Semax 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.
Updated 2026-07-25. Numbers and descriptions here follow the published literature rather than marketing material.
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。
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
| 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 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.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
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 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.
Gokhan Okan, Can Baykal, Rifkiye Sarica. "Childhood bullous pemphigoid developed after the first vaccination." Journal of Dermatological Treatment Gokhan Okan, Pervin Vural. "Worsening of the vitiligo following the second dose of the BNT162B2 mRNA COVID‐19 vaccine." Journal of Dermatological Treatment Gokhan Okan, Adile Merve Baki, Eda Yorulmaz, Semra Doğru‐Abbasoğlu, and Pervin Vural. "Serum Visfatin, Fetuin‐A, and Pentraxin 3 Levels in Patients with Psoriasis and Their Relation to Disease Severity". Journal of clinical laboratory analysis. Gokhan Okan, and Halil Ibrahim Canter. "Nicolau syndrome and perforator vessels: a new viewpoint for an old problem". Journal of Cutaneous and Ocular Toxicology. Gokhan Okan, and Can Baykal. "Nevoid hyperkeratosis of the nipple and areola: treatment with topical retinoic acid". Journal of the European Academy of Dermatology and Venereology. Gokhan Okan, Serpil Yaylaci, Onder Peker, Sabahattin Kaymakoglu, and Murat Saruc. "Vanishing bile duct and Stevens-Johnson syndrome associated with ciprofloxacin treated with tacrolimus". World Journal of gastroenterology. Can Baykal, Gökhan Okan, and Rifkiye Sarica. "Childhood bullous pemphigoid developed after the first vaccination". Journal of the American Academy of Dermatology. Gökhan Okan, "Atopik dermatitin baş boyun lokalizasyonlarında pityrosporum ovalenin rolü". ("The role of pityrosporum ovalen in head and neck localization of atopic dermatitis.") Gokhan Okan, Adile Merve Baki, Eda Yorulmaz, Semra Dogru-Abbasoglu, Pervin vural.
In organic chemistry, a carbodiimide (systematic IUPAC name: methanediimine) is a functional group with the formula RN=C=NR. On Earth they are exclusively synthetic, but in interstellar space the parent compound HN=C=NH has been detected by its maser emissions. A well known carbodiimide is dicyclohexylcarbodiimide, which is used in peptide synthesis. Dialkylcarbodiimides are stable. Some diaryl derivatives tend to convert to dimers and polymers upon standing at room temperature, though this mostly occurs with low melting point carbodiimides that are liquids at room temperature. Solid diaryl carbodiimides are more stable, but can slowly undergo hydrolysis in the presence of water over time.
=== Cartilage transplants === In 2021, researchers from Swansea University partnered with the Scar Free Foundation to bioprint 3D transplantable cartilage made of human stem cells and plant-based materials to give a 10-year-old girl an ear transplant. This method eliminated the need to retrieve cartilage from elsewhere on the patient's body.
Sources: en.wikipedia.org
==== US Federal Trade Commission ==== On 27 February 2019, the United States Federal Trade Commission (FTC) reached a consent decree with ByteDance, fining it US$5.7 million for collecting information from minors under the age of 13 in violation of the Children's Online Privacy Protection Act (COPPA). ByteDance responded by adding a kids-only mode to TikTok which blocks the upload of videos, the building of user profiles, direct messaging, and commenting on others' videos, while still allowing the viewing and recording of content. In May 2020, an advocacy group filed a complaint with the FTC saying that TikTok had violated the terms of the February 2019 consent decree with the FTC, which sparked subsequent congressional calls for a renewed FTC investigation. In March 2022, following a class action lawsuit for violations of COPPA, TikTok settled for US$1.1 million. In March 2024, it was reported that the FTC continues to investigate TikTok. In August 2024, the FTC and US Department of Justice filed a joint lawsuit alleging violations of the 2019 consent decree. In August 2026, TikTok and ByteDance agreed to pay $400 million to settle the lawsuit.
==== Sucrase ==== Function: Sucrase is a stomachs related protein that mobilizes hydrolysis to convert sucrose into glucose and fructose. Clinical Significance: Low amounts of Sucrose also known as Sucrose intolerance happens when sucrose isn't being discharged in the small digestive tract. A result of this is extra gas.
