1
|
Molecular mechanisms by which iNOS uncoupling can induce cardiovascular dysfunction during sepsis: Role of posttranslational modifications (PTMs). Life Sci 2020; 255:117821. [PMID: 32445759 DOI: 10.1016/j.lfs.2020.117821] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/14/2020] [Accepted: 05/18/2020] [Indexed: 01/01/2023]
Abstract
Human sepsis is the result of a multifaceted pathological process causing marked dysregulation of cardiovascular responses. A more sophisticated understanding of the pathogenesis of sepsis is certainly prerequisite. Evidence from studies provide further insight into the role of inducible nitric oxide synthase (iNOS) isoform. Results on inhibition of iNOS in sepsis models remain inconclusive. Concern has been devoted to improving our knowledge and understanding of the role of iNOS. The aim of this review is to define the role of iNOS in redox homeostasis disturbance, the detailed mechanisms linking iNOS and posttranslational modifications (PTMs) to cardiovascular dysfunctions, and their future implications in sepsis settings. Many questions related to the iNOS and PTMs still remain open, and much more work is needed on this.
Collapse
|
2
|
Heikal L, Starr A, Hussein D, Prieto-Lloret J, Aaronson P, Dailey LA, Nandi M. l-Phenylalanine Restores Vascular Function in Spontaneously Hypertensive Rats Through Activation of the GCH1-GFRP Complex. JACC Basic Transl Sci 2018; 3:366-377. [PMID: 29963647 PMCID: PMC6018612 DOI: 10.1016/j.jacbts.2018.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/27/2017] [Accepted: 01/24/2018] [Indexed: 12/11/2022]
Abstract
Tetrahydrobiopterin is an essential cofactor for NO production. Limitation of endogenous tetrahydrobiopterin reduces NO bioavailability, enhances oxidative stress, and impairs vascular function. Orally supplemented tetrahydrobiopterin has therapeutic challenges because it is rapidly oxidized in vivo. Here, the authors demonstrate that l-phenylalanine, when administered orally, raises vascular tetrahydrobiopterin, restores NO, reduces superoxide, and enhances vascular function in spontaneously hypertensive rats. This effect is achieved by activation of a protein complex (GCH1-GFRP) involved in the biosynthesis of tetrahydrobiopterin. Activation of this protein complex by l-phenylalanine or its analogues represents a novel therapeutic target for vascular disorders underpinned by reduced NO bioavailability.
Reduced nitric oxide (NO) bioavailability correlates with impaired cardiovascular function. NO is extremely labile and has been challenging to develop as a therapeutic agent. However, NO bioavailability could be enhanced by pharmacologically targeting endogenous NO regulatory pathways. Tetrahydrobiopterin, an essential cofactor for NO production, is synthesized by GTP cyclohydrolase-1 (GCH1), which complexes with GCH1 feedback regulatory protein (GFRP). The dietary amino acid l-phenylalanine activates this complex, elevating vascular BH4. Here, the authors demonstrate that l-phenylalanine administration restores vascular function in a rodent model of hypertension, suggesting the GCH1-GFRP complex represents a rational therapeutic target for diseases underpinned by endothelial dysfunction.
