Hence, long-term treatment of mice with nicotinamide mononucleotide increased the number of goblet cells and promoted mucus secretion (Huang et al., 2021), whereas conversely, the number of goblet cells and mucin were reduced in rats suffering from colitis (Pélissier et al., 2006) or in HFD-fed mice (Huang et al., 2021). This evidence concerns the gene MUC5AC and colitis.