== Medical use == Polymyxin antibiotics are relatively neurotoxic and nephrotoxic, so are usually used only as a last resort if modern antibiotics are ineffective or are contraindicated. Typical uses are for infections caused by strains of multiple drug-resistant Pseudomonas aeruginosa or carbapenemase-producing Enterobacteriaceae. Polymyxins have less effect on Gram-positive organisms, and are sometimes combined with other agents (as with trimethoprim/polymyxin) to broaden the effective spectrum. Polymyxins B are not absorbed from the gastrointestinal tract, so they are only administered orally if the goal is to disinfect the GI tract. Another route of administration is chosen for systemic treatment, e.g., parenteral (often intravenously) or by inhalation. They are also used externally as a cream or drops to treat otitis externa (swimmers ear), and as a component of triple antibiotic ointment to treat and prevent skin infections.
Sources: en.wikipedia.org
== Pathology == Abnormally elevated levels of glucagon may be caused by pancreatic tumors, such as glucagonoma, symptoms of which include necrolytic migratory erythema, reduced amino acids, and hyperglycemia. It may occur alone or in the context of multiple endocrine neoplasia type 1. Elevated glucagon is the main contributor to hyperglycemic ketoacidosis in undiagnosed or poorly treated type 1 diabetes. As the beta cells cease to function, insulin and pancreatic GABA are no longer present to suppress the freerunning output of glucagon. As a result, glucagon is released from the alpha cells at a maximum, causing a rapid breakdown of glycogen to glucose and fast ketogenesis. It was found that a subset of adults with type 1 diabetes took 8 hours longer on average (18 hours vs 10 hours) to approach ketoacidosis when given somatostatin (inhibits glucagon production) with no insulin. Inhibiting glucagon has been a popular idea of diabetes treatment, however, some have warned that doing so will give rise to brittle diabetes in patients with adequately stable blood glucose. The absence of alpha cells (and hence glucagon) is thought to be one of the main influences in the extreme volatility of blood glucose in the setting of a total pancreatectomy.
==== Grafting onto ==== Grafting to involves the strong adsorption or chemical bonding of a polymer molecule to a surface from solution. This process is typically achieved through a coupling agent that links a handle on the surface to a reactive group on either of the chain termini. Although simple, this approach suffers from the disadvantage of a relatively low grafting density due to steric hindrance from the already-attached polymer coils. After coupling, as in all cases, polymers attempt to maximize their entropy typically by assuming a brush or mushroom conformation. Thus, potential binding sites become inaccessible beneath this "mushroom domain".
=== Two-step mechanism – autocatalysis model === In 1997, Finke and Watzky proposed a new kinetic model for the nucleation and growth of nanoparticles. This 2-step model suggested that constant slow nucleation (occurring far from supersaturation) is followed by autocatalytic growth where dispersity of nanoparticles is largely determined. This F-W (Finke-Watzky) 2-step model provides a firmer mechanistic basis for the design of nanoparticles with a focus on size, shape, and dispersity control. The model was later expanded to a 3-step and two 4-step models between 2004 and 2008. Here, an additional step was included to account for small particle aggregation, where two smaller particles could aggregate to form a larger particle. Next, a fourth step (another autocatalytic step) was added to account for a small particle agglomerating with a larger particle. Finally in 2014, an alternative fourth step was considered that accounted for a atomistic surface growth on a large particle.
== De facto ruler of Panama == Noriega preferred to remain behind the scenes, rather than become president, and to avoid the public scrutiny that came with the post. He did not have a particular social or economic ideology, and used military nationalism to unify his supporters. The Partido Revolucionario Democrático (Democratic Revolutionary Party, PRD), which had been established by Torrijos and had strong support among military families, was used by Noriega as a political front for the PDF. This party drew considerable support from low-income employees brought into the government bureaucracy by its expansion under Torrijos and Noriega. Noriega compelled the Panamanian National Assembly to pass Law 20 of 1983, which was supposedly aimed at protecting the Panama Canal from communists, and allowed a huge influx of U.S. weapons to the Panamanian military. The law also tripled the size of the military forces. Noriega's period in power saw significant capital flight from Panama; according to Kempe, this was at least in part because wealthy individuals worried that their wealth would be seized by Noriega's administration. The military government of Torrijos had maintained its power in large part by extracting resources from Panama's expanding service sector, particularly its illicit portions. According to political scientist Steve Ropp, Torrijos was a "gifted politician with a genuine concern for improving the economic lot of the average Panamanian", but his individual talent had a relatively small role to play in preserving his government.
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 main proposal is modulation of neurotrophic factors such as brain-derived neurotrophic factor, supported largely by animal experiments. Receptor-level targets have not been firmly established. Most reviews describe the mechanism as only partially characterized.