Peripheral non-enzymatic antioxidants in patients with schizophrenia: a case-control study

Abstract Background Recent studies show that oxidative stress is associated with the pathogenesis of schizophrenia. There are two major types of antioxidant systems in vivo, namely enzymatic antioxidants and non-enzymatic antioxidants. This study investigated differences of non-enzymatic antioxidants between schizophrenia patients and healthy controls. Methods Peripheral UA, ALB, and TBIL of 107 schizophrenic patients in the acute stage and 101 in the remission stage were measured respectively, so were 273 healthy controls. Results The levels of UA ( P  = 0.020) and TBIL ( P  < 0.001) of schizophrenic patients in the acute stage were higher than those of healthy controls, while the level of ALB ( P  < 0.001) was lower. Similar results were detected form schizophrenic patients in the remission stage. Schizophrenic patients in the acute stage were divided into antipsychotics-use subgroup ( n  = 56) and antipsychotics-naïve/free subgroup ( n  = 51). The level of UA ( P  = 0.001) in the antipsychotics-use subgroup was higher than that in the antipsychotics-naïve/free subgroup, while the level of TBIL ( P  = 0.002) was lower than that in the antipsychotics-naïve/free subgroup. Seventy-seven schizophrenic patients in the acute stage were followed up, and there was no significant difference in the level of UA before and after treatment, but levels of ALB ( P  < 0.001) and TBIL ( P  < 0.001) decreased significantly after the treatment. Conclusion This study demonstrated that the dysfunction of the peripheral non-enzymatic anti-oxidation system might be involved in the pathogenesis of schizophrenia.