HO－1对脂多糖诱导大鼠肝细胞内质网应激的作用

摘要

目的：探讨抗氧化蛋白血红素氧合酶-1（heme oxygenase-1，HO-1）对脂多糖（lipopolysaccharide， LPS）诱导大鼠肝细胞内质网应激的影响。方法大鼠正常肝细胞系BRL细胞培养，筛选有效HO-1 siRNA。用LPS、LPS+HO-1 siRNA、HO-1 siRNA和PBS溶剂分别处理大鼠肝细胞。用台盼蓝拒染实验检测细胞活力，Hoechst 33258荧光染色检测细胞凋亡，Western印迹法检测GRP78、CHOP、caspase-12以及HO-1蛋白表达。结果 LPS能剂量依赖和时间依赖性诱导大鼠肝细胞HO-1蛋白表达上调，引起GRP78、CHOP和caspase-12蛋白表达增高，细胞活力降低和细胞凋亡率增高；HO-1 siRNA预处理明显抑制LPS对HO-1蛋白表达上调的诱导作用，并加剧LPS引起的内质网应激和细胞损伤。结论 HO-1抑制LPS诱导大鼠肝细胞内质网应激介导的细胞损伤。%Objective To investigate effects of antioxidant stress protein hem e oxygenase-1 (HO-1) on lipopolysaccharide (LPS)-induced endoplasm ic reticulum stress (ERS) of rat hepatocytes. Methods The BRL cells (rat hepatocyte cell line) were cultured. The hepatocytes were treated with LPS, LPS+HO-1 si RNA , HO-1 siRNA and PB S solution, respectively. The cell viability was m easured by trypan blue ex-clusion test. The apoptosis cells were detected by the fluorescent dye Hoechst 33258. E xpressions of GR P78, C HO P, caspase-12 and HO-1 were detected by Western blotting. Results LPS caused an in-crease of HO-1 protein expression of rat hepatocytes in a dose-dependent and tim e-dependent m anner, a up-regulation of GRP78, CHO P and caspase-12, a decrease in cellviability,and an increase in apopto-sis rate of hepatocytes. Pretreatm ent of HO-1 siRNA inhibited the up-regulation of LPS-induced HO-1, however, aggravated ERS and cellular injury. Conclusion HO-1 inhibites ERS-m ediated cellular injury of rat hepatocytes induced by LPS.