51
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Heiss EH, Dirsch VM. Regulation of eNOS enzyme activity by posttranslational modification. Curr Pharm Des 2015; 20:3503-13. [PMID: 24180389 DOI: 10.2174/13816128113196660745] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/21/2013] [Indexed: 02/07/2023]
Abstract
The regulation of endothelial NO synthase (eNOS) employs multiple different cellular control mechanisms impinging on level and activity of the enzyme. This review aims at summarizing the current knowledge on the posttranslational modifications of eNOS, including acylation, nitrosylation, phosphorylation, acetylation, glycosylation and glutathionylation. Sites, mediators and impact on enzyme localization and activity of the single modifications will be discussed. Moreover, interdependence, cooperativity and competition between the different posttranslational modifications will be elaborated with special emphasis on the susceptibility of eNOS to metabolic cues.
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Affiliation(s)
| | - Verena M Dirsch
- University of Vienna, Department of Pharmacognosy, Althanstrasse14, 1090 Vienna, Austria.
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52
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Molecular modeling and simulation of the human eNOS reductase domain, an enzyme involved in the release of vascular nitric oxide. J Mol Model 2014; 20:2470. [DOI: 10.1007/s00894-014-2470-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 09/14/2014] [Indexed: 01/19/2023]
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53
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Ramadoss J, Pastore MB, Magness RR. Endothelial caveolar subcellular domain regulation of endothelial nitric oxide synthase. Clin Exp Pharmacol Physiol 2014; 40:753-64. [PMID: 23745825 DOI: 10.1111/1440-1681.12136] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 05/29/2013] [Accepted: 05/31/2013] [Indexed: 12/12/2022]
Abstract
Complex regulatory processes alter the activity of endothelial nitric oxide synthase (eNOS) leading to nitric oxide (NO) production by endothelial cells under various physiological states. These complex processes require specific subcellular eNOS partitioning between plasma membrane caveolar domains and non-caveolar compartments. Translocation of eNOS from the plasma membrane to intracellular compartments is important for eNOS activation and subsequent NO biosynthesis. We present data reviewing and interpreting information regarding: (i) the coupling of endothelial plasma membrane receptor systems in the caveolar structure relative to eNOS trafficking; (ii) how eNOS trafficking relates to specific protein-protein interactions for inactivation and activation of eNOS; and (iii) how these complex mechanisms confer specific subcellular location relative to eNOS multisite phosphorylation and signalling. Dysfunction in the regulation of eNOS activation may contribute to several disease states, in particular gestational endothelial abnormalities (pre-eclampsia, gestational diabetes etc.), that have life-long deleterious health consequences that predispose the offspring to develop hypertensive disease, Type 2 diabetes and adiposity.
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Affiliation(s)
- Jayanth Ramadoss
- Department of Obstetrics and Gynaecology, University of Texas Medical Branch, Galveston, TX, USA
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54
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Hydrogen sulfide increases nitric oxide production and subsequent S-nitrosylation in endothelial cells. ScientificWorldJournal 2014; 2014:480387. [PMID: 24971375 PMCID: PMC4055124 DOI: 10.1155/2014/480387] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 05/05/2014] [Indexed: 12/15/2022] Open
Abstract
Hydrogen sulfide (H2S) and nitric oxide (NO), two endogenous gaseous molecules in endothelial cells, got increased attention with respect to their protective roles in the cardiovascular system. However, the details of the signaling pathways between H2S and NO in endothelia cells remain unclear. In this study, a treatment with NaHS profoundly increased the expression and the activity of endothelial nitric oxide synthase. Elevated gaseous NO levels were observed by a novel and specific fluorescent probe, 5-amino-2-(6-hydroxy-3-oxo-3H-xanthen-9-yl)benzoic acid methyl ester (FA-OMe), and quantified by flow cytometry. Further study indicated an increase of upstream regulator for eNOS activation, AMP-activated protein kinase (AMPK), and protein kinase B (Akt). By using a biotin switch, the level of NO-mediated protein S-nitrosylation was also enhanced. However, with the addition of the NO donor, NOC-18, the expressions of cystathionine-γ-lyase, cystathionine-β-synthase, and 3-mercaptopyruvate sulfurtransferase were not changed. The level of H2S was also monitored by a new designed fluorescent probe, 4-nitro-7-thiocyanatobenz-2-oxa-1,3-diazole (NBD-SCN) with high specificity. Therefore, NO did not reciprocally increase the expression of H2S-generating enzymes and the H2S level. The present study provides an integrated insight of cellular responses to H2S and NO from protein expression to gaseous molecule generation, which indicates the upstream role of H2S in modulating NO production and protein S-nitrosylation.
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55
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Andrade FA, Restini CBA, Grando MD, Ramalho LNZ, Bendhack LM. Vascular relaxation induced by C-type natriuretic peptide involves the ca2+/NO-synthase/NO pathway. PLoS One 2014; 9:e95446. [PMID: 24787693 PMCID: PMC4006788 DOI: 10.1371/journal.pone.0095446] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 03/27/2014] [Indexed: 12/21/2022] Open
Abstract
AIMS C-type natriuretic peptide (CNP) and nitric oxide (NO) are endothelium-derived factors that play important roles in the regulation of vascular tone and arterial blood pressure. We hypothesized that NO produced by the endothelial NO-synthase (NOS-3) contributes to the relaxation induced by CNP in isolated rat aorta via activation of endothelial NPR-C receptor. Therefore, the aim of this study was to investigate the putative contribution of NO through NPR-C activation in the CNP induced relaxation in isolated conductance artery. MAIN METHODS Concentration-effect curves for CNP were constructed in aortic rings isolated from rats. Confocal microscopy was used to analyze the cytosolic calcium mobilization induced by CNP. The phosphorylation of the residue Ser1177 of NOS was analyzed by Western blot and the expression and localization of NPR-C receptors was analyzed by immunohistochemistry. KEY FINDINGS CNP was less potent in inducing relaxation in denuded endothelium aortic rings than in intact ones. L-NAME attenuated the potency of CNP and similar results were obtained in the presence of hydroxocobalamin, an intracellular NO0 scavenger. CNP did not change the phosphorylation of Ser1177, the activation site of NOS-3, when compared with control. The addition of CNP produced an increase in [Ca2+]c in endothelial cells and a decrease in [Ca2+]c in vascular smooth muscle cells. The NPR-C-receptors are expressed in endothelial and adventitial rat aortas. SIGNIFICANCE These results suggest that CNP-induced relaxation in intact aorta isolated from rats involves NO production due to [Ca2+]c increase in endothelial cells possibly through NPR-C activation expressed in these cells. The present study provides a breakthrough in the understanding of the close relationship between the vascular actions of nitric oxide and CNP.
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Affiliation(s)
- Fernanda A. Andrade
- Department of Pharmacology, School of Medicine of Ribeirão Preto - University of São Paulo, São Paulo, Brasil
| | | | - Marcella D. Grando
- Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto - University of São Paulo, São Paulo, Brasil
| | - Leandra N. Z. Ramalho
- Department of Cellular and Molecular Pathology, School of Medicine of Ribeirão Preto - University of São Paulo, São Paulo, Brasil
| | - Lusiane M. Bendhack
- Department of Physics and Chemistry, Faculty of Pharmaceutical Sciences of Ribeirão Preto - University of São Paulo, São Paulo, Brasil
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56
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Liu S, Premont RT, Rockey DC. Endothelial nitric-oxide synthase (eNOS) is activated through G-protein-coupled receptor kinase-interacting protein 1 (GIT1) tyrosine phosphorylation and Src protein. J Biol Chem 2014; 289:18163-74. [PMID: 24764294 DOI: 10.1074/jbc.m113.521203] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Nitric oxide (NO) is a critical regulator of vascular tone and plays an especially prominent role in liver by controlling portal blood flow and pressure within liver sinusoids. Synthesis of NO in sinusoidal endothelial cells by endothelial nitric-oxide synthase (eNOS) is regulated in response to activation of endothelial cells by vasoactive signals such as endothelins. The endothelin B (ETB) receptor is a G-protein-coupled receptor, but the mechanisms by which it regulates eNOS activity in sinusoidal endothelial cells are not well understood. In this study, we built on two previous strands of work, the first showing that G-protein βγ subunits mediated activation of phosphatidylinositol 3-kinase and Akt to regulate eNOS and the second showing that eNOS directly bound to the G-protein-coupled receptor kinase-interacting protein 1 (GIT1) scaffold protein, and this association stimulated NO production. Here we investigated the mechanisms by which the GIT1-eNOS complex is formed and regulated. GIT1 was phosphorylated on tyrosine by Src, and Y293F and Y554F mutations reduced GIT1 phosphorylation as well as the ability of GIT1 to bind to and activate eNOS. Akt phosphorylation activated eNOS (at Ser(1177)), and Akt also regulated the ability of Src to phosphorylate GIT1 as well as GIT1-eNOS association. These pathways were activated by endothelin-1 through the ETB receptor; inhibiting receptor-activated G-protein βγ subunits blocked activation of Akt, GIT1 tyrosine phosphorylation, and ET-1-stimulated GIT1-eNOS association but did not affect Src activation. These data suggest a model in which Src and Akt cooperate to regulate association of eNOS with the GIT1 scaffold to facilitate NO production.
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Affiliation(s)
- Songling Liu
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
| | - Richard T Premont
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710
| | - Don C Rockey
- From the Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425 and
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57
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Tobin GAM, Zhang J, Goodwin D, Stewart S, Xu L, Knapton A, González C, Bancos S, Zhang L, Lawton MP, Enerson BE, Weaver JL. The role of eNOS phosphorylation in causing drug-induced vascular injury. Toxicol Pathol 2014; 42:709-24. [PMID: 24705881 DOI: 10.1177/0192623314522885] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Previously we found that regulation of eNOS is an important part of the pathogenic process of Drug-induced vascular injury (DIVI) for PDE4i. The aims of the current study were to examine the phosphorylation of eNOS in mesentery versus aorta at known regulatory sites across DIVI-inducing drug classes and to compare changes across species. We found that phosphorylation at S615 in rats was elevated 35-fold 2 hr after the last dose of CI-1044 in mesentery versus 3-fold in aorta. Immunoprecipitation studies revealed that many of the upstream regulators of eNOS activation were associated with eNOS in 1 or more signalosome complexes. Next rats were treated with drugs from 4 other classes known to cause DIVI. Each drug was given alone and in combination with SIN-1 (NO donor) or L-NAME (eNOS inhibitor), and the level of eNOS phosphorylation in mesentery and aorta tissue was correlated with the extent of vascular injury and measured serum nitrite. Drugs or combinations produced altered serum nitrite levels as well as vascular injury score in the mesentery. The results suggested that phosphorylation of S615 may be associated with DIVI activity. Studies with the species-specific A2A adenosine agonist CI-947 in rats versus primates showed a similar pattern.
