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The Soluble Guanylyl Cyclase Activator BAY 60-2770 Ameliorates Overactive Bladder in Obese Mice. J Urol 2014; 191:539-47. [DOI: 10.1016/j.juro.2013.09.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2013] [Indexed: 11/20/2022]
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202
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Alexandre EC, Leiria LO, Silva FH, Mendes-Silvério CB, Calmasini FB, Davel APC, Mónica FZ, De Nucci G, Antunes E. Soluble guanylyl cyclase (sGC) degradation and impairment of nitric oxide-mediated responses in urethra from obese mice: reversal by the sGC activator BAY 60-2770. J Pharmacol Exp Ther 2014; 349:2-9. [PMID: 24421320 DOI: 10.1124/jpet.113.211029] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Obesity has emerged as a major contributing risk factor for overactive bladder (OAB), but no study examined urethral smooth muscle (USM) dysfunction as a predisposing factor to obesity-induced OAB. This study investigated the USM relaxant machinery in obese mice and whether soluble guanylyl cyclase (sGC) activation with BAY 60-2770 [acid 4-({(4-carboxybutyl) [2-(5-fluoro-2-{[4-(trifluoromethyl) biphenyl-4-yl] methoxy} phenyl) ethyl] amino} methyl) benzoic] rescues the urethral reactivity through improvement of sGC-cGMP (cyclic guanosine monophosphate) signaling. Male C57BL/6 mice were fed for 12 weeks with a high-fat diet to induce obesity. Separate groups of animals were treated with BAY 60-2770 (1 mg/kg per day for 2 weeks). Functional assays and measurements of cGMP, reactive-oxygen species (ROS), and sGC protein expression in USM were determined. USM relaxations induced by NO (acidified sodium nitrite), NO donors (S-nitrosoglutathione and glyceryl trinitrate), and BAY 41-2272 [5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine] (sGC stimulator) were markedly reduced in obese compared with lean mice. In contrast, USM relaxations induced by BAY 60-2770 (sGC activator) were 43% greater in obese mice (P < 0.05), which was accompanied by increases in cGMP levels. Oxidation of sGC with ODQ [1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one] (10 μM) potentiated BAY 60-2770-induced USM responses in the lean group. Long-term oral BAY 60-2770 administration fully prevented the impairment of USM relaxations in obese mice. Reactive-oxygen species (ROS) production was enhanced, but protein expression of β1 second guanylate cyclase subunit was reduced in USM from obese mice, both of which were restored by BAY 60-2770 treatment. In conclusion, impaired USM relaxation in obese mice is associated with ROS generation and down-regulation of sGC-cGMP signaling. Prevention of sGC degradation by BAY 60-2770 ameliorates the impairment of urethral relaxations in obese mice.
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Affiliation(s)
- Eduardo C Alexandre
- Departments of Pharmacology (E.C.A., L.O.L., F.H.S., C.B.M.S., F.B.C., F.Z.M., G.D.N., E.A.) and Anatomy, Cellular Biology, Physiology, and Biophysics (A.P.C.D.), University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
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Armitage ME, La M, Schmidt HHHW, Wingler K. Diagnosis and individual treatment of cardiovascular diseases: targeting vascular oxidative stress. Expert Rev Clin Pharmacol 2014; 3:639-48. [DOI: 10.1586/ecp.10.40] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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204
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Raat NJ, Tabima DM, Specht PA, Tejero J, Champion HC, Kim-Shapiro DB, Baust J, Mik EG, Hildesheim M, Stasch JP, Becker EM, Truebel H, Gladwin MT. Direct sGC activation bypasses NO scavenging reactions of intravascular free oxy-hemoglobin and limits vasoconstriction. Antioxid Redox Signal 2013; 19:2232-43. [PMID: 23697678 PMCID: PMC3869448 DOI: 10.1089/ars.2013.5181] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 05/10/2013] [Accepted: 05/22/2013] [Indexed: 01/26/2023]
Abstract
AIMS Hemoglobin-based oxygen carriers (HBOC) provide a potential alternative to red blood cell (RBC) transfusion. Their clinical application has been limited by adverse effects, in large part thought to be mediated by the intravascular scavenging of the vasodilator nitric oxide (NO) by cell-free plasma oxy-hemoglobin. Free hemoglobin may also cause endothelial dysfunction and platelet activation in hemolytic diseases and after transfusion of aged stored RBCs. The new soluble guanylate cyclase (sGC) stimulator Bay 41-8543 and sGC activator Bay 60-2770 directly modulate sGC, independent of NO bioavailability, providing a potential therapeutic mechanism to bypass hemoglobin-mediated NO inactivation. RESULTS Infusions of human hemoglobin solutions and the HBOC Oxyglobin into rats produced a severe hypertensive response, even at low plasma heme concentrations approaching 10 μM. These reactions were only observed for ferrous oxy-hemoglobin and not analogs that do not rapidly scavenge NO. Infusions of L-NG-Nitroarginine methyl ester (L-NAME), a competitive NO synthase inhibitor, after hemoglobin infusion did not produce additive vasoconstriction, suggesting that vasoconstriction is related to scavenging of vascular NO. Open-chest hemodynamic studies confirmed that hypertension occurred secondary to direct effects on increasing vascular resistance, with limited negative cardiac inotropic effects. Intravascular hemoglobin reduced the vasodilatory potency of sodium nitroprusside (SNP) and sildenafil, but had no effect on vasodilatation by direct NO-independent activation of sGC by BAY 41-8543 and BAY 60-2770. INNOVATION AND CONCLUSION These data suggest that both sGC stimulators and sGC activators could be used to restore cyclic guanosine monophosphate-dependent vasodilation in conditions where cell-free plasma hemoglobin is sufficient to inhibit endogenous NO signaling.
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Affiliation(s)
- Nicolaas J.H. Raat
- Laboratory of Experimental Anesthesiology, Department of Anesthesiology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - D. Marcela Tabima
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Patricia A.C. Specht
- Laboratory of Experimental Anesthesiology, Department of Anesthesiology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Jesús Tejero
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Hunter C. Champion
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Daniel B. Kim-Shapiro
- Department of Physics and the Translational Science Center, Wake Forest University, Winston-Salem, North Carolina
| | - Jeff Baust
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Egbert G. Mik
- Laboratory of Experimental Anesthesiology, Department of Anesthesiology, Erasmus MC—University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Mariana Hildesheim
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Johannes-Peter Stasch
- Bayer Pharma AG, Wuppertal, Germany
- Institute of Pharmacy, Martin Luther University, Halle, Germany
| | - Eva-Maria Becker
- Bayer Pharma AG, Wuppertal, Germany
- Department of Human Medicine, University Witten/Herdecke, Witten, Germany
| | - Hubert Truebel
- Bayer Pharma AG, Wuppertal, Germany
- Department of Human Medicine, University Witten/Herdecke, Witten, Germany
| | - Mark T. Gladwin
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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Lasker GF, Pankey EA, Kadowitz PJ. Modulation of soluble guanylate cyclase for the treatment of erectile dysfunction. Physiology (Bethesda) 2013; 28:262-9. [PMID: 23817801 DOI: 10.1152/physiol.00001.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Nitric oxide (NO) is the principal mediator of penile erection, and PDE-5 inhibitors are the first-line agents used to treat erectile dysfunction (ED). When NO formation or bioavailability is decreased by oxidative stress and PDE-5 inhibitors are no longer effective, a new class of agents called soluble guanylate cyclase (sGC) stimulators like BAY 41-8543 will induce erection. sGC stimulators bind to the normally reduced, NO-sensitive form of sGC to increase cGMP formation and promote erection. The sGC stimulators produce normal erectile responses when NO formation is inhibited and the nerves innervating the corpora cavernosa are damaged. However, with severe oxidative stress, the heme iron on sGC can be oxidized, rendering the enzyme unresponsive to NO or sGC stimulators. In this pathophysiological situation, another newly developed class of agents called sGC activators can increase the catalytic activity of the oxidized enzyme, increase cGMP formation, and promote erection. The use of newer agents that stimulate or activate sGC to promote erection and treat ED is discussed in this brief review article.
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Affiliation(s)
- George F Lasker
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana, USA
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206
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Glynos C, Dupont LL, Vassilakopoulos T, Papapetropoulos A, Brouckaert P, Giannis A, Joos GF, Bracke KR, Brusselle GG. The role of soluble guanylyl cyclase in chronic obstructive pulmonary disease. Am J Respir Crit Care Med 2013; 188:789-99. [PMID: 23841447 DOI: 10.1164/rccm.201210-1884oc] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
RATIONALE Soluble guanylyl cyclase (sGC), a cyclic guanosine 5'-monophosphate-generating enzyme, regulates smooth muscle tone and exerts antiinflammatory effects in animal models of asthma and acute lung injury. In chronic obstructive pulmonary disease (COPD), primarily caused by cigarette smoke (CS), lung inflammation persists and smooth muscle tone remains elevated, despite ample amounts of nitric oxide that could activate sGC. OBJECTIVES To determine the expression and function of sGC in patients with COPD and in a murine model of COPD. METHODS Expression of sGCα1, α2, and β1 subunits was examined in lungs of never-smokers, smokers without airflow limitation, and patients with COPD; and in C57BL/6 mice after 3 days, 4 weeks, and 24 weeks of CS exposure. The functional role of sGC was investigated in vivo by measuring bronchial responsiveness to serotonin in mice using genetic and pharmacologic approaches. MEASUREMENTS AND MAIN RESULTS Pulmonary expression of sGC, both at mRNA and protein level, was decreased in smokers without airflow limitation and in patients with COPD, and correlated with disease severity (FEV1%). In mice, exposure to CS reduced sGC, cyclic guanosine 5'-monophosphate levels, and protein kinase G activity. sGCα1(-/-) mice exposed to CS exhibited bronchial hyperresponsiveness to serotonin. Activation of sGC by BAY 58-2667 restored the sGC signaling and attenuated bronchial hyperresponsiveness in CS-exposed mice. CONCLUSIONS Down-regulation of sGC because of CS exposure might contribute to airflow limitation in COPD.
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Affiliation(s)
- Constantinos Glynos
- 1 Laboratory for Translational Research in Obstructive Pulmonary Diseases, Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
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Bice JS, Keim Y, Stasch JP, Baxter GF. NO-independent stimulation or activation of soluble guanylyl cyclase during early reperfusion limits infarct size. Cardiovasc Res 2013; 101:220-8. [PMID: 24259501 PMCID: PMC3896250 DOI: 10.1093/cvr/cvt257] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aims Guanylyl cyclase-cyclic guanosine monophosphate signalling plays an important role in endogenous cardioprotective signalling. The aim was to assess the potential of direct pharmacological activation and stimulation of soluble guanylyl cyclase, targeting different redox states of the enzyme, to limit myocardial necrosis during early reperfusion. Methods and results Rat isolated hearts were subjected to reversible left coronary artery occlusion (ischaemia-reperfusion) and infarct size was assessed by the tetrazolium staining technique. Administration during early reperfusion of BAY 41-2272, an NO-independent, haem-dependent stimulator of soluble guanylyl cyclase targeting the reduced state, or BAY 60-2770, an NO-independent, haem-independent activator targeting the oxidized state, significantly limited infarct size. Inhibition of NO synthesis did not abrogate this protection, but exogenous perfusion of NO with BAY 41-2272 produced a synergistic effect. The haem site oxidiser, ODQ abrogated the protection afforded by BAY 41-2272 but potentiated the protection afforded by BAY 60-2770. Targeting both the reduced and oxidized forms of sGC together did not afford additive protection. Conclusions Targeting either reduced or oxidized forms of sGC during early reperfusion affords cardioprotection, providing support for the concept that direct sGC manipulation at reperfusion has therapeutic potential for the management of acute myocardial infarction.
