A practical reference on heptapeptide: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-03-14 and is reviewed periodically as new material appears.
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。
各国监管态度分化明显。俄罗斯按处方药管理,部分东欧国家留有使用记录;欧盟与美国未批准其作为药物上市,市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录,跨境携带则受目的地药品法规约束。
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
| Property | Value | Notes |
|---|---|---|
| 结构类别 | 线性合成七肽 | 无环化结构,不含二硫键 |
| 氨基酸序列 | Met-Glu-His-Phe-Pro-Gly-Pro | N 端为甲硫氨酸 |
| 分子量 | 约 814 Da | 游离碱形式的计算值 |
| 外观 | 白色至类白色粉末 | 具吸湿性 |
| 溶解性 | 易溶于水 | 亦可溶于甲醇等极性溶剂 |
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.
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.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
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.
== Career == Using the profits from his construction business on Long Island, Kimmel and his friend, Milton Cooper, moved to Florida and founded the Kimco Realty Corporation in 1958. Kimco derives its name from the surnames of the two founders. They correctly presaged that Florida was in the midst of transitioning from a vacation destination to a retirement haven. Their first investment was a small strip mall with two stores attached to a Zayre's. Sticking to the same formula - focusing on strip developments in new subdivisions (often following utility trucks out to find new developments - they were wildly successful and over the next thirty years, Kimco's portfolio grew to over 1,900 properties of which 1,100 were strip shopping centers. Their business expanded internationally and included properties in Canada, Mexico, Chile and Brazil. The company went public in 1991 raising $128 million becoming the first Real Estate Investment Trust (REIT) IPO in history. Kimmel retired in 1991 to focus on philanthropic activities.
Traditionally used packaging films like LDPE (low-density polyethylene), PVC (polyvinyl chloride), EVA (ethylene-vinyl acetate) and OPP (oriented polypropylene) are not permeable enough for highly respiring products like fresh-cut produce, mushrooms and broccoli. As fruits and vegetables are respiring products, there is a need to transmit gases through the film. Films designed with these properties are called permeable films. Other films, called barrier films, are designed to prevent the exchange of gases and are mainly used with non-respiring products like meat and fish. MAP films developed to control the humidity level as well as the gas composition in the sealed package are beneficial for the prolonged storage of fresh fruits, vegetables and herbs that are sensitive to moisture. These films are commonly referred to as modified atmosphere/modified humidity packaging (MA/MH) films.
The term "computer virus" may be used as an overarching phrase to include all types of true viruses, malware, including computer worms, Trojan horses, most rootkits, spyware, dishonest adware and other malicious and unwanted software (though all are technically unique), and proves to be quite financially lucrative for criminal organizations, offering greater opportunities for fraud and extortion whilst increasing security, secrecy and anonymity. Worms may be utilized by organized crime groups to exploit security vulnerabilities (duplicating itself automatically across other computers a given network), while a Trojan horse is a program that appears harmless but hides malicious functions (such as retrieval of stored confidential data, corruption of information, or interception of transmissions). Worms and Trojan horses, like viruses, may harm a computer system's data or performance. Applying the Internet model of organized crime, the proliferation of computer viruses and other malicious software promotes a sense of detachment between the perpetrator (whether that be the criminal organization or another individual) and the victim; this may help to explain vast increases in cyber-crime such as these for the purpose of ideological crime or terrorism. In mid July 2010, security experts discovered a malicious software program that had infiltrated factory computers and had spread to plants around the world. It is considered "the first attack on critical industrial infrastructure that sits at the foundation of modern economies," notes the New York Times.
Sources: en.wikipedia.org
Lewis, Daniel. The Feathery Tribe: Robert Ridgway and the Modern Study of Birds. Yale University Press. [1]. Ornithologie (1773–1792) Francois Nicholas Martinet Digital Edition Smithsonian Digital Libraries "West Midland Bird Club: Older Organisations". Archived from the original on May 9, 2013. Retrieved May 23, 2004. History of ornithology in North America History of ornithology and ornithology collections in Victoria, Australia on Culture Victoria History of ornithology in China Hill ornithology collections Newton, Alfred; Mitchell, Peter Chalmers (1911). "Ornithology" . Encyclopædia Britannica. Vol. 20 (11th ed.). pp. 299–326.
=== Effects of the WldS mutation === The mutation causes no harm to the mouse. The only known effect is that the Wallerian degeneration is delayed by up to three weeks on average after injury of a nerve. At first, it was suspected that the Wlds mutation slows down the macrophage infiltration, but recent studies suggest that the mutation protects axons rather than slowing down the macrophages. The process by which the axonal protection is achieved is poorly understood. However, studies suggest that the Wlds mutation leads to increased NMNAT1 activity, which leads to increased NAD+ synthesis. This in turn activates SIRT1-dependent process within the nucleus, causing changes in gene transcription. NAD+ by itself may provide added axonal protection by increasing the axon's energy resources. More recent work, however, raises doubt that either NMNAT1 or NAD+ can substitute for the full length Wlds gene. These authors demonstrated by both in vitro and in vivo methods that the protective effect of overexpression of NMNAT1 or the addition of NAD+ did not protect axons from degeneration. However, later studies showed that NMNAT1 is protective when combined with an axonal targeting peptide, suggesting that the key to the protection provided by WldS was the combination of NMNAT1's activity and the axonal localization provided by the N-terminal domain of the chimeric protein. The provided axonal protection delays the onset of Wallerian degeneration. Schwann cell activation should therefore be delayed, as they would not detect axonal degradation signals from ErbB2 receptors.
Compared with non-parents, parents with children have lower levels of well-being and life satisfaction until children move out of the household, at which point parents have higher well-being and satisfaction. In addition, parents report more feelings of depression and anxiety than non-parents. However, when adults without children are compared to empty nest parents, parenthood is positively associated with emotional well-being. People found parenthood to be more stressful in the 1970s than they did in the 1950s. This is thought to be because of social changes in regards to employment and marital status. Males apparently become less happy after the birth of a child due to added economic pressure and taking on the role of being a parent. A conflict between partners can arise when the couple does not desire traditional roles, or has an increasing number of roles. Unequal responsibilities of child-rearing between men and women account for this difference in satisfaction. Fathers who worked and shared an equal part in child-raising responsibilities were found to be the least satisfied. Research shows that single parents have higher levels of distress and report more mental health problems than married persons. Researchers implemented the Huta & Ryan Scale: Four Eudaimonic Measurement Questionnaire to analyze the participants eudaimonic motives, through motivation towards activities. The investigation was conducted on Canadian university undergraduates. The four eudaimonic pursuits as described by Huta & Ryan are:
Sources: en.wikipedia.org
不存在。它是依据 ACTH 的一段序列人工设计的分子,天然蛋白质中找不到与之完全相同的七肽。名称属于研究代号,而非天然物质名。
Semax 对应 ACTH 第 4 至第 10 位的片段,并在两端做了替换与延长,使其不再具备促肾上腺皮质激素的典型内分泌活性。这一改动同时改变了它在体内的稳定性与分布特征。
俄罗斯将其列为处方药物,需要医生开具处方。多数其他国家把它当作研究化合物,不能作为药品销售或宣称疗效。具体合法性取决于当地法规。
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.