FABP4 and fatty liver disease: Moreover, IL-1β KO mice being high-fat fed (HFF) had lower mRNA levels of proinflammatory factors, increased expression of the adipogenic genes (Pparγ, Cebpα, Cebpβ, Fabp4) in adipose tissue and less hepatic steatosis compared with wild-type HFF mice, which suggests that IL-1β could impair fat storage and promote ectopic fat accumulation by limiting adipose tissue expandability (37).