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Affiliation(s)
- Grainne A McMahon Tobin
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Jun Zhang
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - David Goodwin
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Sharron Stewart
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Lin Xu
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Alan Knapton
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Carlos González
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Simona Bancos
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
| | - Leshuai Zhang
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA Department of Anatomy & Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA
| | - Michael P Lawton
- Drug Safety Research and Development, Pfizer Inc, Groton, Connecticut, USA
| | - Bradley E Enerson
- Drug Safety Research and Development, Pfizer Inc, Groton, Connecticut, USA
| | - James L Weaver
- Division of Applied Regulatory Science, CDER, U.S. Food and Drug Administration, Silver Spring, Maryland, USA
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58
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Tomada I, Negrão R, Almeida H, Neves D. Long-term high-fat consumption leads to downregulation of Akt phosphorylation of eNOS at Ser1177 and upregulation of Sirtuin-1 expression in rat cavernous tissue. AGE (DORDRECHT, NETHERLANDS) 2014; 36:597-611. [PMID: 24105250 PMCID: PMC4039277 DOI: 10.1007/s11357-013-9591-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Accepted: 09/26/2013] [Indexed: 06/02/2023]
Abstract
Long-term consumption of high-fat diets negatively interferes with metabolic status and promotes endothelial dysfunction and inflammation. In the cavernous tissue, these outcomes become conspicuous in the elderly and strongly affect penile erection, a vascular process highly dependent on local nitric oxide bioavailability. Although epidemiological data links erectile dysfunction to nutritional patterns, the underlying molecular mechanisms remain unclear. Therefore, we investigated the effects of long-term high-fat diet on endothelial nitric oxide synthase (eNOS)-Sirtuin-1 axis and Akt/eNOS phosphorylation in the cavernous tissue of Sprague-Dawley rats, and compared with energy-restricted animals. We demonstrated that high-fat diet intake led to a noteworthy decrease in eNOS phosphorylation at Ser1177 residue through the Akt pathway, which seems to be compensated by upregulation of phosphorylation at Ser615, but without an increment in nitric oxide production. These results are accompanied by an increase of systemic inflammatory markers and upregulation of the inducible NOS and of the deacetylase Sirtuin-1 in the cavernous tissue to levels apparently detrimental to cells and to metabolic homeostasis. Conversely, in long-term energy-restricted animals, the rate of phosphorylation of eNOS at Ser1177 diminished, but the activation of the enzyme increased through phosphorylation of eNOS at Ser615, resulting in an enhancement in nitric oxide bioavailability. Taken together, our results demonstrate that long-term nutritional conditions override the influence of age on the eNOS expression and activation in rat cavernous tissue.
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Affiliation(s)
- I Tomada
- Department of Experimental Biology of Faculty of Medicine, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal,
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59
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Qian J, Fulton D. Post-translational regulation of endothelial nitric oxide synthase in vascular endothelium. Front Physiol 2013; 4:347. [PMID: 24379783 PMCID: PMC3861784 DOI: 10.3389/fphys.2013.00347] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/11/2013] [Indexed: 01/22/2023] Open
Abstract
Nitric oxide (NO) is a short-lived gaseous signaling molecule. In blood vessels, it is synthesized in a dynamic fashion by endothelial nitric oxide synthase (eNOS) and influences vascular function via two distinct mechanisms, the activation of soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP)-dependent signaling and the S-nitrosylation of proteins with reactive thiols (S-nitrosylation). The regulation of eNOS activity and NO bioavailability is critical to maintain blood vessel function. The activity of eNOS and ability to generate NO is regulated at the transcriptional, posttranscriptional, and posttranslational levels. Post-translational modifications acutely impact eNOS activity and dysregulation of these mechanisms compromise eNOS activity and foster the development of cardiovascular diseases (CVDs). This review will intergrate past and current literature on the post-translational modifications of eNOS in both health and disease.
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Affiliation(s)
- Jin Qian
- Pulmonary and Critical Care, School of Medicine, Stanford University/VA Palo Alto Health Care System Palo Alto, CA, USA
| | - David Fulton
- Vascular Biology Center, Georgia Regents University Augusta, GA, USA
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60
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Gao P, Yoo SH, Lee KJ, Rosensweig C, Takahashi JS, Chen BP, Green CB. Phosphorylation of the cryptochrome 1 C-terminal tail regulates circadian period length. J Biol Chem 2013; 288:35277-86. [PMID: 24158435 PMCID: PMC3853276 DOI: 10.1074/jbc.m113.509604] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The Cryptochrome (CRY) proteins are critical components of the mammalian circadian clock and act to rhythmically repress the activity of the transcriptional activators CLOCK and BMAL1 at the heart of the clock mechanism. The CRY proteins are part of a large repressive complex, the components of which are not completely known. Using mass spectroscopy, we identified the catalytic subunit of DNA-dependent protein kinase as a CRY-interacting protein and found that loss or inhibition of this kinase results in circadian rhythms with abnormally long periods. We then identified serine 588 in the C-terminal tail of mouse CRY1 as a potential DNA-PK phosphorylation site but surprisingly found that the phosphomimetic mutation S588D also results in long period rhythms, similar to the loss of DNA-PK. Consistent with this, we found that phosphorylation of this site is increased in cells lacking DNA-PK, suggesting that DNA-PK negatively regulates the phosphorylation of this site most likely through indirect means. Furthermore, we found that phosphorylation of this site increases the stability of the CRY1 protein and prevents FBXL3-mediated degradation. The phosphorylation of this site is robustly rhythmic in mouse liver nuclei, peaking in the middle of the circadian day at a time when CRY1 levels are declining. Therefore, these data suggest a new role for the C-terminal tail of CRY1 in which phosphorylation rhythmically regulates CRY1 stability and contributes to the proper circadian period length.
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Affiliation(s)
- Peng Gao
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Seung-Hee Yoo
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- the Howard Hughes Medical Institute, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, and
| | - Kyung-Jong Lee
- the Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Clark Rosensweig
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Joseph S. Takahashi
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- the Howard Hughes Medical Institute, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390, and
| | - Benjamin P. Chen
- the Department of Radiation Oncology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
| | - Carla B. Green
- From the Department of Neuroscience, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390
- To whom correspondence should be addressed: Dept. of Neuroscience, ND4.124A, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9111. Tel.: 214-648-7433; Fax: 214-648-1801; E-mail:
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61
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Subramanian K, Naik VD, Sathishkumar K, Sawant OB, Washburn SE, Wu G, Yallampalli C, Saade GR, Hankins GD, Ramadoss J. Interactive effects of in vitro binge-like alcohol and ATP on umbilical endothelial nitric oxide synthase post-translational modifications and redox modulation. Reprod Toxicol 2013; 43:94-101. [PMID: 24300283 DOI: 10.1016/j.reprotox.2013.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 10/29/2013] [Accepted: 11/22/2013] [Indexed: 01/01/2023]
Abstract
Alcohol dysregulates the regulation of reproductive vascular adaptations. We herein investigated chronic in vitro binge-like alcohol effects on umbilical endothelial nitric oxide synthase (eNOS) multi-site phosphorylation and related redox switches under basal (unstimulated) and stimulated (with ATP) states. Alcohol decreased endothelial excitatory (Pser1177)eNOS (P<0.001), whereas excitatory (Pser635)eNOS exhibited a main effect of alcohol (↓P=0.016) and ATP (↑P<0.001). Alcohol decreased (Pthr495)eNOS (P=0.004) levels, whereas inhibitory (Pser116)eNOS exhibited an alcohol main effect in both basal and stimulated states (↑P=0.005). Total eNOS was reduced by alcohol (P=0.038). In presence of ATP, alcohol inhibited ERK activity (P=0.002), whereas AKT exhibited no alcohol effect. Alcohol main effect on S-nitroso-glutathione reductase (↓P=0.031) and glutathione-S-transferase (↓P=0.027) were noted. Increased protein glutathiolation was noted, whereas no alcohol effect on GSH, GSSG, NOX2 or SOD expression was noted. Thus, alcohol effects on multi-site post-translational modifications and redox switches related to vasodilatory eNOS underscore the necessity for investigating alcohol-induced gestational vascular dysfunction.
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Affiliation(s)
- Kaviarasan Subramanian
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Vishal D Naik
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Kunju Sathishkumar
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Onkar B Sawant
- Department of Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Shannon E Washburn
- Department of Physiology and Pharmacology, Texas A&M University, College Station, TX, USA
| | - Guoyao Wu
- Department of Animal Sciences, Texas A&M University, College Station, TX, USA
| | - Chandra Yallampalli
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - George R Saade
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Gary D Hankins
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jayanth Ramadoss
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA.
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62
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Conti V, Russomanno G, Corbi G, Izzo V, Vecchione C, Filippelli A. Adrenoreceptors and nitric oxide in the cardiovascular system. Front Physiol 2013; 4:321. [PMID: 24223559 PMCID: PMC3818479 DOI: 10.3389/fphys.2013.00321] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/16/2013] [Indexed: 02/03/2023] Open
Abstract
Nitric Oxide (NO) is a small molecule that continues to attract much attention from the scientific community. Since its discovery, it has been evident that NO has a crucial role in the modulation of vascular tone. Moreover, NO is involved in multiple signal transduction pathways thus contributing to the regulation of many cellular functions. NO effects can be either dependent or independent on cGMP, and rely also upon several mechanisms such as the amount of NO, the compartmentalization of the enzymes responsible for its biosynthesis (NOS), and the local redox conditions. Several evidences highlighted the correlation among adrenoreceptors activity, vascular redox status and NO bioavailability. It was suggested a possible crosstalk between NO and oxidative stress hallmarks in the endothelium function and adaptation, and in sympathetic vasoconstriction control. Adrenergic vasoconstriction is a balance between a direct vasoconstrictive effect on smooth muscle and an indirect vasorelaxant action caused by α2- and β-adrenergic endothelial receptor-triggered NO release. An increased oxidative stress and a reduction of NO bioavailability shifts this equilibrium causing the enhanced vascular adrenergic responsiveness observed in hypertension. The activity of NOS contributes to manage the adrenergic pathway, thus supporting the idea that the endothelium might control or facilitate β-adrenergic effects on the vessels and the polymorphic variants in β2-receptors and NOS isoforms could influence aging, some pathological conditions and individual responses to drugs. This seems to be dependent, almost in part, on differences in the control of vascular tone exerted by NO. Given its involvement in such important mechanisms, the NO pathway is implicated in aging process and in both cardiovascular and non-cardiovascular conditions. Thus, it is essential to pinpoint NO involvement in the regulation of vascular tone for the effective clinical/therapeutic management of cardiovascular diseases (CVD).
