If you have been reading about nootropic and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-01-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
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。
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。
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
== Catalytic mechanism == The accepted catalytic mechanism, called the “ping-pong mechanism,” consists of four major stages. The first stage is the oxidation of the substrate by the double-redox center. After the hydroxyl group of substrate alcohol occupies the solvent coordination site, the hydroxyl group is deprotonated by Tyr495, followed by the release of Tyr495. This step makes the alcohol more prone to oxidation. The proton on the carbon to which the hydroxyl group used to be attached is then transferred to Tyr272 (serving as the hydrogen acceptor), coupled with the oxidation of the substrate. One electron goes to the radical ligand, the other electron goes to the copper(II) center, which is then reduced to copper(I) as a result. Meanwhile, Tyr272 radical is also reduced. The proton subtraction step is rate determining and stereospecific since only the pro-S hydrogen on the alcohol carbon is removed (supported by studies of its kinetic isotope effect). The overall result of stage 1 is the removal of two hydrogen atoms and the removal two electrons from the substrate, of which the order is unclear, however. The second stage is the release of oxidized substrate (aldehyde in this case) and the coordination of dioxygen at the substrate coordination site. In the third stage, dioxygen is rapidly reduced by copper(I) to form superoxide. The superoxide is a reactive species that subtracts the proton and an electron from the Tyr272 and re-forms the tyrosine radical. In the fourth stage, the hydroperoxide deprotonates Tyr496 and is released as H2O2.
Marxism–Leninism has been broadly criticized, particularly in its Stalinist and Maoist variants, across the political spectrum. Most communist states have been regarded as authoritarian, and some of them have been accused of being totalitarian, especially the Soviet Union under Joseph Stalin, China under Mao Zedong, North Korea under Kim Il Sung, and Romania under Nicolae Ceaușescu. Rival ideologies were persecuted, including dissident leftists, and most elections had only one candidate. According to Daniel Gray, Silvio Pons, and David Martin Walker, Marxist–Leninist regimes have carried out killings and political repression of dissidents and social classes ("enemies of the people"), such as the Red Terror and Great Purge in the Soviet Union and the Campaign to Suppress Counterrevolutionaries in China, partly as a result of Marxist–Leninist ideology. According to Gray, they were justified as a means of maintaining "proletarian power". According to Gray and Walker, political dissidents were deemed to be "distorting the true path to communism". According to Pons, repression of social groups was deemed a necessary part of class struggle against the "exploiting classes". In addition, Robert Service stated that mass religious persecution, such as in the Soviet Union and in China, was motivated by Marxist–Leninist atheism.
where R is the ratio of the actual area of the surface to the observed area of a surface and θ is the Young's contact angle as defined for an ideal surface. See Wetting. Based on the physical modification of the surface, an antiviral surface can be designed by decorating micropillars on the surface.
Humanitarian agencies in Yemen operate in an environment shaped by military, administrative and political constraints imposed by the different sides of the conflict. At sea, naval controls, inspection regimes and port restrictions have delayed or limited the arrival of food, fuel and medical supplies, creating recurrent logistical challenges. In territories controlled by the Houthis instead, aid efforts have also been victim of a dense bureaucracy, as the creation of the Supreme Council for the Management and Coordination of Humanitarian Affairs (SCMCHA) gave the Houthis decisional power over project approvals, staff movement, and local partnerships among many other things. Reports from donors and humanitarian organizations describe then diversion of assistance, pressure to channel funds and contracts through Houthi-linked entities, black-market resale of aid and attempts to impose additional taxes on humanitarian programmes, all of which have delayed operations and increased their cost. Donor governments have debated imposing stricter conditions or suspending some forms of assistance in response to these actions, but such measures have been pursued cautiously because of concerns that a reduction in aid would primarily affect civilians who depend on it.
