黄芪提取物调控Nrf2/ARE信号通路对糖尿病肾病大鼠氧化应激的影响

Effects of Astragalus extract regulating Nrf2/ARE signaling pathway on oxidative stress in diabetic nephropathy rats

目的探讨黄芪提取物调控核因子E2相关因子2(Nrf2)/抗氧化反应元件(ARE)信号通路对糖尿病肾病大鼠氧化应激的影响。方法用高脂饮食联合腹腔注射链脲佐菌素法构建糖尿病大鼠模型,并随机分为模型组、高剂量+ML385组和低、高剂量实验组,每组12只;另选12只大鼠作为空白组。空白组和模型组大鼠均灌胃等体积的0.9%NaCl,低、高剂量实验组大鼠分别灌胃50、100 mg·kg^(-1)黄芪提取物,高剂量+ML385组大鼠在灌胃100 mg·kg^(-1)黄芪提取物的同时腹腔注射20 mg·kg^(-1)ML385,qd,连续8周。检测大鼠肾组织中氧化应激相关指标含量,用二氢乙啶染色法检测活性氧表达水平,用蛋白质印迹法检测大鼠肾组织中醌氧化还原酶1(NQO1)、血红素加氧酶1(HO-1)及细胞核Nrf2的蛋白相对表达水平。结果空白组、模型组、高剂量实验组和高剂量+ML385组的超氧化物歧化酶分别为(163.89±20.28)、(71.35±12.72)、(132.11±19.29)和(73.04±13.28)U·mg^(-1),谷胱甘肽过氧化物酶分别为(12.82±1.57)、(4.91±1.18)、(8.54±1.09)和(5.10±1.43)U·mg^(-1),活性氧分别为0.02±0.01、0.09±0.01、0.05±0.01和0.08±0.01,细胞核Nrf2蛋白相对表达水平分别为0.63±0.09、0.28±0.06、0.60±0.08和0.32±0.05,NQO1蛋白相对表达水平分别为0.58±0.11、0.27±0.07、0.63±0.12和0.31±0.08,HO-1蛋白相对表达水平分别为0.53±0.08、0.23±0.06、0.59±0.09和0.28±0.05。高剂量实验组的上述指标与模型组比较,在统计学上差异均有统计学意义(均P<0.05);高剂量+ML385组的上述指标与高剂量实验组比较,在统计学上差异均有统计学意义(均P<0.05)。结论黄芪提取物可以减轻糖尿病肾病大鼠氧化应激损伤,其机制可能是通过调控Nrf2/ARE信号通路实现的。

Objective To investigate the effect of Astragalus extract on oxidative stress in diabetic nephropathy rats by regulating nuclear factor E2-related factor 2(Nrf2)/antioxidant response element(ARE)signaling pathway.Methods The diabetic rat model was constructed by high-fat diet combined with intraperitoneal injection of streptozotocin,and was randomly divided into model group,experimental-L group,experimental-H group,experimental-H+ML385 group,with 12 rats in each group,and 12 rats were selected as blank group.Rats in blank group and model group were intragastric with equal volume of normal saline;rats in experimental-L,-H groups were intragastric with 50 mg·kg-1 astragalus extract and 100 mg·kg^(-1) Astragalus extract,respectively;rats in experimental-H+ML385 group were intragastric with 100 mg·kg^(-1) Astragalus extract and intraperitoneally injected with 20 mg·kg^(-1) ML385 once a day.Eight weeks in a row.The content of oxidative stress-related indexes in rat renal tissues was detected,the expression level of reactive oxygen species was detected by dihydroethidine staining,and the protein expression level of quinone oxidoreductase 1(NQO1),heme oxygenase 1(HO-1)and nuclear Nrf2 in rat renal tissues was detected by Western blot.Results Superoxide dismutase in blank group,model group,experimental-H group and experimental-H+ML385 group were(163.89±20.28),(71.35±12.72),(132.11±19.29)and(73.04±13.28)U·mg^(-1),respectively;glutathione peroxidase were(12.82±1.57),(4.91±1.18),(8.54±1.09),(5.10±1.43)U·mg^(-1),respectively;reactive oxygen species were 0.02±0.01,0.09±0.01,0.05±0.01 and 0.08±0.01,respectively;nuclear Nrf2 values were 0.63±0.09,0.28±0.06,0.60±0.08,0.32±0.05,respectively;the NQO1 values were 0.58±0.11,0.27±0.07,0.63±0.12 and 0.31±0.08,respectively;the HO-1 values were 0.53±0.08,0.23±0.06,0.59±0.09 and 0.28±0.05,respectively.Compared with the model group,the above indexes in the experimental-H group were statistically significant(all P<0.05).The above indexes of the experimental-H+ML385 group were statistically significant compared with the experimental-H group(all P<0.05).Conclusion Astragalus extract can alleviate oxidative stress damage in diabetic nephropathy rats,and the mechanism may be achieved by regulating Nrf2/ARE signaling pathway.