Microencapsulated rice bran alleviates hyperlipidemia induced by high-fat diet via regulating lipid metabolism and gut microbiota

Hyperlipidemia has been suggested to be associated with dysregulation of lipid metabolism and gut microbiota. The present study prepared microencapsulated rice bran (MRB) with high stability based on in situ rice bran oil embedding and investigated the effects of MRB on lipid metabolism and gut microbiota in hyperlipidemic mice induced by high-fat diet (HFD). Results showed that compared to HFD fed mice, lipid levels in serum and hepatic lipid accumulation were reduced in mice fed with MRB, which was potentially associated with the fact that MRB decreased the expression of genes related to lipogenesis (Srebp1c, Acc, Hmgcr, and Fas) and increased the expression of genes related to lipid catabolism (Hsl, Atgl) and oxidation (Acox, Cpt1, Ucp1) (p < 0.05). In gut, MRB supplementation significantly elevated the abundance of beneficial bacteria, such as Dubosiella and Faecalibaculum. In addition, significant increase in short-chain fatty acid was observed in mice from MRB groups when compared to HFD groups (p < 0.05). Overall, this study suggested that MRB could alleviate the hyperlipidemia induced by HFD, which was related to the alteration of lipid metabolism and gut microbiota.