益气补肾方联合雷公藤多苷对糖尿病肾病大鼠肾脏VEGF表达及血清炎症因子分泌的影响

Effect of the Union of Yiqi Bushen Fang and Tripterygium Wilfordii Polyglycosidium on Expression of VEGF and Secretion of IL-6 and TNF-α in Rats with Diabetic Nephropathy

关键词:  糖尿病肾病  益气补肾方  雷公藤多苷  血管表皮生长因子  炎症因子

Key words:  diabetic nephropathy  Yiqi Bushen Fang  Tripterygium wilfordii polyglycosidium  VEGF  inflammatory factor

摘要:

目的 观察益气补肾方联合雷公藤多苷(Tripterygium wilfordii polyglycosidium，TWP)对糖尿病肾病(diabetic nephropathy，DN)大鼠肾组织血管表皮生长因子(vascular endothelial growth factor，VEGF)表达及炎症因子分泌的作用。方法 清洁级SD大鼠60只，♂，随机分成6组，高脂饲料喂养加单侧肾切除术合链脲佐菌素(streptozocin，STZ)腹腔注射制备DN大鼠模型。第9周起，西药组以厄贝沙坦(15.75 mg·kg^-1·d^-1)、雷公藤组以TWP(3.15 mg·kg^-1·d^-1)、中药组以益气补肾方(相当于生药21.42 g·kg^-1·d^-1)、联合组以TWP加益气补肾方灌胃给药，治疗周期8周。16周末ELISA法检测大鼠血清IL-6和TNF-α水平；血糖测定仪检测大鼠血糖水平；全自动生化仪测定大鼠肾功能、尿蛋白及尿肌酐；逆转录聚合酶链反应(RT-PCR)及免疫组化技术分别检测肾组织VEGF的基因和蛋白表达；光镜及电子显微镜观察肾组织病理变化。结果 与正常组比较，造模大鼠血糖(GLU)、肌酐(Cr)、尿素氮(BUN)及尿蛋白肌酐比(P/C)明显升高(P<0.05或P<0.01)；VEGF蛋白及其mRNA表达均上调(P<0.01)；血清IL-6和TNF-α水平明显升高(P<0.05)；光镜及电镜结果提示DN大鼠足细胞数目减少、足突增宽融合，系膜增宽，基底膜增厚。与模型组比较，各治疗组大鼠血Cr、BUN和P/C均有不同程度下降(P<0.05)；血清IL-6和TNF-α水平明显下降(P<0.05)，同时VEGF蛋白及其mRNA的表达也相应有所下调(P<0.01)，同时各组病理改变也同时有改善，尤以联合治疗组效果最佳。结论 益气补肾方联合TWP能降低DN大鼠尿蛋白，保护肾功能，其作用机制可能与下调VEGF的表达及抑制炎症因子IL-6和TNF-α分泌有关。

Abstract:

OBJECTIVE To investigate the effect of the union of Yiqi bushen fang and tripterygium wilfordii polyglycosidium(TWP) on expression of VEGF and inflammatory cytokines in rats with diabetic nephropathy(DN). METHODS To establish an experimental DN rat model through a high-fat diet. Unilateral nephrectomy and injection of streptozocin(STZ) through peritoneal cavity. animals were respectively administrated with irbesartan(15.75 mg·kg^-1·d^-1), TWP(3.15 mg·kg^-1·d^-1), Yiqibu shen fang(contained 21.42 g·kg^-1·d^-1 dried medicinal herbs) and the mixture of TWP and Yiqi bushen fang from 9th week to 16th week. At the end of 16th week, the level of IL-6 and TNF-α in serum was determined by ELIAS; the level of GLU in serum were determined by glucometer; the functions of kidney and urine protein creatinine ratio (P/C) were measured with Automatic Analyzer; the expression of VEGF in renal cortex were determined with methods of RT-PCR and immunohistochemical. The pathological changes of kidney were detected with light microscope and electron microscope. RESULTS Compared with normal rats, the level of Cr, BUN, GLU in serum and urine protein of DN rats increased significantly(P<0.05); the protein and mRAN expression of VEGF in renal cortex were also increased significantly(P<0.01); the level of IL-6 and TNF-α in serum were increased significantly(P<0.05); the pathologic change showed the number of podocyte decreased, foot processes broadening and integrating, mesangial area broadening, basement membrane thickening. After the treatment, the level of Cr, BUN and P/C were decreased significantly(P<0.05); the serum level of IL-6 and TNF-α were decreased significantly(P<0.05); accompanied with the down expression of VEGF(P<0.01), and pathological changes improved, especially in union of Yiqi bushen fang and TWP treantment group. CONCLUSION The joint of Yiqi bushen fang and TWP has protection effects on early renal injury in rats with DN, and the treatment mechanism might associated with the down adjustment of the renal expression of VEGF, and inhibition of IL-6 and TNF-α secretion.