Semax
A synthetic ACTH(4-7)-derived heptapeptide studied for neurotrophic gene expression and neuroprotection in laboratory models.
Overview
Semax is a synthetic heptapeptide first developed in the 1980s at the Institute of Molecular Genetics of the Russian Academy of Sciences. Its structure corresponds to the ACTH(4-7) fragment of adrenocorticotropic hormone (the Met-Glu-His-Phe core associated with the non-hormonal, behavioural activity of ACTH), extended at the C-terminus with the stabilising tripeptide Pro-Gly-Pro. It is commonly described in the literature as an analogue related to the ACTH(4-10) fragment region.
The appended Pro-Gly-Pro tail is understood to slow enzymatic degradation, extending the molecule's residence time relative to the native fragment. Despite being derived from ACTH, Semax is reported to be devoid of corticotropic (hormonal) activity in research models. In the research setting it is studied as a neuropeptide of interest for neurotrophic expression and neuroprotection endpoints.
Molecular Profile
Mechanism of Action
Findings below are drawn from published in-vitro and animal-model research:
- BDNF and TrkB up-regulation: In rodent hippocampal and basal-forebrain studies, Semax has been reported to increase BDNF mRNA and protein alongside changes in TrkB expression, implicating the neurotrophin/TrkB signalling axis (Dolotov et al., 2006; Agapova et al., 2007).
- Induction of NGF and neurotrophin transcripts: Real-time PCR studies in rat brain report rapid, region-specific activation of NGF and BDNF gene expression following Semax exposure, with differing time-courses across hippocampus, frontal cortex, and retina.
- Neuroprotective gene programs in ischaemia: In cerebral-ischaemia models, Semax and its Pro-Gly-Pro metabolite have been reported to influence transcription of neurotrophins and their receptors and to suppress pro-inflammatory mediator transcripts.
- Monoaminergic modulation: Review-level literature describes modulatory effects on serotonergic and dopaminergic systems in animal models, reported as modulatory mechanistic context rather than direct stimulation.
Key Published Research
Semax, an analogue of ACTH(4-10), binds specifically and increases levels of brain-derived neurotrophic factor protein in rat basal forebrain
Dolotov OV, et al. Journal of Neurochemistry. 2006; 97 Suppl 1:82-86 (PMID 16635254)
Reports specific binding of Semax in rat basal forebrain and increased BDNF protein levels, a foundational study linking Semax to the neurotrophin system.
Neurotrophin gene expression in rat brain under the action of Semax, an analogue of ACTH 4-10
Agapova TY, et al. Neuroscience Letters. 2007; 417(2):201-205
Demonstrates rapid changes in BDNF/NGF gene expression in rat brain following Semax administration, measured by real-time PCR.
Comparison of the temporary dynamics of NGF and BDNF gene expression in rat hippocampus, frontal cortex, and retina under Semax action
Shadrina MI, et al. Journal of Molecular Neuroscience. 2009; 39(3)
Maps the time-course of NGF and BDNF gene-expression changes across three CNS regions, showing region-specific regulation.
Storage and Handling
Lyophilised (unreconstituted):Store at -20°C for long-term stability. Keep sealed and protected from light and moisture.
Reconstituted:Store at 2-8°C. Use within 30 days. Avoid repeated freeze-thaw cycles.
Recommended solvent: Bacteriostatic water or sterile water for laboratory use.
Frequently Asked Questions
What is the structural relationship between Semax and ACTH?
Semax corresponds to the ACTH(4-7) core (Met-Glu-His-Phe) with a C-terminal Pro-Gly-Pro extension, and is described in the literature as related to the ACTH(4-10) fragment region. Research reports indicate it lacks the corticotropic activity of full-length ACTH.
Which research endpoints is Semax most associated with?
In published in-vitro and animal studies it is most frequently examined for neurotrophin (BDNF/NGF) gene and protein expression, TrkB-axis signalling, and neuroprotective gene programs in ischaemia models.
What purity and form does ERC supply for research?
Lyophilised powder at ≥98% HPLC purity, intended strictly for in-vitro laboratory research only.
Disclaimer: This information is compiled from published peer-reviewed literature and is provided for educational and research reference purposes only. It does not constitute medical advice. Semax sold by Enhanced Research Compounds is intended exclusively for in-vitro research and laboratory use. It is not a therapeutic good, is not listed on the ARTG, and is not approved for human or animal consumption.