Bile Acids and Portal Hypertension

The recent discovery of bile acid (BA) receptors and a better delineation of the multiple roles of BAs in relevant biological processes have revamped BA research. The vasoactive actions of BAs were recognized more than three decades ago but the underlying mechanisms of the BA-induced vasorelaxation are now being clarified. Recent evidence shows that the BA receptors FXR and TGR5 are expressed in endothelial cells and may have important effects on both systemic and portal circulation. The availability of genetically engineered mice with ablation of BA receptors and the development of BA receptor agonists has allowed to explore the modulation of FXR and, in a lesser extent, of TGR5 in the setting of portal hypertension (PHT) with promising results. In this review, we summarize recent data on how BA-dependent pathways influence several processes that impact in PHT and the preclinical data showing that pharmacological modulation of those pathways may hold promise in the treatment of PHT.