Fibroblast growth factor 15 is a
protein in mouse encoded by the ''Fgf15''
gene. It is a member of the
fibroblast growth factor (FGF) family but, like
FGF19,
FGF21 and
FGF23, has endocrine functions.
FGF19 is the orthologous protein in humans. They are often referred together as
FGF15/19.
Identification
FGF15 was first described in developing
mouse brain. There is no human FGF15.
Structure
The mouse ''Fgf15'' gene is syntenic with the human ''FGF19'' gene. FGF15 and FGF19 proteins share about 50% amino acid identity, are found in the same tissues, and have similar functions in mouse and humans.
Functions
FGF15 is found in the absorptive cells of the mouse
ileum and plays an important role in feedback inhibition of hepatic
bile acid synthesis. FGF15 (and FGF19 in humans) function as hormones produced in response to
bile acid
Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts.
Primary b ...
absorption acting on the farnesoid X receptor
FXR, are secreted into the portal venous circulation and bind onto the liver membrane receptor
FGFR4/β-Klotho and repress bile acid synthesis by the ''Cyp7a1'' gene.
In a mouse model of
chronic diarrhea
Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin wi ...
due to
bile acid malabsorption, FGF15 administration, or stimulation of its production, reduced the bile acid loss by inhibiting new synthesis.
FGF15 has effects on energy homeostasis. ''Fgf15''-knock-out mice have reduced liver glycogen storage and are glucose-intolerant.
FGF15 has been implicated in liver regeneration and repair. ''Fgf15''-deficient mice have impaired regeneration.
References
{{Growth factor receptor modulators
Growth factors
Peptide hormones