[Endocrine control of serum phosphate: from the discoveries of phosphatonins to novel therapies].

Phosphate is absorbed through the gut, stored in the bone and reabsorbed through the proximal renal tubule. More importantly, PTH and FGF23 have been identified as the main phosphaturic factors that control the expression of the phosphate co-transporters NaPi-IIa et IIc. By allowing the adjustment of the urinary phosphate reabsorption, these two phosphatonins play a major role in bone and tooth mineralization and growth. Recently, novel therapies have successfully targeted the FGF23 signaling pathway to treat the hypophosphatemia in patients affected with molecular defects of this pathway (mutations in the PHEX gene).