Measurement and characterization of superoxide generation from xanthine dehydrogenase: a redox-regulated pathway of radical generation in ischemic tissues.

ABSTRACT: The enzyme xanthine oxidoreductase (XOR) is an important source of oxygen free radicals and related postischemic injury. Xanthine dehydrogenase (XDH), the major form of XOR in tissues, can be converted to xanthine oxidase (XO) by oxidation of sulfhydryl residues or by proteolysis. The conversion of XDH to XO has been assumed to be required for radical generation and tissue injury. It is also possible that XDH could generate significant quantities of superoxide, •O₂⁻, for cellular signaling or injury; however, this possibility and its potential ramifications have not been previously considered. To unambiguously determine if XDH can be a significant source of •O₂⁻, experiments were performed to measure and characterize •O²⁻ generation using XDH from chicken liver that is locked in the dehydr

SUBMITTER: Lee MC 

PROVIDER: S-EPMC4204892 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature