A practical reference on semax: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-04-01. Anything still debated is marked as such rather than presented as settled.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
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.
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.
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.
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。
=== Food safety === In 2003, the Codex Alimentarius removed any upper dose limit for food irradiation as well as clearances for specific foods, declaring that all are safe to irradiate. Countries such as Pakistan and Brazil have adopted the Codex without any reservation or restriction. Standards that describe calibration and operation for radiation dosimetry, as well as procedures to relate the measured dose to the effects achieved and to report and document such results, are maintained by the American Society for Testing and Materials (ASTM international) and are also available as ISO/ASTM standards. All of the rules involved in processing food are applied to all foods before they are irradiated.
== Named after Dyson == Dyson conjecture Dyson equation Dyson numbers Dyson operator Dyson series Dyson sphere Dyson tree Dyson's crank Dyson's eternal intelligence Dyson's transform Dyson–Maleev spin wave theory Schwinger–Dyson equation Thue–Siegel–Dyson–Roth theorem Feynman diagram, also known as Dyson graphs Wigner–Yamase–Dyson conjecture Gordon Freeman, a fictional character named after Dyson
=== Separation methods === Few analytical detectors are truly specific for a single species; therefore some type of separation step is often necessary prior to detection. Moreover, separation allows for detection of multiple analytes within a single platform. Separations based upon planar chromatography (TLC) are perhaps the easiest to implement, since many μPADs are constructed with chromatographic paper. Typically, the separation channel is defined by wax-printing two hydrophobic barriers. Electrochemical detection is perhaps most common, likely due to its ease of implementation, although colorimetry, chemiluminscence, and mass spectral detection have also been used in conjunction with paper-based chromatographic separations. Despite the ease of implementation, planar chromatography is hindered by relatively low plate height (i.e., poor separation efficiency). Since the Chakraborty group demonstrated the feasibility of electrokinetic flow on μPADs, several applications of electrophoretic separations on μPADs have appeared in the literature. The Crooks group at UT-Austin successfully demonstrated that electrophoretic separations on μPADs could be accomplished at relatively low applied voltages compared to conventional electrophoretic devices due to the high field strengths that can be generated on very thin (180 μm) sheets of origami paper. Simpler separation methods can also be used on μPADs, for instance, the Henry group demonstrated the separation of plasma from whole blood using blood separation membranes.
Michael Howard Wigler (born September 3, 1947, in New York) is an American molecular biologist who has directed a laboratory at Cold Spring Harbor Laboratory since 1978 and is a member of the National Academy of Sciences. He is best known for developing methods to genetically engineer animal cells and his contributions to cancer, genomics and autism genetics.
=== Thermal === Fluorinated polymers like PTFE and PVDF are especially thermally stable due to strong carbon-fluorine (C–F) bonds, the strongest in organic chemistry, which contribute to the durability of these materials under heat. PVDF is semi-crystalline, giving it a balance of rigidity and flexibility across temperatures from −35 °C to 160 °C. Above 316 °C, PVDF decomposes via dehydrofluorination, which can lead to structural changes, including double bonds and potential discoloration from thermal decomposition.
Sources: en.wikipedia.org
== Structure == β-acrosin demonstrates a high degree of sequence identity (70-80%) between boar, bull, rat, guinea pig, mouse, and human isoforms. There exists a somewhat similar (27-35%) sequence identity between β-acrosin and other serine proteases such as trypsin and chymotrypsin. While most serine proteases are activated through one cleavage event, proacrosin requires processing at both the N and C-terminal domains. Proacrosin is first cleaved between Arg-22 and adjacent Valine to create a 22 residue light chain, and an active protease termed α-acrosin. This light chain remains associated with the heavy chain, cross-linked through two disulfide bonds to form a heterodimer. Following these N-terminal cleavage events, three cleavages at the C-terminal domain removes 70 residues, yielding β-acrosin. Acrosin has two sites which have been identified as possible N-glycosylation sites: Asn-2 and Asn-169. The catalytic triad consists of residues His-57, Asp-102, and Ser-195. These residues are found in a binding pocket that has been termed the "S1" pocket, consistent with the naming scheme that has been adopted for other proteases. The S1 pocket regulates acrosin's specificity for Arg and Lys substrates, with a conserved Trp-215 serving as a "gatekeeper" residue for the binding site entrance.
For example, because of this trend in the sizes of orbitals, a large difference in atomic radii between the first and second members of each main group is seen in groups 1 and 13–17: it exists between neon and argon, and between helium and beryllium, but not between helium and neon. This similarly affects the noble gases' boiling points and solubilities in water, where helium is too close to neon, and the large difference characteristic between the first two elements of a group appears only between neon and argon. Moving helium to group 2 makes this trend consistent in groups 2 and 18 as well, by making helium the first group 2 element and neon the first group 18 element: both exhibit the characteristic properties of a kainosymmetric first element of a group. The group 18 placement of helium nonetheless remains near-universal due to its extreme inertness. Additionally, tables that float both hydrogen and helium outside all groups may rarely be encountered.
=== Demographic === Gender, age, ethnicity, life expectancy, longevity, population density, and community diversity are all demographic characteristics that can increase the risk and severity of mental disorders.
In 1953, he married American actress and singer Gloria DeHaven. They divorced in 1954. His second marriage was to Claudia Aronow, a New York artist and daughter of boat designer and racer Donald Aronow. They later divorced. They had one son together, menswear designer Adam Kimmel who is married to the actress Leelee Sobieski. His third marriage was to Helen Lyttle. In addition, Kimmel has several stepchildren: stepdaughter Betsy Karel of Washington; stepdaughter Abby Leigh of Manhattan; and stepson Alexei Hay of Manhattan. Kimmel was a member of Temple Emanu-El in New York City. Kimmel died April 15, 2008. In November 2008, his wife Helen donated $150 million toward construction of a new patient pavilion at the NYU Langone Medical Center in honor of her late husband.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.