Figure 2: Antibiotics effect on DSS-induced colitis.

(a) Mice were treated with vancomycin (Van), neomycin (Neo), penicillin (Pen), streptomycin (Stp), chloramphenicol (CAM) and metronidazole (Met) for 3 weeks before DSS challenge for 5 days. Body weight was measured by day 8 after initiation of DSS challenge and given as percentage to the body weight of mice challenged with DSS without antibiotics. The data are represented as mean±s.e.m. N=6–8, *P<0.05 (two-tailed Student’s t-test). (b) Intestinal permeability was measured by FITC–dextran levels in the serum from control, colitogenic mice on day 5 of DSS challenge, and 3 weeks of antibiotic pretreated mice. N=5, *P<0.05 (ANOVA, Bonferroni’s multiple comparison test). (c) Relative change in body weight of WT and ST mice treated with 0.5 g l⁻¹ Van for 7 days and 3% DSS for 5 days; control mice received DSS without Van. (d) Relative change in body weight of WT and ST mice treated with 1 g l⁻¹ Stp for 8 days and 3% DSS for 5 days. (e) Colon length was determined at the end point of DSS treatment. In (c–e) the data are represented as mean±s.e.m. from two independent experiments, N=6-8, *P<0.05 (ANOVA, Bonferroni’s multiple comparison test). (f) 16S rRNA pyrosequencing analysis of faecal microbial taxa families in untreated WT mice, in Van, Stp-treated WT mice and DSS-challenged WT mice (WT–DSS). The data are represented as the percentage of total identified sequences obtained from a pool of eight mice per group.