Collapse
Key Words
- ACh, acetylcholine
- ANOVA, analysis of variance
- BH2, dihydrobiopterin
- BH4, tetrahydrobiopterin
- EC50, effective concentration for 50% maximal response
- EDHF, endothelium derived hyperpolarizing factor
- GCH1, GTP cyclohydrolase-1
- GFRP, GCH1 feedback regulatory protein
- L-phe, l-phenylalanine
- L-tyr, l-tyrosine
- NO, nitric oxide
- ROS, reactive oxygen species
- SHR, spontaneously hypertensive rat(s)
- WKY, Wistar Kyoto rat(s)
- cardiovascular disease
- eNOS, endothelial nitric oxide synthase
- endothelium
- l-phenylalanine
- nitric oxide
- tetrahydrobiopterin
- vascular activity
Collapse
Affiliation(s)
- Lamia Heikal
- Institute of Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Anna Starr
- Institute of Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Dania Hussein
- Institute of Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Jesus Prieto-Lloret
- Division of Asthma, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Phil Aaronson
- Division of Asthma, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Lea Ann Dailey
- Institute of Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| | - Manasi Nandi
- Institute of Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom.,Cardiovascular Division, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom
| |
Collapse
|
3
|
Perrin-Sarrado C, Dahboul F, Leroy P, Lartaud I. Aging and hypertension decrease endothelial NO-related dilating function and gamma-glutamyl transferase activity but notS-nitrosoglutathione-induced aortic vasodilation. Fundam Clin Pharmacol 2018; 32:134-140. [DOI: 10.1111/fcp.12347] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/10/2017] [Accepted: 12/22/2017] [Indexed: 12/25/2022]
Affiliation(s)
- Caroline Perrin-Sarrado
- EA3452 CITHEFOR ‘Drug Targets, Formulation and Preclinical Assessment’; Faculté de Pharmacie; Université de Lorraine; Nancy France
| | - Fatima Dahboul
- EA3452 CITHEFOR ‘Drug Targets, Formulation and Preclinical Assessment’; Faculté de Pharmacie; Université de Lorraine; Nancy France
| | - Pierre Leroy
- EA3452 CITHEFOR ‘Drug Targets, Formulation and Preclinical Assessment’; Faculté de Pharmacie; Université de Lorraine; Nancy France
| | - Isabelle Lartaud
- EA3452 CITHEFOR ‘Drug Targets, Formulation and Preclinical Assessment’; Faculté de Pharmacie; Université de Lorraine; Nancy France
| |
Collapse
|
4
|
Bouressam ML, Meyer B, Boudier A, Clarot I, Leroy P, Genoni A, Ruiz-Lopez M, Giummelly P, Liminana P, Salgues V, Kouach M, Perrin-Sarrado C, Lartaud I, Dupuis F. In vivo and in silico evaluation of a new nitric oxide donor, S,S′ -dinitrosobucillamine. Nitric Oxide 2017; 71:32-43. [DOI: 10.1016/j.niox.2017.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 09/12/2017] [Accepted: 10/12/2017] [Indexed: 12/15/2022]
|
5
|
Regulation of protein function by S-nitrosation and S-glutathionylation: processes and targets in cardiovascular pathophysiology. Biol Chem 2017; 398:1267-1293. [DOI: 10.1515/hsz-2017-0150] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 08/07/2017] [Indexed: 02/07/2023]
Abstract
AbstractDecades of chemical, biochemical and pathophysiological research have established the relevance of post-translational protein modifications induced by processes related to oxidative stress, with critical reflections on cellular signal transduction pathways. A great deal of the so-called ‘redox regulation’ of cell function is in fact mediated through reactions promoted by reactive oxygen and nitrogen species on more or less specific aminoacid residues in proteins, at various levels within the cell machinery. Modifications involving cysteine residues have received most attention, due to the critical roles they play in determining the structure/function correlates in proteins. The peculiar reactivity of these residues results in two major classes of modifications, with incorporation of NO moieties (S-nitrosation, leading to formation of proteinS-nitrosothiols) or binding of low molecular weight thiols (S-thionylation, i.e. in particularS-glutathionylation,S-cysteinylglycinylation andS-cysteinylation). A wide array of proteins have been thus analyzed in detail as far as their susceptibility to either modification or both, and the resulting functional changes have been described in a number of experimental settings. The present review aims to provide an update of available knowledge in the field, with a special focus on the respective (sometimes competing and antagonistic) roles played by proteinS-nitrosations andS-thionylations in biochemical and cellular processes specifically pertaining to pathogenesis of cardiovascular diseases.
