NR1D1 and fatty liver disease: Gene therapy using AAV8-mediated NR1D1 overexpression or ApoA5 restoration significantly attenuated hepatic steatosis in ApoA5-/- hamsters with or without affecting plasma lipid profiling, respectively, whereas activation of adipose tissue by exposure to cold or CL316243 completely ameliorated hyperlipidemia and hepatic steatosis due to ApoA5 deficiency.