Peripheral indices of free radical metabolism in schizophrenia

Abstract

High levels of free radicals, if not removed by specific enzymes, can damage plasma membranes. It has been proposed that free radical induced pathology may be involved in the pathogenesis of tardive dyskinesia and the defect state of schizophrenia. Data will be presented from an ongoing study examining three enzymes (superoxide dismutase, SOD; glutathione peroxidase, GSHPGD; and catalase, CAT) of free radical metabolism in schizophrenic patients. Initial findings in 11 schizophrenic patients and nine normal controls show significant differences between the groups in levels of all three enzymes. Mean SOD levels (Standard SOD Units) were significantly higher in schizophrenic patients (2449.6 + 744.5) than in normals (1025.2 ? 14) (p < .OOl), GSHPOD levels (umoYminute) were also significantly higher in patients (58.4 + 20.7) than in normals (31.2 + 3.7) (p = .OOl), while CAT levels (mmoVminute) were significantly lower in patients (7 1.8 ? 28.6) than in normals (137.9 5 30). All figures represent values per gm of Hb. There was no relation between any of the enzyme levels and either presence of TD or severity of negative symptoms. Data will be presented on a larger series of patients. The findings will be discussed with emphasis on possible clinical significance and consideration of whether the abnormal enzyme levels reflect increased free radical production, or a primary pathology of the enzyme systems independent of rate of free radical production.