Semax

Semax research peptide in Thailand

Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) built from the ACTH(4-7) fragment and capped with a Pro-Gly-Pro tail, studied in neuroprotection, BDNF and NGF signalling, and cerebral ischaemia models. It is developed in Russia and appears throughout the literature under the name "ACTH(4-10) analogue", and it is commonly examined alongside Selank in neuropeptide research.

This listing is for laboratory research use only. Semax is not a medicine, nootropic, supplement, or cognitive-enhancement product.

Quick facts

Product

Semax (ACTH(4-7)-Pro-Gly-Pro heptapeptide)

CAS

80714-61-0

Molecular weight

~813.9 g/mol

Form

Lyophilised powder, sealed vial

Intended use

laboratory research use only

How Semax works

Native ACTH carries both a neurotrophic signalling region and the adrenal-stimulating region that drives cortisol release. Semax keeps only the short ACTH(4-7) core, which removes the corticotropic activity, and adds a C-terminal Pro-Gly-Pro tripeptide that slows enzymatic degradation and extends the window over which the fragment stays intact. The parent peptide itself clears from plasma within minutes; much of the activity described in the literature is attributed to this stabilised fragment and its metabolites reaching central tissue.

Mechanistically, the published work centres on neurotrophic factor expression. Studies report that Semax binds specifically to membranes in the rat basal forebrain and raises BDNF protein levels, and that it regulates both BDNF and its receptor trkB in the hippocampus. Separate rodent work describes modulation of dopaminergic and serotonergic transmission, and genome-wide analyses in focal-ischaemia models report broad shifts in immune- and vascular-related gene expression. These are findings of specific published studies, not outcomes attributed to this product.

Key research findings

• A single intranasal application of Semax increased BDNF protein and trkB expression in the rat hippocampus, with the authors linking the change to performance in avoidance learning tasks (Dolotov, Brain Research, 2006).
• In a rat model of cerebral ischaemia-reperfusion, brain protein expression profiling reported suppression of inflammatory and cell-death markers alongside activation of recovery-associated proteins (Sudarkina, Int J Mol Sci, 2021).
• Genome-wide transcriptional analysis in rat brain focal ischaemia found the immune response to be the process most markedly affected, with additional changes in vascular-system gene expression (Medvedeva, BMC Genomics, 2014).

Research applications

• Neurotrophic signalling studies (BDNF, NGF, trkB expression)
• Cerebral ischaemia and reperfusion-injury models
• Neuroprotection and neuronal survival assays under hypoxic conditions
• Dopaminergic and serotonergic pathway investigations in rodents
• Learning, memory, and avoidance-task behavioural models
• Comparative neuropeptide work alongside Selank

A note on the evidence base

Semax deserves an honest caveat that catalogue copy usually skips. It has been registered and used clinically in Russia since the 1990s, and a substantial body of clinical reporting exists — but that literature is overwhelmingly Russian-language, published in domestic journals, and has not been replicated in independent Western randomised trials. The preclinical rodent work cited above is peer-reviewed and internationally indexed; the human clinical picture is not held to the same external standard. Researchers should treat the clinical claims circulating online as unreplicated, and read the primary Russian sources directly where they matter: PubMed listings for Semax in ischaemic stroke.

Dosing in the literature

The BDNF and trkB work cited above administered the peptide intranasally rather than by injection. This is a summary of parameters as reported in research references, not administration guidance. To model concentrations for a defined protocol, use the Semax peptide calculator.

Reconstitution & storage

Solvent

Bacteriostatic water — standard for lyophilised research peptides

Mixing

Add solvent down the vial wall and swirl gently until dissolved; do not shake

Storage

Refrigerated (2–8 °C) after reconstitution, in common laboratory practice

Use within

A few weeks once reconstituted

Freeze / light

Keep lyophilised powder frozen or cold, sealed, and protected from light

Reconstitute with bacteriostatic water using sterile technique. Short peptides of this class are handled cold and kept out of direct light; in Thailand's heat and humidity, minimise ambient-temperature exposure during storage and courier handling.

Selected research

• Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus — Brain Research, 2006
• Semax, an analogue of adrenocorticotropin (4-10), binds specifically and increases levels of brain-derived neurotrophic factor protein in rat basal forebrain — Journal of Neurochemistry, 2006
• Brain Protein Expression Profile Confirms the Protective Effect of the ACTH(4-7)PGP Peptide (Semax) in a Rat Model of Cerebral Ischemia-Reperfusion — Int J Mol Sci, 2021
• Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents — Neurochemical Research, 2005
• Browse all indexed Semax literature on PubMed

Related compounds

• Selank — a synthetic tuftsin-analogue heptapeptide, also developed in Russia and also reported to affect BDNF expression; the two are frequently studied side by side because they share a development lineage but are investigated through different pathways.
• Pinealon — a short peptide bioregulator studied in neuroprotection and neuronal oxidative-stress models, a separate mechanistic approach to overlapping research questions.
• Bacteriostatic water — the standard diluent used to reconstitute lyophilised research peptides.

See also: Semax vs Selank cognitive research.

Semax FAQ

Compliance note

Semax is supplied for laboratory research use only. It is not for human or veterinary use, and it is not intended to diagnose, treat, cure, or prevent any disease. All findings referenced above are the results of specific published studies, not claims about this product.