A practical reference on ACTH(4-10): what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-03-06 and is reviewed periodically as new material appears.
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 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.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
| 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 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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
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.
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.
== See also == Control of water pollution – Contamination of water bodies Clean Water Act – 1972 U.S. federal law regulating water pollution Peak water – Concept on the quality and availability of freshwater resources Pulsed-power water treatment – Using electro-magnetic fields on cooling water Solar water disinfection – Portable water purification powered by sunlight Raw water#Treatment – Untreated water found in a natural environment Water purification – Process of removing impurities from water Water quality – Assessment against standards for use Water softening – Removing positive ions from hard water Water supply – Provision of water by public utilities, commercial organisations or others
=== Academics and Islamic scholars === Muhammad Ibn Muhammad Al-Fulani Al-Kishwani – prominent mathematician in the early 1700s from Katsina Usman dan Fodio (1754–1817) – Islamic scholar, revolutionary from Sokoto, founder and spiritual leader of the Sokoto Caliphate. Abdullahi dan Fodio (1766–1829) – scholar, jurist, pioneer, Grand Vizier of Sokoto and first Emir of Gwandu (r. 1812–1828). Nana Asma'u – princess, poet, Islamic scholar and daughter of Usman dan Fodio. Muhammed Bello (1781–1837) – the first sultan of Sokoto. Abd al-Qadir dan Tafa (1804–1864) – described as the "most learned scholar of his time" in the Sokoto Caliphate who specialized in philosophy (Falsafa) Abu Bakr Atiku (1782–1842) – second sultan of the Sokoto Caliphate, reigning from October 1837 until November 1842. Muhammadu Junaidu – former grand vizier of Sokoto, historian, writer Hayatu ibn Sa'id - great-grandson of Usman dan Fodio, Mahdist leader who attempted to conquer Bornu and The Sokoto Caliphate. Muhammad Bukhari bin Uthman - military commander, scholar and poet. Son Of Usman dan Fodio. Modibbo Adama (1786–1847) – first Laamiɗo and founder of Fombina (Adamawa emirate) which covered parts of Nigeria, Cameroon and Chad. Modibbo Raji – influential 19th century Islamic scholar who is generally regarded as the founder of the Islamic scholarly tradition in Adamawa;Wazir(vizier) in the Gwandu Emirate of the Sokoto Caliphate Muhammad Auwal Albani Zaria - prominent Islamic scholar and reformer. Isa Ali Pantami - Islamic scholar, former Minister of Communications and Digital economy.
The Annals of Clinical & Laboratory Science is a quarterly academic journal. It is the official journal of, and is published by, the Association of Clinical Scientists. It was established in 1971 as Annals of Clinical Laboratory Science by F. William Sunderman and obtained its current title in 1973. As of 2022, the editor-in-chief is Nina Tatevian.
Sources: en.wikipedia.org
The hydrophobic effect is the observed tendency of nonpolar substances to aggregate in an aqueous solution and to be excluded by water. The word hydrophobic literally means "water-fearing", and it describes the segregation of water and nonpolar substances, which maximizes the entropy of water and minimizes the area of contact between water and nonpolar molecules. In terms of thermodynamics, the hydrophobic effect is the free energy change of water surrounding a solute. A positive free energy change of the surrounding solvent indicates hydrophobicity, whereas a negative free energy change implies hydrophilicity. The hydrophobic effect is responsible for the separation of a mixture of oil and water into its two components. It is also responsible for effects related to biology, including: cell membrane and vesicle formation, protein folding, insertion of membrane proteins into the nonpolar lipid environment and protein-small molecule associations. Hence the hydrophobic effect is essential to life. Substances for which this effect is observed are known as hydrophobes.
24998Cf + 157N → 260105 + 4 n These results did not confirm the JINR findings regarding the 9.4 MeV or 9.7 MeV alpha decay of 260105, leaving only 261105 as a possibly produced isotope. JINR then attempted another experiment to create element 105, published in a report in May 1970. They claimed that they had synthesized more nuclei of element 105 and that the experiment confirmed their previous work. According to the paper, the isotope produced by JINR was probably 261105, or possibly 260105. This report included an initial chemical examination: the thermal gradient version of the gas-chromatography method was applied to demonstrate that the chloride of what had formed from the SF activity nearly matched that of niobium pentachloride, rather than hafnium tetrachloride. The team identified a 2.2-second SF activity in a volatile chloride portraying eka-tantalum properties, and inferred that the source of the SF activity must have been element 105. In June 1970, JINR made improvements on their first experiment, using a purer target and reducing the intensity of transfer reactions by installing a collimator before the catcher. This time, they were able to find 9.1 MeV alpha activities with daughter isotopes identifiable as either 256103 or 257103, implying that the original isotope was either 260105 or 261105.
== Mechanism == Aspartate transaminase, as with all transaminases, operates via dual substrate recognition; that is, it is able to recognize and selectively bind two amino acids (Asp and Glu) with different side-chains. In either case, the transaminase reaction consists of two similar half-reactions that constitute what is referred to as a ping-pong mechanism. In the first half-reaction, amino acid 1 (e.g., L-Asp) reacts with the enzyme-PLP complex to generate ketoacid 1 (oxaloacetate) and the modified enzyme-PMP. In the second half-reaction, ketoacid 2 (α-ketoglutarate) reacts with enzyme-PMP to produce amino acid 2 (L-Glu), regenerating the original enzyme-PLP in the process. Formation of a racemic product (D-Glu) is very rare. The specific steps for the half-reaction of enzyme-PLP + aspartate
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。
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.