Lipid peroxidation of erythrocyte membrane induced by lipoamide dehydrogenase in the presence of ADP-Fe3+.
Lipid peroxidation of rat erythrocyte membranes was induced by lipoamide dehydrogenase (LADH) (EC 1.8.1.4) in the presence of ADP-Fe3+. Superoxide dismutase (SOD) (EC 1.15.1.1) strongly inhibited the peroxidation reaction but catalase did not. Hydroxyl radical scavengers, mannitol and dimethylsulfoxide did not inhibit the lipid peroxidation. These results indicated that the lipid peroxidation was a superoxide (O2-)-dependent reaction, but the hydroxyl radical was not involved. ADP-Fe3+, in the presence of LADH, was reduced more rapidly under aerobic than anaerobic conditions and SOD under aerobic conditions strongly inhibited the iron reduction, indicating that O2- plays a predominant role in iron reduction. Hydrogen peroxide enhanced O2- generation by LADH, but the peroxidation reaction was not affected. In the presence of lipoamide, lipid peroxidation was also induced but the reactions were not inhibited by SOD. Evidently, the lipid peroxidation induced in the presence of lipoamide was O2(-)-independent. Dihydrolipoamide may be involved in the peroxidation reaction.
Miura
T
T
Hokkaido Institute of Pharmaceutical Sciences, Otaru, Japan.
Muraoka
S
S
Ogiso
T
T
D000244:Adenosine Diphosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D000818:Animals; D008058:Dihydrolipoamide Dehydrogenase / Q000494:pharmacology*; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism*; D016166:Free Radical Scavengers; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007502:Iron Chelating Agents; D015227:Lipid Peroxidation / Q000187:drug effects*; D051381:Rats; D013482:Superoxide Dismutase / Q000494:pharmacology; D008063:Thioctic Acid / Q000031:analogs & derivatives / Q000494:pharmacology
D016166:Free Radical Scavengers; D007502:Iron Chelating Agents; C029936:adenosine diphosphate-ferric chelate; D000244:Adenosine Diphosphate; D008063:Thioctic Acid; C013091:lipoamide; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase; D008058:Dihydrolipoamide Dehydrogenase