A practical reference on ACTH fragment: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-05-28 and is reviewed periodically as new material appears.
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.
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.
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
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.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
IL-10 shares similar immunomodulating mechanisms to TGF-β. It is thought that both cytokines reduce the rate of apoptosis in human alveolar macrophages, thus indirectly enhancing alveolar macrophage-mediated inhibition of T-cell proliferation. There is a significant increase in the basal rate of apoptosis upon activation by bacterial products. Apoptosis is particularly regulated by the presence of cytokines: IFNγ increases the rate of apoptosis, whereas IL-10 and TGF-β decrease it. However, IL-10 has counterproductive effects on the immune system, and has been shown to actually promote infection by foreign pathogens. The role of IL-10 in bacterial and parasitic infection has been discovered as a strategy to evade host immune systems. There are bacteria which parasitize AMs by invading through their membranes, and thrive by growing and replicating inside of them, exploiting AMs as host cells. Normally, this infection can be eliminated by T-cells, which activate enzymes in alveolar macrophages that destroy the bacteria; but these bacteria have been shown to alter the cytokine signaling network to their advantage. As an inhibitory cytokine, IL-10 facilitates the infection of human alveolar macrophages and monocytes by completely reversing the protective effect of IFNγ against intracellular Legionella pneumophila replication.
== Types of assays == All enzyme assays measure either the consumption of substrate or production of product over time. A large number of different methods of measuring the concentrations of substrates and products exist and many enzymes can be assayed in several different ways. Biochemists usually study enzyme-catalysed reactions using four types of experiments:
== See also == Aptamer – Oligonucleotide or peptide molecules that bind specific targets Deoxyribozyme – DNA oligonucleotides that can perform a specific chemical reaction Anti-thrombin aptamers – Oligonucleotides which recognize the exosites of human thrombin Bacterial one-hybrid system – Method for identifying the sequence-specific target site of a DNA-binding domain SMiLE-Seq – Similar method using a microfluidic device loaded with “bait” transcription factors and DNA molecules
=== Housing === Moore has described himself as a "YIMBY". He supports the right to counsel in eviction cases, saying that providing tenants with access to counsel is "the just thing to do and it is the right thing to do". On his campaign website, Moore says he would address the "unfair appraisal values in historically redlined neighborhoods" and provide increased funding for the Maryland Department of Housing and Community Development. During a town hall in August 2023, Moore suggested that nonprofits could be used to help lower housing costs in addition to increasing the state's affordable housing inventory and supporting current homeowners. In January 2024, Moore introduced bills to increase federal funding and reducing barriers for affordable housing projects in the state, especially those around commuter rail stations, as well as legislation establishing a "Tenant's Bill of Rights" and providing additional protections to renters against evictions. While Moore's tenant protections bills passed the legislature unchanged, legislators opted to weaken the Housing Expansion and Affordability Act by removing provisions that would block jurisdictions from using an adequate public facilities ordinance to block the construction of affordable housing and modifying the qualifications needed for affordable housing projects to be eligible for density bonuses. In October 2024, Moore signed an executive order aimed at removing 5,000 of Baltimore's 13,000 vacant homes within five years.
Sources: en.wikipedia.org
In June 2012, IKEA announced it had applied for permission to invest $1.9 billion in India and set up 25 retail stores. An analyst from Fitch Group stated that the 30 percent requirement was likely to significantly delay if not prevent most single brand majors from Europe, USA and Japan from opening stores and creating associated jobs in India. On 14 September 2012, the government of India announced the opening of FDI in multi-brand retail, subject to approvals by individual states. On 20 September 2012, the Government of India formally notified the FDI reforms for single and multi brand retail, thereby making it effective under Indian law.
=== Southeast Asia === The Javanese society of Mataram had gained knowledge of making bean curd (in Old Javanese: tahu) by the time said item was listed among foods served in a ceremonial feast for Balitung off an inscription dated 902 CE, but long after soy beans (kaḍle) were introduced to Javan cultivation by South Indian traders based on morphological comparisons to Indian soy varieties and linguistic evidence.
=== Horizontal plate filters === Horizontal plate filter paper is commonly utilized in industrial processing. Filter paper typically is designed to fit the manufacturers specifications. Absolute micron retention can range from 1–100 microns but Diatomaceous earth is commonly used with filter paper to obtain sub-micron filtration. Activated carbon or other filter aids can be used with the filter paper to form a filter cake to achieve specific results. Filter paper can be impregnated with DE or activated carbon.
The development of secondary sex characteristics in women is driven by estrogens, to be specific, estradiol. These changes are initiated at the time of puberty, most are enhanced during the reproductive years, and become less pronounced with declining estradiol support after menopause. Thus, estradiol produces breast development, and is responsible for changes in the body shape, affecting bones, joints, and fat deposition. In females, estradiol induces breast development, widening of the hips, a feminine fat distribution (with fat deposited particularly in the breasts, hips, thighs, and buttocks), and maturation of the vagina and vulva, whereas it mediates the pubertal growth spurt (indirectly via increased growth hormone secretion) and epiphyseal closure (thereby limiting final height) in both sexes.
There are drawbacks to each strategy, namely that fluorescent reporters do not allow for enrichment for proteomic analysis, while biotin-based affinity tags co-purify with endogenously biotinylated proteins. A linker group is used to connect the reactive group to the reporter, ideally in a manner that does not alter the activity of probe. The most common linker groups are long alkyl chains, derivatized PEGs, and modified polypeptides. Under the assumption that enzymes vary in their structure, function, and associations depending on a system's physiological or developmental state, it can be inferred that the accessibility of an enzyme's active site will also vary. Therefore, the ability of an ABPP probe to label an enzyme will also vary across conditions. Thus, the binding of a probe can reveal information around an enzyme's functional characteristics in different contexts. High-throughput screening has benefitted from ABPP, particularly in the area of competitive inhibition assays, in which biological samples are pre-incubated with drug candidates, then made to compete with ABPP probes for binding to target enzymes. Compounds with high affinity to their targets will prevent binding of the probe, and the degree of probe binding can be used as an indication of compound affinity. Because ABPP probes label classes of enzymes, this approach can also be used to profile drug selectivity, as highly selective compounds will ideally outcompete probes at only a small number of proteins.
Sources: en.wikipedia.org
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.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。