Membrane damage due to lipid oxidation.

The influence of free radical-mediated oxidations is amplified because it proceeds by a chain mechanism, ie, only one radical can initiate chain reaction which may propagate over and over again. It was found that the in vitro oxidations of erythrocyte membranes proceed by a chain mechanism with a long kinetic chain length. Thus, the role of chain-breaking antioxidants is quite important, since they scavenge chain-carrying radicals to break a chain reaction. In fact, it has been found experimentally that vitamin E, a lipophilic chain-breaking antioxidant present within the membranes, suppresses the oxidative damage of the membranes more efficiently than water-soluble chain-breaking antioxidants such as vitamin C, which scavenges aqueous radicals but can not scavenge chain-carrying radicals within the membranes.