Bile acids and their receptors.

Primary bile acids are synthetized from cholesterol within the liver and then transformed by the bacteria in the intestine to secondary bile acids. In addition to their involvement in digestion and fat solubilization, bile acids also act as signaling molecules. Several receptors are sensors of bile acids. Among these receptors, this review focuses on the nuclear receptor FXRα and the G-protein-coupled receptor TGR5. This review briefly presents the potential links between bile acids and cancers that are discussed in more details in the other articles of this special issue of Molecular Aspects of Medicine focused on "Bile acids, roles in integrative physiology and pathophysiology".