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 2026-04-03 and is reviewed periodically as new material appears.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
=== Clinical Marker === A multi-locus genetic risk score study based on a combination of 27 loci, including the COL4A1 gene, identified individuals at increased risk for both incident and recurrent coronary artery disease events, as well as an enhanced clinical benefit from statin therapy. The study was based on a community cohort study (the Malmo Diet and Cancer study) and four additional randomized controlled trials of primary prevention cohorts (JUPITER and ASCOT) and secondary prevention cohorts (CARE and PROVE IT-TIMI 22).
Cancellous bone, spongy bone, or trabecular bone is the internal tissue of the skeletal bone and is an open-cell porous network that follows the material properties of biofoams. Cancellous bone has a higher surface-area-to-volume ratio than cortical bone and it is less dense. This makes it weaker and more flexible. The greater surface area also makes it suitable for metabolic activities such as the exchange of calcium ions. Cancellous bone is typically found at the ends of long bones, near joints, and in the interior of vertebrae. Cancellous bone is highly vascular and often contains red bone marrow where hematopoiesis, the production of blood cells, occurs. The primary anatomical and functional unit of cancellous bone is the trabecula. The trabeculae are aligned towards the mechanical load distribution that a bone experiences within long bones such as the femur. As far as short bones are concerned, trabecular alignment has been studied in the vertebral pedicle. Thin formations of osteoblasts covered in endosteum create an irregular network of spaces, known as trabeculae. Within these spaces are bone marrow and hematopoietic stem cells that give rise to platelets, red blood cells and white blood cells. Trabecular marrow is composed of a network of rod- and plate-like elements that make the overall organ lighter and allow room for blood vessels and marrow. Trabecular bone accounts for the remaining 20% of total bone mass but has nearly ten times the surface area of compact bone.
== Function == Type IV collagen is a type of collagen that is responsible for providing a scaffold for stability and assembly. It is also predominantly found in extracellular basement membranes. It aids in cell adhesion, migration, survival, expansion, and differentiation.
Type I collagen production is inhibited by the inability of the altered procollagen strands to associate and form the triple-stranded, ropelike structure of mature collagen. These alterations negatively affect tissues that are rich in type I collagen, such as the skin, bones, teeth, and tendons, leading to the signs and symptoms of type III osteogenesis imperfecta. Osteogenesis imperfecta, type IV: Several different types of mutations in the COL1A1 gene cause osteogenesis imperfecta type IV. These mutations may involve missing pieces of the COL1A1 gene or changes in base pairs (the building blocks of DNA). These gene alterations result in a protein that is missing segments or has amino acid substitutions; specifically, the amino acid glycine is replaced by another amino acid. All of these changes interfere with the formation of the mature triple-stranded collagen molecule and prevent the production of mature type I collagen, which results in type IV osteogenesis imperfecta. Osteoporosis: Osteoporosis is a condition that makes bones progressively more brittle and prone to fracturing. A particular variation (polymorphism) in the COL1A1 gene appears to increase the risk of developing osteoporosis. A specific variation at Sp1 binding site is shown to be associated with increased risk of low bone mass and vertebral fracture, because of the changes the COL1A1 protein produced from one copy of the gene. Several studies have shown that women with this particular genetic variation at Sp1 site are more likely to have signs of osteoporosis than are women without the variation.
==== Effects of activity on healing ==== In animal models, extensive studies have been conducted to investigate the effects of mechanical strain in the form of activity level on tendon injury and healing. While stretching can disrupt healing during the initial inflammatory phase, it has been shown that controlled movement of the tendons after about one week following an acute injury can help to promote the synthesis of collagen by the tenocytes, leading to increased tensile strength and diameter of the healed tendons and fewer adhesions than tendons that are immobilized. In chronic tendon injuries, mechanical loading has also been shown to stimulate fibroblast proliferation and collagen synthesis along with collagen realignment, all of which promote repair and remodeling. To further support the theory that movement and activity assist in tendon healing, it has been shown that immobilization of the tendons after injury often has a negative effect on healing. In rabbits, collagen fascicles that are immobilized have shown decreased tensile strength, and immobilization also results in lower amounts of water, proteoglycans, and collagen crosslinks in the tendons. Several mechanotransduction mechanisms have been proposed as reasons for the response of tenocytes to mechanical force that enable them to alter their gene expression, protein synthesis, and cell phenotype, and eventually cause changes in tendon structure.
Sources: en.wikipedia.org
Previous columnists have included Paul Rose ("Mr Biffo", the founder of Digitiser), Toshihiro Nagoshi of Sega's Amusement Vision, author Tim Guest (whose column on MMOs preceded the publication of his book Second Lives), N'Gai Croal, and game developer Jeff Minter. In addition, numerous columns were published anonymously under the pseudonym "RedEye", and several Japanese writers contributed to a regular feature called "Something About Japan". James Hutchinson's comic strip Crashlander was featured in Edge between issues 143 and 193.
Trimebutine is a drug which is used in the treatment of irritable bowel syndrome and other gastrointestinal disorders. It is sometimes combined with simethicone as a combination drug. Trimebutine is formulated as a tablet or granules for oral suspension.
=== Surgery === Corneal transplant surgery may be difficult due to the peripheral thinning of the cornea, even with large and off-center grafts. Therefore, surgery is usually reserved for people that do not tolerate contact lenses. Several different surgical approaches may be taken, and no one approach is currently established as the standard. Examples of surgical procedures used for PMD include: wedge resection, lamellar crescentic resection, penetrating keratoplasty, lamellar keratoplasty, epikeratoplasty and intracorneal segments. Transplantation of the entire thickness of the cornea (penetrating keratoplasty) may be performed if there is enough normal tissue present. However, if there is not enough normal tissue present, then attaching the graft is difficult. New surgical techniques are in evaluation such as Intrastromal lamellar Keratoplasties and Sclerocorneal Intrastromal Lamellar Keratoplasty (SILK), these techniques allow thickening of the inferior peripheral cornea and steepening of the vertical meridien. Due to the thinning of the cornea, people with PMD are poor candidates for procedures such as LASIK and photorefractive keratectomy.
Mitochondrial disease is a group of genetic disorders caused by mitochondrial dysfunction. Mitochondria are the organelles that generate energy for the cell and are found in every cell of the human body except red blood cells. They convert the energy of food molecules into the ATP that powers most cell functions. Mitochondrial diseases take on unique characteristics both because of the way the diseases are often inherited and because mitochondria are so critical to cell function. A subclass of these diseases that have neuromuscular symptoms are known as mitochondrial myopathies. Additionally, different paradigms like intermittent fasting can improve mitochondrial health and contribute in longevity.
Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.