银杏叶提取物对糖尿病模型大鼠肾脏ET-1、TGF-β_1的影响

目的:研究银杏叶提取物(EGb)对糖尿病模型大鼠肾组织中内皮素-1(ET-1)、转化生长因子β1(TGF-β1)水平变化的影响。方法:SD大鼠24只随机分为3组,即正常对照、糖尿病模型和EGb组,经相应处理后8周,观察大鼠血糖、胰岛素、总胆固醇(TC)、三酰甘油(TG)、肌酐清除率(Ccr)、尿白蛋白排泄率(UAE)、尿β2微球蛋白排泄率(β2-MG)等水平变化;以放射免疫法检测血浆、尿液及肾组织中ET-1水平;以ELISA法检测血清、尿液中TGF-β1水平。结果:糖尿病大鼠的血糖、胰岛素、TC和TG升高;经EGb治疗后,血糖、血胰岛素、TC和TG显著降低。糖尿病模型组血、尿中ET-1、TGF-β1及肾组织中ET-1水平均显著高于正常对照组;EGb可显著降低血、尿中ET-1、TGF-β1和肾组织中ET-1水平及Ccr、UAE、β2-MG。结论:EGb对糖尿病大鼠的肾脏具有保护作用,而抑制糖尿病大鼠ET-1、TGF-β1水平可能是其重要作用机制。

Protective Effect of the Extract of Ginkgo biloba on the Kidney in Diabetic Rats

OBJECTIVE:To investigate the effect of extract of Ginkgo biloba(EGb) on levels of Endothelin-1(ET-1) and transforming growth factor β1(TGF-β1) in renal tissue of diabetic rats.METHODS:Twenty-four male Sprague-Dawley rats were randomly divided into three groups:normal control group,diabetic model group and EGb-treated group.The levels of blood glucose,insulin,total cholesterol(TC),total triglycerides(TG),creatinine clearance(Ccr),urinary albumin excretion(UAE),and urinary β2-MG were measured after 8-week corresponding treatment.Expression of SET-1,UET-1,and RET-1 was examined by radioimmunoassay technique.Expression of STGF-β1 and UTGF-β1 in serum and urine was examined by enzyme linked immunosorbent assay(ELISA).RESULTS:The concentrations of blood glucose,blood insulin,TC and TG increased significantly in diabetic group,which were down-regulated by EGb.Levels of ET-1 and TGF-β1.in both blood and urine and the ET-1 level in renal tissues were significantly higher in diabetic model group than in normal control group(P<0.01).The levels of ET-1 and TGF-β1 in both blood and urine and the levels of ET-1,Ccr,UAE,and β2-MG in renal tissues were decreased significantly in EGb-treated group(P<0.05).CONCLUSION:The protective effect of EGb on kidney in diabetic rats is achieved possibly by suppressing the overexpression of ET-1 and TGF-β1.