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 2026-02-16 and is reviewed periodically as new material appears.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
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.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
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.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
=== By choosing the best age === Because of the intrinsic uncertainties within the three yield U-Pb ages (207Pb/235U, 206Pb/238U and 207Pb/206Pb), the age at ~1.4 Ga has the poorest resolution. An overall consensus for age with higher accuracy is to adopt:
== Adverse effects == Although the absorption of betamethasone dipropionate is small, when used for prolonged periods of time (periods exceeding two weeks), or across a large surface area (total use greater than 50 grams per week), it can have adverse effects. One such effect is the ability of the corticosteroid to suppress the hypothalamic–pituitary–adrenal axis. This can lead to a depression in the release of adrenal hormones such as cortisol and adrenocorticotropic hormone, or ACTH. Symptoms of HPA axis suppression are often subtle and variable, but can often be detected using simple blood or urine tests such at ACTH stimulation test or urinary free cortisol. Those at increased risk for HPA axis suppression are those who are more likely to absorb more of the steroid through the skin. These groups include:
== Side effects == Patients, physicians and researchers say usual, expected side effects include; temporary redness, pain and tenderness during injections and swelling and bruising at the injection sites. The more serious side effects include: immune system reactions which result in facial lumps and bumps known as granulomas, bothersome reactions which are very difficult for physicians to treat. According to Allergan, Juvéderm should not be used in patients with severe allergies, particularly those who have allergies to bacterial proteins or patients with a history of anaphylaxis, which is a potentially life-threatening hypersensitivity to some drugs and proteins.
Aristotle is saying that at this stage the body is still growing; it is best for sexual activity to begin when its growth is 'no longer abundant', for when the body is more or less at full height, the transformation of nourishment into semen does not drain the body of needed material." Additionally, "Aristotle tells us that the region round the eyes was the region of the head most fruitful of seed ("most seedy" σπερματικώτατος), pointing to generally recognised effects upon the eyes of sexual indulgence and to practices which imply that seed comes from liquid in the region of the eyes." This may be explained by the belief of the Pythagoreans that "semen is a drop of the brain [τὸ δε σπέρμα εἶναι σταγόνα ἐγκέφαλου]." Greek Stoic philosophy conceived of the Logos spermatikos ("seminal word") as the principle of active reason that fecundated passive matter. The Jewish philosopher Philo similarly spoke in sexual terms of the Logos as the masculine principle of reason that sowed seeds of virtue in the feminine soul. The Christian Platonist Clement of Alexandria likened the Logos to physical blood as the "substance of the soul", and noted that some held "that the animal semen is substantially foam of its blood". Clement reflected an early Christian view that "the seed ought not be wasted nor scattered thoughtlessly nor sown in a way it cannot grow." Women were believed to have their own version, which was stored in the womb and released during climax. Retention was believed to cause female hysteria.
Sources: en.wikipedia.org
== Sultanate and Kingdom of Egypt == The Order was established in 1915 by Sultan Hussein Kamel of Egypt for award to persons who had rendered useful service to the country. It ranked beneath the Order of Ismail and was frequently awarded to British officers and officials serving in Egypt, as well as distinguished Egyptian citizens.The order comprised five classes:
Epididymis evolution from reptiles to mammals Epididymal hypertension – Condition that arises during human sexual arousal when seminal fluid is not ejaculatedPages displaying short descriptions of redirect targets List of distinct cell types in the adult human body
An alpha helix (or α-helix) is a sequence of amino acids in a protein that are twisted into a coil (a helix). The alpha helix is the most common structural arrangement in the secondary structure of proteins. It is also the most extreme type of local structure, and it is the local structure that is most easily predicted from a sequence of amino acids. The alpha helix has a right-handed helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O group of the amino acid that is four residues earlier in the protein sequence.
The band performed three more shows, supporting Kiss on their reunion tour, with Staley's final live performance on July 3, 1996, in Kansas City, Missouri. Aside from recording two more songs with Alice in Chains – "Get Born Again" and "Died" – and a cover of Pink Floyd's "Another Brick in the Wall" with Class of '99 during 1998, Staley was out of the public spotlight by the late 1990s. Staley struggled with drug addiction and depression for much of his adult life; he later died from a speedball overdose on April 5, 2002, at the age of 34. He was ranked at No. 27 on Hit Parader's list of "Heavy Metal's All-Time Top 100 Vocalists" in 2006, and at No. 42 on Complex magazine's list of "The 50 Best Lead Singers of All Time" in 2012. Seattle officially declared August 22, 2019, as "Layne Staley Day". Staley earned six Grammy Award nominations as a member of Alice in Chains.
