Polysaccharide from Angelica sinensis with medicinal and edible purposes ameliorated NAFLD by the bile acids mediated activation of FXR

Liver and gut communicates with each other through metabolites and the gut-liver axis plays a crucial role in lipid metabolism. Enterohepatic bile acid circulation is an important constitution of gut-liver axis. Farnesoid X receptor (FXR)，a bile acid mediated nuclear receptor, is promising therapeutic targets for the non-alcoholic fatty liver disease (NAFLD). More and more studies have confirmed the effects of Angelica sinensis polysaccharide (ASP) on liver protection and lipid regulation. However, little attention has been paid to the role of ASP on the gut-liver axis, which is crucial to clarify how ASP play a role in liver protection after oral administration. In vivo and in vitro models of NAFLD were established to examine the effect of ASP on hepatic fat accumulation. Our results showed that ASP could alleviate liver fat accumulation. However, the expression of FXR was not changed when ASP directly acting on hepatocytes, while ASP could change the expression of FXR in liver and intestine of mice after oral administration. In addition, our results showed that ASP could promote the excretion of bile acids, thereby increasing cholesterol metabolism. Our research provided a new concept for the mechanism of ASP regulating liver lipid metabolism and exerting liver protection.