What does FGF23 do?
The FGF23 gene provides instructions for making a protein called fibroblast growth factor 23, which is produced in bone cells. This protein is necessary in regulating the phosphate levels within the body (phosphate homeostasis).
Is FGF23 a Phosphatonin?
The key phosphatonin appears to be fibroblast growth factor-23 (FGF23) (8–10).
Is FGF a hormone?
Hormone-like Fgfs play roles in metabolism at postnatal stages, although they also play roles in development at embryonic stages. Fgf15/19 regulates bile acid metabolism in the liver. Fgf21 regulates lipid metabolism in the white adipose tissue.
What stimulates FGF23 secretion?
Recently, it has been shown that leptin, a hormone secreted by white adipose tissue that acts centrally on hypothalamus and peripherally on other organs to control energy intake, expenditure, and bone homeostasis, stimulates FGF23 production in bone (205).
How does FGF23 cause low blood phosphate levels?
FGF23 is produced by bone and reduces serum phosphate level by suppressing phosphate reabsorption in proximal tubules and intestinal phosphate absorption through lowering 1,25-dihydroxyvitamin D level.
Why is FGF23 elevated in CKD?
In patients with chronic kidney disease (CKD), circulating FGF23 levels are progressively increased to compensate for persistent phosphate retention, but this results in reduced renal production of 1,25-dihydroxyvitamin D and leads to hypersecretion of parathyroid hormone.
When is FGF23 secreted?
FGF23 is secreted by osteocytes in response to increased calcitriol. FGF23 acts on the kidneys, where it decreases the expression of NPT2, a sodium-phosphate cotransporter in the proximal tubule. Thus, FGF23 decreases the reabsorption of calcium and increases excretion of phosphate.
Does phosphate stimulate FGF23?
Calcium, phosphate, and PTH failed to stimulate FGF23 mRNA levels or FGF23 promoter activity in osteoblast cultures, but these factors have variably been associated with increased circulating FGF23 levels. Bone-derived factors also regulate FGF23 expression.
Is FGF a kinase?
FGFR is a receptor tyrosine kinase of ∼800 amino acids with several domains including three extracellular immunoglobulin-like domains (I, II, and III), a transmembrane domain (TM), and two intracellular tyrosine kinase domains (TK1 and TK2).
What is the meaning of FGF?
FGF
| Acronym | Definition |
|---|---|
| FGF | Fine Girl Friday |
| FGF | Feel-Good Factor |
| FGF | Fake Girlfriend |
| FGF | Federación Gallega de Fútbol (Spain) |
How does FGF23 reduce dietary calcium and phosphate absorption from the intestine?
FGF-23 downregulates the phosphate transporters Napt2a and 2c, resulting in decreased phosphate reabsorption. It also downregulates 1α-hydroxylase, which decreases the production of calcitriol resulting in decreased intestinal phosphate and calcium reabsorption.
Why does FGF23 increase in CKD?
What does FGF 23 stand for?
FGF 23 (Fibroblast Growth Factor 23) – FGF 23 is a major regulator of phosphate homeostasis. It is mainly produced in bone and also in the thymus and brain. Intact FGF 23 is biologically active. High serum FGF 23 levels stimulate FGF 23 expression.
How does intact FGF 23 work?
Intact FGF 23 is biologically active. High serum FGF 23 levels stimulate FGF 23 expression. It interacts with a specific receptor in renal tubular cells, decreasing the expression of type IIa sodium/phosphate cotransponders and resulting in decreased phosphate reabsorption.
How does FGF 23 affect phosphate reabsorption?
High serum FGF 23 levels stimulate FGF 23 expression. It interacts with a specific receptor in renal tubular cells, decreasing the expression of type IIa sodium/phosphate cotransponders and resulting in decreased phosphate reabsorption. FGF reduces the formation of 1, 25 dihydroxy vitamin D resulting in reduced phosphate reabsorption.