151
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Lundberg JO, Gladwin MT, Weitzberg E. Strategies to increase nitric oxide signalling in cardiovascular disease. Nat Rev Drug Discov 2015; 14:623-41. [PMID: 26265312 DOI: 10.1038/nrd4623] [Citation(s) in RCA: 376] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nitric oxide (NO) is a key signalling molecule in the cardiovascular, immune and central nervous systems, and crucial steps in the regulation of NO bioavailability in health and disease are well characterized. Although early approaches to therapeutically modulate NO bioavailability failed in clinical trials, an enhanced understanding of fundamental subcellular signalling has enabled a range of novel therapeutic approaches to be identified. These include the identification of: new pathways for enhancing NO synthase activity; ways to amplify the nitrate-nitrite-NO pathway; novel classes of NO-donating drugs; drugs that limit NO metabolism through effects on reactive oxygen species; and ways to modulate downstream phosphodiesterases and soluble guanylyl cyclases. In this Review, we discuss these latest developments, with a focus on cardiovascular disease.
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Affiliation(s)
- Jon O Lundberg
- Department of Physiology and Pharmacology, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | - Mark T Gladwin
- Vascular Medicine Institute, Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pennsylvania 15213, USA
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Karolinska Institute, SE-171 77 Stockholm, Sweden
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152
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Huang CY, Wang LC, Shan YS, Pan CH, Tsai KJ. Memantine Attenuates Delayed Vasospasm after Experimental Subarachnoid Hemorrhage via Modulating Endothelial Nitric Oxide Synthase. Int J Mol Sci 2015; 16:14171-80. [PMID: 26110388 PMCID: PMC4490546 DOI: 10.3390/ijms160614171] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/09/2015] [Accepted: 06/16/2015] [Indexed: 01/01/2023] Open
Abstract
Delayed cerebral vasospasm is an important pathological feature of subarachnoid hemorrhage (SAH). The cause of vasospasm is multifactorial. Impairs nitric oxide availability and endothelial nitric oxide synthase (eNOS) dysfunction has been reported to underlie vasospasm. Memantine, a low-affinity uncompetitive N-methyl-d-aspartate (NMDA) blocker has been proven to reduce early brain injury after SAH. This study investigated the effect of memantine on attenuation of vasospasm and restoring eNOS functionality. Male Sprague-Dawley rats weighing 350–450 g were randomly divided into three weight-matched groups, sham surgery, SAH + vehicle, and SAH + memantine groups. The effects of memantine on SAH were evaluated by assessing the severity of vasospasm and the expression of eNOS. Memantine effectively ameliorated cerebral vasospasm by restoring eNOS functionality. Memantine can prevent vasospasm in experimental SAH. Treatment strategies may help combat SAH-induced vasospasm in the future.
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Affiliation(s)
- Chih-Yuan Huang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
- Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
| | - Liang-Chao Wang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
- Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
| | - Yan-Shen Shan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
- Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
| | - Chia-Hsin Pan
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
| | - Kuen-Jer Tsai
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
- Center of Clinical Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.
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153
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Unnikrishnan B, Wei SC, Chiu WJ, Cang J, Hsu PH, Huang CC. Nitrite ion-induced fluorescence quenching of luminescent BSA-Au(25) nanoclusters: mechanism and application. Analyst 2015; 139:2221-8. [PMID: 24634911 DOI: 10.1039/c3an02291a] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fluorescence quenching is an interesting phenomenon which is highly useful in developing fluorescence based sensors. A thorough understanding of the fluorescence quenching mechanism is essential to develop efficient sensors. In this work, we investigate different aspects governing the nitrite ion-induced fluorescence quenching of luminescent bovine serum albumin stabilized gold nanoclusters (BSA-Au NCs) and their application for detection of nitrite in urine. The probable events leading to photoluminescence (PL) quenching by nitrite ions were discussed on the basis of the results obtained from ultraviolet-visible (UV-Vis) absorption spectroscopy, X-ray photoelectron spectroscopy (XPS), fluorescence measurements, circular dichroism (CD) spectroscopy, zeta potential and dynamic light scattering (DLS) studies. These studies suggested that PL quenching mainly occurred through the oxidation of Au(0) atoms to Au(i) atoms in the core of BSA-Au NCs mediated by nitrite ions. The interference caused by certain species such as Hg(2+), Cu(2+), CN(-), S(2-), glutathione, cysteine, etc. during the nitrite determination by fluorescence quenching was eliminated by using masking agents and optimising the conditions. Based on these findings we proposed a BSA-Au NC-modified membrane based sensor which would be more convenient for the real life applications such as nitrite detection in urine samples. The BSA-Au NC-modified nitrocellulose membrane (NCM) enabled the detection of nitrite at a level as low as 100 nM in aqueous solutions. This Au NC-based paper probe was validated to exhibit good performance for nitrite analysis in environmental water and urine samples, which makes it useful in practical applications.
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Affiliation(s)
- Binesh Unnikrishnan
- Institute of Bioscience and Biotechnology, National Taiwan Ocean University, 20224, Keelung, Taiwan.
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154
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Kuzenkov VS, Krushinskii AL. Effect of Sodium Nitrite and L-NNA on the Outcome of Experimental Ischemic Stroke. Bull Exp Biol Med 2015; 159:217-20. [PMID: 26085355 DOI: 10.1007/s10517-015-2926-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Indexed: 11/26/2022]
Abstract
We studied the effect of sodium nitrite in doses of 5 and 50 mg/kg and NO synthase inhibitor L-NNA in a dose of 20 mg/kg on the course of experimental ischemic stroke caused by occlusion of both carotid arteries. Sodium nitrite and NO synthase inhibitor were administered 1 h prior to occlusion of еру carotid arteries and 5 sec after brain ischemia. Sodium nitrite in a dose of 5 mg/kg had a protective effect on the time course of neurological disorders and reduced animal mortality. NO synthase inhibitor L-NNA aggravated the neurological symptoms.
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Affiliation(s)
- V S Kuzenkov
- Biological Faculty, M. V. Lomonosov Moscow State University, Moscow, Russia,
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155
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Electrochemical assay for the determination of nitric oxide metabolites using copper(II) chlorophyllin modified screen printed electrodes. Anal Biochem 2015; 478:121-7. [DOI: 10.1016/j.ab.2015.01.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/22/2015] [Accepted: 01/30/2015] [Indexed: 12/19/2022]
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156
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Convergence of biological nitration and nitrosation via symmetrical nitrous anhydride. Nat Chem Biol 2015; 11:504-10. [PMID: 26006011 PMCID: PMC4472503 DOI: 10.1038/nchembio.1814] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 04/06/2015] [Indexed: 02/06/2023]
Abstract
Current perspective holds that the generation of secondary signaling mediators from nitrite (NO2−) requires acidification to nitrous acid (HNO2) or metal catalysis. Herein, the use of stable isotope-labeled NO2− and LC-MS/MS analysis of products revealed that NO2− also participates in fatty acid nitration and thiol S-nitrosation at neutral pH. These reactions occur in the absence of metal centers and are stimulated by nitric oxide (•NO) autoxidation via symmetrical dinitrogen trioxide (nitrous anhydride, symN2O3) formation. While theoretical models have predicted physiological symN2O3 formation, its generation is now demonstrated in aqueous reaction systems, cell models and in viv, with the concerted reactions of •NO and NO2− shown to be critical for symN2O3 formation. These results reveal new mechanisms underlying the NO2− propagation of •NO signaling and the regulation of both biomolecule function and signaling network activity via NO2−-dependent nitrosation and nitration reactions.
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157
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Thomas DD. Breathing new life into nitric oxide signaling: A brief overview of the interplay between oxygen and nitric oxide. Redox Biol 2015; 5:225-233. [PMID: 26056766 PMCID: PMC4473092 DOI: 10.1016/j.redox.2015.05.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 05/18/2015] [Indexed: 02/04/2023] Open
Abstract
Nitric oxide (•NO, nitrogen monoxide) is one of the most unique biological signaling molecules associated with a multitude of physiologic and pathological conditions. In order to fully appreciate its numerous roles, it is essential to understand its basic biochemical properties. Most signaling effector molecules such as steroids or proteins have a significant life-span and function through classical receptor–ligand interactions. •NO, however, is a short-lived free-radical gas that only reacts with two types of molecules under biological conditions; metals and other free radicals. These simple interactions can lead to a myriad of complex intermediates which in turn have their own phenotypic effects. For these reasons, responses to •NO often appear to be random or contradictory when outcomes are compared across various experimental settings. This article will serve as a brief overview of the chemical, biological, and microenvironmental factors that dictate •NO signaling with an emphasis on •NO metabolism. The prominent role that oxygen (dioxygen, O2) plays in •NO metabolism and how it influences the biological effects of •NO will be highlighted. This information and these concepts are intended to help students and investigators think about the interpretation of data from experiments where biological effects of •NO are being elucidated. Oxygen is a major determinant of the rates of nitric oxide synthesis and metabolism. Under biological conditions nitric oxide only reacts with metals and other free radicals. Oxygen determines the half-life, concentration, and diffusional distance of nitric oxide. Proteins respond to nitric oxide in a concentration and time-dependent manner. Oxygen and the redox environment will greatly influence signaling responses to nitric oxide.
