糖肾宁对KK-Ay小鼠肾脏病理及足细胞凋亡的影响

Effect of Tangshenning on renal pathology and podocyte apoptosis in KK-Ay mice

目的观察糖肾宁对KK-Ay小鼠肾脏病理及足细胞凋亡的影响。方法利用KK-Ay小鼠建立糖尿病肾病模型,将造模成功的KK-Ay小鼠随机分为模型组、糖肾宁组及缬沙坦组。另外选取相同数量的C57BL/6J小鼠作为正常对照组。糖肾宁组小鼠予20 g·kg-1·d-1的糖肾宁灌胃,缬沙坦组小鼠予10 mg·kg-1·d-1的缬沙坦灌胃,正常对照组及模型组予等剂量蒸馏水灌胃。灌胃时长为12周。分别在灌胃0、4、8、12周时检测24 h尿蛋白,灌胃12周后心尖取血检测血肌酐及尿素氮水平。HE、PAS染色观察各组小鼠肾脏病理改变,免疫组化及RT-PCR检测各组小鼠足细胞Caspase-3蛋白表达,TUNEL染色观察各组小鼠足细胞凋亡情况。结果①与正常对照组比较,模型组小鼠24 h尿蛋白、血清肌酐、尿素氮水平明显升高(P<0.05)。与模型组比较,糖肾宁组及缬沙坦组小鼠24 h尿蛋白、血清肌酐、尿素氮水平明显降低(P<0.05)。②与正常对照组比较,模型组小鼠肾小球系膜细胞增多,细胞外基质增生;与模型组比较,糖肾宁组及缬沙坦组小鼠肾小球系膜细胞减少,细胞外基质增生减轻。③与正常对照组比较,模型组小鼠足细胞Caspase-3蛋白及mRNA表达明显上调(P<0.05);与模型组比较,糖肾宁组及缬沙坦组小鼠足细胞Caspase-3蛋白及mRNA表达明显下调(P<0.05)。④与正常对照组比较,模型组小鼠足细胞凋亡数目明显升高(P<0.05);与模型组比较,糖肾宁组及缬沙坦组小鼠足细胞凋亡数目明显降低(P<0.05)。结论糖肾宁能够降低糖尿病肾病蛋白尿,改善肾功能,其机制可能与其改善肾脏病理及减轻足细胞凋亡有关。

Objective To observe the effect of Tangshenning(TSN) on renal pathology and podocyte apoptosis in diabetic nephropathy(DN) mice. Methods The DN model was established by using KK-Ay mice, and the successful modeling KK-Ay mice were randomly divided into model(DN) group, TSN group and valsartan(VST) group. In addition, the same number of C57 BL/6 J mice was selected as the normal control(NC) group. The mice in the TSN group were fed with TSN 20 g kg-1·d-1, VST group with VST 10 mg kg-1· d-1 and the normal control and DN groups with the same dose of distilled water. The duration of intragastric administration was 12 weeks. 24-hour urinary protein was detected at 0, 4, 8 and 12 weeks after intragastric administration, and blood samples from the apical heart were taken to detect the levels of serum creatinine and urea nitrogen after 12 weeks. The pathological changes of kidneys were observed by HE and PAS staining. The expression of Caspase-3 protein in podocytes was detected by immunohistochemistry and RT-PCR, and the apoptosis of podocytes was observed by TUNEL staining. Results ① Compared with the NC group,24-hour urinary protein,serum creatinine and urea nitrogen in the DN group were significantly increased(P<0.05);compared with the DN group,24-hour urinary protein,serum creatinine and urea nitrogen in the TSN and VST groups were significantly decreased(P<0.05). ②Compared with the NC group, the glomerular mesangial cells in the DN group increased and the extracellular matrix proliferated;compared with the DN group, the glomerular mesangial cells decreased and the extracellular matrix proliferation decreased in the TSN group and VST group. ③Compared with the NC group, the expression of Caspase-3 protein and mRNA in podocytes in the DN group were significantly up-regulated(P<0.05), while the expression of Caspase-3 protein and mRNA of podocytes in the TSN and VST groups were significantly down-regulated.④ Compared with the NC group,the number of podocyte apoptosis was significantly increased in the DN group(P<0.05) and that in the TSN and VST groups was significantly decreased than that in the DN group(P<0.05). Conclusion TSN can reduce proteinuria and improve renal function in mice with diabetic nephropathy, and its mechanism may be related to its improvement of renal pathology and reduction of podocyte apoptosis.