Phosphodiesterase expression in human epithelial cells

1998 ◽  
Vol 275 (4) ◽  
pp. L694-L700 ◽  
Author(s):  
Lyndon C. Wright ◽  
Joachim Seybold ◽  
Annette Robichaud ◽  
Ian M. Adcock ◽  
Peter J. Barnes
Keyword(s):  
Epithelial Cells ◽  
Cell Function ◽  
Critical Role ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Epithelial Cell Line ◽  
Airway Epithelial ◽  
Bioactive Lipids ◽  
Rt Pcr ◽  
Inflammatory Conditions

Epithelial cells play a critical role in airway inflammation and have the capacity to produce many inflammatory mediators, including bioactive lipids and proinflammatory cytokines. Intracellular levels of cAMP and cGMP are important in the control of inflammatory cell function. These cyclic nucleotides are inactivated via a family of phosphodiesterase (PDE) enzymes, providing a possible site for drug intervention in chronic inflammatory conditions. We studied the expression of PDE activity in an epithelial cell line (A549) and in primary human airway epithelial cells (HAECs). We measured PDE function using specific inhibitors to identify the PDE families present and used RT-PCR to elucidate the expression of PDE isogenes. Both A549 cells and HAECs predominantly expressed PDE4 activity, with lesser PDE1, PDE3, and PDE5 activity. RT-PCR identified HSPDE4A5 and HSPDE4D3 together with HSPDE7. Inhibition of PDE4 and PDE3 reduced secretion by these cells. Epithelial PDE may be an important target for PDE4 inhibitors in the development of the control of asthmatic inflammation, particularly when delivered via the inhaled route.

Effect of defensins on interleukin-8 synthesis in airway epithelial cells

1997 ◽  
Vol 272 (5) ◽  
pp. L888-L896 ◽  
Author(s):  
S. Van Wetering ◽  
S. P. Mannesse-Lazeroms ◽  
M. A. Van Sterkenburg ◽  
M. R. Daha ◽  
J. H. Dijkman ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Neutrophil Elastase ◽  
Proteinase Inhibitor ◽  
De Novo ◽  
Tissue Injury ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Epithelial Cell Line ◽  
Mrna Levels ◽  
Airway Epithelial

Neutrophils play an important role in inflammatory processes in the lung and may cause tissue injury through, for example, release of proteinases such as neutrophil elastase. In addition to neutrophil elastase, stimulated neutrophils also release small nonenzymatic and cationic polypeptides termed defensins. The aim of the present study was to investigate whether defensins induce interleukin (IL)-8 expression in cells of the A549 lung epithelial cell line and in human primary bronchial epithelial cells (PBEC). Supernatants of defensin-treated A549 cells contained increased neutrophil chemotactic activity (16-fold) that was inhibited by antibodies against IL-8. Concurrently, within 3 and 6 h, defensins significantly increased the IL-8 levels in supernatants of both A549 cells (n = 6, P < 0.05 and P < 0.01, respectively) and PBEC (n = 4, P < 0.001 and P < 0.001, respectively). This defensin-induced increase was fully inhibited by the serine proteinase inhibitor alpha 1-proteinase inhibitor. In addition, defensins also increased IL-8 mRNA levels (12-fold); this increase was dependent on de novo mRNA synthesis and did not require protein synthesis. Furthermore, defensins did not affect IL-8 mRNA stability, indicating that the enhanced IL-8 expression was due to increased transcription. Our findings suggest that defensins, released by stimulated neutrophils, stimulate IL-8 synthesis by airway epithelial cells and thus may mediate the recruitment of additional neutrophils into the airways.

scholarly journals Anti-Inflammatory Properties of Fructo-Oligosaccharides in a Calf Lung Infection Model and in Mannheimia haemolytica-Infected Airway Epithelial Cells

Nutrients ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 3514
Author(s):  
Yang Cai ◽  
Myrthe S. Gilbert ◽  
Walter J. J. Gerrits ◽  
Gert Folkerts ◽  
Saskia Braber
Keyword(s):  
Epithelial Cells ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Mannheimia Haemolytica ◽  
Epithelial Barrier ◽  
Infection Model ◽  
Airway Epithelial ◽  
Clinical Scores ◽  
Lung Infections ◽  
Anti Inflammatory

