Establishment of Two Murine Models of Ulcerative Colitis and Comparison of the Mechanism of Colitis-related Inflammatory Reactions

  Objective  To establish two murine models of ulcerative colitis (UC) and explore the mechanism of colitits-related inflammatory reactions.

  Methods  Totally 12 C57BL mice were randomly divided into two groups:dextransulfatesodium (DSS) model group (n=8, allowed to drink 3% DSS for 5 days) and DSS control group (n=4, allowed to drink water for 5 days). In addition, 8 BALB/C mice were randomly divided into oxazolone (OXZ) model group(n=4, mice were skin-sensitized with 3% OXZ 0.2 ml in 100% ethanol for 2 days followed by intrarectal administration of 0.8% OXZ 0.15 ml in 50% ethanol 5 days later) and OXZ control group(n=4, mice were skin-sensitized with 100% ethanol for 2 days followed by intrarectal administration of 50% ethanol 0.15 ml 5 days later). The disease activity index (DAI), tissular general score, and histological score were calculated. The levels of myeloperoxidase (MPO), interleukin 4 (IL-4), interferon-γ (INF-γ), tumor necrosis factor-α(TNF-α), and nuclear factor-Kappa B (NF-κB) in the colon tissue were determined.

  Results  DAI, tissular general score, and histological score were significantly different in either DSS or OXZ model group when compared with their control groups. MPO, TNF-α, and NF-κB significantly increased in DSS and OXZ model groups. In addition, INF-γ significantly increased in DSS model group and IL-4 significantly increased in OXZ model group.

  Conclusions  Both DSS and OXZ can induce ulcerative colitis in mice. OXZ-induced murine colitis is highly associated with T helper cell type 2 (Th2), which is more similar to human UC.