Sources: en.wikipedia.org
In 2011 in Nakhon Ratchasima, Thailand, truckloads of rotten chicken were treated with formaldehyde for sale in which "a large network", including 11 slaughterhouses run by a criminal gang, were implicated. In 2012, 1 billion rupiah (almost US$100,000) of fish imported from Pakistan to Batam, Indonesia, were found laced with formaldehyde. Formalin contamination of foods has been reported in Bangladesh, with stores and supermarkets selling fruits, fishes, and vegetables that have been treated with formalin to keep them fresh. However, in 2015, a Formalin Control Bill was passed in the Parliament of Bangladesh with a provision of life-term imprisonment as the maximum punishment as well as a maximum fine of 2,000,000 BDT but not less than 500,000 BDT for importing, producing, or hoarding formalin without a license. In the early 1900s, formaldehyde was frequently added by US milk plants to milk bottles as a method of pasteurization due to the lack of knowledge and concern regarding formaldehyde's toxicity. Formaldehyde was one of the chemicals used in 19th-century industrialized food production that was investigated by Dr. Harvey W. Wiley with his famous "Poison Squad" as part of the US Department of Agriculture. This led to the 1906 Pure Food and Drug Act, a landmark event in the early history of food regulation in the United States.
== Clinical significance == Truncation mutations in MYBPC3 stand as the primary cause of hypertrophic cardiomyopathy (HCM). To date, roughly 350 mutations in MYBPC3 have been identified, and in large part, the mutations result in protein truncation, shifts in reading frames, and premature termination codons. Genetic studies have revealed significant overlap between genotypes and phenotypes as MYBPC3 mutations can lead to various forms of cardiomyopathies, such as dilated cardiomyopathy and left ventricular noncompaction cardiomyopathy. In patients with isolated or familial cases of dilated cardiomyopathy, MYBPC3 mutations represented the second highest number of known mutations. Furthermore, a 25-bp intronic MYBPC3 deletion leading to protein truncation is present in 4% of the population in South India and is associated with a higher risk to develop heart failure. Founder MYBPC3 mutations have been reported in Iceland, Italy, The Netherlands, Japan, France and Finland, where they represent a large percentage of cases with hypertrophic cardiomyopathy. All of them are truncating mutations, resulting in a shorter protein, lacking the regulatory phosphorylatable M motif and/or major binding domains to other sarcomeric proteins. A body of evidence indicates that patients with more than one mutation often develop a more severe phenotype, and a significant fraction of childhood-onset hypertrophic cardiomyopathy (14%) is caused by compound genetic variants. This suggests that a gene-dosage effect might be responsible for manifestations at a younger age.
Charles Herbert Best (February 27, 1899 – March 31, 1978), was an American-Canadian medical scientist and one of the co-discoverers of insulin with Frederick Banting. He served as the chair of the Banting and Best Department of Medical Research at the University of Toronto and was further involved in research concerning choline and heparin.
Kuban Cossacks are Cossacks who live in the Kuban region of Russia. Although many Cossack groups came to inhabit the Western North Caucasus, most of the Kuban Cossacks are descendants of the Black Sea Cossack Host (originally the Zaporozhian Cossacks), and the Caucasus Line Cossack Host. During the Russian Civil War, Kuban Cossacks established their own state, the Kuban People's Republic. They attempted to form a federal union with Ukraine People's Republic, but it was defeated by the White Army forces undert Anton Denikin, and eventually Kuban was overcome by the Bolsheviks.
== Eukaryotic analogue == The complexity in bacterial responses appears to be in the number of proteins induced by oxidative stress. In mammalian cells, the number of proteins induced is small but the regulatory pathways are highly complex. The inducers of oxidative stress responses in bacteria appear to be either the oxidant itself or interaction of the oxidant with a cell component. Most mammalian cells exist in an environment where the oxygen concentration is constant, thus responses are not directly stimulated by oxidants. Rather, cytokines such as tumor necrosis factor, interleukin-1 or bacterial polysaccharides induce SOD synthesis and multigene responses. Recent work shows that superoxide is a strong tumor promoter that works by activation and induction growth-competence related gene products. Other factors involved in the antioxidant gene expression include an induction of calmodulin kinase by increase in Ca2+ concentrations. E. coli cells have revealed similarities to the aging process of higher organisms. The similarities include increased oxidation of cellular constituents and its target specificity, the role of antioxidants and oxygen tension in determining life span, and an apparent trade-off between activities related to reproduction and survival.
Sources: en.wikipedia.org
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.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。