Semax raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-05-13 and is reviewed periodically as new material appears.
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。
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 is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
| 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. 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.
The calcium ion concentration in the cytosol of the beta cells can also, or additionally, be increased through the activation of phospholipase C resulting from the binding of an extracellular ligand (hormone or neurotransmitter) to a G protein-coupled membrane receptor. Phospholipase C cleaves the membrane phospholipid, phosphatidyl inositol 4,5-bisphosphate, into inositol 1,4,5-trisphosphate and diacylglycerol. Inositol 1,4,5-trisphosphate (IP3) then binds to receptor proteins in the plasma membrane of the endoplasmic reticulum (ER). This allows the release of Ca2+ ions from the ER via IP3-gated channels, which raises the cytosolic concentration of calcium ions independently of the effects of a high blood glucose concentration. Parasympathetic stimulation of the pancreatic islets operates via this pathway to increase insulin secretion into the blood. The significantly increased amount of calcium ions in the cells' cytoplasm causes the release into the blood of previously synthesized insulin, which has been stored in intracellular secretory vesicles. This is the primary mechanism for release of insulin. Other substances known to stimulate insulin release include the amino acids arginine and leucine, parasympathetic release of acetylcholine (acting via the phospholipase C pathway), sulfonylurea, cholecystokinin (CCK, also via phospholipase C), and the gastrointestinally derived incretins, such as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP).
Volufralin (INNTooltip International Nonproprietary Name; developmental code names LIB-01, DIC-2024, and Libiguin) is an indirect melanocortin MC4 receptor potentiator which is under development for the treatment of erectile dysfunction and premature ejaculation. It is taken orally.
A cDNA for this reductase has been cloned from the orchid Bromheadia finlaysoniana. Researchers in Japan have genetically manipulated roses by using RNA interference to knock out the endogenous enzyme and add a gene for an alternative reductase found in an iris; or add a gene for the blue pigment, delphinidin, to create a blue rose, which is being sold worldwide. Dihydrokaempferol 4-reductase is also an enzyme on the lignin biosynthesis pathway. In Arabidopsis thaliana, the enzyme uses sinapaldehyde or coniferyl aldehyde or coumaraldehyde to produce sinapyl alcohol or coniferyl alcohol or coumaryl alcohol respectively.
Sources: en.wikipedia.org
Sutherland and colleagues have proposed that phosphorimidazolides may have formed in the chemical environment of early Earth via the activation of ribonucleotide phosphates by methyl isocyanaide and acetaldehyde followed by substitution with imidazole.
For patients who are exposed to lithium, or plan to stay on the medication throughout their pregnancy, fetal echocardiography is routinely performed to monitor for cardiac anomalies. Pregnancy is associated with a decrease in blood lithium levels (especially in the first and second trimesters), so more frequent monitoring with an increase in dose may be required to maintain control of symptoms. To prevent postpartum psychosis, a higher blood lithium level may be desirable in the third trimester. Initiating lithium immediately after delivery is also effective for preventing postpartum psychosis and postpartum bipolar relapse. This is an acceptable treatment option for women with a history of psychosis limited to the postpartum period. For women with diagnosed bipolar disorder, this provides less protection than maintaining lithium therapy during pregnancy.
