Abstract: 【Objective】 The study was aimed to construct a mouse inflammatory bowel disease (IBD) model by stimulating with dextran sulfate sodium (DSS) or lipopolysaccharide (LPS), providing an efficient and economical model reference for IBD research, and providing reliable methodological support for the screening and efficacy evaluation of IBD anti-inflammatory drugs. 【Method】 C57BL/6 male mice were chosen and exposed to different concentrations of DSS (3%, 4% and 5%) for 7 d or LPS (5, 10 and 20 mg/kg) for 4 h in the current study.The model was evaluated by measuring colon length, observing intestinal morphology and structure with HE staining, and detecting mRNA expression of intestinal inflammatory factors by Real-time quantitative PCR. 【Result】 DSS could decrease the colon length of mice, led to pathological bleeding, atrophy of glands and disordered structure in colon.Moreover, DSS significantly induced inflammatory cell infiltration and the mRNA expression of the inflammatory cytokines interleukin-1β (IL-1β), IL-6, IL-10 and tumor necrosis factor-α (TNF-α) in the colon of mice, which implied that 4% DSS could establish the IBD efficiently.Meanwhile, LPS could cause mesenteric hemorrhage, intestinal swelling and congestion of mice.Moreover, LPS could decrease the villus height and increased the crypt depth in the intestine.In addition, LPS could also upregulate mRNA levels of intestinal inflammatory cytokines IL-10 and IL-1β, downregulate IL-6 mRNA level and elevate TNF-α mRNA level in the duodenum and ileum, and reduce TNF-α mRNA level in the jejunum.It was found that the most significant effect of intestinal damage was 5 mg/kg LPS treatment. 【Conclusion】 4% DSS or 5 mg/kg LPS treatment were the optimal concentrations to establish IBD model in C57BL/6 mice.Intestinal pathomorphological changes, intestinal inflammatory cell infiltration and inflammatory factors disorder such as the mRNA expression of IL-1β, IL-6, IL-10 and TNF-α were important indicators to evaluate the models of IBD.

Key words: dextran sodium sulfate (DSS); lipopolysaccharide (LPS); inflammatory bowel disease; intestinal inflammation; C57BL/6 mice