Amelioration of DSS-induced ulcerative colitis in mice by Chlamydia muridarum

[Objective] To study the effect of Chlamydia muridarum on the ulcerative colitis induced by dextran sulfate sodium (DSS) in mice. [Methods] In total 15 female C57BL/6J mice were randomly divided into 3 groups: control group, DSS group, experimental group (CM+DSS group). The mice of CM+DSS group were administrated with 2×10⁵ IFU Chlamydia muridarum by gavage. After 28 days, the mice of the DSS group and CM+DSS group drank 2% DSS water for 5 days, then they were monitored for body weight and disease activity index, the colon length of all mice, and the inflammatory damage of intestine tissue. [Results] The model of ulcerative colitis induced by DSS was well established with the body weight loss of colitis mice, increased disease activity index, short colon length, and severe inflammatory reaction of colon tissue. Compared with the DSS group, CM+DSS group recovered largely, including the body weight loss, disease activity index, colon length, and colon inflammatory damage. [Conclusion] Chlamydia muridarum could ameliorate ulcerative colitis induced by DSS.