neurotrophic factor comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-12-13. Where a claim depends on a specific study, the study is described rather than over-claimed.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular weight | ~813.9 Da (free heptapeptide) | N-acetylated form is about 42 Da heavier |
| Residue count | 7 (heptapeptide) | Four residues from ACTH(4-10), three added |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility class | Freely soluble in water | Also dissolves in DMSO and polar organic solvents |
| Related parent fragment | ACTH(4-10) | Parent motif is Met-Glu-His-Phe |
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。
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
==== Safety audits ==== Safety audits were done every year in the US and European UCC plants, but only every two years in other parts of the world. Before a "Business Confidential" safety audit by UCC in May 1982, the senior officials of the corporation were well aware of "a total of 61 hazards, 30 of them major and 11 minor in the dangerous phosgene/methyl isocyanate units" in Bhopal. In the 1982 audit, it was indicated that worker performance was below standards. Ten major concerns were listed. UCIL prepared an action plan, but UCC never sent a follow-up team to Bhopal. Many of the items in the 1982 report were temporarily fixed, but by 1984, conditions had again deteriorated. In September 1984, an internal UCC report on the West Virginia plant in the United States revealed a number of defects and malfunctions. It warned that "a runaway reaction could occur in the MIC unit storage tanks, and that the planned response would not be timely or effective enough to prevent catastrophic failure of the tanks". This report was never forwarded to the Bhopal plant, although the main design was the same.
== Side effects == Side effects of THC can include red eyes, dry mouth, drowsiness, short-term memory impairment, difficulty concentrating, ataxia, increased appetite, anxiety, paranoia, psychosis (i.e., hallucinations, delusions), decreased motivation, and time dilation, among others. Chronic usage of THC may result in cannabinoid hyperemesis syndrome (CHS), a condition characterized by cyclic nausea, vomiting, and abdominal pain that may persist for months to years after discontinuation.
Other reaction-specific equipment, such as filters for the separation of catalysts, ozone or phosgene generators, can be purchased in many different sizes. The installation of special equipment generally is not a critical path on the overall project for developing an industrial-scale process of a new molecule. Since the mid-1990s, the commercial importance of single-enantiomer fine chemicals has increased steadily. They constitute about half of both existing and developmental drug APIs. In this context, the ability to synthesize chiral molecules has become an important competency. Two types of processes are used: physical separation of the enantiomers and stereo specific synthesis using chiral catalysts. Among the latter, enzymes and synthetic BINAP (2,2'–Bis(diphenylphosphino)–1,1'–binaphthyl) types are used most frequently. Large volume (> 103 mtpa) processes using chiral catalysts include the manufacture of the perfume ingredient l-Menthol, as well as herbicides, such as Syngenta's Dual (metolachlor) and BASF's Outlook (dimethenamid-P). Examples of originator drugs, which apply asymmetric technology, are AstraZeneca's Nexium (esomeprazole) and Merck & Co's Januvia (sitagliptin).
== History == Originally, injectable bulking agents were used to treat stress urinary incontinence in females. The procedure aimed to bulk out the tissues of the neck of the bladder, and it was successful. The technique was first used for FI in 1993 by an Egyptian surgeon. He used polytetrafluroethylene (PTFE/polytef/Teflon) paste injected into the submucosal layer of anal canal. Later publications described autologous transplantation of fat from the abdominal wall or the buttock. After about the year 2000, many different materials started to be used as well as variations of the technique. Some of these materials were concurrently being used to treat urinary incontinence. The latest development of this technique is the implantable bulking agents "Gatekeeper" and "Sphinkeeper". These are not injectable materials but rather implants which expand after placement. As such, they are termed "self-expandable prostheses", and the term "non-self-expandable prostheses" is used to refer to older injectable materials.
