Semax is a synthetic heptapeptide originally developed as a modified fragment of adrenocorticotropic hormone ACTH(4-7). Researchers added a C-terminal Pro-Gly-Pro tripeptide extension to the native ACTH fragment. This structural design greatly improves resistance to enzymatic degradation in biological environments and enhances its capacity to cross the blood-brain barrier. Importantly, this modification removes the endogenous corticotropic hormonal activity of full-length ACTH, so Semax does not trigger adrenal cortex stimulation, making it a specialized research reagent for neuroscience and neuroimmunology laboratory investigation.

In preclinical research models, Semax can upregulate the expression of critical neurotrophic factors including BDNF and NGF in the hippocampus and prefrontal cortex. It modulates multiple central neurotransmitter systems covering dopamine, serotonin and norepinephrine signaling pathways. Laboratory studies focus on its biological effects related to neuroplasticity, learning consolidation, working memory and sustained attention. Additional research directions include its neuroprotective properties under ischemic or traumatic brain injury conditions, regulation of neuroinflammatory response, and adaptive modulation of the central nervous system under chronic stress states. It also serves as a comparative research tool alongside Selank for exploring the functional differences of Pro-Gly-Pro capped neuropeptides.

This research-grade peptide is produced via solid-phase peptide synthesis technology. Crude peptide is purified by preparative reversed-phase HPLC, followed by sterile filtration and vacuum lyophilization to form stable dry powder. Multiple proline residues within the peptide chain contribute to better aqueous solubility and superior stability compared with ordinary linear peptides. Every production batch undergoes complete QC inspection, including HPLC purity detection, mass spectrometry identity confirmation, residual moisture test, endotoxin assay and residual solvent analysis, to ensure reliable performance for in vitro cell culture assays and animal model experiments. The N-terminal methionine residue is susceptible to oxidation, so long-term exposure to air, strong light and high temperature must be avoided during laboratory handling and sample preparation.