TGF-ß3 Induces Autophagic Activity by Increasing ROS Generation in a NOX4-Dependent Pathway.
Mediators Inflamm
; 2019: 3153240, 2019.
Article
em En
| MEDLINE
| ID: mdl-32082074
ABSTRACT
Higher concentrations of reactive oxygen species (ROS) have been associated with epithelial cell damage, cell shedding, and airway hyperresponsiveness. Previous studies have indicated that transforming growth factor-beta (TGF-ß) mediates ROS production and NADPH oxidase (NOX) activity. In our previous study, we also observed that TGF-ß3 increases mucus secretion in airway epithelial cells in an autophagy-dependent fashion. Although it is well known that the relationship between ROS and autophagy is cell context-dependent, the exact mechanism of action remains unclear. The following study examined whether ROS act as upstream of autophagy activation in response to TGF-ß3 induction. Using an allergic inflammation mouse model induced by house dust mite (HDM), we observed elevated lung amounts of TGF-ß3 accompanied by increased ROS levels. And we found that ROS levels were elevated and NOX4 expression was increased in TGF-ß3-induced epithelial cells, while the lack of NOX4 in the epithelial cells could reduce ROS generation and autophagy-dependent MUC5AC expression treated with TGF-ß3. Furthermore, our studies demonstrated that the Smad2/3 pathway was involved in TGF-ß3-induced ROS generation by promoting NOX4 expression. The inhibition of ROS generation by N-Acetyl-L-cysteine (NAC) resulted in a decrease in mucus expression and autophagy activity in vivo as well as in vitro. Finally, TGF-ß3-neutralizing antibody significantly reduced the ROS generation, mucus expression, and autophagy activity and also decreased the phosphorylation of Smad2 and Smad3. Taken together, the obtained results revealed that persistent TGF-ß3 activation increased ROS levels in a NOX4-dependent pathway and subsequently induced autophagy as well as MUC5AC expression in the epithelial cells.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Autofagia
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Espécies Reativas de Oxigênio
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Fator de Crescimento Transformador beta3
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NADPH Oxidase 4
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Female
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Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article