Item Type: | Article |
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Title: | Pivotal role of protein kinase C(δ) in angiotensin II-induced endothelial cyclooxygenase-2 expression: a link to vascular inflammation |
Creators Name: | Wong, S.L., Lau, C.W., Wong, W.T., Xu, A., Au, C.L., Ng, C.F., Ng, S.S.M., Gollasch, M., Yao, X. and Huang, Y. |
Abstract: | Objective: The purpose of this study was to examine the hypothesis that angiotensin II (Ang II) induced endothelial cyclooxygenase-2 (COX-2) expression, which in turn mediated the generation of proinflammatory cytokines. Methods and results: Western blot analysis on primary rat endothelial cells showed Ang II induced COX-2 expression, which was abolished by cotreatment of p38 mitogen-activated protein kinase (SB 202190) and extracellular signal-regulated kinase 1/2 (PD 98059) inhibitors. Protein kinase C{delta} (PKC{delta}) inhibitor (rottlerin) prevented extracellular signal-regulated kinase 1/2 phosphorylation and COX-2 expression. The pivotal role of PKC{delta} was further supported by a similar stimulatory effect of the PKC activator on COX-2 expression, signified by Ang II-stimulated translocation of PKC{delta} to the plasma membrane, and confirmed by PKC{delta} phosphorylation at Tyr311. Small interfering RNA targeting PKC{delta} diminished COX-2 expression, which was further abrogated by SB 202190. Human mesenteric arteries incubated with Ang II showed increased levels of endothelial COX-2 and monocyte chemoattractant protein-1; the former was inhibited by SB 202190 plus rottlerin, whereas the latter was prevented by COX-2 inhibitor. Conclusions: The present study pinpoints a novel role of PKC{delta} in Ang II-induced endothelial COX-2 upregulation and identifies a COX-2-dependent proatherosclerotic cytokine monocyte chemoattractant protein-1. The findings raise the possibility of curtailing endothelial COX-2 expression as a means of limiting or preventing vascular inflammation. |
Keywords: | Angiotensin II, Endothelium, Cyclooxygenase-2, Monocyte Chemoattractant Protein-1, Protein Kinase C-{Delta}, Animals, Rats |
Source: | Arteriosclerosis Thrombosis and Vascular Biology |
ISSN: | 1079-5642 |
Publisher: | American Heart Association |
Volume: | 31 |
Number: | 5 |
Page Range: | 1169-1176 |
Date: | May 2011 |
Official Publication: | https://doi.org/10.1161/ATVBAHA.110.216044 |
PubMed: | View item in PubMed |
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