GHRL and fatty liver disease: Studies had pointed out that high expression of Ghrelin could activate the hepatic mTOR/S6 signaling pathway in both in vivo and in vitro experiments, regulate the expression and rhythmicity of hepatic circadian locomotor output cycles kaput ear dichroism (Clock) and coding cycle Protein 2 (Per 2), restore circadian rhythm disturbance, improve hepatic steatosis, and reduce chronic inflammation (Wang et al., 2018a).