions of Cope and Marsh to paleontology were vast: Marsh unearthed 86 new species of dinosaur and Cope discovered 56, a total of 142 new species.
A sector-type mass analyzer uses a static electric and/or magnetic field to control the path of the ion beam. The most common type uses a magnetic field. In a simplified case, the field is a constant field
Wadi al-Taym is named after the Arab tribe of Taym Allat (later Taym-Allah) ibn Tha'laba. The Taym-Allat entered the Euphrates Valley and adopted Christianity in the pre-Islamic period before ultimately embracing Islam after the 7th-century Muslim conquests. A small proportion of the tribe took up abode in the Wadi al-Taym at some point during the first centuries of Muslim rule. The Taym Allah, and the largely Christian, core tribes of the Lahazim in general, appear to have fought against the Muslim conquests of eastern Arabia in the Ridda wars (632–633) and the lower Euphrates in modern Iraq afterward. They embraced Monophysite Christianity, like many Bakrites, before the advent of Islam in the 620s–630s. This valley became one of the first places where the heterodox Druze faith, which branched out of Isma'ili Shia Islam, took root in the 11th century. The Wadi al-Taym was the first area where the Druze appeared in the historical record under the name "Druze". According to many of the genealogical traditions of the Druze feudal families, the feudal Druze clans claimed descent from Arab tribes originally based in eastern Arabia and which entered Syria after periods of settlement in the Euphrates Valley. According to the historian Nejla Abu-Izzedin, "ethnically", the "Wadi al-Taym has been authoritatively stated to be one of the most Arab regions of [geographical] Syria". The area was one of the two most important centers of Druze missionary activity in the 11th century. Wadi al-Taym is generally considered the "birthplace of the Druze faith".
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.
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.