Published ahead of print on October 3, 2003, doi:10.1165/rcmb.2003-0056OC
© 2004 American Thoracic Society DOI: 10.1165/rcmb.2003-0056OC Airway Epithelial Integrity Is Protected by a Long-Acting ß2-Adrenergic Receptor AgonistINSERM UMRS 514 and EA 2070, IFR 53, Laboratoire de Pharmacologie, Centre Hospitalier Universitaire Maison Blanche, Reims, France Address correspondence to: Edith Puchelle, UMRS INSERM 514, Hôpital Maison Blanche, 45, rue Cognacq Jay, 51092 Reims Cedex, France. E-mail: edith.puchelle{at}univ-reims.fr Airway epithelial integrity may be impaired by bacterial exoproducts, which are able to degrade tight junction–associated proteins such as zonula occludens 1 (ZO-1). We have investigated the protective effect of salmeterol, a long-acting ß2-adrenergic agonist, on Pseudomonas aeruginosa–induced alteration of the epithelial junctional barrier. We demonstrate in human airway epithelial cells (HAEC) that salmeterol induces a time-dependent increase in ZO-1 protein, although no significant change in ZO-1 transcripts was observed. When HAEC cultures were exposed to P. aeruginosa (PAO1) supernatants, apical expression of ZO-1 protein was maintained in salmeterol-pretreated HAEC cultures, whereas it disappeared after PAO1 exposure in cultures not pretreated with salmeterol. Western blot experiments showed that the 220-kD ZO-1 protein was decreased after PAO1 incubation but was still present in salmeterol-pretreated HAEC extracts. The functional activity of ZO-1 protein was monitored by measuring transepithelial resistance and analyzing the diffusion of a low molecular weight tracer through the intercellular spaces. After PAO1 incubation, the epithelial integrity of HAEC was impaired, as shown by a decrease in transepithelial resistance and increased paracellular permeability, but was not significantly altered after salmeterol preincubation. These results demonstrate that salmeterol may contribute to the protection of the airway epithelium barrier against bacterial virulence factors.
Abbreviations: ß2-receptor agonist, ß2-RA • cyclic AMP, cAMP • cystic fibrosis, CF • colony-forming unit, cfu • chronic obstructive pulmonary disease, COPD • glyceraldehyde-3-phosphate dehydrogenase, GAPDH • human airway epithelial cells, HAEC • N-2-hydroxyethylpiperazine-N'-2-ethane sulfonic acid, HEPES • matrix metalloproteinase, MMP • phosphate-buffered saline, PBS • sodium dodecyl sulfate, SDS • transepithelial resistance, TER • tight junction, TJ • Trypticase Soy Broth, TSB • zonula occludens 1, ZO-1 This article has been cited by other articles:
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