Effect of stabilized rice bran-added high sucrose diet on glucose control in C57BL/6 mice

Abstract

Purpose: Rice bran is a byproduct of the hulling of rice and contains a variety of bioactive components. Various studies have reported on the antioxidative, anticancer, immune-enhancing, and hypocholesterolemic effects of rice bran. However, few studies about the physiological activity of stabilized rice bran supplement on dietary intake of sugars is limited. The aim of this study was to investigate the effect of stabilized rice bran supplement on blood glucose in C57BL/6 mice fed a high sucrose diet. Methods: Animals were randomly divided into three groups respectively, and were fed a normal diet (ND group), a high sucrose diet (HSD group) or a high sucrose diet containing 20% stabilized rice bran (HSD-SRB group) for 12 weeks. Results: In the oral glucose tolerance test (OGTT), after seven weeks of feeding on the experimental diets, a significantly lower result was observed for HSD-SRB than for HSD at 30 and 60 minutes after oral administration in glucose solution (2 g/kg body weight). The incremental area under the curve (IAUC) of HSD-SRB was significantly lower than that of HSD. After 12 weeks, fasting blood glucose level of HSD-SRB was significantly lower than that of HSD. No significant difference in the serum insulin level was observed between HSD and HSD-SRB. However, HOMA-IR was significantly decreased in HSD-SRB compared to HSD. In addition, HOMA β-cell was significantly increased in HSD-SRB compared to HSD. Triglyceride in liver of HSD-SRB was significantly lower than that of HSD. Conclusion: Feeding diets containing 20% rice bran improved insulin resistance and insulin secretion by decreasing triglyceride in liver. Thus, rice bran has a positive effect on glycemic control. In addition, the results are expected to be utilized as a basis for human study and development of food products with added rice bran.KEY WORDS: rice bran, high sucrose diet, insulin resistance, blood glucose.