Barley sprouts as a modulator of the gut microbiota, influencing glucose and lipid metabolism in ovariectomized female rats fed a high-fat diet

BACKGROUND/OBJECTIVES: This study examined the effects of barley sprout supplementation on glucose and lipid metabolism, and on the changes in the gut microbiota in high-fat-fed ovariectomized (OVX) rats. MATERIALS/METHODS: Female Sprague-Dawley rats aged 8 weeks (14 with an ovariectomy and 12 without) were assigned to one of 4 experimental groups: Sham-operated control group fed a high-fat diet (Sham-C; n = 6), Sham-operated group fed a high-fat diet with 2% barley sprout supplementation (Sham-B; n = 6), OVX control group fed a high-fat diet (OVX-C; n = 7), and OVX group fed a high-fat diet with 2% barley sprout supplementation (OVX-B; n = 7). RESULTS: After diet administration for 7 weeks, the OVX-B group showed lower serum fasting glucose and total cholesterol levels than the OVX-C group. Taxonomy analysis revealed significantly lower abundance of the gut microbial families Clostiridiaceae and species Enterococcus hirae and higher abundance levels of gut microbial species Clostridium saudiense in the OVX-B group than in the OVX-C group. The Principal Coordinates Analysis plot for the β-diversity assessment showed that the OVX-C group had a different gut microbiota structure than the Sham-C group. The OVX-B group formed a different microbiota structure from that of the OVX-C group, while the distribution of the OVX-B group overlapped with the regions of the Sham-C and Sham-B groups; its centroid shifted toward the Sham-B group. CONCLUSION: Barley sprout supplementation might improve glucose and lipid metabolism by modulating the gut microbiota in OVX female rats fed a high-fat diet.