title: Nitrosation-dependent caveolin 1 phosphorylation, ubiquitination, and degradation and its association with idiopathic pulmonary arterial hypertension.
abstract: In the present study, we tested the hypothesis that chronic inflammation and oxidative/nitrosative stress induce caveolin 1 (Cav-1) degradation, providing an underlying mechanism of endothelial cell activation/dysfunction and pulmonary vascular remodeling in patients with idiopathic pulmonary arterial hypertension (IPAH). We observed reduced Cav-1 protein despite increased Cav-1 messenger RNA expression and also endothelial nitric oxide synthase (eNOS) hyperphosphorylation in human pulmonary artery endothelial cells (PAECs) from patients with IPAH. In control human lung endothelial cell cultures, tumor necrosis factor α-induced nitric oxide (NO) production and S-nitrosation (SNO) of Cav-1 Cys-156 were associated with Src displacement and activation, Cav-1 Tyr-14 phosphorylation, and destabilization of Cav-1 oligomers within 5 minutes that could be blocked by eNOS or Src inhibition. Prolonged stimulation (72 hours) with NO donor DETANONOate reduced oligomerized and total Cav-1 levels by 40%-80%, similar to that observed in IPAH patient-derived PAECs. NO donor stimulation of endothelial cells for >72 hours, which was associated with sustained Src activation and Cav-1 phosphorylation, ubiquitination, and degradation, was blocked by NOS inhibitor L-NAME, Src inhibitor PP2, and proteosomal inhibitor MG132. Thus, chronic inflammation, sustained eNOS and Src signaling, and Cav-1 degradation may be important causal factors in the development of IPAH by promoting PAEC dysfunction/activation via sustained oxidative/nitrosative stress.
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Farnaz R
authors.initials: FR
authors.lastname: Bakhshi
authors.affiliation: Department of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Mao
authors.initials: M
authors.lastname: Mao
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Ayesha N
authors.initials: AN
authors.lastname: Shajahan
authors.affiliation: Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Tobias
authors.initials: T
authors.lastname: Piegeler
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Zhenlong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Olga
authors.initials: O
authors.lastname: Chernaya
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Tiffany
authors.initials: T
authors.lastname: Sharma
authors.affiliation: Pulmonary Division, James Hogg Research Centre Biobank, University of British Columbia, Vancouver, Canada.
authors.forename: W Mark
authors.initials: WM
authors.lastname: Elliott
authors.affiliation: Department of Physiology, Institute for Cardiovascular Research, Vrije Universiteit (VU) University Medical Center, Amsterdam, The Netherlands ; Department of Pulmonology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Robert
authors.initials: R
authors.lastname: Szulcek
authors.affiliation: Department of Pulmonology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Harm Jan
authors.initials: HJ
authors.lastname: Bogaard
authors.affiliation: Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
authors.forename: Suzy
authors.initials: S
authors.lastname: Comhair
authors.affiliation: Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
authors.forename: Serpil
authors.initials: S
authors.lastname: Erzurum
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA ; Department of Physiology, Institute for Cardiovascular Research, Vrije Universiteit (VU) University Medical Center, Amsterdam, The Netherlands.
authors.forename: Geerten P
authors.initials: GP
authors.lastname: van Nieuw Amerongen
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA ; Department of Medicine, Section of Cardiology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Marcelo G
authors.initials: MG
authors.lastname: Bonini
authors.affiliation: Department of Pharmacology, University of Illinois at Chicago, Chicago, Illinois, USA ; Department of Anesthesiology, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Minshall
keywords: Src; endothelial dysfunction; endothelial nitric oxide synthase (eNOS); oxidative stress; pulmonary arterial hypertension (PAH)