Neutrophil function, nitric oxide, and blood oxidative stress in Parkinson's disease

Abstract

AbstractWe studied nitrogen radical nitric oxide (.NO) release and reactive oxygen species (ROS) production by isolated neurophils after phorbol myristate acetate (PMA) stimulation in 12 newly diagnosed and nine treated Parkinson's disease (PD) patients and 10 age‐matched healthy controls. Neutrophils of both groups of PD patients had an elecated PMA‐activated release of ·NO [61 and 57%, respectively, higher than that of controls (p < 0.05)]. In contrast, H2O2 release was only significantly increased by 56% in chronically treated patients. In agreement, the maximum rate of luminoldependent chmiluminescence, which partly represents O2‐H2O2‐.NO interactions, was increased only in the treated group. When other blood markers of oxidative stress were compared, only erythrocyte catalase activity was decreased in both PD patient series by 33 and 39%, respectively (p < 0.05), whereas plasma antioxidant capacity and erythrocyte superoxide dismutase activity levels were decreased only in treated PD patients. This study suggests that neurophils express a primary alteration of ·NO release in PD patients, whereas H2O2 and oxidativestress parameters are more probably related to the evolution of PD or to effects of treatment with L‐dopa.