In colonic epithelium of UC patients, PPARγ expression was down-regulated (Dubuquoy et al., 2003); PPARγ agonist rosiglitazone could treat moderate UC (Lewis et al., 2008; Pedersen and Brynskov, 2010); 5-aminosalicylic acid (5-ASA), a traditional UC therapeutic drug, ameliorated the symptoms of wild-type colitis mice, but was ineffective in PPARγ+/- heterozygous mice (Rousseaux et al., 2005). Here, PPARG is linked to colitis.