This is the conclusion of a recent study demonstrating that some bile acids behave just like hormones.
Hormone receptors are proteins that help regulate gene function.
Usually a receptor becomes activated or turned on when a specific hormone inserts itself into the receptor. Because there are currently more receptors than hormones, some receptors don't have hormones to activate them. These extra receptors are known as orphan receptors. FXR is such an orphan receptor. But the Baylor team, working with colleagues at Glaxo Wellcome Research and Development in Research Triangle, N.C., found that FXR is turned on by some bile acids.