Regulation of Glutathione by Oxidative Stress in Bovine Pulmonary Artery Endothelial Cells

[Ca2+]i (cytosolic [Ca2+]) and OS (oxidative stress) were measured simultaneously in calf pulmonary artery endothelial cells using fura-2 and carboxy-2´,7´-dichlorodihydrofluorescein. ATP stimulated a [Ca2+]i increase that was followed a few seconds later by an increase in OS. Pre-exposure to 5 μM H2O2 potentiated these responses to ATP. Elevating or removing extracellular Ca2+ increased or reduced the [Ca2+]i response to ATP and caused parallel changes in the OS response, suggesting that this response was a consequence of the [Ca2+]i response. Inhibition of mitochondria with rotenone or antimycin A affected the responses but not in a manner that allowed a simple interpretation of the role of mitochondria. These data show an initimate connection between [Ca2+]i and OS that can be modulated by low levels of exogenously applied OS, allowing the possibility of positive feedback.

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Pollutant particles enhanced H2O2 production from NAD(P)H oxidase and mitochondria in human pulmonary artery endothelial cells

AJP Cell Physiology ◽

10.1152/ajpcell.00365.2005 ◽

2006 ◽

Vol 291 (2) ◽

pp. C357-C365 ◽

Cited By ~ 50

Author(s):

Zhuowei Li ◽

Xhevahire Hyseni ◽

Jacqueline D. Carter ◽

Joleen M. Soukup ◽

Lisa A. Dailey ◽

...

Keyword(s):

Oxidative Stress ◽

Endothelial Cells ◽

Pulmonary Artery ◽

Health Effects ◽

Vascular Endothelial Cells ◽

Water Soluble ◽

H2o2 Production ◽

Vascular Endothelial ◽

Human Pulmonary Artery ◽

P38 Mapks

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 Nω-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.

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Bleomycin upregulates expression of γ-glutamylcysteine synthetase in pulmonary artery endothelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00338.2001 ◽

2002 ◽

Vol 282 (6) ◽

pp. L1349-L1357 ◽

Cited By ~ 15

Author(s):

Regina M. Day ◽

Yuichiro j. Suzuki ◽

Julie M. Lum ◽

Alexander C. White ◽

Barry L. Fanburg

Keyword(s):

Oxidative Stress ◽

Endothelial Cells ◽

Stress Response ◽

Pulmonary Artery ◽

Antioxidant Response ◽

Nuclear Factor Κb ◽

Oxidative Stress Response ◽

Cellular Damage ◽

Mobility Shift ◽

Glutamylcysteine Synthetase

The chemotherapeutic agent bleomycin induces pulmonary fibrosis through the generation of reactive oxygen species (ROS), which are thought to contribute to cellular damage and pulmonary injury. We hypothesized that bleomycin activates oxidative stress response pathways and regulates cellular glutathione (GSH). Bovine pulmonary artery endothelial cells exposed to bleomycin exhibit growth arrest and increased cellular GSH content. γ-Glutamylcysteine synthetase (γ-GCS) controls the key regulatory step in GSH synthesis, and Northern blots indicate that the γ-GCS catalytic subunit [γ-GCS heavy chain (γ-GCSh)] is upregulated by bleomycin within 3 h. The promoter for human γ-GCShcontains consensus sites for nuclear factor-κB (NF-κB) and the antioxidant response element (ARE), both of which are activated in response to oxidative stress. Electrophoretic mobility shift assays show that bleomycin activates the transcription factor NF-κB as well as the ARE-binding factors Nrf-1 and -2. Nrf-1 and -2 activation by bleomycin is inhibited by the ROS quenching agent N-acetylcysteine (NAC), but not by U-0126, a MEK1/2 inhibitor that blocks bleomycin-induced MAPK activation. In contrast, NF-κB activation by bleomycin is inhibited by U-0126, but not by NAC. NAC and U-0126 both inhibit bleomycin-induced upregulation of γ-GCS expression. These data suggest that bleomycin can activate oxidative stress response pathways and upregulate cellular GSH.

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Interaction of endothelial nitric oxide synthase with mitochondria regulates oxidative stress and function in fetal pulmonary artery endothelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00386.2014 ◽

2015 ◽

Vol 309 (9) ◽

pp. L1009-L1017 ◽

Cited By ~ 8

Author(s):

Girija G. Konduri ◽

Adeleye J. Afolayan ◽

Annie Eis ◽

Kirkwood A. Pritchard ◽

Ru-Jeng Teng

Keyword(s):

Oxidative Stress ◽

Nitric Oxide ◽

Endothelial Cells ◽

Nitric Oxide Synthase ◽

Pulmonary Artery ◽

Endothelial Nitric Oxide Synthase ◽

Pulmonary Arteries ◽

Mitochondrial Outer Membrane ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

An increase in oxygen tension at birth is one of the key signals that initiate pulmonary vasodilation in the fetal lung. We investigated the hypothesis that targeting endothelial nitric oxide synthase (eNOS) to the mitochondrial outer membrane regulates reactive oxygen species (ROS) formation in the fetal pulmonary artery endothelial cells (PAEC) during this transition. We isolated PAEC and pulmonary arteries from 137-day gestation fetal lambs (term = 144 days). We exposed PAEC to a simulated transition from fetal to (3% O2) to normoxic (21%) or hyperoxic (95% O2) postnatal Po2 or to the nitric oxide synthase (NOS) agonist ATP. We assessed the effect of O2 and ATP on eNOS interactions with the mitochondrial outer membrane protein porin and with the chaperone hsp90. We also investigated the effect of decoy peptides that blocked eNOS interactions with porin or hsp90 on PAEC angiogenesis and vasodilator function of pulmonary arteries. Transition of fetal PAEC from 3 to 21% O2 but not to 95% O2 or exposure to ATP increased eNOS association with hsp90 and porin. Decoy peptides that blocked eNOS interactions decreased NO release, increased O2 consumption and mitochondrial ROS levels, and impaired PAEC angiogenesis. Decoy peptides also inhibited the relaxation responses of pulmonary artery rings and dilation of resistance size pulmonary arteries to ATP. The mitochondrial-antioxidant mito-ubiquinone restored the response to ATP in decoy peptide-treated pulmonary arteries. These data indicate that targeting eNOS to mitochondria decreases endothelial oxidative stress and facilitates vasodilation in fetal pulmonary circulation at birth.

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Optical studies of oxidative stress in pulmonary artery endothelial cells

10.1117/12.2076658 ◽

2015 ◽

Author(s):

Zahra Ghanian ◽

Reyhaneh Sepehr ◽

Annie Eis ◽

Ganesh Kondouri ◽

Mahsa Ranji

Keyword(s):

Oxidative Stress ◽

Endothelial Cells ◽

Pulmonary Artery ◽

Optical Studies

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