吡菲尼酮对UUO大鼠肾组织中PI3K/Akt/mTOR信号通路表达的影响

Effect of pirfenidone on PI3K/Akt/mTOR signaling pathway in UUO rats

目的探讨吡菲尼酮对单侧输尿管梗阻(UUO)大鼠肾间质纤维化过程中磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/Akt)和哺乳动物雷帕霉素靶蛋白(mTOR)信号通路表达的影响。方法选取清洁级雄性Wistar大鼠90只,按照随机数字法分为假手术组、UUO组、实验治疗组各30只。实验治疗组给予吡菲尼酮200 mg/(kg·d)灌胃,假手术组和UUO组给予等量生理盐水灌胃,1次/d,连续14 d。各组于术后第3、7、14天分别随机处死大鼠10只,留取左侧梗阻肾标本。蜡块包埋固定后,切片,采用苏木素-伊红(HE)染色检测纤维化程度,免疫组化方法测定各组及各时间点PI3K、Akt、mTOR蛋白表达含量。结果从外观上看,与UUO组相比,实验治疗组在对应时间点上梗阻肾脏肿大及积水程度较轻,色泽较红润。HE染色后观察,随着梗阻时间的延长,UUO组较假手术组肾间质纤维化改变明显,提示造模成功,且随着梗阻时间延长,纤维化程度表现出增加趋势。免疫组化染色结果显示,随梗阻时间延长,UUO组肾组织PI3K、Akt、mTOR蛋白表达逐渐增加。免疫组化结果显示,实验治疗组肾组织PI3K、Akt、mTOR表达较UUO组显著减少(P<0.05)。结论吡菲尼酮可减轻UUO大鼠肾间质纤维化,改善肾功能及降低PI3K/Akt/mTOR通路的表达,改善肾功能。

Objective To investigate the effects of pirfenidone on renal interstitial fibrosis and the expression of PI3K,Akt and mTOR signaling pathway in rats with unilateral ureteral obstruction(UUO).Methods 90 male Wistar rats were randomly divided into sham group(n=30),UUO group(n=30)and experimental group(n=30).Rats in the experimental group were given pirfenidone 200 mg/kg per day by gavage,while rats in sham group and UUO group were given the same amount of normal saline by gavage once a day for 14 days.Ten rats in each group were randomly killed on the 3rd,7th and 14th day after operation.HE staining was used to detect the degree of fibrosis.The expression levels of PI3K,Akt and mTOR protein were determined by immunohistochemistry.Results From the appearance,compared with UUO group,pirfenidone treatment group at the corresponding time point,the degree of obstructive kidney swelling and hydronephrosis was lighter,and the color was ruddy.After HE staining,the changes of renal interstitial fibrosis in UUO group were more obvious than those in model group with the prolongation of obstruction time,which indicated that the model was successfully established,and the degree of fibrosis showed an increasing trend with the prolongation of obstruction time.The expression of PI3K,Akt and mTOR in UUO group increased with the time of obstruction.Immunohistochemical results showed that the expressions of PI3K,Akt and mTOR in experimental group were lower than those in UUO group.Conclusions Pirfenidone could reduce renal interstitial fibrosis,improve renal function,and reduce the expression of PI3K/Akt/mTOR pathway in UUO rats,and improve renal function.