If you have been reading about semax and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-09-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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 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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
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。
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
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.
== Roles in disease and medicine == It has been found to have anticarcinogenic properties. In a study on mice, injecting a preparation of DSIP over the mice's lifetime decreased total spontaneous tumor incidence 2.6-fold. The same study found it to also have geroprotective effects: it slowed down the age-related switching-off of oestrous function; it decreased by 22.6% the frequency of chromosome aberrations in bone marrow cells and it increased by 24.1% maximum life span in comparison with the control group. Levels of DSIP may be significant in patients diagnosed with major depressive disorder (MDD). In several studies, levels of DSIP in the plasma and cerebrospinal fluid are significantly deviated from the norm in patients with MDD, though there are contradictions as to whether levels are higher or lower than healthy control patients. Studies have demonstrated a direct link between GILZ expression (homologous to DSIP) and adipogenesis which has links to obesity and metabolic syndrome. In studies on rats with metaphit-induced epilepsy DSIP acted as an anticonvulsant, significantly decreasing the incidence and duration of fits suggesting DSIP as a potential treatment for epilepsy. DSIP has been found to have an analgesic effect. In studies on mice it was found to have a potent antinociceptive effect when administered intracerebroventricularly or intracisternally (see: Route of administration). Due to its possible effects on sleep and nociception, trials have been carried out to determine whether DSIP can be used as an anaesthetic.
IGOs are established by a treaty that acts as a charter creating the group. Treaties are formed when lawful representatives (governments) of several states go through a ratification process, providing the IGO with an international legal personality. Intergovernmental organizations are an important aspect of public international law. Intergovernmental organizations in a legal sense should be distinguished from simple groupings or coalitions of states, such as the G7 or the Quartet. Such groups or associations have not been founded by a constituent document and exist only as task groups. Intergovernmental organizations must also be distinguished from treaties. Many treaties (such as the North American Free Trade Agreement, or the General Agreement on Tariffs and Trade before the establishment of the World Trade Organization) do not establish an independent secretariat and instead rely on the parties for their administration, for example by setting up a joint committee. Other treaties have established an administrative apparatus which was not deemed to have been granted binding legal authority. The broader concept wherein relations among three or more states are organized according to certain principles they hold in common is multilateralism.
Plants rely on micronutrients to build many essential proteins. In fact, every process that supports the growth of a plant is mediated by some protein which contains one of the many micronutrients. For example, Mn is an essential micronutrient for many plants because it builds the structure of photosystem II which splits water molecules to harness energy from electrons. Inadequate micronutrient uptake can result in deficiencies and even mortality in extreme cases. Alternatively, elevated concentrations of micronutrients in soils can result in toxicity.
== Discovery == An in silico search for potential small open-reading-frames (sORFs) within 16S ribosomal RNA-encoding short peptides (20–40 amino acids) was conducted in the Pinchas Cohen lab at University of Southern California. Six sequences encoding 20–38 amino-acid-long peptides were identified, which were named SHLP 1–6. The endogenous SHLPs were detected by immunoblots and their transcripts were validated by both qPCR and northern blot.
Sources: en.wikipedia.org
The Pantheon of Skeptics was created by CSI to remember the legacy of deceased fellows of CSI and their contributions to the cause of scientific scepticism. A sculpted bust of Francis Crick by John Sherrill Houser, which incorporates a single "Golden" Helix, was cast in bronze in the artist's studio in New Mexico, US. The bronze was first displayed at the Francis Crick Memorial Conference (on Consciousness) at Churchill College, Cambridge on 7 July 2012; it was bought by Mill Hill School in May 2013, and displayed at the inaugural Crick Dinner on 8 June 2013, and was again at their Crick Centenary Dinner in 2016. The Benjamin Franklin Medal for Distinguished Achievement in the Sciences of the American Philosophical Society (2001), together with Watson. Crick featured in the BBC Radio 4 series The New Elizabethans to mark the Diamond Jubilee of Elizabeth II in 2012. A panel of seven academics, journalists and historians named Crick among a group of 60 people in the UK "whose actions during the reign of Elizabeth II have had a significant impact on lives in these islands and given the age its character".
