The effects of betamethasone (BM) on endothelial nitric oxide synthase (eNOS) expression in adult baboon femoral arterial endothelial cells

Histone acetylation plays an important role in chromatin remodeling and gene expression. The molecular mechanisms involved in cell-specific expression of endothelial nitric-oxide synthase (eNOS) are not fully understood. In this study we investigated whether histone deacetylation was involved in repression of eNOS expression in non-endothelial cells. Induction of eNOS expression by histone deacetylase (HDAC) inhibitors trichostatin A (TSA) and sodium butyrate was observed in all four different types of non-endothelial cells examined. Chromatin immunoprecipitation assays showed that the induction of eNOS expression by TSA was accompanied by a remarkable increase of acetylation of histone H3 associated with the eNOS 5′-flanking region in the non-endothelial cells. Moreover, DNA methylation-mediated repression of eNOS promoter activity was partially reversed by TSA treatment, and combined treatment of TSA and 5-aza-2′-deoxycytidine (AzadC) synergistically induced eNOS expression in non-endothelial cells. The proximal Sp1 site is critical for basal activity of eNOS promoter. The induction of eNOS by inhibition of HDACs in non-endothelial cells, however, appeared not mediated by the changes in Sp1 DNA binding activity. We further showed that Sp1 bound to the endogenous eNOS promoter and associated with HDAC1 in non-endothelial HeLa cells. Combined TSA and AzadC treatment increased Sp1 binding to the endogenous eNOS promoter but decreased the association between HDAC1 and Sp1 in HeLa cells. Our data suggest that HDAC1 plays a critical role in eNOS repression, and the proximal Sp1 site may serve a key target for HDCA1-mediated eNOS repression in non-endothelial cells.

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Alkalosis stimulates endothelial nitric oxide synthase in cultured human pulmonary arterial endothelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00436.2001 ◽

2002 ◽

Vol 283 (1) ◽

pp. L113-L119 ◽

Cited By ~ 18

Author(s):

Shiro Mizuno ◽

Yoshiki Demura ◽

Shingo Ameshima ◽

Seitaro Okamura ◽

Isamu Miyamori ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Nitric Oxide Synthase ◽

Endothelial Nitric Oxide Synthase ◽

Extracellular Ph ◽

Enos Activity ◽

Pulmonary Arterial ◽

Oxide Synthase ◽

Endothelial Nitric Oxide ◽

Arterial Endothelial Cells

To investigate the effect of extracellular pH on endothelial nitric oxide synthase (eNOS) in human pulmonary arteries, we measured eNOS activity and expression as well as some ion channels in human pulmonary arterial endothelial cells (HPAEC) exposed to various pH levels (6.6–8.0). eNOS activity was found to increase with alkalization and decrease with acidification, while Ca2+ uptake into HPAEC increased with alkalization. The addition of 3′,4′-dichlorobenzamil hydrochloride, an inhibitor of the Na+/Ca2+ exchanger (NCX), prevented the increase of eNOS activity with alkalosis. Exposure to alkalosis and acidosis increased eNOS and NCX mRNA levels. These results suggest that an elevation of extracellular pH activates eNOS via the influx of extracellular Ca2+ and that NCX also regulates eNOS activity during alkalosis. Furthermore, NCX may have a tight interaction with eNOS at the level of transcription and might affect pulmonary circulation during alkalosis and acidosis.

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Endothelial nitric oxide synthase is dynamically expressed during bone marrow stem cell differentiation into endothelial cells

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01408.2006 ◽

2007 ◽

Vol 293 (3) ◽

pp. H1760-H1765 ◽

Cited By ~ 27

Author(s):

Zhenguo Liu ◽

Yuehua Jiang ◽

Hong Hao ◽

Kalpna Gupta ◽

Jian Xu ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Stem Cell ◽

Growth Factor ◽

Nitric Oxide Synthase ◽

Endothelial Nitric Oxide Synthase ◽

Stem Cell Differentiation ◽

Enos Expression ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

This study was designed to investigate the developmental expression of endothelial nitric oxide synthase (eNOS) during stem cell differentiation into endothelial cells and to examine the functional status of the newly differentiated endothelial cells. Mouse adult multipotent progenitor cells (MAPCs) were used as the source of stem cells and were induced to differentiate into endothelial cells with vascular endothelial growth factor (VEGF) in serum-free medium. Expression of eNOS in the cells during differentiation was evaluated with real-time PCR, nitric oxide synthase (NOS) activity, and Western blot analysis. It was found that eNOS, but no other NOS, was present in undifferentiated MAPCs. eNOS expression disappeared in the cells immediately after induction of differentiation. However, eNOS expression reoccurred at day 7 during differentiation. Increasing eNOS mRNA, protein content, and activity were observed in the cells at days 14 and 21 during differentiation. The differentiated endothelial cells formed dense capillary networks on growth factor-reduced Matrigel. VEGF-stimulated phosphorylation of extracellular signal-regulated kinase (ERK)-1 and ERK-2 occurred in these cells, which was inhibited by NOS inhibitor NG-nitro-l-arginine methyl ester. In conclusion, these data demonstrate that eNOS is present in MAPCs and is dynamically expressed during the differentiation of MAPCs into endothelial cells in vitro.

