The short version of heptapeptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-10-17 and is reviewed periodically as new material appears.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
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.
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.
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.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
The subject is required to touch his or her nose with eyes closed; people with normal proprioception may make an error of no more than 20 mm (0.79 in), while people with impaired proprioception (a symptom of moderate to severe alcohol intoxication) fail this test due to difficulty locating their limbs in space relative to their noses.
The tiger rattlesnake (Crotalus tigris) has a comparatively low venom yield but is considered to have the most toxic of all rattlesnake venoms, and the highest venom toxicity of all snakes in the Western Hemisphere. Although reluctant to bite, tiger rattlesnakes are known to be cantankerous and aggressive. Because of their tendency to stand their ground and aggressively defend themselves, they pose a serious threat to humans. Tiger rattlesnake venom has a high neurotoxic fraction that is antigenically related to Mojave toxin (see Crotalus scutulatus, venom A), and includes another component immunologically identical to crotamine, a myotoxin also found in tropical rattlesnakes (see Crotalus durissus). The venom has low but significant protease activity, although there does not seem to be any hemolytic activity. Brown (1973) lists an average venom yield of 11 mg (dried venom) and LD50 values of 0.07 mg/kg IP, 0.056 mg/kg IV, and 0.21 mg/kg SC. Minton and Weinstein (1984) list an average venom yield of 6.4 mg (based on two specimens). Weinstein and Smith (1990) list a venom yield of 10 mg. Humans are rarely bitten by the tiger rattlesnake, and literature available on bites by this snake is scarce. The several recorded human envenomations by tiger rattlesnakes produced little local pain, swelling, or other reaction following the bite and, despite the toxicity of its venom, no significant systemic symptoms have been recorded.
Mehal Sefari (Amharic: መኻል ሰፋሪ) was the Ethiopian title for the specialized units of the imperial guard during the reign of Emperor Menelik II. The unit originated from Emperor Menelik II’s personal guard and has occasionally been associated in oral traditions with earlier elite troops serving under Emperor Tewodros II under Fitawrari Gebeyehu, an accomplished Ethiopian military commander and lord protector of the crown, though there is no documentary evidence confirming this connection. As Gebeyehu's military unit was among the last that remained loyal to Tewodros when most of his army left, the assumption is not unreasonable if not conclusive. The title "Mehal Sefari" however was not used by any of Tewodros' units, nor by any other previous military unit. The title translates to "center campers" and alludes to the location the unit encamped in Menelik's expeditionary encampments. This organizational pattern echoed the older Ethiopian tradition of the kätäma, a mobile royal camp that served as both court and military headquarters: “The centre of power was at the time without fixed capital and the seat of the moving capital was known as kätäma.” Some have also suggested that the unit was used to come between (mehal) battling armies of the nobility; however, no historical sources substantiate this claim, as military engagements among nobles typically required imperial sanction.
She has also been involved in creating a new zebrafish model to study the role of glutathione S-transferase π1 in development, redox homeostasis, and drug response involving cytotoxicity through endoplasmic reticulum stress and unfolded protein response. Additionally, in an Antioxidants & Redox Signaling review, she analyzed the influence of the S-glutathionylation cycle on protein structure, cellular regulation, and its significance for interventions in stress- and aging-related pathologies. Furthermore, her research has demonstrated that altered GSTP expression within the endoplasmic reticulum regulates protein homeostasis (proteostasis) through S-glutathionylation of ER resident proteins, including PDI and BiP. GSTP leads to S-glutathionylation of binding immunoglobulin protein (BiP), contributing to acquired resistance to Btz in multiple myeloma (MM) cells, representing a novel mechanism of drug resistance in MM. She has also emphasized GSTπ's novel role in enhancing S-glutathionylation reactions under oxidative and nitrosative stress, with implications for stress response and drug resistance in tumors.
== Applications == Ribozymes have been proposed and developed for the treatment of disease through gene therapy. One major challenge of using RNA-based enzymes as a therapeutic is the short half-life of the catalytic RNA molecules in the body. To combat this, the 2' position on the ribose is modified to improve RNA stability. One area of ribozyme gene therapy has been the inhibition of RNA-based viruses. A type of synthetic ribozyme directed against HIV RNA called gene shears has been developed and has entered clinical testing for HIV infection. Similarly, ribozymes have been designed to target the hepatitis C virus RNA, SARS coronavirus (SARS-CoV), Adenovirus and influenza A and B virus RNA. The ribozyme is able to cleave the conserved regions of the virus's genome, which has been shown to reduce the virus in mammalian cell culture. Despite these efforts by researchers, these projects have remained in the preclinical stage.
