DETECTION OF DOPAMINE - DNA ADDUCTS - POTENTIAL ROLE IN PARKINSONS-DISEASE

Oxidation of catecholamines may lead to the formation of o-semiquinone s and o-quinones in catecholaminergic brain tissues, and these reactiv e molecules may form DNA or protein adducts. In this study, cultured c ells were treated with dopamine (DA) for 24 h and P-32-postlabeling wa s used to detect DA-DNA adducts. In HL-60 cells, 250 muM DA induced 8. 5 DNA adducts/10(8) nucleotides; adduct formation was dose-dependent u p to 500 muM DA. Addition of H2O2 increased the relative adduct levels 7- to 13-fold, but no adducts were detected when DA and ascorbic acid were added simultaneously. In human glioblastoma cell lines U87, U251 , SF-763 and SF-767, 1000 muM DA produced 0.98-2.31 adducts/10(8) nucl eotides. These results suggest that the formation of DNA adducts by DA may contribute to the development of certain neurodegenerative diseas es such as Parkinson's disease.