METHODS: The experiment was divided into three parts. In the first part, cells were divided into H0, H6, H12, H24, and H48 groups. In the second part, cells were divided into control group, H48 group, H48 hyperoxia+SIRT1 inhibitor group (H48+EX 527 group), and H48 hyperoxia+SIRT1 agonist group (H48+SRT1720 group). In the third part, cells were divided into control group, 48-hour hyperoxia+N-acetylcysteine group (H48+NAC group), and H48 group. The ROS kit was used to measure the level of ROS. Western blot and immunofluorescent staining were used to measure the expression levels of SIRT1 and mitochondria-related proteins. Transmission electron microscopy was used to observe the morphology of mitochondria.
RESULTS: Compared with the H0 group, the H6, H12, H24, and H48 groups had a significantly increased fluorescence intensity of ROS (P<0.05), the H48 group had significant reductions in the expression levels of SIRT1 protein and mitochondria-related proteins (P<0.05), and the H24 and H48 groups had a significant reduction in the fluorescence intensity of mitochondria-related proteins (P<0.05). Compared with the H48 group, the H48+SRT1720 group had significant increases in the expression levels of mitochondria-related proteins and the mitochondrial aspect ratio (P<0.05), and the H48+EX 527 group had a significant reduction in the mitochondrial area (P<0.05). Compared with the H48 group, the H48+NAC group had a significantly decreased fluorescence intensity of ROS (P<0.05) and significantly increased levels of SIRT1 protein, mitochondria-related proteins, mitochondrial area, and mitochondrial aspect ratio (P<0.05).
CONCLUSIONS: The ROS/SIRT1 axis is involved in hyperoxia-induced mitochondrial injury in BEAS-2B cells.
目的: 探讨活性氧簇(reactive oxygen species, ROS)/沉默信息调节因子1(silent information regulator 1, SIRT1)对高氧致BEAS-2B细胞线粒体损伤的影响。方法: 实验分为三部分:(1)细胞分为高氧0 h(H0)组、H6组、H12组、H24组、H48组。(2)细胞分为对照组、H48组、高氧48 h+SIRT1抑制剂(H48+EX 527)组和高氧48 h+SIRT1激动剂(H48+SRT1720)组。(3)细胞分为对照组、高氧48 h+乙酰半胱氨酸(H48+NAC)组和H48组。采用活性氧试剂盒检测ROS水平,Western blot法检测SIRT1和线粒体相关蛋白表达水平,免疫荧光染色法检测线粒体相关蛋白表达,透射电镜检测线粒体形态。结果: (1)与H0组相比,H6组、H12组、H24组和H48组ROS荧光强度增加(P<0.05),H48组SIRT1和线粒体相关蛋白表达水平降低(P<0.05),H24组和H48组线粒体相关蛋白荧光强度降低(P<0.05)。(2)与H48组相比,H48+SRT1720组线粒体相关蛋白表达水平升高,线粒体平均长宽比增加(P<0.05);H48+EX 527组线粒体平均面积减少(P<0.05)。(3)与H48组相比,H48+NAC组ROS荧光强度降低,SIRT1和线粒体相关蛋白表达水平升高,线粒体平均面积和平均长宽比增加(P<0.05)。结论: ROS/SIRT1轴参与了高氧诱导的BEAS-2B细胞线粒体损伤。.