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Affiliation(s)
- Justin S Bice
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, King Edward VII Avenue, Cardiff CF10 3NB, UK
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208
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Gheorghiade M, Marti CN, Sabbah HN, Roessig L, Greene SJ, Böhm M, Burnett JC, Campia U, Cleland JGF, Collins SP, Fonarow GC, Levy PD, Metra M, Pitt B, Ponikowski P, Sato N, Voors AA, Stasch JP, Butler J. Soluble guanylate cyclase: a potential therapeutic target for heart failure. Heart Fail Rev 2013; 18:123-34. [PMID: 22622468 DOI: 10.1007/s10741-012-9323-1] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The number of annual hospitalizations for heart failure (HF) and the mortality rates among patients hospitalized for HF remains unacceptably high. The search continues for safe and effective agents that improve outcomes when added to standard therapy. The nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway serves an important physiologic role in both vascular and non-vascular tissues, including regulation of myocardial and renal function, and is disrupted in the setting of HF, leading to decreased protection against myocardial injury, ventricular remodeling, and the cardio-renal syndrome. The impaired NO-sGC-cGMP pathway signaling in HF is secondary to reduced NO bioavailability and an alteration in the redox state of sGC, making it unresponsive to NO. Accordingly, increasing directly the activity of sGC is an attractive pharmacologic strategy. With the development of two novel classes of drugs, sGC stimulators and sGC activators, the hypothesis that restoration of NO-sGC-cGMP signaling is beneficial in HF patients can now be tested. Characterization of these agents in pre-clinical and clinical studies has begun with investigations suggesting both hemodynamic effects and organ-protective properties independent of hemodynamic changes. The latter could prove valuable in long-term low-dose therapy in HF patients. This review will explain the role of the NO-sGC-cGMP pathway in HF pathophysiology and outcomes, data obtained with sGC stimulators and sGC activators in pre-clinical and clinical studies, and a plan for the further clinical development to study these agents as HF therapy.
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Affiliation(s)
- Mihai Gheorghiade
- Center of Cardiovascular Innovation, Northwestern University Feinberg School of Medicine, 645 North Michigan Ave, Suite 1006, Chicago, IL 60611, USA.
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209
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Hoffmann LS, Kretschmer A, Lawrenz B, Hucke A, Hocher B, Stasch JP. Chronic activation of heme free soluble guanylate cyclase leads to cardio-renal protection in experimental hypertension. BMC Pharmacol Toxicol 2013; 14. [PMCID: PMC3765534 DOI: 10.1186/2050-6511-14-s1-p30] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Linda S Hoffmann
- Pharma Research Centre, Bayer HealthCare, Aprather Weg 18a, Wuppertal, Germany,Martin-Luther-University, School of Pharmacy, Wolfgang-Langenbeck-Str.4,Halle,Germany,Current address, Institute of Pharmacology and Toxicology, University of Bonn, Sigmund-Freud- Strasse 25, 53127 Bonn, Germany
| | - Axel Kretschmer
- Pharma Research Centre, Bayer HealthCare, Aprather Weg 18a, Wuppertal, Germany
| | - Bettina Lawrenz
- Pharma Research Centre, Bayer HealthCare, Aprather Weg 18a, Wuppertal, Germany
| | - Andreas Hucke
- Pharma Research Centre, Bayer HealthCare, Aprather Weg 18a, Wuppertal, Germany
| | - Berthold Hocher
- Center for Cardiovascular Research, Department of Pharmacology and Toxicology, Charité, Campus Mitte, Hessische Str. 3-4, Berlin, Germany
| | - Johannes-Peter Stasch
- Pharma Research Centre, Bayer HealthCare, Aprather Weg 18a, Wuppertal, Germany,Martin-Luther-University, School of Pharmacy, Wolfgang-Langenbeck-Str.4,Halle,Germany
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210
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Vandendriessche B, Rogge E, Goossens V, Vandenabeele P, Stasch JP, Brouckaert P, Cauwels A. The soluble guanylate cyclase activator BAY 58-2667 protects against morbidity and mortality in endotoxic shock by recoupling organ systems. PLoS One 2013; 8:e72155. [PMID: 24015214 PMCID: PMC3756074 DOI: 10.1371/journal.pone.0072155] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 07/05/2013] [Indexed: 01/29/2023] Open
Abstract
Sepsis and septic shock are associated with high mortality rates and the majority of sepsis patients die due to complications of multiple organ failure (MOF). The cyclic GMP (cGMP) producing enzyme soluble guanylate cyclase (sGC) is crucially involved in the regulation of (micro)vascular homeostasis, cardiac function and, consequently, organ function. However, it can become inactivated when exposed to reactive oxygen species (ROS). The resulting heme-free sGC can be reactivated by the heme- and nitric oxide (NO)-independent sGC activator BAY 58-2667 (Cinaciguat). We report that late (+8 h) post-treatment with BAY 58-2667 in a mouse model can protect against lethal endotoxic shock. Protection was associated with reduced hypothermia, circulating IL-6 levels, cardiomyocyte apoptosis, and mortality. In contrast to BAY 58-2667, the sGC stimulator BAY 41-2272 and the phosphodiesterase 5 inhibitor Sildenafil did not have any beneficial effect on survival, emphasizing the importance of the selectivity of BAY 58-2667 for diseased vessels and tissues. Hemodynamic parameters (blood pressure and heart rate) were decreased, and linear and nonlinear indices of blood pressure variability, reflective for (un)coupling of the communication between the autonomic nervous system and the heart, were improved after late protective treatment with BAY 58-2667. In conclusion, our results demonstrate the pivotal role of the NO/sGC axis in endotoxic shock. Stabilization of sGC function with BAY 58-2667 can prevent mortality when given in the correct treatment window, which probably depends on the dynamics of the heme-free sGC pool, in turn influenced by oxidative stress. We speculate that, considering the central role of sGC signaling in many pathways required for maintenance of (micro)circulatory homeostasis, BAY 58-2667 supports organ function by recoupling inter-organ communication pathways.
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Affiliation(s)
- Benjamin Vandendriessche
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Elke Rogge
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Vera Goossens
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Peter Vandenabeele
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | | | - Peter Brouckaert
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Anje Cauwels
- Department for Molecular Biomedical Research, VIB, Ghent, Belgium
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- * E-mail:
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211
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Follmann M, Griebenow N, Hahn MG, Hartung I, Mais FJ, Mittendorf J, Schäfer M, Schirok H, Stasch JP, Stoll F, Straub A. The chemistry and biology of soluble guanylate cyclase stimulators and activators. Angew Chem Int Ed Engl 2013; 52:9442-62. [PMID: 23963798 DOI: 10.1002/anie.201302588] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Indexed: 12/14/2022]
Abstract
The vasodilatory properties of nitric oxide (NO) have been utilized in pharmacotherapy for more than 130 years. Still today, NO-donor drugs are important in the management of cardiovascular diseases. However, inhaled NO or drugs releasing NO and organic nitrates are associated with noteworthy therapeutic shortcomings, including resistance to NO in some disease states, the development of tolerance during long-term treatment, and nonspecific effects, such as post-translational modification of proteins. The beneficial actions of NO are mediated by stimulation of soluble guanylate cyclase (sGC), a heme-containing enzyme which produces the intracellular signaling molecule cyclic guanosine monophosphate (cGMP). Recently, two classes of compounds have been discovered that amplify the function of sGC in a NO-independent manner, the so-called sGC stimulators and sGC activators. The most advanced drug, the sGC stimulator riociguat, has successfully undergone Phase III clinical trials for different forms of pulmonary hypertension.
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Affiliation(s)
- Markus Follmann
- Bayer Pharma Aktiengesellschaft, Global Drug Discovery, Aprather Weg 18a, 42113 Wuppertal, Germany.
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Follmann M, Griebenow N, Hahn MG, Hartung I, Mais FJ, Mittendorf J, Schäfer M, Schirok H, Stasch JP, Stoll F, Straub A. Chemie und Biologie der Stimulatoren und Aktivatoren der löslichen Guanylatcyclase. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302588] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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213
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Abstract
Heart failure is an important public health problem that is increasing in prevalence throughout the world. Not only is this condition common, but it is associated with significant morbidity and mortality as well as high costs to medical care systems. Vasodilator drugs help unload the heart and may have other effects that could benefit heart failure patients. Consequently, they have emerged as an important therapeutic approach for patients with this condition. Novel vasodilator therapies that are currently in development target new pathways, potentially giving clinicians alternate options for improving outcomes in this vulnerable population. This review focuses on investigational drugs that have the ability to dilate blood vessels amongst their therapeutic properties. These drugs include the natriuretic peptides that activate particulate guanylate cyclase, the novel agent cinaciguat that activates the soluble guanylate cyclase system, and finally a recombinant form of the naturally occurring vasodilating agent relaxin, a hormone that mediates many of the changes that allows the cardiovascular system to successfully adapt to pregnancy.
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214
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Thoonen R, Sips PY, Bloch KD, Buys ES. Pathophysiology of hypertension in the absence of nitric oxide/cyclic GMP signaling. Curr Hypertens Rep 2013; 15:47-58. [PMID: 23233080 DOI: 10.1007/s11906-012-0320-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signaling system is a well-characterized modulator of cardiovascular function, in general, and blood pressure, in particular. The availability of mice mutant for key enzymes in the NO-cGMP signaling system facilitated the identification of interactions with other blood pressure modifying pathways (e.g. the renin-angiotensin-aldosterone system) and of gender-specific effects of impaired NO-cGMP signaling. In addition, recent genome-wide association studies identified blood pressure-modifying genetic variants in genes that modulate NO and cGMP levels. Together, these findings have advanced our understanding of how NO-cGMP signaling regulates blood pressure. In this review, we will summarize the results obtained in mice with disrupted NO-cGMP signaling and highlight the relevance of this pathway as a potential therapeutic target for the treatment of hypertension.
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Affiliation(s)
- Robrecht Thoonen
- Molecular Cardiology Research Institute, Molecular Cardiology Research Center, Tufts Medical Center, Boston, MA 02111, USA.
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215
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Sips PY, Buys ES. Genetic modification of hypertension by sGCα1. Trends Cardiovasc Med 2013; 23:312-8. [PMID: 23755896 DOI: 10.1016/j.tcm.2013.05.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 04/30/2013] [Accepted: 05/01/2013] [Indexed: 02/06/2023]
Abstract
Hypertension is an important modifiable risk factor for coronary heart disease, congestive heart failure, stroke, end-stage renal disease, and peripheral vascular disease, but many of the molecular mechanisms and genetic factors underlying the development of the most common forms of human hypertension remain to be defined. Abundant evidence suggests that nitric oxide (NO) and one of its primary targets, the cyclic guanosine monophosphate (cGMP)-generating enzyme soluble guanylate cyclase (sGC), have a critical role in regulating blood pressure. The availability of murine models of hypertension and the revolution in human genetics research (e.g., genome-wide association studies [GWAS]), resulting in the identification of dozens of genetic loci that affect normal variation in blood pressure and susceptibility to hypertension, provide a unique opportunity to dissect the mechanisms by which NO-cGMP signaling regulates blood pressure and to gain important insights into the pathogenesis of hypertension. In this review, we will give an overview of the current knowledge relating to the role of sGC in the regulation of blood pressure, discussing data obtained from genetically modified mouse models as well as from human genetic studies.
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Affiliation(s)
- Patrick Y Sips
- Anesthesia Center for Critical Care Research, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Thier 511B, Boston, MA 02114
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Mohan S, Patel H, Bolinaga J, Soekamto N. AMP-activated protein kinase regulates L-arginine mediated cellular responses. Nutr Metab (Lond) 2013; 10:40. [PMID: 23718875 PMCID: PMC3680329 DOI: 10.1186/1743-7075-10-40] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/25/2013] [Indexed: 12/31/2022] Open
Abstract
Background Our prior study revealed the loss in short-term L-Arginine (ARG) therapeutic efficacy after continuous exposure; resulting in tolerance development, mediated by endothelial nitric oxide synthase (eNOS) down-regulation, secondary to oxidative stress and induced glucose accumulation. However, the potential factor regulating ARG cellular response is presently unknown. Method Human umbilical vein endothelial cells were incubated with 100 μM ARG for 2 h in buffer (short-term or acute), or for 7 days in culture medium and challenged for 2 h in buffer (continuous or chronic), in the presence or absence of other agents. eNOS activity was determined by analyzing cellular nitrite/nitrate (NO2–/NO3–), and AMP-activated protein kinase (AMPK) activity was assayed using SAMS peptide. 13C6 glucose was added to medium to measure glucose uptake during cellular treatments, which were determined by LC-MS/MS. Cellular glucose was identified by o-toluidine method. Superoxide (O2•–) was identified by EPR-spin-trap, and peroxynitrite (ONOO–) was measured by flow-cytometer using aminophenyl fluorescein dye. Results Short-term incubation of cells with 100 μM ARG in the presence or absence of 30 μM L-NG-Nitroarginine methyl ester (L-NAME) or 30 μM AMPK inhibitor (compound C, CMP-C) increased cellular oxidative stress and overall glucose accumulation with no variation in glucose transporter-1 (GLUT-1), or AMPK activity from control. The increase in total NO2–/NO3– after 2 h 100 μM ARG exposure, was suppressed in cells co-incubated with 30 μM CMP-C or L-NAME. Long-term exposure of ARG with or without CMP-C or L-NAME suppressed NO2–/NO3–, glucose uptake, GLUT-1, AMPK expression and activity below control, and increased overall cellular glucose, O2•– and ONOO–. Gluconeogenesis inhibition with 30 μM 5-Chloro-2-N-2,5-dichlorobenzenesulfonamido-benzoxazole (CDB) during ARG exposure for 2 h maintained overall cellular glucose to control, but increased cellular glucose uptake. Continuous co-incubation with CDB and ARG increased NO2–/NO3–, glucose uptake, GLUT-1, AMPK expression and activity, and maintained overall cellular glucose, O2•– and ONOO– to control conditions. Conclusion The present study provides the fundamental evidence for AMPK as the primary modulator of ARG cellular responses and for regulating the mode of glucose accumulation during short-term and continuous ARG treatments.