Emerging antimicrobial-resistant pathogens highlight the importance of developing novel interventions. Here, we investigated the anti-inflammatory properties of Fructo-oligosaccharides (FOS) in calf lung infections and in airway epithelial cells stimulated with pathogens, and/or bacterial components. During a natural exposure, 100 male calves were fed milk replacer with or without FOS for 8 weeks. Then, immune parameters and cytokine/chemokine levels in the bronchoalveolar lavage fluid (BALF) and blood were measured, and clinical scores were investigated. Calf primary bronchial epithelial cells (PBECs) and human airway epithelial cells (A549) were treated with Mannheimia haemolytica, lipopolysaccharides (LPS), and/or flagellin, with or without FOS pretreatment. Thereafter, the cytokine/chemokine levels and epithelial barrier function were examined. Relative to the control (naturally occurring lung infections), FOS-fed calves had greater macrophage numbers in BALF and lower interleukin (IL)-8, IL-6, and IL-1β concentrations in the BALF and blood. However, FOS did not affect the clinical scores. At slaughter, FOS-fed calves had a lower severity of lung lesions compared to the control. Ex vivo, FOS prevented M. haemolytica-induced epithelial barrier dysfunction. Moreover, FOS reduced M. haemolytica- and flagellin-induced (but not LPS-induced) IL-8, TNF-α, and IL-6 release in PBECs and A549 cells. Overall, FOS had anti-inflammatory properties during the natural incidence of lung infections but had no effects on clinical symptoms.

scholarly journals FOXO3a regulates rhinovirus-induced innate immune responses in airway epithelial cells

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Joao Gimenes-Junior ◽  
Nicole Owuar ◽  
Hymavathi Reddy Vari ◽  
Wuyan Li ◽  
Nathaniel Xander ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Lung Inflammation ◽  
Inflammatory Cytokine ◽  
Airway Epithelial Cell ◽  
Critical Role ◽  
Airway Epithelial Cells ◽  
Type I ◽  
Airway Epithelial ◽  
Antiviral Responses

AbstractForkhead transcription factor class O (FOXO)3a, which plays a critical role in a wide variety of cellular processes, was also found to regulate cell-type-specific antiviral responses. Airway epithelial cells express FOXO3a and play an important role in clearing rhinovirus (RV) by mounting antiviral type I and type III interferon (IFN) responses. To elucidate the role of FOXO3a in regulating antiviral responses, we generated airway epithelial cell-specific Foxo3a knockout (Scga1b1-Foxo3a−/−) mice and a stable FOXO3a knockout human airway epithelial cell line. Compared to wild-type, Scga1b1-Foxo3a−/− mice show reduced IFN-α, IFN-β, IFN-λ2/3 in response to challenge with RV or double-stranded (ds)RNA mimic, Poly Inosinic-polycytidylic acid (Poly I:C) indicating defective dsRNA receptor signaling. RV-infected Scga1b1-Foxo3a−/− mice also show viral persistence, enhanced lung inflammation and elevated pro-inflammatory cytokine levels. FOXO3a K/O airway epithelial cells show attenuated IFN responses to RV infection and this was associated with conformational change in mitochondrial antiviral signaling protein (MAVS) but not with a reduction in the expression of dsRNA receptors under unstimulated conditions. Pretreatment with MitoTEMPO, a mitochondrial-specific antioxidant corrects MAVS conformation and restores antiviral IFN responses to subsequent RV infection in FOXO3a K/O cells. Inhibition of oxidative stress also reduces pro-inflammatory cytokine responses to RV in FOXO3a K/O cells. Together, our results indicate that FOXO3a plays a critical role in regulating antiviral responses as well as limiting pro-inflammatory cytokine expression. Based on these results, we conclude that FOXO3a contributes to optimal viral clearance and prevents excessive lung inflammation following RV infection.