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Affiliation(s)
- Valeria Conti
- Department of Medicine and Surgery, University of Salerno Baronissi, Italy
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63
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Bertera FM, Santa-Cruz DM, Balestrasse KB, Gorzalczany SB, Höcht C, Taira CA, Polizio AH. Tempol-nebivolol therapy potentiates hypotensive effect increasing NO bioavailability and signaling pathway. Free Radic Res 2013; 48:109-18. [PMID: 24074298 DOI: 10.3109/10715762.2013.845294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nebivolol is a third generation beta blocker with endothelial nitric oxide synthase (eNOS) agonist properties. Considering the role of reactive oxygen species (ROS) in the uncoupling of eNOS, we hypothesized that the preadministration of an antioxidant as tempol, could improve the hypotensive response of nebivolol in normotensive animals increasing the nitric oxide (NO) bioavailability by a reduction of superoxide (O2(•-)) basal level production in the vascular tissue. Male Sprague Dawley rats were given tap water to drink (control group) or tempol (an antioxidant scavenger of superoxide) for 1 week. After 1 week, Nebivolol, at a dose of 3 mg/kg, was injected intravenously to the control group or to the tempol-treated group. Mean arterial pressure, heart rate, and blood pressure variability were evaluated in the control, tempol, nebivolol, and tempol nebivolol groups, as well as, the effect of different inhibitor as Nβ-nitro-l-arginine methyl ester (L-NAME, a Nitric oxide synthase blocker) or glybenclamide, a KATP channel inhibitor. Also, the expression of α,β soluble guanylate cyclase (sGC), phospho-eNOS, and phospho-vasodilator-stimulated phosphoprotein (P-VASP) were evaluated by Western Blot and cyclic guanosine monophosphate (cGMP) levels by an enzyme-linked immunosorbent assay (ELISA) commercial kit assay. We showed that pretreatment with tempol in normotensive rats produces a hypotensive response after nebivolol administration through an increase in the NO bioavailability and sGC, improving the NO/cGMP/protein kinase G (PKG) pathway compared to that of the nebivolol group. We demonstrated that tempol preadministration beneficiates the response of a third-generation beta blocker with eNOS stimulation properties, decreasing the basal uncoupling of eNOS, and improving NO bioavailability. Our results clearly open a possible new strategy therapeutic for treating hypertension.
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Affiliation(s)
- F M Bertera
- Department of Pharmacology, University of Buenos Aires , Buenos Aires , Argentina
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64
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Ying WZ, Aaron KJ, Sanders PW. Transforming growth factor-β regulates endothelial function during high salt intake in rats. Hypertension 2013; 62:951-6. [PMID: 24041947 DOI: 10.1161/hypertensionaha.113.01835] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Previous studies have demonstrated that an increase in dietary NaCl (salt) intake stimulated endothelial cells to produce transforming growth factor-β (TGF-β). The intent of the present study was to determine the functional significance of increased TGF-β on endothelial cell function. Young Sprague-Dawley rats were fed diets containing 0.3 or 8.0% NaCl for 2 days before treatment with a specific inhibitor of the TGF-β receptor I/activin receptor-like kinase 5 kinase, or vehicle for another 2 days. At day 4 of study, endothelial phosphorylated Smad2 (S465/467) increased and phosphatase and tensin homologue deleted on chromosome 10 (PTEN) levels decreased in the high-salt-treated rats. In addition, phosphorylated Akt (S473) and phosphorylation of the endothelial isoform of NO synthase (NOS3) at S1177 increased. Treatment with the TGF-β receptor I/activin receptor-like kinase 5 inhibitor reduced Smad2 phosphorylation to levels observed in rats on the low-salt diet and prevented the downstream signaling events induced by the high-salt diet. In human umbilical vein endothelial cells, reduction in PTEN levels increased phosphorylated Akt and NOS3. Treatment of macrovascular endothelial cells with TGF-β1 increased phosphorylated NOS3 and the concentration of NO metabolites in the medium but had no effect on either of these variables in cells pretreated with small interfering RNA directed against PTEN. Thus, during high salt intake, an increase in TGF-β directly promoted a reduction in endothelial PTEN levels, which in turn regulated Akt activation and NOS3 phosphorylation. This effect closes a feedback loop that potentially mitigates the effect of TGF-β on the vasculature.
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Affiliation(s)
- Wei-Zhong Ying
- Division of Nephrology/Department of Medicine, 642 Lyons-Harrison Research Bldg, 1530 Third Ave, South, University of Alabama at Birmingham, Birmingham, AL 35294-0007.
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Taylor SY, Dixon HM, Yoganayagam S, Price N, Lang D. Folic acid modulates eNOS activity via effects on posttranslational modifications and protein-protein interactions. Eur J Pharmacol 2013; 714:193-201. [PMID: 23796957 PMCID: PMC3769861 DOI: 10.1016/j.ejphar.2013.05.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 05/10/2013] [Accepted: 05/24/2013] [Indexed: 02/07/2023]
Abstract
Folic acid enhances endothelial function and improves outcome in primary prevention of cardiovascular disease. The exact intracellular signalling mechanisms involved remain elusive and were therefore the subject of this study. Particular focus was placed on folic acid-induced changes in posttranslational modifications of endothelial nitric oxide synthase (eNOS). Cultured endothelial cells were exposed to folic acid in the absence or presence of phosphatidylinositol-3' kinase/Akt (PI3K/Akt) inhibitors. The phosphorylation status of eNOS was determined via western blotting. The activities of eNOS and PI3K/Akt were evaluated. The interaction of eNOS with caveolin-1, Heat-Shock Protein 90 and calmodulin was studied using co-immunoprecipitation. Intracellular localisation of eNOS was investigated using sucrose gradient centrifugation and confocal microscopy. Folic acid promoted eNOS dephosphorylation at negative regulatory sites, and increased phosphorylation at positive regulatory sites. Modulation of phosphorylation status was concomitant with increased cGMP concentrations, and PI3K/Akt activity. Inhibition of PI3K/Akt revealed specific roles for this kinase pathway in folic acid-mediated eNOS phosphorylation. Regulatory protein and eNOS protein associations were altered in favour of a positive regulatory effect in the absence of bulk changes in intracellular eNOS localisation. Folic acid-mediated eNOS activation involves the modulation of eNOS phosphorylation status at multiple residues and positive changes in important protein-protein interactions. Such intracellular mechanisms may in part explain improvements in clinical vascular outcome following folic acid treatment.
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Affiliation(s)
| | | | | | | | - Derek Lang
- Department of Pharmacology, Therapeutics & Toxicology, Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Heath Park Campus, Cardiff CF14 4XN, UK
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Ruan L, Torres CM, Buffett RJ, Kennard S, Fulton D, Venema RC. Calcineurin-mediated dephosphorylation of eNOS at serine 116 affects eNOS enzymatic activity indirectly by facilitating c-Src binding and tyrosine 83 phosphorylation. Vascul Pharmacol 2013; 59:27-35. [PMID: 23727078 DOI: 10.1016/j.vph.2013.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 03/18/2013] [Accepted: 05/21/2013] [Indexed: 10/26/2022]
Abstract
It has been shown previously that phosphorylation of the endothelial nitric oxide synthase (eNOS) at serine 116 (S116) under basal conditions suppresses eNOS enzymatic activity in endothelial cells. It has also been shown that vascular endothelial growth factor (VEGF) treatment of endothelial cells produces a rapid S116 dephosphorylation, which is blocked by the calcineurin inhibitor, cyclosporin A (CsA). In this study, we show that activation of eNOS in response to a variety of other eNOS-activating agonists and the cytosolic calcium-elevating agent, thapsigargin also involves CsA-inhibitable S116 dephosphorylation. Studies with the purified eNOS enzyme also demonstrate that neither mimicking phosphorylation at S116 nor phosphorylation of the purified enzyme at S116 in vitro has any effect on enzymatic activity. Phospho-mimicking, however, does interfere with the interaction of eNOS with c-Src, an interaction which is known to activate eNOS by phosphorylation at tyrosine 83 (Y83). Agonist-stimulated eNOS-Src complex formation, as well as agonist-stimulated Y83 phosphorylation, are blocked by calcineurin inhibition by CsA and by a cell-permeable calcineurin inhibitory peptide. Taken together, these data suggest a mechanism of eNOS regulation whereby calcineurin-mediated dephosphorylation of eNOS at S116 affects eNOS enzymatic activity indirectly, rather than directly, by facilitating c-Src binding and Y83 phosphorylation.
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Affiliation(s)
- Ling Ruan
- Vascular Biology Center, Medical College of Georgia, Georgia Regents University, 1459 Laney Walker Blvd., Augusta, GA 30912, USA
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Noda K, Hosoya M, Nakajima S, Ohashi J, Fukumoto Y, Shimokawa H. Anti-atherogenic effects of the combination therapy with olmesartan and azelnidipine in diabetic apolipoprotein E-deficient mice. TOHOKU J EXP MED 2013; 228:305-15. [PMID: 23124103 DOI: 10.1620/tjem.228.305] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Many studies have aimed to identify anti-atherogenic agents in cardiovascular medicine. We have recently demonstrated that the combination therapy with olmesartan (OLM), an angiotensin II receptor blocker, and azelnidipine (AZL), a dihydroprydine calcium-channel blocker, improves endothelial function in diabetic Apolipoprotein-deficient (ApoE(-/-)) mice. In the present study, we examined whether this combination therapy also inhibits atherosclerosis in mice. We used male control and streptozocin-induced diabetic ApoE(-/-) mice. Diabetic ApoE(-/-) mice were orally treated for 5 weeks with vehicle (Untreated), OLM (30 mg/kg/day), AZL (10 mg/kg/day), their combination (OLM+AZL), or hydralazine (HYD, 5 mg/kg/day) as an antihypertensive control. At 5 weeks, systolic blood pressure was significantly elevated in Untreated but was normalized in OLM+AZL and HYD. The atherosclerosis area in the thoracic aorta, perivascular fibrosis and medial thickness of the coronary arteries were increased in Untreated and were ameliorated in OLM+AZL but not in HYD. Staining with a fluorescent probe dihydroethidium showed that production of reactive oxygen species was increased in Untreated, and ameliorated in OLM+AZL. Consistent with these findings, macrophage infiltration in the kidney and the expression of receptor for advanced glycation end-products in the heart, kidney and liver were increased in Untreated and were all ameliorated in OLM+AZL, associated with up-regulation of endothelial NO syntheses (eNOS). In conclusion, the combination therapy with OLM and AZL exerts anti-atherogenic effect in diabetic ApoE(-/-) mice through suppression of oxidative stress and activation of eNOS, independent of its blood pressure-lowering effects. Clinically, this combination therapy may be useful for patients with hypertension, hyperlipidemia and diabetes.
