Upregulation of miR-210-5p impairs dead cell clearance by macrophages through the inhibition of Sp1-and HSCARG-dependent NADPH oxidase pathway.

The deficiency of dead cell clearance is a prominent pathogenic factor in systemic lupus erythematosus (SLE). In this study, the overexpression of miR-210-5p resulted in the accumulation of secondary necrotic cells (SNECs) in macrophages through the reduction of protein degradation. The upreguation of miR-210-5p inhibited NADPH oxidase (NOX) activation, reactive oxygen species (ROS) generation, and SNEC clearance. miR-210-5p overexpression suppressed Sp1 and HSCARG expression, and the knockdown of SP1 and HSCARG inhibited NOX expression and superoxide production in macrophages. Furthermore, patients with active SLE expressed a higher level of miR-210-5p and lower expression of SP1 and HSCARG in peripheral blood mononuclear cells. In summary, our findings indicate that the upregulation of miR-210-5p increases the accumulation of SNECs through a decrease in the Sp1-and HSCARG-mediated NOX activity and ROS generation in macrophages. Our results also suggest that targeting miR-210-5p may have therapeutic potential for SLE.