Pseudomonaspyocyanine alters calcium signaling in human airway epithelial cells

1998 ◽  
Vol 274 (6) ◽  
pp. L893-L900 ◽  
Author(s):  
Gerene M. Denning ◽  
Michelle A. Railsback ◽  
George T. Rasmussen ◽  
Charles D. Cox ◽  
Bradley E. Britigan
Keyword(s):  
Epithelial Cells ◽  
Lung Disease ◽  
Cell Function ◽  
Oxidant Stress ◽  
Beat Frequency ◽  
Ciliary Beat Frequency ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Human Airway ◽  
Human Airway Epithelial Cells

Pseudomonas aeruginosa, an opportunistic human pathogen, causes both acute and chronic lung disease. P. aeruginosa exerts many of its pathophysiological effects by secreting virulence factors, including pyocyanine, a redox-active compound that increases intracellular oxidant stress. Because oxidant stress has been shown to affect cytosolic Ca2+concentration ([Ca2+]c) in other cell types, we studied the effect of pyocyanine on [Ca2+]cin human airway epithelial cells (A549 and HBE). At lower concentrations, pyocyanine inhibits inositol 1,4,5-trisphosphate formation and [Ca2+]cincreases in response to G protein-coupled receptor agonists. Conversely, at higher concentrations, pyocyanine itself increases [Ca2+]c. The pyocyanine-dependent [Ca2+]cincrease appears to be oxidant dependent and to result from increased inositol trisphosphate and release of Ca2+from intracellular stores. Ca2+plays a central role in epithelial cell function, including regulation of ion transport, mucus secretion, and ciliary beat frequency. By disrupting Ca2+homeostasis, pyocyanine could interfere with these critical functions and contribute to the pathophysiological effects observed in Pseudomonas-associated lung disease.

Pseudomonas aeruginosapyocyanin directly oxidizes glutathione and decreases its levels in airway epithelial cells

2004 ◽  
Vol 287 (1) ◽  
pp. L94-L103 ◽  
Author(s):  
Yunxia Q. O'Malley ◽  
Krzysztof J. Reszka ◽  
Douglas R. Spitz ◽  
Gerene M. Denning ◽  
Bradley E. Britigan
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Culture Media ◽  
Alveolar Epithelial Cell ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Alternative Source ◽  
Cell Functions

Production of pyocyanin enhances Pseudomonas aeruginosa virulence. Many of pyocyanin's in vitro and in vivo cytotoxic effects on human cells appear to result from its ability to redox cycle. Pyocyanin directly accepts electrons from NADH or NADPH with subsequent electron transfer to oxygen, generating reactive oxygen species. Reduced glutathione (GSH) is an important cellular antioxidant, and it contributes to the regulation of redox-sensitive signaling systems. Using the human bronchial epithelial (HBE) and the A549 human type II alveolar epithelial cell lines, we tested the hypothesis that pyocyanin can deplete airway epithelial cells of GSH. Incubation of both cell types with pyocyanin led to a concentration-dependent loss of cellular GSH (up to 50%) and an increase in oxidized GSH (GSSG) in the HBE, but not A549 cells, at 24 h. An increase in total GSH, mostly as GSSG, was detected in the culture media, suggesting export of GSH or GSSG from the pyocyanin-exposed cells. Loss of GSH could be due to pyocyanin-induced H2O2formation. However, overexpression of catalase only partially prevented the pyocyanin-mediated decline in cellular GSH. Cell-free electron paramagnetic resonance studies revealed that pyocyanin directly oxidizes GSH, forming pyocyanin free radical and O2−·. Pyocyanin oxidized other thiol-containing compounds, cysteine and N-acetyl-cysteine, but not methionine. Thus GSH may enhance pyocyanin-induced cytotoxicity by functioning as an alternative source of reducing equivalents for pyocyanin redox cycling. Pyocyanin-mediated alterations in cellular GSH may alter epithelial cell functions by modulating redox sensitive signaling events.

Anti-inflammatory effects of resveratrol in lung epithelial cells: molecular mechanisms

2004 ◽  
Vol 287 (4) ◽  
pp. L774-L783 ◽  
Author(s):  
Louise E. Donnelly ◽  
Robert Newton ◽  
Gina E. Kennedy ◽  
Peter S. Fenwick ◽  
Rachel H. F. Leung ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Colony Stimulating Factor ◽  
Macrophage Colony Stimulating Factor ◽  
Anti Inflammatory ◽  
Macrophage Colony ◽  
Stimulating Factor ◽  
Factor Release

