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 2026-03-10 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。
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.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
| 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 |
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.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
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.
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.
4-Fluoro-7-nitrobenzofurazan (NBD-F) is a fluorogenic, amine labeling dye that is not fluorescent itself, but covalently reacts with secondary or primary amines to form a fluorescently labeled product. It and other fluorogenic benzofurans (i.e. NBD-Cl) are used for derivitization in HPLC applications. After the fluorogenic reaction, it can be detected with an excitation wavelength of 470 nm (blue) and an emission wavelength of 530 nm (green), enabling an HPLC limit of detection of 10 fmol.
antiparallel The contrasting orientations of the two strands of a double-stranded nucleic acid (and more generally any pair of biopolymers) which are parallel to each other but with opposite directionality. For example, the two complementary strands of a DNA molecule run side-by-side but in opposite directions with respect to chemical numbering conventions, with one strand oriented 5'-to-3' and the other 3'-to-5'.
=== 1982 World's Fair === In 1974, Downtown Knoxville Association president Stewart Evans, following a discussion with King Cole, president of the 1974 Spokane Exposition, raised the possibility of a similar international exposition for Knoxville. Testerman and Tyree both embraced the fair, though the city council and Knoxvillians in general were initially lukewarm to the idea. One key supporter of the fair was rogue banker Jake Butcher, who in 1975 seized control of Knoxville's largest bank, Hamilton National, and shook up the city's conservative banking community. Following his failed gubernatorial campaign in 1978, Butcher turned his attention to the fair initiative, and helped the city raise critical funding. To prepare for the World's Fair, the merged stretch of I-40 and I-75 in West Knoxville was widened, and I-640 was constructed. The old L&N yard along Second Creek, home to a rough neighborhood known as "Scuffletown," was chosen for the fair site, largely for its redevelopment potential. Three hotel chains— Radisson, Hilton, and Holiday Inn— built large hotels in the downtown area in anticipation of the influx of fair visitors. The fair, officially named the International Energy Exposition, was open from May 1 to October 31, 1982, and drew over 11 million visitors. Its success defied the expectations of the Wall Street Journal, which had derided Knoxville as a "scruffy little town," and had predicted the fair would fail.
== Clinical Practice & Patient Care == AMP publishes evidence-based guidelines and freely available reports to provide best practices and recommendations, and to highlight the developments and changing practices in its rapidly evolving field. AMP frequently collaborates with other well-respected professional organizations, such as the College of American Pathologists (CAP), American Society of Clinical Oncology (ASCO), American College of Obstetricians and Gynecologists (ACOG) and American College of Medical Genetics and Genomics (ACMG) to share expertise and broaden the reach of various publications. Guidelines are authored by AMP members elected to the Clinical Practice Committee or appointed by the Board of Directors as subject matter experts to specific working groups.
Sources: en.wikipedia.org
== Structure == In aqueous solutions, glycine exists predominantly as a zwitterion (H3N+CH2COO-), a polar molecule with both a positive and negative charge. The zwitterion form is stabilized by hydrogen bonding with solvent water molecules. Analysis of neutron diffraction data for glycine showed that it was in the zwitterionic form in the solid state and confirmed the presence of hydrogen bonds. Theoretical calculations have been used to show that zwitterions may also be present in the gas phase for some cases different from the simple carboxylic acid-to-amine transfer.
== Biology == SNO-Cap (S-Nitrosocaptopril), a nitrovasodilator Snowcap, a large white area of coloration in horses from the coat patterns of the leopard complex snow-capped manakin (Lepidothrix nattereri), a bird snowcap (Microchera albocoronata), a hummingbird Snowcap, a Sativa-dominant hybrid strain of marijuana, see List of names for cannabis strains
== Indications == Neumega is indicated for the prevention of severe thrombocytopenia and the reduction of the need for platelet transfusions following myelosuppressive chemotherapy in adult patients with nonmyeloid malignancies who are at high risk of severe thrombocytopenia. Efficacy was demonstrated in patients who had experienced severe thrombocytopenia following the previous chemotherapy cycle.
Sources: en.wikipedia.org
=== Nucleotide biosynthesis === Nucleotides serve as the building blocks for nucleic acids, DNA and RNA. They are composed of a nitrogenous base, a pentose sugar, and at least one phosphate group. Nucleotides contain either a purine or a pyrimidine nitrogenous base. All intermediates in purine biosynthesis are constructed on a R5P "scaffold". R5P also serves as an important precursor to pyrimidine ribonucleotide synthesis. During nucleotide biosynthesis, R5P undergoes activation by ribose-phosphate diphosphokinase (PRPS1) to form phosphoribosyl pyrophosphate (PRPP). Formation of PRPP is essential for both the de novo synthesis of purines and for the purine salvage pathway. The de novo synthesis pathway begins with the activation of R5P to PRPP, which is later catalyzed to become phosphoribosylamine, a nucleotide precursor. During the purine salvage pathway, phosphoribosyltransferases add PRPP to bases.
Consider nuclei with a spin of one-half, like 1H, 13C or 19F. Each nucleus has two linearly independent spin states, with m = 1/2 or m = −1/2 (also referred to as spin-up and spin-down, or sometimes α and β spin states, respectively) for the z-component of spin. In the absence of a magnetic field, these states are degenerate; that is, they have the same energy. Hence the number of nuclei in these two states will be essentially equal at thermal equilibrium. If a nucleus with spin is placed in a magnetic field, however, the two states no longer have the same energy as a result of the interaction between the nuclear magnetic dipole moment and the external magnetic field. The energy of a magnetic dipole moment
== Advantages of inlet ionization == Ionization at atmospheric pressure often leads to a loss of ions during the transfer of the ions from the ambient pressure region to the vacuum of the mass analyzer. Ions are lost due to dispersion of analyte spray and 'rim loss' causing fewer ions to reach the vacuum for m/z separation to occur. Initial ionization occurs in the sub-atmospheric pressure region of the heated inlet tube which is directly attached to the vacuum of the mass analyzer and so ion loss is reduced as transfer of the ions does not occur. In LSII the use of the laser increases the image quality of the results by producing better spatial resolution. This is where more pixels are created and so a clearer image is obtained. Multiply charged ions are produced further extending mass range. Multiple methods can be used to fragment molecules producing fragmentation for structural information: electron transfer dissociation (ETD), collision-induced dissociation (CID), and electron capture dissociation (ECD). When using a laser, only small volumes are needed.
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。
It is described as a synthetic analogue of the ACTH(4–10) fragment, a short segment of adrenocorticotropic hormone. Its sequence differs from that fragment and includes two proline residues, which influence stability and behaviour in solution.