Experimental design, weight curves and disease activity index.

<p>(A) One cycle of DSS comprises 7 days of DSS followed by a recovery period of 14 days with normal drinking water. The study set-up consists of 6 different groups (n = 10 for each group with exception of the control group (n = 7) and 3-cycles group (n = 9). Acute colitis mice (n = 10) received 7 days of DSS without a recovery period prior to sacrifice and/or scanning. In a second group (n = 10) colitis was induced by DSS for 7 days followed by a recovery period of two weeks with normal drinking water, and this was defined as one cycle of DSS. In a third and fourth group, the DSS cycle was repeated twice (n = 10) or three times (n = 10). A fifth group (n = 10) received two cycles of DSS followed by an additional recovery period of three weeks with normal drinking water. Control mice (n = 7) received normal drinking water throughout. All mice were 6-weeks old at time of start of the 9-weeks study period and in this way age-matched at the time of sacrifice and scanning (15-weeks old). (B) Weight curves of control mice, acute, 2-, and 3-cycles mice. Data are expressed as medians with interquartile range (IQR). (C) The disease activity index (DAI) was determined at the end of the 9-weeks study period, based on body weight loss (one point for each 5% loss of weight), stool consistency (0, normal; 2, formed but very soft; 4, liquid) and presence of gross blood in the stools (0, none; 1, present). Data are expressed as medians with IQR. Mann-Whitney U testing (*p<0.05, **p≤0.01, ***p≤0.001).