ACTH(4–10) 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.
Last reviewed on 2025-10-19. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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 |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
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。
=== Mindfulness === Langer is known for her contributions to the study of mindfulness and of mindless behaviour, which provided the basis for many studies focused on individual differences in unconscious behavior and decision-making processes in humans. Although she initially studied meditation as well, she grew to focus more on the study of mindfulness without meditation. In 1989, she published Mindfulness, arguing for the widespread influence and application of mindfulness to business, education, science, art, and interpersonal relationships, and she became known as the "mother of mindfulness". Langer defines mindfulness as "the simple act of noticing new things." The Langer Mindfulness Scale aims to proxy for measures of this form of mindfulness. Langer says that mindfulness can help teach that "uncertainty is the rule rather than the exception."
=== Láadan === Láadan is not agglutinating as there is no mechanism to combine arbitrary words into one without intermediating grammatical mechanisms (such as the relativizer § In other languages); however, there are a number of affixes that further elucidate the contextual meaning of a word. These are ignored when determining the longest words in the language. The primary reference for vocabulary is the 3rd edition of the official dictionary and grammar.
== Sources == Rupert, James (14 January 1992). "Christian Knights Claim Key Role in Georgia". The Washington Post. Bonner, Raymond (16 November 1993). "Georgian Fighter Wields Guns, Money and Charm". The New York Times. "Dzhaba Ioseliani, 76; Oft-Imprisoned Leader of Georgian Paramilitary Force". Associated Press. 5 March 2003 – via Los Angeles Times. Corley, Felix (25 March 2003). "Jaba Ioseliani: Violent warlord in post-Communist Georgia". The Independent. "Shevardnadze Is Wounded By Car Bomb In Georgia (Published 1995)". 1995-08-30. Archived from the original on 2024-04-23. Retrieved 2026-01-18. "Georgians Held in Failed Assassination of Shevardnadze". Los Angeles Times. 1995-09-19. Retrieved 2026-01-18. "IOSELIANI AND ACCOMPLICES SENTENCED. - Jamestown". jamestown.org. Retrieved 2026-01-18. "1997 Human Rights Report: Georgia". 1997-2001.state.gov. Retrieved 2026-01-18.
Sources: en.wikipedia.org
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In 2016, Beginning Investing defined US mega-caps as having market caps over $100 billion (equivalent to $128 billion in 2024 using GDP deflator adjustment). The Principal US Mega-Cap ETF's inception was on October 11, 2017; however, until June 10, 2022, it used a different investment strategy. The S&P 500 Top 10 Index was launched on July 14, 2023. The MSCI USA Mega Cap Select Index was created circa February 2024. The S&P 500 Top 20 Index was launched on August 1, 2024. In the same year, the seventh edition of Stock Investing For Dummies was published; it continued to use $200 billion as the minimum market cap cutoff for megacaps, unchanged from the sixth edition.
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Sources: en.wikipedia.org
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
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.