Lipid Peroxidation Induced by the Reaction of Cytochrome c with Hydrogen Peroxide

Abstract

Lipid peroxidation induced by the reaction of cytochrome c with <TEX>$H_2O_2$</TEX> was investigated. When linoleic acid micelles or phosphatidyl choline liposomes were incubated with cytochrome c and <TEX>$H_2O_2$</TEX>, lipid peroxidation was increased in cytochrome c and <TEX>$H_2O_2$</TEX> concentrations-dependent manner. Radical scavengers, azide, formate and ethanol prevented lipid peroxidation induced by the cytochrome c/<TEX>$H_2O_2$</TEX> system. Iron specific chelator, desferoxamine also prevented the cytochrome c/<TEX>$H_2O_2$</TEX> system-mediated lipid peroxidation. These results suggest that lipid peroxidation may be induced by the cytochrome c/<TEX>$H_2O_2$</TEX> system via the generation of free radicals. Carnosine, homocarnosine and anserine are present in the muscle and brain of many animals and human. Previous studies show that these compounds have an antioxidant function. In the present study, carnosine, homocarnosine and anserine significantly prevented the cytochrome c/<TEX>$H_2O_2$</TEX> system-mediated lipid peroxidation. Carnosine and related compounds also inhibited the free radical-generating activity of cytochrome c. The results suggest that carnosine, homocarnosine and anserine may prevent lipid peroxidation induced by the cytochrome c/<TEX>$H_2O_2$</TEX> system through a free radical scavenging.