Endogenous and exogenous catalase in reoxygenation lung injury

1992 ◽  
Vol 72 (3) ◽  
pp. 858-864 ◽  
Author(s):  
R. M. Jackson ◽  
W. J. Russell ◽  
C. F. Veal
Keyword(s):  
Lung Injury ◽  
Pulmonary Edema ◽  
Catalase Activity ◽  
Neutrophil Infiltration ◽  
Progressive Increase ◽  
H2o2 Production ◽  
Lung Collapse ◽  
Extracellular Medium ◽  
Specific Effects ◽  
Reexpansion Pulmonary Edema

Reexpansion pulmonary edema parallels reperfusion (reoxygenation) injuries in other organs in that hypoxic and hypoperfused lung tissue develops increased vascular permeability and neutrophil infiltration after reexpansion. This study investigated endogenous lung catalase activity and H2O2 production during hypoxia (produced by lung collapse) and after reoxygenation (resulting from reexpansion), in addition to assessing the effects of exogenous catalase infusion on the development of unilateral pulmonary edema after reexpansion. Lung collapse resulted in a progressive increase in endogenous catalase activity after 3 (14%) and 7 days (23%), while activities in contralateral left lungs did not change (normal left lungs averaged 180 +/- 11 units/mg DNA). Tissue from control left lungs released H2O2 into the extracellular medium at a rate calculated to be 242 +/- 34 nmol.h-1.lung-1. No significant change in extracellular release of H2O2 occurred after 7 days of right lung collapse. However, after reexpansion of the previously collapsed right lungs for 2 h, H2O2 release from both reexpanded right and contralateral left lungs significantly increased (88 and 60%, respectively) compared with controls. Infusion of exogenous catalase significantly increased plasma and lung catalase activities. Exogenous catalase infusion prevented neither the increase in lung permeability nor the infiltration with neutrophils that typically occurs in reexpanded lungs. These data indicate that lung hypoxia/reoxygenation, induced by sequential collapse and reexpansion, has specific effects on endogenous lung catalase activity and H2O2 release. However, exogenous catalase does not prevent reexpansion pulmonary edema, eliminating extracellular (but not intracellular) H2O2 as an important mediator of unilateral lung injury in this model.

Effects of hypoxia and reoxygenation on lung glutathione system

1990 ◽  
Vol 259 (2) ◽  
pp. H518-H524 ◽  
Author(s):  
R. M. Jackson ◽  
C. F. Veal
Keyword(s):  
Glutathione Peroxidase ◽  
Lung Tissue ◽  
Neutrophil Infiltration ◽  
Lavage Fluid ◽  
Glutathione System ◽  
Glutathione Disulfide ◽  
Lung Collapse ◽  
Total Glutathione ◽  
Reexpansion Pulmonary Edema ◽  
The Right

Reexpansion pulmonary edema (RPE) parallels reperfusion (reoxygenation) injuries in other organs in that hypoxic and hypoperfused lung tissue develops increased vascular permeability and neutrophil infiltration after reexpansion. This study investigated the lung cellular glutathione system during hypoxia (produced by lung collapse) and after reoxygenation (produced by reexpansion). Two separate groups of rabbits were studied to determine effects of lung hypoxia-reoxygenation on 1) lung glutathione peroxidase and reductase enzyme activities and 2) lung tissue, plasma, and alveolar lavage fluid total (reduced glutathione plus glutathione disulfide) and oxidized glutathione. Neither lung collapse for 3-7 days nor reexpansion for 2 h after 7 days of collapse affected glutathione peroxidase [controls, 0.36 +/- 0.04 (left), 0.38 +/- 0.03 U/mg DNA (right)] or reductase [controls, 0.12 +/- 0.01 (left), 0.14 +/- 0.01 U/mg DNA (right)] activities. The concentration of glutathione disulfide increased markedly in right alveolar lavage fluid, but not in plasma, after right lung reexpansion. Right lung total glutathione decreased significantly (-19%) after 7 days of collapse. After right lung reexpansion, both left (-65%) and right (-68%) lung total glutathione decreased significantly. The percent of total glutathione present in the oxidized form increased significantly in both left (to 15.5 +/- 4.0% of total) and right (to 18.7 +/- 6.3% of total) lungs after reexpansion of the right lung. These data indicate that lung tissue hypoxia, produced by unilateral lung collapse, was associated with a unilateral decrease in lung total glutathione content. Right lung reoxygenation, due to rapid reexpansion, caused a bilateral decrease in lung total glutathione content and an increase in right lung and alveolar lavage fluid glutathione disulfide concentration.

