Semax 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.
Updated 2025-11-07. Numbers and descriptions here follow the published literature rather than marketing material.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
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.
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.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Free acid form of the heptapeptide; depends on terminal groups |
| Molecular mass | About 813.9 g/mol | Average mass used for mass spectrometry confirmation |
| Appearance | White to off-white solid | Supplied as a lyophilised powder; hygroscopic |
| Solubility class | Freely soluble in aqueous media | Water, saline, and phosphate buffers; limited organic solubility |
| Typical storage temperature | -20 degrees Celsius | Long term and dry; short working periods may use 2 to 8 degrees Celsius |
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.
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.
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。
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。
=== Carboxylic acid protecting groups === The most important protecting groups for carboxylic acids are the esters of various alcohols. Occasionally, esters are protected as ortho-esters or oxazolines. Many groups can suffice for the alcoholic component, and the specific cleaving conditions are contrariwise generally quite similar: each ester can be hydrolyzed in a basic water-alcohol solution. Instead, most ester protecting groups vary in how mildly they can be formed from the original acid.
== Side effects == Clinical studies have found that deramciclane is well-tolerated in humans at dosages ranging between 0.2–150 mg. All reported side effects were mild-moderate with the most common side effect being headache and dizziness. No severe side effects were reported in any clinical trial, and no side effects were found to be dose-dependent. Trial participants showed no significant increases in liver enzyme activity and no changes in ECGs, systolic blood pressure, diastolic blood pressure, HDL cholesterol, or LDL cholesterol levels. Another advantage to deramciclane is that it did not produce any withdrawal effects after long-term studies, like other anxiolytics do.
=== Health effects === Research starting in 1975 showed substantially increased risk of endometrial cancer. Since 1976, the drug has carried a label warning about the risk. As part of the Women's Health Initiative sponsored by the National Institutes of Health, a large-scale clinical trial of menopausal HRT showed that long-term use of estrogen and a progestin may increase the risk of strokes, heart attacks, blood clots, and breast cancer. Following these results, Wyeth experienced a significant decline in its sales of Premarin, Prempro (CEEs and medroxyprogesterone acetate), and related products, from over $2 billion in 2002 to just over $1 billion in 2006.
Sources: en.wikipedia.org
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The three substrates of this enzyme are D-glyceraldehyde-3-phosphate, phosphate (Pi), and oxidised nicotinamide adenine dinucleotide (NAD+). Its products are 1,3-bisphosphoglyceric acid, reduced NADH, and a proton. This enzyme participates in glycolysis and gluconeogenesis.
== Alternatives == While being one of the more precise and low-cost protein separation and analysis methods, the SDS-PAGE denatures proteins. Where non-denaturing conditions are necessary, proteins are separated by a native PAGE or different chromatographic methods with subsequent photometric quantification, for example affinity chromatography (or even tandem affinity purification), size exclusion chromatography, ion exchange chromatography. Proteins can also be separated by size in a tangential flow filtration or an ultrafiltration. Single proteins can be isolated from a mixture by affinity chromatography or by a pull-down assay. Some historically early and cost effective but crude separation methods usually based upon a series of extractions and precipitations using kosmotropic molecules, for example the ammonium sulfate precipitation and the polyethyleneglycol precipitation.
Sources: en.wikipedia.org
=== Classification === A clinical severity score has been developed to assess chronic venous ulcers. It is based on the CEAP (clinical, etiology, anatomy, and pathophysiology) classification system developed by an expert panel. A high score gives a poor prognosis.
In 1992, the owner of all Tim Hortons and Wendy's restaurants in Prince Edward Island, Daniel P. Murphy, decided to open new franchise outlets for both brands in the same building in the town of Montague. Murphy invited Joyce and Wendy's chairman Dave Thomas to the grand opening of the "combo store," where the two executives met for the first time. Murphy's success with combining coffee and donuts with Wendy's fast food led to the August 8, 1995, acquisition of and merger with TDL Group by Wendy's International, Inc., an American company; this lasted until 2009. The sale was widely commented on in the media. In 1995, the Toronto Star had a column reflecting on Tim Hortons "selling out" to Wendy's with "the spectacle of another great Canadian icon...gone to Yankee burgerfat".
=== Environment === Many environmental factors will be critical for the welfare and productivity of insect farms. These include: temperature, humidity/moisture, light cycles, oxygen levels, and stocking densities or other spatial features of the environment. For instance, larger cages and specific wavelengths of light are essential for the natural behaviors of adult black soldier fly breeders. Temperature and humidity must be carefully controlled or excess mortality, and putative welfare harms, will result for most insect species. Jagran raises housefly larvae for use as animal feed and report that humidity needs to be carefully controlled to avoid dehydrating or drowning the insects. Insects are poikilothermic, but maintaining an adequate temperature range remains important. For example, lethal overheating is a problem in black soldier fly and yellow mealworm larvae that are reared in dense aggregations within insulating substrates. Although many farmed insects are naturally gregarious, when stocking densities are too high this can cause lethal overheating, increase aggression and cannibalism, or result in altered development and different behavioral needs that may be challenging to fulfill on farms. For instance, some crickets may develop longer wings in an effort to fly far and escape overcrowded conditions on farms; the inability to escape these conditions reduces natural behavioral expression and results in reports of aggression and cannibalism, as stated by one producer: "...they'll bite each other, they'll eat each other".
Sources: en.wikipedia.org
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.
It appears in Russian pharmaceutical listings as a nasal formulation, but it is not an authorised medicine in the United States or the European Union. Outside those markets it is normally encountered as a research chemical rather than a prescription product.
Laboratory and animal work points to melanocortin signalling and changes in neurotrophic factor levels, especially brain-derived neurotrophic factor. The exact receptor targets and the degree to which these findings transfer to humans are still unresolved.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.