scholarly journals Lipoxin A4prevents tight junction disruption and delays the colonization of cystic fibrosis bronchial epithelial cells byPseudomonas aeruginosa

2016 ◽  
Vol 310 (11) ◽  
pp. L1053-L1061 ◽  
Author(s):  
Gerard Higgins ◽  
Coral Fustero Torre ◽  
Jean Tyrrell ◽  
Paul McNally ◽  
Brian J. Harvey ◽  
...  

The specialized proresolution lipid mediator lipoxin A4(LXA4) is abnormally produced in cystic fibrosis (CF) airways. LXA4increases the CF airway surface liquid height and stimulates airway epithelial repair and tight junction formation. We report here a protective effect of LXA4(1 nM) against tight junction disruption caused by Pseudomonas aeruginosa bacterial challenge together with a delaying action against bacterial invasion in CF airway epithelial cells from patients with CF and immortalized cell lines. Bacterial invasion and tight junction integrity were measured by gentamicin exclusion assays and confocal fluorescence microscopy in non-CF (NuLi-1) and CF (CuFi-1) bronchial epithelial cell lines and in primary CF cultures, grown under an air/liquid interface, exposed to either a clinical or laboratory strains of P. aeruginosa. LXA4delayed P. aeruginosa invasion and transepithelial migration in CF and normal bronchial epithelial cell cultures. These protective effects of LXA4were inhibited by the ALX/FPR2 lipoxin receptor antagonist BOC-2. LXA4prevented the reduction in mRNA biosynthesis and protein abundance of the tight junction protein ZO-1 and reduced tight junction disruption induced by P. aeruginsosa inoculation. In conclusion, LXA4plays a protective role in bronchial epithelium by stimulating tight junction repair and by delaying and reducing the invasion of CF bronchial epithelial cells by P. aeruginsosa.

1998 ◽  
Vol 72 (11) ◽  
pp. 8904-8912 ◽  
Author(s):  
S. Teramoto ◽  
J. S. Bartlett ◽  
D. McCarty ◽  
X. Xiao ◽  
R. J. Samulski ◽  
...  

ABSTRACT Adeno-associated virus (AAV) vectors appear promising for use in gene therapy in cystic fibrosis (CF) patients, yet many features of AAV-mediated gene transfer to airway epithelial cells are not well understood. We compared the transduction efficiencies of AAV vectors and adenovirus (Ad) vectors in immortalized cell lines from CF patients and in nasal epithelial primary cultures from normal humans and CF patients. Similar dose-dependent relationships between the vector multiplicities of infection and the efficiencies of lacZgene transfer were observed. However, levels of transduction for both Ad and recombinant AAV (rAAV) were significantly lower in the airway epithelial cell than in the control cell lines HeLa and HEK 293. Transduction efficiencies differed among cultured epithelial cell types, with poorly differentiated cells transducing more efficiently than well-differentiated cells. A time-dependent increase in gene expression was observed after infection for both vectors. For Ad, but not for AAV, this increase was dependent on prolonged incubation of cells with the vector. Furthermore, for rAAV (but not for rAd), the delay in maximal transduction could be abrogated by wild-type Ad helper infection. Thus, although helper virus is not required for maximal transduction, it increases the kinetics by which this is achieved. Expression of Ad E4 open reading frame 6 or addition of either hydroxyurea or camptothecin resulted in increased AAV transduction, as previously demonstrated for nonairway cells (albeit to lower final levels), suggesting that second-strand synthesis may not be the sole cause of inefficient transduction. Finally, the efficiency of AAV-mediated ex vivo gene transfer to lung cells was similar to that previously described for Ad vectors in that transduction was limited to regions of epithelial injury and preferentially targeted basal-like cells. These studies address the primary factors influencing rAAV infection of human airway cells and should impact successful gene delivery in CF patients.


1998 ◽  
Vol 275 (2) ◽  
pp. L372-L378 ◽  
Author(s):  
Karissa K. Adkins ◽  
Tricia D. Levan ◽  
Roger L. Miesfeld ◽  
John W. Bloom

Inflammation plays a central role in the pathogenesis of asthma. Glucocorticoids are first-line anti-inflammatory therapy in the treatment of asthma and are effective inhibitors of inflammatory cytokines. Clinical data demonstrate that granulocyte-macrophage colony-stimulating factor (GM-CSF) production by airway epithelial cells may be an important target of inhaled glucocorticoid therapy. We examined the regulatory mechanisms of GM-CSF expression by interleukin-1β (IL-1β) and the synthetic glucocorticoid dexamethasone in the BEAS-2B human bronchial epithelial cell line. IL-1β stimulation resulted in a 15-fold induction of GM-CSF protein, which was associated with a corresponding 47-fold maximal induction of GM-CSF mRNA levels. Treatment with the transcriptional inhibitor actinomycin D before IL-1β stimulation completely abolished induction of GM-CSF mRNA, whereas incubation with cycloheximide had no effect. Taken together, these data demonstrate that IL-1β induction of GM-CSF is mediated through transcriptional mechanisms. Dexamethasone treatment of BEAS-2B cells produced an 80% inhibition of IL-1β-induced GM-CSF protein and a 51% inhibition of GM-CSF mRNA. GM-CSF mRNA was rapidly degraded in these cells, and dexamethasone treatment did not significantly affect this decay rate. We conclude that, in the BEAS-2B bronchial epithelial cell line, IL-1β induction and dexamethasone repression of GM-CSF expression are mediated predominantly through transcriptional mechanisms.