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Affiliation(s)
- Kazuki Noda
- Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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Hu LS, George J, Wang JH. Current concepts on the role of nitric oxide in portal hypertension. World J Gastroenterol 2013; 19:1707-1717. [PMID: 23555159 PMCID: PMC3607747 DOI: 10.3748/wjg.v19.i11.1707] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 09/13/2012] [Accepted: 12/06/2012] [Indexed: 02/06/2023] Open
Abstract
Portal hypertension (PHT) is defined as a pathological increase in portal venous pressure and frequently accompanies cirrhosis. Portal pressure can be increased by a rise in portal blood flow, an increase in vascular resistance, or the combination. In cirrhosis, the primary factor leading to PHT is an increase in intra-hepatic resistance to blood flow. Although much of this increase is a mechanical consequence of architectural disturbances, there is a dynamic and reversible component that represents up to a third of the increased vascular resistance in cirrhosis. Many vasoactive substances contribute to the development of PHT. Among these, nitric oxide (NO) is the key mediator that paradoxically regulates the sinusoidal (intra-hepatic) and systemic/splanchnic circulations. NO deficiency in the liver leads to increased intra-hepatic resistance while increased NO in the circulation contributes to the hyperdynamic systemic/splanchnic circulation. NO mediated-angiogenesis also plays a role in splanchnic vasodilation and collateral circulation formation. NO donors reduce PHT in animals models but the key clinical challenge is the development of an NO donor or drug delivery system that selectively targets the liver.
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Pires AL, Pinho M, Alves BS, Pinho S, Sena C, Seica RM, Leite-Moreira AF. Reverse myocardial effects of intermedin in pressure-overloaded hearts: role of endothelial nitric oxide synthase activity. J Physiol 2013; 591:677-87. [PMID: 23165766 PMCID: PMC3577549 DOI: 10.1113/jphysiol.2012.240812] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 11/14/2012] [Indexed: 11/08/2022] Open
Abstract
Intermedin (IMD) is a cardiac peptide synthesized in a prepro form, which undergoes a series of proteolytic cleavages and amidations to yield the active forms of 47 (IMD(1-47)) and 40 amino acids (IMD(8-47)). There are several lines of evidence of increased IMD expression in rat models of cardiac pathologies, including congestive heart failure and ischaemia; however, its myocardial effects upon cardiac disease remain unexplored. With this in mind, we investigated the direct effects of increasing concentrations of IMD(1-47) (10(-10) to10(-6) m) on contraction and relaxation of left ventricular (LV) papillary muscles from two rat models of chronic pressure overload, one induced by transverse aortic constriction (TAC), the other by nitric oxide (NO) deficiency due to chronic NO synthase inhibition (NG-nitro-l-arginine, l-NAME), and respective controls (Sham and Ctrl). In TAC and l-NAME rats, exogenous administration of IMD(1-47) elicited concentration-dependent positive inotropic and lusitropic effects. By contrast, in Sham and Ctrl rats, IMD(1-47) induced a negative inotropic response without a significant effect on relaxation. Both TAC and l-NAME rats presented LV hypertrophy, elevated LV systolic pressures, preserved systolic function and elevated peroxynitrite levels. In the normal myocardium (Ctrl and Sham), IMD(1-47) induced a 3-fold increase of endothelial nitric oxide synthase (eNOS) phosphorylation at Ser(1177), indicating enhanced eNOS activity. In TAC and l-NAME rats, eNOS phosphorylation was increased at baseline, and its response to IMD(1-47) was blunted. In addition, the distinct myocardial response to IMD(1-47) was accompanied by distinct subcellular mechanisms. While in Sham rats the addition of IMD(1-47) induced the phosphorylation of cardiac troponin I due to NO/cGMP activation, in TAC rats IMD(1-47) induced phospholamban phosphorylation possibly associated with cAMP/protein kinase A activation. Therefore, we demonstrated for the first time a reversed myocardial response to IMD(1-47) neurohumoral stimulation due to impairment of eNOS activation in TAC and l-NAME rats. These results not only reveal the distinct myocardial effects and subcellular mechanisms for IMD(1-47) in normal and hypertrophic hearts, but also highlight the potential pathophysiological relevance of cardiac endothelial dysfunction in neurohumoral myocardial action.
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Affiliation(s)
- Ana Luísa Pires
- Department of Physiology and Cardiothoracic Surgery, Cardiovascular R&D Unit, Faculty of Medicine, University of Porto, Portugal
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Ladage D, Braunroth C, Lenzen E, Berghöfer S, Graf C, Bloch W, Brixius K. Influence of intermittent hypoxia interval training on exercise-dependent erythrocyte NOS activation and blood pressure in diabetic patients. Can J Physiol Pharmacol 2012; 90:1591-8. [DOI: 10.1139/y2012-138] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NOS-activation in erythrocytes (eryNOS) is impaired in patients suffering from type 2 diabetes. We investigated the effect of physical exercise on eryNOS activation and whether 6 week hypoxia interval training may alter this process. Male patients with diabetes mellitus type 2 (NIDDM, n = 12; age, 61.3 ± 8.4 years; BMI, 29.8 ± 3.7 kg/m2) underwent physical exercise training before and after 6 week hypoxia interval training. Training was conducted 4 times per week for 90 min at 15.4–12.7 Vol% of inspired oxygen. Vital parameters were recorded. Before hypoxia intervention, eryNOS phosphorylation at serine1177decreased significantly during exercise (basal 17.4 ± 12.0 compared with exercise 8.4 ± 9.2 arbitrary grey values (arGV); P < 0.05). After 6 weeks of hypoxia intervention, eryNOS–pSer1177(2.2 ± 2.5 arGV) was significantly lower at baseline. Ergometry showed an increase (7.6 ± 3.0 arGV; P < 0.05) followed by a decrease to almost baseline levels after 30 min (3.8 ± 1.5 arGV). Maximal exercise capacity and O2-uptake ([Formula: see text] max) increased significantly. The effects were independent from exercise-induced elevation of blood pressure. Exercise-dependent eryNOS phosphorylation at serine1177was increased similar to that described for the endothelium in diabetic patients. EryNOS dysregulation was partially restored after intermittent hypoxia training.
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Affiliation(s)
- Dennis Ladage
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
- Department III of Internal Medicine, University Hospital Cologne, Cologne, Germany
| | - Christian Braunroth
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
| | - Edward Lenzen
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
| | - Sandra Berghöfer
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
| | - Christine Graf
- Department of Preventive and Rehabilitative Sport Medicine, Institute of Cardiovascular Research and Sport Medicine, German Sport University Cologne, Cologne, Germany
| | - Wilhelm Bloch
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
| | - Klara Brixius
- Institute for Cardiovascular Research and Sport Medicine, Department of Molecular and Cellular Sport Medicine, German Sport University Cologne, Am Sportpark 6, 50933 Cologne, Germany
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Ying WZ, Aaron KJ, Sanders PW. Effect of aging and dietary salt and potassium intake on endothelial PTEN (Phosphatase and tensin homolog on chromosome 10) function. PLoS One 2012; 7:e48715. [PMID: 23144940 PMCID: PMC3492426 DOI: 10.1371/journal.pone.0048715] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 09/28/2012] [Indexed: 11/19/2022] Open
Abstract
Aging promotes endothelial dysfunction, defined as a reduction in bioavailable nitric oxide (NO) produced by the endothelial isoform of nitric oxide synthase (NOS3). This enzyme is critically regulated by phosphorylation by protein kinase B (Akt), which in turn is regulated by the lipid phosphatase, PTEN. The present series of studies demonstrated a reduction in bioavailable NO as the age of rats increased from 1 to 12 months. At 12 months of age, rats no longer demonstrated increases in phosphorylated NOS3 in response to high dietary salt intake. Endothelial cell levels of PTEN increased with age and became refractory to change with increased salt intake. In contrast to the reduction in NO production, endothelial cell production of transforming growth factor-ß (TGF-ß) relative to NO increased progressively with age. In macrovascular endothelial cells, PTEN was regulated in a dose-dependent fashion by TGF-ß, which was further regulated by extracellular [KCl]. When combined with prior studies, the present series of experiments suggested an integral role for PTEN in endothelial cell pathobiology of aging and an important mitigating function of TGF-ß in endothelial PTEN regulation. The findings further supported a role for diet in affecting vascular function through the production of TGF-ß and NO.
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Affiliation(s)
- Wei-Zhong Ying
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Center for Free Radical Biology, Center for Aging, and Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Kristal J. Aaron
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Center for Free Radical Biology, Center for Aging, and Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Paul W. Sanders
- Division of Nephrology, Department of Medicine, Nephrology Research and Training Center, Center for Free Radical Biology, Center for Aging, and Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
- Department of Veterans Affairs Medical Center, Birmingham, Alabama, United States of America
- * E-mail:
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Increased caveolae density and caveolin-1 expression accompany impaired NO-mediated vasorelaxation in diet-induced obesity. Histochem Cell Biol 2012; 139:309-21. [DOI: 10.1007/s00418-012-1032-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/11/2012] [Indexed: 01/24/2023]
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Niu X, Watts VL, Cingolani OH, Sivakumaran V, Leyton-Mange JS, Ellis CL, Miller KL, Vandegaer K, Bedja D, Gabrielson KL, Paolocci N, Kass DA, Barouch LA. Cardioprotective effect of beta-3 adrenergic receptor agonism: role of neuronal nitric oxide synthase. J Am Coll Cardiol 2012; 59:1979-87. [PMID: 22624839 DOI: 10.1016/j.jacc.2011.12.046] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 11/07/2011] [Accepted: 12/01/2011] [Indexed: 01/08/2023]
Abstract
OBJECTIVES The aim of this study was to determine whether activation of β3-adrenergic receptor (AR) and downstream signaling of nitric oxide synthase (NOS) isoforms protects the heart from failure and hypertrophy induced by pressure overload. BACKGROUND β3-AR and its downstream signaling pathways are recognized as novel modulators of heart function. Unlike β1- and β2-ARs, β3-ARs are stimulated at high catecholamine concentrations and induce negative inotropic effects, serving as a "brake" to protect the heart from catecholamine overstimulation. METHODS C57BL/6J and neuronal NOS (nNOS) knockout mice were assigned to receive transverse aortic constriction (TAC), BRL37344 (β3 agonist, BRL 0.1 mg/kg/h), or both. RESULTS Three weeks of BRL treatment in wild-type mice attenuated left ventricular dilation and systolic dysfunction, and partially reduced cardiac hypertrophy induced by TAC. This effect was associated with increased nitric oxide production and superoxide suppression. TAC decreased endothelial NOS (eNOS) dimerization, indicating eNOS uncoupling, which was not reversed by BRL treatment. However, nNOS protein expression was up-regulated 2-fold by BRL, and the suppressive effect of BRL on superoxide generation was abrogated by acute nNOS inhibition. Furthermore, BRL cardioprotective effects were actually detrimental in nNOS(-/-) mice. CONCLUSIONS These results are the first to show in vivo cardioprotective effects of β3-AR-specific agonism in pressure overload hypertrophy and heart failure, and support nNOS as the primary downstream NOS isoform in maintaining NO and reactive oxygen species balance in the failing heart.