Collapse
|
6
|
Perrin-Sarrado C, Pongas M, Dahboul F, Leroy P, Pompella A, Lartaud I. Reduced Activity of the Aortic Gamma-Glutamyltransferase Does Not Decrease S-Nitrosoglutathione Induced Vasorelaxation of Rat Aortic Rings. Front Physiol 2017; 7:630. [PMID: 28066263 PMCID: PMC5168561 DOI: 10.3389/fphys.2016.00630] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 12/05/2016] [Indexed: 12/28/2022] Open
Abstract
Aims: Gamma-glutamyl transferase (GGT), an enzyme present on the endothelium, is involved in the release of nitric oxide (NO) from S-nitrosoglutathione (GSNO) and in the GSNO-induced vasodilation. Endogenous GSNO is a physiological storage form of NO in tissues while exogenous GSNO is an interesting candidate for compensating for the decreased NO bioavailability occurring during cardiovascular diseases. We investigated in a rat model of human hypertension, the spontaneous hypertensive rat (SHR), submitted or not to high salt diet, whether a decreased vascular GGT activity modifies the vasorelaxant effect of GSNO. Methods: Thoracic aortic rings isolated from male SHR and Wistar Kyoto rats (WKY) aged 20–22 weeks—submitted or not for 8 weeks to a high salt diet (1% w/v NaCl in drinking water) were pre-constricted with phenylephrine then submitted to concentration-vasorelaxant response curves (maximal response: Emax; pD2) to carbachol or sodium nitroprusside to evaluate endothelial dependent or independent NO-induced vasodilation, or GSNO (exogenous NO vasodilation depending from the endothelial GGT activity). GGT activity was measured using a chromogenic substrate in aortic homogenates. Its role in GSNO-induced relaxation was assessed following inhibition of the enzyme activity (serine-borate complex). That of protein disulfide isomerase (PDI), another redox sensitive enzyme involved in GSNO metabolism, was assessed following inhibition with bacitracin. Results: Aortic GGT activity (18–23 μmol/min/mg of tissue in adult WKY) decreased by 33% in SHR and 45% in SHR with high salt diet. Emax and pD2 for sodium nitroprusside were similar in all groups. Emax for carbachol decreased by −14%, reflecting slight endothelial NO-dependent dysfunction. The GSNO curve was slightly shifted to the left in SHR and in SHR with high salt diet, showing a small enhanced sensitivity to GSNO. Involvements of GGT, as that of PDI, in the GSNO effects were similar in all groups (pD2 for GSNO −0.5 to −1.5 following enzymatic inhibition). Conclusion: Hypertension is associated with a decreased aortic GGT activity without decreasing the vasorelaxant effects of GSNO, whose bioactivity may be supplemented through the alternative enzymatic activity of PDI.
Collapse
Affiliation(s)
- Caroline Perrin-Sarrado
- EA3452 CITHEFOR "Drug Targets, Formulation and Preclinical Assessment", Faculté de Pharmacie, Université de Lorraine Nancy, France
| | - Marios Pongas
- EA3452 CITHEFOR "Drug Targets, Formulation and Preclinical Assessment", Faculté de Pharmacie, Université de Lorraine Nancy, France
| | - Fatima Dahboul
- EA3452 CITHEFOR "Drug Targets, Formulation and Preclinical Assessment", Faculté de Pharmacie, Université de Lorraine Nancy, France
| | - Pierre Leroy
- EA3452 CITHEFOR "Drug Targets, Formulation and Preclinical Assessment", Faculté de Pharmacie, Université de Lorraine Nancy, France
| | - Alfonso Pompella
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa Medical School Pisa, Italy
| | - Isabelle Lartaud
- EA3452 CITHEFOR "Drug Targets, Formulation and Preclinical Assessment", Faculté de Pharmacie, Université de Lorraine Nancy, France
| |
Collapse
|
7
|
Rychter M, Gaucher C, Boudier A, Leroy P, Lulek J. S -Nitrosothiols—NO donors regulating cardiovascular cell proliferation: Insight into intracellular pathway alterations. Int J Biochem Cell Biol 2016; 78:156-161. [DOI: 10.1016/j.biocel.2016.07.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Revised: 07/04/2016] [Accepted: 07/05/2016] [Indexed: 01/20/2023]
|
8
|
Heikal L, Starr A, Martin GP, Nandi M, Dailey LA. In vivo pharmacological activity and biodistribution of S-nitrosophytochelatins after intravenous and intranasal administration in mice. Nitric Oxide 2016; 59:1-9. [PMID: 27350118 PMCID: PMC5045922 DOI: 10.1016/j.niox.2016.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 06/23/2016] [Indexed: 01/21/2023]
Abstract