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Affiliation(s)
- Srinidi Mohan
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New England, 716 Stevens Avenue, Portland, ME 04103, USA
| | - Harsh Patel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New England, 716 Stevens Avenue, Portland, ME 04103, USA
| | - Jorge Bolinaga
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New England, 716 Stevens Avenue, Portland, ME 04103, USA
| | - Nathania Soekamto
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New England, 716 Stevens Avenue, Portland, ME 04103, USA
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Kumar V, Martin F, Hahn MG, Schaefer M, Stamler JS, Stasch JP, van den Akker F. Insights into BAY 60-2770 activation and S-nitrosylation-dependent desensitization of soluble guanylyl cyclase via crystal structures of homologous nostoc H-NOX domain complexes. Biochemistry 2013; 52:3601-8. [PMID: 23614626 DOI: 10.1021/bi301657w] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The soluble guanylyl cyclase (sGC) is an important receptor for nitric oxide (NO). Nitric oxide activates sGC several hundred fold to generate cGMP from GTP. Because of sGC's salutary roles in cardiovascular physiology, it has received substantial attention as a drug target. The heme domain of sGC is key to its regulation as it not only contains the NO activation site but also harbors sites for NO-independent sGC activators as well an S-nitrosylation site (β1 C122) involved in desensitization. Here we report the crystal structure of the activator BAY 60-2770 bound to the Nostoc H-NOX domain that is homologous to sGC. The structure reveals that BAY 60-2770 has displaced the heme and acts as a heme mimetic via carboxylate-mediated interactions with the conserved YxSxR motif as well as hydrophobic interactions. Comparisons with the previously determined BAY 58-2667 bound structure reveal that BAY 60-2770 is more ordered in its hydrophobic tail region. sGC activity assays demonstrate that BAY 60-2770 has about 10% higher fold maximal stimulation compared to BAY 58-2667. S-Nitrosylation of the BAY 60-2770 substituted Nostoc H-NOX domain causes subtle changes in the vicinity of the S-nitrosylated C122 residue. These shifts could impact the adjacent YxSxR motif and αF helix and as such potentially inhibit either heme incorporation or NO-activation of sGC and thus provide a structural basis for desensitization.
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Affiliation(s)
- Vijay Kumar
- Department of Biochemistry, Case Western Reserve University , Cleveland, Ohio 44106, United States
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COSYNS SMR, DHAESE I, THOONEN R, BUYS ES, VRAL A, BROUCKAERT P, LEFEBVRE RA. Heme deficiency of soluble guanylate cyclase induces gastroparesis. Neurogastroenterol Motil 2013; 25:e339-52. [PMID: 23551931 PMCID: PMC4932850 DOI: 10.1111/nmo.12120] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 02/27/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND Soluble guanylate cyclase (sGC) is the principal target of nitric oxide (NO) to control gastrointestinal motility. The consequence on nitrergic signaling and gut motility of inducing a heme-free status of sGC, as induced by oxidative stress, was investigated. METHODS sGCβ1 (H105F) knock-in (apo-sGC) mice, which express heme-free sGC that has basal activity, but cannot be stimulated by NO, were generated. KEY RESULTS Diethylenetriamine NONOate did not increase sGC activity in gastrointestinal tissue of apo-sGC mice. Exogenous NO did not induce relaxation in fundic, jejunal and colonic strips, and pyloric rings of apo-sGC mice. The stomach was enlarged in apo-sGC mice with hypertrophy of the muscularis externa of the fundus and pylorus. In addition, gastric emptying and intestinal transit were delayed and whole-gut transit time was increased in the apo-sGC mice, while distal colonic transit time was maintained. The nitrergic relaxant responses to electrical field stimulation at 1-4 Hz were abolished in fundic and jejunal strips from apo-sGC mice, but in pyloric rings and colonic strips, only the response at 1 Hz was abolished, indicating the contribution of other transmitters than NO. CONCLUSIONS & INFERENCES The results indicate that the gastrointestinal consequences of switching from a native sGC to a heme-free sGC, which cannot be stimulated by NO, are most pronounced at the level of the stomach establishing a pivotal role of the activation of sGC by NO in normal gastric functioning. In addition, delayed intestinal transit was observed, indicating that nitrergic activation of sGC also plays a role in the lower gastrointestinal tract.
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Affiliation(s)
- S. M. R. COSYNS
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
| | - I. DHAESE
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
| | - R. THOONEN
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium,Tufts Medical Center, Molecular Cardiology Research Center, Boston, MA, USA
| | - E. S. BUYS
- Anesthesia Center for Critical Care Research, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - A. VRAL
- Department of Medical Basic Sciences, Ghent University, Ghent, Belgium
| | - P. BROUCKAERT
- Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - R. A. LEFEBVRE
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
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Lasker GF, Pankey EA, Allain AV, Murthy SN, Stasch JP, Kadowitz PJ. The selective Rho-kinase inhibitor azaindole-1 has long-lasting erectile activity in the rat. Urology 2013; 81:465.e7-14. [PMID: 23374844 DOI: 10.1016/j.urology.2012.10.039] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/11/2012] [Accepted: 10/24/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To investigate the effects of the selective Rho-associated protein kinase (ROCK) inhibitor azaindole-1 on erectile function under physiologic and pathophysiologic conditions in the rat. METHODS The effect of intracavernosal (i.c.) injections of azaindole-1 on change in intracavernous pressure (ICP), ICP/mean arterial pressure (MAP), area under the curve (AUC), and response duration were investigated in the anesthetized rat under control conditions and when nonadrenergic noncholinergic neurotransmission and cholinergic function or soluble guanylyl cyclase (sGC) were inhibited or after cavernosal nerve crush injury. RESULTS The i.c. injections of azaindole-1 produced dose-related increases in ICP/MAP and AUC that were long-lasting at the highest doses studied compared with the prototypical ROCK inhibitor fasudil. Erectile responses were not altered by 7-nitroindazole and atropine in doses that reduced the response to cavernosal nerve stimulation by 86%, indicating that they were independent of NO release by cavernosal nerves or activation of muscarinic receptors in the corpora cavernosa. Erectile responses to azaindole-1 were not altered by the sGC inhibitor ODQ in a dose that attenuated responses to the NO donor sodium nitroprusside, indicating that they were independent of an action on sGC. The erectile response to i.c. injections of azaindole-1 or Y-27632, which was reported to be NO/cyclic guanosine monophosphate-dependent, was not attenuated after cavernosal nerve crush injury. CONCLUSION The present studies indicate that azaindole-1 has long-lasting erectile activity that is independent of NO release, muscarinic receptor, or sGC activation or the integrity of the cavernosal nerves.
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Affiliation(s)
- George F Lasker
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, Louisiana 70112-2699, USA
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Lasker GF, Pankey EA, Frink TJ, Zeitzer JR, Walter KA, Kadowitz PJ. The sGC activator BAY 60-2770 has potent erectile activity in the rat. Am J Physiol Heart Circ Physiol 2013; 304:H1670-9. [PMID: 23585129 DOI: 10.1152/ajpheart.00062.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitric oxide (NO) is the principal mediator of penile erection, and soluble guanylate cyclase (sGC) is the receptor for NO. In pathophysiological conditions when sGC is inactivated and not responsive to NO or sGC stimulators a new class of agents called sGC activators increase the activity of NO-insensitive sGC and produce erection. The aim of this study was to investigate erectile responses to BAY 60-2770, a sGC activator, under physiological and pathophysiological conditions. In the present study increases in intracavernosal pressure (ICP) in response to intracavernosal (ic) injections of BAY 60-2770 were investigated under baseline conditions, when sGC was inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), when nitric oxide synthase (NOS) was inhibited by N-nitro-L-arginine methyl ester (L-NAME), and after cavernosal nerve crush injury. Under baseline conditions ic injections of BAY 60-2770 increase ICP, ICP/mean arterial pressure (MAP), and area under the ICP curve (AUC) and produce small decreases in MAP at the highest doses studied. BAY 60-2770 was very potent in its ability to induce erection and responses to BAY 60-2770 were enhanced by ODQ which attenuates erectile responses to sodium nitroprusside (SNP), diethylamine NONOate (DEA/NO), and cavernosal nerve stimulation. Responses to BAY 60-2770 were not altered by L-NAME or cavernosal nerve crush injury. These data indicate that BAY 60-2770 has potent erectile activity that is enhanced by ODQ and show that responses to BAY 60-2770 are not attenuated by NOS inhibition or cavernosal nerve injury. These results suggest that BAY 60-2770 would be effective in the treatment of erectile dysfunction when NO bioavailability is reduced, after pelvic nerve injury, and when sGC is oxidized.
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Affiliation(s)
- George F Lasker
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA 70112, USA
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Kagota S, Maruyama K, Tada Y, Fukushima K, Umetani K, Wakuda H, Shinozuka K. Chronic oxidative-nitrosative stress impairs coronary vasodilation in metabolic syndrome model rats. Microvasc Res 2013; 88:70-8. [PMID: 23571030 DOI: 10.1016/j.mvr.2013.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 03/02/2013] [Accepted: 04/01/2013] [Indexed: 01/22/2023]
Abstract
Metabolic syndrome (MetS) is a combination of clinical disorders that together increase the risk for cardiovascular disease and diabetes. SHRSP.Z-Lepr(fa)/IzmDmcr (SHRSP.ZF) rats with MetS show impaired nitric oxide-mediated relaxation in coronary and mesenteric arteries, and angiotensin II receptor type 1 blockers protect against dysfunction and oxidative-nitrosative stress independently of metabolic effects. We hypothesize that superoxide contributes to functional deterioration in SHRSP.ZF rats. To test our hypothesis, we studied effects of treatment with tempol, a membrane-permeable radical scavenger, on impaired vasodilation in SHRSP.ZF rats. Tempol did not alter body weight, high blood pressure, or metabolic abnormalities, but prevented impairment of acetylcholine-induced and nitroprusside-induced vasodilation in the coronary and mesenteric arteries. Furthermore, tempol reduced the levels of serum thiobarbituric acid reactive substance (TBARS) and 3-nitrotyrosine content in mesenteric arteries. Systemic administration of tempol elevated the expression of soluble guanylate cyclase (sGC) above basal levels in mesenteric arteries of SHRSP.ZF rats. However, acute treatment with tempol or ebselen, a peroxynitrite scavenger, did not ameliorate impaired relaxation of isolated mesenteric arteries. No nitration of tyrosine residues in sGC was observed; however, sGC mRNA expression levels in the arteries of SHRSP.ZF rats were lower than those in the arteries of Wistar-Kyoto rats. Levels of Thr(496)- and Ser(1177)-phosphorylated endothelial nitric oxide synthase (eNOS) were lower in arteries of SHRSP.ZF rats, and acetylcholine decreased Thr(496)-phosphorylated eNOS levels. These results indicated that prolonged superoxide production, leading to oxidative-nitrosative stress, was associated with impaired vasodilation in SHRSP.ZF rats with MetS. Down-regulated sGC expression may be linked to dysfunction, while reduced NO bioavailability/eNOS activity and modified sGC activity due to superoxide production were excluded as pivotal mechanisms.
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Affiliation(s)
- Satomi Kagota
- Department of Pharmacology, School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya, Japan.
