Understanding the Regulatory Mechanisms of Phosphorus Metabolism

―From the Basics to Recent Topics―

Abstract

Phosphorus is one of the essential elements of the human body and is required for a variety of processes, including ATP synthesis, signal transduction, and bone mineralization. Phosphorus is found in various foods, such as those with animal protein sources like meat and fish, as well as in dairy products and seeds, and therefore is not deficient or absent in a normal diet. Blood phosphate (Pi) concentrations are controlled by intestinal absorption, bone formation, bone resorption, and renal excretion and reabsorption, which maintain a balance in response to various factors. Intestinal and renal Pi (re)absorption are mediated by Pi transporters, which are strictly mediated by the phosphorus-regulating hormones parathyroid hormone, active vitamin D, and fibroblast growth factor 23. We review the basic mechanisms responsible for regulation of phosphorus homeostasis, as well as novel regulators of phosphorus metabolism that we have recently identified.