A binding assay to identify the target of Nrg4 showed that Nrg4 specifically binds to the liver and improves diet-induced fatty liver disease by attenuating the hepatic lipogenic pathway [82], suggesting that circulating Nrg4 from adipose tissue ameliorates the severity of fatty liver and insulin resistance by modulating hepatic lipogenesis. Here, NRG4 is linked to fatty liver disease.