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Soluble guanylate cyclase α1-deficient mice: a novel murine model for primary open angle glaucoma. PLoS One 2013; 8:e60156. [PMID: 23527308 PMCID: PMC3603933 DOI: 10.1371/journal.pone.0060156] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Accepted: 02/21/2013] [Indexed: 12/29/2022] Open
Abstract
Primary open angle glaucoma (POAG) is a leading cause of blindness worldwide. The molecular signaling involved in the pathogenesis of POAG remains unknown. Here, we report that mice lacking the α1 subunit of the nitric oxide receptor soluble guanylate cyclase represent a novel and translatable animal model of POAG, characterized by thinning of the retinal nerve fiber layer and loss of optic nerve axons in the context of an open iridocorneal angle. The optic neuropathy associated with soluble guanylate cyclase α1-deficiency was accompanied by modestly increased intraocular pressure and retinal vascular dysfunction. Moreover, data from a candidate gene association study suggests that a variant in the locus containing the genes encoding for the α1 and β1 subunits of soluble guanylate cyclase is associated with POAG in patients presenting with initial paracentral vision loss, a disease subtype thought to be associated with vascular dysregulation. These findings provide new insights into the pathogenesis and genetics of POAG and suggest new therapeutic strategies for POAG.
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223
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Miller JD, Chu Y, Castaneda LE, Serrano KM, Brooks RM, Heistad DD. Vascular function during prolonged progression and regression of atherosclerosis in mice. Arterioscler Thromb Vasc Biol 2013; 33:459-65. [PMID: 23307875 PMCID: PMC3960951 DOI: 10.1161/atvbaha.112.252700] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Endothelial dysfunction is associated with atherosclerosis in mice, but it is difficult to reduce cholesterol levels enough to study regression of atherosclerosis in genetically modified mice. The goal of this study was to examine vascular structure and function before and after reducing elevated plasma lipid levels with a genetic switch in Reversa mice, and identify novel mechanisms contributing to structural and functional improvements in the vasculature after reduction of blood lipids. METHODS AND RESULTS After 6 months of hypercholesterolemia, endothelial function (maximum relaxation to acetylcholine) in aorta was impaired and responses to nitric oxide were unaffected. Further impairment in endothelial function was observed after 12 months of hypercholesterolemia and was associated with reductions in sensitivity to nitric oxide. Expression of dihydrofolate reductase was reduced at 6 and 12 months, and addition of the tetrahydrobiopterin precursor sepiapterin significantly improved endothelial function. Reducing cholesterol levels at 6 months normalized dihydrofolate reductase expression and prevented further impairment in endothelial function. Similar functional changes were observed after 12 months of hypercholesterolemia followed by 2 months of lipid lowering. CONCLUSIONS Our data suggest that endothelial dysfunction after prolonged hypercholesterolemia is the result of both impairment of sensitivity to nitric oxide and reduced nitric oxide synthase cofactor bioavailability. Both of these changes can be prevented by normalizing blood lipids during moderately severe or advanced atherosclerosis.
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Affiliation(s)
- Jordan D. Miller
- Departments of Internal Medicine, University of Iowa Carver College of Medicine
| | | | - Lauren E. Castaneda
- Departments of Internal Medicine, University of Iowa Carver College of Medicine
| | - Kristine M. Serrano
- Departments of Internal Medicine, University of Iowa Carver College of Medicine
| | - Robert M. Brooks
- Departments of Internal Medicine, University of Iowa Carver College of Medicine
| | - Donald D. Heistad
- Departments of Internal Medicine, University of Iowa Carver College of Medicine
- Departments of Pharmacology, University of Iowa Carver College of Medicine
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Shah MR, Wedgwood S, Czech L, Kim GA, Lakshminrusimha S, Schumacker PT, Steinhorn RH, Farrow KN. Cyclic stretch induces inducible nitric oxide synthase and soluble guanylate cyclase in pulmonary artery smooth muscle cells. Int J Mol Sci 2013; 14:4334-48. [PMID: 23429274 PMCID: PMC3588102 DOI: 10.3390/ijms14024334] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 02/12/2013] [Accepted: 02/17/2013] [Indexed: 12/29/2022] Open
Abstract
In the pulmonary vasculature, mechanical forces such as cyclic stretch induce changes in vascular signaling, tone and remodeling. Nitric oxide is a potent regulator of soluble guanylate cyclase (sGC), which drives cGMP production, causing vasorelaxation. Pulmonary artery smooth muscle cells (PASMCs) express inducible nitric oxide synthase (iNOS), and while iNOS expression increases during late gestation, little is known about how cyclic stretch impacts this pathway. In this study, PASMC were subjected to cyclic stretch of 20% amplitude and frequency of 1 Hz for 24 h and compared to control cells maintained under static conditions. Cyclic stretch significantly increased cytosolic oxidative stress as compared to static cells (62.9 ± 5.9% vs. 33.3 ± 5.7% maximal oxidation), as measured by the intracellular redox sensor roGFP. Cyclic stretch also increased sGCβ protein expression (2.5 ± 0.9-fold), sGC activity (1.5 ± 0.2-fold) and cGMP levels (1.8 ± 0.2-fold), as well as iNOS mRNA and protein expression (3.0 ± 0.9 and 2.6 ± 0.7-fold, respectively) relative to control cells. An antioxidant, recombinant human superoxide dismutase (rhSOD), significantly decreased stretch-induced cytosolic oxidative stress, but did not block stretch-induced sGC activity. Inhibition of iNOS with 1400 W or an iNOS-specific siRNA inhibited stretch-induced sGC activity by 30% and 68% respectively vs. static controls. In conclusion, cyclic stretch increases sGC expression and activity in an iNOS-dependent manner in PASMC from fetal lambs. The mechanism that produces iNOS and sGC upregulation is not yet known, but we speculate these effects represent an early compensatory mechanism to counteract the effects of stretch-induced oxidative stress. A better understanding of the interplay between these two distinct pathways could provide key insights into future avenues to treat infants with pulmonary hypertension.
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Affiliation(s)
- Monica R. Shah
- Department of Pediatrics, Northwestern University, Chicago, IL 60611, USA; E-Mails: (M.R.S.); (L.C.); (G.A.K.); (P.T.S.)
| | - Stephen Wedgwood
- Department of Pediatrics, University of California, Davis, CA 95817, USA; E-Mails: (S.W.); (R.H.S.)
| | - Lyubov Czech
- Department of Pediatrics, Northwestern University, Chicago, IL 60611, USA; E-Mails: (M.R.S.); (L.C.); (G.A.K.); (P.T.S.)
| | - Gina A. Kim
- Department of Pediatrics, Northwestern University, Chicago, IL 60611, USA; E-Mails: (M.R.S.); (L.C.); (G.A.K.); (P.T.S.)
| | - Satyan Lakshminrusimha
- Department of Pediatrics and Physiology, University of Buffalo, Buffalo, NY 14222, USA; E-Mail:
| | - Paul T. Schumacker
- Department of Pediatrics, Northwestern University, Chicago, IL 60611, USA; E-Mails: (M.R.S.); (L.C.); (G.A.K.); (P.T.S.)
| | - Robin H. Steinhorn
- Department of Pediatrics, University of California, Davis, CA 95817, USA; E-Mails: (S.W.); (R.H.S.)
| | - Kathryn N. Farrow
- Department of Pediatrics, Northwestern University, Chicago, IL 60611, USA; E-Mails: (M.R.S.); (L.C.); (G.A.K.); (P.T.S.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-312-503-3435; Fax: +1-312-503-1181
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Thunemann M, Fomin N, Krawutschke C, Russwurm M, Feil R. Visualization of cGMP with cGi biosensors. Methods Mol Biol 2013; 1020:89-120. [PMID: 23709028 DOI: 10.1007/978-1-62703-459-3_6] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Cyclic guanosine 3'-5'-monophosphate (cGMP) is an important signaling molecule in physiology, pathophysiology, and pharmacological therapy. It has been proposed that the functional outcome of an increase of cGMP in a given cell largely depends on the existence of global versus local cGMP pools. The recent development of genetically encoded fluorescent biosensors for cGMP is a major technical advance in order to monitor the spatiotemporal dynamics and compartmentalization of cGMP signals in living cells. Here we give an overview of the available cGMP sensors and how they can be used to visualize cGMP. The focus is on the fluorescence resonance energy transfer (FRET)-based cGi-type sensors (Russwurm et al., Biochem J 407:69-77, 2007), which are currently among the most useful tools for cGMP imaging in cells, tissues, and living organisms. We present detailed protocols that cover the entire imaging experiment, from the isolation of primary cells from cGi-transgenic mice and adenoviral expression of cGi sensors to the description of the setup required to record FRET changes in single cells and tissues. In-cell calibration of sensors and data evaluation is also described in detail and the limitations and common pitfalls of cGMP imaging are discussed. Specifically, we outline the use of FRET microscopy to visualize cGMP in murine smooth muscle cells (from aorta, bladder, and colon) and cerebellar granule neurons expressing cGi sensors. Most of the protocols can be easily adapted to other cell types and cGMP indicators and can be used as general guidelines for cGMP imaging in living cells, tissues and, eventually, whole organisms.
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Affiliation(s)
- Martin Thunemann
- Interfakultäres Institut für Biochemie, Universität Tübingen, Tübingen, Germany
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226
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Schmidt PM, Stasch JP. Receptor binding assay for NO-independent activators of soluble guanylate cyclase. Methods Mol Biol 2013; 1020:205-214. [PMID: 23709035 DOI: 10.1007/978-1-62703-459-3_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The characterization of the interaction between a ligand and its receptor is crucial for a broad variety of applications in academia as well as in the pharmaceutical industry. Although various sophisticated high-throughput technologies have been established to investigate the binding of ligands to their receptors, classical filtration-based receptor binding assays still have some advantages when smaller number of samples need to be tested. Here we describe a technically easy, cheap, and reliable receptor binding assay that was successfully applied to determine the binding constant of the NO-independent activator of soluble guanylate cyclase, cinaciguat, and the impact of other small molecules on its interaction with the enzyme.
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227
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Alisaraie L, Fu Y, Tuszynski JA. Dynamic change of heme environment in soluble guanylate cyclase and complexation of NO-independent drug agents with H-NOX domain. Chem Biol Drug Des 2012; 81:359-81. [PMID: 23095288 DOI: 10.1111/cbdd.12082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Soluble guanylate cyclase is a heterodimer receptor that functions in several signal transduction pathways. Conversion of guanosine 5'-triphosphate to 3',5'-cyclic monophosphate second messenger at the catalytic domain is regulated by the changes at heme nitric oxide/oxygen domain of the β-subunit. To better understand conformational changes at heme site that may impact on activities of catalytic domain, three soluble guanylate cyclase homolog proteins with heme at Fe-His state were investigated, and their dynamic behaviors were monitored in both unliganded (apo) and complex with heme. As a result of dynamic conformational changes, Lys110, Asp45, Arg135, and Glu41 were found interacting with the site gate, which may interfere with transportation of small molecules in and out of the heme site. An alternative binding site adjacent to that of heme was identified. Binding affinity of several nitric oxide-independent activators and heme-dependent stimulators was examined, and their binding modes in the heme site and in the alternative binding site in the human soluble guanylate cyclase enzyme were computationally simulated. The calculated binding energies were used as criteria to filter results of virtual high-throughput screenings based on FlexX ligand-docking algorithm and absorption, distribution, metabolism, excretion, and toxicity properties on databases of available drugs. The identified drugs from virtual high-throughput screening have been suggested for experimental investigations, based on which they may either be directly repurposed or require structural modifications for better physico-chemical and pharmacological properties.
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Affiliation(s)
- Laleh Alisaraie
- Department of Oncology, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada.
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Mendes-Silverio CB, Leiria LOS, Morganti RP, Anhê GF, Marcondes S, Mónica FZ, De Nucci G, Antunes E. Activation of haem-oxidized soluble guanylyl cyclase with BAY 60-2770 in human platelets lead to overstimulation of the cyclic GMP signaling pathway. PLoS One 2012; 7:e47223. [PMID: 23144808 PMCID: PMC3493568 DOI: 10.1371/journal.pone.0047223] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 09/12/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND AIMS Nitric oxide-independent soluble guanylyl cyclase (sGC) activators reactivate the haem-oxidized enzyme in vascular diseases. This study was undertaken to investigate the anti-platelet mechanisms of the haem-independent sGC activator BAY 60-2770 in human washed platelets. The hypothesis that sGC oxidation potentiates the anti-platelet activities of BAY 60-2770 has been tested. METHODS Human washed platelet aggregation and adhesion assays, as well as flow cytometry for α(IIb)β(3) integrin activation and Western blot for α1 and β1 sGC subunits were performed. Intracellular calcium levels were monitored in platelets loaded with a fluorogenic calcium-binding dye (FluoForte). RESULTS BAY 60-2770 (0.001-10 µM) produced significant inhibition of collagen (2 µg/ml)- and thrombin (0.1 U/ml)-induced platelet aggregation that was markedly potentiated by the sGC inhibitor ODQ (10 µM). In fibrinogen-coated plates, BAY 60-2770 significantly inhibited platelet adhesion, an effect potentiated by ODQ. BAY 60-2770 increased the cGMP levels and reduced the intracellular Ca(2+) levels, both of which were potentiated by ODQ. The cell-permeable cGMP analogue 8-Br-cGMP (100 µM) inhibited platelet aggregation and Ca(2+) levels in an ODQ-insensitive manner. The cAMP levels remained unchanged by BAY 60-2770. Collagen- and thrombin-induced α(IIb)β(3) activation was markedly inhibited by BAY 60-2770 that was further inhibited by ODQ. The effects of sodium nitroprusside (3 µM) were all prevented by ODQ. Incubation with ODQ (10 µM) significantly reduced the protein levels of α1 and β1 sGC subunits, which were prevented by BAY 60-2770. CONCLUSION The inhibitory effects of BAY 60-2770 on aggregation, adhesion, intracellular Ca(2+) levels and α(IIb)β(3) activation are all potentiated in haem-oxidizing conditions. BAY 60-2770 prevents ODQ-induced decrease in sGC protein levels. BAY 60-2770 could be of therapeutic interest in cardiovascular diseases associated with thrombotic complications.
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Affiliation(s)
- Camila B. Mendes-Silverio
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Luiz O. S. Leiria
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Rafael P. Morganti
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Gabriel F. Anhê
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Sisi Marcondes
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Fabíola Z. Mónica
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Gilberto De Nucci
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), São Paulo, Brazil
- * E-mail:
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229
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Irvine JC, Ganthavee V, Love JE, Alexander AE, Horowitz JD, Stasch JP, Kemp-Harper BK, Ritchie RH. The soluble guanylyl cyclase activator bay 58-2667 selectively limits cardiomyocyte hypertrophy. PLoS One 2012; 7:e44481. [PMID: 23144773 PMCID: PMC3492396 DOI: 10.1371/journal.pone.0044481] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/07/2012] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Although evidence now suggests cGMP is a negative regulator of cardiac hypertrophy, the direct consequences of the soluble guanylyl cyclase (sGC) activator BAY 58-2667 on cardiac remodeling, independent of changes in hemodynamic load, has not been investigated. In the present study, we tested the hypothesis that the NO(•)-independent sGC activator BAY 58-2667 inhibits cardiomyocyte hypertrophy in vitro. Concomitant impact of BAY 58-2667 on cardiac fibroblast proliferation, and insights into potential mechanisms of action, were also sought. Results were compared to the sGC stimulator BAY 41-2272. METHODS Neonatal rat cardiomyocytes were incubated with endothelin-1 (ET(1), 60nmol/L) in the presence and absence of BAY 41-2272 and BAY 58-2667 (0.01-0.3 µmol/L). Hypertrophic responses and its triggers, as well as cGMP signaling, were determined. The impact of both sGC ligands on basal and stimulated cardiac fibroblast proliferation in vitro was also determined. RESULTS We now demonstrate that BAY 58-2667 (0.01-0.3 µmol/L) elicited concentration-dependent antihypertrophic actions, inhibiting ET(1)-mediated increases in cardiomyocyte 2D area and de novo protein synthesis, as well as suppressing ET(1)-induced cardiomyocyte superoxide generation. This was accompanied by potent increases in cardiomyocyte cGMP accumulation and activity of its downstream signal, vasodilator-stimulated phosphoprotein (VASP), without elevating cardiomyocyte cAMP. In contrast, submicromolar concentrations of BAY 58-2667 had no effect on basal or stimulated cardiac fibroblast proliferation. Indeed, only at concentrations ≥10 µmol/L was inhibition of cardiac fibrosis seen in vitro. The effects of BAY 58-2667 in both cell types were mimicked by BAY 41-2272. CONCLUSIONS Our results demonstrate that BAY 58-2667 elicits protective, cardiomyocyte-selective effects in vitro. These actions are associated with sGC activation and are evident in the absence of confounding hemodynamic factors, at low (submicromolar) concentrations. Thus this distinctive sGC ligand may potentially represent an alternative therapeutic approach for limiting myocardial hypertrophy.
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Affiliation(s)
- Jennifer C. Irvine
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Virat Ganthavee
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Jane E. Love
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Amy E. Alexander
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - John D. Horowitz
- Cardiology Unit, The Queen Elizabeth Hospital, Woodville South, South Australia, Australia
| | | | | | - Rebecca H. Ritchie
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Medicine, Monash University, Clayton, Victoria, Australia
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Abstract
The present review first summarizes the complex chain of events, in endothelial and vascular smooth muscle cells, that leads to endothelium-dependent relaxations (vasodilatations) due to the generation of nitric oxide (NO) by endothelial nitric oxide synthase (eNOS) and how therapeutic interventions may improve the bioavailability of NO and thus prevent/cure endothelial dysfunction. Then, the role of other endothelium-derived mediators (endothelium-derived hyperpolarizing (EDHF) and contracting (EDCF) factors, endothelin-1) and signals (myoendothelial coupling) is summarized also, with special emphasis on their interaction(s) with the NO pathway, which make the latter not only a major mediator but also a key regulator of endothelium-dependent responses.
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231
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Fernhoff NB, Derbyshire ER, Underbakke ES, Marletta MA. Heme-assisted S-nitrosation desensitizes ferric soluble guanylate cyclase to nitric oxide. J Biol Chem 2012; 287:43053-62. [PMID: 23093402 DOI: 10.1074/jbc.m112.393892] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nitric oxide (NO) signaling regulates key processes in cardiovascular physiology, specifically vasodilation, platelet aggregation, and leukocyte rolling. Soluble guanylate cyclase (sGC), the mammalian NO sensor, transduces an NO signal into the classical second messenger cyclic GMP (cGMP). NO binds to the ferrous (Fe(2+)) oxidation state of the sGC heme cofactor and stimulates formation of cGMP several hundred-fold. Oxidation of the sGC heme to the ferric (Fe(3+)) state desensitizes the enzyme to NO. The heme-oxidized state of sGC has emerged as a potential therapeutic target in the treatment of cardiovascular disease. Here, we investigate the molecular mechanism of NO desensitization and find that sGC undergoes a reductive nitrosylation reaction that is coupled to the S-nitrosation of sGC cysteines. We further characterize the kinetics of NO desensitization and find that heme-assisted nitrosothiol formation of β1Cys-78 and β1Cys-122 causes the NO desensitization of ferric sGC. Finally, we provide evidence that the mechanism of reductive nitrosylation is gated by a conformational change of the protein. These results yield insights into the function and dysfunction of sGC in cardiovascular disease.
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Affiliation(s)
- Nathaniel B Fernhoff
- Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA
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232
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Müller PM, Gnügge R, Dhayade S, Thunemann M, Krippeit-Drews P, Drews G, Feil R. H₂O₂ lowers the cytosolic Ca²⁺ concentration via activation of cGMP-dependent protein kinase Iα. Free Radic Biol Med 2012; 53:1574-83. [PMID: 22922339 DOI: 10.1016/j.freeradbiomed.2012.08.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 08/06/2012] [Accepted: 08/07/2012] [Indexed: 11/21/2022]
Abstract
The cGMP-dependent protein kinase I (cGKI) is a key mediator of cGMP signaling, but the specific functions of its two isoforms, cGKIα and cGKIβ, are poorly understood. Recent studies indicated a novel cGMP-independent role for cGKIα in redox sensing. To dissect the effects of oxidative stress on the cGKI isoforms, we used mouse embryonic fibroblasts and vascular smooth muscle cells (VSMCs) expressing both, one, or none of them. In cGKIα-expressing cells, but not in cells expressing only cGKIβ, incubation with H₂O₂ induced the formation of a disulfide bond between the two identical subunits of the dimeric enzyme. Oxidation of cGKIα was associated with increased phosphorylation of its substrate, vasodilator-stimulated phosphoprotein. H₂O₂ did not stimulate cGMP production, indicating that it activates cGKIα directly via oxidation. Interestingly, there was a mutual influence of H₂O₂ and cGMP on cGKI activity and disulfide bond formation, respectively; preoxidation of the kinase with H₂O₂ slightly impaired its activation by cGMP, whereas preactivation of the enzyme with cGMP attenuated its oxidation by H₂O₂. To evaluate the functional relevance of the noncanonical H₂O₂-cGKIα pathway, we studied the regulation of the cytosolic Ca²⁺ concentration ([Ca²⁺](i)). H₂O₂ suppressed norepinephrine-induced Ca²⁺ transients in cGKIα-expressing VSMCs and, to a lower extent, in VSMCs expressing only cGKIβ or none of the isoforms. Thus, H₂O₂ lowers [Ca²⁺](i) mainly via a cGKIα-dependent pathway. These results indicate that oxidative stress selectively targets the cGKIα isoform, which then modulates cellular processes in a cGMP-independent manner. A decrease in [Ca²⁺](i) in VSMCs via activation of cGKIα might be a major mechanism of H₂O₂-induced vasodilation.
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MESH Headings
- Animals
- Blotting, Western
- Calcium/metabolism
- Cells, Cultured
- Cyclic GMP/metabolism
- Cyclic GMP-Dependent Protein Kinase Type I/metabolism
- Cytosol/metabolism
- Disulfides/metabolism
- Embryo, Mammalian/cytology
- Embryo, Mammalian/drug effects
- Embryo, Mammalian/enzymology
- Female
- Fibroblasts/cytology
- Fibroblasts/drug effects
- Fibroblasts/enzymology
- Hydrogen Peroxide/pharmacology
- Mice
- Mice, Inbred C57BL
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Oxidants/pharmacology
- Signal Transduction
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Affiliation(s)
- Paul Markus Müller
- Interfakultäres Institut für Biochemie, University of Tübingen, 72076 Tübingen, Germany
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233
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Schmidt K, Neubauer A, Kolesnik B, Stasch JP, Werner ER, Gorren ACF, Mayer B. Tetrahydrobiopterin protects soluble guanylate cyclase against oxidative inactivation. Mol Pharmacol 2012; 82:420-7. [PMID: 22648973 DOI: 10.1124/mol.112.079855] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Tetrahydrobiopterin (BH4) is a major endogenous vasoprotective agent that improves endothelial function by increasing nitric oxide (NO) synthesis and scavenging of superoxide and peroxynitrite. Therefore, administration of BH4 is considered a promising therapy for cardiovascular diseases associated with endothelial dysfunction and oxidative stress. Here we report on a novel function of BH4 that might contribute to the beneficial vascular effects of the pteridine. Treatment of cultured porcine aortic endothelial cells with nitroglycerin (GTN) or 1H-[1,2,4]-oxadiazolo[4,3-a]quinoxaline-1-one (ODQ) resulted in heme oxidation of soluble guanylate cyclase (sGC), as evident from diminished NO-induced cGMP accumulation that was paralleled by increased cGMP response to a heme- and NO-independent activator of soluble guanylate cyclase [4-([(4-carboxybutyl)[2-(5-fluoro-2-([4'-(trifluoromethyl)biphenyl-4-yl]methoxy)phenyl)ethyl]amino]methyl)benzoic acid (BAY 60-2770)]. Whereas scavenging of superoxide and/or peroxynitrite with superoxide dismutase, tiron, Mn(III)tetrakis(4-benzoic acid)porphyrin, and urate had no protective effects, supplementation of the cells with BH4, either by application of BH4 directly or of its precursors dihydrobiopterin or sepiapterin, completely prevented the inhibition of NO-induced cGMP accumulation by GTN and ODQ. Tetrahydroneopterin had the same effect, and virtually identical results were obtained with RFL-6 fibroblasts, suggesting that our observation reflects a general feature of tetrahydropteridines that is unrelated to NO synthase function and not limited to endothelial cells. Protection of sGC against oxidative inactivation may contribute to the known beneficial effects of BH4 in cardiovascular disorders associated with oxidative stress.
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Affiliation(s)
- Kurt Schmidt
- Department of Pharmacology and Toxicology, Karl-Franzens-Universität Graz, Graz, Austria.
