title: Lung endothelial HO-1 targeting in vivo using lentiviral miRNA regulates apoptosis and autophagy during oxidant injury.
abstract: The lung endothelium is a major target for inflammatory and oxidative stress. Heme oxygenase-1 (HO-1) induction is a crucial defense mechanism during oxidant challenges, such as hyperoxia. The role of lung endothelial HO-1 during hyperoxia in vivo is not well defined. We engineered lentiviral vectors with microRNA (miRNA) sequences controlled by vascular endothelium cadherin (VE-cad) to study the specific role of lung endothelial HO-1. Wild-type (WT) murine lung endothelial cells (MLECs) or WT mice were treated with lentivirus and exposed to hyperoxia (95% oxygen). We detected HO-1 knockdown (∼55%) specifically in the lung endothelium. MLECs and lungs showed approximately a 2-fold increase in apoptosis and ROS generation after HO-1 silencing. We also demonstrate for the first time that silencing endothelial HO-1 has the same effect on lung injury and survival as silencing HO-1 in multiple lung cell types and that HO-1 regulates caspase 3 activation and autophagy in endothelium during hyperoxia. These studies demonstrate the utility of endothelial-targeted gene silencing in vivo using lentiviral miRNA constructs to assess gene function and that endothelial HO-1 is an important determinant of survival during hyperoxia.
authors.affiliation: 1Section of Pulmonary, Critical Care, and Sleep Medicine, Yale University School of Medicine, P.O. Box 208057, New Haven, CT 06520-8057, USA. patty.lee@yale.edu.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Ge
authors.initials: G
authors.lastname: Jiang
authors.forename: Maor
authors.initials: M
authors.lastname: Sauler
authors.forename: Patty J
authors.initials: PJ
authors.lastname: Lee
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001343:Autophagy; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D004727:Endothelium / Q000201:enzymology*; D055785:Gene Knockdown Techniques; D020868:Gene Silencing / Q000502:physiology; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D016086:Lentivirus / Q000502:physiology*; D008168:Lung / Q000201:enzymology*; D051379:Mice; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D010100:Oxygen / Q000633:toxicity; D017382:Reactive Oxygen Species
chemical_list: D035683:MicroRNAs; D017382:Reactive Oxygen Species; D051547:Heme Oxygenase-1; D053148:Caspase 3; D010100:Oxygen
keywords: VE-cadherin; cell death; heat-shock protein