Study also showed that Axin-2 shRNA- (negative regulator of Wnt/β-catenin signaling) mediated upregulation of Wnt/β-catenin signaling could enhance the net dopaminergic neurogenesis by improving behavioral functions and mitochondrial biogenesis in the SNpc, reducing apoptotic signaling, autophagy, and ROS generation, and regulating neural genes (Nurr-1, Pitx-3, Ngn-2, and NeuroD1) in PD rats [32]. This evidence concerns the gene NR4A2 and Parkinson disease.