==== MeSH D13.695.827 – ribonucleotides ==== MeSH D13.695.827.068 – adenine nucleotides MeSH D13.695.827.068.124 – adenosine diphosphate MeSH D13.695.827.068.124.070 – adenosine diphosphate sugars MeSH D13.695.827.068.124.070.075 – adenosine diphosphate glucose MeSH D13.695.827.068.124.070.125 – adenosine diphosphate ribose MeSH D13.695.827.068.124.070.125.040 – o-acetyl-adp-ribose MeSH D13.695.827.068.124.070.125.195 – cyclic adp-ribose MeSH D13.695.827.068.180 – adenosine monophosphate MeSH D13.695.827.068.180.080 – adenosine phosphosulfate MeSH D13.695.827.068.236 – adenosine triphosphate MeSH D13.695.827.068.236.050 – adenylyl imidodiphosphate MeSH D13.695.827.068.236.250 – ethenoadenosine triphosphate MeSH D13.695.827.068.309 – clofarabine MeSH D13.695.827.068.382 – coenzyme a MeSH D13.695.827.068.382.300 – acyl coenzyme a MeSH D13.695.827.068.382.300.020 – acetyl coenzyme a MeSH D13.695.827.068.382.300.500 – malonyl coenzyme a MeSH D13.695.827.068.382.300.700 – palmitoyl coenzyme a MeSH D13.695.827.068.395 – cyclic amp MeSH D13.695.827.068.395.225 – 8-bromo cyclic adenosine monophosphate MeSH D13.695.827.068.395.250 – bucladesine MeSH D13.695.827.068.506 – flavin-adenine dinucleotide MeSH D13.695.827.068.694 – nad MeSH D13.695.827.068.749 – nadp MeSH D13.695.827.068.850 – phosphoadenosine phosphosulfate MeSH D13.695.827.232 – cytosine nucleotides MeSH D13.695.827.232.115 – cyclic cmp MeSH D13.695.827.232.150 – cytidine diphosphate MeSH D13.695.827.232.150.180 – cytidine diphosphate choline MeSH D13.695.827.232.150.210 – cytidine diphosphate diglycerides MeSH D13.695.827.232.370 – cytidine monophosphate MeSH D13.695.827.232.370.250 – cytidine monophosphate n-acetylneuraminic acid MeSH D13.695.827.232.400 – cytidine triphosphate MeSH D13.695.827.349 – flavin mononucleotide MeSH D13.695.827.426 – guanine nucleotides MeSH D13.695.827.426.160 – cyclic gmp MeSH D13.695.827.426.160.325 – dibutyryl cyclic gmp MeSH D13.695.827.426.340 – guanosine diphosphate MeSH D13.695.827.426.340.350 – guanosine diphosphate sugars MeSH D13.695.827.426.340.350.400 – guanosine diphosphate fucose MeSH D13.695.827.426.340.350.500 – guanosine diphosphate mannose MeSH D13.695.827.426.400 – guanosine monophosphate MeSH D13.695.827.426.440 – guanosine pentaphosphate MeSH D13.695.827.426.480 – guanosine tetraphosphate MeSH D13.695.827.426.504 – guanosine triphosphate MeSH D13.695.827.426.504.380 – guanosine 5'-o-(3-thiotriphosphate) MeSH D13.695.827.426.504.400 – guanylyl imidodiphosphate MeSH D13.695.827.426.700 – rna caps MeSH D13.695.827.426.700.710 – rna cap analogs MeSH D13.695.827.519 – inosine nucleotides MeSH D13.695.827.519.300 – cyclic imp MeSH D13.695.827.519.400 – inosine diphosphate MeSH D13.695.827.519.500 – inosine monophosphate MeSH D13.695.827.519.800 – inosine triphosphate MeSH D13.695.827.648 – nicotinamide mononucleotide MeSH D13.695.827.708 – nucleoside diphosphate sugars MeSH D13.695.827.708.070 – adenosine diphosphate sugars MeSH D13.695.827.708.070.075 – adenosine diphosphate glucose MeSH D13.695.827.708.070.125 – adenosine diphosphate ribose MeSH D13.695.827.708.070.125.040 – o-acetyl-adp-ribose MeSH D13.695.827.708.070.125.195 – cyclic adp-ribose MeSH D13.695.827.708.070.125.600 – poly adenosine diphosphate ribose MeSH D13.695.827.708.260 – cytidine diphosphate diglycerides MeSH D13.695.827.708.400 – guanosine diphosphate sugars MeSH D13.695.827.708.400.410 – guanosine diphosphate fucose MeSH D13.695.827.708.400.500 – guanosine diphosphate mannose MeSH D13.695.827.708.727 – uridine diphosphate sugars MeSH D13.695.827.708.727.100 – uridine diphosphate n-acetylgalactosamine MeSH D13.695.827.708.727.120 – uridine diphosphate n-acetylglucosamine MeSH D13.695.827.708.727.150 – uridine diphosphate n-acetylmuramic acid MeSH D13.695.827.708.727.300 – uridine diphosphate galactose MeSH D13.695.827.708.727.350 – uridine diphosphate glucose MeSH D13.695.827.708.727.375 – uridine diphosphate glucuronic acid MeSH D13.695.827.708.727.800 – uridine diphosphate xylose MeSH D13.695.827.919 – uracil nucleotides MeSH D13.695.827.919.600 – uridine diphosphate MeSH D13.695.827.919.600.677 – uridine diphosphate sugars MeSH D13.695.827.919.600.677.100 – uridine diphosphate n-acetylgalactosamine MeSH D13.695.827.919.600.677.120 – uridine diphosphate n-acetylglucosamine MeSH D13.695.827.919.600.677.150 – uridine diphosphate n-acetylmuramic acid MeSH D13.695.827.919.600.677.300 – uridine diphosphate galactose MeSH D13.695.827.919.600.677.350 – uridine diphosphate glucose MeSH D13.695.827.919.600.677.375 – uridine diphosphate glucuronic acid MeSH D13.695.827.919.600.677.800 – uridine diphosphate xylose MeSH D13.695.827.919.877 – uridine monophosphate MeSH D13.695.827.919.877.500 – sofosbuvir MeSH D13.695.827.919.950 – uridine triphosphate
