ROS/COX-2调控的线粒体自噬在BCG感染巨噬细胞凋亡中的作用及机制研究OA

This study investigated the regulatory role of reactive oxygen species(ROS)/cyclooxygenase-2(COX-2)-mediated mitophagy in Bacillus Calmette-Guérin(BCG)-induced apoptosis in RAW264.7 cells.Direct immunofluorescence double staining was used to observe mitophagy levels after BCG infection,and the protein expression of PTEN-induced putative kinase 1(PINK1),RBR E3 Ubiquitin Protein Ligase(Parkin),Microtubule-associated protein light chain 3(LC3),Translocase of the outer mitochon-drial membrane 20(TOM20),and Sequestosome 1(p62)was assessed via western blotting.To examine the involvement of the PINK1/Parkin pathway,PINK1 we transfected siRNA into the cells and investigated COX-2 regulation with COX-2 siRNA.The ef-fects of reactive oxygen species(ROS)were analyzed by treatment of the cells with 5 mmol/L N-acetylcysteine(NAC).BCG infection significantly increased the colocalization of LC3 with mitochondria,while upregulating the expression of PINK1,Parkin,and LC3 II,and downregulating TOM20 and p62.The PINK1 siRNA intervention decreased BCG-induced colocalization of LC3 and TOM20;de-creased PINK1,Parkin,and LC3 II expression;and increased TOM20 expression.BCG infection also enhanced COX-2 mRNA and protein expression.Inhibition of COX-2 impaired BCG-induced activation of the PINK1/Parkin pathway and further increased apopto-sis.Treatment with NAC suppressed BCG-induced ROS elevation and activation of the COX-2/PINK1/Parkin signaling pathway.Our findings suggest that ROS/COX-2-mediated mitophagy activation plays a crucial role in attenuating BCG-induced apoptosis in RAW264.7 cells.