Resveratrol (3,4′,5-trihydroxystilbene) is a polyphenolic stilbene found in the skins of red fruits, including grapes, that may be responsible for some of the health benefits ascribed to consumption of red wine. Resveratrol has been shown to have antioxidant properties and can act as an estrogen agonist. This study examined the anti-inflammatory effects of resveratrol on human airway epithelial cells. Resveratrol and the related molecule quercetin, but not deoxyrhapontin, inhibited IL-8 and granulocyte-macrophage colony-stimulating factor release from A549 cells. Neither the estrogen receptor antagonist tamoxifen nor the glucocorticoid antagonist mifepristone altered the inhibitory effect of resveratrol. The mechanism of resveratrol action was investigated further using luciferase reporter genes stably transfected into A549 cells. Resveratrol and quercetin inhibited NF-κB-, activator protein-1-, and cAMP response element binding protein-dependent transcription to a greater extent than the glucocorticosteroid dexamethasone. These compounds also had no significant effect on acetylation or deacetylation of core histones. Resveratrol, but not estradiol or N-acetyl cysteine, inhibited cytokine-stimulated inducible nitric oxide synthase expression and nitrite production (IC50 = 3.6 ± 2.9 μM) in human primary airway epithelial cells. Resveratrol also inhibited granulocyte-macrophage colony-stimulating factor release (IC50 = 0.44 ± 0.17 μM), IL-8 release (IC50 = 4.7 ± 3.3 μM), and cyclooxygenase-2 expression in these cells. This study demonstrates that resveratrol and quercetin have novel nonsteroidal anti-inflammatory activity that may have applications for the treatment of inflammatory diseases.

Bradykinin increases IL-8 generation in airway epithelial cells via COX-2-derived prostanoids

2002 ◽  
Vol 283 (3) ◽  
pp. L612-L618 ◽  
Author(s):  
Helen C. Rodgers ◽  
Linhua Pang ◽  
Elaine Holland ◽  
Lisa Corbett ◽  
Simon Range ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Epithelial Cells ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Prostaglandin E ◽  
Airway Epithelial ◽  
Neutrophilic Inflammation ◽  
Airway Diseases ◽  
Cox Inhibitor ◽  
Cox 2

Interleukin (IL)-8, the C-X-C chemokine, is a potent neutrophil chemoattractant that has been implicated in a number of inflammatory airway diseases such as cystic fibrosis. Here we tested the hypothesis that bradykinin, an inflammatory mediator and chloride secretagogue, would increase IL-8 generation in airway epithelial cells through autocrine generation of endogenous prostanoids. Bradykinin increased IL-8 generation in both a non-cystic fibrosis (A549) and cystic fibrosis epithelial cell line (CFTE29[Formula: see text]) that was inhibited by the nonselective cyclooxygenase (COX) inhibitor indomethacin and the COX-2 selective inhibitor NS-398. COX-2 was the only isoform of COX expressed in both cell lines. Furthermore, the COX substrate arachidonic acid and exogenous prostaglandin E2 both increased IL-8 release in A549 cells. These results suggest that bradykinin may contribute to neutrophilic inflammation in the airway by generation of IL-8 from airway epithelial cells. The dependence of this response on endogenous production of prostanoids by COX-2 suggests that selective COX-2 inhibitors may have a role in the treatment of airway diseases characterized by neutrophilic inflammation such as cystic fibrosis or chronic obstructive pulmonary disease.

scholarly journals Expression/Activation of PAR-1 in Airway Epithelial Cells of COPD Patients: Ex Vivo/In Vitro Study

2021 ◽  
Vol 22 (19) ◽  
pp. 10703
Author(s):  
Angela Marina Montalbano ◽  
Giuseppina Chiappara ◽  
Giusy Daniela Albano ◽  
Maria Ferraro ◽  
Caterina Di Sano ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Ex Vivo ◽  
In Vitro Study ◽  
Bronchial Epithelial Cell ◽  
Airway Epithelial Cells ◽  
Epithelial Cell Line ◽  
Airway Epithelial ◽  
Bronchial Epithelial ◽  
Copd Patients

