Figure 3.

Summary of the putative roles of gut-derived secretory factors in the pathogenesis of NAFLD/NASH on the basis of the gut-liver axis. Resistin like molecule β (RELMβ) is secreted by goblet cells and delivered from the intestinal lumen into the lamina propria through a disrupted epithelial barrier, and then translocates into the portal vein and reaches the liver. Glucagon-like peptide-1 (GLP-1), glucagon-like peptide-2 (GLP-2), fibroblast growth factor (FGF) 19 and neurotensin are released from enteroendocrine cells into the lamina propria and reach the liver through the portal vein. Increased intestinal secretion and circulating RELMβ and neurotensin levels and decreases in those of GLP-1, GLP-2 and FGF19 could be involved in the pathogenesis of non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) in various ways.