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Affiliation(s)
- Douglas D Thomas
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 S. Wood Street, MC 781, Chicago, IL 60612, USA.
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158
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Hematian S, Kenkel I, Shubina TE, Dürr M, Liu JJ, Siegler MA, Ivanovic-Burmazovic I, Karlin KD. Nitrogen Oxide Atom-Transfer Redox Chemistry; Mechanism of NO(g) to Nitrite Conversion Utilizing μ-oxo Heme-Fe(III)-O-Cu(II)(L) Constructs. J Am Chem Soc 2015; 137:6602-15. [PMID: 25974136 DOI: 10.1021/jacs.5b02174] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
While nitric oxide (NO, nitrogen monoxide) is a critically important signaling agent, its cellular concentrations must be tightly controlled, generally through its oxidative conversion to nitrite (NO2(-)) where it is held in reserve to be reconverted as needed. In part, this reaction is mediated by the binuclear heme a3/CuB active site of cytochrome c oxidase. In this report, the oxidation of NO(g) to nitrite is shown to occur efficiently in new synthetic μ-oxo heme-Fe(III)-O-Cu(II)(L) constructs (L being a tridentate or tetradentate pyridyl/alkylamino ligand), and spectroscopic and kinetic investigations provide detailed mechanistic insights. Two new X-ray structures of μ-oxo complexes have been determined and compared to literature analogs. All μ-oxo complexes react with 2 mol equiv NO(g) to give 1:1 mixtures of discrete [(L)Cu(II)(NO2(-))](+) plus ferrous heme-nitrosyl compounds; when the first NO(g) equiv reduces the heme center and itself is oxidized to nitrite, the second equiv of NO(g) traps the ferrous heme thus formed. For one μ-oxo heme-Fe(III)-O-Cu(II)(L) compound, the reaction with NO(g) reveals an intermediate species ("intermediate"), formally a bis-NO adduct, [(NO)(porphyrinate)Fe(II)-(NO2(-))-Cu(II)(L)](+) (λmax = 433 nm), confirmed by cryo-spray ionization mass spectrometry and EPR spectroscopy, along with the observation that cooling a 1:1 mixture of [(L)Cu(II)(NO2(-))](+) and heme-Fe(II)(NO) to -125 °C leads to association and generation of the key 433 nm UV-vis feature. Kinetic-thermodynamic parameters obtained from low-temperature stopped-flow measurements are in excellent agreement with DFT calculations carried out which describe the sequential addition of NO(g) to the μ-oxo complex.
