The effect and mechanism of lncRNA XIST targeting miR-150 on LPS-induced apoptosis and secretion of inflammatory factors in mouse lung epithelial MLE-12 cells / 西安交通大学学报(医学版)

ABSTRACT

【Objective】 To study the effect and mechanism of lncRNA XIST targeting miR-150 on LPS-induced apoptosis and secretion of inflammatory factors in MLE-12 cells. 【Methods】 Mouse lung epithelial MLE-12 cells were divided into control, LPS (LPS treatment), sh-NC+LPS (shRNA control transfection, LPS treatment), and sh-XIST+LPS (XIST shRNA transfection, LPS treatment) groups. We used qRT-PCR method to analyze and detect XIST expression level, Annexin V-FITC/PI double staining method to detect cell apoptosis, Western blotting method to analyze and detect the protein expressions of Bax and Bcl-2 in cells, TBA method to detect MDA content, Xanthine oxidation method to detect SOD activity, DCFH-DA method to detect ROS level, and ELISA method to analyze the levels of IL-1β and TNF-α in the culture supernatant. We used the bioinformatics software Starbase to analyze the possible target genes of XIST (miR-150), and then the luciferase reporter system to identify the target relationship between the two. In MLE-12 cells, XIST shRNA and miR-150 inhibitor were co-transfected, and then treated with LPS. We also measured apoptosis, oxidative damage indicators, and inflammatory factor secretion changes. 【Results】 Compared with control group, XIST level in MLE-12 cells of LPS group increased, apoptosis rate and Bax protein expression level increased, Bcl-2 protein expression level decreased, ROS and MDA level increased, SOD level decreased, and the secretion of IL-1β and TNF-α increased. Compared with the sh-NC+LPS group, the sh-XIST+LPSMLE-12 group had decreased XIST level, decreased apoptosis rate and Bax protein expression level, and increased Bcl-2 protein expression level, decreased ROS and MDA levels, increased SOD levels, and decreased IL-1β and TNF-α secreted by cells. Down-regulating XIST targeting promoted miR-150 expression. miR-150 inhibitor could reverse the effects of XIST shRNA on LPS-induced MLE-12 cell apoptosis, oxidative damage indicators, and inflammatory factor secretion. 【Conclusion】 Down-regulation of lncRNA XIST targeting miR-150 inhibits LPS-induced apoptosis and secretion of inflammatory factors in mouse lung epithelial MLE-12 cells.