Pseudomonas aeruginosa Homoserine lactone activates store-operated cAMP and cystic fibrosis transmembrane regulator-dependent Cl- secretion by human airway epithelia.
J Biol Chem
; 285(45): 34850-63, 2010 Nov 05.
Article
em En
| MEDLINE
| ID: mdl-20739289
ABSTRACT
The ubiquitous bacterium Pseudomonas aeruginosa frequently causes hospital-acquired infections. P. aeruginosa also infects the lungs of cystic fibrosis (CF) patients and secretes N-(3-oxo-dodecanoyl)-S-homoserine lactone (3O-C12) to regulate bacterial gene expression critical for P. aeruginosa persistence. In addition to its effects as a quorum-sensing gene regulator in P. aeruginosa, 3O-C12 elicits cross-kingdom effects on host cell signaling leading to both pro- or anti-inflammatory effects. We find that in addition to these slow effects mediated through changes in gene expression, 3O-C12 also rapidly increases Cl(-) and fluid secretion in the cystic fibrosis transmembrane regulator (CFTR)-expressing airway epithelia. 3O-C12 does not stimulate Cl(-) secretion in CF cells, suggesting that lactone activates the CFTR. 3O-C12 also appears to directly activate the inositol trisphosphate receptor and release Ca(2+) from the endoplasmic reticulum (ER), lowering [Ca(2+)] in the ER and thereby activating the Ca(2+)-sensitive ER signaling protein STIM1. 3O-C12 increases cytosolic [Ca(2+)] and, strikingly, also cytosolic [cAMP], the known activator of CFTR. Activation of Cl(-) current by 3O-C12 was inhibited by a cAMP antagonist and increased by a phosphodiesterase inhibitor. Finally, a Ca(2+) buffer that lowers [Ca(2+)] in the ER similar to the effect of 3O-C12 also increased cAMP and I(Cl). The results suggest that 3O-C12 stimulates CFTR-dependent Cl(-) and fluid secretion in airway epithelial cells by activating the inositol trisphosphate receptor, thus lowering [Ca(2+)] in the ER and activating STIM1 and store-operated cAMP production. In CF airways, where CFTR is absent, the adaptive ability to rapidly flush the bacteria away is compromised because the lactone cannot affect Cl(-) and fluid secretion.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pseudomonas aeruginosa
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Infecções por Pseudomonas
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4-Butirolactona
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Cloretos
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AMP Cíclico
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Regulador de Condutância Transmembrana em Fibrose Cística
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Mucosa Respiratória
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Retículo Endoplasmático
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Proteínas de Membrana
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Proteínas de Neoplasias
Limite:
Humans
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos