Vitamin E radical reaction with antioxidants in rat liver membranes

The Japanese herbal medicine Sho-saiko-to-go-keishi-ka-shakuyaku-to (TJ-960) has been demonstrated to have an antioxidant action by quenching free radicals. The effects of TJ-960 on the tocopheroxy radicals generated by an arachidonic acid and lipoxygenase oxidation system were compared with those of the ascorbate and glutathione in vitamin E-enriched rat liver microsomes and submitochondrial membrane particles (SMP). Using electron spin resonance spectrometry, the disappearance of the tocopheroxy radicals after addition of glutathione and ascorbate was detected in microsomes and SMP, with ascorbate displaying a more potent action than glutathione. Addition of TJ-960 demonstrated a similar effect on the tocopheroxy radicals in microsomes and SMP. In the presence of TJ-960, ascorbate, and glutathione, the loss of vitamin E in the vitamin E-enriched microsomes of rat liver undergoing oxidation was slowed down. In this paper, we introduced TJ-960 as another replenisher of vitamin E in membrane, increasing the membrane's resistance against oxidative damage.