Interplay Between FGF23, Phosphate, and Molecules Involved in Phosphate Sensing
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Purpose of Review
Despite the important progress made in understanding the regulation of phosphate (Pi) homeostasis over the past 20 years, the mechanisms underlying the very early step leading to the regulating cascade involving multiple hormones (PTH, vitamin D, FGF23) and organs (kidney, intestine, bone, parathyroid glands) are not deciphered. Particularly, knowledge on the Pi-sensing mechanism present within or on the surface of the cell that is able to detect changes in serum or local Pi concentrations and trigger an appropriate FGF23 synthesis/secretion is limited or absent.
Several molecular actors have recently been involved as potential key players in Pi sensing and Pi-dependent control of FGF23 secretion. Among them, the PiT1/Slc20a1 and PiT2/Slc20a2 proteins are standing out.
We are just beginning to accumulate in vitro and in vivo data that will provide invaluable molecular tools to explore and understand the integrated response of the body to variations of Pi concentration.
KeywordsPhosphate sensing FGF23 Slc20a1 Slc20a2
This work was supported by grants from Institut National de la Santé et de la Recherche Médicale (INSERM), Région des Pays de la Loire (grants “Nouvelle Equipe/Nouvelle Thématique”, “Senseo,” and “Adipos”).
Compliance with Ethical Standards
Conflict of Interest
Nina Bon, Sarah Beck-Cormier, and Laurent Beck each declare no potential conflicts of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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