Since the concentration of 5-ASA used for the treatment of rat colitis via the rectal route was 20–30 mM [29] and DpS was detected in the cecum at half the concentration of 5-ASA upon oral administration of As-DpS-AS, 20 mM of 5-ASA, and/or 10 mM of DpS were administered via the rectal route. This evidence concerns the gene PDSS1 and colitis.