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Affiliation(s)
- Xiaolin Niu
- Department of Cardiology, Tangdu Hospital, The Fourth Military Medical University, Xinsi Road, Xi'an, China. [corrected]
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Yang D, Xie P, Liu Z. Ischemia/reperfusion-induced MKP-3 impairs endothelial NO formation via inactivation of ERK1/2 pathway. PLoS One 2012; 7:e42076. [PMID: 22848708 PMCID: PMC3407110 DOI: 10.1371/journal.pone.0042076] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 07/02/2012] [Indexed: 02/05/2023] Open
Abstract
Mitogen-activated protein kinase phosphatases (MKPs) are a family of dual-specificity phosphatases. Endothelial cells express multiple MKP family members, such as MKP-3. However, the effects of MKP-3 on endothelial biological processes have not yet been fully elucidated. Here, we address the association between MKP-3 and endothelial Nitric oxide (NO) formation under ischemia/reperfusion (IS/RP) condition. Human umbilical vein endothelial cells (HUVECs) were subjected to IS/RP treatment. The MKP-3 expression and NO formation were examined. IS/RP induced endothelial MKP-3 expression and inhibited eNOS expression and NO formation, accompanied by an increase of endothelial apoptosis. The siRNA experiments showed that MKP-3 was an important mediator in impairing eNOS expression and NO production in endothelial cells. Transfection of HUVECs with constitutively active ERK plasmids suggested that the above mentioned effect of MKP-3 was via inactivation of ERK1/2 pathway. Furthermore, impairment of eNOS expression was restored by treatment of histone deacetylase (HDAC) inhibitor and related to histone deacetylation and recruitment of HDAC1 to the eNOS promoter. Finally, Salvianolic acid A (SalA) markedly attenuated induction of MKP-3 and inhibition of eNOS expression and NO formation under endothelial IS/RP condition. Overall, these results for the first time demonstrated that IS/RP inhibited eNOS expression by inactivation of ERK1/2 and recruitment of HDAC1 to the gene promoter, leading to decreased NO formation through a MKP-3-dependent mechanism in endothelial cells, and SalA has therapeutic significance in protecting endothelial cells from impaired NO formation in response to IS/RP.
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Affiliation(s)
- Dan Yang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
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Wang Z, Kim JI, Frilot N, Daaka Y. Dynamin2 S-nitrosylation regulates adenovirus type 5 infection of epithelial cells. J Gen Virol 2012; 93:2109-2117. [PMID: 22791607 DOI: 10.1099/vir.0.042713-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dynamin2 is a large GTPase that regulates vesicle trafficking, and the GTPase activity of dynamin2 is required for the multistep process of adenovirus infection. Activity of dynamin2 may be regulated by post-translational phosphorylation and S-nitrosylation modifications. In this study, we demonstrate a role for dynamin2 S-nitrosylation in adenovirus infection of epithelial cells. We show that adenovirus serotype 5 (Ad5) infection augments production of nitric oxide (NO) in epithelial cells and causes the S-nitrosylation of dynamin2, mainly on cysteine 86 (C86) and 607 (C607) residues. Forced overexpression of dynamin2 bearing C86A and/or C607A mutations decreases Ad5 infection. Diminishing NO synthesis by RNAi-induced knockdown of endogenous endothelial NO synthase (eNOS) expression attenuates virus infection of target cells. Ad5 infection promotes the kinetically dynamic S-nitrosylation of dynamin2 and eNOS: there is a rapid decrease in eNOS S-nitrosylation and a concomitant increase in the dynamin2 S-nitrosylation. These results support the hypothesis that dynamin2 S-nitrosylation following eNOS activation facilitates adenovirus infection of host epithelial cells.
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Affiliation(s)
- Zhimin Wang
- Department of Urology and Prostate Disease Center, University of Florida, Gainesville, FL 32610, USA
| | - Jae Il Kim
- Department of Urology and Prostate Disease Center, University of Florida, Gainesville, FL 32610, USA
| | - Nicole Frilot
- Department of Pathology, Georgia Health Sciences University, Augusta, GA 30912, USA
| | - Yehia Daaka
- Department of Anatomy and Cell Biology, University of Florida, Gainesville, FL 32610, USA.,Department of Urology and Prostate Disease Center, University of Florida, Gainesville, FL 32610, USA
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Li XD, Cheng YT, Yang YJ, Meng XM, Zhao JL, Zhang HT, Wu YJ, You SJ, Wu YL. PKA-mediated eNOS phosphorylation in the protection of ischemic preconditioning against no-reflow. Microvasc Res 2012; 84:44-54. [DOI: 10.1016/j.mvr.2012.04.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 02/23/2012] [Accepted: 04/06/2012] [Indexed: 10/28/2022]
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77
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Li ZL, Liu JC, Liu SB, Li XQ, Yi DH, Zhao MG. Improvement of vascular function by acute and chronic treatment with the GPR30 agonist G1 in experimental diabetes mellitus. PLoS One 2012; 7:e38787. [PMID: 22679517 PMCID: PMC3367949 DOI: 10.1371/journal.pone.0038787] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 05/10/2012] [Indexed: 12/27/2022] Open
Abstract
The G-protein coupled estrogen receptor 30 (GPR30) is a seven-transmembrane domain receptor that mediates rapid estrogen responses in a wide variety of cell types. This receptor is highly expressed in the cardiovascular system, and exerts vasodilatory effects. The objective of the present study was to investigate the effects of GPR30 on vascular responsiveness in diabetic ovariectomized (OVX) rats and elucidate the possible mechanism involved. The roles of GPR30 were evaluated in the thoracic aorta and cultured endothelial cells. The GPR30 agonist G1 induced a dose-dependent vasodilation in the thoracic aorta of the diabetic OVX rats, which was partially attenuated by the nitric oxide synthase (NOS) inhibitor, nitro-L-arginine methylester (L-NAME) and the GPR30-selective antagonist G15. Dose-dependent vasoconstrictive responses to phenylephrine were attenuated significantly in the rings of the thoracic aorta following the acute G1 administration in the diabetic OVX rats. This effect of G1 was abolished partially by L-NAME and G15. The acute administration of G1 increased significantly the eNOS activity and the concentration of NO in the endothelial cells exposed to high glucose. G1 treatment induced an enhanced endothelium-dependent relaxation to acetylcholine (Ach) in the diabetic OVX rats. Further examination revealed that G1 induced vasodilation in the diabetic OVX rats by increasing the phosphorylation of eNOS. These findings provide preliminary evidence that GPR30 activation leads to eNOS activation, as well as vasodilation, to a certain degree and has beneficial effects on vascular function in diabetic OVX rats.
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Affiliation(s)
- Zi-lin Li
- Department of Cardiovascular Surgery, Xijing Hospital, School of Pharmacy, Fourth Military Medical University, Xi'an, China
- Department of Cardiothoracic Surgery, PLA 452 Hospital, Chengdu, Sichuan, China
| | - Jin-cheng Liu
- Department of Cardiovascular Surgery, Xijing Hospital, School of Pharmacy, Fourth Military Medical University, Xi'an, China
| | - Shui-bing Liu
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, China
| | - Xiao-qiang Li
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, China
| | - Ding-hua Yi
- Department of Cardiovascular Surgery, Xijing Hospital, School of Pharmacy, Fourth Military Medical University, Xi'an, China
- * E-mail: (DHY); (MGZ)
| | - Ming-gao Zhao
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an, China
- * E-mail: (DHY); (MGZ)
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Cruz JA, Bauer EM, Rodriguez AI, Gangopadhyay A, Zeineh NS, Wang Y, Shiva S, Champion HC, Bauer PM. Chronic hypoxia induces right heart failure in caveolin-1-/- mice. Am J Physiol Heart Circ Physiol 2012; 302:H2518-27. [PMID: 22505641 DOI: 10.1152/ajpheart.01140.2011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Caveolin-1 (Cav-1)-/- mice develop mild pulmonary hypertension as they age. In this study, we sought to determine the effect of chronic hypoxia, an established model of pulmonary hypertension, on young Cav-1-/- mice with no measurable signs of pulmonary hypertension. Exposure of Cav-1-/- mice to chronic hypoxia resulted in an initial rise in right ventricular (RV) systolic pressure (RVSP) similar to wild-type (WT) mice. By three weeks RVSP decreased in the Cav-1-/- mice, whereas it was maintained in WT mice. The drop in RVSP in Cav-1-/- mice was accompanied by decreased cardiac output, increased RV hypertrophy, RV interstitial fibrosis, decreased RV sarco(endo)plasmic reticulum Ca(2+)-ATPase 2a mRNA and decreased RV function compared with WT mice. Importantly, minimal differences were noted in pulmonary vascular remodeling between WT and Cav-1-/- mice, and left ventricular function was normal in hypoxic Cav-1-/- mice. Mechanistically, increased endothelial nitric oxide synthase uncoupling and increased tyrosine nitration of protein kinase G were detected in the RV of Cav-1-/- mice. These hemodynamic, histological, and molecular changes were prevented in Cav-1-/- mice expressing an endothelial-specific Cav-1 transgene or by nitric oxide synthase inhibition. These data suggest that, in Cav-1-/- mice, increased oxidative/nitrosative stress due to endothelial nitric oxide synthase uncoupling modifies the response of the RV to pressure overload, accelerating the deterioration of RV function.
