en · de · es
semax-notes.peptides3626.com › News › Semax Background And Molecular Structure — Complete Guide

Semax Background And Molecular Structure — Complete Guide

By Editorial Desk · published 2025-06-29 · last reviewed 2025-08-21 · News

This is a working overview of semax, written for readers who want more than a one-paragraph summary but less than a textbook.

This page was last updated on 2025-08-21 and is reviewed periodically as new material appears.

Semax Background and Molecular Structure

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.

The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.

Semax Peptide Structure and Origin

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.

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.

Semax at a glance

PropertyValueNotes
Molecular weight~813.9 Da (free heptapeptide)N-acetylated form is about 42 Da heavier
Residue count7 (heptapeptide)Four residues from ACTH(4-10), three added
AppearanceWhite to off-white powderUsually supplied lyophilized
Solubility classFreely soluble in waterAlso dissolves in DMSO and polar organic solvents
Related parent fragmentACTH(4-10)Parent motif is Met-Glu-His-Phe

Semax Origin and Molecular Structure

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.

Related pages on this site

Background and Development History

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.

Semax Structure and Research Background

Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.

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.

Semax 的分子背景与结构

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。

Reference notes

==== MeSH D12.125.740 – phosphoamino acids ==== MeSH D12.125.740.025 – 2-amino-5-phosphonovalerate MeSH D12.125.740.675 – phosphocreatine MeSH D12.125.740.700 – phosphoserine MeSH D12.125.740.725 – phosphothreonine MeSH D12.125.740.740 – phosphotyrosine

Consumers yield isotopic signatures that reflect the sulfur reservoir(s) of the dietary protein source. Animal proteins sourced from marine ecosystems tend to have δ34S values between +16 and +17‰, terrestrial plants range from -7‰ to +8‰, while proteins from freshwater and terrestrial ecosystems are highly variable. The sulfate content of the modern ocean is well-mixed with a δ34S of approximately +21‰, while riverine water is heavily influenced by sulfur-bearing minerals in surrounding bedrock and terrestrial plants are influenced by the sulfur content of local soils. Estuarian ecosystems have increased complexity due to seawater and river inputs. The extreme range of δ34S values for freshwater ecosystems often interferes with terrestrial signals, making it difficult to use the sulfur system as the sole tool in paleodiet studies. Various studies have analyzed the isotopic ratios of sulfur in mummified hair. Hair is a good candidate for sulfur studies as it typically contains at least 5% elemental sulfur. One study incorporated sulfur isotope ratios into their paleodietary investigation of four mummified child victims of Incan sacrificial practices. δ34S values helped them conclude that the children had not been eating marine protein before their death. Historical insight coupled with consistent sulfur signatures for three of the children suggests that they were living in the same location 6 months prior to the sacrifice.

=== Selective mode and scanning mode === Ions are either injected into or created within the interior of the LIT. They are confined by application of appropriate RF and DC voltages with their final position maintained within the center section of the LIT. The RF voltage is adjusted and multi-frequency resonance ejection waveforms are applied to the trap to eliminate all but the desired ions in preparation for subsequent fragmentation and mass analysis. The voltages applied to the ion trap are adjusted to stabilize the selected ions and to allow for collisional cooling in preparation for excitation. The energy of the selected ions is increased by application of a supplemental resonance excitation voltage applied to all segments of two rods located on the X-axis. This increase of energy causes dissociation of the selected ions due to collisions with damping gas. The product ions formed are retained in the trapping field. Scanning the contents of the trap to produce a mass spectrum is accomplished by linearly increasing the RF voltage applied to all sections of the trap and utilizing a supplemental resonance ejection voltage. These changes sequentially move ions from within the stability diagram to a position where they become unstable in the x-direction and leave the trapping field for detection. Ions are accelerated into two high voltage dynodes where ions produce secondary electrons. This signal is subsequently amplified by two electron multipliers and the analog signals are then integrated together and digitized.

As of 2019, AAV vectors have been used in over 250 clinical trials worldwide, approximately 8.3% of virus-vectored gene-therapy trials. Recently, promising results have been obtained from Phase 1 and Phase 2 trials for a number of diseases, including Leber's congenital amaurosis, hemophilia, congestive heart failure, spinal muscular atrophy, lipoprotein lipase deficiency, and Parkinson's disease. AAV based gene therapy products have entered the worldwide market following completion of successful clinical trials. The table below contains FDA approved gene therapies that have entered the American Market and possibly other markets.

An important use of 237Np is as a precursor in plutonium-238 production, where it is irradiated with neutrons to form 238Pu, an alpha emitter for radioisotope thermal generators for spacecraft and military applications. 237Np will capture a neutron to form 238Np and beta decay with a half-life of just over two days to 238Pu.

Sources: en.wikipedia.org

Notes from published material

== Efficacy == Being a dual PPAR agonist, saroglitazar helps in controlling blood glucose and lipid parameters, especially high triglycerides and high non-HDL cholesterol. A study done in rats concluded that saroglitazar has the potential to prevent the progression of retinopathy in diabetes patients. Using preclinical models, it has also been shown to be useful in diabetic nephropathy.

