CAT and Parkinson disease: Catalase (CAT) and GSH-Px have antioxidant activities, and the decrease of CAT and GSH-Px levels in PD patients is an important reason for the mass production of free radicals, which accelerates the damage of dopaminergic neurons and accelerates the development of the disease (Percario et al., 2020; Leathen et al., 2022).