Figure 3.

Association of phosphate intake and excretion with vascular remodeling. The phosphate pool is increased by the intake of phosphate-containing foods, including those fortified with phosphate additives. High systemic phosphate levels may lead to increased phosphate uptake by vascular smooth muscle cells, in turn accelerating vascular remodeling and calcification. In response to high phosphate, parathyroid hormone and FGF-23 promote the downregulation of phosphate transporters to increase urinary phosphate excretion (decreasing the phosphate pool). Conversely, high insulin levels observed in type 2 diabetes mellitus and obesity may decrease phosphate excretion (increasing the phosphate pool) by promoting the upregulation of phosphate transporters in urinary tubules.