S-nitrosophytochelatins (SNOPCs) are novel analogues of S-nitrosoglutathione (GSNO) with the advantage of carrying varying ratios of S-nitrosothiol (SNO) moieties per molecule. Our aim was to investigate the in vivo pharmacological potency and biodistribution of these new GSNO analogues after intravenous (i.v.) and intranasal (i.n.) administration in mice. SNOPCs with either two or six SNO groups and GSNO were synthesized and characterized for purity. Compounds were administered i.v. or i.n. at 1 μmol NO/kg body weight to CD-1 mice. Blood pressure was measured and biodistribution studies of total nitrate and nitrite species (NOx) and phytochelatins were performed after i.v. administration. At equivalent doses of NO, it was observed that SNOPC-6 generated a rapid and significantly greater reduction in blood pressure (∼60% reduction compared to saline) whereas GSNO and SNOPC-2 only achieved a 30-35% decrease. The reduction in blood pressure was transient and recovered to baseline levels within ∼2 min for all compounds. NOx species were transiently elevated (over 5 min) in the plasma, lung, heart and liver. Interestingly, a size-dependent phytochelatin accumulation was observed in several tissues including the heart, lungs, kidney, brain and liver. Biodistribution profiles of NOx were also obtained after i.n. administration, showing significant lung retention of NOx over 15 min with minor systemic increases observed from 5 to 15 min. In summary, this study has revealed interesting in vivo pharmacological properties of SNOPCs, with regard to their dramatic hypotensive effects and differing biodistribution patterns following two different routes of administration.
Collapse
Affiliation(s)
- Lamia Heikal
- Institute of Pharmaceutical Sciences, Faculty of Life Science & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| | - Anna Starr
- Institute of Pharmaceutical Sciences, Faculty of Life Science & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| | - Gary P Martin
- Institute of Pharmaceutical Sciences, Faculty of Life Science & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| | - Manasi Nandi
- Institute of Pharmaceutical Sciences, Faculty of Life Science & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK.
| | - Lea Ann Dailey
- Institute of Pharmaceutical Sciences, Faculty of Life Science & Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK
| |
Collapse
|
9
|
Time lasting S-nitrosoglutathione polymeric nanoparticles delay cellular protein S-nitrosation. Eur J Pharm Biopharm 2014; 89:1-8. [PMID: 25448077 DOI: 10.1016/j.ejpb.2014.11.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/07/2014] [Accepted: 11/09/2014] [Indexed: 11/22/2022]
Abstract
Physiological S-nitrosothiols (RSNO), such as S-nitrosoglutathione (GSNO), can be used as nitric oxide (NO) donor for the treatment of vascular diseases. However, despite a half-life measured in hours, the stability of RSNO, limited by enzymatic and non-enzymatic degradations, is too low for clinical application. So, to provide a long-lasting effect and to deliver appropriate NO concentrations to target tissues, RSNO have to be protected. RSNO encapsulation is an interesting response to overcome degradation and provide protection. However, RSNO such as GSNO raise difficulties for encapsulation due to its hydrophilic nature and the instability of the S-NO bound during the formulation process. To our knowledge, the present study is the first description of the direct encapsulation of GSNO within polymeric nanoparticles (NP). The GSNO-loaded NP (GSNO-NP) formulated by a double emulsion process, presented a mean diameter of 289 ± 7 nm. They were positively charged (+40 mV) due to the methacrylic acid and ethylacrylate polymer (Eudragit® RL) used and encapsulated GSNO with a satisfactory efficiency (i.e. 54% or 40 mM GSNO loaded in the NP). In phosphate buffer (37 °C; pH 7.4), GSNO-NP released 100% of encapsulated GSNO within 3h and remained stable still 6h. However, in contact with smooth muscle cells, maximum protein nitrosation (a marker of NO bioavailability) was delayed from 1h for free GSNO to 18h for GSNO-NP. Therefore, protection and sustained release of NO were achieved by the association of a NO donor with a drug delivery system (such as polymeric NP), providing opportunities for vascular diseases treatment.
