Muscarinic Binding Sites on Bovine Pulmonary Arterial Endothelial Cells in Culture

Pharmacology ◽  
1992 ◽  
Vol 44 (6) ◽  
pp. 324-333 ◽  
Author(s):  
Robert S. Aronstam ◽  
Una S. Ryan ◽  
John D. Catravas
Keyword(s):  
Endothelial Cells ◽  
Binding Sites ◽  
Cells In Culture ◽  
Muscarinic Binding Sites ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells

Hydrogen peroxide stimulates sodium-potassium pump activity in cultured pulmonary arterial endothelial cells

1993 ◽  
Vol 265 (6) ◽  
pp. L613-L621 ◽  
Author(s):  
J. V. Meharg ◽  
J. McGowan-Jordan ◽  
A. Charles ◽  
J. T. Parmelee ◽  
M. V. Cutaia ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Binding Sites ◽  
Cell Injury ◽  
Adherent Cell ◽  
Functional Assay ◽  
Oxidant Injury ◽  
51Cr Release ◽  
Pump Activity ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells

Oxidant injury to pulmonary vascular endothelium is an important factor in the pathogenesis of acute lung injury. Oxidant injury to other cell types has been reported to alter the function of Na-K-adenosinetriphophatase (ATPase) an enzyme important in maintenance of cellular ionic homeostasis and in transport of ions across biological membranes. We investigated the effect of H2O2 (0.001-10 mM) or xanthine (X) (15.2 micrograms/ml) plus xanthine oxidase (XO) (0.0153 U/ml) on the Na-K pump activity of cultured bovine pulmonary arterial endothelial cells (PAECs). We used a functional assay, using 86RbCl as a tracer for K+ and expressing Na-K pump activity as ouabain-inhibitable K+ uptake. Our results demonstrate that H2O2 and X/XO stimulate Na-K pump activity of bovine PAECs, an effect prevented by catalase. In addition, we assessed the affinity, number, and turnover of [3H]ouabain binding sites on intact endothelial monolayers and found that H2O2 increased affinity to [3H]ouabain, decreased the number of binding sites, and increased the rate of pump turnover. Influx of 22Na increased in response to a nonlytic concentration of H2O2. Cell injury, as assessed by 51Cr release, adherent cell number, and phase-microscopic morphology, was not observed after 30-min incubations with the lowest dose (1 mM) of H2O2 effective in stimulating Na-K pump activity, or after incubation with X/XO. Na-K pump inhibition by ouabain significantly increased the 51Cr release caused by H2O2 or by X/XO, suggesting that the increase in Na-K pump activity may be a compensatory response to the cellular alterations produced by H2O2. Incubation with H2O2 decreased cell ATP content, an effect which was not prevented by coincubation with ouabain. In summary, these results show that H2O2 increases Na-K pump activity of PAECs, an effect mediated, at least in part, by increased intracellular [Na] and by an increased rate of pump turnover. It is possible that the increased pump activity may be an early marker of endothelial cell perturbation.

Arginase inhibition increases nitric oxide production in bovine pulmonary arterial endothelial cells

2004 ◽  
Vol 287 (1) ◽  
pp. L60-L68 ◽  
Author(s):  
Louis G. Chicoine ◽  
Michael L. Paffett ◽  
Tamara L. Young ◽  
Leif D. Nelin
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
No Synthase ◽  
No Production ◽  
Urea Production ◽  
Pulmonary Arterial ◽  
Factor Α ◽  
Arterial Endothelial Cells ◽  
Regular Medium ◽  
Necrosis Factor

