Semax comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-09-04. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
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 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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
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 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.
Semax 是一种人工合成的七肽，氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro，单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物，但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly，Semax 替换了中间两个残基，并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
Multiple synthetic studies directed towards ptaquilosin 11 have been reported since 1989. In 1994, Padwa and co-workers described the synthesis of the core skeleton of ptaquilosin by a highly convergent approach. In 1995, Cossy and co-workers reported novel routes to the racemic and optically active ptaquilosin skeleton. Their properly functionalized tricyclic compound would be of great utility for the synthesis of 11.
Marcus (1948), cardiologist and professor at University of Arizona Medical Center Frederick Reif (1948), professor of physics and psychology at Carnegie Mellon University, recipient of the 1994 Robert A. Millikan Award Robert Neil Butler (1949), president of the International Longevity Center and winner of the Pulitzer Prize for General Nonfiction William Chinowsky (1949), astrophysicist and professor at the University of California, San Diego Edgar Housepian (1949), neurosurgeon, co-founder of the Fund for Armenian Relief Benjamin Widom (1949), professor of chemistry at Cornell University; recipient of the Boltzmann Medal in 1998 Noel Corngold (1950), physicist at California Institute of Technology Edwin Kessler (1950), first director of the National Severe Storms Laboratory Gerald Weissmann (1950), cell biologist, liposome inventor, essayist Arthur H. Westing (1950), ecologist and researcher at Stockholm International Peace Research Institute Leon Cooper (1951), winner of the Nobel Prize in Physics in 1972 Richard A. Gardner (1952), psychiatrist known for researching Parental alienation syndrome Edgar Haber (1952), former president of Bristol-Myers Squibb and professor at Harvard Medical School Donald E.
Legal age (18+ years) High school diploma or equivalent State-approved training Successful completion of certification exam Medical laboratory assistants are required to have good analytical abilities and keen attention to detail. They must be able to work under pressure and display manual dexterity. Because they work with minute substances and technical equipment, good vision and computer skills are mandatory.
Cleavage of proteins is an irreversible post-translational modification carried out by enzymes known as proteases. These proteases are often highly specific and cause hydrolysis of a limited number of peptide bonds within the target protein. The resulting shortened protein has an altered polypeptide chain with different amino acids at the start and end of the chain. This post-translational modification often alters the protein's function; the protein can be inactivated or activated by the cleavage and can display new biological activities.
Microneedles are constructed through various methods, usually involving photolithographic processes or micromolding. These methods involve etching microscopic structure into resin or silicon in order to cast microneedles. Microneedles are made from a variety of material ranging from silicon, titanium, stainless steel, and polymers. A variety of MNs types (solid, hollow, coated, hydrogel) has been developed to possess different functions. Some microneedles are made of a drug to be delivered to the body but are shaped into a needle so they will penetrate the skin. The microneedles range in size, shape, and function but are all used as an alternative to other delivery methods like the conventional hypodermic needle or other injection apparatus. Stimuli-responsive microneedles are advanced devices that respond to environmental triggers such as temperature, pH, or light to release therapeutic agents. The research on MNs has led to improvements in different aspects, including instruments and techniques, yet adverse events are possible in MNs users.
Sources: en.wikipedia.org
=== Of its classification === Classification of OI has also evolved as scientific understanding of it has improved. Before the advent of modern genetic testing, OI was classified in two broad groups: osteogenesis imperfecta congenita, and osteogenesis imperfecta tarda, a division first proposed by the German physician E. Looser in 1906. Congenita was used to describe the modern clinical types II, III, and some cases of IV, where upon birth the condition was obvious, either due to bowing of the limbs or due to fractures sustained in utero. Tarda was used to classify the modern OI type I and some cases of type IV, where the inherent fragility of the bones did not become clear until long after birth. The idea that these "late" and "prenatal" forms were manifestations of the same disorder was first proposed in 1897 by Martin Benno Schmidt; by the 1950s this fact was well accepted. The modern system of four types (I, II, III, IV), meanwhile, were introduced in a paper by David Sillence, Alison Senn, and David Danks in the Journal of Medical Genetics in 1979, and have since become standard terms among doctors, patients, and researchers. The modern genetic types, (those with numbers greater than IV,) have come into use as more and more recessively inherited forms of OI have been discovered since the discovery of the first one by Roy Morello et al. in 2006.
The analogous Xe complex, with an infrared signal at 1943 cm−1, was more stable and could be observed at −30 °C (243 K) in pressurized liquid Xe. The highly reactive and transient Cp*Rh(CO) species believed to form upon photolysis also coordinates to and inserts into the C–H bonds of cyclohexane and other alkanes (R–H) under these conditions to give alkane σ-complexes Cp*Rh(CO)(R–H) and rhodium(III) alkyl complexes Cp*Rh(CO)(R)(H) upon oxidative addition.
