Protective Role of Bokusoku in Dextran Sulphate Sodium Induced Colitis via Inhibition of Epithelial-mesenchymal Transition

Abstract

Inflammatory bowel disease (IBD) is referred to as uncontrolled mucosal inflammation resulting from an abnormal immune response against unknown environmental triggers. Fibrosis is considered to be an important feature in the progression of IBD and the most likely mechanism involved in the activation of fibroblasts is epithelial-mesenchymal transition (EMT). Bokusoku is the main component of the Japanese Kampo medicine Jumihaidokuto, and is mainly prescribed for various inflammatory diseases. We examined the beneficial effect of bokusoku in IBD associated with fibrosis and inflammation of the intestinal mucosal membrane. We used C57BL/6 female mice, divided into three groups, all of which received 3％ dextran sulphate sodium (DSS) in drinking water during the experimental period (8 days). Standard group mice received sulphasalazine 80 mg/kg/day po, treatment group mice received bokusoku 100 mg/kg/day po and the DSS control group received an equal volume of distilled water. Normal control group mice received plain drinking water. Bokusoku treatment significantly alleviated fibrosis and inflammation by regulating EMT and decreased the expression of pro-inflammatory cytokines associated with the disease pathogenesis and can thus be considered a potent agent for the treatment of colitis.