|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
VASCULAR BIOLOGY
1Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina, Chapel Hill; and 2National Health and Environmental Effects Research Laboratory, Office of Research and Development, Environmental Protection Agency, Research Triangle Park, North Carolina
Submitted 20 July 2005 ; accepted in final form 24 March 2006
Particulate matter (PM) induces oxidative stress and cardiovascular adverse health effects, but the mechanistic link between the two is unclear. We hypothesized that PM enhanced oxidative stress in vascular endothelial cells and investigated the enzymatic sources of reactive oxygen species and their effects on mitogen-activated protein kinase (MAPK) activation and vasoconstriction. We measured the production of extracellular H2O2, activation of extracellular signal-regulated kinases1/2 (ERK1/2) and p38 MAPKs in human pulmonary artery endothelial cells (HPAEC) treated with urban particles (UP; SRM1648), and assessed the effects of H2O2 on vasoconstriction in pulmonary artery ring and isolated perfused lung. Within minutes after UP treatment, HPAEC increased H2O2 production that could be inhibited by diphenyleneiodonium (DPI), apocynin (APO), and sodium azide (NaN3). The water-soluble fraction of UP as well as its two transition metal components, Cu and V, also stimulated H2O2 production. NaN3 inhibited H2O2 production stimulated by Cu and V, whereas DPI and APO inhibited only Cu-stimulated H2O2 production. Inhibitors of other H2O2-producing enzymes, including N
-methyl-L-argnine, indomethacin, allopurinol, cimetidine, rotenone, and antimycin, had no effects. DPI but not NaN3 attenuated UP-induced pulmonary vasoconstriction and phosphorylation of ERK1/2 and p38 MAPKs. Knockdown of p47phox gene expression by small interfering RNA attenuated UP-induced H2O2 production and phosphorylation of ERK1/2 and p38 MAPKs. Intravascular administration of H2O2 generated by glucose oxidase increased pulmonary artery pressure. We conclude that UP induce oxidative stress in vascular endothelial cells by activating NAD(P)H oxidase and the mitochondria. The endothelial oxidative stress may be an important mechanism for PM-induced acute cardiovascular health effects.
mitogen-activated protein kinase; extracellular signal-regulated kinase; p38; vasoconstriction
This article has been cited by other articles:
![]() |
Q. Sun, P. Yue, Z. Ying, A. J. Cardounel, R. D. Brook, R. Devlin, J.-S. Hwang, J. L. Zweier, L. C. Chen, and S. Rajagopalan Air Pollution Exposure Potentiates Hypertension Through Reactive Oxygen Species-Mediated Activation of Rho/ROCK Arterioscler. Thromb. Vasc. Biol., October 1, 2008; 28(10): 1760 - 1766. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Hwang, R. A. Kloner, M. T. Kleinman, and B. Z. Simkhovich Direct and Acute Cardiotoxic Effects of Ultrafine Air Pollutants in Spontaneously Hypertensive Rats and Wistar--Kyoto Rats Journal of Cardiovascular Pharmacology and Therapeutics, September 1, 2008; 13(3): 189 - 198. [Abstract] [PDF] |
||||
![]() |
M. Medhora, Y. Chen, S. Gruenloh, D. Harland, S. Bodiga, J. Zielonka, D. Gebremedhin, Y. Gao, J. R. Falck, S. Anjaiah, et al. 20-HETE increases superoxide production and activates NAPDH oxidase in pulmonary artery endothelial cells Am J Physiol Lung Cell Mol Physiol, May 1, 2008; 294(5): L902 - L911. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |