Generation of alloxan free radicals in chemical and biological systems: implication in the diabetogenic action of alloxan.
Electron spin resonance (ESR) studies that on reaction with NADPH, alloxan was reduced forming labile anion radicals giving a 7-line signal with g = 2.005. These radicals were also produced on incubation of alloxan with rat liver subcellular fractions and their production was greatly enhanced by NADPH. Alloxan effectively scavenged superoxide anion generated by a xanthine-xanthine oxidase (XOD) system in association with its reduction to these anion radicals. These radicals were also formed during incubation of alloxan with rat pancreatic beta-cells. These results suggest that the cytotoxicity of alloxan is related to the formation of alloxan anion radicals.
Nukatsuka
M
M
Faculty of Pharmaceutical Sciences, University of Tokushima, Japan.
Sakurai
H
H
Kawada
J
J
D000496:Alloxan / Q000378:metabolism; D000818:Animals; D001463:Barbiturates; D001711:Biotransformation; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D015394:Molecular Structure; D009249:NADP; D010084:Oxidation-Reduction; D051381:Rats
D001463:Barbiturates; D005609:Free Radicals; C004718:dialuric acid; D009249:NADP; D000496:Alloxan; D003577:Cytochrome P-450 Enzyme System