Phosphate feeding induces arterial medial calcification in uremic mice: role of serum phosphorus, fibroblast growth factor-23, and osteopontin

Kidney Int. 2009 Jun;75(12):1297-1307. doi: 10.1038/ki.2009.83. Epub 2009 Mar 25.

Abstract

Arterial medial calcification is a major complication in patients with chronic kidney disease and is a strong predictor of cardiovascular and all-cause mortality. We sought to determine the role of dietary phosphorus and the severity of uremia on vascular calcification in calcification-prone DBA/2 mice. Severe and moderate uremia was induced by renal ablation of varying magnitudes. Extensive arterial-medial calcification developed only when the uremic mice were placed on a high-phosphate diet. Arterial calcification in the severely uremic mice fed a high-phosphate diet was significantly associated with hyperphosphatemia. Moderately uremic mice on this diet were not hyperphosphatemic but had a significant rise in their serum levels of fibroblast growth factor 23 (FGF-23) and osteopontin that significantly correlated with arterial medial calcification. Although there was widespread arterial medial calcification, there was no histological evidence of atherosclerosis. At early stages of calcification, the osteochondrogenic markers Runx2 and osteopontin were upregulated, but the smooth muscle cell marker SM22alpha decreased in medial cells, as did the number of smooth muscle cells in extensively calcified regions. These findings suggest that phosphate loading and the severity of uremia play critical roles in controlling arterial medial calcification in mice. Further, FGF-23 and osteopontin may be markers and/or inducers of this process.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Arteries / metabolism
  • Arteries / pathology*
  • Calcinosis / blood*
  • Calcinosis / etiology*
  • Calcinosis / metabolism
  • Calcinosis / pathology
  • Calcium / blood
  • Calcium / metabolism
  • Disease Models, Animal
  • Female
  • Fibroblast Growth Factor-23
  • Fibroblast Growth Factors / blood
  • Humans
  • Mice
  • Mice, Inbred DBA
  • Osteopontin / blood
  • Osteopontin / metabolism
  • Phosphates / administration & dosage*
  • Phosphates / toxicity
  • Phosphorus / blood
  • Uremia / blood*
  • Uremia / complications*
  • Uremia / metabolism
  • Uremia / pathology
  • Vascular Diseases / blood*
  • Vascular Diseases / etiology*
  • Vascular Diseases / metabolism
  • Vascular Diseases / pathology

Substances

  • FGF23 protein, human
  • Fgf23 protein, mouse
  • Phosphates
  • Spp1 protein, mouse
  • Osteopontin
  • Phosphorus
  • Fibroblast Growth Factors
  • Fibroblast Growth Factor-23
  • Calcium