异丙酚和白藜芦醇预处理对大鼠肝脏缺血再灌注损伤时细胞凋亡的影响及机制

Protective effect of propofol and resveratrol pretreatment against hepatocyte apoptosis in rats with hepatic ischemia-reperfusion injury

目的探讨异丙酚与白藜芦醇单独应用及联合应用预处理对大鼠肝脏缺血再灌注损伤细胞凋亡的影响及可能的作用机制。方法 144只健康成年雄性SD大鼠随机分为8组,18只/组,分别为:假手术组(SO组)、生理盐水预处理组(NS组)、Tween80预处理组(TW组)、低剂量异丙酚预处理组(PROⅠ组)、高剂量异丙酚预处理组(PROⅡ组)、低剂量白藜芦醇预处理组(RESⅠ组)、高剂量白藜芦醇预处理组(RESⅡ组)、异丙酚联合白藜芦醇预处理组(PRO+RES组)。参照Pringle法建立大鼠全肝缺血再灌注模型。SO组仅游离肝门,不作肝门阻断,经股静脉输注生理盐水(2 ml/kg);NS组、TW组分别于肝门阻断前10 min经股静脉输注生理盐水(2 ml/kg)、Tween80(2 ml/kg);PROⅠ组、PROⅡ组、RESⅠ组、RESⅡ组及PRO+RES组分别于肝门阻断前10 min经股静脉输注异丙酚10 mg·kg-1·h-1、异丙酚20 mg·kg-1·h-1、白藜芦醇10 mg/kg、白藜芦醇20 mg/kg、异丙酚10 mg·kg-·1h-1+白藜芦醇10 mg/kg。各实验组均于再灌注后1、3、6 h分别处死6只动物,留取肝组织标本,常规石蜡包埋后切片。HE染色观察肝组织形态学改变,原位细胞凋亡检测技术(TUNEL法)检测肝组织细胞凋亡情况;免疫组织化学技术检测肝组织凋亡相关蛋白Bcl-2、Bax及caspase-3蛋白的表达。结果与NS组、TW组比较,PROⅠ组、PROⅡ组、RESⅠ组、RESⅡ组及PRO+RES组肝组织病理损害减轻,细胞凋亡指数降低(P<0.05),Bcl-2蛋白表达增多(P<0.05),Bax及caspase-3蛋白表达减少(P<0.05)。相较于PROⅠ组及RESⅠ组,PRO+RES组肝组织病理损伤减轻,细胞凋亡指数降低(P<0.05),Bcl-2蛋白表达增多(P<0.05),Bax蛋白及caspase-3蛋白表达减少(P<0.05)。PROⅡ组、RESⅡ组与PRO+RES组间肝组织病理损伤程度、细胞凋亡指数及细胞凋亡相关蛋白表达无显著差异。结论异丙酚与白藜芦醇通过上调Bcl-2蛋白的表达,下调Bax及caspase-3蛋白的表达,抑制细胞凋亡,对HIRI产生一定的保护作用。异丙酚与白藜芦醇联合应用可以明显减少用药剂量。

Objective To observe the effect of resveratrol and propofol, used either alone or in combination, on hepatocyte apoptosis in rats with hepatic ischemia-reperfusion injury （HIRI）. Methods A total of 144 male SD rats were randomized into 8 equal groups, including a sham-operated group and 7 HIRI （established using Pringle method） groups with pretreatments with normal saline, Tween80, propofol （10 or 20 mg·kg^-1·h^-1）, or resveratrol （10 or 20 mg/kg）, or both propofol and resveratrol 10 min before hepatic portal vein occlusion. At 1, 3 and 6 h after the reperfusion, 6 rats from each group were sacrificed for histopathological examination of the liver tissue, detection of hepatocyte apoptosis using TUNEL assay, and measurement of Bcl-2, Bax and caspase-3 protein expressions using immunohistochemistry. Results Compared with normal saline and Tween80, propofol and resveratrol at different doses used alone or in combination all significantly alleviated the hepatic pathologies, lowered the apoptosis index （P〈0.05）, increased Bcl-2 expression （P〈0.05）, and reduced Bax and caspase-3 expressions in the liver tissues following HIRI （P〈0.05）. Compared with low doses of propofol and resveratrol used alone, their combination showed more obvious protective effects against hepatocyte apoptosis （P〈0.05）, but at higher doses, propofol and resveratrol either alone or in combination produced similar effects. Conclusions Propofol and resveratrol can suppress HIRI-induced hepatocyte apoptosis by up-regulating Bcl-2 and down-regulating Bax and caspase-3 expressions, and their combined use can reduce the effective doses of the drugs.