Anti-inflammatory effects of Pulvis Fellis Suis extract in mice with ulcerative colitis

Ethnopharmacological relevance: Pulvis Fellis Suis is used in folk medicines to treat intestinal diseases, acute pharyngitis, whooping cough and asthma in China. Although several reports indicate that Pulvis Fellis Suis display diverse biological activities, such as antibacterial, anti-inflammatory and anti-infusorian effects, its effects on ulcerative colitis have not been previously explored. Aim of the study: The purpose of the present study is to assess the anti-inflammatory effect of Pulvis Fellis Suis (PFS) extract in acute ulcerative colitis model induced by trinitrobenzene sulfonic acid (TNBS) in mice. Materials and methods: Different doses of Pulvis Fellis Suis extract (100, 200 and 400 mg/kg/day) and sulfasalazine (500 mg/kg/day) were administered by gavage for 7 days after the induction of colitis with TNBS. The efficacy of PFS was studied by macroscopical and histological scoring systems as well as myeloperoxidase (MPO) activity. Serum levels, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were assayed by enzyme-linked immunoassay. The expression of cyclooxygenase (COX)-2 in the colons was assessed by immunohistochemical analysis. Results: Treatment with PFS significantly attenuated macroscopic damage as compared with TNBS (P < 0.01). Histological analysis showed that PFS improved the microscopic structure and preserved some areas of the colonic mucosa structure. In addition, administration of PFS effectively inhibited COX-2 protein expression and MPO activity accumulation. TNF-α and IL-6 levels were also diminished dose-dependently (P < 0.05, P < 0.01), and IL-6 level obtained had no significant results by small dose of PFS. All the effects of these parameters were comparable to that of the standard sulfasalazine, especially at the highest dose level. Conclusions: We have shown for the first time that PFS has an anti-inflammatory effect in TNBS-induced ulcerative colitis which might be related to the reduction of up-regulated TNF-α and IL-6 production, and that it may have therapeutic value in the setting of inflammatory bowel disease (IBD).