NRG4 and metabolic syndrome: For example, decreased Nrg4 levels were associated with nonalcoholic fatty liver disease in obese children17 and were involved in the development of metabolic syndrome in newly diagnosed T2DM patients.18 Of note, Nrg4 activates autophagy to alleviate high fat diet-induced hepatic steatosis and PA-induced lipid accumulation in hepatocytes.7