FOXO1 and fatty liver disease: Using the generated myeloid Foxo1 and YAP double-KO (Foxo1/YAPM-DKO) mice, we found that Foxo1M-KO decreased lipid accumulation, whereas Foxo1/YAPM-DKO resulted in increased hepatic steatosis after 24 weeks of HFD feeding (Fig. 8a, b).