Inhibition of Protein Kinase C β2 Prevents Tumor Necrosis Factor-α-Induced Apoptosis and Oxidative Stress in Endothelial Cells: The Role of NADPH Oxidase Subunits
We investigate the cell signal transduction pathway protein kinase C (PKC) and the role of NADPH subunits in the process of TNF-α-induced endothelial apoptosis. Human umbilical vein endothelial cells (HUVEC) were treated with one of these: 1 mM PKC β 2 inhibitor CGP53353, 10 mM PKC δ inhibitor rottl...
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Published in | Journal of vascular research Vol. 49; no. 2; pp. 144 - 159 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Basel, Switzerland
Karger
01.04.2012
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Subjects | |
Online Access | Get full text |
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Summary: | We investigate the cell signal transduction pathway protein kinase C (PKC) and the role of NADPH subunits in the process of TNF-α-induced endothelial apoptosis. Human umbilical vein endothelial cells (HUVEC) were treated with one of these: 1 mM PKC β 2 inhibitor CGP53353, 10 mM PKC δ inhibitor rottlerin, combination CGP53353 with rottlerin, 3 ×10 –4 M NADPH oxidase inhibitor apocynin, 5 × 10 –6 M NADPH oxidase peptide inhibitor gp91ds-tat. The apoptosis process was assessed by Hoechst 33342 stain, flow cytometry and Western blot analysis, while intracellular reactive oxygen species (ROS) production was detected by 2,7’-dichlorodihydrofluorescein diacetate (DCFH-DA). The NADPH oxidase subunit gene and protein expression were assessed by quantitative real-time PCR and Western blot analysis, respectively. TNF-α significantly induced HUVEC apoptosis and ROS production, accompanying with dramatic upregulation of NADPH oxidase subunits: NOX2/gp91 phox , NOX4, p47 phox and p67 phox , whereas these enhancements were abolished by the treatment with PKC inhibitors. High TNF-α level exposure induces HUVEC apoptosis, as well as a ROS generation increase via the PKC β 2 -dependent activation of NADPH oxidase. Although the PKC δ pathway may enhance TNF-α-induced HUVEC apoptosis, it does not involve the ROS pathway. Upregulation of expression of NADPH subunits is important in this process, which leads to a new target in antioxidative therapy for vascular disease prevention. |
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ISSN: | 1018-1172 1423-0135 |
DOI: | 10.1159/000332337 |