STAT3 and fatty liver disease: Further targeted IL-22-ApoA1 gene delivery in the liver significantly alleviated hepatitis steatosis and improved metabolic syndromes such as insulin resistance by modulating the STAT3/ERK1/2 and nuclear factor erythroid 2-related factor 2 (Nrf2)/superoxide dismutase 1 (SOD1) signaling, and lipid metabolic gene expression in an HFD-fed mouse model [25].