title: Gp91phox-containing NAD(P)H oxidase increases superoxide formation by doxorubicin and NADPH.
abstract: Doxorubicin is a highly effective antineoplastic drug associated with a dose-dependent cardiotoxicity that may result in irreversible cardiomyopathy and heart failure. Gene variants of the superoxide-generating enzyme NAD(P)H oxidase have recently been associated with this phenotype. We investigated the mechanism of this association using lucigenin-enhanced chemiluminescence, spectrophotometry, electrochemical sensor, and electron paramagnetic resonance spectroscopy. Superoxide production was measured in female wild-type and NAD(P)H oxidase-deficient (gp91phox knockout) mice. The magnitude of the increase in superoxide production on the addition of doxorubicin was much higher in hearts of wild-type mice than in enzyme-deficient mice. An increase in superoxide production was observed also on the addition of the NADPH cytochrome P450 reductase. However, doxorubicin reacted with NADPH producing superoxide even in the absence of any enzymatic activity. Taken together, gp91phox-containing NAD(P)H oxidase and NADPH cytochrome P450 reductase can enhance superoxide production caused by the chemical interaction of doxorubicin and NADPH. These findings are in agreement with the recently reported reduced cardiotoxicity following doxorubicin treatment in gp91phox knockout mice and with associations between NAD(P)H oxidase gene variants and sensitivity to doxorubicin.
authors.affiliation: Department of Pharmacology, Johannes Gutenberg University, Obere Zahlbacher Strasse 67, 55101 Mainz, Germany.
authors.forename: Shiwei
authors.initials: S
authors.lastname: Deng
authors.forename: Anke
authors.initials: A
authors.lastname: Kruger
authors.forename: Andrei L
authors.initials: AL
authors.lastname: Kleschyov
authors.forename: Leszek
authors.initials: L
authors.lastname: Kalinowski
authors.forename: Andreas
authors.initials: A
authors.lastname: Daiber
authors.forename: Leszek
authors.initials: L
authors.lastname: Wojnowski
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology*; D015870:Gene Expression; D049449:Luminescence; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism; D009249:NADP / Q000494:pharmacology*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000378:metabolism*; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D016133:Polymerase Chain Reaction; D013481:Superoxides / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D008562:Membrane Glycoproteins; D013481:Superoxides; D009249:NADP; D004317:Doxorubicin; D009251:NADPH-Ferrihemoprotein Reductase; C488842:Cybb protein, mouse; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases