NR4A2 and Parkinson disease: In vitro, it was found that OECs-Nurr1-Ngn2 increased the vitality of PC12 cells and inhibited oxidative stress and apoptosis. Transplantation of OECs-Nurr1-Ngn2/VMCs into vivo can improve the behavioral disorder of PD rats, and has significant neuroprotective, antioxidant and anti-apoptotic effects on PD.