Abstract
OBJECTIVE: To investigate the effects of TLR3 and TLR9 signaling pathway on brain injury during CPB in rats pretreated with sevoflurane and its possible molecular mechanism. METHODS: SD rats were randomly assigned to sham group, CPB group, and Sev group. Brain tissue was obtained at before CPB (T(0)), at CPB for 30 minutes (T(1)), 1 hour after CPB (T(3)), and 3 hours after CPB (T(5)). ELISA was used to measure S100-β and IL-6. Western blot was utilized to determine TLR3 and TLR9 expression. TUNEL was applied to detect neuronal apoptosis. RESULTS: Compared with CPB group, at T(1), at termination after 1 hour of CPB (T(2)), T(3), 2 hours after CPB (T(4)) and T(5), S100-β and IL-6 decreased in Sev group. Compared with CPB group, IFN-β were increased in Sev group, except T(0). Compared with CPB group, TLR3 expression increased, and TLR9 and NF-κB decreased in Sev group. The apoptotic neurons were less in Sev group than in CPB group (P < 0.05). CONCLUSION: Sevoflurane intervention can activate TLR3 and TLR9 signaling pathway, upregulate TLR3 expression and downstream TRIF expression, decrease TLR9 expression, and downregulate downstream NF-κB expression in CPB rat models, thereby mitigating brain injury induced by inflammatory response during CPB.