Nitric oxide (NO) is produced by NO synthase (NOS) from l-arginine (l-Arg). Alternatively, l-Arg can be metabolized by arginase to produce l-ornithine and urea. Arginase (AR) exists in two isoforms, ARI and ARII. We hypothesized that inhibiting AR with l-valine (l-Val) would increase NO production in bovine pulmonary arterial endothelial cells (bPAEC). bPAEC were grown to confluence in either regular medium (EGM; control) or EGM with lipopolysaccharide and tumor necrosis factor-α (L/T) added. Treatment of bPAEC with L/T resulted in greater ARI protein expression and ARII mRNA expression than in control bPAEC. Addition of l-Val to the medium led to a concentration-dependent decrease in urea production and a concentration-dependent increase in NO production in both control and L/T-treated bPAEC. In a second set of experiments, control and L/T bPAEC were grown in EGM, EGM with 30 mM l-Val, EGM with 10 mM l-Arg, or EGM with both 10 mM l-Arg and 30 mM l-Val. In both control and L/T bPAEC, treatment with l-Val decreased urea production and increased NO production. Treatment with l-Arg increased both urea and NO production. The addition of the combination l-Arg and l-Val decreased urea production compared with the addition of l-Arg alone and increased NO production compared with l-Val alone. These data suggest that competition for intracellular l-Arg by AR may be involved in the regulation of NOS activity in control bPAEC and in response to L/T treatment.

Intracellular redox status affects transplasma membrane electron transport in pulmonary arterial endothelial cells

2002 ◽  
Vol 282 (1) ◽  
pp. L36-L43 ◽  
Author(s):  
Marilyn P. Merker ◽  
Robert D. Bongard ◽  
Nicholas J. Kettenhofen ◽  
Yoshiyuki Okamoto ◽  
Christopher A. Dawson
Keyword(s):  
Endothelial Cells ◽  
Electron Transport ◽  
Control Level ◽  
Redox Status ◽  
Cellular Mechanisms ◽  
Control Activity ◽  
Transplasma Membrane Electron Transport ◽  
Cell Extracts ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells

Pulmonary arterial endothelial cells possess transplasma membrane electron transport (TPMET) systems that transfer intracellular reducing equivalents to extracellular electron acceptors. As one aspect of determining cellular mechanisms involved in one such TPMET system in pulmonary arterial endothelial cells in culture, glycolysis was inhibited by treatment with iodoacetate (IOA) or by replacing the glucose in the cell medium with 2-deoxy-d-glucose (2-DG). TPMET activity was measured as the rate of reduction of the extracellular electron acceptor polymer toluidine blue O polyacrylamide. Intracellular concentrations of NADH, NAD+, NADPH, and NADP+ were determined by high-performance liquid chromatography of KOH cell extracts. IOA decreased TPMET activity to 47% of control activity concomitant with a decrease in the NADH/NAD+ ratio to 34% of the control level, without a significant change in the NADPH/NADP+ ratio. 2-DG decreased TPMET activity to 53% of control and decreased both NADH/NAD+ and NADPH/NADP+ ratios to 51% and 55%, respectively, of control levels. When lactate was included in the medium along with the inhibitors, the effects of IOA and 2-DG on both TPMET activity and the NADPH/NADP+ ratios were prevented. The results suggest that cellular redox status is a determinant of pulmonary arterial endothelial cell TPMET activity, with TPMET activity more highly correlated with the poise of the NADH/NAD+redox pair.

Matrix Stiffening Induces a Pathogenic QKI-miR-7-SRSF1 Signaling Axis in Pulmonary Arterial Endothelial Cells

2021 ◽  
Author(s):  
Chen-Shan Chen Woodcock ◽  
Neha Hafeez ◽  
Adam Handen ◽  
Ying Tang ◽  
Lloyd D Harvey ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Rna Binding ◽  
Vascular Diseases ◽  
Vascular Stiffness ◽  
Artery Stiffness ◽  
Signaling Axis ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells ◽  
Splicing Factor 1

