Plasma antioxidant status and motor features inde novoChinese Parkinson's disease patients

Abstract
This study aimed to explore plasma antioxidant status in de novo Chinese Parkinson's disease (PD) patients and investigate its relationship with specific motor features of PD. Sixty-four de novo Chinese PD patients and 40 age- and sex-matched healthy controls were recruited. Each motor feature of PD patients was assessed by unified Parkinson's disease rating scale. Plasma antioxidant status, including plasma level of glutathione (GSH) and plasma activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), was detected using enzyme-linked immunosorbent assay. The relationship between the plasma antioxidant status and motor features of PD was evaluated by Spearman's coefficient. Plasma GSH level and plasma activities of GSH-Px, CAT and SOD of PD patients were lower than those of healthy controls. Moreover, the declining activity of plasma CAT was related with the increasing mean postural instability and gait disorder (PIGD) score and growing age. In contrast, the severity of tremor was positively correlated with plasma SOD activity. Our study demonstrates that the plasma antioxidant status is impaired in de novo Chinese PD patients. The complex relationship between the plasma antioxidant status and different motor features indicates that the antioxidant mechanisms underlying tremor and PIGD of PD may be different.