Developments in bile salt based therapies: A critical overview

Bile acids, amphipathic molecules known for their facilitating role in fat absorption, are also recognized as signalling molecules acting via nuclear and membrane receptors. Of the bile acid-activated receptors, the Farnesoid X Receptor (FXR) and the G protein-coupled bile acid receptor-1 (Gpbar1 or TGR5) have been studied most extensively. Bile acid signaling is critical in the regulation of bile acid metabolism itself, but it also plays a significant role in glucose, lipid and energy metabolism. Activation of FXR and TGR5 leads to reduced hepatic bile salt load, improved insulin sensitivity and glucose regulation, increased energy expenditure, and anti-inflammatory effects. These beneficial effects render bile acid signaling an interesting therapeutic target for the treatment of diseases such as cholestasis, non-alcoholic fatty liver disease, and diabetes. Here, we summarize recent findings on bile acid signaling and discuss potential and current limitations of bile acid receptor agonist and modulators of bile acid transport as future therapeutics for a wide-spectrum of diseases.