SELEGILINE AND LYMPHOCYTE SUPEROXIDE-DISMUTASE ACTIVITIES IN PARKINSONS-DISEASE

Superoxide dismutases (SODs) are metalloenzymes that detoxify superoxi de radicals, and occur in cytosolic (Cu,Zn-SOD) and mitochondrial (Mn- SOD) forms in multiple tissues, including brain. A neuroprotective eff ect against oxide stressor exposures may be provided by SOD, although excessive enzyme activity can produce cell injury by formation of hydr oxyl radical from hydrogen peroxide. We measured Cu,Zn-SOD and Mn-SOD activities in peripheral lymphocytes of 43 newly diagnosed idiopathic Parkinson's disease (PD) cases and 62 age- and sex-matched controls fr ee of neurodegenerative disorders. Significant excesses of both SOD fo rms were found among PD cases compared with controls; however, the exc esses were found exclusively among FD patients treated with the monoam ine oxidase inhibitor selegiline (L-deprenyl). Enzyme-linked immunosor bent assays (ELISAs) confirmed that the activity excesses were due to increased protein rather than more highly reactive enzymes in lymphocy tes of PD cases. Our findings clearly indicate the importance of seleg iline on measured Cu,Zn-SOD and Mn-SOD activity in peripheral lymphocy tes. Characterizing a possible therapeutic value of SOD will require l ongitudinal assessments of SOD in relation to PD progerssion.