Epicatechin and β-glucan from whole highland barley grain ameliorates hyperlipidemia associated with attenuating intestinal barrier dysfunction and modulating gut microbiota in high-fat-diet-fed mice

Hyperlipidemia is associated with intestinal barrier dysfunction and gut microbiota dysbiosis. Here, we aimed at investigating whether epicatechin (EC) and β-glucan (BG) from whole highland barley grain alleviated hyperlipidemia associated with ameliorating intestinal barrier dysfunction and modulating gut microbiota dysbiosis in high-fat-diet-induced mice. It was observed that EC and BG significantly improved serum lipid disorders and up-regulated expression of PPARα protein and genes. Supplementation of EC and BG attenuated intestinal barrier dysfunction via promoting goblet cells proliferation and tight junctions. Supplementation of EC and BG prevented high fat diet-induced gut microbiota dysbiosis via modulating the relative abundance of Ruminococcaceae, Lactobacillus, Desulfovibrio, Lactococcus, Allobaculum and Akkermansia, and the improving of short chain fatty acid contents. Notably, combination of EC and BG showed synergistic effect on activating PPARα expression, improving colonic physical barrier dysfunction and the relative abundance of Lactobacillus and Desulfovibrio, which may help explain the effect of whole grain highland barley on alleviating hyperlipidemia.