普伐他汀对大鼠肾缺血再灌注损伤的保护作用及其机制探讨  

Pravastatin attenuates subsequent ischemia reperfusion injury in the rat kidney and the molecular mechanism

作　　者：金健[1] 朴尚国 金英顺[1] 金吉哲[1] 方梅荣 雷东明[1] 罗康[1] 刘金莲[1] 金华[1] 李灿[1] 

机构地区：[1]延边大学附属医院肾内科,吉林省延吉市,133000

出　　处：《中华肾脏病杂志》2014年第2期139-144,共6页Chinese Journal of Nephrology

基　　金：国家自然科学基金

摘　　要：目的明确普伐他汀（pravastatin）对大鼠肾缺血再灌注（ischemia reperfusion，IR）损伤的保护作用，并探讨其作用的分子机制。方法健康Sprague-Dawley大鼠被分为假手术组（Sham，n=5）、缺血再灌注组（IR，n=8）和普伐他汀预处理组（P＋IR，n=8）。IR组和P＋IR组大鼠给予双侧肾动脉夹闭45min后恢复灌注，术后24h后处死大鼠。P＋IR组大鼠术前1周给予普伐他汀（20mg·kg^-1·d^-1）灌胃。检测各组大鼠肾功能、体质量和血脂变化。过碘酸希夫（PAS）染色观察。肾组织病理改变；免疫组化法检测肾组织热休克蛋白70（HSP-70）的蛋白表达；TUNEL法和Western印迹法检测细胞凋亡相关蛋白Bcl-2、Bax和活性天冬氨酸特异性半胱氨酸蛋白酶3（活性Caspase-3）的变化。结果与Sham组相比，P＋IR组大鼠肾组织HSP-70蛋白表达明显增加[（173．9±19．2）％比（100．9±13．7）％，P〈0．01]。与Sham组相比，IR组大鼠Scr、血BUN水平升高（P〈0．01），肾组织坏死评分增高【（36．0±1．2）％比0，P〈0．01】，TUNEL阳性细胞数增多[（295．4±28.3）个比（1．4±1．1）个，P〈0．011。IR组大鼠肾组织Bcl-2／Bax蛋白比值下降[（57.3±7．3）％比（100．0±5．4）％，P〈0．01]，活性Caspase-3蛋白表达增高[（385．2＋38．7）％比（96．9±3．1）％，P〈0．01]。P＋IR组大鼠上述指标的改变减轻（P〈0．05）。结论普伐他汀预处理可保护大鼠肾IR损伤，其肾脏保护作用机制与诱导介质HSP．70蛋白有关，而不依赖其降脂作用。Objective To investigate the effect of pretreatment with pravastatin on subsequent ischemia reperfusion （IR） injury in rat kidney. Methods Heahh Sprague- Dawley rats were randomized into three subgroups： （1） group sham （n = 5）; （2） group IR（n = 8）; （3）group pravastatin ± [R （n = 8）. IR injury were induced by clamping both renal arteries for 45 rain. Rats were pretreated with pravastatin （20 mg·kg^-1·d^-1） for 7 d before IR injury and killed 24 h later. Renal tissues were stained with periodic acid Schiff （PAS） to measure the tubular necrosis and the heat shock protein 70 （HSP-70） expression was measured by immunohistochemistry. TUNEL assay and Western blotting were used to measure apoptotic cell death and apoptosis- related protein （Bcl- 2, Bax and active caspase- 3） expression. Results Normal rats treated with pravastatin displayed a significant increase in HSP-70 expression [（173.9±19.2）% vs （100.9±13.7）%, P 〈 0.01], which mainly located at inner cortex and outer medulla of rat kideys. Compared to group sham, the levels of BUN and Scr, tubular necrosis index [（36.0±1.2）% vs 0] and the number of TUNEL-positive cells （295.4±28.3 vs 1.4±1.1） in group IR were increased （P 〈 0.01）. In the molecular level, IR injury significantly inhibited the ratio of Bcl- 2/Bax protein [（57.3-±7.3）% vs （100.0-±5.4）%, P 〈 0.01], but increased active easpase-3 [（385.2±38.7）% vs （96.9±3.1）%, P 〈 0.01] expression. Pre-treatment with pravastatin improved all of above parameters （all P 〈 0.05）. Interestingly, there was no significant difference in serum lipid levels between experimental groups. Conclusion Pravastatin prevents against subsequent IR injury in rat kidney, and the effect is closely associated with induction of HSP-70 which is hypolipidemia-independent.

关 键 词：再灌注损伤 细胞凋亡 HSP70热休克蛋白质类 普伐他汀 

分 类 号：R965[医药卫生—药理学]