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234
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Korkmaz S, Loganathan S, Mikles B, Radovits T, Barnucz E, Hirschberg K, Li S, Hegedüs P, Páli S, Weymann A, Karck M, Szabó G. Nitric oxide- and heme-independent activation of soluble guanylate cyclase attenuates peroxynitrite-induced endothelial dysfunction in rat aorta. J Cardiovasc Pharmacol Ther 2012; 18:70-7. [PMID: 22914857 DOI: 10.1177/1074248412455696] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Oxidative stress interferes with nitric oxide (NO)/soluble guanylate cyclase (sGC)/cyclic guanosine monophosphate (cGMP) signalling pathway through reduction of endogenous NO and formation of the strong intermediate oxidant peroxynitrite and leads to vascular dysfunction. We evaluated the effects of oral treatment with NO- and heme-independent sGC activator cinaciguat on peroxynitrite-induced vascular dysfunction in rat aorta. Sprague-Dawley rats were treated orally 2 times at an interval of 17 hours with vehicle or with cinaciguat (10 mg/kg). One hour after the last treatment, the animals were anesthetized, the thoracic aorta was removed, and the aortic segment preparations were incubated with and without the reactive oxidant peroxynitrite (200 µmol/L, 30 minutes). Endothelium-dependent (acetylcholine), -independent (sodium nitroprusside) vasorelaxations were investigated, and histopathological examination was performed. Incubation of aortic rings with peroxynitrite significantly attenuated the maximal endothelium-dependent relaxation (R (max)) to acetylcholine (peroxynitrite, 44.5% ± 5.9% vs control, 93.2% ± 2.0%, P < .05) and decreased pD(2) values (-logEC(50), EC(50) being the concentration of acetylcholine that elicited 50% of the maximal response) for the concentration-response curves as compared to control segments. Treatment of rats with cinaciguat significantly improved the decreased acetylcholine-induced vasorelaxation after exposure of aortic rings to peroxynitrite (cinaciguat + peroxynitrite, 67.1% ± 3.5% vs peroxynitrite, 44.5% ± 5.9%, P < .05). Incubation of aortic segments with peroxynitrite caused a significant shift of the sodium nitroprusside concentration-response curves to the right without any alterations in the R (max). Moreover, exposure of aortic rings to peroxynitrite resulted in increased nitro-oxidative stress and DNA breakage which were improved by cinaciguat. Treatment of rats with cinaciguat significantly increased intracellular cGMP levels in the aortic wall. Our results show under conditions of nitro-oxidative stress when signalling in the NO/sGC/cGMP pathway is impaired, acute activation of sGC by cinaciguat might be advantageous in the treatment of endothelial dysfunction in cardiovascular disease.
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Affiliation(s)
- Sevil Korkmaz
- Department of Cardiac Surgery, Laboratory of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany.
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235
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Lang M, Kojonazarov B, Tian X, Kalymbetov A, Weissmann N, Grimminger F, Kretschmer A, Stasch JP, Seeger W, Ghofrani HA, Schermuly RT. The soluble guanylate cyclase stimulator riociguat ameliorates pulmonary hypertension induced by hypoxia and SU5416 in rats. PLoS One 2012; 7:e43433. [PMID: 22912874 PMCID: PMC3422306 DOI: 10.1371/journal.pone.0043433] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Accepted: 07/23/2012] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND The nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) signal-transduction pathway is impaired in many cardiovascular diseases, including pulmonary arterial hypertension (PAH). Riociguat (BAY 63-2521) is a stimulator of sGC that works both in synergy with and independently of NO to increase levels of cGMP. The aims of this study were to investigate the role of NO-sGC-cGMP signaling in a model of severe PAH and to evaluate the effects of sGC stimulation by riociguat and PDE5 inhibition by sildenafil on pulmonary hemodynamics and vascular remodeling in severe experimental PAH. METHODS AND RESULTS Severe angioproliferative PAH was induced in rats by combined exposure to the vascular endothelial growth factor receptor antagonist SU5416 and hypoxia (SUHx). Twenty-one days thereafter rats were randomized to receive either riociguat (10 mg/kg/day), sildenafil (50 mg/kg/day) or vehicle by oral gavage, for 14 days until the day of the terminal hemodynamic measurements. Administration of riociguat or sildenafil significantly decreased right ventricular systolic pressure (RVSP). Riociguat significantly decreased RV hypertrophy (RVH) (0.55 ± 0.02, p<0.05), increased cardiac output (60.8 ± .8 mL/minute, p<0.05) and decreased total pulmonary resistance (4.03 ± 0.3 mmHg min(-1) ml(-1) 100 g BW, p<0.05), compared with sildenafil and vehicle. Both compounds significantly decreased the RV collagen content and improved RV function, but the effects of riociguat on tricuspid annular plane systolic excursion and RV myocardial performance were significantly better than those of sildenafil (p<0.05). The proportion of occluded arteries was significantly lower in animals receiving riociguat than in those receiving vehicle (p<0.05); furthermore, the neointima/media ratio was significantly lower in those receiving riociguat than in those receiving sildenafil or vehicle (p<0.05). CONCLUSION Riociguat and sildenafil significantly reduced RVSP and RVH, and improved RV function compared with vehicle. Riociguat had a greater effect on hemodynamics and RVH than sildenafil.
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Affiliation(s)
- Michaela Lang
- University of Giessen and Marburg Lung Center, Giessen, Germany
| | | | - Xia Tian
- University of Giessen and Marburg Lung Center, Giessen, Germany
| | | | | | | | | | | | - Werner Seeger
- University of Giessen and Marburg Lung Center, Giessen, Germany
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | | | - Ralph Theo Schermuly
- University of Giessen and Marburg Lung Center, Giessen, Germany
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
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236
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Cote GJ, Zhu W, Thomas A, Martin E, Murad F, Sharina IG. Hydrogen peroxide alters splicing of soluble guanylyl cyclase and selectively modulates expression of splicing regulators in human cancer cells. PLoS One 2012; 7:e41099. [PMID: 22911749 PMCID: PMC3401163 DOI: 10.1371/journal.pone.0041099] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 06/21/2012] [Indexed: 12/14/2022] Open
Abstract
Background Soluble guanylyl cyclase (sGC) plays a central role in nitric oxide (NO)-mediated signal transduction in the cardiovascular, nervous and gastrointestinal systems. Alternative RNA splicing has emerged as a potential mechanism to modulate sGC expression and activity. C-α1 sGC is an alternative splice form that is resistant to oxidation-induced protein degradation and demonstrates preferential subcellular distribution to the oxidized environment of endoplasmic reticulum (ER). Methodology/Principal Findings Here we report that splicing of C-α1 sGC can be modulated by H2O2 treatment in BE2 neuroblastoma and MDA-MD-468 adenocarcinoma human cells. In addition, we show that the H2O2 treatment of MDA-MD-468 cells selectively decreases protein levels of PTBP1 and hnRNP A2/B1 splice factors identified as potential α1 gene splicing regulators by in silico analysis. We further demonstrate that down-regulation of PTBP1 by H2O2 occurs at the protein level with variable regulation observed in different breast cancer cells. Conclusions/Significance Our data demonstrate that H2O2 regulates RNA splicing to induce expression of the oxidation-resistant C-α1 sGC subunit. We also report that H2O2 treatment selectively alters the expression of key splicing regulators. This process might play an important role in regulation of cellular adaptation to conditions of oxidative stress.
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Affiliation(s)
- Gilbert J. Cote
- Department of Endocrine Neoplasia and Hormonal Disorders, MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Wen Zhu
- Department of Endocrine Neoplasia and Hormonal Disorders, MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Anthony Thomas
- Department of Internal Medicine/Cardiology, University of Texas Medical School, UTHealth, Houston, Texas, United States of America
| | - Emil Martin
- Department of Internal Medicine/Cardiology, University of Texas Medical School, UTHealth, Houston, Texas, United States of America
| | - Ferid Murad
- Department of Biochemistry and Molecular Biology, George Washington University, Washington, DC, United States of America
| | - Iraida G. Sharina
- Department of Internal Medicine/Cardiology, University of Texas Medical School, UTHealth, Houston, Texas, United States of America
- * E-mail:
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237
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Costell MH, Ancellin N, Bernard RE, Zhao S, Upson JJ, Morgan LA, Maniscalco K, Olzinski AR, Ballard VLT, Herry K, Grondin P, Dodic N, Mirguet O, Bouillot A, Gellibert F, Coatney RW, Lepore JJ, Jucker BM, Jolivette LJ, Willette RN, Schnackenberg CG, Behm DJ. Comparison of soluble guanylate cyclase stimulators and activators in models of cardiovascular disease associated with oxidative stress. Front Pharmacol 2012; 3:128. [PMID: 22783192 PMCID: PMC3389674 DOI: 10.3389/fphar.2012.00128] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 06/18/2012] [Indexed: 12/20/2022] Open
Abstract
Soluble guanylate cyclase (sGC), the primary mediator of nitric oxide (NO) bioactivity, exists as reduced (NO-sensitive) and oxidized (NO-insensitive) forms. We tested the hypothesis that the cardiovascular protective effects of NO-insensitive sGC activation would be potentiated under conditions of oxidative stress compared to those of NO-sensitive sGC stimulation. The cardiovascular effects of the NO-insensitive sGC activator GSK2181236A [a low, non-depressor dose, and a high dose which lowered mean arterial pressure (MAP) by 5-10 mmHg] and those of equi-efficacious doses of the NO-sensitive sGC stimulator BAY 60-4552 were assessed in (1) Sprague Dawley rats during coronary artery ischemia/reperfusion (I/R) and (2) spontaneously hypertensive stroke prone rats (SHR-SP) on a high salt/fat diet (HSFD). In I/R, neither compound reduced infarct size 24 h after reperfusion. In SHR-SP, HSFD increased MAP, urine output, microalbuminuria, and mortality, caused left ventricular hypertrophy with preserved ejection fraction, and impaired endothelium-dependent vasorelaxation. The low dose of BAY 60-4552, but not that of GSK2181236A, decreased urine output, and improved survival. Conversely, the low dose of GSK2181236A, but not that of BAY 60-4552, attenuated the development of cardiac hypertrophy. The high doses of both compounds similarly attenuated cardiac hypertrophy and improved survival. In addition to these effects, the high dose of BAY 60-4552 reduced urine output and microalbuminuria and attenuated the increase in MAP to a greater extent than did GSK2181236A. Neither compound improved endothelium-dependent vasorelaxation. In SHR-SP isolated aorta, the vasodilatory responses to the NO-dependent compounds carbachol and sodium nitroprusside were attenuated by HSFD. In contrast, the vasodilatory responses to both GSK2181236A and BAY 60-4552 were unaltered by HSFD, indicating that reduced NO-bioavailability and not changes in the oxidative state of sGC is responsible for the vascular dysfunction. In summary, GSK2181236A and BAY 60-4552 provide partial benefit against hypertension-induced end-organ damage. The differential beneficial effects observed between these compounds could reflect tissue-specific changes in the oxidative state of sGC and might help direct the clinical development of these novel classes of therapeutic agents.
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Affiliation(s)
- Melissa H. Costell
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Nicolas Ancellin
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Roberta E. Bernard
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Shufang Zhao
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - John J. Upson
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Lisa A. Morgan
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Kristeen Maniscalco
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Alan R. Olzinski
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Victoria L. T. Ballard
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Kenny Herry
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Pascal Grondin
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Nerina Dodic
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Olivier Mirguet
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Anne Bouillot
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Francoise Gellibert
- Lipid Metabolism Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area UnitGlaxoSmithKline, Les Ulis, France
| | - Robert W. Coatney
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - John J. Lepore
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Beat M. Jucker
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Larry J. Jolivette
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Robert N. Willette
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - Christine G. Schnackenberg
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
| | - David J. Behm
- Heart Failure Discovery Performance Unit, Metabolic Pathways and Cardiovascular Therapy Area Unit, GlaxoSmithKlineKing of Prussia, PA, USA
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Crassous PA, Couloubaly S, Huang C, Zhou Z, Baskaran P, Kim DD, Papapetropoulos A, Fioramonti X, Durán WN, Beuve A. Soluble guanylyl cyclase is a target of angiotensin II-induced nitrosative stress in a hypertensive rat model. Am J Physiol Heart Circ Physiol 2012; 303:H597-604. [PMID: 22730391 DOI: 10.1152/ajpheart.00138.2012] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nitric oxide (NO) by activating soluble guanylyl cyclase (sGC) is involved in vascular homeostasis via induction of smooth muscle relaxation. In cardiovascular diseases (CVDs), endothelial dysfunction with altered vascular reactivity is mostly attributed to decreased NO bioavailability via oxidative stress. However, in several studies, relaxation to NO is only partially restored by exogenous NO donors, suggesting sGC impairment. Conflicting results have been reported regarding the nature of this impairment, ranging from decreased expression of one or both subunits of sGC to heme oxidation. We showed that sGC activity is impaired by thiol S-nitrosation. Recently, angiotensin II (ANG II) chronic treatment, which induces hypertension, was shown to generate nitrosative stress in addition to oxidative stress. We hypothesized that S-nitrosation of sGC occurs in ANG II-induced hypertension, thereby leading to desensitization of sGC to NO hence vascular dysfunction. As expected, ANG II infusion increases blood pressure, aorta remodeling, and protein S-nitrosation. Intravital microscopy indicated that cremaster arterioles are resistant to NO-induced vasodilation in vivo in anesthetized ANG II-treated rats. Concomitantly, NO-induced cGMP production decreases, which correlated with S-nitrosation of sGC in hypertensive rats. This study suggests that S-nitrosation of sGC by ANG II contributes to vascular dysfunction. This was confirmed in vitro by using A7r5 smooth muscle cells infected with adenoviruses expressing sGC or cysteine mutants: ANG II decreases NO-stimulated activity in the wild-type but not in one mutant, C516A. This result indicates that cysteine 516 of sGC mediates ANG II-induced desensitization to NO in cells.
