Therapeutic effect of Au/CeO2@HA in ulcerative colitis. (A) Overall protocol of the animal experiment. C57BL/6 mice received water or 3% DSS-containing water for 6 consecutive days. On the day 7, 9, and 11, mice were orally administered with Au/CeO2@HA or CeO2@HA (2 mg/kg) (n = 7). (B) Relative body weights of mice receiving treatments. (C) Colon lengths and (D) photos of colon tissues with indicated treatments on day 12. (E) Hematoxylin-eosin (H&E) staining images of colon tissues. (F) Relative myeloperoxidase (MPO) activity in colon homogenates. TNF-α levels in colon homogenates (G) and serum (H) of each group. IL-6 levels in colon homogenates (I, pg/mg protein) and serum (J, pg/mL) of each group. (K) IL-1β levels in colon homogenates of each group. Data represent mean ± SD (*p<0.05, **p<0.01, and ***p<0.001).