Evaluating the efficacy of potential drugs for intestinal fibrosis using precision-cut tissue slices

Intestinal fibrosis (IF) is a common complication in Crohn's disease. Currently, there are no drugs registered to treat IF and the sole therapy is intestinal resection. Transforming growth factor (TGF)-beta and platelet-derived growth factor (PDGF) play a key role in IF and are the main targets for potential treatment. Recently, we developed a novel model for the early onset of IF using precision-cut intestinal slices (PCIS). Our objective was to investigate the antifibrotic effect of some potential antifibrotic compounds, including TGF-beta and PDGF-pathway inhibitors, by using the murine PCIS fibrosis model. Murine PCIS were incubated up to 48 h. The viability was assessed by evaluating the ATP content of the PCIS. Gene expression of the fibrosis markers pro-collagen 1a1 (Col1a1), heat shock protein 47 (Hsp47) and fibronectin (Fn2) were determined by qPCR. The effects of antifibrotic drugs mainly inhibiting the TGF-beta pathway: valproic acid (VPA), tetrandrine (Tet), pirfenidone (Pir), and LY2109761 (LY) and mainly inhibiting the PDGF pathway: imatinib (Ima), sorafenib (Sor), and sunitinib (Sun) were determined at the maximal non-toxic concentrations. Murine PCIS remained viable up to 48 h of incubation and showed increased gene expression of the fibrosis markers (Col1a1, 0.6; Hsp47, 4.0 and Fn2, 4.4 fold). After 48 h, VPA and Tet down-regulated Hsp47 gene expression 2.0 and 1.7 fold, respectively. Furthermore, Fn2 gene expression was also decreased 2.1 fold by Tet. Meanwhile, Pir decreased Col1a1, Hsp47, and Fn2 gene expression 2.2, 1.5, and 1.2 fold, respectively. All investigated markers of fibrosis were down-regulated by LY (Col1a1, 9.0; Hsp47, 1.9 and Fn2, 2.7 fold). Sun decreased the expression of Col1a1, 1.6; Hsp47, 3.3 and Fn2, 2.3 fold, while Sor only down-regulated Hsp47, 1.3 fold. In contrast, Ima did not affect the expression of fibrosis markers. From the compounds studied, the TGF-beta-inhibitors; Tet, Pir, and LY and only one PDGF-inhibitor, Sun, showed potential antifibrotic effect on gene expression of fibrosis markers in murine PCIS. Thus, PCIS is a promising model to evaluate the antifibrotic effect of potential drugs for intestinal fibrosis.