title: Molecular regulation of phosphate metabolism by fibroblast growth factor-23-klotho system.
abstract: Phosphorus is an essential nutrient and is routinely assimilated through consumption of food. The body's need of phosphate is usually fulfilled by intestinal absorption of this element from the consumed food, whereas its serum level is tightly regulated by renal excretion or reabsorption. Sodium-dependent phosphate transporters, located in the luminal side of the proximal tubular epithelial cells, have a molecular control on renal phosphate excretion and reabsorption. The systemic regulation of phosphate metabolism is a complex multiorgan process, and the identification of fibroblast growth factor-23 (FGF23)-Klotho system as a potent phosphatonin has provided new mechanistic insights into the homeostatic control of phosphate. Hypophosphatemia as a result of an increase in urinary phosphate wasting after activation of the FGF23-Klotho system is a common phenomenon, observed in both animal and human studies, whereas suppression of the FGF23-Klotho system leads to the development of hyperphosphatemia. This article will briefly summarize how delicate interactions of the FGF23-klotho system can regulate systemic phosphate homeostasis.
authors.affiliation: Department of Pathology, University of Texas Southwestern Medical Center, Dallas, USA.
authors.forename: Chung-Yi
authors.initials: CY
authors.lastname: Cheng
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuro-o
authors.forename: Mohammed S
authors.initials: MS
authors.lastname: Razzaque
mesh_terms: D000042:Absorption / Q000235:genetics / Q000502:physiology; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000235:genetics* / Q000378:metabolism*; D005786:Gene Expression Regulation; D005966:Glucuronidase / Q000235:genetics* / Q000378:metabolism*; D006706:Homeostasis / Q000235:genetics / Q000502:physiology; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000378:metabolism*; D000090265:Klotho Proteins; D010710:Phosphates / Q000378:metabolism*; D051436:Renal Insufficiency, Chronic / Q000378:metabolism; D050608:Sodium-Phosphate Cotransporter Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C000717427:FGF23 protein, human; D010710:Phosphates; D050608:Sodium-Phosphate Cotransporter Proteins; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23; D005966:Glucuronidase; D000090265:Klotho Proteins