Figure 5.
Silibinin feeding decreases β-catenin, cyclin D1 and COX-2 expression and PGE2 levels selectively in small intestinal polyps of APCmin/+ mice and inhibits β-catenin mediated transcriptional activity in vitro. Small intestinal segments or polyps were processed for IHC analyses or estimation for (A) nuclear β-catenin, (B) cyclin D1 and (D) COX-2 and PGE2 levels as detailed in Methods. Data represent mean ± SEM of six animals. *, P<0.001 versus control. Polyps from distal portion of small intestine from each group were also analyzed by immunoblotting for β-catenin and cyclin D1 levels. Values of band intensity adjusted with β-actin. C, TOP/FOPFlash reporter activity was measured using dual luciferase assay kit from Promega as described in detail in Methods. Data shown represents mean ± SEM of three independent observations. Sb, silibinin.