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Affiliation(s)
- J Agustin Cruz
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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79
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Abu-Amara M, Yang SY, Seifalian A, Davidson B, Fuller B. The nitric oxide pathway--evidence and mechanisms for protection against liver ischaemia reperfusion injury. Liver Int 2012; 32:531-43. [PMID: 22316165 DOI: 10.1111/j.1478-3231.2012.02755.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 12/29/2011] [Indexed: 02/13/2023]
Abstract
Ischaemia reperfusion (IR) injury is a clinical entity with a major contribution to the morbidity and mortality of liver surgery and transplantation. A central pathway of protection against IR injury utilizes nitric oxide (NO). Nitric oxide synthase (NOS) enzymes manufacture NO from L-arginine. NO generated by the endothelial NOS (eNOS) isoform protects against liver IR injury, whereas inducible NOS (iNOS)-derived NO may have either a protective or a deleterious effect during the early phase of IR injury, depending on the length of ischaemia, length of reperfusion and experimental model. In late phase hepatic IR injury, iNOS-derived NO plays a protective role. In addition to NOS consumption of L-arginine during NO synthesis, this amino acid may also be metabolized by arginase, an enzyme whose release is increased during prolonged ischaemia, and therefore diverts L-arginine away from NOS metabolism leading to a drop in the rate of NO synthesis. NO most commonly acts through the soluble guanylyl cyclase-cyclic GMP- protein kinase G pathway to ameliorate hepatic IR injury. Both endogenously generated and exogenously administered NO donors protect against liver IR injury. The beneficial effects of NO on liver IR are not, however, universal, and certain conditions, such as steatosis, may influence the protective effects of NO. In this review, the evidence for, and mechanisms of these protective actions of NO are discussed, and areas in need of further research are highlighted.
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Affiliation(s)
- Mahmoud Abu-Amara
- Liver Transplantation and Hepatobiliary Unit, Royal Free Hospital, London, UK
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80
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Predmore BL, Kondo K, Bhushan S, Zlatopolsky MA, King AL, Aragon JP, Grinsfelder DB, Condit ME, Lefer DJ. The polysulfide diallyl trisulfide protects the ischemic myocardium by preservation of endogenous hydrogen sulfide and increasing nitric oxide bioavailability. Am J Physiol Heart Circ Physiol 2012; 302:H2410-8. [PMID: 22467307 DOI: 10.1152/ajpheart.00044.2012] [Citation(s) in RCA: 137] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diallyl trisulfide (DATS), a polysulfide constituent found in garlic oil, is capable of the release of hydrogen sulfide (H(2)S). H(2)S is a known cardioprotective agent that protects the heart via antioxidant, antiapoptotic, anti-inflammatory, and mitochondrial actions. Here, we investigated DATS as a stable donor of H(2)S during myocardial ischemia-reperfusion (MI/R) injury in vivo. We investigated endogenous H(2)S levels, infarct size, postischemic left ventricular function, mitochondrial respiration and coupling, endothelial nitric oxide (NO) synthase (eNOS) activation, and nuclear E2-related factor (Nrf2) translocation after DATS treatment. Mice were anesthetized and subjected to a surgical model of MI/R injury with and without DATS treatment (200 μg/kg). Both circulating and myocardial H(2)S levels were determined using chemiluminescent gas chromatography. Infarct size was measured after 45 min of ischemia and 24 h of reperfusion. Troponin I release was measured at 2, 4, and 24 h after reperfusion. Cardiac function was measured at baseline and 72 h after reperfusion by echocardiography. Cardiac mitochondria were isolated after MI/R, and mitochondrial respiration was investigated. NO metabolites, eNOS phosphorylation, and Nrf2 translocation were determined 30 min and 2 h after DATS administration. Myocardial H(2)S levels markedly decreased after I/R injury but were rescued by DATS treatment (P < 0.05). DATS administration significantly reduced infarct size per area at risk and per left ventricular area compared with control (P < 0.001) as well as circulating troponin I levels at 4 and 24 h (P < 0.05). Myocardial contractile function was significantly better in DATS-treated hearts compared with vehicle treatment (P < 0.05) 72 h after reperfusion. DATS reduced mitochondrial respiration in a concentration-dependent manner and significantly improved mitochondrial coupling after reperfusion (P < 0.01). DATS activated eNOS (P < 0.05) and increased NO metabolites (P < 0.05). DATS did not appear to significantly induce the Nrf2 pathway. Taken together, these data suggest that DATS is a donor of H(2)S that can be used as a cardioprotective agent to treat MI/R injury.
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Affiliation(s)
- Benjamin L Predmore
- Division of Cardiothoracic Surgery, Department of Surgery, Emory University School of Medicine, Atlanta, Georgia 30308, USA
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81
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Pan L, Hu JL, Wang WJ, Zhang XJ, Wei J, Liu ZD, Zhang YH, Xu HM. Molecular mechanisms of (R,R)ZX-5 on NO synthesis and its anti-angiogenic effect. Int J Mol Sci 2012; 13:2717-2726. [PMID: 22489120 PMCID: PMC3317683 DOI: 10.3390/ijms13032717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2011] [Revised: 02/04/2012] [Accepted: 02/14/2012] [Indexed: 01/16/2023] Open
Abstract
(R,R)ZX-5 is a NO regulatory compound, which could significantly increase choroidal blood flow in New Zealand rabbit. The aim of this paper is to investigate the molecular mechanism of (R,R)ZX-5 promoting NO production. Besides this, we also investigated the antiangiogenic activity of (R,R)ZX-5. Analysis of Western blot showed that (R,R)ZX-5 up-regulated the expression of Akt, p-Akt (Thr473), eNOS and p-eNOS (Ser1177), down-regulated the expression of Cyclin D1 in human retinal endothelial cells and escalated the intracellular free Ca2+ concentration. Additionally, (R,R)ZX-5 inhibited the growth of blood vessels in the chick chorioallantoic membrane model. It is concluded that (R,R)ZX-5 promotes choroidal blood flow through PI3K/Akt-eNOS and Akt-Ca2+-eNOS pathways. Additionally, (R,R)ZX-5 can inhibit angiogenesis.
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Affiliation(s)
- Li Pan
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Jia-Liang Hu
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Wen-Jing Wang
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Xiao-Juan Zhang
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Jin Wei
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Zhen-Dong Liu
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
| | - Yi-Hua Zhang
- Department of Pharmacy, University of China Pharmaceutical, Nanjing 210009, China
- Authors to whom correspondence should be addressed; E-Mails: (H.-M.X.); (Y.-H.Z.); Tel./Fax: +86-025-83271007 (H.-M.X.); +86-025-86635503 (Y.-H.Z.)
| | - Han-Mei Xu
- State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China; E-Mails: (L.P.); (J.-L.H.); (W.-J.W.); (X.-J.Z.); (J.W.); (Z.-D.L.)
- Authors to whom correspondence should be addressed; E-Mails: (H.-M.X.); (Y.-H.Z.); Tel./Fax: +86-025-83271007 (H.-M.X.); +86-025-86635503 (Y.-H.Z.)
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82
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Vascular Targets for Ischemic Stroke Treatment. Transl Stroke Res 2012. [DOI: 10.1007/978-1-4419-9530-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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83
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Park JH, Park M, Byun CJ, Jo I. c-Jun N-terminal kinase 2 phosphorylates endothelial nitric oxide synthase at serine 116 and regulates nitric oxide production. Biochem Biophys Res Commun 2011; 417:340-5. [PMID: 22155232 DOI: 10.1016/j.bbrc.2011.11.112] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2011] [Accepted: 11/21/2011] [Indexed: 10/15/2022]
Abstract
The c-Jun N-terminal kinases (JNKs) belonging to the mitogen-activated protein kinase (MAPK) superfamily play important roles in foam-cell formation, hypercholesterolemia-mediated endothelial dysfunction, and the development of obesity. Although decreased nitric oxide (NO) production via decreased phosphorylation of endothelial NO synthase at serine 1179 (eNOS-Ser(1179)) was reported to be partly involved in JNK2-derived endothelial dysfunction, JNK2 seems likely to be indirectly involved in this signaling pathway. Here, using bovine aortic endothelial cells, we examined whether JNK2 directly phosphorylated eNOS-Ser(116), a putative substrate site for the MAPK superfamily, and this phosphorylation resulted in decreased NO release. JNK inhibitor SP60012 increased NO release in a time- and dose-dependent manner, which was accompanied by increased eNOS-Ser(116) phosphorylation. Purified JNK2 directly phosphorylated eNOS-Ser(116)in vitro. Ectopic expression of dominant negative JNK2 repressed eNOS-Ser(116) phosphorylation and increased NO production. Coimmunoprecipitation and confocal microscopy studies revealed a colocalization of eNOS and JNK2. However, all these observed effects were not manifested when JNK1 probes were used. Overall, this study indicates that JNK2 is a physiological kinase responsible for eNOS-Ser(116) phosphorylation and regulates NO production.
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Affiliation(s)
- Jung-Hyun Park
- Department of Molecular Medicine and Ewha Medical Research Institute, Ewha Womans University Medical School, Seoul, South Korea
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84
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Kornfeld S, Goupille C, Vibet S, Chevalier S, Pinet A, Lebeau J, Tranquart F, Bougnoux P, Martel E, Maurin A, Richard S, Champeroux P, Mahéo K. Reducing endothelial NOS activation and interstitial fluid pressure with n-3 PUFA offset tumor chemoresistance. Carcinogenesis 2011; 33:260-7. [PMID: 22114075 DOI: 10.1093/carcin/bgr274] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The aim of this study was to determine how n-3 polyunsaturated fatty acid (PUFAs) counteracted tumor chemoresistance by restoring a functional vascularization. Rats with chemically induced mammary tumors were divided into two nutritional groups: a control group and a group fed with an n-3 PUFA-enriched diet. Both groups were treated with docetaxel. Functional vascular parameters (ultrasounds, interstitial fluid pressure) were determined for both nutritional groups before (W(0)) and during docetaxel treatment [every 2 h up to 1 week (W(+1)) for interstitial fluid pressure, at W(+1) for Evans blue extravasation and at W(+2) and W(+6) for ultrasounds]. In vitro n-3 PUFA-induced changes in endothelial cell migration, permeability and phosphorylation of endothelial nitric oxide synthase were evaluated using human umbilical vein endothelial cells. Whereas docetaxel stabilized tumor growth in the rat control group, it induced a 50% tumor regression in the n-3 PUFA group. Ultrasounds parameters were consistently lower in the n-3 PUFA group at all time points measured, down to ∼50% at W(+6). A single dose of docetaxel in the n-3 PUFA group markedly reduced interstitial fluid pressure from 2 h after injection up to W(+1) when Evans blue extravasation was increased by 3-fold. A decreased activation of endothelial nitric oxide synthase in tumors of the n-3 PUFA group, and in human umbilical vein endothelial cell cultured with n-3 PUFA, points toward a PUFA-induced disruption of nitric oxide signaling pathway. This normalization of tumor vasculature functions under n-3 PUFA diet indicates that such a supplementation, by improving drug delivery in mammary tumors, could be a complementary clinical strategy to decrease anticancer drug resistance.
