Semax is a synthetic heptapeptide derived from the ACTH 4-10 fragment, studied for BDNF pathway upregulation, neuroprotective properties, and cognitive function in preclinical research models.
Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is a synthetic heptapeptide originally developed from the 4-10 fragment of adrenocorticotropic hormone (ACTH) at the Institute of Molecular Genetics of the Russian Academy of Sciences. The ACTH 4-10 sequence was identified as the portion responsible for ACTH's cognitive-enhancing effects, independent of adrenocortical activity. Semax extends this sequence with a Pro-Gly-Pro tripeptide to improve metabolic stability and CNS penetration in research settings.
Unlike full-length ACTH, Semax does not activate adrenocortical steroid synthesis, making it a selective research tool for studying the peptide's central nervous system effects in isolation. The compound is proposed to exert its primary effects through modulation of the BDNF (brain-derived neurotrophic factor) pathway and interactions with serotonin and dopamine receptor systems. Its nasal bioavailability profile — enabling CNS delivery in animal studies — has made it a useful model for intranasal peptide delivery research.
One of the most studied aspects of Semax is its interaction with BDNF signaling. Research in rodent models has shown that Semax administration upregulates BDNF expression in the hippocampus and cortex, with downstream activation of the TrkB receptor pathway. BDNF is critical for neuronal survival, synaptic plasticity, and long-term potentiation — processes central to learning and memory research. The magnitude and duration of BDNF upregulation observed with Semax has been a subject of comparative neuropeptide research.
For in-vitro research use only. Not for human or veterinary use.