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Affiliation(s)
- Pierre-Antoine Crassous
- Department of Pharmacology and Physiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
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239
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Buys ES, Raher MJ, Kirby A, Shahid M, Mohd S, Baron DM, Hayton SR, Tainsh LT, Sips PY, Rauwerdink KM, Yan Q, Tainsh RET, Shakartzi HR, Stevens C, Decaluwé K, Rodrigues-Machado MDG, Malhotra R, Van de Voorde J, Wang T, Brouckaert P, Daly MJ, Bloch KD. Genetic modifiers of hypertension in soluble guanylate cyclase α1-deficient mice. J Clin Invest 2012; 122:2316-25. [PMID: 22565307 DOI: 10.1172/jci60119] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 03/21/2012] [Indexed: 01/09/2023] Open
Abstract
Nitric oxide (NO) plays an essential role in regulating hypertension and blood flow by inducing relaxation of vascular smooth muscle. Male mice deficient in a NO receptor component, the α1 subunit of soluble guanylate cyclase (sGCα1), are prone to hypertension in some, but not all, mouse strains, suggesting that additional genetic factors contribute to the onset of hypertension. Using linkage analyses, we discovered a quantitative trait locus (QTL) on chromosome 1 that was linked to mean arterial pressure (MAP) in the context of sGCα1 deficiency. This region is syntenic with previously identified blood pressure-related QTLs in the human and rat genome and contains the genes coding for renin. Hypertension was associated with increased activity of the renin-angiotensin-aldosterone system (RAAS). Further, we found that RAAS inhibition normalized MAP and improved endothelium-dependent vasorelaxation in sGCα1-deficient mice. These data identify the RAAS as a blood pressure-modifying mechanism in a setting of impaired NO/cGMP signaling.
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Affiliation(s)
- Emmanuel S Buys
- Anesthesia Center for Critical Care Research, Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
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240
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Surmeli NB, Marletta MA. Insight into the rescue of oxidized soluble guanylate cyclase by the activator cinaciguat. Chembiochem 2012; 13:977-81. [PMID: 22474005 DOI: 10.1002/cbic.201100809] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Indexed: 11/11/2022]
Abstract
Nitric oxide (NO) signaling mediates many important physiological processes through the receptor soluble guanylate cyclase (sGC). Under disease conditions sGC heme can be oxidized resulting in NO insensitivity. Here, we show that the therapeutic compound cinaciguat (Cin) rescues dysfunctional sGC by direct displacement of the oxidized heme.
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241
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Nossaman BD, Pankey EA, Badejo AR, Casey DB, Uppu S, Murthy SN, Kadowitz PJ. Analysis of responses to glyceryl trinitrate and sodium nitrite in the intact chest rat. Nitric Oxide 2012; 26:223-8. [PMID: 22465477 DOI: 10.1016/j.niox.2012.03.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 02/17/2012] [Accepted: 03/22/2012] [Indexed: 10/28/2022]
Abstract
Responses to glyceryl trinitrate/nitroglycerin (GTN), S-nitrosoglutathione (GSNO), and sodium nitrite were compared in the intact chest rat. The iv injections of GTN, sodium nitrite, and GSNO produced dose-dependent decreases in pulmonary and systemic arterial pressures. In as much as cardiac output was not reduced, the decreases in pulmonary and systemic arterial pressures indicate that GTN, sodium nitrite, and GSNO have significant vasodilator activity in the pulmonary and systemic vascular beds in the rat. Responses to GTN were attenuated by cyanamide, but not allopurinol, whereas responses to nitrite formed by the metabolism of GTN were attenuated by allopurinol and cyanamide. The results with allopurinol and cyanamide suggest that only mitochondrial aldehyde dehydrogenase is involved in the bioactivation of GTN, sodium nitrite, and GSNO, whereas both pathways are involved in the bioactivation of nitrite anion in the intact rat. The comparison of vasodilator activity indicates that GSNO and GTN are more than 1000-fold more potent than sodium nitrite in decreasing pulmonary and systemic arterial pressures in the rat. Following administration of 1H-[1,2,4]-oxadizaolo[4,3-]quinoxaline-1-one (ODQ), responses to GTN were significantly attenuated, indicating that responses are mediated by the activation of soluble guanylyl cyclase. These data suggest that the reduction of nitrite to nitric oxide formed from the metabolism of GTN, cannot account for the vasodilator activity of GTN in the intact rat and that another mechanism; perhaps the formation of an S-NO, may mediate the vasodilator response to GTN in this species.
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Affiliation(s)
- Bobby D Nossaman
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
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242
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Casey DB, Pankey EA, Badejo AM, Bueno FR, Bhartiya M, Murthy SN, Uppu RM, Nossaman BD, Kadowitz PJ. Peroxynitrite has potent pulmonary vasodilator activity in the rat. Can J Physiol Pharmacol 2012; 90:485-500. [PMID: 22452357 DOI: 10.1139/y2012-012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Peroxynitrite (PN) worsens pathological conditions associated with oxidative stress. However, beneficial effects have also been reported. PN has been shown to demonstrate vasodilator as well as vasoconstrictor properties that are dependent upon the experimental conditions and the vascular bed studied. PN-induced vascular smooth muscle relaxation may involve the formation of nitric oxide (NO) donors. The present results show that PN has significant vasodilator activity in the pulmonary and systemic vascular beds, and that responses to PN were not attenuated by L-penicillamine (L-PEN), a PN scavenger, whereas responses to sodium nitroprusside (SNP) were decreased. PN had a small inhibitory effect on decreases in arterial pressure in response to the NO donors diethylammonium (Z)-1-(N,N-diethylamino)diazen-1-ium-1,2-diolate (DEA/NO) and S-nitrosoglutathione (GSNO). PN partially reversed hypoxic pulmonary vasoconstriction. PN responses were attenuated by the soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and responses to PN and the PN precursor, 3-morpholinosydnonimine (SIN-1), were different. These data show that PN has potent pulmonary vasodilator activity in the rat, and provide evidence that a PN interaction with S-nitrosothiols is not the major mechanism mediating the response. These data suggest that responses to PN are mediated by the activation of sGC, and that PN has a small inhibitory effect on NO responses.
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Affiliation(s)
- David B Casey
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA 70112-2699, USA
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243
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Novel therapies in acute and chronic heart failure. Pharmacol Ther 2012; 135:1-17. [PMID: 22475446 DOI: 10.1016/j.pharmthera.2012.03.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 03/07/2012] [Indexed: 01/10/2023]
Abstract
Despite past advances in the pharmacological management of heart failure, the prognosis of these patients remains poor, and for many, treatment options remain unsatisfactory. Additionally, the treatments and clinical outcomes of patients with acute decompensated heart failure have not changed substantially over the past few decades. Consequently, there is a critical need for new drugs that can improve clinical outcomes. In the setting of acute heart failure, new inotrops such as cardiac myosin activators and new vasodilators such as relaxin have been developed. For chronic heart failure with reduced ejection fraction, there are several new approaches that target multiple pathophysiological mechanism including novel blockers of the renin-angiotensin-aldosterone system (direct renin inhibitors, dual-acting inhibitors of the angiotensin II receptor and neprilysin, aldosterone synthase inhibitors), ryanodine receptor stabilizers, and SERCA activators. Heart failure with preserved ejection fraction represents a substantial therapeutic problem as no therapy has been demonstrated to improve symptoms or outcomes in this condition. Newer treatment strategies target specific structural and functional abnormalities that lead to increased myocardial stiffness. Dicarbonyl-breaking compounds reverse advanced glycation-induced cross-linking of collagen and improve the compliance of aged and/or diabetic myocardium. Modulation of titin-dependent passive tension can be achieved via phosphorylation of a unique sequence on the extensible region of the protein. This review describes the pathophysiological basis, mechanism of action, and available clinical efficacy data of drugs that are currently under development. Finally, new therapies for the treatment of heart failure complications, such as pulmonary hypertension and anemia, are discussed.
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244
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Wingler K, Hermans JJR, Schiffers P, Moens A, Paul M, Schmidt HHHW. NOX1, 2, 4, 5: counting out oxidative stress. Br J Pharmacol 2012; 164:866-83. [PMID: 21323893 PMCID: PMC3195911 DOI: 10.1111/j.1476-5381.2011.01249.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
For decades, oxidative stress has been discussed as a key mechanism of endothelial dysfunction and cardiovascular disease. However, attempts to validate and exploit this hypothesis clinically by supplementing antioxidants have failed. Nevertheless, this does not disprove the oxidative stress hypothesis. As a certain degree of reactive oxygen species (ROS) formation appears to be physiological and beneficial. To reduce oxidative stress therapeutically, two alternative approaches are being developed. One is the repair of key signalling components that are compromised by oxidative stress. These include uncoupled endothelial nitric oxide (NO) synthase and oxidized/heme-free NO receptor soluble guanylate cyclase. A second approach is to identify and effectively inhibit the relevant source(s) of ROS in a given disease condition. A highly likely target in this context is the family of NADPH oxidases. Animal models, including NOX knockout mice and new pharmacological inhibitors of NADPH oxidases have opened up a new era of oxidative stress research and have paved the way for new cardiovascular therapies.
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Affiliation(s)
- K Wingler
- Department of Pharmacology & Cardiovascular Research Institute Maastricht, Maastricht University, the Netherlands
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245
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Stimulators and activators of soluble guanylate cyclase: review and potential therapeutic indications. Crit Care Res Pract 2012; 2012:290805. [PMID: 22482042 PMCID: PMC3299283 DOI: 10.1155/2012/290805] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2011] [Revised: 11/18/2011] [Accepted: 11/19/2011] [Indexed: 12/15/2022] Open
Abstract
The heme-protein soluble guanylyl cyclase (sGC) is the intracellular receptor for nitric oxide (NO). sGC is a heterodimeric enzyme with α and β subunits and contains a heme moiety essential for binding of NO and activation of the enzyme. Stimulation of sGC mediates physiologic responses including smooth muscle relaxation, inhibition of inflammation, and thrombosis. In pathophysiologic states, NO formation and bioavailability can be impaired by oxidative stress and that tolerance to NO donors develops with continuous use. Two classes of compounds have been developed that can directly activate sGC and increase cGMP formation in pathophysiologic conditions when NO formation and bioavailability are impaired or when NO tolerance has developed. In this report, we review current information on the pharmacology of heme-dependent stimulators and heme-independent activators of sGC in animal and in early clinical studies and the potential role these compounds may have in the management of cardiovascular disease.