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L-citrulline increases arginase II protein levels and arginase activity in hypoxic piglet pulmonary artery endothelial cells

Pulmonary Circulation ◽

10.1177/20458940211006289 ◽

2021 ◽

Vol 11 (2) ◽

pp. 204589402110062

Author(s):

Matthew S. Douglass ◽

Yongmei Zhang ◽

Mark R. Kaplowitz ◽

Candice D. Fike

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Nitric Oxide Synthase ◽

Endothelial Nitric Oxide Synthase ◽

Nitric Oxide Production ◽

Oxide Production ◽

Pulmonary Arterial ◽

Oxide Synthase ◽

Endothelial Nitric Oxide ◽

Arterial Endothelial Cells

The L-arginine precursor, L-citrulline, re-couples endothelial nitric oxide synthase, increases nitric oxide production, and ameliorates chronic hypoxia-induced pulmonary hypertension in newborn pigs. L-arginine can induce arginase, which, in turn, may diminish nitric oxide production. Our major purpose was to determine if L-citrulline increases arginase activity in hypoxic piglet pulmonary arterial endothelial cells, and if so, concomitantly impacts the ability to increase endothelial nitric oxide synthase re-coupling and nitric oxide production. Piglet pulmonary arterial endothelial cells were cultured in hypoxic conditions with L-citrulline (0–3 mM) and/or the arginase inhibitor S-(2-boronoethyl)-L-cysteine. We measured arginase activity and nitric oxide production. We assessed endothelial nitric oxide synthase coupling by measuring endothelial nitric oxide synthase dimers and monomers. L-citrulline concentrations ≥0.5 mM increased arginase activity in hypoxic pulmonary arterial endothelial cells. L-citrulline concentrations ≥0.1 mM increased nitric oxide production and concentrations ≥0.5 mM elevated endothelial nitric oxide synthase dimer-to-monomer ratios. Co-treatment with L-citrulline and S-(2-boronoethyl)-L-cysteine elevated endothelial nitric oxide synthase dimer-to-monomer ratios more than sole treatment. Despite inducing arginase, L-citrulline increased nitric oxide production and endothelial nitric oxide synthase coupling in hypoxic piglet pulmonary arterial endothelial cells. However, these dose-dependent findings raise the possibility that there could be L-citrulline concentrations that elevate arginase to levels that negate improvements in endothelial nitric oxide synthase dysfunction. Moreover, our findings suggest that combining an arginase inhibitor with L-citrulline merits evaluation as a treatment for chronic hypoxia-induced pulmonary hypertension.

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Role of Intronic MicroRNA in The Regulation of Endothelial Nitric Oxide Synthase Expression and The Proliferation of Endothelial Cells*

PROGRESS IN BIOCHEMISTRY AND BIOPHYSICS ◽

10.3724/sp.j.1206.2009.00755 ◽

2010 ◽

Vol 37 (7) ◽

pp. 747-753 ◽

Cited By ~ 4

Author(s):

Li-Mei YAN ◽

Jian-Yong WU ◽

Xiao-Hua YU ◽

Jing-Ou XU ◽

He-Sheng OU

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Nitric Oxide Synthase ◽

Endothelial Nitric Oxide Synthase ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

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Ficus deltoidea enhances expression of endothelial nitric oxide synthase and reduces endothelin-1 on stimulated human coronary artery endothelial cells

Atherosclerosis ◽

10.1016/j.atherosclerosis.2016.07.762 ◽

2016 ◽

Vol 252 ◽

pp. e157-e158 ◽

Cited By ~ 1

Author(s):

R. Ahmad ◽

T. Rahman ◽

N.A. Mohd Kasim ◽

G.A. Froemming ◽

S. Muid ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Coronary Artery ◽

Nitric Oxide Synthase ◽

Endothelial Nitric Oxide Synthase ◽

Human Coronary Artery ◽

Ficus Deltoidea ◽

Endothelin 1 ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

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Rho GTPase/Rho Kinase Negatively Regulates Endothelial Nitric Oxide Synthase Phosphorylation through the Inhibition of Protein Kinase B/Akt in Human Endothelial Cells

Molecular and Cellular Biology ◽

10.1128/mcb.22.24.8467-8477.2002 ◽

2002 ◽

Vol 22 (24) ◽

pp. 8467-8477 ◽

Cited By ~ 298

Author(s):

Xiu-Fen Ming ◽

Hema Viswambharan ◽

Christine Barandier ◽

Jean Ruffieux ◽

Kozo Kaibuchi ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Cells ◽

Endothelial Nitric Oxide Synthase ◽

Rho Gtpase ◽

Protein Kinase B ◽

Rho Kinase ◽

Enos Expression ◽

Enos Phosphorylation ◽

Oxide Synthase ◽

Endothelial Nitric Oxide

ABSTRACT Endothelial nitric oxide synthase (eNOS) is an important regulator of cardiovascular homeostasis by production of nitric oxide (NO) from vascular endothelial cells. It can be activated by protein kinase B (PKB)/Akt via phosphorylation at Ser-1177. We are interested in the role of Rho GTPase/Rho kinase (ROCK) pathway in regulation of eNOS expression and activation. Using adenovirus-mediated gene transfer in human umbilical vein endothelial cells (HUVECs), we show here that both active RhoA and ROCK not only downregulate eNOS gene expression as reported previously but also inhibit eNOS phosphorylation at Ser-1177 and cellular NO production with concomitant suppression of PKB activation. Moreover, coexpression of a constitutive active form of PKB restores the phosphorylation but not gene expression of eNOS in the presence of active RhoA. Furthermore, we show that thrombin inhibits eNOS phosphorylation, as well as expression via Rho/ROCK pathway. Expression of the active PKB reverses eNOS phosphorylation but has no effect on downregulation of eNOS expression induced by thrombin. Taken together, these data demonstrate that Rho/ROCK pathway negatively regulates eNOS phosphorylation through inhibition of PKB, whereas it downregulates eNOS expression independent of PKB.

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