Collapse
|
10
|
Dahboul F, Perrin-Sarrado C, Boudier A, Lartaud I, Schneider R, Leroy P. S,S′-dinitrosobucillamine, a new nitric oxide donor, induces a better vasorelaxation than other S-nitrosothiols. Eur J Pharmacol 2014; 730:171-9. [DOI: 10.1016/j.ejphar.2014.02.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 02/21/2014] [Accepted: 02/28/2014] [Indexed: 02/05/2023]
|
11
|
de Mel A, Naghavi N, Cousins BG, Clatworthy I, Hamilton G, Darbyshire A, Seifalian AM. Nitric oxide-eluting nanocomposite for cardiovascular implants. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2014; 25:917-929. [PMID: 24293239 DOI: 10.1007/s10856-013-5103-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 11/18/2013] [Indexed: 06/02/2023]
Abstract
Cardiovascular implants must resist thrombosis and intimal hyperplasia, but they are prone to such patency limiting conditions during graft implantation and prior to endothelialisation. Nitric oxide (NO) released from the endothelium has a complex protective role in the cardiovascular system, and this study has addressed: (1) in situ NO release profiles from S-nitrosothiols ((S-Nitroso-N-acetylpenicillamine (SNAP) and (S-Nitrosoglutathione (GSNO)) incorporated into polyhedral oligomeric silsesquioxanepoly(carbonate-urea)urethane (POSS-PCU) coronary artery bypass grafts (CABG) in a physiological pulsatile flow, and (2) the determination of their interaction with endothelial progenitor cells (EPCs), smooth muscle cells, platelets, whole blood kinetics. It was found that 1, 2, and 3 wt% SNAP/GSNO incorporated into POSS-PCU-CABG successfully eluted NO, but optimal elution was evident with 2 %-SNAP-POSS-PCU. NO release determined under static conditions using the Griess assay, and in situ measurements under pulsatile flow using amperometric probe was found to differ, thus confirming the significance of monitoring NO-elution under haemodynamic conditions. 2 %-SNAP-POSS-PCU demonstrated anti-thrombogenic kinetics through thromboelastography measurements, while metabolic activity using Alamar Blue™ assay and scanning electron microscopy demonstrated greater adhesion of EPCs and reduced adhesion of platelets.
Collapse
Affiliation(s)
- Achala de Mel
- Centre for Nanotechnology & Regenerative Medicine, University College London, London, UK
| | | | | | | | | | | | | |
Collapse
|
12
|
Chou HC, Chiu SJ, Liu YL, Hu TM. Direct formation of S-nitroso silica nanoparticles from a single silica source. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:812-822. [PMID: 24410024 DOI: 10.1021/la4048215] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Nitric oxide (NO) is a ubiquitous molecule in the body. Because of its multiple pathophysiologic roles, the potential for treating various diseases by the exogenous administration of NO has been under intensive investigation. However, the unstable, radical nature of NO poses a major challenge to the effective delivery of NO. Previously, silica nanoparticles synthesized by the traditional method have been developed into NO-carrying systems. In the present study, for the first time NO-carrying silica nanoparticles were prepared from a single silica precursor using a simple nanoprecipitation method. (3-Mercaptopropyl)-trimethoxysilane (MPTMS) was used as the sole silane source, which was subjected to acid-catalyzed S-nitrosation and condensation reactions in a one-pot organic phase. S-Nitroso silica nanoparticles (SNO-SiNPs) were then produced by injecting a smaller quantity of the organic phase into a larger amount of water without surfactants. Various preparation parameters were tested to obtain optimized conditions. Moreover, a phase diagram demonstrating the ouzo effect was constructed. The prepared SNO-SiNPs were spherical particles with a tunable size in the range of 100-400 nm. The nanoparticles in aqueous dispersions exhibited high colloid stability, possibly resulting from highly negatively charged surfaces. The result of solid-state (29)Si NMR shows the predominance of T(2) and T(3) silicon structures, suggesting that nanoparticles were formed from polycondensed silica species. In conclusion, NO-loaded silica nanoparticles have been directly prepared from a single silane precursor using a surfactant-free, low-energy, one-step nanoprecipitation approach. The method precludes the need for the initial formation of bare particles and subsequent functionalization steps.
