摘要AIM: To investigate the therapeutic effects of four strains of probiotics ( E. feacalis, L. acidophilus,C. butyricum and B. adolescentis) on dextran sulphate sodium (DSS)-induced experimental colitis in Balb/c mice.METHODS: Eighty Balb/c mice were randomly divided into 8 groups. Weight-loss, fecal character, fecal occult blood and hematochezia were recorded daily. Disease activity index (DAI) scores were also evaluated everyday. Length of colon was measured and histological scores were evaluated on the 13th day. Myeloperoxidase (MPO) activity was detected. Interleukin-1 (IL-1) and IL-4 expression was detected by ELISA and RT-PCR.RESULTS: The four strains of probiotics relieved the inflammatory condition of DSS-induced experimental colitis in mice. Weight loss was slowed down in all probiotics-treated mice. Even weight gain was observed by the end of probiotics treatment. The DAI and histological scores of probiotics-treated mice were lower than those of mice in the control group (1.9 ± 0.2vs 8.6 ± 0.4, P < 0.05 for E. faecalis). The length of colon of probiotics-treated mice was longer than thatof mice in the control group (10.3 ± 0.34 vs 8.65 ± 0.77,P < 0.05 for E. faecalis). The four strains of probiotics decreased the MP activity and the IL-1 expression, but increased the IL-4 expression. E. faecalis had a better effect on DSS-induced experimental colitis in mice than the other three strains.CONCLUSION: The four strains of probiotics have beneficial effects on experimental colitis in mice. E. faecalis has a better effect on DSS-induced experimental colitis in mice than the other three strains. Supplement of probiotics provides a new therapy for UC.