A practical reference on ACTH analog: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-12-20. Anything still debated is marked as such rather than presented as settled.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
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.
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 |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
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。
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 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.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
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.
fractionation A separation process in which a particular quantity of a mixture is divided during a phase transition into a number of smaller quantities, known as fractions, for which the chemical composition varies according to a gradient. Fractionation exploits subtle differences in some specific property (e.g. mass, boiling point, solubility, etc.) between the mixture's component compounds, making it possible to isolate more than two components of a mixture at the same time. There are many varieties of fractionation employed in many branches of science and technology.
These studies provide a new view of the kinetics and dynamics of single enzymes, as opposed to traditional enzyme kinetics, which observes the average behaviour of populations of millions of enzyme molecules. An example progress curve for an enzyme assay is shown above. The enzyme produces product at an initial rate that is approximately linear for a short period after the start of the reaction. As the reaction proceeds and substrate is consumed, the rate continuously slows (so long as the substrate is not still at saturating levels). To measure the initial (and maximal) rate, enzyme assays are typically carried out while the reaction has progressed only a few percent towards total completion. The length of the initial rate period depends on the assay conditions and can range from milliseconds to hours. However, equipment for rapidly mixing liquids allows fast kinetic measurements at initial rates of less than one second. These very rapid assays are essential for measuring pre-steady-state kinetics. Most enzyme kinetics studies concentrate on this initial, approximately linear part of enzyme reactions. However, it is also possible to measure the complete reaction curve and fit this data to a non-linear rate equation. This way of measuring enzyme reactions is called progress-curve analysis. This approach is useful as an alternative to rapid kinetics when the initial rate is too fast to measure accurately.
In fact neon is the most electronegative element, but the Pauling scale cannot measure its electronegativity because it does not form covalent bonds with most elements. An element's electronegativity varies with the identity and number of the atoms it is bonded to, as well as how many electrons it has already lost: an atom becomes more electronegative when it has lost more electrons. This sometimes makes a large difference: lead in the +2 oxidation state has electronegativity 1.87 on the Pauling scale, while lead in the +4 oxidation state has electronegativity 2.33.
Mummies from Oceania are not limited only to Australia. Discoveries of mummified remains have also been located in New Guinea, New Zealand, and the Torres Strait, though these mummies have been historically harder to examine and classify. Prior to the 20th century, most literature on mummification in the region was either silent or anecdotal. However, the boom of interest generated by the scientific study of Egyptian mummification lead to more concentrated study of mummies in other cultures, including those of Oceania.
In August 2025, Newsom secured legislative approval of California Proposition 50, a state constitutional amendment to allow congressional redistricting. The goal was to switch seats from Republican to Democratic control in response to the 2025 Texas gerrymander that would add five new Republican seats. Voters approved the measure in November.
Sources: en.wikipedia.org
Most newspapers in Hong Kong are written in Chinese. There are also English-language newspapers, the major one being the South China Morning Post, with The Standard serving as a business-oriented alternative. A variety of Chinese-language newspapers are published daily; the most prominent are Ming Pao and Oriental Daily News. Local publications are often partisan, with pro-Beijing or pro-democracy sympathies. The central government has a print-media presence in the territory through the state-owned Ta Kung Pao and Wen Wei Po. Several international publications have regional operations in Hong Kong, including The Wall Street Journal, the Financial Times, USA Today, TimeOut, The Nikkei and Vogue Hong Kong. Four free-to-air television broadcasters operate in the territory; TVB, HKTVE, HOY and Phoenix Television air eight digital channels. TVB, Hong Kong's dominant television network, has an 80% viewer share. Paid television services operated by PCCW offer hundreds of additional channels and cater to a variety of audiences. RTHK is the public broadcaster, providing seven radio channels and six free-to-air television channels. Ten non-domestic broadcasters air programming for the territory's foreign population. Access to media and information over the Internet is not subject to mainland Chinese regulations, including the Great Firewall, but local internet censorship applies.
==== Economic Plan ==== During Bukele's second inauguration, he stated that his second term would focus on improving the Salvadoran economy with "bitter medicine" ("medicina amarga"). In July 2024, Bukele threatened to mass-arrest vendors, importers, and distributors who engaged in price gouging. Later that month, he announced the beginning of a six-phase Economic Plan ("Plan Económico"). Phase one, known as "Feeding" ("Alimentación"), involved the establishment of 30 food distribution centers and the removal of tariffs on certain agricultural imports for ten years. Phase two, known as "Technology" ("Tecnología"), involved the construction of data centers and technological parks in El Salvador. Bukele stated that his Economic Plan would create 4,000 jobs. Phase three, known as "Logistics" ("Logística"), involved the investment of US$1.6 billion into modernizing the ports of Acajutla and La Unión and the Turkish company Yılport Holdings operating the ports for 50 years.
state of the 2028 presidential primaries cycle for the Democratic Party in the upcoming presidential election. August 17 Trump orders the Pentagon to reduce yearly joint exercises with South Korea, saying that the ally refused to help with the 2026 Iran war and citing his good relationship with North Korean leader Kim Jong Un. The 60-day deadline for the US and Iran to negotiate a "final deal" to end the 2026 Iran war expires. Following the official end of the US-Iran ceasefire, Trump urges Iran to surrender. Trump states that the Iranian regime will not agree to the deal that the US feels is needed, and he is not looking to extend the Memorandum of Understanding. Opening statements begin in the murder trial of Duane "Keffe D" Davis, who is accused of orchestrating the 1996 drive-by shooting that killed rapper Tupac Shakur in Las Vegas. August 18 The Defense Department orders an audit of 30 universities' partnerships with foreign institutions, most of which are Chinese, but also include Russian and Iranian institutions. President Tomoko Akane of the International Criminal Court and a senior trial lawyer at the court who was part of a team which sought an arrest warrant for Israeli Prime Minister Benjamin Netanyahu for alleged war crimes in the Gaza war is sanctioned by the US. Newly revealed emails show that a silent channel between ICE and the Iranian government shaped deportation flights in 2025 and 2026 despite tensions mounting between the two states. The national debt surpasses $40 trillion for the first time.
In 80–85% of cases, the ALK detected in ALK-positive ALCL is a NPM1-ALK fusion protein. It is made by a fusion of NPM1 gene, which makes nucleophosmin 1, located on the long or "q" arm of chromosome 5 at position 35 (notated as 5q35) with the ALK gene located on the short or "p" arm of chromosome 2 at position 23 (notated as 2p23) to form a chimeric gene notated as (2;5)(p23;q35). In 13% of cases ALK fuses with the TPM3 gene or in <1% of cases for each of the following genes: TFG, ATIC, CLTC, TPM4, MSN, RNF213 (also termed ALO17), MYH9, or TRAF1. All of these fusion proteins are considered to act like NPMI-ALK in possessing high ALK activity that promotes the development and progression ALK-positive ALCL by activating the cell signaling pathways cited in the Introduction. 15% Of individuals with ALK-positive ALCL also have point mutations in the NOTCH1 gene. While most of these abnormalities are thought to be detrimental not all are. For example, DUSP22 gene rearrangements are associated with favorable outcomes in ALK-positive (as well as ALK-negative) ALCL.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
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.