Dietary sesame seeds elevate alpha-tocopherol concentration in rat brain

We have previously reported that dietary sesame lignan elevates alpha-tocopherol concentration and decreases lipid peroxidation in tissues and serum of rats fed alpha-tocopherol. In this study, the effect of dietary sesame seeds on alpha-tocopherol concentration and lipid peroxidation in rat brain was examined. In experiment 1, male Wistar rats (4 wk old) were fed a vitamin E-free diet, or a diet containing alpha-tocopherol with or without sesame seeds for 1, 4 and 8 wk. The dietary sesame seeds elevated the alpha-tocopherol and lowered the thiobarbituric acid-reactive substance (TBARS) concentrations in the brain of the rats fed alpha-tocopherol for 4 and 8 wk. The dietary sesame seeds maintained the high alpha-tocopherol concentration in the brain during the experimental period, while the concentration of the rats fed alpha-tocopherol without sesame seeds was lowered after 8 wk. Then, the alpha-tocopherol concentration in various regions of the brain of rats fed a basal level of alpha-tocopherol with sesame seeds was compared with that of rats fed an excess amount of alpha-tocopherol in experiment 2. The alpha-tocopherol concentration in the cerebrum, cerebellum, brain stem and hippocampus of the rats fed 50 mg alpha-tocopherol/kg with sesame seeds was higher than those of the rats fed 500 mg alpha-tocopherol/kg without sesame seeds. These results suggest that the dietary sesame seeds are more useful than the intake of an excess amount of alpha-tocopherol, for maintaining a high alpha-tocopherol concentration and inhibiting lipid peroxidation in the various regions of the rat brain.