FSTL1 and steatosis: Liver tissue H&E staining showed that the degree of steatosis and inflammation in F4MKO mice injected with AAV-FSTL1 were similar to that observed in Flox mice (Fig. 4d), which was further illustrated by the NAS scores of the liver tissue of Flox, F4MKO, and F4MKO + FSTL1 mice (Fig. 4e).