Background: Wei Chang An pill (WCA) is a traditional Chinese pharmaceutical preparation which has been widely used to treat various gastrointestinal diseases including Ulcerative colitis (UC). The aim of our study was investigate the inhibitory effect and mechanism of WCA in the treatment of 2,4,6-trinitro-benzenesulfonic acid (TNBS)-induced UC in rats.
Methods: We established the TNBS-induced UC model and then WCA was administrated orally for one week. Body weight, colon lengths, Disease Activity Index (DAI) score and Colon Mucosa Damage Index (CMDI) score were recorded. The expression of cytokines factors in LPS-stimulated THP-1 cells was recorded to evaluate the anti-inflammatory effects of WCA and its herb active ingredients. Immunohistochemistry and immunofluorescence were used to evaluate the Epithelial-Mesenchymal Transition (EMT) process in UC rats and Caco-2 cells which were induced by LPS-stimulated THP-1 cells uponWCA treatment.
Results: WCA significantly decreased the body weight loss, higher DAI and CMDI score, colon length shortening and histological damage in UC rats. Furthermore, both of the activities of myeloperoxidase dismutase (MPO) and the mRNA expressions of cytokine in UC tissues were significantly inhibited. In THP-1 cells, the mRNA expressions of IP-10, TNF-α, IL-6 and IkBα were significantly suppressed by WCA or its active ingredients. In UC rats and Caco-2 cells, both of their EMT process were strongly suppressed by WCA.
Conclusion: These results show that through improving inflammatory microenvironment to inhibit the EMT process, WCA retarded the development of UC in rats to play its anti-inflammatory effect.