青藤碱对阿霉素诱导的局灶节段肾小球硬化大鼠足细胞损伤的干预作用及机制分析

The interventional effects and mechanistic analysis of sinomenine on adriamycin induced podocyte injury in focal segmental glomerulosclerosis rats

目的探讨青藤碱对阿霉素诱导的局灶节段肾小球硬化大鼠的干预作用及其机制。方法采用单侧肾切除术加两次尾静脉注射阿霉素建立局灶节段肾小球硬化模型。将大鼠随机分为正常组,模型组,青藤碱低、中、高剂量组和FK506组,干预4周。检测24 h尿蛋白、血生化、肾组织病理,免疫组化检测肾组织Podocin和TRPC6,Western blot检测Nephrin、Podocin和TRPC6表达,电镜观察肾小球微观结构。结果与正常组比较,模型组大鼠24 h尿蛋白量明显升高(P<0.05),血白蛋白明显减少(P<0.05)。经青藤碱低、中、高剂量干预后,24 h尿蛋白量呈剂量依赖性降低,血白蛋白呈剂量依赖性升高,FK506组24 h尿蛋白量亦显著下降,血白蛋白显著升高(P<0.05)。免疫组化和Western blot提示模型组肾组织Podocin、Nephrin表达显著下降,TRPC6表达显著升高,经青藤碱低、中、高剂量干预后,Podocin、Nephrin呈剂量依赖性升高,TRPC6呈剂量依赖性下降,FK506组Podocin、Nephrin表达亦显著升高,TRPC6表达下降(P<0.05)。模型组电镜下肾小球足突广泛融合,经青藤碱或FK506干预后,足细胞融合减轻。结论青藤碱可能通过下调TRPC6表达对足细胞损伤进行修复,进而减轻肾组织病理改变。

Objective To study the effects and mechanism of sinomenine on adriamycin induced focal segmental glomerulosclerosis(FSGS)rats.Methods Unilateral nephrectomy plus two tail vein injections of adriamycin was used to establish FSGS model.Wistar rats were randomly divided into the normal group,the model group and sinomenine low dose,medium dose and high dose group,calmodulin inhibitor(FK506)group,received intervention for a total of four weeks.24 h urinary protein,blood biochemical index and renal tissue pathology were measures at the end of the study.Glomerular Podocin and TRPC6 expression were detected using immunohistochemical method.Nephrin,Podocin and TRPC6 expression were also measured using western blot.Renal microstructure were explored under electron microscope.Results Compared with the normal group,24-hour urinary protein in the model group was significantly increased,serum albumin was significantly decreased(P<0.05).24-hour urinary protein in the low-dose,medium-dose,and highdose groups of sinomenine were dose-dependently reduced,serum albumin levels were dose-dependently increased(P<0.05).24-hour urinary protein level in the FK506 group was significantly decreased,serum albumin level was significantly increased(P<0.05).Compared with the normal group,glomerular Podocin,Nephrin expression were significantly decreased,TRPC6 expression was significantly increased in the model group(P<0.05).Podocin,Nephrin expression in the low-dose,medium-dose,and high-dose sinomenine group was dose-dependently increased,TRPC6 expression was dose-dependently decreased(P<0.05).The FK506 group was similar.Electron microscopy showed extensive fusion of podocyte foot processes in the model group,which was alleviated by sinomenine or FK506 intervention.Conclusion Sinomenine may repair podocyte injury by downregulating TRPC6 expression in a dose-dependent manner to alleviate renal injury.