ACTH analog raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-04-02. Anything still debated is marked as such rather than presented as settled.
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.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
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.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
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.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
=== Defense against infections === PGLYRP2 plays a limited role in host defense against infections. PGLYRP2-deficient mice are more sensitive to Pseudomonas aeruginosa-induced keratitis and Streptococcus pneumoniae-induced pneumonia and sepsis. However, PGLYRP2-deficient mice did not show a changed susceptibility to systemic Escherichia coli, Staphylococcus aureus, and Candida albicans infections or intestinal Salmonella enterica infection, although the latter was accompanied by increased inflammation in the cecum. Although PGLYRP2 is not directly bacteriolytic, it has antibacterial activity against both Gram-positive and Gram-negative bacteria and Chlamydia trachomatis. Human and mouse PGLYRP2 promote hepatitis B virus (HBV) clearance in vitro in hepatocytes and in HBV-infected mice. PGLYRP2 through its HBV DNA-binding domain recognizes covalently closed circular DNA (cccDNA) of HBV sequestering it in the nucleus and separating it from the cellular viral replication machinery. Additionally, PGLYRP2 suppresses HBV capsid assembly by directly interacting through its PGRP domain with the viral capsid and promoting secretion of the PGLYRP2-HBV capsid complexes.
dipole moment See electric dipole moment, magnetic dipole moment, molecular dipole moment, bond dipole moment, electron electric dipole moment, electron magnetic dipole moment, and nuclear magnetic moment.
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Sources: en.wikipedia.org
Coronaridine, also known as 18-carbomethoxyibogamine, is an alkaloid found in Tabernanthe iboga and related species, including Tabernaemontana divaricata for which (under the now obsolete synonym Ervatamia coronaria) it was named. Like ibogaine, (R)-coronaridine and (S)-coronaridine can decrease intake of cocaine and morphine in animals and it may have muscle relaxant and hypotensive activity.
A synovial joint, also known as diarthrosis, joins bones or cartilage with a fibrous joint capsule that is continuous with the periosteum of the joined bones, constitutes the outer boundary of a synovial cavity, and surrounds the bones' articulating surfaces. This joint unites long bones and permits free bone movement and greater mobility. The synovial cavity/joint is filled with synovial fluid. The joint capsule is made up of an outer layer of fibrous membrane, which keeps the bones together structurally, and an inner layer, the synovial membrane, which seals in the synovial fluid. They are the most common and most movable type of joint in the body. As with most other joints, synovial joints achieve movement at the point of contact of the articulating bones. Joints that are not synovial include fibrous joints such as the joints in the cranium, and cartilaginous joints such as intervertebral discs. Synovial joints originated 400 million years ago in the first jawed vertebrates.
A similar resemblance has been noted by Joanna Jurewicz, who argues that the first four nidanas resemble the Hymn of Creation (RigVeda X, 12) and other Vedic sources which describe the creation of the cosmos. Jurewicz argues that dependent origination is "a polemic" against the Vedic creation myth and that, paradoxically, "the Buddha extracted the essence of Vedic cosmogony and expressed in explicit language." Richard Gombrich agrees with this view, and argues that the first four elements of dependent origination are the Buddha's attempt to "ironize and criticize Vedic cosmogony." According to Gombrich, while in the Vedic creation theory "the universe is considered to be grounded on a primordial essence which is endowed with consciousness," the Buddha's theory avoids this essence (atman-Bahman). Jurewicz and Gombrich compare the first nidana, ignorance (avijja), with the stage before creation that is described in the Rigveda's Hymn of Creation. While the term avidya does not actually appear in this Hymn, the pre-creation stage is seen as unknowable and characterized by darkness. According to Gombrich, at this stage "consciousness is non-dual, which is to say that it is the ability to cognize but not yet consciousness of anything, for there is no split yet into subject and object." This is different from the Buddha's point of view, in which consciousness is always consciousness of something. Jurewicz then compares the Vedic creator's desire and hunger to create the atman (or "his second self") with volitional impulses (samskara).
Sources: en.wikipedia.org
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.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
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.