Intervention Effect of Cathepsin-B Inhibitor on Expression of Microtubule-Associated Protein 1 Light Chain 3 in Neonatal Rats Cerebral Cortex after Recurrent Seizures

Objective To explore the expression of microtubule-associated protein 1 light chain 3(LC3) in neonatal rat cerebral cortex after recurrent seizures and the intervention effect of Cathepsin-B inhibitor(CBI).Methods Six-day-old(P6) SD rats were randomly divided into 3 groups: recurrent seizure group(RS group,n=30),CBI-treated seizure group(CBI group,n=30) and control group(n=30).Rats in RS group were subjected to 5 seizures with flurothyl for 9 d,at intervals of 30 min.Rats in control group without flurotlyl.In CBI group,CBI was injected each day before seizures were induced,and with flurothyl in order to induce seizures with the same way.Western blot was employed to determine LC3 expression at different time points(1.5 h,3.0 h,6.0 h,24.0 h) and P35 after the last convulsion.Results LC3 expressions in RS group(1.5 h,3.0 h,6.0 h and 24.0 h)were significantly higher than those at the same time in control group(Pa0.05).LC3 expression in the time point(1.5 h、3.0 h、6.0 h and 24.0 h)of CBI group were significantly decreased compared with those in RS group(Pa0.05).There were no significant differences among 3 groups at P35.Conclusions Autophagy/lysosomal pathway were activated immediately after recurrent seizures as indicated by the elevated expression of LC3 in cerebral cortex.CBI was involved in the regulation of autophagy/lysosomal pathway by down-regulating the acute phase expression of LC3.