Pulmonary arterial hypertension (PAH) refers to a set of heterogeneous vascular diseases defined by elevation of pulmonary arterial pressure (PAP) and pulmonary vascular resistance (PVR), leading to right ventricular (RV) remodeling and often death. Early increases in pulmonary artery stiffness in PAH drive pathogenic alterations of pulmonary arterial endothelial cells (PAECs), leading to vascular remodeling. Dysregulation of microRNAs can drive PAEC dysfunction. However, the role of vascular stiffness in regulating pathogenic microRNAs in PAH is incompletely understood. Here, we demonstrated that extracellular matrix (ECM) stiffening downregulated miR-7 levels in PAECs. The RNA binding protein Quaking (QKI) has been implicated in the biogenesis of miR-7. Correspondingly, we found that ECM stiffness up-regulated QKI, and QKI knockdown led to increased miR-7. Downstream of the QKI-miR-7 axis, the serine and arginine rich splicing factor 1 (SRSF1) was identified as a direct target of miR-7. Correspondingly, SRSF1 was reciprocally up-regulated in PAECs exposed to stiff ECM and was negatively correlated with miR-7. Decreased miR-7 and increased QKI and SRSF1 were observed in lungs from PAH patients and PAH rats exposed to SU5416/hypoxia. Lastly, miR-7 upregulation inhibited human PAEC migration, while forced SRSF1 expression reversed this phenotype, proving that miR-7 depended upon SRSF1 to control migration. In aggregate, these results define the QKI-miR-7-SRSF1 axis as a mechanosensitive mechanism linking pulmonary arterial vascular stiffness to pathogenic endothelial function. These findings emphasize implications relevant to PAH and suggest the potential benefit of developing therapies that target this miRNA-dependent axis in PAH.

Endothelin-1 upregulates activin receptor-like kinase-1 expression via Gi/RhoA/Sp-1/Rho kinase pathways at transcriptional and post-transcriptional levels in human pulmonary arterial endothelial cells

2020 ◽  
Author(s):  
Koichi Sugimoto ◽  
Tetsuro Yokokawa ◽  
Tomofumi Misaka ◽  
Takashi Kaneshiro ◽  
Shinya Yamada ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Quantitative Polymerase Chain Reaction ◽  
Rho Kinase ◽  
Luciferase Assay ◽  
Activin Receptor ◽  
Rhoa Activation ◽  
Pulmonary Vasoconstriction ◽  
Receptor Like Kinase ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells

Abstract BackgroundsPulmonary arterial hypertension (PAH) is a disease with poor prognosis that is characterized by pulmonary vasoconstriction and organic stenosis due to abnormal proliferation of pulmonary vascular cells. It has been demonstrated that endothelin (ET)-1 induces pulmonary vasoconstriction through activation of RhoA. Moreover, we previously demonstrated that Gi, a heterotrimeric G protein, functions upstream of RhoA activation. A gene mutation of activin receptor-like kinase (ACVRL)-1 is recognized in idiopathic or heritable PAH patients. However, little is known about the association between ET-1 and ACVRL-1. In the present study, we investigated the effect of ET-1 on ACVRL-1 expression and aimed to delineate the involvement of the Gi/RhoA/Rho kinase pathway.MethodsET-1 was added to culture medium of human pulmonary arterial endothelial cells (PAECs), and ACVRL-1 expression levels were analyzed using western blotting and quantitative polymerase chain reaction. The promoter activity of ACVRL-1 was evaluated by dual luciferase assay. Before adding ET-1 to the PAECs, pretreatment with pertussis toxin (PTX) or exoenzyme C3 transferase (C3T) was performed for the inhibition of Gi or RhoA, respectively. Rho kinase was inhibited by Y27632. Active form of RhoA (GTP-RhoA) was assessed by pull-down assay.ResultsACVRL-1 expression was increased by ET-1 in the PAECs. Pull-down assay revealed that ET-1 rapidly induced a GTP-loading of RhoA. The ET-1-induced RhoA activation was suppressed by pretreatment with PTX or C3T. Further, PTX, C3T, and Y27632 suppressed the ET-1-induced ACVRL-1 expression. The activity of ACVRL-1 promotor and the lifespan of ACVRL-1 mRNA was increased by ET-1. Sp-1, which is one of the transcriptional factors of ACVRL-1, peaked 15 min after adding ET-1 to the PAECs. PTX and C3T prevented the increase of Sp-1 induced by ET-1.ConclusionThe present study demonstrated that ET-1 increases ACVRL-1 expression at the transcriptional and post-transcriptional levels in human PAECs via the Gi/RhoA/Rho kinase pathway with involvement of Sp-1.

