Alginate oligosaccharides improve high-fat induced hepatic steatosis via PGC-1α-mediated lipophagy and fatty acid β-oxidation pathway

This study explored the lipid-lowering effect and intervention mechanism of alginate oligosaccharides (AOS) on non-alcoholic fatty liver disease (NAFLD). Results showed that both unsaturated (UAOS) and saturated (SAOS) AOS improved the hepatic steatosis of NAFLD mice fed a high-fat diet (HFD). AOS promoted lipid catabolism in vivo and in vitro by activating the lipophagy and free fatty acid (FFA) 8 -oxidation pathways. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 alpha) represented the up-stream target of the FFA 8 -oxidation pathway and upregulated both in in vivo and in vitro, suggesting it might be the AOS intervention target. By activating or inhibiting PGC-1 alpha, AOS modulated the PGC-1 alpha activity to reduce hepatic lipid accumulation. Therefore, the results indicated that AOS exhibited a lipid-lowering effect via the PGC-1 alpha-mediated lipophagy-FFA 8 -oxidation transduction signal axis. These findings provided insight into using food-derived ingredients to intervene and treat chronic diseases involving lipid metabolism disorders.