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Affiliation(s)
- Sophie Kornfeld
- INSERM U921 Nutrition, Croissance et Cancer Université François Rabelais, Tours, France
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85
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Gangopahyay A, Oran M, Bauer EM, Wertz JW, Comhair SA, Erzurum SC, Bauer PM. Bone morphogenetic protein receptor II is a novel mediator of endothelial nitric-oxide synthase activation. J Biol Chem 2011; 286:33134-40. [PMID: 21808054 DOI: 10.1074/jbc.m111.274100] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Activation of bone morphogenetic protein (BMP) receptor II (BMPRII) promotes pulmonary artery endothelial cell (PAEC) survival, proliferation, and migration. Mutations to BMPRII are associated with the development of pulmonary arterial hypertension (PAH). Endothelial dysfunction, including decreased endothelial nitric-oxide synthase (eNOS) activity and loss of bioactive nitric oxide (NO), plays a prominent role in the development of PAH. We hypothesized that stimulation of BMPRII promotes normal PAEC function by activating eNOS. We report that BMPRII ligands, BMP2 and BMP4, (i) stimulate eNOS phosphorylation at a critical regulatory site, (ii) increase eNOS activity, and (iii) result in canonical changes in eNOS protein-protein interactions. The stimulation of eNOS activity by BMPRII ligands was largely dependent on protein kinase A (PKA) activation, as demonstrated using the PKA inhibitors H89 and myristoylated PKI(6-22) amide. PAEC migration stimulated by BMP2 and BMP4 was inhibited by the NOS inhibitor l-nitroarginine methyl ester, providing functional evidence of eNOS activation. Furthermore, BMP2 and BMP4 failed to stimulate eNOS phosphorylation when BMPRII was knocked down by siRNA. Most important to the pathophysiology of the disease, BMP2 and BMP4 failed to stimulate eNOS phosphorylation in PAECs isolated from patients with mutations in the BMPR2 gene. These data demonstrate a new action of BMPs/BMPRII in the pulmonary endothelium and provide novel mechanistic insight into the pathogenesis of PAH.
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Affiliation(s)
- Archana Gangopahyay
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA
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86
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Sánchez FA, Rana R, González FG, Iwahashi T, Durán RG, Fulton DJ, Beuve AV, Kim DD, Durán WN. Functional significance of cytosolic endothelial nitric-oxide synthase (eNOS): regulation of hyperpermeability. J Biol Chem 2011; 286:30409-30414. [PMID: 21757745 DOI: 10.1074/jbc.m111.234294] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Endothelial NOS (eNOS)-derived NO is a key factor in regulating microvascular permeability. We demonstrated previously that eNOS translocation from the plasma membrane to the cytosol is required for hyperpermeability. Herein, we tested the hypothesis that eNOS activation in the cytosol is necessary for agonist-induced hyperpermeability. To study the fundamental properties of endothelial cell monolayer permeability, we generated ECV-304 cells that stably express cDNA constructs targeting eNOS to the cytosol or plasma membrane. eNOS-transfected ECV-304 cells recapitulate the eNOS translocation and permeability properties of postcapillary venular endothelial cells (Sánchez, F. A., Rana, R., Kim, D. D., Iwahashi, T., Zheng, R., Lal, B. K., Gordon, D. M., Meininger, C. J., and Durán, W. N. (2009) Proc. Natl. Acad. Sci. U.S.A. 106, 6849-6853). We used platelet-activating factor (PAF) as a proinflammatory agonist. PAF activated eNOS by increasing phosphorylation of Ser-1177 and inducing dephosphorylation of Thr-495, increasing NO production, and elevating permeability to FITC-dextran 70 in monolayers of cells expressing wild-type and cytosolic eNOS. PAF failed to increase permeability to FITC-dextran 70 in monolayers of cells transfected with eNOS targeted to the plasma membrane. Interestingly, this occurred despite eNOS Ser-1177 phosphorylation and production of comparable amounts of NO. Our results demonstrate that the presence of eNOS in the cytosol is necessary for PAF-induced hyperpermeability. Our data provide new insights into the dynamics of eNOS and eNOS-derived NO in the process of inflammation.
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Affiliation(s)
- Fabiola A Sánchez
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709; Instituto de Inmunología, Escuela de Medicina, Universidad Austral de Chile, Valdivia 511-0566, Chile
| | - Roshniben Rana
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - Francisco G González
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - Toru Iwahashi
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - Ricardo G Durán
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - David J Fulton
- Department of Pharmacology and Toxicology, Georgia Health Sciences University-Medical College of Georgia, Augusta, Georgia 30912
| | - Annie V Beuve
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - David D Kim
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709
| | - Walter N Durán
- Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey 07101-1709.
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87
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Félétou M. The Endothelium, Part I: Multiple Functions of the Endothelial Cells -- Focus on Endothelium-Derived Vasoactive Mediators. ACTA ACUST UNITED AC 2011. [DOI: 10.4199/c00031ed1v01y201105isp019] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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88
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89
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Dysfunction of human subcutaneous fat arterioles in obesity alone or obesity associated with Type 2 diabetes. Clin Sci (Lond) 2011; 120:463-72. [PMID: 20979575 DOI: 10.1042/cs20100355] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of the present study was to examine the effects of obesity alone and obesity associated with Type 2 diabetes on the structure, vascular reactivity and response to insulin of isolated human subcutaneous fat arterioles; these effects were correlated with the expression of insulin signalling proteins. Periumbilical subcutaneous adipose tissue was explanted during surgery, small arterioles (internal diameter 220 ± 40 μm) were dissected out and investigated by electron microscopy, myography and immunoblotting. Compared with the subcutaneous arterioles of lean subjects, obesity activated the endothelium, enhanced the accumulation of collagen within vascular wall and increased the sensitivity of adrenergic response; obesity also diminished eNOS (endothelial NO synthase) protein expression, NO production, and endothelium-dependent and insulin-induced vasodilatation, as well as the protein expression of both IRS (insulin receptor substrates)-1 and IRS-2 and of the downstream molecules in the insulin signalling pathway, such as PI3K (phosphoinositide 3-kinase), phospho-Akt and Akt. When obesity was associated with Type 2 diabetes, these changes were significantly augmented. In conclusion, obesity alone or obesity associated with Type 2 diabetes alters human periumbilical adipose tissue arterioles in terms of structure, function and biochemsitry, including diminished eNOS expression and reduced levels of IRS-1, IRS-2, PI3K and Akt in the insulin signalling pathway.
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90
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Nitric oxide: role in tumour biology and iNOS/NO-based anticancer therapies. Cancer Chemother Pharmacol 2011; 67:1211-24. [DOI: 10.1007/s00280-011-1654-4] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 04/14/2011] [Indexed: 01/10/2023]
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91
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Steinert JR, Chernova T, Forsythe ID. Nitric oxide signaling in brain function, dysfunction, and dementia. Neuroscientist 2011; 16:435-52. [PMID: 20817920 DOI: 10.1177/1073858410366481] [Citation(s) in RCA: 315] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nitric oxide (NO) is an important signaling molecule that is widely used in the nervous system. With recognition of its roles in synaptic plasticity (long-term potentiation, LTP; long-term depression, LTD) and elucidation of calcium-dependent, NMDAR-mediated activation of neuronal nitric oxide synthase (nNOS), numerous molecular and pharmacological tools have been used to explore the physiology and pathological consequences for nitrergic signaling. In this review, the authors summarize the current understanding of this subtle signaling pathway, discuss the evidence for nitrergic modulation of ion channels and homeostatic modulation of intrinsic excitability, and speculate about the pathological consequences of spillover between different nitrergic compartments in contributing to aberrant signaling in neurodegenerative disorders. Accumulating evidence points to various ion channels and particularly voltage-gated potassium channels as signaling targets, whereby NO mediates activity-dependent control of intrinsic neuronal excitability; such changes could underlie broader mechanisms of synaptic plasticity across neuronal networks. In addition, the inability to constrain NO diffusion suggests that spillover from endothelium (eNOS) and/or immune compartments (iNOS) into the nervous system provides potential pathological sources of NO and where control failure in these other systems could have broader neurological implications. Abnormal NO signaling could therefore contribute to a variety of neurodegenerative pathologies such as stroke/excitotoxicity, Alzheimer's disease, multiple sclerosis, and Parkinson's disease.
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Affiliation(s)
- Joern R Steinert
- Neurotoxicity at the Synaptic Interface, MRC Toxicology Unit, University of Leicester, Leicester, UK
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92
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Nanni S, Grasselli A, Benvenuti V, Aiello A, Pantisano V, Re A, Gaetano C, Capogrossi MC, Bacchetti S, Pontecorvi A, Farsetti A. The role of nuclear endothelial nitric oxide synthase in the endothelial and prostate microenvironments. Horm Mol Biol Clin Investig 2011; 5:91-6. [DOI: 10.1515/hmbci.2011.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 11/15/2022]
Abstract
AbstractThis review is based on novel observations from our laboratory on the nuclear translocation and functional role of endothelial nitric oxide synthase (eNOS) in endothelial and prostate cancer (PCa) epithelial cells. Nitric oxide (NO), the product of eNOS, is a free radical involved in the physiology and pathophysiology of living organisms and in a variety of biological processes including the maintenance of vascular homeostasis. Of relevance in this context is the role that estrogens play in the apoptotic process and the migration of endothelial cells through the regulation of target genes such as eNOS itself. It has been shown that both estrogen and NO signaling, mediated respectively by the estrogen receptors (ERs) and eNOS, can strongly counteract endothelial senescence through a common effector, the catalytic subunit of human telomerase. Therefore, this protein has been identified as a key molecule in the aging process which, intriguingly, is considered the only risk factor in the development of PCa and one of the major determinants of cardiovascular diseases. Indeed, in both these contexts we have defined a molecular mechanism involving activation of eNOS and hypoxia-inducible factors in association with ERβ that characterizes the most aggressive form of PCa or influences endothelial cell differentiation. Altogether these data led us to postulate that activation of eNOS is a crucial requirement for the delaying of endothelial senescence as well as for the acquisition of androgen-independence and for tumor progression in the prostate microenvironment.
