Glycogen synthase kinase-3ß modulation of glucocorticoid responsiveness in COPD.
Am J Physiol Lung Cell Mol Physiol
; 309(10): L1112-23, 2015 Nov 15.
Article
em En
| MEDLINE
| ID: mdl-26320152
ABSTRACT
In chronic obstructive pulmonary disease (COPD), oxidative stress regulates the inflammatory response of bronchial epithelium and monocytes/macrophages through kinase modulation and has been linked to glucocorticoid unresponsiveness. Glycogen synthase-3ß (GSK3ß) inactivation plays a key role in mediating signaling processes upon reactive oxygen species (ROS) exposure. We hypothesized that GSK3ß is involved in oxidative stress-induced glucocorticoid insensitivity in COPD. We studied levels of phospho-GSK3ß-Ser9, a marker of GSK3ß inactivation, in lung sections and cultured monocytes and bronchial epithelial cells of COPD patients, control smokers, and nonsmokers. We observed increased levels of phospho-GSK3ß-Ser9 in monocytes, alveolar macrophages, and bronchial epithelial cells from COPD patients and control smokers compared with nonsmokers. Pharmacological inactivation of GSK3ß did not affect CXCL8 or granulocyte-macrophage colony-stimulating factor (GM-CSF) expression but resulted in glucocorticoid insensitivity in vitro in both inflammatory and structural cells. Further mechanistic studies in monocyte and bronchial epithelial cell lines showed that GSK3ß inactivation is a common effector of oxidative stress-induced activation of the MEK/ERK-1/2 and phosphatidylinositol 3-kinase/Akt signaling pathways leading to glucocorticoid unresponsiveness. In primary monocytes, the mechanism involved modulation of histone deacetylase 2 (HDAC2) activity in response to GSK3ß inactivation. In conclusion, we demonstrate for the first time that ROS-induced glucocorticoid unresponsiveness in COPD is mediated through GSK3ß, acting as a ROS-sensitive hub.
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Assunto principal:
Dexametasona
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Doença Pulmonar Obstrutiva Crônica
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Quinase 3 da Glicogênio Sintase
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Glucocorticoides
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article