학술논문

Activation of Transcription Factor Nrf2 Signalling by the Sphingosine Kinase Inhibitor SKI-II Is Mediated by the Formation of Keap1 Dimers.
Document Type
Article
Source
PLoS ONE. Feb2014, Vol. 9 Issue 2, p1-11. 11p.
Subject
*TRANSCRIPTION factors
*NF-kappa B
*CELLULAR signal transduction
*SPHINGOSINE kinase
*ENZYME inhibitors
*KEAP1 (Protein)
*ANTIOXIDANTS
Language
ISSN
1932-6203
Abstract
Background: Anti-oxidant capacity is crucial defence against environmental or endogenous oxidative stress. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a redox-sensitive transcription factor that plays a key defensive role against oxidative and cytotoxic stress and cellular senescence. However, Nrf2 signalling is impaired in several aging-related diseases, such as chronic pulmonary obstructive disease (COPD), cancer, and neurodegenerative diseases. Thus, novel therapeutics that enhance Nrf2 signalling are an attractive approach to treat these diseases. Methodology/Principal Findings: Nrf2 was stabilized by SKI-II (2-(p-hydroxyanilino)-4-(p-chlorophenyl) thiazole), which is a known sphingosine kinase inhibitor, in human bronchial epithelial cell line, BEAS2B, and in primary human bronchial epithelial cells, leading to enhancement of anti-oxidant proteins, such as HO-1, NQO1 and GCLM. The activation of Nrf2 was achieved by the generation of inactive dimerized form of Keap1, a negative regulator of Nrf2 expression, which was independent of sphingosine kinase inhibition. Using mice that were exposed to cigarette smoke, SKI-II induced Nrf2 expression together with HO-1 in their lungs. In addition, SKI-II reduced cigarette smoke mediated oxidative stress, macrophages and neutrophil infiltration and markers of inflammation in mice. Conclusions/Significance: SKI-II appears to be a novel activator of Nrf2 signalling via the inactivation of Keap1. [ABSTRACT FROM AUTHOR]