synthetic heptapeptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-08-05. Where a claim depends on a specific study, the study is described rather than over-claimed.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
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.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
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.
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.
=== Role in cognition === The Thy-1 knockout (KO) mice are viable and appear grossly normal. They display normal social interactions and normal learning in a maze, but fail to learn from social cues (e.g. learning from other mice which foods are safe to eat as compared to wild-type mice). This failure can be rescued by the transgenic expression of Thy-1 or pharmacologic treatment with a GABA (A) receptor antagonists. This suggests that Thy-1 KO mice have excessive GABAergic inhibition in the dentate gyrus and regional inhibition of long-term potentiation.
== Brand names == Brand names for Oxymetazoline include Afrin, ClariClear, Dristan, Drixine, Drixoral, Nasivin, Nasivion, Nezeril, Nostrilla, Logicin, Vicks Sinex, Visine L.R., Sudafed OM, Otrivin, Oxy, SinuFrin, Vicks Sinex Severe (Spray), and Mucinex Sinus-Max. A topical cream formulation is sold under the brand name Rhofade. Oxymetazoline ophthalmic solution for the treatment of acquired blepharoptosis is marketed as Upneeq. In the United Arab Emirates, oxymetazoline nasal sprays are sold under imported brand names such as Otrivin. The UAE does not manufacture oxymetazoline but domestic pharmaceutical companies such as Julphar produce xylometazoline, a structurally related imidazoline decongestant.
=== Cost === Irradiation is a capital-intensive technology requiring a substantial initial investment, ranging from $1 million to $5 million. In the case of large research or contract irradiation facilities, major capital costs include a radiation source, hardware (irradiator, totes and conveyors, control systems, and other auxiliary equipment), land (1 to 1.5 acres), radiation shield, and warehouse. Operating costs include salaries (for fixed and variable labor), utilities, maintenance, taxes/insurance, cobalt-60 replenishment, general utilities, and miscellaneous operating costs. Perishable food items, like fruits, vegetables and meats would still require to be handled in the cold chain, so all other supply chain costs remain the same. Food manufacturers have not embraced food irradiation because the market does not support the increased price of irradiated foods, and because of potential consumer backlash due to irradiated foods. The cost of food irradiation is influenced by dose requirements, the food's tolerance of radiation, handling conditions, i.e., packaging and stacking requirements, construction costs, financing arrangements, and other variables particular to the situation.
Official website Freeman Dyson at IMDb Appearances on C-SPAN Oral history interview transcript with Freeman Dyson on 17 December 1986, American Institute of Physics, Niels Bohr Library & Archives Freeman Dyson on INSPIRE-HEP
Sources: en.wikipedia.org
== BDNF-AS == The genomic locus encoding BDNF is structurally complex and also encodes BDNF-antisense (BDNF-AS; also known as BDNFOS or ANTI-BDNF). BDNF-AS is a long non-coding RNA (lncRNA) transcribed from the opposite strand of the BDNF gene. This lncRNA was identified in 2005 through searches in expressed sequence tag (EST) databases and subsequent RT-PCR experiments. The gene encoding BDNF-AS is located on chromosome 11p14.1. BDNF mRNA and BDNF-AS share a common overlapping region and form double-stranded RNA (dsRNA) duplexes. BDNF-AS regulates BDNF expression and can suppress BDNF mRNA. In the human neocortex, regions with increased activity and BDNF expression exhibit reduced BDNF-AS expression. Elevated BDNF-AS levels are associated with reduced BDNF expression and have been shown to promote neurotoxicity, increase apoptosis, and decrease cell viability. Conversely, inhibiting BDNF-AS upregulates BDNF mRNA, activates BDNF-mediated signaling pathways, increases BDNF protein levels, suppresses neuronal apoptosis, and promotes neuronal outgrowth and differentiation. The BDNF-AS gene consists of 10 exons and a functional promoter upstream of exon 1. The BDNF-AS gene generates numerous distinct non-coding RNAs through alternative splicing. This diversity of spliced isoforms is a common feature of eukaryotic organisms, particularly in the nervous system. Notably, BDNF-AS is absent in rodents, although highly homologous sequences are present in the genomes of chimpanzees and rhesus monkeys, suggesting a primate/hominid evolutionary origin of BDNF-AS.
Popular party substances have been reported by users to consist of aphrodisiac properties because of their enhancing effects with sexual pleasure. Ecstasy users have reported an increase in sexual desire and sexual pleasure; however, there have been reports of delayed orgasm in both sexes and erectile difficulties in men. Poppers, containing drugs for inhalation, have been linked to increased sexual pleasure. Known adverse effects are headaches, nausea, and temporary erectile difficulties.
Cold seeps and hydrothermal vents of deep oceans are communities that do not rely on photosynthesis for food and energy production. These systems are largely driven by chemosynthetic derived energy. Both systems share common characteristics such as the presence of reduced chemical compounds (H2S and hydrocarbonates), local hypoxia or even anoxia, a high abundance and metabolic activity of bacterial populations, and the production of autochthonous, organic material by chemoautotrophic bacteria. Both hydrothermal vents and cold seeps show highly increased levels of metazoan biomass in association with a low local diversity. This is explained through the presence of dense aggregations of foundation species and epizoic animals living within these aggregations. Community-level comparisons reveal that vent, seep, and organic-fall macrofauna are very distinct in terms of composition at the family level, although they share many dominant taxa among highly sulphidic habitats. However, hydrothermal vents and cold seeps also differ in many ways. Compared to the more stable cold seeps, vents are characterized by locally-high temperatures, strongly fluctuating temperatures, pH, sulfide and oxygen concentrations, often the absence of sediments, a relatively young age, and often-unpredictable conditions, such as waxing and waning of vent fluids or volcanic eruptions. Unlike hydrothermal vents, which are volatile and ephemeral environments, cold seeps emit at a slow and dependable rate.
== Genetics == Six genes have been found to be associated with the condition. These genes include BANP-ZNF469, COL4A4, FOXO1, FNDC3B, IMMP2L and RXRA-COL5A1. Others likely also exist. Patients with a parent, sibling, or child who has keratoconus have 15 to 67 times higher risk in developing corneal ectasia compared to patients with no affected relatives.
== Medical uses == Insulin icodec is used as a basal insulin to improve glycemic control in adults with diabetes. Indications vary by jurisdiction. In the United States, insulin icodec is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes. In the European Union, insulin icodec is authorized for adults with diabetes. In people with type 1 diabetes, it is indicated together with short-acting insulin to cover mealtime insulin requirements. In people with type 2 diabetes, it may be used alone or with other diabetes medicines, including short-acting insulin.
Sources: en.wikipedia.org
=== Dolls === While watching Shinjuuten no Amijima Kaname takes particular notice of the character Koharu, the doll that becomes the ideal of what Kaname thinks women should be (later to be replaced by O-hisa). The conception of womanliness that Koharu inspires in Kaname is what lies at the heart of his Madonna-Harlot conflict, and makes him attracted both to an image of the Virgin Mary and to Hollywood movie stars. He isn’t interested in real women at all, but in idealized forms of them, women who can be appreciated from afar for what they represent not for who they are. Dolls encapsulate this perfectly, being masterfully sculpted, subtle in their beauty, and silently manipulated by men.
In 2012, Kahala signed a franchising deal with Phoenix-based America's Taco Shop. In 2013, a controlling interest in Kahala Corp. was purchased by the Serruya family of Canada. The Serruyas own and founded Yogen Früz, a chain with 1400 stores around the world. At that time, Michael Serruya became Chairman and Co-CEO of Kahala Corp. Shortly thereafter, Co-CEO Kevin Blackwell left the company. The Serruya family changed the company name from Kahala Corp to Kahala Brands to better align the focus of the business. In June 2015, Kahala Brands purchased Planet Smoothie and Tasti D-Lite. This acquisition added 128 new locations to the overall company store count and increased the total of smoothie-focused locations to over 400 worldwide. Just a few months later in November 2015, Kahala Brands purchased the gourmet coffee and smoothie brand Maui Wowi. At the time of the acquisition, Maui Wowi had with 400 mobile carts and 29 standalone retail units that operated by 200 franchisees. The following month, Kahala acquired Pinkberry in December. In July 2016, MTY Food Group Inc. of Montreal, Quebec in Canada purchased Kahala Brands for approximately US$310 million. Under the deal, Kahala remained in its headquarters in Scottsdale, Arizona while MTY's US operations was moved into Kahala's offices. Kahala's Chief Operating Officer Jeff Smit was chosen to lead the US operations of the combined entity.
== Regulation of PTH secretion == Secretion of parathyroid hormone is determined chiefly by serum ionized calcium concentration through negative feedback. Parathyroid cells express calcium-sensing receptors on the cell surface. PTH is secreted when [Ca2+] is decreased (calcitonin is secreted when serum calcium levels are elevated). The G-protein-coupled calcium receptors bind extracellular calcium and may be found on the surface on a wide variety of cells distributed in the brain, heart, skin, stomach, C cells, and other tissues. In the parathyroid gland, high concentrations of extracellular calcium result in activation of the Gq G-protein coupled cascade through the action of phospholipase C. This hydrolyzes phosphatidylinositol 4,5-bisphosphate to liberate intracellular messengers IP3 and diacylglycerol (DAG). Ultimately, these two messengers result in a release of calcium from intracellular stores into the cytoplasmic space. Hence a high extracellular calcium concentration leads to an increase in the cytoplasmic calcium concentration. In contrast to the mechanism that most secretory cells use, this high cytoplasmic calcium concentration inhibits the fusion of vesicles containing granules of preformed PTH with the membrane of the parathyroid cell, and thus inhibits release of PTH. In the parathyroids, magnesium serves this role in stimulus-secretion coupling. A mild decrease in serum magnesium levels stimulates the reabsorptive activity PTH has on the kidneys.
=== Vedolizumab === Vedolizumab is very similar to natalizumab in that it is a humanized IgG monoclonal antibody, but vedolizumab is an IgG1 that specifically blocks the alpha 4 beta 7 integrin that is located primarily on cells in the gastrointestinal tract. It is promoted as being gut specific due to the localization of alpha 4 beta 7 integrin in the gastrointestinal tract and was the first biologic to be made specifically for inflammatory bowel disease.
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
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.