The role of PAR-1 expression and activation was described in epithelial cells from the central and distal airways of COPD patients using an ex vivo/in vitro model. PAR-1 immunoreactivity was studied in epithelial cells from surgical specimens of the central and distal airways of COPD patients and healthy control (HC). Furthermore, PAR-1 expression and activation were measured in both the human bronchial epithelial cell line (16HBE) and normal human bronchial epithelial cells (NHBEs) exposed to cigarette smoke extract (CSE) (10%) or thrombin. Finally, cell proliferation, apoptosis, and IL-8 release were detected in stimulated NHBEs. We identified higher levels of PAR-1 expression/activation in epithelial cells from the central airways of COPD patients than in HC. Active PAR-1 increased in epithelial cells from central and distal airways of COPD, with higher levels in COPD smokers (correlated with pack-years) than in COPD ex-smokers. 16HBE and NHBEs exposed to CSE or thrombin showed increased levels of active PAR-1 (localized in the cytoplasm) than baseline conditions, while NHBEs treated with thrombin or CSE showed increased levels of IL-8 proteins, with an additional effect when used in combination. Smoking habits generate the upregulation of PAR-1 expression/activation in airway epithelial cells, and promoting IL-8 release might affect the recruitment of infiltrating cells in the airways of COPD patients.

scholarly journals Flagellin from Pseudomonas aeruginosa modulates SARS-CoV-2 infectivity in CF airway epithelial cells by increasing TMPRSS2 expression

2020 ◽  
Author(s):  
Manon Ruffin ◽  
Jeanne Bigot ◽  
Claire Calmel ◽  
Julia Mercier ◽  
Andrés Pizzorno ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Respiratory Diseases ◽  
Critical Role ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Health Crisis ◽  
Chronic Respiratory Diseases ◽  
Major Significance ◽  
Main Component ◽  
Health Situation

AbstractThe major challenge of the COVID-19 health crisis is to identify the factors of susceptibility to SARS-Cov2 in order to adapt the recommendations to the populations and to reduce the risk of getting COVID-19 to the most vulnerable people especially those having chronic respiratory diseases including cystic fibrosis (CF). Airway epithelial cells (AEC) are playing a critical role in the immune response and in COVID-19 severity. SARS-CoV-2 infects the airways through ACE2 receptor and the host protease TMPRSS2 was shown to play a major role in SARS-CoV-2 infectivity. Here, we show that the main component of P. aeruginosa flagella, ie. flagellin is able to increase TMPRSS2 expression in AEC, and even more in those deficient for CFTR. Importantly, this increased TMPRSS2 expression is associated with an increase in the level of SARS-CoV-2 infection. Considering the urgency of the health situation, this result is of major significance for patients with CF which are frequently infected and colonized by P. aeruginosa during the course of the disease.

scholarly journals Flagellin From Pseudomonas aeruginosa Modulates SARS-CoV-2 Infectivity in Cystic Fibrosis Airway Epithelial Cells by Increasing TMPRSS2 Expression

2021 ◽  
Vol 12 ◽  
Author(s):  
Manon Ruffin ◽  
Jeanne Bigot ◽  
Claire Calmel ◽  
Julia Mercier ◽  
Maëlle Givelet ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Epithelial Cells ◽  
Critical Role ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Health Crisis ◽  
Chronic Respiratory Diseases ◽  
Cf Transmembrane Conductance Regulator ◽  
Main Component

In the coronavirus disease 2019 (COVID-19) health crisis, one major challenge is to identify the susceptibility factors of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in order to adapt the recommendations for populations, as well as to reduce the risk of COVID-19 development in the most vulnerable people, especially patients with chronic respiratory diseases such as cystic fibrosis (CF). Airway epithelial cells (AECs) play a critical role in the modulation of both immune responses and COVID-19 severity. SARS-CoV-2 infects the airway through the receptor angiotensin-converting enzyme 2, and a host protease, transmembrane serine protease 2 (TMPRSS2), plays a major role in SARS-CoV-2 infectivity. Here, we show that Pseudomonas aeruginosa increases TMPRSS2 expression, notably in primary AECs with deficiency of the ion channel CF transmembrane conductance regulator (CFTR). Further, we show that the main component of P. aeruginosa flagella, the protein flagellin, increases TMPRSS2 expression in primary AECs and Calu-3 cells, through activation of Toll-like receptor-5 and p38 MAPK. This increase is particularly seen in Calu-3 cells deficient for CFTR and is associated with an intracellular increased level of SARS-CoV-2 infection, however, with no effect on the amount of virus particles released. Considering the urgency of the COVID-19 health crisis, this result may be of clinical significance for CF patients, who are frequently infected with and colonized by P. aeruginosa during the course of CF and might develop COVID-19.

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