This is a working overview of ACTH(4-10), written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-06-07 and is reviewed periodically as new material appears.
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
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.
| Property | Value | Notes |
|---|---|---|
| 分子式 | C37H51N9O10S | 游离碱形式 |
| 等电点 | 约 6.5 | 估算值，随缓冲体系变化 |
| 主要降解途径 | 水解与氧化 | 侧链氧化最为常见 |
| 溶液储存 | 2 至 8 摄氏度避光 | 避免反复冻融 |
| 常规分析手段 | 反相色谱与质谱联用 | 氨基酸分析辅助核对 |
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
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.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
One interpretation of the data is that polypeptide monomers are often aligned in the multimer in such a way that mutant polypeptides defective at nearby sites in the genetic map tend to form a mixed multimer that functions poorly, whereas mutant polypeptides defective at distant sites tend to form a mixed multimer that functions more effectively. Direct interaction of two nascent proteins emerging from nearby ribosomes appears to be a general mechanism for homo-oligomer (multimer) formation. Hundreds of protein oligomers were identified that assemble in human cells by such an interaction. The most prevalent form of interaction is between the N-terminal regions of the interacting proteins. Dimer formation appears to be able to occur independently of dedicated assembly machines. The intermolecular forces likely responsible for self-recognition and multimer formation were discussed by Jehle.
Investigating the use of standardized HPLC methods, Valko's 2016 research suggested that Chromatographic properties measured at early stages of the drug discovery process can assess lipophilicity, oral absorption, volume of distribution, drug efficiency, and even early dose estimation. In related research, she introduced standardized procedures for accelerating drug discovery by evaluating in vivo distribution and non-specific binding through chromatographic profiling of analogs, highlighting the advantages over traditional metrics such as Ligand Lipophilicity Efficiency (LLE). Later, her 2018 work tackled peptide therapeutic challenges by assessing biomimetic properties like lipophilicity and membrane affinity via High-Performance Liquid Chromatography, using chemically bonded protein and immobilized artificial membrane stationary phases. Her 2021 suggested that membrane and alpha-1-acid glycoprotein retention can be considered as promising indices for assessing the ecotoxicological risk of drugs, with membrane models showing superior performance compared to those derived from the traditional octanol-water system. In addition, she also proposed a model using biomimetic HPLC methods and measured binding properties to predict hERG inhibition, addressing early screening for potential cardiotoxicity and reducing late-stage failures in drug discovery.
He said the deal had been brokered through a partnership with private business and mediated by Secretary of State Marco Rubio and Secretary of Defense Pete Hegseth. Trump claimed that the agreement came "at no cost to the American taxpayer" and would more than double U.S. oil reserves. Few details were disclosed regarding the legal and financial structure of the agreement, including which fields or companies were involved, or how the United States would exercise majority control over the reserves. The Washington Post reported that under the arrangement the United States had gained a controlling stake in nearly a quarter of Venezuela's untapped oil reserves, becoming the majority owner of a newly formed joint venture holding 100-year contracts at the fields, and that a list of 17 oil fields in which the United States would take a stake had circulated before the announcement. According to deal points reviewed by the newspaper, the United States government's stake would be split between equity ownership and guarantees that it would purchase oil produced by the venture at cost to refill the Strategic Petroleum Reserve. Several of the fields lacked infrastructure or access to transport hubs, and those where such infrastructure existed had suffered years of neglect and theft of machinery; the newspaper reported that it was unclear who would make the tens of billions of dollars of investment needed before oil could be pumped, major oil companies having largely regarded such spending as too risky.
Nanochemistry is an emerging sub-discipline of the chemical and material sciences that deals with the development of new methods for creating nanoscale materials. The term "nanochemistry" was first used by Ozin in 1992 as 'the uses of chemical synthesis to reproducibly afford nanomaterials from the atom "up", contrary to the nanoengineering and nanophysics approach that operates from the bulk "down"'. Nanochemistry focuses on solid-state chemistry that emphasizes synthesis of building blocks that are dependent on size, surface, shape, and defect properties, rather than the actual production of matter. Atomic and molecular properties mainly deal with the degrees of freedom of atoms in the periodic table. However, nanochemistry introduced other degrees of freedom that controls material's behaviors by transformation into solutions. Nanoscale objects exhibit novel material properties, largely as a consequence of their finite small size. Several chemical modifications on nanometer-scaled structures approve size dependent effects. Three specializations of nanochemistry are molecular nanotopology, nanointerface chemistry and nanoelectrochemistry. Nanochemistry is used in chemical, materials and physical science as well as engineering, biological, and medical applications. Silica, gold, polydimethylsiloxane, cadmium selenide, iron oxide, and carbon are materials that show its transformative power. Nanochemistry can make the most effective contrast agent of MRI out of iron oxide (rust) which can detect cancers and kill them at their initial stages.
