红豆杉对糖尿病肾病模型大鼠PI3K/Akt信号通路的干预作用

Effect of Taxus chinensis on PI3K/Akt signaling pathway in diabetic nephropathy model rats

目的探讨红豆杉能否通过PI3K/Akt信号通路改善糖尿病肾病大鼠的肾功能,减轻肾部纤维化。方法100只SD大鼠中随机选取20只作为对照组(行腹腔手术但不摘除右肾,注射60 mg/kg体重生理盐水);剩余80只SD大鼠建立糖尿病肾病模型,造模成功后随机分为模型组、厄贝沙坦组、红豆杉组、红豆杉+LY294002组,各20只。检测各组大鼠血液和尿液样本各项指标;蛋白印迹法(Western-Blot)检测肾脏炎症损伤及PI3K/Akt信号通路相关蛋白;取各组大鼠肾脏组织,计算脏器指数;苏木素-伊红(HE)染色观察大鼠肾脏病理学改变情况;Masson染色观察大鼠肾脏胶原纤维情况。结果与对照组比较,模型组大鼠空腹血糖(FPG)、24 h尿蛋白(24 hUTP)、胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL)、血肌酐(Scr)、尿素氮(BUN)水平及血管细胞黏附分子-1(VCAM-1)、纤溶酶原激活物抑制剂1(PAI-1)蛋白表达水平、脏器指数明显升高,空腹胰岛素(INS)水平降低(P<0.05);与模型组比较,厄贝沙坦组、红豆杉组、红豆杉+LY294002组FPG、24 hUTP、TC、TG、LDL、Scr、BUN水平及VCAM-1和PAI-1蛋白表达水平、脏器指数明显降低,INS水平升高(P<0.05),其中红豆杉+LY294002组改变最为明显(P<0.05)。染色结果显示,与模型组比较,厄贝沙坦组、红豆杉组、红豆杉+LY294002组大鼠的肾间质和肾小管病理改善明显,肾小体肿胀减轻明显,大鼠的肾小球和肾小管间质中蓝色胶原纤维明显减少,其中红豆杉+LY294002组大鼠肾间质和肾小管病理改变、肾小体肿胀、肾脏纤维化改善情况最明显。与对照组比较,模型组大鼠肾组织中p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR的比值明显升高(P<0.05);与模型组比较,厄贝沙坦组、红豆杉组、红豆杉+LY294002组大鼠肾组织中p-PI3K/PI3K、p-AKT/AKT、p-mTOR/mTOR的比值明显降低(P<0.05),其中红豆杉+LY294002组最明显(P<0.05)。结论红豆杉可能通过抑制PI3K/Akt信号通路改善糖尿病肾病大鼠的肾功能,降低炎症反应,减轻肾部纤维化。

Objective To explore whether Taxus chinensis can improve renal function and alleviate renal fibrosis in diabetes rats through PI3K/Akt signaling pathway.Methods20 out of 100 SD rats were randomly selected as control group(abdominal surgery without right kidney removal,injection of 60 mg/kg body weight saline).The remaining 80 SD rats were established diabetic nephropathy model.After successful modeling,they were randomly divided into model group,Irbesartan group,Taxus chinensis group and Taxus chinensis+LY294002 group,with 20 rats in each group.Blood and urine samples were collected and tested in each group.Western-blot was used to detect renal inflammatory injury related proteins and PI3K/Akt signaling pathway related proteins.The kidney tissue of the each group was removed and the kidney index was calculated.Hematoxylin eosin(HE)staining was used to observe pathological changes in the kidneys of the rats,while Masson staining was used to observe the collagen fibers in kidneys of the rats.ResultsCompared with the control group,the levels of FPG,24-hour UTP,TC,TG,LDL,Scr,BUN,VCAM-1 and PAI-1 protein expression,organ index were increased,while INS levels decreased in the model group(P<0.05).Compared with the model group,the levels of FPG,24 hUTP,TC,TG,LDL,Scr,BUN,VCAM-1 and PAI-1 protein expression,organ index were decreased,and INS level increased in the Irbesartan group,Taxus chinensis group,and Taxus chinensis+LY294002 group(P<0.05),and Taxus chinensis+LY294002 group was the most significant(P<0.05).Compared with the model group,the pathological changes of renal interstitium and tubules of the rats in the Irbesartan group,Taxus chinensis group and Taxus chinensis+LY294002 group were significantly improved,the swelling of renal corpuscle was significantly reduced,and the blue collagen fibers in the glomerulus and tubulointerstitium of the rats were significantly reduced.In the Taxus chinensis+LY294002 group,the pathological changes of renal interstitium and tubules were the most obvious,the swelling of renal corpuscle was the most obvious,and the renal fibrosis was more obvious.Compared with the control group,the ratio of p-PI3K/PI3K,p-AKT/AKT and p-mTOR/mTOR in the renal tissue of the model group rats were significantly increased(P<0.05).Compared with the model group,the ratios of p-PI3K/PI3K,p-AKT/AKT,p-mTOR/mTOR in kidney tissue of the rats in Irbesartan group,Taxus chinensis group and Taxus chinensis+LY294002 group were significantly lower(P<0.05),and Taxus chinensis+LY294002 group was the most significant(P<0.05).ConclusionTaxus may improve renal function,reduce inflammation and reduce renal fibrosis in rats with diabetic nephropathy by inhibiting the PI3K/AKT signaling pathway.