=== Steel contamination === Cobalt is found in steel. Uncontrolled disposal of 60Co in scrap metal is responsible for the radioactivity in some iron products. Circa 1983, construction was finished of 1700 apartments in Taiwan which were built with steel contaminated with cobalt-60. About 10,000 people occupied these buildings during a 9–20 year period. On average, these people unknowingly received a radiation dose of 0.4 Sv. Some studies have found that this large group did not suffer a higher incidence of cancer mortality, as the linear no-threshold model would predict, but suffered a lower cancer mortality than the general Taiwan public. These observations support the radiation hormesis model, however other studies have found health impacts that confound the results. In August 2012, Petco recalled several models of steel pet food bowls after US Customs and Border Protection determined that they were emitting low levels of radiation, which was determined to be from 60Co that had contaminated the steel. In May 2013, a batch of metal-studded belts sold by online retailer ASOS were confiscated and held in a US radioactive storage facility after testing positive for 60Co.
== Research == SGLT2 inhibitors increase circulating ketone body concentrations. The cardioprotective effects of SGLT2 inhibitors have been attributed to the elevated ketone levels. Gliflozins have been posited to exhibit protective effects on the heart, liver, kidneys, anti‐hyperlipidemic, anti‐atherosclerotic, anti‐obesity, anti‐neoplastic effects in in vitro, pre‐clinical, and clinical studies. Pleiotropic effects of this class have been attributed to a variety of its pharmacodynamic actions such as natriuresis, hemoconcentration, deactivation of renin–angiotensin–aldosterone system, ketone body formation, alterations in energy homeostasis, glycosuria, lipolysis, anti‐inflammatory, and antioxidative actions. SGLT2 inhibitors have shown beneficial effects on liver function in clinical trials on individuals with NAFLD and type 2 diabetes, and also on those without type 2 diabetes. SGLT2 inhibitors also modified the adverse effects of ozone in heart failure, indicating a potential cardioprotective role. SGLT2 inhibitors have anti-inflammatory and immunomodulatory effects through pathways such as NF-κB, AMPK/mTOR, and JAK/STAT.
The Subsecretariat of Alternative Development and Substitution of Coca Cultivation (Subsecretaría de Desarrollo Alternativo y Sustitución de Cultivos de Coca) and its Coca Eradication Directorate (Dirección de la Reconversión de la Coca—Direco) were charged with drawing up overall rural development plans for the areas affected by the substitution of the coca plantations. On July 19, 1988, to qualify for United States aid, Paz Estenssoro signed the Law of Regulations for Coca and Controlled Substances (Ley del Régimen de la Coca y Sustancias Controladas)- -hereafter, the 1988 Antinarcotics Law. One of the strictest antinarcotics laws in Latin America, it aimed at eradicating illicit coca production and penalizing trafficking in drugs. As enacted by presidential decree in December 1988, the new law provided for a 10,000-hectare zone of legal coca cultivation in the Yungas region of La Paz Department and a small section of Cochabamba Department to meet traditional demand (down from a previous total of 80,000 hectares for the Yungas and Chapare regions). It also provided for a transitional zone of excess production in the Chapare region subject to annual reduction bench marks of 5,000 to 8,000 hectares and provided for an illegal zone, comprising all territory outside the traditional and transitional areas, in which coca cultivation was prohibited.
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
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.