Open AccessNOS2 regulation of LPS-induced airway inflammation via S-nitrosylation of NF-κB p65
Author(s) -
Zachary T. Kelleher,
Erin N. Potts,
Mulugu V. Brahmajothi,
Matthew W. Foster,
Richard L. Auten,
W. Michael Foster,
Hiram W. Marshall
Publication year - 2011
Publication title -
american journal of physiology. lung cellular and molecular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.892
H-Index - 163
eISSN - 1522-1504
pISSN - 1040-0605
DOI - 10.1152/ajplung.00463.2010
Subject(s) - respiratory epithelium , lipopolysaccharide , inflammation , nitric oxide , nf κb , lung , respiratory system , epithelium , respiratory tract , alveolar epithelium , nitric oxide synthase , immunology , chemistry , biology , medicine , pathology , endocrinology
Inducible nitric oxide synthase (NOS2) expression is increased in the airway epithelium in acute inflammatory disorders although the physiological impact remains unclear. We have previously shown that NOS2 inhibits NF-κB (p50-p65) activation in respiratory epithelial cells by inducing S-nitrosylation of the p65 monomer (SNO-p65). In addition, we have demonstrated that mouse lung SNO-p65 levels are acutely depleted in a lipopolysaccharide (LPS) model of lung injury and that augmenting SNO-p65 levels before LPS treatment results in decreased airway epithelial NF-κB activation, airway inflammation, and lung injury. We now show that aerosolized LPS induces NOS2 expression in the respiratory epithelium concomitant with an increase in lung SNO-p65 levels and a decrease in airway NF-κB activity. Genetic deletion of NOS2 results in an absence of SNO-p65 formation, persistent NF-κB activity in the respiratory epithelium, and prolonged airway inflammation. These results indicate that a primary function of LPS-induced NOS2 expression in the respiratory epithelium is to modulate the inflammatory response through deactivation of NF-κB via S-nitrosylation of p65, thereby counteracting the initial stimulus-coupled denitrosylation.