Everything below concerns melanocortin signalling. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-01-15. Numbers and descriptions here follow the published literature rather than marketing material.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity specification | ≥ 95 % of peak area by HPLC | Some suppliers quote 98 % or higher |
| Identity confirmation | Mass spectrometry (electrospray or MALDI) | Observed mass is compared with the calculated mass |
| Common analytical method | Reversed-phase HPLC on a C18 column | Acetonitrile and water gradients with trifluoroacetic acid |
| Primary degradation route | Oxidation of the methionine residue | Yields a sulfoxide that separates cleanly on chromatography |
| Storage of dissolved material | Aliquoted and frozen at −20 °C or below | Single-use aliquots avoid repeated temperature cycling |
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。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
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.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
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.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
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.
== Pharmacology == The pharmacology of 5α-reductase inhibition is complex, but involves the binding of NADPH to the enzyme followed by the substrate. Specific substrates include testosterone, progesterone, androstenedione, epitestosterone, cortisol, aldosterone, and deoxycorticosterone. The entire physiologic effect of their reduction is unknown, but likely related to their excretion or is itself physiologic. 5α-Reductase reduces the steroid Δ4,5 double bond in testosterone to its more active form DHT. Thus, inhibition results in decreased amounts of DHT. Because of this, slight elevations in testosterone and estradiol levels occur. The 5α-reductase reaction is a rate-limiting step in the testosterone reduction and involves the binding of NADPH to the enzyme followed by the substrate.
Isocitrate dehydrogenase 1 (NADP+), soluble is an enzyme that in humans is encoded by the IDH1 gene on chromosome 2. Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses, one of which uses NAD+ as the electron acceptor and the other NADP+. Five isocitrate dehydrogenases have been reported: three NAD+-dependent isocitrate dehydrogenases, which localize to the mitochondrial matrix, and two NADP+-dependent isocitrate dehydrogenases, one of which is mitochondrial and the other predominantly cytosolic. Each NADP+-dependent isozyme is a homodimer. The protein encoded by this gene is the NADP+-dependent isocitrate dehydrogenase found in the cytoplasm and peroxisomes. It contains the PTS-1 peroxisomal targeting signal sequence. The presence of this enzyme in peroxisomes suggests roles in the regeneration of NADPH for intraperoxisomal reductions, such as the conversion of 2,4-dienoyl-CoAs to 3-enoyl-CoAs, as well as in peroxisomal reactions that consume 2-oxoglutarate, namely the alpha-hydroxylation of phytanic acid. The cytoplasmic enzyme serves a significant role in cytoplasmic NADPH production. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Sep 2013]
He was succeeded by Robin Dutt, who himself left the club for Bayer Leverkusen in 2011. On 10 May 2009, Freiburg secured promotion into the Bundesliga once again, beating TuS Koblenz in an away game 5–2.
Sources: en.wikipedia.org
The relationships between India in the days of the British Raj and the United States were thick. Swami Vivekananda promoted Yoga and Vedanta in the United States at the World's Parliament of Religions in Chicago, during the World's Fair in 1893. Mark Twain visited India in 1896 and described it in his travelogue Following the Equator with both revulsion and attraction before concluding that India was the only foreign land he dreamed about or longed to see again. Regarding India, Americans learned more from English writer Rudyard Kipling. Mahatma Gandhi had an important influence on the philosophy of non-violence promoted by American civil rights movement leader Martin Luther King Jr. in the 1950s. Former American Military Officer and later a prominent figure in the spiritual and philosophical movement of Theosophy Henry Steel Olcott, left New York in December 1878 to relocate the headquarters of the Theosophical Society to India. He and the society arrived in Bombay on February 16, 1879. Olcott's objective was to immerse himself in the culture of India, the birthplace of his spiritual inspiration, the Buddha. The Society's headquarters were established at Adyar, Chennai, where Olcott also founded the Adyar Library and Research Centre. He aimed to obtain authentic translations of sacred texts from Buddhist, Hindu, and Zoroastrian religions to provide Westerners with a true understanding of Eastern philosophies, countering Westernized interpretations. Throughout his time in India, Olcott worked tirelessly to bridge the cultural and spiritual gap between East and West.
=== Formation === There are several hypotheses proposed regarding the formation of Tarlov cysts, including: hemorrhagic infiltration of spinal tissue, inflammation within the nerve root cysts followed by inoculation of fluids, developmental or congenital origin, arachnoidal proliferation along and around the exiting sacral nerve root, and breakage of venous drainage in the perineuria and epineurium secondary to hemosiderin deposition after trauma. Tarlov himself theorized that the perineural cysts form as a result of blockage of venous drainage in the perineurium and epineurium secondary to hemosiderin deposition, after local trauma. Another theory gaining increasing popularity, over the past decade, is one postulated by Fortuna et al.; it described perineural cysts to be the results of congenital arachnoidal proliferation along the exiting sacral nerve roots. Some research on the migration of inflammatory cell into spinal has been studied. Additionally, in vivo and in vitro studies show inflammation induced by CNS injury causes distinct cystic cavitations created by astrocyte migration.
