通过ERK/MAPK通路观察水飞蓟素对梗阻性黄疸大鼠肝细胞凋亡的影响

To observe the effect of silymarin on hepatocyte apoptosis in rats with obstructive jaundice through ERK/MAPK pathway

目的探究水飞蓟素对梗阻性黄疸大鼠肝细胞凋亡的影响,以及对细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)/p38丝裂原活化蛋白激酶(p38 mitogen-activated protein kinase,MAPK)通路的调控机制。方法50只SD大鼠随机选取40只建立梗阻性黄疸大鼠模型,余10只大鼠为假手术组,建模成功的大鼠随机分为模型组及水飞蓟素低、中、高(50 mg/kg、100 mg/kg、200 mg/kg)剂量组,每组10只。灌胃给予药物处理,4周后检测肝功能指标;采用酶联免疫吸附试验检测白介素(interleukin,IL)-6、肿瘤坏死因子(tumor necrosis factor,TNF)-α水平;观察肝脏组织病理学变化以及肝细胞凋亡;采用免疫组化法检测肝组织胱天蛋白酶(caspase)-3、caspase-9蛋白表达;蛋白免疫印迹法检测肝组织ERK/p38MAPK通路相关蛋白表达。结果与模型组比较,水飞蓟素各剂量组大鼠的肝组织病变随药物剂量升高而逐渐减轻,且肝细胞凋亡率也逐渐降低(P<0.05);肝功能指标、IL-6、TNF-α水平、肝组织caspase-3、caspase-9蛋白表达、ERK以及p38MAPK的磷酸化水平均下降(P<0.05)。结论水飞蓟素可以降低肝细胞凋亡,改善梗阻性黄疸大鼠肝损伤,其机制可能与抑制ERK/p38MAPK通路有关。

Objective To investigate the effect of silymarin on hepatocyte apoptosis in rats with obstructive jaundice and the regulatory mechanism of extracellular signal regulated kinase(ERK)/p38 mitogen activated protein kinase(MAPK)pathway.Methods Forty SD rats were randomly selected from 50 SD rats to establish obstructive jaundice rats model,and 10 rats were set as sham operation group.The rats successfully modeled were randomly divided into model group,low(50 mg/kg),medium(100 mg/kg),and high(200 mg/kg)silymarin dose groups,with 10 rats in each group.The liver function indexes were detected after 4 weeks of drug intragastric administration.The levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-αwere measured by enzyme-linked immunosorbent assay.Liver histopathological changes and hepatocyte apoptosis were observed.The expressions of caspase-3 and caspase-9 in liver tissue were detected by immunohistochemical method.Western blotting was used to detect ERK/p38MAPK pathway-related proteins in liver.Results Compared with model group,the liver tissue lesions of rats in low,medium and high dose of silymarin groups were gradually reduced with increasing dose,and the hepatocyte apoptosis rate was decreased(P<0.05).Compared with model group,liver function indexes,IL-6,TNF-α,caspase-3,caspase-9 protein expression,ERK and p38MAPK phosphorylation levels in low,medium and high dose of silymarin groups were decreased(P<0.05).Conclusion Silymarin can reduce hepatocyte apoptosis and improve hepatic injury in rats with obstructive jaundice,and the mechanism may be related to the inhibition of ERK/p38MAPK pathway.