Collapse
Affiliation(s)
- Hung-Chang Chou
- School of Pharmacy, National Defense Medical Center , Taipei 11490, Taiwan, ROC
| | | | | | | |
Collapse
|
13
|
Dahboul F, Leroy P, Maguin Gate K, Boudier A, Gaucher C, Liminana P, Lartaud I, Pompella A, Perrin-Sarrado C. Endothelial γ-glutamyltransferase contributes to the vasorelaxant effect of S-nitrosoglutathione in rat aorta. PLoS One 2012; 7:e43190. [PMID: 22984412 PMCID: PMC3439434 DOI: 10.1371/journal.pone.0043190] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 07/20/2012] [Indexed: 11/28/2022] Open
Abstract
S-nitrosoglutathione (GSNO) involved in storage and transport of nitric oxide (•NO) plays an important role in vascular homeostasis. Breakdown of GSNO can be catalyzed by γ-glutamyltransferase (GGT). We investigated whether vascular GGT influences the vasorelaxant effect of GSNO in isolated rat aorta. Histochemical localization of GGT and measurement of its activity were performed by using chromogenic substrates in sections and in aorta homogenates, respectively. The role of GGT in GSNO metabolism was evaluated by measuring GSNO consumption rate (absorbance decay at 334 nm), •NO release was visualized and quantified with the fluorescent probe 4,5-diaminofluorescein diacetate. The vasorelaxant effect of GSNO was assayed using isolated rat aortic rings (in the presence or absence of endothelium). The role of GGT was assessed by stimulating enzyme activity with cosubstrate glycylglycine, as well as using two independent inhibitors, competitive serine borate complex and non-competitive acivicin. Specific GGT activity was histochemically localized in the endothelium. Consumption of GSNO and release of free •NO decreased and increased in presence of serine borate complex and glycylglycine, respectively. In vasorelaxation experiments with endothelium-intact aorta, the half maximal effective concentration of GSNO (EC50 = 3.2±0.5.10−7 M) increased in the presence of the two distinct GGT inhibitors, serine borate complex (1.6±0.2.10−6 M) and acivicin (8.3±0.6.10−7 M), while it decreased with glycylglycine (4.7±0.9.10−8 M). In endothelium-denuded aorta, EC50 for GSNO alone increased to 2.3±0.3.10−6 M, with no change in the presence of serine borate complex. These data demonstrate the important role of endothelial GGT activity in mediating the vasorelaxant effect of GSNO in rat aorta under physiological conditions. Because therapeutic treatments based on GSNO are presently under development, this endothelium-dependent mechanism involved in the vascular effects of GSNO should be taken into account in a pharmacological perspective.
Collapse
Affiliation(s)
- Fatima Dahboul
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Pierre Leroy
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Katy Maguin Gate
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Ariane Boudier
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Caroline Gaucher
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Patrick Liminana
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Isabelle Lartaud
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Alfonso Pompella
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
| | - Caroline Perrin-Sarrado
- EA3452 CITHEFOR “Drug targets, formulation and preclinical assessment”, Faculté de Pharmacie, Université de Lorraine, Nancy, France
- * E-mail:
| |
Collapse
|