Effect of a High-fat Diet with Barley β-glucan on Glucose Tolerance and Abdominal Fat-liver Lipid Accumulation in Mice

Abstract

Objective: Barley has been reported to possess several physiological effects. However its dose-dependent effects when fortified with β-glucan isolate have not yet been elucidated. The purpose of this study was to investigate the effect of a high-fat diet with barley β-glucan on glucose tolerance and abdominal fat-liver lipid accumulation in mice.
Methods: Thirty-two 6-week-old mice were randomly divided into 4 groups of 8 and fed high-fat experimental diets. The percentage content of β-glucan in the control (C) group, whole grain barley (B) group, barley fortified with β-glucan isolate (B + G) group, and β-glucan isolate (G) group were 0.0, 1.2, 3.1, and 5.0%, respectively. The experimental diets and tap water were provided ad libitum for 12 weeks. Glucose tolerance tests were performed and then liver lipid contents, serum insulin, and leptin concentrations were measured. The average size of abdominal adipocytes was also measured using a Coulter counter.
Results: Serum insulin concentrations and area under the curve of blood glucose in the control group were significantly lower compared with all barley groups, and significant dose-dependency with β-glucan content was also observed. Serum leptin concentrations, average size of adipocytes, abdominal fat weight, and liver lipid accumulation were all reduced by β-glucan dose-dependently.
Conclusions: These results suggested that barley β-glucan improved glucose tolerance and suppressed abdominal fat and liver lipid accumulation dose-dependently in mice. Similar results in human trials are anticipated.