If you have been reading about intranasal delivery and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-10-22. Numbers and descriptions here follow the published literature rather than marketing material.
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。
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
| 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 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.
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.
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.
Emoxypine inhibits oxidation of biomembrane lipids. Increases the activity of antioxidant enzymes, specifically that of superoxide dismutase, responsible for the formation and consumption of lipid peroxides and active oxygen forms. Inhibits free radicals during the synthesis of prostaglandin catalyzed cyclooxygenase and lipoxygenase, increases the correlation prostacyclin/ thromboxane A2 and blocks the leukotriene formation. Increases the content of polar fraction of lipids (phosphatidyl serine and phosphatidyl inositol) and reduces the cholesterol/phospholipids ratio which proves its lipid-regulatory properties; shifts structure transition into the low temperature zones, that is provokes the reduction of membrane viscosity and the increase of its fluidity, increases lipid-protein ratio. Modulates the activity of membrane-bound enzymes: phosphodiesterase, cyclic nucleotides, adenylate cyclase, aldoreductase, acetylcholinesterase. Modulates the receptor complexes of the brain membranes, i.e. benzodiazepine, GABA, acetylcholine receptors by increasing their binding ability. Stabilizes biomembranes, i.e. membrane structures of blood cells - erythrocytes and thrombocytes during their haemolysis or mechanical injury accompanied by the formation of free radicals. Changes the monoamine level and increases the dopamine content in the brain. Still, the antioxidant and membrane-protective effects have not been proven in reviews and meta-analyses.
Metreleptin, sold under the brand name Myalept among others, is a synthetic analog of the hormone leptin used to treat various forms of dyslipidemia. It has been approved in Japan for metabolic disorders including lipodystrophy and in the United States as replacement therapy to treat the complications of leptin deficiency, in addition to diet, in patients with congenital generalized or acquired generalized lipodystrophy. The most common side effects include hypoglycemia and weight loss. It was approved for medical use in Canada in January 2024.
The entactogen MDMA is a serotonin releasing agent and, while it also possesses other actions such as concomitant release of norepinephrine and dopamine and weak direct agonism of the serotonin 5-HT2 receptors, its serotonin release plays a key role in its unique entactogenic effects. Entactogens like MDMA should be distinguished from other drugs such as stimulants like amphetamine and psychedelics like LSD, although MDMA itself also has some characteristics of both of these types of agents. Coadministration of selective serotonin reuptake inhibitors (SSRIs), which block the serotonin transporter (SERT) and prevent MDMA from inducing serotonin release, markedly reduce the subjective effects of MDMA, demonstrating the key role of serotonin in the effects of the drug. Serotonin releasing agents like MDMA achieve much greater increases in serotonin levels than SSRIs and have far more robust of subjective effects. Besides MDMA, many other entactogens also exist and are known.
Sources: en.wikipedia.org
Particle size after micronization is most commonly measured by laser diffraction under USP general chapter <429> and the harmonized ISO 13320 standard, and reported as the volume-weighted D10, D50 and D90 statistics. High-energy mechanical micronization can introduce surface amorphization, polymorphic conversion and triboelectric charging, all of which affect downstream stability and processability and often require post-milling conditioning to control.
==== Insulinomas ==== A primary B-cell tumor, such as an insulinoma, is associated with hypoglycemia. This is a tumor located in the pancreas. An insulinoma produces insulin, which in turn decreases glucose levels, causing hypoglycemia. Normal regulatory mechanisms are not in place, which prevent insulin levels from falling during states of low blood glucose. During an episode of hypoglycemia, plasma insulin, C-peptide, and proinsulin will be inappropriately high.
=== Neuroprotection and DNA repair === Estrogen regulated DNA repair mechanisms in the brain have neuroprotective effects. Estrogen regulates the transcription of DNA base excision repair genes as well as the translocation of the base excision repair enzymes between different subcellular compartments. Estrogen provides neuroprotection by modulating the endocannabinoid system activity, primarily through the regulation of fatty acid amide hydrolase (FAAH) enzyme expression and the endocannabinoid receptor Cβ1 levels. The protective effects appears to work through a fine-tuning mechanism where by estrogen both suppresses excessive endocannabinoid signaling at the Cβ1receptor (which can be neurotoxic under stress) while simultaneously maintaining physiological endocannabinoid tine needed for normal neural function.
Sources: en.wikipedia.org
By the late 1940s, the economic wounds from years of redlining and restrictive covenants hurt the standard of living for many African Americans and minorities living in Detroit. With limited housing opportunities and sky-high rents, those living in "red" neighborhoods like Black Bottom and Paradise Valley often had little financial ability to pay for private apartments or housing repairs. Consequences of close-quarter living were exacerbated by an influx of black immigrants during the Great Migration and World War II. The decaying neighborhoods also developed sanitation problems; garbage pickups were rare, and trash littered the street, accelerating the spread of diseases and enticing pests. Perceptions of "urban blight" and a need for "slum clearance" in these areas were fueled especially by (majority white) Detroit city planners, who classified over two-thirds of housing in Paradise Valley as substandard. Detroit Mayor Edward Jeffries put forth a plan for "urban renewal" in Black Bottom and Paradise Valley neighborhoods in 1944. Utilizing eminent domain laws, the government began taking down buildings in the Black Bottom neighborhood in 1949. Local government officials popularized the push for urban renewal in post-World War II Detroit in conjunction with real estate agents and bank owners, who stood to gain from investment in new buildings and wealthier residents.
==== Gangrene and gallbladder rupture ==== Cholecystitis causes the gallbladder to become distended and firm. Distension can lead to decreased blood flow to the gallbladder, causing tissue death and eventually gangrene. Once tissue has died, the gallbladder is at greatly increased risk of rupture (perforation), which can cause sharp pain. Rupture can also occur in cases of chronic cholecystitis. Rupture is a rare but serious complication that leads to abscess formation or peritonitis. Massive rupture of the gallbladder has a mortality rate of 30%.
== A == ADI – Ambient desorption ionization AE – Appearance energy AFADESI – Air flow-assisted desorption electrospray ionization AFAI – Air flow-assisted ionization AFAPA – Aerosol flowing atmospheric-pressure afterglow AGHIS – All-glass heated inlet system AIRLAB – Ambient infrared laser ablation AMS – Accelerator mass spectrometry AMS – Aerosol mass spectrometer AMU – Atomic mass unit AP – Appearance potential AP MALDI – Atmospheric pressure matrix-assisted laser desorption/ionization APCI – Atmospheric pressure chemical ionization API – Atmospheric pressure ionization APPI – Atmospheric pressure photoionization ASAP – Atmospheric Sample Analysis Probe ASMS – American Society for Mass Spectrometry
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 consists mainly of animal experiments and small clinical reports, with much of the clinical material published in Russian-language journals. Large independent trials are scarce. Separating reliable effects from chance findings is consequently difficult.