Effect of Tetrapeptide Cortagen on Regeneration of Sciatic Nerve

This study evaluated the effects of Cortagen (Ala-Glu-Asp-Pro), a bioregulatory tetrapeptide derived from the cerebral cortex and developed by the Khavinson group, on sciatic nerve regeneration following experimental transection in rats. The peripheral nerve injury model used is one of the most established for evaluating neural regeneration.

Animals received intramuscular injections of Cortagen at a dose of 10 µg/kg daily for 10 days starting immediately after surgical transection of the sciatic nerve. Regeneration was assessed by electrophysiological parameters (nerve conduction velocity), morphological measures (axonal growth rate), and functional outcomes (motor recovery).

Results showed that Cortagen significantly increased the growth rate of regenerating nerve fibers by 27% and nerve conduction velocity by 40% compared to the control group. These values represent a substantial acceleration of the regenerative process, which is normally extremely slow in peripheral nerves (1-3 mm/day under basal conditions).

The proposed mechanism involves modulation of gene expression in neurons and Schwann cells (support cells of the peripheral nervous system), promoting the synthesis of neurotrophic factors and structural proteins of the axonal cytoskeleton. This study is significant for demonstrating that a peptide of only 4 amino acids, administered systemically, can influence the regeneration of a complex peripheral nerve, suggesting potential applications in traumatic and degenerative neuropathies.