Abstract
FGF19, FGF21, and FGF23 form a unique subfamily of fibroblast growth factors. Because they contain intra-molecular disulfide bonds and show reduced affinity toward heparan sulfate located in the extracellular space, it is thought that, in contrast to other FGFs, they function as endocrine hormones. FGF23 and its co-receptor αKlotho are involved in the control of aging, but it is not known if the same holds true for FGF19, which can also signal through αKlotho. However, considerable evidence supports a role for FGF19 in controlling various aspects of metabolism. We have recently fully characterized FGF19/FGFR/co-factor interactions and signaling, and in the current manuscript discuss the contribution of the FGF19/FGFR4 axis to bile acid and glucose regulation.