title: The von Hippel-Lindau Chuvash mutation in mice alters cardiac substrate and high-energy phosphate metabolism.
abstract: Hypoxia-inducible factor (HIF) appears to function as a global master regulator of cellular and systemic responses to hypoxia. HIF pathway manipulation is of therapeutic interest; however, global systemic upregulation of HIF may have as yet unknown effects on multiple processes. We used a mouse model of Chuvash polycythemia (CP), a rare genetic disorder that modestly increases expression of HIF target genes in normoxia, to understand what these effects might be within the heart. An integrated in and ex vivo approach was employed. Compared with wild-type controls, CP mice had evidence (using in vivo magnetic resonance imaging) of pulmonary hypertension, right ventricular hypertrophy, and increased left ventricular ejection fraction. Glycolytic flux (measured using [(3)H]glucose) in the isolated contracting perfused CP heart was 1.8-fold higher. Net lactate efflux was 1.5-fold higher. Furthermore, in vivo (13)C-magnetic resonance spectroscopy (MRS) of hyperpolarized [(13)C1]pyruvate revealed a twofold increase in real-time flux through lactate dehydrogenase in the CP hearts and a 1.6-fold increase through pyruvate dehydrogenase. (31)P-MRS of perfused CP hearts under increased workload (isoproterenol infusion) demonstrated increased depletion of phosphocreatine relative to ATP. Intriguingly, no changes in cardiac gene expression were detected. In summary, a modest systemic dysregulation of the HIF pathway resulted in clear alterations in cardiac metabolism and energetics. However, in contrast to studies generating high HIF levels within the heart, the CP mice showed neither the predicted changes in gene expression nor any degree of LV impairment. We conclude that the effects of manipulating HIF on the heart are dose dependent.
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Mary
authors.initials: M
authors.lastname: Slingo
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Mark
authors.initials: M
authors.lastname: Cole
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Carolyn
authors.initials: C
authors.lastname: Carr
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Curtis
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Michael
authors.identifier: 0000-0002-1217-4660
authors.initials: M
authors.lastname: Dodd
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Lucia
authors.initials: L
authors.lastname: Giles
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Heather
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Damian
authors.initials: D
authors.lastname: Tyler
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Kieran
authors.initials: K
authors.lastname: Clarke
authors.affiliation: Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom peter.robbins@dpag.ox.ac.uk.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Robbins
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D051017:Apoptosis Regulatory Proteins; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D051792:Basic Helix-Loop-Helix Proteins; D002247:Carbon Isotopes; D002316:Cardiotonic Agents / Q000494:pharmacology; D004195:Disease Models, Animal; D005947:Glucose / Q000378:metabolism; D006019:Glycolysis; D006321:Heart / Q000187:drug effects / Q000503:physiopathology*; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism*; D017380:Hypertrophy, Right Ventricular / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D000067268:Isolated Heart Preparation; D007545:Isoproterenol / Q000494:pharmacology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D009154:Mutation; D009206:Myocardium / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism; D011086:Polycythemia / Q000151:congenital* / Q000000981:diagnostic imaging / Q000235:genetics / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism; D012097:Repressor Proteins; D013318:Stroke Volume; D014157:Transcription Factors; D014316:Tritium; D051794:Von Hippel-Lindau Tumor Suppressor Protein / Q000235:genetics; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D000255:Adenosine Triphosphate; D051017:Apoptosis Regulatory Proteins; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D051792:Basic Helix-Loop-Helix Proteins; D002247:Carbon Isotopes; D002316:Cardiotonic Agents; D005947:Glucose; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007545:Isoproterenol; D007770:L-Lactate Dehydrogenase; D010710:Phosphates; D010725:Phosphocreatine; D019289:Pyruvic Acid; D012097:Repressor Proteins; D014157:Transcription Factors; D014316:Tritium; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D000099162:Endothelial PAS Domain-Containing Protein 1; C497397:Arnt protein, mouse; C497443:Hif1a protein, mouse; C444643:Hif3a protein, mouse; C494469:VHL protein, mouse
keywords: hyperpolarized pyruvate; hypoxia-inducible factor; magnetic resonance imaging