Effect of inactivated schistosome ova on intestinal epithelial tight junctions during tinitrobenzene sulfonic acid-induced colitis / 中华消化杂志

ABSTRACT

Objective To observe the possible effect of inactivated schistosome ova on the expression of intestinal epithelial tight junctions ZO-1 and Occludin gene in mouse colitis induced by tinitrobenzene sulfonic acid (TNBS) and its mechanism. Methods Fifty mice were divided into control group (group A, n= 10),TNBS plus normal saline(NS) group(group B, n= 20) and TNBS plus inactivated schistosome ova group(group C, n= 20). Group C was exposed to 10 000 freeze-killed schistosome ova by intraperitoneal injection at day 14 and day 3 before colitis induction. Meanwhile,group B was exposed to 1 ml NS by intraperitoneal injection. The mice in group B and C were challenged with 3 mg TNBS to induce colitis. All mice were killed 7-day after colitis induction and assessed with following variables including mortality, pathological change with HE staining of colon.The transcription levels of ZO-1 and Oceludin in colon tissues were examined using Real-time PCR.The expression and distribution of ZO-1 and Occludin proteins were detected by Western blotting and immunohistochemistry. ResultsIn comparison with group B inactivated schistosome ova most effectively reduced the mortality (30% vs 15 %) and histopathologic severity of TNBS-induced colitis (4.21±0.40 vs 1.74±0.10). The transcription levels of ZO-1 and Occludin in group B were decreased compared with those in group A and group C (P<0.01). When compared with group B,group C showed a significant elevation of the alteration of ZO-1, Occludin proteins expression and localization. Conclusion The results clearly show that schistosome ova treatment reduced the severity of experimental colitis through the regulation of tight junction proteins.