阿托伐他汀对大鼠脑缺血再灌注损伤的保护作用及炎症机制

Protective effect of atorvastatin on cerebral ischemia-reperfusion injury in rats and its inflammatory mechanism

目的通过使用不同剂量阿托伐他汀进行预处理再制备脑缺血再灌注模型,观察阿托伐他汀对缺血性脑卒中的保护作用并初探其炎症保护机制。方法将健康雄性SD大鼠随机分为:假手术组、模型组、不同剂量阿托伐他汀组A组:5 mg/(kg·d)、B组:10 mg/(kg·d)、C组:15 mg/(kg·d)、D组:20 mg/(kg·d)。每组按再灌注不同时间点分为4个亚组。模型组和阿托伐他汀组采用线栓法制备脑缺血再灌注模型,假手术组仅暴露血管不插线栓。参照Zea-Longa 5分制评分标准进行神经功能缺损评分;2%氯化三苯四唑啉(TTC)染色测量脑梗死体积;ELISA法检测hs-CRP、TNF-α和IL-10的表达。结果(1)神经功能缺损评分:假手术组神经功能正常,模型组及各剂量组均有不同程度神经损伤,再灌注3 h及6 h,仅最高剂量阿托伐他汀组较模型组降低(P<0.05);再灌注12 h和24 h各剂量组较模型组神经评分呈剂量依赖性降低(P<0.05)。(2)脑梗死体积比较:再灌注3 h,最高剂量组与模型组比较梗死体积减小(P<0.05),再灌注6 h、12 h、24 h与模型组比较各组随剂量增加梗死体积减小(P<0.05)。(3)血清炎症因子测定:再灌注6 h、12 h、24 h模型组较假手术组hs-CRP升高,阿托伐他汀组较模型组hs-CRP降低(P<0.05),且呈剂量依赖性;各时间点模型组较假手术组TNF-α均升高(P<0.05),同一时点阿托伐他汀组较模型组TNF-α减少(P<0.05);再灌注6 h、12 h、24 h模型组较假手术组IL-10升高,与模型组比较,随阿托伐他汀剂量增加IL-10升高(P<0.05)。结论(1)阿托伐他汀能减轻大鼠局灶性脑缺血再灌注的损伤,减轻神经功能缺损症状,缩小梗死体积,这种保护作用可能与其减少hs-CRP、TNF-α增加IL-10水平有关;(2)阿托伐他汀剂量越高在抗炎保护方面作用效果最好。

Objective The protective effect of atorvastatin on ischemic stroke was observed and its protective mechanism was investigated by preconditioning cerebral ischemia reperfusion models with different doses of atorvastatin.Methods Healthy male SD rats were randomly divided into sham operation group,model group,and atorvastatin group with different doses A:5 mg/(kg·d),B:10 mg/(kg·d),C:15 mg/(kg·d),and D:20 mg/(kg·d).Each group was divided into 4 subgroups according to different time points of reperfusion.Both the model group and the atorvastatin group prepared cerebral ischemia-reperfusion model,while the sham operation group only exposed blood vessels without plug.The neurological deficits were scored according to the Zea-Longa 5 scoring standard.The volume of cerebral infarction was measured by 2%TTC staining.ELISA detected the expressions of hs-CRP,TNF-αand IL-10.Results(1)Neurological deficit score:The sham operation group had normal neurological function,the model group and each dose group had nerve injury of different degrees,and the reperfusion group had nerve injury for 3 h and 6 h,and only the highest dose atorvastatin group was lower than the model group(P<0.05).The nerve scores of each dose group at 12 h and 24 h of reperfusion showed a dose-dependent decrease compared with the model group(P<0.05).(2)Comparison of cerebral infarction volume:No cerebral infarction was observed in the sham group;all other groups had infarction lesions at 3 h after cerebral ischemia.At 3 h after reperfusion,the infarct volume in the highest dose group decreased compared with the model group(P<0.05),and at 6 h,12 h and 24 h after reperfusion,the infarct volume in each group decreased as the dose increased(P<0.05).(3)Determination of serum inflammatory factors:there was no statistically significant difference in hs-CRP between each group at 3 h of reperfusion(P>0.05).hs-CRP in the model group was increased at 6 h,12 h and 24 h after reperfusion,and decreased in the atorvastatin group compared with the sham group(P<0.05),and was dose-dependent.TNF-αin the model group was increased at all-time points compared with the sham operation group(P<0.05),and TNF-αwas decreased in the atorvastatin group compared with the model group at the same time point(P<0.05).TNF-αwas decreased with the increase of dose for 12 h and 24 h after reperfusion(P<0.05).There was no statistically significant difference in IL-10 between each group at 3 h after reperfusion(P>0.05).The levels of IL-10 in the model group at 6 h,12 h and 24 h after reperfusion were higher than those in the sham operation group.Compared with the model group,the levels of IL-10 in each dose group increased with the increase in dose(P<0.05).Conclusion(1)Atorvastatin can reduce the injury of focal cerebral ischemia-reperfusion in rats,reduce the symptoms of neurological impairment,and reduce the volume of infarction.This protective effect may be related to reducing the increased IL-10 levels of hs-CRP and TNF-α.(2)The higher the dose of atorvastatin,the better the anti-inflammatory protective effect.