Sources: en.wikipedia.org
Localized muscle pain Trigger points that activate the pain (MTrPs) Generally speaking, the muscular pain is steady, aching, and deep. Depending on the case and location the intensity can range from mild discomfort to excruciating and "lightning-like". Knots may be visible or felt beneath the skin. The pain does not resolve on its own, even after typical first-aid self-care such as ice, heat, and rest. Electromyography (EMG) has been used to identify abnormal motor neuron activity in the affected region. A physical exam usually reveals palpable trigger points in affected muscles and taut bands corresponding to the contracted muscles. The trigger points are exquisitely tender spots on the taut bands.
The Cherokee Nation has legislative, executive and judicial branches with executive power vested in the principal chief, legislative power in the Tribal Council, and judicial power in the Tribal Supreme Court. The principal chief, deputy chief, and tribal council are elected to four-year terms by the registered tribal voters over the age of 18. The nation's current system of government was established by the constitution of 1999, which was adopted by tribal citizens in 2003, and implemented in 2006. Every 20 years, the constitution requires a vote among tribal members, to decide whether a new constitutional convention should be held. The Congress of the United States, the federal courts, and state courts have repeatedly upheld the sovereignty of Native Tribes, defining their relationship in political rather than racial terms, and have stated it is a compelling interest of the United States. This principle of self-government and tribal sovereignty is controversial. According to the Boston College sociologist and Cherokee, Eva Marie Garroutte, up to 32 separate definitions of "Indian" are used in federal legislation, as of a 1978 congressional survey. The 1994 Federal Legislation AIRFA (American Indian Religious Freedom Act) defines an Indian as one who belongs to an Indian Tribe, which is a group that "is recognized as eligible for the special programs and services provided by the United States to Indians because of their status as Indians."
== Natural function == Capsaicin is present in large quantities in the placental tissue (which holds the seeds), the internal membranes and, to a lesser extent, the other fleshy parts of the fruits of plants in the genus Capsicum. The seeds themselves do not produce any capsaicin, although the highest concentration of capsaicin can be found in the white pith of the inner wall, where the seeds are attached. The seeds of Capsicum plants are dispersed predominantly by birds. In birds, the TRPV1 channel does not respond to capsaicin or related chemicals, but mammalian TRPV1 is very sensitive to it. This is advantageous to the plant, as chili pepper seeds consumed by birds pass through the digestive tract and can germinate later, whereas mammals have molar teeth that destroy such seeds and prevent them from germinating. Thus, natural selection may have led to increasing capsaicin production because it makes the plant less likely to be eaten by animals that do not help it disperse. There is also evidence that capsaicin may have evolved as an anti-fungal agent. The fungal pathogen Fusarium, which is known to infect wild chilies and thereby reduce seed viability, is deterred by capsaicin, which thus limits this form of predispersal seed mortality. The vanillotoxin-containing venom of a certain tarantula species (Psalmopoeus cambridgei) activates the same pathway of pain as is activated by capsaicin. It is an example of a shared pathway in both plant and animal anti-mammalian defense.
=== Saturday Night Live === In September 2005, Samberg joined Saturday Night Live as a featured player and writer. Though his live sketch roles were limited in his first year, he appeared in many prerecorded sketches including commercial parodies and various other filmed segments. On December 17, 2005, he co-starred with castmate Chris Parnell in the Digital Short show "Lazy Sunday," a hip hop song about a quest to see the film The Chronicles of Narnia: The Lion, the Witch and the Wardrobe. The short became an Internet phenomenon and garnered Samberg significant media and public attention. Acclaim continued, especially for "Dick in a Box," a duet with Justin Timberlake that won a Creative Arts Emmy for Outstanding Original Music and Lyrics. The video for his comedy troupe's collaboration with T-Pain, "I'm on a Boat," had over 56 million views on YouTube, after debuting on February 7, 2009. The song was nominated for a Grammy Award. Another digital short, "Motherlover," also featuring Timberlake, was released on May 10, 2009, to commemorate Mother's Day. Outside of his prerecorded segments, he participated in recurring live segments, such as his Blizzard Man sketch. On June 1, 2012, Samberg's spokesperson announced that Samberg had left the show. He returned to the show to host the Season 39 finale in 2014 and to star in the 40th anniversary special's Digital Short. He later returned in Season 50 to portray Doug Emhoff in the run up to the 2024 election, as well as providing some additional Digital Shorts.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.