缺血再灌注(I/R)损伤可导致肾移植术后移植物功能延迟恢复甚至丧失。文献报道，Sirt1介导的自噬对肾脏I/R损伤具有保护作用。课题组前期研究发现，异体肾移植大鼠肾脏氧化应激及细胞凋亡率升高，细胞自噬及AMPK活性均降低；小檗碱预处理可上调细胞自噬、减少肾脏氧化应激，但具体机制不明。我们推测：小檗碱可通过上调AMPK/Sirt1通路促进自噬相关转录因子去乙酰化，增强细胞自噬，抑制线粒体依赖性细胞凋亡，减轻移植肾I/R损伤。为此，课题组拟建立大鼠异体肾移植模型，采用AMPK及Sirt1抑制剂干预，观察小檗碱预处理对肾脏细胞自噬及线粒体功能的影响；在缺氧/复氧诱导原代大鼠肾小管上皮细胞损伤模型上，我们采用基因定点突变、免疫沉淀、荧光素酶报告基因检测等方法探讨AMPK/Sirt1通路对自噬相关转录因子去乙酰化的影响，进一步阐明小檗碱发挥肾脏保护效应的分子机制，为肾移植I/R损伤的防治提供新思路。

Ischemia reperfusion (I/R) injury can lead to graft dysfunction or nonfunction after kidney transplantation. According to the literature, Sirt1 induced autophagy has protective effects against renal I/R. Our previous studies have found that allograft kidney transplantation of rats would lead to the up-regulation of oxidative stress and apoptosis. Autophagy and AMPK activity would be inhibited. Berberine could attenuate the oxidative stress level by promoting autophagy. But the related mechanism remains unclear. We hypothesize that berberine can improve the deacetylation of autophagy-related factor via activating AMPK/Sirt1 pathway, promote autophagy and inhibit mitochondria-dependent apoptosis after kidney transplantation; To test this hypothesis, we will build the allogeneic kidney transplantation model of rats and analyze the mechanism of berberine's renoprotective effect by using the inhibitors of AMPK and Sirt1. Then we intend to investigate the regulation of AMPK/Sirt1 pathway on autophagy related gene by site-directed mutagenesis, immunoprecipitation and luciferase report assays. Our study investigates berberine's protective mechanism via regulating AMPK/Sirt1 axis induced autophagy, which provides a new thought in preventing I/R injury after kidney transplantation.