However, because endogenous (e.g., glutathione, coenzyme Q10, superoxide dismutase, catalase, and glutathione peroxidase) and dietary exogenous antioxidants, including vitamins A and E, can scavenge ROS, thereby diminishing oxidative stress, they presumably play a protective role in preventing PF decline and COPD development [5]. The gene discussed is CAT; the disease is chronic obstructive pulmonary disease.