heptapeptide is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-01-02. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
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.
| Property | Value | Notes |
|---|---|---|
| 化学类别 | 合成七肽 | ACTH(4-10) 结构类似物 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | 单字母写作 MEHFPGP |
| 分子量 | 约 813.9 Da | 随确切形式和盐型略有变化 |
| 常见同义词 | ACTH(4-10) 类似物 | 俄语文献称 Семакс |
| 开发来源 | 俄罗斯 | 二十世纪八十年代 |
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.
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.
== Work == Ruhrarbeiter gegen den Faschismus Dokumentation über den Widerstand im Ruhrgebeit 1933–1945, Frankfurt am Main, 1976. Die Reihen fast geschlossen: Beiträge zur Geschichte des Alltags unterm Nationalsozialismus co-edited with Jürgen Reulecke & Adelheid Gräfin zu Castell-Rüdenhausen, Wuppertal: Hammer, 1981. Volksgenossen und Gemeinschaftsfremde: Anpassung, Ausmerze und Aufbegehren unter dem Nationalsozialismus Cologne: Bund Verlag, 1982, translated into English by Richard Deveson as Inside Nazi Germany: Conformity, Opposition and Racism in Everyday Life London: Batsford, 1987 ISBN 0-7134-5217-X. Die Weimarer Republik : Krisenjahre der Klassischen Moderne, Frankfurt am Main: Suhrkamp Verlag, 1987 translated into English as The Weimar Republic: the Crisis of Classical Modernity, New York : Hill and Wang, 1992 ISBN 0-8090-9674-9. “The Genesis of the `Final Solution’ from the Spirit of Science” pages 234-252 from Reevaluating the Third Reich edited by Thomas Childers and Jane Caplan, New York: Holmes & Meier, 1994 ISBN 0-8419-1178-9. The German original was published as "Die Genesis der 'Endlösung' aus dem Geist der Wissenschaft," in Max Webers Diagnose der Moderne, edited by Detlev Peukert (Göttingen: Vandenhoeck & Ruprecht, 1989), pages 102–21, ISBN 3-525-33562-8.
Singapore has a highly developed market economy, based historically on extended entrepôt trade. Along with Hong Kong, South Korea, and Taiwan, Singapore is one of the Four Asian Tigers, and has surpassed its peers in terms of Gross Domestic Product (GDP) per capita. Between 1965 and 1995, growth rates averaged around 6 per cent per annum, transforming the living standards of the population. The Singaporean economy is regarded as free, innovative, dynamic and business-friendly. For several years, Singapore has been one of the few countries with a AAA credit rating from the big three, and the only Asian country to achieve this rating. Singapore attracts a large amount of foreign investment as a result of its location, skilled workforce, low tax rates, advanced infrastructure and zero-tolerance against corruption. It was the world's 4th most competitive economy in 2023, according to the International Institute for Management Development's World Competitiveness Ranking of 64 countries, with the highest GDP (PPP) per capita. Roughly 44 per cent of the Singaporean workforce is made up of non-Singaporeans. Despite market freedom, Singapore's government operations have a significant stake in the economy, contributing 22% of the GDP. The city is a popular location for conferences and events.
== Research == The exact mechanism for this protein is currently not known, but efforts continue to isolate activated protein C mutants that lack anticoagulant properties for potential therapeutic use.
Sources: en.wikipedia.org
==== Synthesis of crown ethers ==== A series of polynomial heterocyclic compounds, known as crown ethers, can be synthesized with ethylene oxide. One method is the cationic cyclopolymerization of ethylene oxide, limiting the size of the formed cycle:
Efraim Halevy (Hebrew: אפרים הלוי; born in London, 2 December 1934); Israeli intelligence expert and diplomat; was director of Mossad and 3rd head of Israeli National Security Council; author of Man in the Shadows, covering Middle Eastern history since the late 1980s; nephew of Sir Isaiah Berlin; has written for The Washington Post, Jerusalem Post, Times of Israel, Haaretz, Foreign Affairs, Ynet News, The Forward Simon Hattenstone (born 29 December 1962 in Salford, England) journalist and writer; features writer and interviewer for The Guardian. He has also written or ghost-written a number of biographical books. Paula Heimann; (2 February 1899 – 22 October 1982), author, academic, psychiatrist and psychoanalyst who established phenomenon of countertransference as important tool of psychoanalytic treatment, publishing influential studies, texts, academic papers and monographs; member of British Psychoanalytical Society; author of monograph A contribution to the problem of sublimation and paper On counter-transference, presented at the Psychoanalytical Congress in 1949 in Zurich, led to rift with Kleinian group of analysts; later turned to the Independents group and was Margarete Mitscherlich's analyst; Alexander Mitscherlich also underwent training analysis with her. Margot Heinemann (18 November 1913 – 10 June 1992) was a British Marxist writer, drama scholar, and leading member of the Communist Party of Great Britain (CPGB).
