SOD1 and schizophrenia: For example, in a study of 50 participants with schizophrenia (aged 18–60) and 50 controls matched for age and sex, blood samples were collected to determine SOD, MDA, glutathione, and GPx levels; schizophrenia patients had significantly lower levels of SOD and GPx, but higher levels of MDA than controls, indicating increased OS [119].