MAP2K1 and Hepatic fibrosis: Another study observed that feeding mice with GCDCA (0.3%, w/w) and CA (0.1%, w/w) at the same time could lead to hepatic fibrosis, but in the subsequent in vitro study, the authors intervened with CDCA and concluded that bile acids activated hepatic stellate cells through EGFR and MEK 1/2 signaling pathways [23].