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Affiliation(s)
- Shabnam Hematian
- †Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21211, United States
| | - Isabell Kenkel
- ‡Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Erlangen 91058, Germany
| | - Tatyana E Shubina
- ‡Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Erlangen 91058, Germany
| | - Maximilian Dürr
- ‡Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Erlangen 91058, Germany
| | - Jeffrey J Liu
- †Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21211, United States
| | - Maxime A Siegler
- †Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21211, United States
| | | | - Kenneth D Karlin
- †Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21211, United States
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159
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Rocha BS, Gago B, Barbosa RM, Cavaleiro C, Laranjinha J. Ethyl nitrite is produced in the human stomach from dietary nitrate and ethanol, releasing nitric oxide at physiological pH: potential impact on gastric motility. Free Radic Biol Med 2015; 82:160-6. [PMID: 25645954 DOI: 10.1016/j.freeradbiomed.2015.01.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/12/2015] [Accepted: 01/13/2015] [Indexed: 02/01/2023]
Abstract
BACKGROUND Nitric oxide ((∙)NO), a ubiquitous molecule involved in a plethora of signaling pathways, is produced from dietary nitrate in the gut through the so-called nitrate-nitrite-NO pathway. In the stomach, nitrite derived from dietary nitrate triggers a network of chemical reactions targeting endogenous and exogenous biomolecules, thereby producing new compounds with physiological activity. OBJECTIVE The aim of this study was to ascertain whether compounds with physiological relevance are produced in the stomach upon consumption of nitrate- and ethanol-rich foods. DESIGN Human volunteers consumed a serving of lettuce (source of nitrate) and alcoholic beverages (source of ethanol). After 15 min, samples of the gastric headspace were collected and ethyl nitrite was identified by GC-MS. Wistar rats were used to study the impact of ethyl nitrite on gastric smooth muscle relaxation at physiological pH. RESULT Nitrogen oxides, produced from nitrite in the stomach, induce nitrosation of ethanol from alcoholic beverages in the human stomach yielding ethyl nitrite. Ethyl nitrite, a potent vasodilator, is produced in vivo upon the consumption of lettuce with either red wine or whisky. Moreover, at physiological pH, ethyl nitrite induces gastric smooth muscle relaxation through a cGMP-dependent pathway. Overall, these results suggest that ethyl nitrite is produced in the gastric lumen and releases (∙)NO at physiological pH, which ultimately may have an impact on gastric motility. Systemic effects may also be expected if ethyl nitrite diffuses through the gastric mucosa reaching blood vessels, therefore operating as a (∙)NO carrier throughout the body. CONCLUSION These data pinpoint posttranslational modifications as an underappreciated mechanism for the production of novel molecules with physiological impact locally in the gut and highlight the notion that diet may fuel compounds with the potential to modulate gastrointestinal welfare.
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Affiliation(s)
- Bárbara S Rocha
- Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Bruno Gago
- Department of Health Sciences, University of Aveiro, Aveiro, Portugal
| | - Rui M Barbosa
- Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Carlos Cavaleiro
- Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, 3000-548 Coimbra, Portugal
| | - João Laranjinha
- Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, 3000-548 Coimbra, Portugal.
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160
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Nielsen PM, Fago A. Inhibitory effects of nitrite on the reactions of bovine carbonic anhydrase II with CO2 and bicarbonate consistent with zinc-bound nitrite. J Inorg Biochem 2015; 149:6-11. [PMID: 25951615 DOI: 10.1016/j.jinorgbio.2015.04.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/21/2015] [Accepted: 04/21/2015] [Indexed: 11/28/2022]
Abstract
Carbonic anhydrase (CA) is a zinc enzyme that catalyzes hydration of carbon dioxide (CO2) and dehydration of bicarbonate in red blood cells, thus facilitating CO2 transport and excretion. Bovine CA II may also react with nitrite to generate nitric oxide, although nitrite is a known inhibitor of the CO2 hydration reaction. To address the potential in vivo interference of these reactions and the nature of nitrite binding to the enzyme, we here investigate the inhibitory effect of 10-30 mM nitrite on Michaelis-Menten kinetics of CO2 hydration and bicarbonate dehydration by stopped-flow spectroscopy. Our data show that nitrite significantly affects the apparent dissociation constant KM for CO2 (11 mM) and bicarbonate (221 mM), and the turnover number kcat for the CO2 hydration (1.467 × 10(6) s(-1)) but not for the bicarbonate dehydration (7.927 × 10(5) s(-1)). These effects demonstrate mixed and competitive inhibition for the reaction with CO2 and bicarbonate, respectively, and are consistent with nitrite binding to the active site zinc. The high apparent dissociation constant found here for CO2, bicarbonate and nitrite (16-120 mM) are all overall consistent with published data and reveal a large capacity of free enzyme available for binding each of the three substrates at their in vivo levels, with little or no significant interference among reactions. The low affinity of the enzyme for nitrite suggests that the in vivo interaction between red blood cell CA II and nitrite requires compartmentalization at the anion exchanger protein of the red cell membrane to be physiologically relevant.
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Affiliation(s)
- Per M Nielsen
- Department of Bioscience, Aarhus University, C.F. Møllers Alle 3, DK-8000 Aarhus C, Denmark.
| | - Angela Fago
- Department of Bioscience, Aarhus University, C.F. Møllers Alle 3, DK-8000 Aarhus C, Denmark.