'Mayleen (pale pink) Clematis montana var. grandiflora (white) Clematis montana var. rubens 'Tetrarose' (rose pink with green stamens) In the Clematis viticella group (or Viticella group) are compact deciduous climbers with small flowers produced on the current year's growth, such as:
Sources: en.wikipedia.org
== Research == Observational studies suggested an inverse correlation between a higher intake of vitamin B6 and all cancers, with the strongest evidence for gastrointestinal cancers. However, evidence from a review of randomized clinical trials did not support a protective effect. The authors noted that high B6 intake may be an indicator of higher consumption of other dietary protective micronutrients. A review and two observational trials reporting lung cancer risk reported that serum vitamin B6 was lower in people with lung cancer compared to people without lung cancer, but did not incorporate any intervention or prevention trials. According to a prospective cohort study the long-term use of vitamin B6 from individual supplement sources at greater than 20 mg per day, which is more than ten times the adult male RDA of 1.7 mg/day, was associated with an increased risk for lung cancer among men. Smoking further elevated this risk. However, a more recent review of this study suggested that a causal relationship between supplemental vitamin B6 and an increased lung cancer risk cannot be confirmed yet. For coronary heart disease, a meta-analysis reported lower relative risk for a 0.5 mg/day increment in dietary vitamin B6 intake. As of 2021, there were no published reviews of randomized clinical trials for coronary heart disease or cardiovascular disease. In reviews of observational and intervention trials, neither higher vitamin B6 concentrations nor treatment showed any significant benefit on cognition and dementia risk.
== Bibliography == Biko, Steve (1979). Steve Biko: Black Consciousness in South Africa; Biko's Last Public Statement and Political Testament. Random House. ISBN 978-0-394-72739-4. Biko, Steve (2002). I Write What I Like: Selected Writings. University of Chicago Press. ISBN 978-0-226-04897-0. Clarke, Anthony J.; Fiddes, Paul S., eds. (2005). Flickering Images: Theology and Film in Dialogue. Regent's Study Guides. Vol. 12. Macon, GA: Smyth & Helwys Publishing. ISBN 1-57312-458-3. Goodwin, June (1995). Heart of Whiteness: Afrikaners Face Black Rule In the New South Africa. Scribner. ISBN 978-0-684-81365-3. Harlan, Judith (2000). Mamphela Ramphele. The Feminist Press at CUNY. ISBN 978-1-55861-226-6. Juckes, Tim (1995). Opposition in South Africa: The Leadership of Z. K. Matthews, Nelson Mandela, and Stephen Biko. Praeger Publishers. ISBN 978-0-275-94811-5. Magaziner, Daniel (2010). The Law and the Prophets: Black Consciousness in South Africa, 1968–1977. Ohio University Press. ISBN 978-0-8214-1918-2. Malan, Rian (2000). My Traitor's Heart: A South African Exile Returns to Face His Country, His Tribe, and His Conscience. Grove Press. ISBN 978-0-8021-3684-8. Omand, Roger (1989). Steve Biko and Apartheid (People & Issues). Hamish Hamilton Limited. ISBN 978-0-241-12640-0. Paul, Samuel (2009). The Ubuntu God: Deconstructing a South African Narrative of Oppression. Pickwick Publications. ISBN 978-1-55635-510-3. Pityana, Barney (1992). Bounds of Possibility: The Legacy of Steve Biko & Black Consciousness. D. Philip. ISBN 978-1-85649-047-4. Price, Linda (1992).
== History == Properdin was discovered in 1954 by Dr. Louis Pillemer of the Institute of Pathology (now the Department of Pathology at Case Western Reserve University). He was an American immunologist and investigated the complement system, a system of defense not dependent upon antibodies. At Case Western, he was the first to purify tetanus and dipheria toxins, which were used to develop the DPT vaccine. The complement system was discovered more than 100 years ago, when experiments proved that lysing of microbial targets could be induced by a "complementary" mixture of human serum and antibody mixtures. The alternative pathway was discovered when Dr. Louis Pillemer observed partial purification of the plasma protein properdin, and its ability to activate the complement system on various targets without using antibodies. In the 1970's, evidence was found of an antibody-independent complement activation pathway. Protein purification methods were utilized to model complement activation, such as the alternative pathway C3 convertase.
is referred to as the chi plot. For flat surfaces, the slope of the chi plot yields the surface area. Empirically, this plot was noticed as being a very good fit to the isotherm by Michael Polanyi and also by Jan Hendrik de Boer and Cornelis Zwikker but not pursued. This was due to criticism in the former case by Albert Einstein and in the latter case by Brunauer. This flat surface equation may be used as a "standard curve" in the normal tradition of comparison curves, with the exception that the porous sample's early portion of the plot of
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。
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.