Sources: en.wikipedia.org
Benzodiazepines are usually administered orally; however, very occasionally lorazepam or diazepam may be given intravenously for the treatment of panic attacks. Because of their effectiveness, tolerability, and rapid onset of anxiolytic action, benzodiazepines are frequently used for the treatment of anxiety associated with panic disorder. However, there is disagreement among expert bodies regarding the long-term use of benzodiazepines for panic disorder. The views range from those holding benzodiazepines are not effective long-term and should be reserved for treatment-resistant cases to those holding they are as effective in the long term as selective serotonin reuptake inhibitors (SSRIs). American Psychiatric Association (APA) guidelines, published in January 2009, note that, in general, benzodiazepines are well tolerated, and their use for the initial treatment for panic disorder is strongly supported by numerous controlled trials. APA states that there is insufficient evidence to recommend any of the established panic disorder treatments over another. The choice of treatment between benzodiazepines, SSRIs, serotonin–norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, and psychotherapy should be based on the patient's history, preference, and other individual characteristics. Selective serotonin reuptake inhibitors are likely to be the best choice of pharmacotherapy for many patients with panic disorder, but benzodiazepines are also often used, and some studies suggest that these medications are still used with greater frequency than the SSRIs.
== Clinical trials == Tedizolid proved its noninferiority to linezolid in two phase-III trials, known as the ESTABLISH trials. Tedizolid is the second treatment approved by the US Food and Drug Administration (FDA) under the Generating Antibiotic Incentives Now (known as the GAIN Act) federal law. New antibiotics manufactured under the act will be designated as a Qualified Infectious Disease Product (QIDP), allowing an expedited review by the FDA and an additional five years of market exclusivity.
Catabolism of catecholamines is mediated by two main enzymes: catechol-O-methyltransferase (COMT) which is present in the synaptic cleft and cytosol of the cell and monoamine oxidase (MAO) which is located in the mitochondrial membrane. Both enzymes require cofactors: COMT uses Mg2+ as a cofactor while MAO uses FAD. The first step of the catabolic process is mediated by either MAO or COMT which depends on the tissue and location of catecholamines (for example degradation of catecholamines in the synaptic cleft is mediated by COMT because MAO is a mitochondrial enzyme). The next catabolic steps in the pathway involve alcohol dehydrogenase, aldehyde dehydrogenase and aldehyde reductase. The end product of epinephrine and norepinephrine is vanillylmandelic acid (VMA) which is excreted in the urine. Dopamine catabolism leads to the production of homovanillic acid (HVA).
Sources: en.wikipedia.org
It is a key feature of NMR that the resonance frequency of nuclei in a particular sample substance is usually directly proportional to the strength of the applied magnetic field. It is this feature that is exploited in imaging techniques; if a sample is placed in a non-uniform magnetic field then the resonance frequencies of the sample's nuclei depend on where in the field they are located. This effect serves as the basis of magnetic resonance imaging. The principle of NMR usually involves three sequential steps:
=== Excretion === The elimination of 2,6-DCBQ and its derivatives occurs predominantly through the renal system. Due to its high reactivity, levels of the unchanged parent compound are negligible. Instead, the compound is excreted in the form of water-soluble metabolites, specifically mercapturic acid derivatives. Biliary excretion is a secondary possibility, but urinary elimination remains the dominant pathway for the clearance of 2,6-DCBQ metabolites from the body.
Soon after Neo leaves, dozens of Smiths come and assimilate Seraph, Sati and the Oracle. Neo and Trinity are given the Logos, a hovercraft commanded by Morpheus's former lover, Niobe, in what seems to others as a suicidal journey to the Machine City. Meanwhile, Captain Roland and the Nebuchadnezzar's surviving crew of Link and Morpheus in the hovercraft Hammer/Mjolnir return to Zion, which is now besieged and losing to the Machines. Neo and Trinity are ambushed by the stowaway Bane/Smith, who blinds Neo with an electric cable, but is killed when Neo discovers an ability to "see" programs and machines independently without his eyesight. Neo, with Trinity as pilot, guides the Logos past the Machine City's defenses, but in the effort the Logos crash-lands, and Trinity sustains fatal injuries and dies. Neo encounters the Deus Ex Machina, a giant machine construct and the leader of the machines. He offers Smith's defeat and destruction to the Deus in exchange for a truce. The offer is accepted; Neo enters the Matrix to find that Smith has copied himself throughout the simulated world, now truly threatening the safety and stability of the Matrix. One of the copies of Smith, having assimilated the Oracle and obtained as much freedom and control over the virtual world as Neo, faces Neo alone. For a while, the two fight evenly with no real advantage, but ultimately, the tireless Smith begins to wear out Neo and takes control of the fight.
Sources: en.wikipedia.org
电喷雾或基质辅助激光解吸电离质谱是常用手段，测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内，才支持结构一致的判断。
甲硫氨酸侧链含硫醚，在氧气、光照或金属离子存在时容易被氧化。氧化产物极性略增，常在色谱图上表现为主峰之前的肩峰或前伸峰。
通常建议冷藏避光，并在较短时间内使用。不存在适用于所有配方的统一期限，具体取决于浓度、缓冲体系与容器材质。
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.