Research Article Krüppel-Like Factor 5 Mediates Proinflammatory Cytokine Expression in Lipopolysaccharide-Induced Acute Lung Injury through Upregulation of Nuclear Factor-

Copyright © 2014 Hsiu-Lin Chen et al.This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Acute lung injury (ALI) is associated with an inflammation-mediated process, and the transcription factor, Krüppel-like factor 5 (KLF5), might play a crucial role in inflammatory lung disease. In this study, we evaluated KLF5, reactive oxygen species (ROS), and inflammatory responses in a lipopolysaccharide- (LPS-) inducedALImodel to elucidate the role of KLF5 inALI. Our data indicated that LPS upregulates proinflammatory cytokine expression in human bronchial epithelial cells in a dose-dependent manner. We observed upregulated KLF5 protein expression in human bronchial epithelial cells exposed to LPS, with peak expression 1 h after LPS treatment, and subsequent upregulation of p65 protein expression and p65 phosphorylation at Ser276. These results indicate that KLF5 mediates proinflammatory cytokine expression by upregulating nuclear factor-kappaB (NF