UDCA and INT-777 suppress cardiac fibrosis triggered by IL-11 through involvement of TGR5

Abstract

AbstractCardiac fibrosis occurs in a wide range of cardiac diseases and is characterised by the transdifferentiation of cardiac fibroblasts (FB) into myofibroblasts (MFB). Myofibroblasts produce large quantities of extracellular matrix proteins, resulting in myocardial scar. The antifibrotic effect of the bile acid ursodeoxycholic acid (UDCA) is established in cases of liver fibrosis but not the adult myocardium.Our hypothesis is: UDCA is antifibrotic in the adult heart, mediated by the membrane bile acid receptor Takeda G protein-coupled receptor 5 (TGR5).We constructed a predictive network of fibrosis using RNA-seq datasets. We found that UDCA and it’s analogue INT-777, both reduced MFB markers in rat and human FBs and living myocardial slices (LMS). Utilising a knock-out mouse model, we show that the antifibrotic effect of UDCA is mediated by TGR5. Finally, we performed RNA-seq upon UDCA-treated human FB and integrated with our network of fibrosis, establishing the mechanism of TGR5 agonists.