The von Hippel-Lindau Chuvash mutation promotes pulmonary hypertension and fibrosis in mice.
Mutation of the von Hippel-Lindau (VHL) tumor suppressor protein at codon 200 (R200W) is associated with a disease known as Chuvash polycythemia. In addition to polycythemia, Chuvash patients have pulmonary hypertension and increased respiratory rates, although the pathophysiological basis of these symptoms is unclear. Here we sought to address this issue by studying mice homozygous for the R200W Vhl mutation (VhlR/R mice) as a model for Chuvash disease. These mice developed pulmonary hypertension independently of polycythemia and enhanced normoxic respiration similar to Chuvash patients, further validating VhlR/R mice as a model for Chuvash disease. Lungs from VhlR/R mice exhibited pulmonary vascular remodeling, hemorrhage, edema, and macrophage infiltration, and lungs from older mice also exhibited fibrosis. HIF-2alpha activity was increased in lungs from VhlR/R mice, and heterozygosity for Hif2a, but not Hif1a, genetically suppressed both the polycythemia and pulmonary hypertension in the VhlR/R mice. Furthermore, Hif2a heterozygosity resulted in partial protection against vascular remodeling, hemorrhage, and edema, but not inflammation, in VhlR/R lungs, suggesting a selective role for HIF-2alpha in the pulmonary pathology and thereby providing insight into the mechanisms underlying pulmonary hypertension. These findings strongly support a dependency of the Chuvash phenotype on HIF-2alpha and suggest potential treatments for Chuvash patients.
Hickey
Michele M
MM
Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, 19104, USA.
Richardson
Theresa
T
Wang
Tao
T
Mosqueira
Matias
M
Arguiri
Evguenia
E
Yu
Hongwei
H
Yu
Qian-Chun
QC
Solomides
Charalambos C
CC
Morrisey
Edward E
EE
Khurana
Tejvir S
TS
Christofidou-Solomidou
Melpo
M
Simon
M Celeste
MC
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D003062:Codon / Q000235:genetics; D004195:Disease Models, Animal; D006470:Hemorrhage / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D006976:Hypertension, Pulmonary / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008817:Mice, Mutant Strains; D009154:Mutation; D011086:Polycythemia / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011654:Pulmonary Edema / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011658:Pulmonary Fibrosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D051794:Von Hippel-Lindau Tumor Suppressor Protein / Q000235:genetics / Q000378:metabolism*; D006623:von Hippel-Lindau Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000099162:Endothelial PAS Domain-Containing Protein 1
D051792:Basic Helix-Loop-Helix Proteins; D003062:Codon; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D000099162:Endothelial PAS Domain-Containing Protein 1; C497443:Hif1a protein, mouse