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93
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Palomares SM, Cipolla MJ. Vascular Protection Following Cerebral Ischemia and Reperfusion. ACTA ACUST UNITED AC 2011; 2011. [PMID: 22102980 DOI: 10.4172/2155-9562.s1-004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite considerable research that has contributed to a better understanding of the pathophysiology of stroke, translation of this knowledge into effective therapies has largely failed. The only effective treatment for ischemic stroke is rapid recanalization of an occluded vessel by dissolving the clot with tissue plasminogen activator (tPA). However, stroke adversely affects vascular function as well that can cause secondary brain injury and limit treatment that depends on a patent vasculature. In middle cerebral arteries (MCA), ischemia/reperfusion (I/R) cause loss of myogenic tone, vascular paralysis, and endothelial dysfunction that can lead to loss of autoregulation. In contrast, brain parenchymal arterioles retain considerable tone during I/R that likely contributes to expansion of the infarct into the penumbra. Microvascular dysregulation also occurs during ischemic stroke that causes edema and hemorrhage, exacerbating the primary insult. Ischemic injury of vasculature is progressive with longer duration of I/R. Early postischemic reperfusion has beneficial effects on stroke outcome but can impair vascular function and exacerbate ischemic injury after longer durations of I/R. This review focuses on current knowledge on the effects of I/R on the structure and function of different vascular segments in the brain and highlight some of the more promising targets for vascular protection.
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Affiliation(s)
- Sara Morales Palomares
- Departments of Neurology, Obstetrics, Gynecology & Reproductive Sciences and Pharmacology, University of Vermont, Burlington, Vermont
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94
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95
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Oyama N, Yagita Y, Sasaki T, Omura-Matsuoka E, Terasaki Y, Sugiyama Y, Sakoda S, Kitagawa K. An angiotensin II type 1 receptor blocker can preserve endothelial function and attenuate brain ischemic damage in spontaneously hypertensive rats. J Neurosci Res 2010; 88:2889-98. [PMID: 20544833 DOI: 10.1002/jnr.22441] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hypertension reduces endothelial nitric oxide synthase (eNOS) expression and leads to endothelial dysfunction. However, few studies have demonstrated the influences of hypertension on eNOS function in the cerebral cortex. The present study investigates the influences of hypertension on endothelial function in the cerebral cortex and the protective effects of antihypertensive agents against brain ischemia through the preservation of endothelial function. Five- and ten-week-old male Wistar rats and spontaneously hypertensive rats (SHR) were used for experiments. Five-week-old SHR received olmesartan, hydralazine, or vehicle for 5 weeks in drinking water. eNOS activation in the cerebral cortex was evaluated by analyzing levels of total and Ser(1177)-phosphorylated eNOS protein by Western blot. Blood pressure of 10-week-old SHR without treatment was clearly high, and the ratio of phospho-eNOS/total eNOS protein was significantly low. Five-week treatment with olmesartan or hydralazine suppressed the elevation of blood pressure and the reduction of phosphorylated eNOS-Ser(1177) in SHR, and olmesartan was more effective in maintaining phosphorylation of eNOS-Ser(1177) than hydralazine. To assess the contribution of eNOS to maintaining cerebral blood flow (CBF), we monitored CBF by laser-Doppler flowmetry after L-N(5)-(1-iminoethyl)ornithine (L-NIO) infusion. CBF response to L-NIO was preserved in olmesartan-treated SHR but not in hydralazine-treated SHR. Furthermore, infarct volume 48 hr after transient focal brain ischemia in olmesartan-treated SHR was significantly reduced compared with vehicle-treated SHR. These findings indicate that chronic prehypertensive treatment with olmesartan could attenuate brain ischemic injury through the maintenance of endothelial function in the cerebral cortex in SHR.
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Affiliation(s)
- Naoki Oyama
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan.
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96
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Erdogdu O, Nathanson D, Sjöholm A, Nyström T, Zhang Q. Exendin-4 stimulates proliferation of human coronary artery endothelial cells through eNOS-, PKA- and PI3K/Akt-dependent pathways and requires GLP-1 receptor. Mol Cell Endocrinol 2010; 325:26-35. [PMID: 20452396 DOI: 10.1016/j.mce.2010.04.022] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 04/20/2010] [Accepted: 04/27/2010] [Indexed: 12/20/2022]
Abstract
Endothelial cells have a robust capacity to proliferate and participate in angiogenesis, which underlies the maintenance of intimal layer integrity. We previously showed the presence of the GLP-1 receptor in human coronary artery endothelial cells (HCAECs) and the ameliorative actions of GLP-1 on endothelial dysfunction in type 2 diabetic patients. Here, we have studied the effect of exendin-4 on cell proliferation and its underlying mechanisms in HCAECs. Incubation of HCAECs with exendin-4 resulted in a dose-dependent increase in DNA synthesis and an increased cell number, associated with an enhanced eNOS and Akt activation, which were inhibited by PKA, PI3K, Akt or eNOS inhibitors and abolished by a GLP-1 receptor antagonist. Similar effects were obtained by applying GLP-1 (7-36) or GLP-1 (9-36). Co-incubation of exendin-4 and GLP-1 did not show additive effects. Our results suggest that exendin-4 stimulates proliferation of HCAECs through PKA-PI3K/Akt-eNOS activation pathways via a GLP-1 receptor-dependent mechanism.
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Affiliation(s)
- O Erdogdu
- Karolinska Institutet, Department of Clinical Science and Education, Unit for Diabetes Research, Södersjukhuset, Stockholm, Sweden
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97
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Li XD, Yang YJ, Geng YJ, Jin C, Hu FH, Zhao JL, Zhang HT, Cheng YT, Qian HY, Wang LL, Zhang BJ, Wu YL. Tongxinluo reduces myocardial no-reflow and ischemia-reperfusion injury by stimulating the phosphorylation of eNOS via the PKA pathway. Am J Physiol Heart Circ Physiol 2010; 299:H1255-61. [PMID: 20693395 DOI: 10.1152/ajpheart.00459.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of the present study was to investigate whether pretreatment with single low loading dose of tongxinluo (TXL), a traditional Chinese medicine, 1 h before myocardial ischemia could attenuate no-reflow and ischemia-reperfusion injury by regulating endothelial nitric oxide synthase (eNOS) via the PKA pathway. In a 90-min ischemia and 3-h reperfusion model, minipigs were randomly assigned to the following groups: sham, control, TXL (0.05 g/kg, gavaged 1 h before ischemia), TXL + H-89 (a PKA inhibitor, intravenously infused at a dose of 1.0 μg·kg(-1)·min(-1) 30 min before ischemia), and TXL + N(ω)-nitro-L-arginine (L-NNA; an eNOS inhibitor, intravenously administered at a dose of 10 mg/kg 30 min before ischemia). TXL decreased creatine kinase (CK) activity (P < 0.05) and reduced the no-reflow area from 48.6% to 9.5% and infarct size from 78.5% to 59.2% (P < 0.05), whereas these effects of TXL were partially abolished by H-89 and completely reversed by L-NNA. TXL elevated PKA activity and the expression of PKA, Thr(198) phosphorylated PKA, Ser(1179) phosphorylated eNOS, and Ser(635) phosphorylated eNOS in the ischemic myocardium. H-89 repressed the TXL-induced enhancement of PKA activity and phosphorylation of eNOS at Ser(635), and L-NNA counteracted the phosphorylation of eNOS at Ser(1179) and Ser(635) without an apparent influence on PKA activity. In conclusion, pretreatment with a single low loading dose of TXL 1 h before ischemia reduces myocardial no-reflow and ischemia-reperfusion injury by upregulating the phosphorylation of eNOS at Ser(1179) and Ser(635), and this effect is partially mediated by the PKA pathway.
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Affiliation(s)
- Xiang-Dong Li
- Department of Cardiology, Fuwai Hospital and Cardiovascular Institute, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
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98
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Molecular mechanism of endothelial nitric-oxide synthase activation by Platycodon grandiflorum root-derived saponins. Toxicol Lett 2010; 195:106-13. [DOI: 10.1016/j.toxlet.2010.03.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 03/06/2010] [Accepted: 03/08/2010] [Indexed: 11/22/2022]
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99
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Komarova Y, Malik AB. Regulation of endothelial permeability via paracellular and transcellular transport pathways. Annu Rev Physiol 2010; 72:463-93. [PMID: 20148685 DOI: 10.1146/annurev-physiol-021909-135833] [Citation(s) in RCA: 480] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The endothelium functions as a semipermeable barrier regulating tissue fluid homeostasis and transmigration of leukocytes and providing essential nutrients across the vessel wall. Transport of plasma proteins and solutes across the endothelium involves two different routes: one transcellular, via caveolae-mediated vesicular transport, and the other paracellular, through interendothelial junctions. The permeability of the endothelial barrier is an exquisitely regulated process in the resting state and in response to extracellular stimuli and mediators. The focus of this review is to provide a comprehensive overview of molecular and signaling mechanisms regulating endothelial barrier permeability with emphasis on the cross-talk between paracellular and transcellular transport pathways.
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Affiliation(s)
- Yulia Komarova
- Department of Pharmacology and Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, IL 60612, USA
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100
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Fleming I. Molecular mechanisms underlying the activation of eNOS. Pflugers Arch 2010; 459:793-806. [PMID: 20012875 DOI: 10.1007/s00424-009-0767-7] [Citation(s) in RCA: 300] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 11/25/2009] [Accepted: 11/26/2009] [Indexed: 01/08/2023]
Abstract
Endothelial cells situated at the interface between blood and the vessel wall play a crucial role in controlling vascular tone and homeostasis, particularly in determining the expression of pro- and anti-atherosclerotic genes. Many of these effects are mediated by changes in the generation and release of the vasodilator nitric oxide (NO) in response to hemodynamic stimuli exerted on the luminal surface of endothelial cells by the streaming blood (shear stress) and the cyclic strain of the vascular wall. The endothelial NO synthase (eNOS) is activated in response to fluid shear stress and numerous agonists via cellular events such as; increased intracellular Ca(2+), interaction with substrate and co-factors, as well as adaptor and regulatory proteins, protein phosphorylation, and through shuttling between distinct sub-cellular domains. Dysregulation of these processes leads to attenuated eNOS activity and reduced NO output which is a characteristic feature of numerous patho-physiological disorders such as diabetes and atherosclerosis. This review summarizes some of the recent findings relating to the molecular events regulating eNOS activity.
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Affiliation(s)
- Ingrid Fleming
- Institute for Vascular Signalling, Centre for Molecular Medicine, Johann Wolfgang Goethe University, Theodor Stern Kai 7, 60596, Frankfurt am Main, Germany.
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