Inhibitory Effect of Selenite and Se-enriched Kaiware Radish Sprouts on Formation of Aberrant Crypt Foci in Colon of Mice Administered 1,2-Dimethylhydrazine

Abstract

To evaluate anti-carcinogenic activity of selenite and selenium (Se)-rich kaiware daikon sprouts (Se sprouts), their inhibitory effects on formation of aberrant crypt foci (ACF) were evaluated in colon of mice administered 1,2- dimethylhydrazine (DMH). Male 4-week A/J mice were divided into 7 dietary groups and fed a casein-based low Se basal diet (Se content: 0.03 μg/g) or the basal diet supplemented with selenite, Se-sprouts (Se content: 135 μg/g dry basis) or selenite + control sprouts (Se content: < 0.01 μg/g dry basis) at a level of 0.05 or 0.10 μg Se/g for 9 weeks. After 1 week of feeding, mice in all dietary groups were given six subcutaneous injections, separated by 1 week, of DMH (20 mg/kg body weight). Several number of mice fed the basal diet were injected with saline. Injection with DMH caused formation of a lot of number of ACF in colon of the mice fed the basal diet. Dietary supplementation with selenite at a level of 0.05 μg Se/g significantly inhibited the formation of ACF. However, this inhibitory effect of selenite was not observed in mice supplemented with selenite at a level of 0.10 μg Se/g. On the other hand, significant inhibitory effect of Se sprouts on the ACF formation was not observed in mice supplemented with Se sprouts at a level of 0.05 μg Se/g but observed in those at a level of 0.10 μg Se/g. Supplementation with control sprouts did not effect on the ACF formation.