Freeze branding has benefits over hot-iron branding. These include the absence of scar formation, as cryogenic temperatures do not permanently destroy all layers of an animal's skin. For similar reasons, it is also thought to be less painful than a hot-iron brand. This fact is of more than humanitarian concern: if an animal spasms in pain when the branding iron is applied this can easily dislodge the iron and produce a misbrand, doubling the mark or rendering it illegible. In practice, it is nearly impossible to place an iron in the same place once it has been accidentally moved and this fact coupled with the lower discomfort of freeze branding has contributed to the technique's wide adoption. See also Freeze brand § Controversy, below. Additionally, a freeze brand on a pigmented animal offers very high contrast year-round and increased legibility from a distance, an important time-saver in range work. Freeze brands are visible no matter the time of year because the coat that grows over them, however wooly or thick it becomes, remains white. Because it is generally the white hair that forms the final brand there is also less blotching and distortion after the animal heals compared with the scarring left by hot branding. However, freeze branding does have drawbacks. Hot branding typically involves contact between the hot iron and the animal's flesh for less than five seconds. This is termed "dwell time". Freeze branding requires longer periods of contact of up to one minute to create successful brands.
Sources: en.wikipedia.org
== Epidemiology == PMOS is the most common hormonal disorder (endocrine disorder) among women of reproductive age. When someone is infertile due to a lack of ovulation, PMOS is the most common cause. According to the World Health Organization (WHO), PMOS affects over 6 to 13% of reproductive-aged women. A 2022 review noted a prevalence between 5% and 18%. The prevalence of PMOS depends on the choice of diagnostic criteria. Using the Rotterdam criteria, around 10–13% of women have PMOS. Based on the NIH criteria, the global prevalence was 5.5%, increasing to approximately 7.1% when using the Androgen Excess Society criteria. Irrespective of the criteria, the prevalence of PMOS is increasing, likely due to an aging population, more awareness, and increasing obesity rates. Prevalence seems fairly even among people with different ethnicities, but may be higher in people from Southeast Asia and the Eastern Mediterranean. But PMOS can express differently. For instance, in African and Hispanic American people with PMOS, there is more insulin resistance compared to other ethnic groups. The same is true for South Asian people with PMOS, who also have more metabolic symptoms and higher BMIs. East Asian women typically have less hirsutism and lower BMI compared to other groups. While early small-scale studies found that transmasculine people were more likely to have PMOS than cis women, this was not found in a larger, more rigorous study.
==== Lobuloalveolar development ==== Progesterone plays an important role in breast development. In conjunction with prolactin, it mediates lobuloalveolar maturation of the mammary glands during pregnancy to allow for milk production, and thus lactation and breastfeeding of offspring following parturition (childbirth). Estrogen induces expression of the progesterone receptors (PR) in breast tissue, and hence progesterone is dependent on estrogen to mediate lobuloalveolar development. It has been found that RANKL is a critical downstream mediator of progesterone-induced lobuloalveolar maturation. RANKL knockout mice show an almost identical mammary phenotype to PR knockout mice, including normal mammary ductal development, but complete failure of the development of lobuloalveolar structures.
=== CPM, thiol-specific dyes === Alexandrov et al. (2008) published a variation on the Thermofluor assay where SYPRO Orange was replaced by N-[4-(7-diethylamino-4-methyl-3-coumarinyl)phenyl]maleimide (CPM), a compound that only fluoresces after reacting with a nucleophile. CPM has a high preference for thiols over other typical biological nucleophiles and therefore will react with cysteine side chains before others. Cysteines are typically buried in the interior of a folded protein as they are hydrophobic. When a protein denatures cysteine thiols become available and a fluorescent signal can be read from reacted CPM. The excitation and emission wavelengths for reacted CPM are 387 nm/ 463 nm so a fluorescence plate reader or a qPCR machine with specialized filters is required. Alexandrov et al. used the technique successfully on the membrane proteins Apelin GPCR and FAAH as well as β-lactoglobin which fibrillates on heating rather than going to a molten globule.
Pst DC3000 has been modified to create the mutant strain Pst DC3000∆avrPto∆avrPtoB (Pst DC3000∆∆), which expresses neither AvrPto nor AvrPtoB. By infecting RG-PtoR with Pst DC3000∆∆, ETI to the pathogen is not triggered due to the absence of the main effectors recognized by the Pto/Prf complex. In the lab this is highly valuable, as using Pst DC3000∆∆ allows researchers to study the function of PTI-candidate genes in RG-PtoR, which would otherwise be masked by ETI. Another useful DC3000 derivative is Pst DC3000∆avrPto∆avrPtoB∆fliC (Pst DC3000∆∆∆). Like Pst DC3000∆∆, this strain does not express AvrPto and AvrPtoB, but it also has an additional knock-out for fliC, the gene encoding flagellin, whose fragments serve as main PAMPs required for tomato PTI. By comparing plants within the same line that have been infected with either Pst DC3000∆∆ or Pst DC3000∆∆∆, researchers can determine if genes of interest are important to the flagellin recognition pathway of PTI. By treating CRISPR-induced tomato knockout mutants (in a RG-PtoR background) with Pst DC3000, Pst DC3000∆avrPto∆avrPtoB, or Pst DC3000∆avrPto∆avrPtoB∆fliC has led to the characterization of key components of the tomato immune system and continues to be used to further the field of tomato pathology.
Meprobamate, 2-methyl-2-propyl-1,3-propanediol dicarbamate is synthesized by the reaction of 2-methylvaleraldehyde with two molecules of formaldehyde and the subsequent transformation of the resulting 2-methyl-2-propylpropan-1,3-diol into the dicarbamate via successive reactions with phosgene and ammonia.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
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.