Item Type: | Article |
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Title: | AT1 receptor agonistic antibodies from preeclamptic patients stimulate NADPH oxidase |
Creators Name: | Dechend, R., Viedt, C., Mueller, D.N., Ugele, B., Brandes, R.P., Wallukat, G., Park, J.K., Janke, J., Barta, P., Theuer, J., Fiebeler, A., Homuth, V., Dietz, R., Haller, H., Kreuzer, J. and Luft, F.C. |
Abstract: | BACKGROUND: We recently identified agonistic autoantibodies directed against the angiotensin AT1 receptor (AT1-AA) in the plasma of preeclamptic women. To elucidate their role further, we studied the effects of AT1-AA on reactive oxygen species (ROS), NADPH oxidase expression, and nuclear factor-kappaB (NF-kappaB) activation. METHODS AND RESULTS: We investigated human vascular smooth muscle cells (VSMC) and trophoblasts, as well as placentas. AT1-AA were isolated from sera of preeclamptic women. Angiotensin II (Ang II) and AT1-AA increased ROS production and the NADPH oxidase components, p22, p47, and p67 phox in Western blotting. We next tested if AT1-AA lead to NF-kappaB activation in VSMC and trophoblasts. AT1-AA activated NF-kappaB. Inhibitor-kappaBalpha (I-kappaBalpha) expression was reduced in response to AT1-AA. AT1 receptor blockade with losartan, diphenylene iodonium, tiron, and antisense against p22 phox all reduced ROS production and NF-kappaB activation. VSMC from p47phox-/- mice showed markedly reduced ROS generation and NF-kappaB activation in response to Ang II and AT1-AA. The p22, p47, and p67 phox expression in placentas from preeclamptic patients was increased, compared with normal placentas. Furthermore, NF-kappaB was activated and I-kappaBalpha reduced in placentas from preeclamptic women. CONCLUSIONS: NADPH oxidase is potentially an important source of ROS that may upregulate NF-kappaB in preeclampsia. We suggest that AT1-AA through activation of NADPH oxidase could contribute to ROS production and inflammatory responses in preeclampsia. |
Keywords: | AT1 receptors, Pregnancy, Angiotensin, Oxygen, Cells, Antibodies, Animals, Mice |
Source: | Circulation |
ISSN: | 0009-7322 |
Publisher: | American Heart Association |
Volume: | 107 |
Number: | 12 |
Page Range: | 1632-1639 |
Date: | 1 April 2003 |
Official Publication: | https://doi.org/10.1161/01.CIR.0000058200.90059.B1 |
PubMed: | View item in PubMed |
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