FAS and obesity disorder: Recently, we have demonstrated that baicalin protected against the development of hepatic steatosis and obesity in rats induced by a long-term HFD and its protective effect is mainly associated AMPK activation and suppression of hepatic fatty acid synthase (FAS) and sterol regulatory element binding protein 1c (SREPB-1c) gene expression [11], [38], however, the underlying mechanism for AMPK activation is unknown.