Oxidative stress indicators are elevated in de novo Parkinson's disease patients

In order to determine the baseline state of oxidative stress indices in drug-free patients with Parkinson's disease (PD), we analyzed cerebrospinal fluid (CSF) and peripheral blood samples of 34 subjects in disease stages I-III, according to the Hoehn & Yahr scale, compared with controls. The results showed a highly significant increase in malondialdehyde content in CSF (p < 0.001) in the patients with PD. We also found significant differences in peripheral blood parameters between the two groups: malondialdehyde content was increased in patients with PD (p < 0.05), as was the activity of antioxidative defense enzymes, glutathione reductase, Cu, and Zn-superoxide-dismutase (p < 0.05). The production of a highly reactive oxygen species--superoxide radical (p < 0.05) was also increased. These findings indicated an important role of oxidative stress in PD evolution and progress. The increased levels of reactive oxidative species (malondialdehyde content and superoxide radical production) in peripheral blood, and excessive activity of protective enzymatic systems (glutathione reductase Cu, and Zn-superoxide-dismutase) could indicate an additional systemic reaction related to a chronic oxidative stress state in the brain.