The absence of Nrf2 produces a greater loss of dopaminergic neurons in the substantia nigra, inflammation, and severe astrogliosis and microgliosis in a Parkinson’s disease (PD) rodent model induced by 1-methy-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a potent neurotoxin. The gene discussed is NFE2L2; the disease is Parkinson disease.