2011 ◽  
Vol 300 (3) ◽  
pp. L380-L390 ◽  
Author(s):  
Anna Tamanini ◽  
Monica Borgatti ◽  
Alessia Finotti ◽  
Laura Piccagli ◽  
Valentino Bezzerri ◽  
...  

Chronic inflammatory response in the airway tract of patients affected by cystic fibrosis is characterized by an excessive recruitment of neutrophils to the bronchial lumina, driven by the chemokine interleukin (IL)-8. We previously found that 5-methoxypsoralen reduces Pseudomonas aeruginosa -dependent IL-8 transcription in bronchial epithelial cell lines, with an IC50 of 10 μM (Nicolis E, Lampronti I, Dechecchi MC, Borgatti M, Tamanini A, Bezzerri V, Bianchi N, Mazzon M, Mancini I, Giri MG, Rizzotti P, Gambari R, Cabrini G. Int Immunopharmacol 9: 1411–1422, 2009). Here, we extended the investigation to analogs of 5-methoxypsoralen, and we found that the most potent effect is obtained with 4,6,4′-trimethylangelicin (TMA), which inhibits P. aeruginosa -dependent IL-8 transcription at nanomolar concentration in IB3–1, CuFi-1, CFBE41o−, and Calu-3 bronchial epithelial cell lines. Analysis of phosphoproteins involved in proinflammatory transmembrane signaling evidenced that TMA reduces the phosphorylation of ribosomal S6 kinase-1 and AKT2/3, which we found indeed involved in P. aeruginosa -dependent activation of IL-8 gene transcription by testing the effect of pharmacological inhibitors. In addition, we found a docking site of TMA into NF-κB by in silico analysis, whereas inhibition of the NF-κB/DNA interactions in vitro by EMSA was observed at high concentrations (10 mM TMA). To further understand whether NF-κB pathway should be considered a target of TMA, chromatin immunoprecipitation was performed, and we observed that TMA (100 nM) preincubated in whole living cells reduced the interaction of NF-κB with the promoter of IL-8 gene. These results suggest that TMA could inhibit IL-8 gene transcription mainly by intervening on driving the recruitment of activated transcription factors on IL-8 gene promoter, as demonstrated here for NF-κB. Although the complete understanding of the mechanism of action of TMA deserves further investigation, an activity of TMA on phosphorylating pathways was already demonstrated by our study. Finally, since psoralens have been shown to potentiate cystic fibrosis transmembrane conductance regulator (CFTR)-mediated chloride transport, TMA was tested and found to potentiate CFTR-dependent chloride efflux. In conclusion, TMA is a dual-acting compound reducing excessive IL-8 expression and potentiating CFTR function.


PLoS ONE ◽  
2014 ◽  
Vol 9 (6) ◽  
pp. e100621 ◽  
Author(s):  
Natalia Molenda ◽  
Katarina Urbanova ◽  
Nelly Weiser ◽  
Kristina Kusche-Vihrog ◽  
Dorothee Günzel ◽  
...  

2019 ◽  
Vol 20 (7) ◽  
pp. 1678 ◽  
Author(s):  
Yi-Chen Lee ◽  
Chun-Yu Lin ◽  
Yen-Hsu Chen ◽  
Wen-Chin Chiu ◽  
Yen-Yun Wang ◽  
...  

Acute lung injury (ALI) is a life-threatening syndrome characterized by acute and severe hypoxemic respiratory failure. Visfatin, which is known as an obesity-related cytokine with pro-inflammatory activities, plays a role in regulation of inflammatory cytokines. The mechanisms of ALI remain unclear in critically ill patients. Survival in ALI patients appear to be influenced by the stress generated by mechanical ventilation and by ALI-associated factors that initiate the inflammatory response. The objective for this study was to understand the mechanisms of how visfatin regulates inflammatory cytokines and promotes ALI. The expression of visfatin was evaluated in ALI patients and mouse sepsis models. Moreover, the underlying mechanisms were investigated using human bronchial epithelial cell lines, BEAS-2B and NL-20. An increase of serum visfatin was discovered in ALI patients compared to normal controls. Results from hematoxylin and eosin (H&E) and immunohistochemistry staining also showed that visfatin protein was upregulated in mouse sepsis models. Moreover, lipopolysaccharide (LPS) induced visfatin expression, activated the STAT3/NFκB pathway, and increased the expression of pro-inflammatory cytokines, including IL1-β, IL-6, and TNF-α in human bronchial epithelial cell lines NL-20 and BEAS-2B. Co-treatment of visfatin inhibitor FK866 reversed the activation of the STAT3/NFκB pathway and the increase of pro-inflammatory cytokines induced by LPS. Our study provides new evidence for the involvement of visfatin and down-stream events in acute lung injury. Further studies are required to confirm whether the anti-visfatin approaches can improve ALI patient survival by alleviating the pro-inflammatory process.


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