Effect of salicin on gut inflammation and on selected groups of gut microbiota in dextran sodium sulfate induced mouse model of colitis

Objective and design: This study was undertaken to evaluate the anti-inflammatory effect of the pure compound salicin on dextran sulfate sodium (DSS)-induced colitis in a mouse model and to quantify the major gut bacteria during the treatment. Material or subjects: Experimental colitis was induced in Swiss albino mice by dissolving 2 % DSS in their drinking water for 7 days. Five mice were used in each group. Treatment: Salicin (100 and 200 mg per body weight) was administered daily through oral gavage for 7 days. Methods: Disease activity index (DAI), colon length, myeloperoxidase (MPO) assay, pro-inflammatory cytokine expression, histological changes and absolute number of gut microbiota were measured after treatment. Student's t test was applied for statistical analysis. Results: Salicin significantly attenuated DSS-induced DAI scores, shortening of colon length and tissue MPO activity. Salicin administration also effectively and dose-dependently prevented pro-inflammatory cytokine expression in DSS-induced colitis mice. Histological examination indicated that salicin suppressed edema, mucosal damage and the loss of crypts induced by DSS. Oral administration of salicin in DSS-treated mice prevented loss of gut microbiota during the short period of treatment. Conclusions: Salicin has an anti-inflammatory effect, and it may have therapeutic value in ameliorating inflammation during colitis.