【摘要】 目的：探讨新型降糖药伊美格列明（Imeglimin）对棕榈酸（PA）诱导的HK-2肾小管上皮细胞脂毒性损伤的影响及机制。方法：CCK-8实验确定PA或Imeglimin的实验浓度；将HK-2细胞分为BSA组（对照组）、PA组和PA+Imeglimin组（治疗组）。油红O染色检测细胞脂滴；免疫印迹检测固醇调节元件结合蛋白-1(SREBP-1)的核转位、c-Jun氨基末端激酶（JNK）、核因子κB(NF-κB)和腺苷酸活化蛋白激酶（AMPK）的磷酸化、沉默调节蛋白1(Sirt1)、过氧化物酶体增殖物激活受体γ共激活因子-1α(PGC-1α)和沉默调节蛋白3(Sirt3)的蛋白水平；RT-qPCR检测脂肪酸合酶（FAS）和硬脂酰辅酶A去饱和酶（SCD1）的mRNA水平；试剂盒检测细胞内活性氧簇（ROS）生成、丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性。结果：选用300μmol/L PA和100μmol/L Imeglimin进行实验。与对照组相比，PA组细胞内形成大量脂滴，SREBP-1的核转位水平与FAS和SCD1的mRNA转录水平显著升高（t=4.72、10.81、28.30、22.65，均P<0.01）;JNK和NF-κB的磷酸化水平显著升高（t=23.66、18.78，均P<0.000 1）；细胞内ROS显著增加，MDA含量显著升高（t=5.54,P<0.01）,SOD活性显著降低（t=10.74,P<0.000 1）;p-AMPK/AMPK、Sirt1、PGC-1α、Sirt3的蛋白水平显著降低（t=5.40、12.02、25.97、8.67，均P<0.01）。与PA组相比，治疗组细胞内脂滴显著减少，SREBP-1的核转位水平与FAS和SCD1的mRNA转录水平显著降低（t=3.53、11.24、15.39、18.33，均P<0.05）,JNK和NF-κB的磷酸化水平显著降低（t=12.25、18.43，均P<0.001），细胞内ROS显著减少，MDA含量显著降低（t=4.22,P<0.01）,SOD活性显著升高（t=6.84,P<0.001）,p-AMPK/AMPK、Sirt1、PGC-1α、Sirt3的蛋白水平显著升高（t=5.87、7.96、11.77、6.14，均P<0.01）。结论：Imeglimin可能通过AMPK/Sirt1/PGC-1α/Sirt3信号通路改善PA诱导的HK-2肾小管上皮细胞的脂毒性损伤。更多还原

【Abstract】 Objective:To investigate the effect and mechanism of Imeglimin,a novel hypoglycemic drug,on palmitic acid(PA)-induced lipotoxicity injury in HK-2 renal tubular epithelial cells. Methods:The cell counting Kit-8(CCK-8)was used to determine the experimental concentrations of PA or Imeglimin. HK-2 cells were divided into BSA group(control group),PA group,PA+Imeglimin group(treatment group),respectively. Oil red O staining was used to detect cell lipid droplets. Western blotting was used to detect the nuclear translocation of sterol regulatory element binding protein-1(SREBP-1),the phosphorylation of c-Jun amino terminal kinase(JNK),nuclear factor κB(NF-κB)and AMP-activated protein kinase(AMPK),the protein levels of sirtuin 1(Sirt1),peroxisome pro liferator-activated receptor γ coactivator-1α(PGC-1α)and sirtuin 3(Sirt3). The RT-qPCR was used to detect the mRNA levels of fatty acid synthase(FAS)and stearoyl-CoA desaturase 1(SCD1). The corresponding kits were used to detect reactive oxygen species(ROS)generation,malondialdehyde(MDA)content and superoxide dismutase(SOD)activity. Results:300 μmol/L PA and 100 μmol/L Imeglimin were selected as the subsequent experimental concentrations. Compared with control group,a large number of lipid droplets were formed in the HK-2 cells,the nuclear translocation level of SREBP-1 and the mRNA transcription levels of FAS and SCD1 were significantly increased(t=4.72,10.81,28.30,22.65,all P<0.01),the phosphorylation levels of JNK and NF-κB were significantly increased(t=23.66,18.78,both P<0.000 1),intracellular ROS level was significantly increased,MDA content was significantly increased(t=5.54,P<0.01),SOD activity was significantly decreased(t=10.74,P<0.000 1),and the protein levels of p-AMPK/AMPK,Sirt1,PGC-1αand Sirt3 were significantly decreased(t=5.40,12.02,25.97,8.67,all P<0.01)in PA group. Compared with PA group,intracellular lipid droplets were significantly decreased,nuclear translocation level of SREBP-1 and mRNA transcription levels of FAS and SCD1 were significantly decreased(t=3.53,11.24,15.39,18.33,all P<0.05),the phosphorylation levels of JNK and NF-κB were significantly decreased(t=12.25,18.43,both P<0.001),intracellular ROS level was significantly decreased,MDA content was significantly decreased(t=4.22,P<0.01),SOD activity was significantly increased(t=6.84,P<0.001),and the protein levels of p-AMPK/AMPK,Sirt1,PGC-1α and Sirt3 were significantly increased(t=5.87,7.96,11.77,6.14,all P<0.01)in treatment group. Conclusion:Imeglimin may improve the PA-induced lipotoxicity injury in HK-2 renal tubular epithelial cells through AMPK/Sirt1/PGC-1α/Sirt3 signaling pathway.更多还原