The first fossil specimen of the dinosaur later named Sinosauropteryx prima was uncovered in August 1996 by Li Yumin. Yumin was a farmer and part-time fossil hunter who often prospected around Liaoning Province to acquire fossils to sell to individuals and museums. Yumin recognized the unique quality of the specimen, which was separated into two slabs, and sold the slabs to two separate museums in China: the National Geological Museum in Beijing, and the Nanjing Institute of Geology and Paleontology. The director of the Beijing museum, Ji Qiang, recognized the importance of the find, as did visiting Canadian palaeontologist Phil Currie and artist Michael Skrepnick, who became aware of the fossil by chance as they explored the Beijing museum's collections after leading a fossil tour of the area during the first week of October, 1996. Currie recognized the significance of the fossil immediately. As The New York Times quoted him, "When I saw this slab of siltstone mixed with volcanic ash in which the creature is embedded, I was bowled over." When originally described, the authors named Sinosauropteryx, meaning "Chinese Reptilian Wing". Chinese authorities initially barred photographs of the specimen from publication. However, Currie brought a photograph to the 1996 meeting of the Society of Vertebrate Paleontology at the American Museum of Natural History in New York, causing crowds of palaeontologists to gather and discuss the new discovery.
Sources: en.wikipedia.org
{\displaystyle {\text{CL}}\sim {\frac {sV_{e}V_{p}}{sV_{e}+V_{p}}}{\frac {k_{\text{deg}}}{k_{\text{on}}F_{0}}}\left({\frac {{\text{CL}}_{\text{up}}}{V_{e}}}+k_{\text{off}}\right){\frac {F_{0}}{F_{0}-sC_{p}^{\text{IgG}}}}.}
Chia seeds may be added to other foods as a topping or put into smoothies, breakfast cereals, energy bars, granola bars, yogurt, tortillas, and bread. They also may be made into a gelatin-like substance or consumed raw. The gel from ground seeds may be used in place of eggs in baking, and it is a common substitute in vegan and allergen-free baking. Chia seeds can also be used to create a pudding-like dessert if the seeds are mixed with a flavored liquid and left in the fridge overnight. The chia seeds absorb water from the liquid to create a gelatinous outer layer. It is typically made by leaving the seeds to soak in a liquid base overnight.
== Impact == Martin Müller and Alexander Preker, writing for Der Spiegel in January 2024, have referred to Knudsen discovery in inventing the semaglutide weight-loss injections as "revolutionary", with the "drug Wegovy... [having] changed the world", and having "made Novo Nordisk Europe's most valuable company, with a greater market capitalization than Daimler, Bayer, Lufthansa and BMW combined." In the initial clinical trials for Wegovy, diabetics lost more than 10% of their weight and in trials for weight loss, patients lost an average of 12.4% of their weight. Additional patient benefits included reduction of cardiovascular events by 26%, and benefits to patients with heart and kidney failure. The GLP receptor agonists have reformed treatment outcomes for obesity and diabetes "with profound implications for maintaining human health."
=== Insulin resistance === Lower levels of serum valine, like other branched-chain amino acids, are associated with weight loss and decreased insulin resistance: higher levels of valine are observed in the blood of diabetic mice, rats, and humans. Mice fed a BCAA-deprived diet for one day had improved insulin sensitivity, and feeding of a valine-deprived diet for one week significantly decreases blood glucose levels. In diet-induced obese and insulin resistant mice, a diet with decreased levels of valine and the other branched-chain amino acids resulted in a rapid reversal of the adiposity and an improvement in glucose-level control. The valine catabolite 3-hydroxyisobutyrate promotes insulin resistance in mice by stimulating fatty acid uptake into muscle and lipid accumulation. In mice, a BCAA-restricted diet decreased fasting blood glucose levels and improved body composition.
Sources: en.wikipedia.org
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.
Semax is a synthetic analog of the ACTH(4-10) fragment rather than a copy of the full hormone. Truncation plus the added tail removes the steroidogenic portion of ACTH. That distinction explains why it is studied for nervous-system effects instead of adrenal stimulation.
It is registered as a prescription product in Russia and has been used there clinically, chiefly by the intranasal route. No approval exists in the United States or the European Union. Availability elsewhere typically falls under research-chemical distribution, with varying purity documentation.
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.