title: Disruption of hypoxia-inducible transcription factor-prolyl hydroxylase domain-1 (PHD-1-/-) attenuates ex vivo myocardial ischemia/reperfusion injury through hypoxia-inducible factor-1α transcription factor and its target genes in mice.
abstract: Hypoxia-inducible transcription factor (HIF)-prolyl hydroxylases domain (PHD-1-3) are oxygen sensors that regulate the stability of the HIFs in an oxygen-dependent manner. Suppression of PHD enzymes leads to stabilization of HIFs and offers a potential treatment option for many ischemic disorders, such as peripheral artery occlusive disease, myocardial infarction, and stroke. Here, we show that homozygous disruption of PHD-1 (PHD-1(-/-)) could facilitate HIF-1α-mediated cardioprotection in ischemia/reperfused (I/R) myocardium. Wild-type (WT) and PHD-1(-/-) mice were randomized into WT time-matched control (TMC), PHD-1(-/-) TMC (PHD1TMC), WT I/R, and PHD-1(-/-) I/R (PHD1IR). Isolated hearts from each group were subjected to 30 min of global ischemia followed by 2 h of reperfusion. TMC hearts were perfused for 2 h 30 min without ischemia. Decreased infarct size (35%±0.6% vs. 49%±0.4%) and apoptotic cardiomyocytes (106±13 vs. 233±21 counts/100 high-power field) were observed in PHD1IR compared to wild-type ischemia/reperfusion (WTIR). Protein expression of HIF-1α was significantly increased in PHD1IR compared to WTIR. mRNA expression of β-catenin (1.9-fold), endothelial nitric oxide synthase (1.9-fold), p65 (1.9-fold), and Bcl-2 (2.7-fold) were upregulated in the PHD1IR compared with WTIR, which was studied by real-time quantitative polymerase chain reaction. Further, gel-shift analysis showed increased DNA binding activity of HIF-1α and nuclear factor-kappaB in PHD1IR compared to WTIR. In addition, nuclear translocation of β-catenin was increased in PHD1IR compared with WTIR. These findings indicated that silencing of PHD-1 attenuates myocardial I/R injury probably by enhancing HIF-1α/β-catenin/endothelial nitric oxide synthase/nuclear factor-kappaB and Bcl-2 signaling pathway.
authors.affiliation: Molecular Cardiology and Angiogenesis Laboratory, Department of Surgery, University of Connecticut School of Medicine, 263 Farmington Ave., Farmington, CT 06032-1110, USA.
authors.forename: Ram Sudheer
authors.initials: RS
authors.lastname: Adluri
authors.forename: Mahesh
authors.initials: M
authors.lastname: Thirunavukkarasu
authors.forename: Nageswara Rao
authors.initials: NR
authors.lastname: Dunna
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhan
authors.forename: Babatunde
authors.initials: B
authors.lastname: Oriowo
authors.forename: Kotaro
authors.initials: K
authors.lastname: Takeda
authors.forename: Juan A
authors.initials: JA
authors.lastname: Sanchez
authors.forename: Hajime
authors.initials: H
authors.lastname: Otani
authors.forename: Gautam
authors.initials: G
authors.lastname: Maulik
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Fong
authors.forename: Nilanjana
authors.initials: N
authors.lastname: Maulik
mesh_terms: D000818:Animals; D017209:Apoptosis; D002467:Cell Nucleus / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D015870:Gene Expression; D055786:Gene Knockout Techniques; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000737:chemistry* / Q000378:metabolism; D066298:In Vitro Techniques; D051379:Mice; D018345:Mice, Knockout; D017202:Myocardial Ischemia / Q000235:genetics / Q000473:pathology*; D015428:Myocardial Reperfusion Injury / Q000235:genetics / Q000473:pathology*; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D011393:Procollagen-Proline Dioxygenase / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D016277:Ventricular Function, Left; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism
chemical_list: C497443:Hif1a protein, mouse; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D016328:NF-kappa B; D019253:Proto-Oncogene Proteins c-bcl-2; D051176:beta Catenin; C522721:PHD1 protein, mouse; D011393:Procollagen-Proline Dioxygenase; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse