Sufentanil enhances the cortical neurogenesis of rats with traumatic brain injury via PI3K/AKT signal pathway

This study aimed to explore the effects of Sufentanil on the cortical neurogenesis of rats with traumatic brain injury (TBI) and investigate the potential mechanisms. Rats with TBI model were prepared and divided into sham + vehicle, TBI + vehicle, TBI + Sufentanil and TBI + Sufentanil + LY294002 (PI3K/AKT signal pathway inhibitor) four groups. The oxidative stress, inflammation, nerve cell damage, melatonin, brain-derived neurotrophic factor (BDNF), neuron regeneration and p-AKT protein level in the cortex were detected with ELISA, TUNEL, qRT-PCR, immunofluorescence and Western blot. Pain behavioral test was assessed with mechanical withdrawal threshold (MWT). The results showed Sufentanil significantly decreased the oxidative stress and inflammation levels, increased melatonin and BDNF levels, protected the nerve cells from damage, enhanced the regeneration of immature or mature neurons and the p-AKT protein expression in the cortex, and boosted MWT in TBI rats. While the rats with TBI were treated with LY294002 and Sufentanil together, the abovementioned effects of Sufentanil on the TBI rats were partially reversed. Our results indicate Sufentanil enhances the cortical neurogenesis and inhibits mechanical allodynia of rats with TBI through suppressing the oxidative stress, inflammation response and increasing the melatonin and BDNF levels partly via PI3K/AKT signal pathway.