Effect of alpha-lipoic acid supplementation on oxidative stress markers and antioxidative defense in patients with schizophrenia.

BACKGROUND The purpose of this study was to examine the effects of alpha-lipoic acid (LA) supplementation on oxidative stress markers in patients with schizophrenia. SUBJECTS AND METHODS Eighteen (18) medicated patients with schizophrenia and 38 healthy controls received daily supplements of LA (500 mg/day) for three months. At baseline, 45th and 90th days of supplementation, venous blood collected for analysis of oxidative stress markers [superoxide anion (O2(•-)), thiobarbituric acid-reactive substances (TBARS) and advanced oxidation protein products (AOPP)] and antioxidative defense markers [superoxide dismutase (SOD), total sulfhydryl groups (-SH) and total antioxidant status (TAS)]. RESULTS Increased plasma TBARS, TAS, SH groups levels and SOD activity were found in schizophrenic patients compared to control group. LA supplementation significantly reduced TBARS, AOPP and improved TAS levels in healthy subjects, while there were no significant differences in patients group. SH groups increased after 45 days and decreased to baseline levels after 90 days of supplementation in the control group. SOD activity decreased significantly in patients group after 45 days and 90 days of supplementation. After initial rose SOD activity in control group, decreased to baseline levels found after 90 days. CONCLUSION LA supplementation decreased lipid peroxidation and oxidative damage of proteins and improved non-enzymatic antioxidant capacity in healthy controls. No significant changes were observed on oxidative damage in patients with schizophrenia.