Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) developed in Russia as a metabolically-stabilised analogue of the ACTH(4-10) fragment. Studied in cognitive, neuroprotection, and BDNF-signalling preclinical contexts.
Definition
Semax is a synthetic seven-amino-acid peptide (sequence Met-Glu-His-Phe-Pro-Gly-Pro) developed at the Russian Academy of Sciences as a metabolically-stabilised analogue of the ACTH(4-10) fragment of adrenocorticotropic hormone. The parent ACTH(4-10) fragment carries cognitive-modulating activity in preclinical work but is rapidly degraded in vivo; Semax adds a C-terminal Pro-Gly-Pro tripeptide tail that confers protease resistance and extends central-nervous-system bioavailability sufficiently to support intranasal administration with measurable cognitive and neurotrophic effects.
The compound is approved for clinical use in the Russian Federation under the regulatory framework for that jurisdiction. It is not approved for therapeutic use by Health Canada, the FDA, the EMA, the TGA, or other major Western regulators. Research-grade Semax is supplied as a lyophilised peptide for laboratory research applications only.
How Semax is studied in peptide research
The published mechanistic research centres on BDNF (brain-derived neurotrophic factor) signalling and its downstream TrkB receptor cascade in the hippocampus. The Dolotov characterisation documented Semax-driven regulation of BDNF and TrkB expression in the rat hippocampus with associated cognitive-modulation effects (PMID 16996037). Plasma-membrane binding and biodegradation of the heptapeptide in the rat forebrain basal nuclei was characterised in the earlier Dolotov work (PMID 15344653). Subsequent work has extended the framing into early-life fluvoxamine-exposure models documenting attenuation of behavioural and neurochemical alterations (PMID 33418449).
As with Selank, the published research base is centred predominantly in Russian research groups with comparatively limited cross-laboratory replication outside that scientific community. The pharmacology distinguishes Semax from the broader ACTH-receptor agonist class — the C-terminal stabilisation and the central-nervous-system delivery profile produce a markedly different activity spectrum from the parent ACTH(4-10) fragment despite shared sequence origin.
Related terms
- ACTH (adrenocorticotropic hormone)
- Heptapeptide
- BDNF / brain-derived neurotrophic factor
- TrkB receptor
- Hippocampus
- Intranasal administration
Where Semax appears in the Ronin catalog
- Semax 10mg — single-compound vial, lyophilized white powder under inert gas
References
- Dolotov OV et al. The binding of Semax, ACTH 4-10 heptapeptide, to plasma membranes of the rat forebrain basal nuclei and its biodegradation. Bioorg Khim 2004;30(3):241-246. [PMID 15344653]
- Dolotov OV et al. Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus. Brain Res 2006;1117(1):54-60. [PMID 16996037]
- Glazova NY et al. Semax, synthetic ACTH(4-10) analogue, attenuates behavioural and neurochemical alterations following early-life fluvoxamine exposure in white rats. Neuropeptides 2021;86:102114. [PMID 33418449]
Glossary entries describe research-context use of peptide-research terminology. They do not constitute medical, veterinary, or clinical advice. Semax is sold strictly as a research-grade reagent for laboratory and bench research applications.