2015: Edgar Savisaar, Estonian politician, had his right leg amputated. He got the disease during a trip to Thailand. 2018: Alex Smith, an American football quarterback for the Washington Football Team of the National Football League (NFL), contracted the disease after being injured during a game. He suffered an open compound fracture in his lower leg, which became infected. Smith narrowly avoided amputation and eventually returned to playing professional football in October 2020. Smith's injury and recovery is the subject of the ESPN documentary E60 Presents: Project 11. 2019: OG Maco contracted NF after an untreated rash. 2021: Irish actor Barry Keoghan revealed in 2024 that he contracted NF shortly before filming The Banshees of Inisherin and nearly had his arm amputated.
Sources: en.wikipedia.org
=== Cardiac muscle sarcomeric contractile function === PKCε translocates to cardiac muscle sarcomeres and modulates contractility of the myocardium. PKCε binds RACK2 at Z-lines with an EC50 of 86 nM; PKCε also binds at costameres to syndecan-4. PKCε has been shown to bind F-actin in neurons, which modulates synaptic function and differentiation; however it is unknown whether PKCε binds sarcomeric actin in muscle cells. Sarcomeric proteins have been identified in PKCε signaling complexes, including actin, cTnT, tropomyosin, desmin, and myosin light chain-2; in mice expressing a constitutively-active PKCε, all sarcomeric proteins showed greater association with PKCε, and the cTnT, tropomyosin, desmin and myosin light chain-2 exhibited changes in post-translational modifications. PKCε binds and phosphorylates cardiac troponin I (cTnI) and cardiac troponin T (cTnT) in complex with troponin C (cTnC); phosphorylation on cTnI at residues Serine-43, Serine-45, and Threonine-144 cause depression of actomyosin S1 MgATPase function. These studies were further supported by those performed in isolated, skinned cardiac muscle fibers, showing that in vitro phosphorylation of cTnI by PKCε or Serine-43/45 mutation to Glutamate to mimic phosphorylation desensitized myofilaments to calcium and decreased maximal tension and filament sliding speed. Phosphorylation on cTnI at Serine-5/6 also showed this depressive effect. Further support was gained from in vivo studies in which mice expressing a mutant cTnI (Serine43/45Alanine) exhibited enhanced cardiac contractility.
transcriptomics The study of the transcriptome of a particular genome, cell, or organism, i.e. the sum total of all of the RNA transcripts produced from it by transcription. Transcriptomics technologies allow scientists to isolate and sequence transcriptomes, which can then be mapped to the genome to determine which genes are being expressed or which cellular processes are active and which are dormant at a given time.
=== Zinc selenide white LEDs === Experimental white LEDs have been developed using homoepitaxially grown zinc selenide (ZnSe) on ZnSe substrates. These LEDs lack the yellow phosphors found in conventional white LEDs. In ZnSe LEDs, the active region emits blue light, while the conductive ZnSe substrate emits yellow light, resulting in white light output. Researchers suggest these LEDs offer lower operating voltages and a wider range of color temperatures than conventional white LEDs.
Fbw7 is known to be a haplo-insufficient tumor suppressor gene implicated in several sporadic carcinomas, for which one mutant allele is enough to disturb the wild type phenotype. Fbxo4 is another tumor suppressor FBP that has been implicated in human carcinomas. SCF-fbxo4 plays a role in cell cycle control by targeting cyclin D1 for degradation. Cyclin F is an FBP that is associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Mutations that prevent phosphorylation of Cyclin F alter the activity of SCF-Cyclin F, which likely affects downstream processes pertinent to neuron degeneration in ALS and FTD. Normally, Cyclin F targets E2f1 for degradation.
Sources: en.wikipedia.org
不是。Semax 是完全人工合成的七肽，自然界中没有对应的已知肽段。它的设计灵感来自促肾上腺皮质激素片段 ACTH(4-10)，但序列经过了替换和延长。
Semax 被描述为 ACTH(4-10) 的结构类似物，两者共享部分序列特征。它保留了该片段的部分神经相关活性方向，但去除了完整片段带来的激素释放效应。二者并非同一物质，也不能互相替代。
加入的 Pro-Gly-Pro 三肽被普遍认为能提升分子对蛋白水解酶的稳定性。这种设计让短肽在体内维持时间更长。具体延长的程度以及不同组织中是否一致，文献中仍存在不同报告。
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.