局部脑缺血再灌注损伤对大鼠脑组织TLR4和NF-κB表达影响

EFFECT OF CEREBRAL ISCHEMIA-REPERFUSION ON EXPRESSION OF TLR4 AND NF-κB IN RAT BRAIN TISSUE

目的研究Toll样受体4(TLR4)和核转录因子-κB(NF-κB)在局部脑缺血再灌注模型脑组织中表达的变化。方法选择36只SD大鼠随机分为3组,分别为假手术组(S组)、对照组(C组)和菊酯组(NF-κB抑制剂,CE组),每组12只。建立局部脑缺血再灌注的大鼠模型。采用双盲法对大鼠神经功能缺损评分进行记录,应用氯化三苯基四氮唑(TTC)染色法评估大脑梗死体积,TUNEL染色法标记凋亡细胞,蛋白质印迹分析检测TLR4和NF-κB的表达。结果C组和CE组大鼠的神经功能缺损评分显著高于S组(F=16.7~189.7,P<0.01)。TTC染色结果表明,C组和CE组的脑缺血程度高于S组,CE组的脑梗死体积显著低于C组(F=271.5,P<0.01)。同时,CE组中TUNEL阳性细胞数显著低于C组(F=616.9,P<0.01)。S组大鼠NF-κB和TLR4表达水平均显著低于C组和CE组(F=279.7、884.8,P<0.01),而其在CE组大鼠表达水平显著低于C组(P<0.01)。结论NF-κB和TLR4的高表达可能与脑缺血再灌注损伤具有相关性。

Objective To study the changes in the expression of Toll-like receptor 4(TLR4)and nuclear factor-κB(NF-κB)in the brain tissue of focal cerebral ischemia-reperfusion model.Methods A total of 36 Sprague-Dawley rats were randomly divided into sham operation group(group S),control group(group C),and chrysanthemum ester group(NF-κB inhibitor,group CE),with 12 rats in each group.A rat model of focal cerebral ischemia-reperfusion was established.The double-blind me-thod was used to record the neurological deficit score of rats.The 2,3,5-triphenyltetrazolium chloride(TTC)staining of the brain slices was performed to evaluate the cerebral infarct volume.TUNEL staining was carried out to label the apoptotic cells.Western blotting analysis was used to measure the expression of TLR4 and NF-κB.Results Groups C and CE had significantly higher neurological deficit scores than group S(F=16.7-189.7,P<0.01).The TTC staining results showed that groups C and CE had higher degrees of cerebral ischemia than group S,but the cerebral infarct volume in group CE was significantly lower than that in group C(F=271.5,P<0.01).In addition,group CE had a significantly lower number of TUNEL positive cells than group C(F=616.9,P<0.01).The Western blotting results showed that group S had significantly lower expression levels of NF-κB and TLR4 than groups C and CE(F=279.7,884.8;P<0.01),and group CE had significantly lower expression levels of NF-κB and TLR4 than group C(P<0.01).Conclusion The increased expression of NF-κB and TLR4 may be related to the cerebral ischemia-reperfusion injury.