The commission noted that such incidents in July and August 2008 "could no longer be countered by the JPKF" and "reactivating the peacekeeping mechanism was not an alternative means of redress available for Georgia." It also noted that Georgian attack on Tskhinvali on 7 August was a response, albeit not proportionate, to South Ossetian attacks in the following paragraphs:

=== Complications === A number of complications may occur, with infections being the most common. In order of frequency, potential complications include: pneumonia, cellulitis, urinary tract infections and respiratory failure. Risk factors for infection include: burns of more than 30% TBSA, full-thickness burns, extremes of age (young or old), or burns involving the legs or perineum. Pneumonia occurs particularly commonly in those with inhalation injuries. Anemia secondary to full thickness burns of greater than 10% TBSA is common. Electrical burns may lead to compartment syndrome or rhabdomyolysis due to muscle breakdown. Blood clotting in the veins of the legs is estimated to occur in 6 to 25% of people. The hypermetabolic state that may persist for years after a major burn can result in a decrease in bone density and a loss of muscle mass. Keloids may form subsequent to a burn, particularly in those who are young and dark skinned. Following a burn, children may have significant psychological trauma and experience post-traumatic stress disorder. Scarring may also result in a disturbance in body image. To treat hypertrophic scars (raised, tense, stiff and itchy scars) and limit their effect on physical function and everyday activities, silicone sheeting and compression garments are recommended. In the developing world, significant burns may result in social isolation, extreme poverty and child abandonment.

The more serious resistance in the départements was crushed by declaring a state of siege and by the "mixed commissions". The plebiscite of 20 December ratified by a huge majority the coup d'état in favour of the prince-president, who alone reaped the benefit of the excesses of the Republicans and the reactionary passions of the monarchists.

Sources: en.wikipedia.org

Background from the literature

The Five Guys menu focuses on hamburgers offered with Kraft American cheese or applewood-smoked bacon and kosher style hot dogs (Hebrew National all-beef franks), as well as grilled cheese, BLT and vegetable sandwiches. Five Guys uses buns that are sweeter and "eggier" than normal buns. The hamburgers come in two sizes: regular (two patties) and little (one patty). Customers may select from 15 toppings at no charge. Fresh-cut french fries are the sole side item, available salted only in "Five Guys style" or seasoned "Cajun style". Conventionally, Five Guys employees are directed to give customers an extra scoop of fries for free when they order. The rationale was to persuade the customer that they were getting a good deal by giving them more fries than they'd paid for. However, the extras were already accounted for in the initial pricing. Complimentary roasted in-shell peanuts are offered for on-site consumption at most locations, with signage alerting potential customers who may have a peanut allergy; for these allergen reasons, customers are not allowed to take peanuts off-site.

=== Ubiquitination and role in development === Cereblon forms an E3 ubiquitin ligase complex with damaged DNA binding protein 1 (DDB1), cullin-4A (CUL4A), and regulator of cullins 1 (ROC1). This complex ubiquitinates a number of other proteins and marks them for degradation via the proteasome. Through a mechanism which has not been completely elucidated, this ubiquitination results in reduced levels of fibroblast growth factor 8 (FGF8) and fibroblast growth factor 10 (FGF10). FGF8 in turn regulates a number of developmental processes, such as limb and auditory vesicle formation. The net result is that this ubiquitin ligase complex is important for limb outgrowth in embryos. At the molecular level, C-terminal cyclic imides have been identified as endogenous degrons recognized by cereblon. Cyclic imides can arise through spontaneous peptide-bond cleavage at asparagine or glutamine residues in aging proteins, and have long been observed in proteins such as α-crystallin. In 2022, C-terminal aspartimide and aminoglutarimide residues were shown to bind the thalidomide-binding domain of cereblon and to function as degrons promoting CRBN-dependent ubiquitination and proteasomal degradation. In the absence of cereblon, DDB1 forms a complex with DDB2 that functions as a DNA damage-binding protein. Furthermore, cereblon and DDB2 bind to DDB1 in a competitive manner.

=== Role in synchronized fertilization on dairy farms === By using cows that produce offspring within a one to two-week period, synchronized breeding allows dairy farmers to artificially inseminate cows for maximum pregnancy rates with minimal effort. BST is a placental lactogen (PL) hormone and falls under the class of growth hormone, or somatotropin. It is relevant to the practice of artificially expediting placental development in farm mammals, specifically dairy cattle. The mechanism through which the hormones of this somatotropin exert their effects can be observed at the cellular and molecular level in placental tissue. For mammals exposed to the hormone, bovine somatotropin associates with N-glycosylated proteins that are heavily involved in placental gestation. Knowledge of this and how BST works in conjunction with growth hormones allows for agricultural researchers to experiment on the effects of synchronization in farm animals. Synchronization involves treating cattle with a dose of BST before artificially inseminating them, according to a fixed interval schedule. Synchronization and BST treatment may be used to increase first-service pregnancy rates while following this timed artificial insemination protocol. This would therefore allow agricultural researchers to observe the effects of hormones in relation to natural estrous cycles. Dairy cattle experienced increased rates of pregnancy during synchronization when exposed to BST.

=== Early Meiji period (1868–77) === In 1854, after US Navy Commodore Matthew C. Perry forced the signing of the Treaty of Kanagawa, Japanese elites took the position that they needed to modernize the state's military capacities, or risk further coercion from Western powers, just as Qing China did in the First Opium War.

== GSNOR == The enzyme GSNO reductase (GSNOR) reduces S-nitrosoglutathione (GSNO) to an unstable intermediate, S-hydroxylaminoglutathione, which then rearranges to form glutathione sulfonamide, or in the presence of GSH, forms glutathione disulfide and hydroxylamine.

Sources: en.wikipedia.org

Frequently asked questions

What is the amino acid sequence of Semax?

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.

How does Semax relate to ACTH?

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.

Is Semax an approved medicine?

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.

What is Semax chemically?

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.

Network