Polysaccharide from Caulerpa lentillifera alleviates hyperlipidaemia through altering bile acid metabolism mediated by gut microbiota

Polysaccharide from Caulerpa lentillifera (CLP) offers preventative health benefits, but its efficacy against hyperlipidaemia and underlying mechanisms still elusive. This investigation assessed CLP's potential to mitigate high-fat diet (HFD)-induced hyperlipidaemia via the gut microbiota-bile acid (BA) axis. In hyperlipidaemic mice, 8 weeks of CLP treatment improved body weight, lipid profiles, and hepatic function, correlating with shifts in BA concentrations. Additionally, CLP not only repaired HFD-induced gut dysbiosis by increasing SCFA-producing bacteria but also positively modulated gut metabolites, including acetic and butyric acids. Spearman's correlation analysis illustrated strong associations between the altered microbes, metabolites, and the expression of genes involved in BA metabolism. Remarkably, CLP significantly influenced BA levels related to hyperlipidaemia, partly by augmenting the population of Parabacteroides and associated butyric acid level. These results indicate that CLP may serve as a functional food to guard against dyslipidaemia through impacting specific gut microbes and metabolites such as Parabacteroides and butyrate, and thus presenting promising therapeutic prospects for diseases associated with BA metabolism.