Activation of proMMP-2 and Src by HHV8 vGPCR in human pulmonary arterial endothelial cells

2007 ◽  
Vol 42 (3) ◽  
pp. 517-525 ◽  
Author(s):  
Bin Shan ◽  
Cindy A. Morris ◽  
Ying Zhuo ◽  
Bryan D. Shelby ◽  
Dawn R. Levy ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Arterial ◽  
Arterial Endothelial Cells

Characterization of glutamic acid uptake by bovine pulmonary arterial endothelial cells

1987 ◽  
Vol 63 (5) ◽  
pp. 1961-1965 ◽  
Author(s):  
V. Steiger ◽  
S. M. Deneke ◽  
B. L. Fanburg
Keyword(s):  
Endothelial Cells ◽  
Glutamic Acid ◽  
Cell Density ◽  
Inhibitory Effect ◽  
Transport Systems ◽  
Acid Uptake ◽  
Relative Contribution ◽  
Pulmonary Arterial ◽  
Cell Densities ◽  
Arterial Endothelial Cells

L-Glutamic acid uptake by bovine pulmonary arterial endothelial cells in culture increased linearly with time up to 30 min and did not show saturation with increased substrate concentration up to 6 X 10(-3) M. The uptake per cell decreased as cell density increased and was lowest when the cells became fully confluent. Most of the uptake was sodium dependent, although the relative contribution of sodium-independent uptake increased with an increase in cell density. Cysteic and aspartic acid strongly inhibited L-glutamic acid uptake, but at higher cell densities this effect was less pronounced than at low densities. Other amino acids, including leucine, glutamine, and serine, exerted a modest inhibitory effect at both high and low cell densities. Thus pulmonary arterial endothelial cells contain similar membrane transport systems for L-glutamic acid as those previously described for fibroblasts, hepatocytes, and nerve cells. However, quantitative properties of the transport systems differ depending on the state of cellular density in monolayers.

Cytokine treatment increases arginine metabolism and uptake in bovine pulmonary arterial endothelial cells

2001 ◽  
Vol 281 (5) ◽  
pp. L1232-L1239 ◽  
Author(s):  
Leif D. Nelin ◽  
Heather E. Nash ◽  
Louis G. Chicoine
Keyword(s):  
Endothelial Cells ◽  
Mrna Expression ◽  
Cationic Amino Acid ◽  
Cytokine Treatment ◽  
Nitrite Production ◽  
Urea Production ◽  
Pulmonary Arterial ◽  
Factor Α ◽  
Arterial Endothelial Cells ◽  
Necrosis Factor

l-Arginine (l-Arg) is metabolized to nitric oxide (NO) by NO synthase (NOS) or to urea by arginase (AR). l-Arg is transported into bovine pulmonary arterial endothelial cells (BPAECs) by cationic amino acid transporter-2 (CAT-2). We hypothesized that cytokine treatment would increase l-Arg metabolism and increase CAT-2 mRNA expression. BPAECs were incubated for 24 h in medium (control) or medium with lipopolysaccharide and tumor necrosis factor-α (L-T). L-T increased nitrite production (3.1 ± 0.4 nmol/24 h vs. 1.8 ± 0.1 nmol/24 h for control; P< 0.01) and urea production (83.5 ± 29.5 nmol/24 h vs. 17.8 ± 8.6 nmol/24 h for control; P < 0.05). L-T-treated BPAECs had greater endothelial and inducible NOS mRNA expression compared with control cells. Increasing the medium l-Arg concentration resulted in increased nitrite and urea production in both the control and the L-T-treated BPAECs. L-T treatment resulted in measurable CAT-2 mRNA. L-T increasedl-[3H]Arg uptake (5.78 ± 0.41 pmol vs. 4.45 ± 0.10 pmol for control; P < 0.05). In summary, L-T treatment increased l-Arg metabolism to both NO and urea in BPAECs and resulted in increased levels of CAT-2 mRNA. This suggests that induction of NOS and/or AR is linked to induction of CAT-2 in BPAECs and may represent a mechanism for maintainingl-Arg availability to NOS and/or AR.

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