FGF19

Fibroblast Growth Factor 19, also known as FGF19, is a member of the fibroblast growth factor family. It is a hormone that plays a significant role in regulating bile acid metabolism in the liver. FGF19 is primarily produced by the ileum, a section of the small intestine, in response to the presence of bile acids. Its production is stimulated by bile acids that have returned to the ileum after digestion.

Once released into the bloodstream, FGF19 travels to the liver. There, it binds to its receptor, FGFR4, which is predominantly expressed on hepatocytes, the main cell type in the liver. This binding triggers a signaling cascade that leads to the downregulation of bile acid synthesis. Specifically, FGF19 inhibits the activity of CYP7A1, a key enzyme involved in the de novo synthesis of bile acids. By doing so, FGF19 acts as a crucial feedback mechanism, preventing the excessive accumulation of bile acids in the body.

Disruptions in FGF19 signaling have been implicated in various metabolic disorders, including obesity and type 2 diabetes. Its role in bile acid homeostasis also makes it a potential therapeutic target for conditions related to liver disease and metabolic syndrome. Research into FGF19 continues to explore its multifaceted functions and potential applications in treating these conditions.