丁苯酞通过NLRP3炎性小体信号通路对大鼠脑缺血再灌注损伤后细胞焦亡的影响

Influences of Butyphthalide on Pyroptosis through NLRP3 Inflammasome Pathway in Rats with Cerebral Ischemia-Reperfusion Injury

目的探讨不同剂量丁苯酞通过NLRP3炎性小体信号通路对大鼠局灶性脑缺血再灌注损伤后天冬氨酸特异性半胱氨酸蛋白酶-1(caspase-1)、NOD样受体蛋白3(NLRP3)、白细胞介素-1(IL-1)蛋白表达的影响。方法将健康雄性SD大鼠50只根据随机分组法分为5组:假手术组、丁苯酞低剂量治疗组、丁苯酞中剂量治疗组、丁苯酞高剂量治疗组和模型组,各10只。采用Longa线栓法制作大鼠大脑中动脉栓塞模型,缺血2 h行再灌注,再灌注24 h后行神经功能缺损评分,氯化三苯基四氮唑(TTC)染色法检测各组大鼠的脑梗死体积,苏木素-伊红(HE)染色镜下观察各组大鼠的脑梗死病理变化,免疫组化法检测各组大鼠caspase-1、NLRP3、IL-1蛋白表达情况。结果假手术组无神经功能缺损及脑梗死。与模型组相比,丁苯酞各剂量治疗组神经功能缺损评分及脑梗死体积均减少(P<0.05)。HE染色可见假手术组核膜清晰,细胞膜完整,余各组均可见神经元数量减少,胞核溶解、固缩,胞质染色较浅,细胞水肿,但治疗组均较模型组程度轻。丁苯酞各剂量治疗组caspase-1、NLRP3、IL-1蛋白表达水平均较假手术组高(P<0.05),较模型组低(P<0.05),且存在剂量依赖性。结论丁苯酞能够通过NLRP3炎性小体信号通路改善大鼠脑缺血再灌注损伤。

Objective To observe the effect of butylphthalide on the expression of caspase-1,NLRP3,interleukin-1(IL-1)in rats with focal cerebral ischemia reperfusion(I/R)Injury through NLRP3 inflammasome Pathway.Methods Fifty male SD rats were randomly divided into five groups:sham operation group,model group,butylphthalide low-dose group,butylphthalide middle-dose group,and butylphthalide high-dose group,with 10 rats in each group.The rat model was established with the suture-occluded method introduced by Zea Longa.The rats were given reperfusion 2 hours after ischemia,and Longa score was applied to estimate the neurological function at 24 hours after reperfusion.The infarction volume was measured by TTC stain.Hematoxylin-eosin(HE)staining was used to observe the cell morphology changes.The expression of caspase-1,NLRP3,IL-1 proteins were determined by immunohistochemistry.Results There were no neurologic impairment and cerebral infarction in sham operation group.Compared with the model group,the symptoms of neurological impairment and the volume of cerebral infarction were reduced in every butyphthalide dosage group(P<0.05).HE staining revealed that,the neuron membrane was intact and clear in sham operation group;the number of neurons was decreased,nuclear was dissolved and pyknotic,cytoplasm was light-staining and cells were edematous in the other group,but the degree of treatment group was lighter than that in model group.The expression of caspase-1,NLRP3,IL-1 protein in every butyphthalide dosage group was higher than those in sham-operated group and lower than those in model group(P<0.05),and it is a dose dependence.Conclusion Butylphthalide can improve cerebral ischemia reperfusion injury through NLRP3 inflammasome pathway.