摘要目的 探讨内源性β-葡萄糖醛酸酶表达调解机制,为控制肝内胆管结石形成、预防结石复发提供新思路.方法 免疫组织化学染色方法检测肝内胆管结石标本中c-myc蛋白和内源性β-葡萄糖醛酸酶的表达情况;细胞培养人正常肝细胞系和肝内胆管上皮细胞系,免疫印迹(Western blot)检测脂多糖(LPS)刺激下c-myc蛋白和内源性β-葡萄糖醛酸酶的表达变化;利用siRNA验证c-myc在LPS刺激内源性β-葡萄糖醛酸酶表达增加中的作用.结果 与正常肝组织相比,肝内胆管结石肝组织中内源性β-葡萄糖醛酸酶和c-myc表达均显著增加.LPS可诱导人正常肝细胞系和肝内胆管上皮细胞系细胞内源性β-葡萄糖醛酸酶和c-myc表达增加,具有剂量依赖性;而c-myc siRNA转染可有效抑制LPS诱导的内源性β-葡萄糖醛酸酶表达增加.结论 LPS可通过c-myc刺激内源性β-葡萄糖醛酸酶表达增加,促进肝内胆管结石的形成.

abstractsObjective To study the mechanisms involved in the regulation of endogenous β-glucuronidase expression and to explore the more effective methods to prevent recurrence of hepatolithiasis formation.Methods The expression levels of c-myc and endogenous β-glucuronidase in the liver specimens of hepatolithiasis were examined by immunohistochemical staining.The expressions of c-myc and endogenous β-glucuronidase in the human intrahepatic biliary epithelial cell line (HiBEpiC),and normal liver cell line (L02) treated with different concentrations of lipopolysaccharide (LPS) were studied using western blot.The c-myc siRNA transfection was utilized to detect the role of c-myc in the regulation of the expression of endogenous β-glucuronidase.Results Compared with normal liver samples,the expressions of endogenous β-glucuronidase and c-myc in the liver specimens of hepatolithiasis were significantly increased,and they were positively correlated with each other.LPS induced increased expressions of endogenous β-glucuronidase and c-myc in a dose-dependent manner.C-myc siRNA transfection effectively inhibited the increased expression of endogenous β-glucuronidase as induced by LPS.Conclusion LPS played a crucial role in the formation of hepatolithiasis by stimulating the endogenous expression of β-glucuronidase in liver and biliary epithelial cells via c-myc.