Interaction of barley β-glucan and tea polyphenols on glucose metabolism in streptozotocin-induced diabetic rats.

UNLABELLED: Soluble dietary fiber and antioxidants have received much attention as most important components of functional foods. However, few data are available on the effects of the combination of tea polyphenols (TP) and β-glucan (BG) on blood glucose in a diabetic rat. The effects of administration of barley BG and TP or their combination (TP + BG) on blood glucose, lipid profiles, and antioxidant parameters on streptozotocin-induced diabetic rats were investigated. Significant improvements on the blood glucose level, serum lipid parameters (decreases in triglyceride, total cholesterol, LDL-C, and increase in HDL-C), lipid peroxidation (decrease in malondiadehyde content), and serum antioxidant status (increases in superoxide dismutase, glutathione peroxidase, and total antioxidant capacity) resulted in diabetic rats after administering TP + BG. This study, therefore, demonstrated that the intake of TP + BG has beneficial effects on glucose tolerance, lipid metabolism, and serum antioxidant status. It also revealed that TP + BG is better than TP or BG alone in improving glucose metabolism and antioxidant status in diabetic rats. Practically, the present study suggested that polyphenols-rich cereal foods are help for type 2 diabetes. PRACTICAL APPLICATION: Although TP or BG was definitely helpful in the treatment and management of diabetes mellitus, synthetic anti-hyperglycemic effects were found between TP and BG. The fortification of a BG-rich cereal diet with TP could be used as a strategy to maintain health of diabetic subjects.