OBJECTIVETo investigate the effect of edaravone on expression of interleukin-1beta (IL-1beta), nuclear factor-kappaB (NF-kappaB) and neuron apoptosis in the juvenile rat hippocampus after status convulsion (SC).

METHODSOne hundred and ninety-five juvenile male Sprague-Dawley (SD) rats were randomly divided into normal saline (NS) control group, status convulsive group and edaravone treatment group. Each group was further divided into five subgroups for different time points. The rats in status convulsive group were kindled into epilepsy by lithium-pilocarpine chemical method. Expressions of IL-1beta and NF-kappaB proteins were detected with immunohistochemistry methods. Expression of NF-kappaB mRNA was detected with reverse transcription-polymerase chain reaction (RT-PCR). The neuron apoptosis was observed by TdT-mediated dUTP nick end labeling (TUNEL).

RESULTS(1) Measured by immunohistochemistry the value of IOD of IL-1beta (30.83 +/- 3.81, 41.00 +/- 5.61, 36.32 +/- 6.78 and 28.48 +/- 4.61, respectively, 12-72 h points) and NF-kappaB (67.60 +/- 5.81, 74.61 +/- 7.94, 82.43 +/- 10.67, 70.70 +/- 5.85 and 68.22 +/- 9.67, respectively, 4-72 h points) positive cells in the SC group increased,there was significant difference compared with NS group (IL-1beta: 11.74 +/- 2.32, 12.93 +/- 2.49, 13.02 +/- 2.83 and 12.98 +/- 5.29, respectively, 12-72 h points. NF-kappaB: 48.67 +/- 16.14, 44.62 +/- 7.82, 53.16 +/- 114.45, 54.27 +/- 5.25 and 55.56 +/- 7.56, respectively, 4-72 h points) (P < 0.01, or P < 0.05). By ED intervention in IL-1beta (22.01 +/- 4.45, 28.28 +/- 4.50 and 26.00 +/- 5.34, respectively, 12-48 h points) and NF-kappaB (58.56 +/- 6.37, 59. 86 +/- 6.73, 70.00 +/- 10.09, 64.78 +/- 7.56 and 64.45 +/- 6.51, respectively, 4-72 h points) positive cells value of the IOD decreased as compared with SC group (P < 0.01, or P < 0.05). (2) Measured by RT-PCR, the expression of NF-KB mRNA and protein trend was similar. (3)The TUNEL positive cells in hippocampus, CA1 of SC group (11.41 +/- 2.37) were more than that of NS group 12 h after the SC (P < 0.01), reached its highest level at48 h (28.78 +/- 5.11), after the intervention with edaravone (8.98 +/- 2.22, 13.09 +/- 2.54 and 20. 57 +/- 4.89, respectively, 12-48 h points) ,TUNEL positive cells showed a significant drop in SC group at 12-48 h time points (P < 0.01, or P < 0.05), but still significantly higher than that of the NS group (6.22 +/- 1.50, 6.57 +/- 1.61 and 6.72 +/- 1.14, respectively) (P < 0.01, or P < 0.05), at the 4 h time point(NS group 6.29 +/- 1.49, SC group 6.61 +/- 1.71, ED group 5.75 +/- 1.41) among the three groups, no significant difference in TUNEL positive cells was found (P = 0.759).

CONCLUSIONSEdaravone inhibited expression of IL-1beta and NF-kappaB in pilocarpine-induced seizures in rat hippocampus, reduced the number of neuronal apoptosis. These results suggest that edaravone may have protective effect against the damage caused by status convulsion.