Abstract

This project (currently a component of the SCOR in ARDS) has described a novel paradigm for generation of reactive oxygen species (ROS) associated with acute alterations in shear stress (i.e., mechanotransduction) leading to rapid endothelial cell membrane depolarization, activation of membrane NADPH oxidase with ROS generation, Ca2+ influx, and NO release. Associated events include activation of cellular kinases (ERK1/2), activation of transcription factors (Nf-kappaB, AP-1) and cell proliferation. Intercellular release of Fe2+ associated with increased generation ROS results in oxidation of key cellular components manifested as lipid and protein oxidation. Thus, this mechanism can contribute to the pathophysiology of ARDS. A seminal finding of this project has been that the syndrome of ischemia-mediated ROS generation can be reproduced with endothelial cells in vitro provided they have been flow adapted. We propose 4 specific aims to investigate: 1) the mechanism for endothelial cell depolarization with emphasis on KATP channels as the potential flow sensor; 2) the pathway for ROS generation by the endothelium and in particular the role of NADPH oxidase components and their assembly; and 3) Ca2+ channels associated with calcium influx with special emphasis on the T-type voltage gated calcium channels.
Aim 4 will use protein/DNA array technology to determine activation of transcription factors, gene array technology to evaluate alterations in genes associated with cell proliferation and oxidant/antioxidant balance, and flow cytometry to evaluate cell proliferation. The experimental models that will be used include isolated lungs from rats and mice and pulmonary microvascular endothelial cells from rats, mice and humans. These studies will provide additional insights into a novel mechanism for initiation of endothelial ROS generation and subsequent cell signaling. This mechanism is of potential importance in ARDS as a source of ROS generation in association with focal vascular obstruction.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL075587-02
Application #
6832860
Study Section
Respiratory Physiology Study Section (RESP)
Program Officer
Harabin, Andrea L
Project Start
2003-12-09
Project End
2007-11-30
Budget Start
2004-12-01
Budget End
2005-11-30
Support Year
2
Fiscal Year
2005
Total Cost
$520,543
Indirect Cost

  Institution

Name
University of Pennsylvania
Department
Physiology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104

  Publications

Chatterjee, Shampa; Fujiwara, Keigi; Pérez, Néstor Gustavo et al. (2015) Mechanosignaling in the vasculature: emerging concepts in sensing, transduction and physiological responses. Am J Physiol Heart Circ Physiol 308:H1451-62
Chatterjee, Shampa; Nieman, Gary F; Christie, Jason D et al. (2014) Shear stress-related mechanosignaling with lung ischemia: lessons from basic research can inform lung transplantation. Am J Physiol Lung Cell Mol Physiol 307:L668-80
Chowdhury, Ibrul; Fisher, Aron B; Christofidou-Solomidou, Melpo et al. (2014) Keratinocyte growth factor and glucocorticoid induction of human peroxiredoxin 6 gene expression occur by independent mechanisms that are synergistic. Antioxid Redox Signal 20:391-402
Browning, Elizabeth; Wang, Hui; Hong, Nankang et al. (2014) Mechanotransduction drives post ischemic revascularization through K(ATP) channel closure and production of reactive oxygen species. Antioxid Redox Signal 20:872-86
Orndorff, Rebecca L; Hong, Nankang; Yu, Kevin et al. (2014) NOX2 in lung inflammation: quantum dot based in situ imaging of NOX2-mediated expression of vascular cell adhesion molecule-1. Am J Physiol Lung Cell Mol Physiol 306:L260-8
Noel, John; Wang, Hui; Hong, Nankang et al. (2013) PECAM-1 and caveolae form the mechanosensing complex necessary for NOX2 activation and angiogenic signaling with stopped flow in pulmonary endothelium. Am J Physiol Lung Cell Mol Physiol 305:L805-18
Chatterjee, Shampa; Browning, Elizabeth A; Hong, NanKang et al. (2012) Membrane depolarization is the trigger for PI3K/Akt activation and leads to the generation of ROS. Am J Physiol Heart Circ Physiol 302:H105-14
Browning, Elizabeth A; Chatterjee, Shampa; Fisher, Aron B (2012) Stop the flow: a paradigm for cell signaling mediated by reactive oxygen species in the pulmonary endothelium. Annu Rev Physiol 74:403-24
Lien, Yu-Chin; Feinstein, Sheldon I; Dodia, Chandra et al. (2012) The roles of peroxidase and phospholipase A2 activities of peroxiredoxin 6 in protecting pulmonary microvascular endothelial cells against peroxidative stress. Antioxid Redox Signal 16:440-51
Sorokina, Elena M; Feinstein, Sheldon I; Zhou, Suiping et al. (2011) Intracellular targeting of peroxiredoxin 6 to lysosomal organelles requires MAPK activity and binding to 14-3-3?. Am J Physiol Cell Physiol 300:C1430-41

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