This ROS clearance upon MDP stimulation depends on the mitophagy-mediated elimination of damaged mitochondria through ATG16L1 and NOD2, and interestingly, these genetic loci have been widely implicated as IBD- susceptibility loci.55,56 The role of MDP in colitis was further strengthened by a recent report highlighting that the Gram-positive bacteria promote colitis in DSS model via upregulation of MDP-NOD2 pathway and paeoniflorin, a selective MDP inhibitor, is able to decrease the infiltration of these bacteria in intestine and alleviate mice colitis by inhibiting the MDP-NOD2 pathway.57 Here, NOD2 is linked to colitis.