title: Hearts of hypoxia-inducible factor prolyl 4-hydroxylase-2 hypomorphic mice show protection against acute ischemia-reperfusion injury.
abstract: Hypoxia-inducible factor (HIF) has a pivotal role in oxygen homeostasis and cardioprotection mediated by ischemic preconditioning. Its stability is regulated by HIF prolyl 4-hydroxylases (HIF-P4Hs), the inhibition of which is regarded as a promising strategy for treating diseases such as anemia and ischemia. We generated a viable Hif-p4h-2 hypomorph mouse line (Hif-p4h-2(gt/gt)) that expresses decreased amounts of wild-type Hif-p4h-2 mRNA: 8% in the heart; 15% in the skeletal muscle; 34-47% in the kidney, spleen, lung, and bladder; 60% in the brain; and 85% in the liver. These mice have no polycythemia and show no signs of the dilated cardiomyopathy or hyperactive angiogenesis observed in mice with broad spectrum conditional Hif-p4h-2 inactivation. We focused here on the effects of chronic Hif-p4h-2 deficiency in the heart. Hif-1 and Hif-2 were stabilized, and the mRNA levels of glucose transporter-1, several enzymes of glycolysis, pyruvate dehydrogenase kinase 1, angiopoietin-2, and adrenomedullin were increased in the Hif-p4h-2(gt/gt) hearts. When isolated Hif-p4h-2(gt/gt) hearts were subjected to ischemia-reperfusion, the recovery of mechanical function and coronary flow rate was significantly better than in wild type, while cumulative release of lactate dehydrogenase reflecting the infarct size was reduced. The preischemic amount of lactate was increased, and the ischemic versus preischemic [CrP]/[Cr] and [ATP] remained at higher levels in Hif-p4h-2(gt/gt) hearts, indicating enhanced glycolysis and an improved cellular energy state. Our data suggest that chronic stabilization of Hif-1alpha and Hif-2alpha by genetic knockdown of Hif-p4h-2 promotes cardioprotection by induction of many genes involved in glucose metabolism, cardiac function, and blood pressure.
authors.affiliation: Oulu Center for Cell-Matrix Research, and Department of Medical Biochemistry and Molecular Biology, University of Oulu, FIN-90014 Oulu, Finland.
authors.forename: Jaana
authors.initials: J
authors.lastname: Hyvärinen
authors.forename: Ilmo E
authors.initials: IE
authors.lastname: Hassinen
authors.forename: Raija
authors.initials: R
authors.lastname: Sormunen
authors.forename: Joni M
authors.initials: JM
authors.lastname: Mäki
authors.forename: Kari I
authors.initials: KI
authors.lastname: Kivirikko
authors.forename: Peppi
authors.initials: P
authors.lastname: Koivunen
authors.forename: Johanna
authors.initials: J
authors.lastname: Myllyharju
mesh_terms: D000208:Acute Disease; D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D003326:Coronary Circulation / Q000235:genetics; D049308:Dioxygenases / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000235:genetics / Q000378:metabolism*; D051272:Glucose Transporter Type 1 / Q000235:genetics / Q000378:metabolism; D006019:Glycolysis / Q000235:genetics; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism*; D015428:Myocardial Reperfusion Injury / Q000201:enzymology* / Q000235:genetics / Q000473:pathology / Q000517:prevention & control; D009206:Myocardium / Q000201:enzymology* / Q000473:pathology; D009928:Organ Specificity / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D049308:Dioxygenases; D005947:Glucose; D051272:Glucose Transporter Type 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007770:L-Lactate Dehydrogenase; D019344:Lactic Acid; D009124:Muscle Proteins; D017346:Protein Serine-Threonine Kinases; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D000099162:Endothelial PAS Domain-Containing Protein 1; C497443:Hif1a protein, mouse; C495678:Slc2a1 protein, mouse