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246
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Salloum FN, Das A, Samidurai A, Hoke NN, Chau VQ, Ockaili RA, Stasch JP, Kukreja RC. Cinaciguat, a novel activator of soluble guanylate cyclase, protects against ischemia/reperfusion injury: role of hydrogen sulfide. Am J Physiol Heart Circ Physiol 2012; 302:H1347-54. [PMID: 22268103 DOI: 10.1152/ajpheart.00544.2011] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Cinaciguat (BAY 58-2667) is a novel nitric oxide (NO)-independent activator of soluble guanylate cyclase (sGC), which induces cGMP-generation and vasodilation in diseased vessels. We tested the hypothesis that cinaciguat might trigger protection against ischemia/reperfusion (I/R) in the heart and adult cardiomyocytes through cGMP/protein kinase G (PKG)-dependent generation of hydrogen sulfide (H(2)S). Adult New Zealand White rabbits were pretreated with 1 or 10 μg/kg cinaciguat (iv) or 10% DMSO (vehicle) 15 min before I/R or with 10 μg/kg cinaciguat (iv) at reperfusion. Additionally, adult male ICR mice were treated with either cinaciguat (10 μg/kg ip) or vehicle 30 min before I/R or at the onset of reperfusion (10 μg/kg iv). The PKG inhibitor KT5283 (KT; 1 mg/kg ip) or dl-propargylglycine (PAG; 50 mg/kg ip) the inhibitor of the H(2)S-producing enzyme cystathionine-γ-lyase (CSE) were given 10 and 30 min before cinaciguat. Cardiac function and infarct size were assessed by echocardiography and tetrazolium staining, respectively. Primary adult mouse cardiomyocytes were isolated and treated with cinaciguat before simulated ischemia/reoxygenation. Cinaciguat caused 63 and 41% reduction of infarct size when given before I/R and at reperfusion in rabbits, respectively. In mice, cinaciguat pretreatment caused a more robust 80% reduction in infarct size vs. 63% reduction when given at reperfusion and preserved cardiac function following I/R, which were blocked by KT and PAG. Cinaciguat also caused an increase in myocardial PKG activity and CSE expression. In cardiomyocytes, cinaciguat (50 nM) reduced necrosis and apoptosis and increased H(2)S levels, which was abrogated by KT. Cinaciguat is a novel molecule to induce H(2)S generation and a powerful protection against I/R injury in heart.
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Affiliation(s)
- Fadi N Salloum
- Pauley Heart Center, Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University Medical Center, Richmond, USA
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247
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Tsai EJ, Liu Y, Koitabashi N, Bedja D, Danner T, Jasmin JF, Lisanti MP, Friebe A, Takimoto E, Kass DA. Pressure-overload-induced subcellular relocalization/oxidation of soluble guanylyl cyclase in the heart modulates enzyme stimulation. Circ Res 2012; 110:295-303. [PMID: 22095726 PMCID: PMC4264382 DOI: 10.1161/circresaha.111.259242] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 11/08/2011] [Indexed: 01/17/2023]
Abstract
RATIONALE Soluble guanylyl cyclase (sGC) generates cyclic guanosine monophophate (cGMP) upon activation by nitric oxide (NO). Cardiac NO-sGC-cGMP signaling blunts cardiac stress responses, including pressure-overload-induced hypertrophy. The latter itself depresses signaling through this pathway by reducing NO generation and enhancing cGMP hydrolysis. OBJECTIVE We tested the hypothesis that the sGC response to NO also declines with pressure-overload stress and assessed the role of heme-oxidation and altered intracellular compartmentation of sGC as potential mechanisms. METHODS AND RESULTS C57BL/6 mice subjected to transverse aortic constriction (TAC) developed cardiac hypertrophy and dysfunction. NO-stimulated sGC activity was markedly depressed, whereas NO- and heme-independent sGC activation by BAY 60-2770 was preserved. Total sGCα(1) and β(1) expression were unchanged by TAC; however, sGCβ(1) subunits shifted out of caveolin-enriched microdomains. NO-stimulated sGC activity was 2- to 3-fold greater in Cav3-containing lipid raft versus nonlipid raft domains in control and 6-fold greater after TAC. In contrast, BAY 60-2770 responses were >10 fold higher in non-Cav3 domains with and without TAC, declining about 60% after TAC within each compartment. Mice genetically lacking Cav3 had reduced NO- and BAY-stimulated sGC activity in microdomains containing Cav3 for controls but no change within non-Cav3-enriched domains. CONCLUSIONS Pressure overload depresses NO/heme-dependent sGC activation in the heart, consistent with enhanced oxidation. The data reveal a novel additional mechanism for reduced NO-coupled sGC activity related to dynamic shifts in membrane microdomain localization, with Cav3-microdomains protecting sGC from heme-oxidation and facilitating NO responsiveness. Translocation of sGC out of this domain favors sGC oxidation and contributes to depressed NO-stimulated sGC activity.
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Affiliation(s)
- Emily J. Tsai
- Section in Cardiology, Department of Medicine, Temple University School of Medicine, Philadelphia, PA
- Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, PA
- Division of Cardiology, Department of Medicine, Johns Hopkins University Medical Institutions, Baltimore, MD
| | - Yuchuan Liu
- Cardiovascular Research Center, Temple University School of Medicine, Philadelphia, PA
| | - Norimichi Koitabashi
- Division of Cardiology, Department of Medicine, Johns Hopkins University Medical Institutions, Baltimore, MD
| | - Djahida Bedja
- Department of Comparative Medicine and Comparative Pathology, Johns Hopkins University Medical Institutions, Baltimore, MD 21205
| | - Thomas Danner
- Division of Cardiology, Department of Medicine, Johns Hopkins University Medical Institutions, Baltimore, MD
| | - Jean-Francois Jasmin
- Department of Stem Cell Biology & Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA
| | - Michael P. Lisanti
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, PA
| | - Andreas Friebe
- Physiologisches Institut I, Universität Würzburg, Würzburg, Germany
| | - Eiki Takimoto
- Division of Cardiology, Department of Medicine, Johns Hopkins University Medical Institutions, Baltimore, MD
| | - David A. Kass
- Division of Cardiology, Department of Medicine, Johns Hopkins University Medical Institutions, Baltimore, MD
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248
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Monteiro PF, Morganti RP, Delbin MA, Calixto MC, Lopes-Pires ME, Marcondes S, Zanesco A, Antunes E. Platelet hyperaggregability in high-fat fed rats: a role for intraplatelet reactive-oxygen species production. Cardiovasc Diabetol 2012; 11:5. [PMID: 22248260 PMCID: PMC3320560 DOI: 10.1186/1475-2840-11-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 01/16/2012] [Indexed: 12/27/2022] Open
Abstract
Background Adiposity greatly increases the risk of atherothrombotic events, a pathological condition where a chronic state of oxidative stress is reported to play a major role. This study aimed to investigate the involvement of (NO)-soluble guanylyl cyclase (sGC) signaling pathway in the platelet dysfunction from high fat-fed (HFF) rats. Methods Male Wistar rats were fed for 10 weeks with standard chow (SCD) or high-fat diet (HFD). ADP (10 μM)- and thrombin (100 mU/ml)-induced washed platelet aggregation were evaluated. Measurement of intracellular levels of ROS levels was carried out using flow cytometry. Cyclic GMP levels were evaluated using ELISA kits. Results High-fat fed rats exhibited significant increases in body weight, epididymal fat, fasting glucose levels and glucose intolerance compared with SCD group. Platelet aggregation induced by ADP (n = 8) and thrombin from HFD rats (n = 8) were significantly greater (P < 0.05) compared with SCD group. Platelet activation with ADP increased by 54% the intraplatelet ROS production in HFD group, as measured by flow cytometry (n = 6). N-acetylcysteine (NAC; 1 mM) and PEG-catalase (1000 U/ml) fully prevented the increased ROS production and platelet hyperaggregability in HFD group. The NO donors sodium nitroprusside (SNP; 10 μM) and SNAP (10 μM), as well as the NO-independent soluble guanylyl cyclase stimulator BAY 41-2272 (10 μM) inhibited the platelet aggregation in HFD group with lower efficacy (P < 0.05) compared with SCD group. The cGMP levels in response to these agents were also markedly lower in HFD group (P < 0.05). The prostacyclin analogue iloprost (1 μM) reduced platelet aggregation in HFD and SCD rats in a similar fashion (n = 4). Conclusions Metabolic abnormalities as consequence of HFD cause platelet hyperaggregability involving enhanced intraplatelet ROS production and decreased NO bioavailability that appear to be accompanied by potential defects in the prosthetic haem group of soluble guanylyl cyclase.
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Affiliation(s)
- Priscila F Monteiro
- Department of Pharmacology, University of Campinas, Campinas, Sao Paulo, Brazil
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Perez M, Lakshminrusimha S, Wedgwood S, Czech L, Gugino SF, Russell JA, Farrow KN, Steinhorn RH. Hydrocortisone normalizes oxygenation and cGMP regulation in lambs with persistent pulmonary hypertension of the newborn. Am J Physiol Lung Cell Mol Physiol 2011; 302:L595-603. [PMID: 22198909 DOI: 10.1152/ajplung.00145.2011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In the pulmonary vasculature, cGMP levels are regulated by soluble guanylate cyclase (sGC) and phosphodiesterase 5 (PDE5). We previously reported that lambs with persistent pulmonary hypertension of the newborn (PPHN) demonstrate increased reactive oxygen species (ROS) and altered sGC and PDE5 activity, with resultant decreased cGMP. The objective of this study was to evaluate the effects of hydrocortisone on pulmonary vascular function, ROS, and cGMP in the ovine ductal ligation model of PPHN. PPHN lambs were ventilated with 100% O(2) for 24 h. Six lambs received 5 mg/kg hydrocortisone every 8 h times three doses (PPHN-hiHC), five lambs received 3 mg/kg hydrocortisone followed by 1 mg·kg(-1)·dose(-1) times two doses (PPHN-loHC), and six lambs were ventilated with O(2) alone (PPHN). All groups were compared with healthy 1-day spontaneously breathing lambs (1DSB). O(2) ventilation of PPHN lambs decreased sGC activity, increased PDE5 activity, and increased ROS vs. 1DSB lambs. Both hydrocortisone doses significantly improved arterial-to-alveolar ratios relative to PPHN lambs, decreased PDE5 activity, and increased cGMP relative to PPHN lambs. High-dose hydrocortisone also increased sGC activity, decreased PDE5 expression, decreased ROS, and increased total vascular SOD activity vs. PPHN lambs. These data suggest that hydrocortisone treatment in clinically relevant doses improves oxygenation and decreases hyperoxia-induced changes in sGC and PDE5 activity, increasing cGMP levels. Hydrocortisone reduces ROS levels in part by increasing SOD activity in PPHN lambs ventilated with 100% O(2.) We speculate that hydrocortisone increases cGMP by direct effects on sGC and PDE5 expression and by attenuating abnormalities induced by oxidant stress.
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Affiliation(s)
- Marta Perez
- Northwestern University, Chicago, Illinois, USA.
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250
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Sharina I, Sobolevsky M, Doursout MF, Gryko D, Martin E. Cobinamides are novel coactivators of nitric oxide receptor that target soluble guanylyl cyclase catalytic domain. J Pharmacol Exp Ther 2011; 340:723-32. [PMID: 22171090 DOI: 10.1124/jpet.111.186957] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Soluble guanylyl cyclase (sGC), a ubiquitously expressed heme-containing receptor for nitric oxide (NO), is a key mediator of NO-dependent processes. In addition to NO, a number of synthetic compounds that target the heme-binding region of sGC and activate it in a NO-independent fashion have been described. We report here that dicyanocobinamide (CN2-Cbi), a naturally occurring intermediate of vitamin B(12) synthesis, acts as a sGC coactivator both in vitro and in intact cells. Heme depletion or heme oxidation does not affect CN2-Cbi-dependent activation. Deletion mutagenesis demonstrates that CN2-Cbi targets a new regulatory site and functions though a novel mechanism of sGC activation. Unlike all known sGC regulators that target the N-terminal regulatory regions, CN2-Cbi directly targets the catalytic domain of sGC, resembling the effect of forskolin on adenylyl cyclases. CN2-Cbi synergistically enhances sGC activation by NO-independent regulators 3-(4-amino-5-cyclopropylpyrimidine-2-yl)-1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridine (BAY41-2272), 4-[((4-carboxybutyl){2-[(4-phenethylbenzyl)oxy]phenethyl}amino) methyl [benzoic]-acid (cinaciguat or BAY58-2667), and 5-chloro-2-(5-chloro-thiophene-2-sulfonylamino-N-(4-(morpholine-4-sulfonyl)-phenyl)-benzamide sodium salt (ataciguat or HMR-1766). BAY41-2272 and CN2-Cbi act reciprocally by decreasing the EC(50) values. CN2-Cbi increases intracellular cGMP levels and displays vasorelaxing activity in phenylephrine-constricted rat aortic rings in an endothelium-independent manner. Both effects are synergistically potentiated by BAY41-2272. These studies uncover a new mode of sGC regulation and provide a new tool for understanding the mechanism of sGC activation and function. CN2-Cbi also offers new possibilities for its therapeutic applications in augmenting the effect of other sGC-targeting drugs.
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Affiliation(s)
- Iraida Sharina
- Department of Internal Medicine, Division of Cardiology, UT Health Science Center in Houston, Medical School, 1941 East Rd., Houston, TX 77054, USA
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