Role of NADPH oxidase in interleukin-4-induced monocyte chemoattractant protein-1 expression in vascular endothelium.
OBJECTIVE
The pro-oxidative and pro-inflammatory pathways in vascular endothelium have been implicated in the development of atherosclerosis. In the present study, we investigated effect of interleukin-4 (IL-4) on monocyte chemoattractant protein-1 (MCP-1) expression in vascular endothelium and examined the role of distinct sources of reactive oxygen species (ROS) in this process.


RESULTS
Real-time reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay showed that IL-4 significantly up-regulated mRNA and protein expression of MCP-1 in human aortic endothelial cells (HAEC) and C57BL/6 mice. A significant and dose-dependent inhibition of IL-4-induced MCP-1 expression was observed in HAEC pre-treated with antioxidants, such as pyrrolidine dithiocarbamate and epigallocatechin gallate, indicating that IL-4-induced MCP-1 expression is mediated via a ROS-dependent mechanism. Additionally, pharmacological inhibitors of NADPH oxidase (NOX) significantly attenuated IL-4-induced MCP-1 expression in HAEC. Furthermore, the disruption of the NOX gene dramatically reduced IL-4-induced MCP-1 expression in NOX knockout mice (B6.129S6-Cybb(tm1Din)/J). In contrast, overexpression of MCP-1 in IL-4-stimulated HAEC was not affected by inhibiting other ROS generating pathways, such as xanthine oxidase and the mitochondrial electron transport chain.


CONCLUSIONS
These results demonstrate that IL-4 up-regulates MCP-1 expression in vascular endothelium through NOX-mediated ROS generation.
Lee
Yong Woo
YW
Department of Biomedical Sciences and Pathobiology, School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA 24061, USA. ywlee@vt.edu
Lee
Won Hee
WH
Kim
Paul H
PH
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001011:Aorta / Q000187:drug effects / Q000201:enzymology; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism*; D006801:Humans; D015847:Interleukin-4 / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019255:NADPH Oxidases / Q000032:analysis / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
D000975:Antioxidants; D018932:Chemokine CCL2; D015847:Interleukin-4; D019255:NADPH Oxidases