Role of microvascular pressure in reactive oxygen-induced lung edema

1989 ◽  
Vol 66 (3) ◽  
pp. 1486-1493 ◽  
Author(s):  
J. W. Barnard ◽  
C. E. Patterson ◽  
M. T. Hull ◽  
W. W. Wagner ◽  
R. A. Rhoades
Keyword(s):  
Lung Injury ◽  
Xanthine Oxidase ◽  
Pressure Rise ◽  
Progressive Increase ◽  
Lung Edema ◽  
Fluid Loss ◽  
H2o2 Production ◽  
Edema Formation ◽  
Pulmonary Arterial ◽  
Protein Rich

O2 radicals are important in the pathogenesis of acute lung injury. The purpose of this investigation was to determine the role that microvascular pressure plays in edema induced by reactive O2 species generated by xanthine oxidase. In isolated rat lungs perfused with Krebs buffer plus 4% albumin, 5 mM glucose, and 2 mM xanthine at constant flow (13 ml/min), addition of xanthine oxidase (0.02 U/ml) caused a progressive increase in both pulmonary arterial and microvascular pressure (double occlusion method), which preceded the onset of edema. Both the pressure rise and edema formation were blocked by catalase, suggesting that vascular injury was related to H2O2 production. Lungs not exposed to free radicals that had microvascular pressure elevated to match that of the xanthine oxidase-perfused lungs showed only a small, reversible (nonedematous) weight gain. Lungs exposed to xanthine oxidase but perfused at constant microvascular pressure (5 Torr, similar to control lungs) showed a significant delay in protein-rich edema formation. These data indicate that reactive O2 metabolites induced lung injury, which is accompanied by increased microvascular pressure. Although the rise in microvascular pressure was shown not to be essential for edema formation, it does play a role in acceleration of the rate of transvascular fluid loss.

scholarly journals Attenuation of pulmonary injury by an inhaled MMP inhibitor in the endotoxin lung injury model

2020 ◽  
Vol 319 (6) ◽  
pp. L1036-L1047
Author(s):  
Adam Gerber ◽  
Monica Goldklang ◽  
Kyle Stearns ◽  
Xinran Ma ◽  
Rui Xiao ◽  
...  
Keyword(s):  
Lung Injury ◽  
Pulmonary Edema ◽  
Pulmonary Inflammation ◽  
Neutrophil Migration ◽  
Neutrophil Infiltration ◽  
Vascular Integrity ◽  
Pulmonary Vascular Permeability ◽  
Mmp Inhibitor ◽  
Cell Counts ◽  
Lung Injury Model

Acute respiratory distress syndrome (ARDS) is characterized by pulmonary edema and poor gas exchange resulting from severe inflammatory lung injury. Neutrophilic infiltration and increased pulmonary vascular permeability are hallmarks of early ARDS and precipitate a self-perpetuating cascade of inflammatory signaling. The biochemical processes initiating these events remain unclear. Typically associated with extracellular matrix degradation, recent data suggest matrix metalloproteinases (MMPs) are regulators of pulmonary inflammation. To demonstrate that inhalation of a broad MMP inhibitor attenuates LPS induced pulmonary inflammation. Nebulized CGS27023AM (CGS) was administered to LPS-injured mice. Pulmonary CGS levels were examined by mass spectroscopy. Inflammatory scoring of hematoxylin-eosin sections, examination of vascular integrity via lung wet/dry and bronchoalveolar lvage/serum FITC-albumin ratios were performed. Cleaved caspase-3 levels were also assessed. Differential cell counts and pulse-chase labeling were utilized to determine the effects of CGS on neutrophil migration. The effects of CGS on human neutrophil migration and viability were examined using Boyden chambers and MTT assays. Nebulization successfully delivered CGS to the lungs. Treatment decreased pulmonary inflammatory scores, edema, and apoptosis in LPS treated animals. Neutrophil chemotaxis was reduced by CGS treatment, with inhalation causing significant reductions in both the total number and newly produced bromodeoxyuridine-positive cells infiltrating the lung. Mechanistic studies on cells isolated from humans demonstrate that CGS-treated neutrophils exhibit decreased chemotaxis. The protective effect observed following treatment with a nonspecific MMP inhibitor indicates that one or more MMPs mediate the development of pulmonary edema and neutrophil infiltration in response to LPS injury. In accordance with this, inhaled MMP inhibitors warrant further study as a potential new therapeutic avenue for treatment of acute lung injury.

Reexpansion pulmonary edema

Nursing ◽  
2003 ◽  
Vol 33 (12) ◽  
pp. 96 ◽  
Author(s):  
DENISE D. HAYES
Keyword(s):  
Pulmonary Edema ◽  
Reexpansion Pulmonary Edema

scholarly journals Dexmedetomidine alleviates pulmonary edema through the epithelial sodium channel (ENaC) via the PI3K/Akt/Nedd4-2 pathway in LPS-induced acute lung injury

2021 ◽  
Author(s):  
Yuanxu Jiang ◽  
Mingzhu Xia ◽  
Jing Xu ◽  
Qiang Huang ◽  
Zhongliang Dai ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Sodium Channel ◽  
Pulmonary Edema ◽  
Cell Injury ◽  
A549 Cells ◽  
Alveolar Epithelial ◽  
Phosphorylated Akt ◽  
Epithelial Sodium Channel Enac

