Effects of resveratrol on the expression of Toll-like receptor 4, NF-кB and Caspase-3 in the hippocampus of the status convulsion rat / 解剖学报

ABSTRACT

Objective To study the expression of toll-like receptor 4 (TLR4), nuclear factor κB (NF-кB) and Caspase-3 and the change of neuron apoptosis of the hippocampus in the status convulsion rat , and to explore the effect of resveratrol on them.Methods A total of 106 male Sprague-Dawley(SD)rats were randomly divided into the control (A), convulsion (B) and resveratrol treatment (C) groups.Group B was further randomly divided into four subset groups (B1-B4) which were executed at 4h, 24h, 48h, 72h after convulsion discontinued .Continuous epilepticus was induced by injecting lithium chloride and pilocarpine , and group C was daily injected with 30mg/kg resveratrol 30minutes after convulsion stopped for 3 days.TLR4 and NF-κB/p65 proteins were detected by immunohistochemistry ( IHC ); the expressions of TLR4 and Caspase-3 mRNA were detected by RT-PCR.The neuron apoptosis was observed by TUNEL . Results The IHC staining of TLR4 protein in group B was significantly higher than in group A (P<0.05), and that in group C was much lower than in B 4 group ( P<0.01 ) .The expression of NF-кB/p65 showed that hippocampal neurons had positive expression in cell nuclei in group B compared with group A (P<0.05), and the expression of NF-кB/p65 protein in group C was much lower than that in group B 4 (P<0.01).The mRNA expressions of TLR4 and Caspase-3 in the rat hippocampus of group B were significantly elevated than that in group A ( P <0.05 ) , and the tendency was increased gradually , reaching the peak at 72 hours after seizure , and that in group C was much lower than that in B 4 group (P<0.01).The TUNEL positive cells in hippocampus CAl of B group were more than that of group A after the SC 24hours (P<0.01),reached the highest level at the 72nd hour, and that in group C the TUNEL positive cells were lower than that in B4 group (P<0.01).Conclusion The expression of TLR4, NF-кB and Caspase-3 increased after SC.Resveratrol can down regulate the expression of TLR4, NF-кB and Caspase-3 in the hippocampus with pilocarpine-induced seizures, reduced the number of neuronal apoptosis .These results suggest that resveratrol may have a protective effect against the hippocampus damage caused by status convulsion .