In Vitro Adverse Effects of Corticosteroid on TNF-α-mediated Responses by Pulmonary Microvascular Endothelial Cells

2008 ◽  
Vol 121 (2) ◽  
pp. S204-S204
Author(s):  
K ORIHARA ◽  
S FUKUDA ◽  
H FUJINAGA ◽  
K MATSUMOTO ◽  
H SAITO ◽  
...  
2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Adelheid Kratzer ◽  
Jonas Salys ◽  
Benjy Gonzalez ◽  
Hong Wei Chu ◽  
Martin Zamora ◽  
...  

Background and Objectives: Cell adhesion molecule CD146 is a transmembrane glycoprotein constitutively expressed in all types of endothelial cells (EC). It exists in two forms: a membrane-anchored form (CD146) and a soluble, extracellular and cleaved form (sCD146). The plasma concentration of sCD146 is modulated in inflammatory diseases that involve endothelial alterations. We investigated the role of endothelial CD146 in cigarette smoke-induced emphysema in vivo and in pulmonary endothelial cells (EC) in vitro . Methods: Sprague Dawley rats exposed to cigarette smoke for 2 months developed significant emphysematous changes (measured by mean linear intercept). Levels of sCD146 were subsequently measured in the circulation as well as in the bronchoalveolar lavage fluid (BALf) via ELISA. In vitro studies were carried out in rat pulmonary microvascular endothelial cells using CSE. Results: CD146 is highly expressed in rat pulmonary microvascular endothelial cells (RPMVEC) and to a much lower extent, in pulmonary macrovascular endothelial cells (RPAEC). Treatment of RPMVEC with cigarette smoke extract (CSE) in vitro resulted in decreased expression of membrane-bound CD146 as well as a reduced gene expression and increased sCD146 levels in the culture medium after 12 hours. Moreover, CSE-induced downregulation of CD146 expression resulted in increased vascular permeability of RPMVEC, as measured by EVANs Blue assay and migration of CFSE-labeled rat alveolar macrophage. Immunofluorescent staining revealed that CSE treatment resulted in translocation of membrane-bound CD146 into the nucleus. Subsequent western blot analysis showed changes in ERK and AKT activation and signaling. Similar results were found upon siRNA silencing of CD146, implicating a role for CD146 in tissue inflammation and integrity. Circulating levels of sCD146 were also elevated in plasma and BALf of patients with COPD and correlated, in part, with the presence of anti-endothelial autoantibodies. Additionally, we found decreased expression of membrane-bound CD146 in lung tissues of COPD patients. Conclusions: Our data suggest that CD146 plays an important role in pulmonary vascular EC function. Moreover, levels of circulating soluble CD146 can be a predictor of vascular endothelial cell injury.


Blood ◽  
2006 ◽  
Vol 109 (4) ◽  
pp. 1752-1755 ◽  
Author(s):  
Christopher C. Silliman ◽  
Brian R. Curtis ◽  
Patricia M. Kopko ◽  
Samina Y. Khan ◽  
Marguerite R. Kelher ◽  
...  

Abstract Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related mortality. Antibodies to HNA-3a are commonly implicated in TRALI. We hypothesized that HNA-3a antibodies prime neutrophils (PMNs) and cause PMN-mediated cytotoxicity through a two-event pathogenesis. Isolated HNA-3a+ or HNA-3a− PMNs were incubated with plasma containing HNA-3a antibodies implicated in TRALI, and their ability to prime the oxidase was measured. Human pulmonary microvascular endothelial cells (HMVECs) were activated with endotoxin or buffer, HNA-3a+ or HNA-3a− PMNs were added, and the coculture was incubated with plasma ± antibodies to HNA-3a. PMN-mediated damage was measured by counting viable HMVECs/mm2. Plasma containing HNA-3a antibodies primed the fMLP-activated respiratory burst of HNA-3a+, but not HNA-3a−, PMNs and elicited PMN-mediated damage of LPS-activated HMVECs when HNA-3a+, but not HNA-3a−, PMNs were used. Thus, antibodies to HNA-3a primed PMNs and caused PMN-mediated HMVEC cytotoxicity in a two-event model identical to biologic response modifiers implicated in TRALI.


2007 ◽  
Vol 102 (3) ◽  
pp. 949-955 ◽  
Author(s):  
Junlan Zhang ◽  
Yiqun Ling ◽  
Liping Tang ◽  
Bao Luo ◽  
Balu K. Chacko ◽  
...  

Hepatopulmonary syndrome (HPS) following rat common bile duct ligation results from pulmonary molecular changes that may be influenced by circulating TNF-α and increased vascular shear stress, through activation of NF-κB or Akt. Increased pulmonary microvascular endothelin B (ETB) receptor and endothelial nitric oxide synthase (eNOS) levels contribute to nitric oxide production and the development of experimental HPS. Pentoxifylline (PTX), a phosphodiesterase and nonspecific TNF-α inhibitor, ameliorates experimental HPS when begun before hepatic injury. However, how PTX influences the molecular events associated with initiation of experimental HPS after liver injury is established is unknown. We assessed the effects of PTX on the molecular and physiological features of HPS in vivo and on shear stress or TNF-α-mediated events in rat pulmonary microvascular endothelial cells in vitro. PTX significantly improved HPS without altering portal or systemic hemodynamics and downregulated pulmonary ETB receptor levels and eNOS expression and activation. These changes were associated with a reduction in circulating TNF levels and NF-κB activation and complete inhibition of Akt activation. In rat pulmonary microvascular endothelial cells, PTX inhibited shear stress-induced ETB receptor and eNOS expression and eNOS activation. These effects were also associated with inhibition of Akt activation and were reproduced by wortmanin. In contrast, TNF-α had no effects on endothelial ETB and eNOS alterations in vitro. PTX has direct effects in the pulmonary microvasculature, likely mediated through Akt inhibition, that ameliorate experimental HPS.


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