=== Preclinical === 2-Bromo-LSD (bromolysergide; BOL-148; BETR-001, TD-0148A) – non-hallucinogenic serotonin 5-HT2A receptor agonist and other actions – cluster headache GA-2601 – undefined mechanism of action – migraine [32] MST-02 – undefined mechanism of action – migraine [33] TACT908 – serotonin 5-HT1B receptor agonist and non-hallucinogenic serotonin 5-HT2A receptor partial agonist – cluster headache
==== By ions ==== Upon illumination of the chloroplasts, the pH of the stroma rises from 7.0 to 8.0 because of the proton (hydrogen ion, H+) gradient created across the thylakoid membrane. The movement of protons into thylakoids is driven by light and is fundamental to ATP synthesis in chloroplasts (Further reading: Photosynthetic reaction centre; Light-dependent reactions). To balance ion potential across the membrane, magnesium ions (Mg2+) move out of the thylakoids in response, increasing the concentration of magnesium in the stroma of the chloroplasts. RuBisCO has a high optimal pH (can be >9.0, depending on the magnesium ion concentration) and, thus, becomes "activated" by the introduction of carbon dioxide and magnesium to the active sites as described above.
Sources: en.wikipedia.org
Taxodioxylon gysaceum is an extinct species of conifer presently found as fossil wood. Samples of the same wood in various stages of degradation were collected from a forest in Italy, originally existing during the Pliocene period. These samples were milled and filtered into different fractions by coarseness before steam distillation was utilized to extract terpenes. The extraction was then analyzed through GC/MS. The comparative degree of degradation was determined by analysis of holocellulose contents in each sample. Holocellulose refers to the fraction of plant biomass that includes cellulose and hemicellulose but excludes lignin. These carbohydrates are broken down during decomposition, and so their concentrations can be used as a measure of the degree of degradation. A variety of terpenes were detected in the degraded lignite samples, including more than 10% ferruginol, between 5 and 10% podocarpodiol, and less than 5% of sugiol. These compounds were hypothesized to have become more prevalent in the degraded sample due to preferential decomposition of other compounds. The presence of these terpenes in this sample suggest that the organism belongs to the Cupressaceae, Podocarpaceae, or Taxodiaceae families. Given the specific combination of terpenes present, the sample was identified as Taxodioxylon gypsaceum. This combination of terpenes has also been detected in other samples known to be Taxodioxylon gypsaceum, further supporting this identification.
=== Lawsuit === Ferrara Candy Company came under fire in 2017 because of their Lemonheads due to the opaque packaging. A lawsuit was filed claiming that customers had been deceived into believing there was more product in the boxes than there actually were, due to the packaging. The Ferrara Candy Company settled for $2.5 million with the plaintiff and agreed to provide a cash payment for those who were impacted and to modify the quality control procedure.
==== iLet Bionic Pancreas ==== The iLet Bionic Pancreas system, developed by Beta Bionics, is an automated insulin delivery system comprising the iLet ACE Pump, the iLet Dosing Decision Software, and a compatible continuous glucose monitor — either the Dexcom G6/G7 or the FreeStyle Libre 3 Plus sensor. The system is designed to automate insulin dosing with minimal user input, relying solely on the user’s body weight for initialization. It utilizes three algorithms to manage insulin delivery: a basal insulin controller, which adjusts basal rates every five minutes based on current glucose values, glucose trends, and historical CGM data; a bolus correction controller, which incorporates insulin on board in addition to these factors to calculate correction doses; and a meal announcement controller, which determines bolus doses according to the user’s estimation of meal size. The system does not require user-programmed basal rates, insulin-to-carbohydrate ratios, or correction factors. It supports three glucose targets—110, 120, or 130 mg/dL—and is approved for use in individuals aged six years and older with type 1 diabetes.
Sources: en.wikipedia.org
Suppliers normally quote a percentage of total chromatographic peak area, most often from reversed-phase HPLC. That figure says nothing about what the remaining percentage contains, and it depends on the detection wavelength used. A mass spectrometry result is a separate and stronger check on identity.
The methionine residue at the start of the chain is vulnerable to oxidation, producing a sulfoxide variant. Amide bonds can also hydrolyze, though more slowly under neutral conditions. Cold storage, oxygen exclusion and minimization of freeze-thaw cycles slow both processes but do not stop them.
A purity number on a certificate does not establish that a powder is the same product as a registered nasal medicine. Counter-ion content, residual solvents and peptide-related impurities may differ between the two. Independent verification is the only way to narrow that gap.
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.