Insoluble yeast β-glucan attenuates high-fat diet-induced obesity by regulating gut microbiota and its metabolites.

Emerging evidence suggests that insoluble dietary fiber prevents obesity by regulating gut dysbiosis. However, whether insoluble yeast β-glucan (IYG) has an anti-obesity effect is still unclear. Here, the impact and potential mechanism of long-term IYG supplementation on high-fat diet (HFD)-induced obesity were investigated. After 24 weeks of long-term supplementation, IYG ameliorated weight gain, dyslipidemia, systemic inflammation, glucose intolerance and insulin resistance in HFD-fed rats. In addition, HFD-induced gut dysbiosis and changed levels of short-chain fatty acids and lipopolysaccharide were restored by IYG. Meanwhile, HFD-induced downregulations of tight junction proteins and Mucin 2 as well as elevated gut permeability were recovered by IYG. IYG also mitigated HFD-induced colonic inflammation and oxidative stress. Moreover, antibiotic treatment abrogated the protective effect of IYG on obesity, indicating the important role of gut microbiota in IYG's effect. This study demonstrated that IYG, as a potential prebiotic, exhibited a protective effect on HFD-induced obesity.