AbstractDexmedetomidine (Dex), a highly selective α2-adrenergic receptor (α2AR) agonist, has an anti-inflammatory property and can alleviate pulmonary edema in lipopolysaccharide (LPS)-induced acute lung injury (ALI), but the mechanism is still unclear. In this study, we attempted to investigate the effect of Dex on alveolar epithelial sodium channel (ENaC) in the modulation of alveolar fluid clearance (AFC) and the underlying mechanism. Lipopolysaccharide (LPS) was used to induce acute lung injury (ALI) in rats and alveolar epithelial cell injury in A549 cells. In vivo, Dex markedly reduced pulmonary edema induced by LPS through promoting AFC, prevented LPS-induced downregulation of α-, β-, and γ-ENaC expression, attenuated inflammatory cell infiltration in lung tissue, reduced the concentrations of TNF-α, IL-1β, and IL-6, and increased concentrations of IL-10 in bronchoalveolar lavage fluid (BALF). In A549 cells stimulated with LPS, Dex attenuated LPS-mediated cell injury and the downregulation of α-, β-, and γ-ENaC expression. However, all of these effects were blocked by the PI3K inhibitor LY294002, suggesting that the protective role of Dex is PI3K-dependent. Additionally, Dex increased the expression of phosphorylated Akt and reduced the expression of Nedd4-2, while LY294002 reversed the effect of Dex in vivo and in vitro. Furthermore, insulin-like growth factor (IGF)-1, a PI3K agonists, promoted the expression of phosphorylated Akt and reduced the expression of Nedd4-2 in LPS-stimulated A549 cells, indicating that Dex worked through PI3K, and Akt and Nedd4-2 are downstream of PI3K. In conclusion, Dex alleviates pulmonary edema by suppressing inflammatory response in LPS-induced ALI, and the mechanism is partly related to the upregulation of ENaC expression via the PI3K/Akt/Nedd4-2 signaling pathway.

scholarly journals Cigarette Smoke Exposure Worsens Endotoxin-Induced Lung Injury and Pulmonary Edema in Mice

2017 ◽  
Vol 19 (9) ◽  
pp. 1033-1039 ◽  
Author(s):  
Jeffrey E Gotts ◽  
Jason Abbott ◽  
Xiaohui Fang ◽  
Haru Yanagisawa ◽  
Naoki Takasaka ◽  
...  
Keyword(s):  
Lung Injury ◽  
Pulmonary Edema ◽  
Cigarette Smoke ◽  
Smoke Exposure ◽  
Cigarette Smoke Exposure

scholarly journals Claudin-4 augments alveolar epithelial barrier function and is induced in acute lung injury

2009 ◽  
Vol 297 (2) ◽  
pp. L219-L227 ◽  
Author(s):  
Charlie Wray ◽  
Ying Mao ◽  
Jue Pan ◽  
Anita Chandrasena ◽  
Frank Piasta ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Tight Junction ◽  
Pulmonary Edema ◽  
Barrier Function ◽  
Mapk Pathway ◽  
Paracellular Transport ◽  
Epithelial Barrier ◽  
Altered Expression ◽  
Alveolar Epithelial

Intact alveolar barrier function is associated with better outcomes in acute lung injury patients; however, the regulation of alveolar epithelial paracellular transport during lung injury has not been extensively investigated. This study was undertaken to determine whether changes in tight junction claudin expression affect alveolar epithelial barrier properties and to determine the mechanisms of altered expression. In anesthetized mice exposed to ventilator-induced lung injury, claudin-4 was specifically induced among tight junction structural proteins. Real-time PCR showed an eightfold increase in claudin-4 expression in the lung injury model. To examine the role of this protein in barrier regulation, claudin-4 function was inhibited with small interfering RNA (siRNA) and a blocking peptide derived from the binding domain of Clostridium perfringens enterotoxin (CPEBD). Inhibition of claudin-4 decreased transepithelial electrical resistance but did not alter macromolecule permeability in primary rat and human epithelial cells. In mice, CPEBD decreased air space fluid clearance >33% and resulted in pulmonary edema during moderate tidal volume ventilation that did not induce edema in control peptide-treated mice. In vitro phorbol ester induced a ninefold increase in claudin-4 expression that was dependent on PKC activation and the JNK MAPK pathway. These data establish that changes in alveolar epithelial claudin expression influence paracellular transport, alveolar fluid clearance rates, and susceptibility to pulmonary edema. We hypothesize that increased claudin-4 expression early in acute lung injury represents a mechanism to limit pulmonary edema and that the regulation of alveolar epithelial claudin expression may be a novel target for acute lung injury therapy.

Reexpansion Pulmonary Edema

CHEST Journal ◽  
2014 ◽  
Vol 145 (3) ◽  
pp. 25A
Author(s):  
Sebastian Peñafiel ◽  
Eugenia Libreros Niño ◽  
José González García
Keyword(s):  
Pulmonary Edema ◽  
Reexpansion Pulmonary Edema
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