Журнал нефрологии и терапии

Phosphorus Metabolism

Abstract

Rupesh Raina, Gaurav Garg, Sidharth Kumar Sethi, Martin J Schreiber, James F Simon and George Thomas

Phosphorus plays a pivotal role in various biological processes. Therefore, a deeper understanding of Phosphorus Homeostasis is essential for management and treatment of conditions causing an imbalance in phosphate metabolism. The widely understood parathyroid hormone (PTH) and vitamin D axis that governs this phosphate homeostasis has been critiqued for its inability to explain a few rare genetic and acquired conditions associated with phosphate imbalance. Such conditions are characterized by normal PTH and activated vitamin D hormone. For example, Tumor Induced osteomalacia, Autosomal Dominant hypophosphatemic rickets, and X-linked hypophosphatemic rickets.

Recent studies of such conditions have led to the discovery of additional factors that play an important role in phosphorus homeostasis. These phosphaturetic factors, called “Phosphatonins” include Fibroblast Growth Factor 23 (FGF-23), Fibroblast Growth Factor 7 (FGF7), Frizzled related protein 4 (FRP4), and matrix extracellular phosphoglycoprotein (MEPE).Out of these phosphatonins, FGF-23 has been extensively studied. This article aims to summarize the importance of phosphatonins in hypo- and hyperphosphatemic conditions along with the physiological and clinical importance of such factors. Furthermore, we tried to summarize current knowledge regarding diagnosis and management of such conditions.