A practical reference on heptapeptide: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-13. Anything still debated is marked as such rather than presented as settled.
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。
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.
=== Continuous stirred-tank reactor === In an ideal continuous stirred-tank reactor (CSTR), the flow at the inlet is completely and instantly mixed into the bulk of the reactor. The reactor and the outlet fluid have identical, homogeneous compositions at all times. The residence time distribution is exponential:
=== Acquisition of ZLB Bioplasma AG and Aventis Behring === In 2000, CSL doubled its size through the purchase of a Swiss plasma company, the Bern-based ZLB Bioplasma AG. In 2004, during a period of plasma oversupply, the company expanded again with the purchase of the German medical company Aventis Behring. The company was the second Australian public company to have reached a share price of over $100 per share.
==== Dimethyltryptamine ==== Dimethyltryptamine (DMT) is a naturally occurring, serotonergic hallucinogen found in plants and mammals, classified as a DEA Schedule I substance with no accepted medical use, and under investigation for clinical applications. Ayahuasca's psychoactive effects stem mainly from DMT, made orally active by MAOIs in the B. caapi vine, and its activation of serotonin receptors, particularly 5-HT2A, with additional contributions from harmine and harmaline.
Sources: en.wikipedia.org
== Discovery == Humanin was the first mitochondria-derived peptide to be discovered. Humanin was independently found by three different labs looking at different parameters. The first to publish, in 2001, was the Nishimoto lab, which found humanin while looking for possible proteins that could protect cells from amyloid beta, a major component of Alzheimer's disease. The Reed lab found humanin when screening for proteins that could interact with Bcl-2-associated X protein (Bax), a major protein involved in apoptosis. The Pinchas Cohen lab independently discovered humanin when screening for proteins that interact with IGFBP3.
high affinity towards the target (less than 1 μM) selectivity versus other targets significant efficacy in a cellular assay druglikeness (moderate molecular weight and lipophilicity usually estimated as ClogP). Affinity, molecular weight and lipophilicity can be linked in single parameter such as ligand efficiency and lipophilic efficiency. low to moderate binding to human serum albumin low interference with P450 enzymes and P-glycoproteins low cytotoxicity metabolic stability high cell membrane permeability sufficient water solubility (above 10 μM) chemical stability synthetic tractability patentability The project team will usually select between three and six compound series to be further explored. The next step will allow the testing of analogous compounds to determine a quantitative structure-activity relationship (QSAR). Analogs can be quickly selected from an internal library or purchased from commercially available sources ("SAR by catalog" or "SAR by purchase"). Medicinal chemists will also start synthesizing related compounds using different methods such as combinatorial chemistry, high-throughput chemistry, or more classical organic chemistry synthesis.
== Effectiveness == Negative pressure wound therapy is usually used with chronic wounds or wounds that are expected to present difficulties while healing (such as those associated with diabetes). Negative pressure wound therapy is approved by the FDA and numerous randomized controlled trials have been conducted on this technique, however, the evidence supporting how effective NPWT is compared to standard wound care dressings is not clear. Low-level evidence indicates that there may be a lower risk of death and less surgical site infections associated with NPWT compared to standard dressing care, however there may not be a difference in the risk of wound reopening when comparing the two approaches. NPWT may increase the risk of skin blistering compared to standard wound care. NPWT may be a more cost effective approach for closing wounds following a caesarean section in women who are obese, however, NPWT is not likely as cost effective for closing wounds associated with fracture surgeries. It is not clear if NPWT is cost effective for closing wounds associated with other types of surgery. NPWT has been used to treat non-trauma patients after abdominal surgery. Non-trauma patients are people who might need surgery for conditions such as abdominal infections or cancer. However, it is still not clear how safe and effective NPWT is for treating non-trauma patients with open abdomens. For treating diabetic ulcers of the feet, "consistent evidence of the benefit of NPWT" in the treatment of diabetic ulcers of the feet has been reported.
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.