heptapeptide 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 2026-06-08. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
| 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 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.
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 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.
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.
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.
=== 1989 === January 4: Gulf of Sidra incident between America and Libya, similar to the 1981 Gulf of Sidra incident. January 7: Emperor Hirohito dies, marking the end of the Showa era in Japan. January 11: Communist Hungary introduces political reforms. January 19: The trade union Solidarity is legalized by the Polish government. January 20: George H. W. Bush is inaugurated as 41st President of the United States. February 2: Soviet troops withdraw from Afghanistan. February 3: Alfredo Stroessner was deposed in a coup led by Andrés Rodríguez. February 14: The Contra war effectively ends with the Tesoro Beach Accords happening in El Salvador with Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua participating. An agreement is made that all contra forces are to disband in return for a free election to be held in February 1990. Although a few groups initially reject the agreement they eventually decide to participate. February 15: The Afghan Civil War begins after Soviet troops withdrawing from Afghanistan. February 19–21: Jakarta Informal Meeting II was held in Jakarta. This meeting succeeded in finding two important issues, namely the withdrawal of Vietnamese troops from Cambodia and the prevention of the return of the Pol Pot regime in Cambodia. Later, efforts to resolve the conflict will continue in International Conference in Paris on July 30–31, 1989. March 26: The Soviet Union holds the first round of legislative elections to the Congress of People's Deputies. June 3: Ayatollah Khomeini dies.
=== Formulated intermediate moisture foods === Many types of food are specially formulated to achieve water activity in the IMF range. Food ingredients are mixed with salt and/or sugar, and additives (such as propylene glycol and potassium sorbate) and then subjected to processing methods such as cooking, extrusion or dehydration to result in an intermediate moisture final product. Examples of formulated IMF are confectioneries and pet food.
=== Experimental techniques === Many researchers around the world are investigating the pathogenesis of diabetes and beta-cell failure. Tools used to study beta-cell function are expanding rapidly with technology. For instance, transcriptomics have allowed researchers to comprehensively analyze gene transcription in beta-cells to look for genes linked to diabetes. Another technique to measure cellular function is cell imaging, notably with confocal or TIRF microscopy. Beta-cells can be modified to express a fluorophore that specifically labels insulin granules, which allows granule tracking and exocytosis measurement. Concerning calcium imaging, fluorescent dyes bind to calcium and allow in vitro imaging of calcium activity which correlates directly with insulin release. A final tool used in beta-cell research are in vivo experiments. Diabetes mellitus can be experimentally induced in vivo for research purposes by streptozotocin or alloxan, which are specifically toxic to beta cells. Mouse and rat models of diabetes also exist including ob/ob and db/db mice which are a type 2 diabetes model, and non-obese diabetic mice (NOD) which are a model for type 1 diabetes.
Sources: en.wikipedia.org
== Use and effects == The 25-NB drugs are inactive orally and instead are typically used sublingually, buccally, by insufflation, or sometimes via inhalation. They are typically employed at doses in the range of 50 to 1,500 μg, variable depending on the specific drug, and have durations in the range of 3 to 12 hours. The table below provides an overview of the major 25-NB drugs and their properties. Conventionally, 25-NB have been known to be orally inactive due to extensive first-pass metabolism. However, an orally active N-benzylphenethylamine with an atypical chemical structure known as BMB-202 has since been identified and is under development for potential medical use. It is predicted to have a fast onset and a short duration of 1 to 2 hours in humans.
=== Short films === Phang directed, wrote and edited a short film entitled Advantageous (2012) - the basis of the 2015 feature film of the same name - which imagined various scenarios and stories that took place in the future. The film won a Best Science Fiction Film award at the Rhode Island International Horror Film Festival and also the Golden Reel Award for Best Short Film at the 2012 Los Angeles Film Festival. It was also nominated for "Best Short Film" at Fantastic Fest, the Cleveland International Film Festival, the Philadelphia Asian American Film Festival, the Philadelphia Film Festival, the Asian American International Film Festival, the San Diego Asian Film Festival, the San Diego Comic-Con Independent Film Festival, and the Urbanworld Film Festival. Other short films that Phang directed include Midnight Boycow (2007) starring Rex Lee and Love, Ltd. (2000), which Phang also co-wrote with Jeff Kirschenbaum.
Didanosine (ddI), sold under the brand name Videx among others, is a medication used to treat HIV/AIDS. It is used in combination with other medications as part of highly active antiretroviral therapy (HAART). It is of the reverse-transcriptase inhibitor class. Didanosine was first described in 1975 and approved for use in the United States in 1991.
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。
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.