NOX4 and Parkinson disease: In the present study, we focused on changes in the Nox4 expression level in the PD cell model and found that the expression levels of PI3K, Keap-1, Nrf2, HO-1, SOD-1 and SOD-2 were increased in the MPP+ + miR-100-5p mimics group compared to the MPP+ + mimics NC group by western blotting analysis.