MUC5AC and colitis: Previous studies reported altered expression or loss of TJ proteins occludin and ZO-1 and reduced mucin expression in colitis patients and in mouse models of intestinal inflammation (Kucharzik et al., 2001; Poritz et al., 2007; Turner, 2009; Poritz et al., 2011; Das et al., 2012; Li et al., 2014; Nighot et al., 2015), which the present study confirmed.