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 2026-05-06. 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。
| 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 developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
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.
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.
24 May – Researchers from the Chinese Academy of Sciences report tuning of the Casimir effect using magnetic fields. 30 May – NASA reports that the James Webb Space Telescope has discovered JADES-GS-z14-0, the most distant known galaxy, which existed only 290 million years after the Big Bang. Its redshift of 14.32 exceeds the previous record of 13.2, set by JADES-GS-z13-0. 31 May – Biologists report that Tmesipteris oblanceolata, a fern ally plant, was found to contain the largest known genome. Promising results of health and medical research are reported: a mRNA vaccine-like immunotherapy against brain cancer tested in a preliminary small trial (1 May), ferrets-tested mRNA vaccine against the clade 2.3.4.4b H5 bird flu amid concerning developments of the 2020–2025 H5N1 outbreak (23 May), mice-tested antibiotic lolamicin specific to Gram-negative bacteria that spares the gut microbiome (29 May).
== External links == Ernest Beutler (1928–2008) – Profile, including an oral history, from The American Society of Hematology. Scientific Publications – All publications of articles by Ernest Beutler listed in PubMed. Marshall A. Lichtman, "Ernest Beutler", Biographical Memoirs of the National Academy of Sciences (2012)
Following the first September airstrike, Maduro said that the US was "coming for Venezuela's riches". Maduro stated that "Venezuela is confronting the biggest threat that has been seen on our continent in the last 100 years." In a display of its military strength, Venezuela initiated large-scale military exercises in the Caribbean on 17 September. The maneuvers, involving naval and air forces, were intended to bolster the nation's defense capabilities and demonstrate its readiness to protect its sovereign waters. Padrino López announced Operation Sovereign Caribbean 200 (Caribe Soberano 200) would take place on La Orchila Island aiming "to strengthen defensive capabilities and protect national sovereignty" in direct response to "the threatening and vulgar deployment of U.S. ships in the Caribbean". Following another airstrike, on 15 October 2025, Maduro declared new military exercises in Caracas shantytowns and nearby states. On 22 October, Maduro warned the US that the National Bolivarian Armed Forces had more than 5,000 Russian-made Igla-S man-portable surface-to-air-missile systems in "... key anti-aircraft defense positions to guarantee peace, stability, and tranquility". Padrino Lopez responded to the expansion after the seizure of Skipper, saying on 12 December: "We've been watching ... don't be mistaken. We're ready to defend this country. You're not going to intimidate us." According to Reuters, the Venezuelan military is considering two strategies in preparation for a US attack.
Sources: en.wikipedia.org
== Mechanism of action == Like all opioid drugs, ADL-5859 activates opioid receptors, but where as traditional opioids (such as oxycodone) activate the three main receptors (mu, delta, and kappa), ADL-5859 appears to be selective and only activates the delta receptor. with a Ki of 20 nM
A liver biopsy (tissue examination) is the only test widely accepted (gold standard) as definitively diagnosing and distinguishing MASLD and MASH from other forms of liver disease. It can be used to assess the severity of inflammation and resultant fibrosis. However, since most people affected by MASLD are likely to be asymptomatic, liver biopsy presents too high a risk for routine diagnosis, so other methods are preferred, such as liver ultrasonography or liver MRI. For young people, guidelines recommend liver ultrasonography, but biopsy remains the best evidence. Liver biopsy is also the gold standard to detect hepatic fibrosis and assess its progression. Routine liver function blood tests are not sensitive enough to detect MASLD, and biopsy is the only procedure that can reliably differentiate MASLD from MASH. There are several liver biopsy techniques available to obtain liver tissue. Percutaneous liver biopsy remains the most common practice. Biopsies can also be performed via the transvenous route, either during surgery or by laparoscopy, especially for people with contraindications to a percutaneous approach. The liver biopsy can also be image-guided, in real-time or not, which is recommended for some clinical situations, such as people with known liver lesions, previous intra-abdominal surgery who may have adhesions, a small liver that is difficult to percuss, people with obesity, and people with evident ascites.
=== Definition === The EU defines biopesticides as "a form of pesticide based on micro-organisms or natural products". The US EPA defines biopesticides as “certain types of pesticides derived from such natural materials as animals, plants, bacteria, and certain minerals”. Microorganisms that control pests may also be categorised as biological pest control agents together with larger organisms such as parasitic insects, entomopathic nematodes etc. Natural products may also be categorised as chemical insecticides. The US EPA describes three types of biopesticide. Biochemical pesticides (meaning bio-derived chemicals), which are naturally occurring substances that control pests by non-toxic mechanisms. Microbial pesticides consisting of a microorganism (e.g., a bacterium, fungus, virus or protozoan) as the active ingredient. Plant-Incorporated-Protectants (PIPs) are pesticidal substances that plants produce from genetic material that has been added to the plant (thus producing transgenic crops).
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。
不存在。它是依据 ACTH 的一段序列人工设计的分子，天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号，而非天然物质名。