In this sense, Farias et al. [36], investigating the peripheral biomarkers of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in PD patients, found increased lipid hydroperoxides (LOOH), malondialdehyde (MDA) levels, and superoxide dismutase (SOD) activity, alongside decreased catalase (CAT) activity. The gene discussed is SOD1; the disease is Parkinson disease.