Overexpression of miR-130a-3p/301a-3p attenuates high glucose-induced MPC5 podocyte dysfunction through suppression of TNF-alpha signaling

Tumor necrosis factor (TNF)-alpha has been reported to be important in glomerulonephritis, which is closely associated with podocyte dysfunction and apoptosis. However, the precise mechanisms by which TNF-alpha expression are regulated remain unclear. The purpose of the present study was to investigate the role of microRNA (miR)-130a-3p/301a-3p in the post-transcriptional control of TNF-alpha expression and high glucose (HG)-induced podocyte dysfunction. Mice MPC5 podocytes were incubated with HG and transfected with miR-130a-3p/301a-3p mimics or inhibitors, reactive oxygen species (ROS) levels were measured by flow cytometry assay, and the mRNA and protein levels were assayed by using reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The targeted genes were predicted by a bioinformatics algorithm and verified using a dual luciferase reporter assay. It was observed that miR-130a-3p/301a-3p was a novel regulator of TNF-alpha in mouse podocytes. miR-130a-3p/301a-3p mimics inhibited TNF-alpha 3'-untranslated region luciferase reporter activity, in addition to endogenous TNF-alpha protein expression. Furthermore, forced expression of miR-130a-3p or miR-301a-3p resulted in the downregulation of ROS and malondialdehyde (MDA) and the upregulation of superoxide dismutase (SOD) 1 in the presence of HG. Inhibition of TNF-alpha level prevented a remarkable reduc-tion in SOD activity and a marked increase in ROS and MDA levels in HG-treated podocytes. Furthermore, TNF-alpha loss-of-function significantly reversed HG-induced podocyte apoptosis. These data demonstrated a novel up-stream role for miR-130a-3p/301a-3p in TNF-alpha-mediated podocyte dysfunction and apoptosis in the presence of HG.