=== Predators === Newborn rattlesnakes are heavily preyed upon by a variety of species, including cats, ravens, crows, roadrunners, raccoons, opossums, skunks, coyotes, weasels, whipsnakes, kingsnakes, and racers. Young of the smaller crotaline species are frequently killed and eaten by small predatory birds, such as jays, kingfishers, and shrikes. Some species of ants in the genus Formica are known to prey upon neonates, and Solenopsis invicta (fire ants) likely do, as well. On occasion, hungry adult rattlesnakes cannibalize neonates. The small proportion (often as few as 20%) of rattlesnakes that make it to their second year are heavily preyed upon by a variety of larger predators, including coyotes, eagles, hawks, owls, falcons, feral pigs, badgers, indigo snakes, and kingsnakes. The common kingsnake (Lampropeltis getula), a constrictor, is immune to the venom of rattlesnakes and other vipers, and rattlesnakes form part of its natural diet. Rattlesnakes sense kingsnakes' presence by their odor. When they realize a kingsnake is nearby, they begin enacting a set of defensive postures known as "body bridging". Unlike its normal erect and coiled defensive-striking posture, the rattlesnake keeps its head low to the ground in an attempt to prevent the kingsnake from gaining a hold on it (the head being the first part of the rattlesnake to be ingested). The rattlesnake jerks its body about, while bridging its back upwards, forming an elevated coil that faces the kingsnake. The elevated coil is used to strike the attacker, and is also used to shield the head from the kingsnake.
==== Initial campaigns (October–December 1932) ==== Liu Wenhui was taken off-guard by the sudden war; in contrast, Liu Xiang had developed a strategy of cutting his uncle's supply lines. Liu Xiang's forces would first attack Luzhou in a combined arms offensive featuring his army, navy, and aviation, capturing the city. After the loss of Luzhou, an uprising broke out in Yibin against the rule of Liu Wenhui and his extractive tax collector and brother Liu Wencai. Liu Wencai took advantage of the chaos gripping the city to loot around 1.4 million silver dollars, even taking artifacts from the Luzhou Fuzhou Hall. Liu Wencai then escaped, disguised as a foreigner, ending his rule of Yibin. Thus, already caught off-balance, Liu Wenhui lost two of his most important cities at the very start of the war. Liu Xiang's army then began advancing towards Leshan. In November, Liu Wenhui would end up antagonizing the other Baoding warlords by attacking Tian Songyao's forces in Chengdu. The ensuing urban warfare caused over 20,000 casualties and 27,000 refugees, leading to both warlords losing much of their popular support. Deng Xihou, the third Baoding warlord, attempted to mediate the conflict, but with no success. Although Tian Songyao had been defeated by December and even offered to retire, his subordinates refused to let him step down. In the end, a ceasefire was reached and Tian remained in Chengdu, causing no gain for Liu Wenhui, who had departed for Meishan to set up his headquarters.
Sources: en.wikipedia.org
=== Coenzymes === Coenzymes are small organic molecules that can be loosely or tightly bound to an enzyme. Coenzymes transport chemical groups from one enzyme to another. Examples include NADH, NADPH and adenosine triphosphate (ATP). Some coenzymes, such as flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), thiamine pyrophosphate (TPP), and tetrahydrofolate (THF), are derived from vitamins. These coenzymes cannot be synthesized by the body de novo and closely related compounds (vitamins) must be acquired from the diet. The chemical groups carried include:
The study showed that MMP-3 accomplishes this damage by degrading claudin-5, occludin, and ZO-1 (another tight junction protein), similar to how MMP-3 damages the BBB. The increase in blood-brain barrier and blood-spinal cord barrier permeability allows for more neutrophils to infiltrate the brain and spinal cord at the site of inflammation. Neutrophils carry MMP-9., which has also been shown to degrade occludin. This leads to further disruption of the BBB and BSCB
IAP is also recommended for women with intrapartum risk factors if their GBS carrier status is not known at the time of delivery, for women with GBS bacteriuria during their pregnancy, and for women who have had an infant with EOD previously. The risk-based approach for IAP is, in general, less effective than the culture-based approach because, in most cases, EOD develops among newborns, who are born to mothers without risk factors. In 2010, the Centers for Disease Control and Prevention (CDC), in collaboration with several professional groups, issued its revised GBS prevention guidelines. In 2018, the task of revising and updating the GBS prophylaxis guidelines was transferred from the CDC to American College of Obstetricians and Gynecologists (ACOG), the American Academy of Pediatrics, and to the American Society for Microbiology. The ACOG committee issued an update document on Prevention of Group B Streptococcal Early-Onset Disease in Newborns in 2019. This document does not introduce important changes from the CDC guidelines. The key measures necessary to prevent neonatal GBS early-onset disease continue to be universal prenatal screening by culture of GBS from swabs collected from the lower vagina and rectum, correct collection and microbiological processing of samples, and proper implementation of intrapartum antibiotic prophylaxis. The ACOG now recommends performing universal GBS screening between 36 and 37 weeks of gestation.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
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.