Miura T, Muraoka S, Ogiso T
Hokkaido Institute of Pharmaceutical Sciences, Otaru, Japan.
Pharmacol Toxicol. 1992 Oct;71(4):297-301. doi: 10.1111/j.1600-0773.1992.tb00987.x.
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.
