Additionally, in a mouse model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD, curcumin and its metabolite tetrahydrocurcumin (ThC), considerably reduced monoamine oxidase type B (MAO-B)-induced neurotoxicity [40]. The gene discussed is MAOB; the disease is Parkinson disease.