FASN and colitis: Recently, a number of mouse models have been generated to focus on the interaction of metabolism and intestinal barrier function [2–5], for instance, AMPK improves gut epithelial differentiation and barrier function via regulating caudal-type homeobox transcription factor 2 (CDX2) expression, and fatty acid synthase (FASN) modulates intestinal barrier function through palmitoylation of mucin 2, while sirt5 desuccinylates and activates pyruvate kinase M2 (PKM2) to block macrophage IL-1beta production and to prevent DSS-induced colitis in mice.