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161
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Bailey SJ, Varnham RL, DiMenna FJ, Breese BC, Wylie LJ, Jones AM. Inorganic nitrate supplementation improves muscle oxygenation, O₂ uptake kinetics, and exercise tolerance at high but not low pedal rates. J Appl Physiol (1985) 2015; 118:1396-405. [PMID: 25858494 DOI: 10.1152/japplphysiol.01141.2014] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 04/05/2015] [Indexed: 02/03/2023] Open
Abstract
We tested the hypothesis that inorganic nitrate (NO3 (-)) supplementation would improve muscle oxygenation, pulmonary oxygen uptake (V̇o2) kinetics, and exercise tolerance (Tlim) to a greater extent when cycling at high compared with low pedal rates. In a randomized, placebo-controlled cross-over study, seven subjects (mean ± SD, age 21 ± 2 yr, body mass 86 ± 10 kg) completed severe-intensity step cycle tests at pedal cadences of 35 rpm and 115 rpm during separate nine-day supplementation periods with NO3 (-)-rich beetroot juice (BR) (providing 8.4 mmol NO3 (-)/day) and placebo (PLA). Compared with PLA, plasma nitrite concentration increased 178% with BR (P < 0.01). There were no significant differences in muscle oxyhemoglobin concentration ([O2Hb]), phase II V̇o2 kinetics, or Tlim between BR and PLA when cycling at 35 rpm (P > 0.05). However, when cycling at 115 rpm, muscle [O2Hb] was higher at baseline and throughout exercise, phase II V̇o2 kinetics was faster (47 ± 16 s vs. 61 ± 25 s; P < 0.05), and Tlim was greater (362 ± 137 s vs. 297 ± 79 s; P < 0.05) with BR compared with PLA. These results suggest that short-term BR supplementation can increase muscle oxygenation, expedite the adjustment of oxidative metabolism, and enhance exercise tolerance when cycling at a high, but not a low, pedal cadence in healthy recreationally active subjects. These findings support recent observations that NO3 (-) supplementation may be particularly effective at improving physiological and functional responses in type II muscle fibers.
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Affiliation(s)
- Stephen J Bailey
- Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK;
| | - Richard L Varnham
- Sport and Health Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford, UK
| | - Fred J DiMenna
- Teachers College, Department of Biobehavioral Sciences, Columbia University, New York, New York; and
| | - Brynmor C Breese
- School of Biological and Biomedical Sciences, Plymouth University, Plymouth, UK
| | - Lee J Wylie
- Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Andrew M Jones
- Sport and Health Sciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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162
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Dyakova EY, Kapilevich LV, Shylko VG, Popov SV, Anfinogenova Y. Physical exercise associated with NO production: signaling pathways and significance in health and disease. Front Cell Dev Biol 2015; 3:19. [PMID: 25883934 PMCID: PMC4382985 DOI: 10.3389/fcell.2015.00019] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 03/07/2015] [Indexed: 12/20/2022] Open
Abstract
Here we review available data on nitric oxide (NO)-mediated signaling in skeletal muscle during physical exercise. Nitric oxide modulates skeletal myocyte function, hormone regulation, and local microcirculation. Nitric oxide underlies the therapeutic effects of physical activity whereas the pharmacological modulators of NO-mediated signaling are the promising therapeutic agents in different diseases. Nitric oxide production increases in skeletal muscle in response to physical activity. This molecule can alter energy supply in skeletal muscle through hormonal modulation. Mitochondria in skeletal muscle tissue are highly abundant and play a pivotal role in metabolism. Considering NO a plausible regulator of mitochondrial biogenesis that directly affects cellular respiration, we discuss the mechanisms of NO-induced mitochondrial biogenesis in the skeletal muscle cells. We also review available data on myokines, the molecules that are expressed and released by the muscle fibers and exert autocrine, paracrine and/or endocrine effects. The article suggests the presence of putative interplay between NO-mediated signaling and myokines in skeletal muscle. Data demonstrate an important role of NO in various diseases and suggest that physical training may improve health of patients with diabetes, chronic heart failure, and even degenerative muscle diseases. We conclude that NO-associated signaling represents a promising target for the treatment of various diseases and for the achievement of better athletic performance.
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Affiliation(s)
- Elena Y Dyakova
- Department of Sporting Health Tourism, Physiology, and Medicine, National Research Tomsk State University Tomsk, Russia
| | - Leonid V Kapilevich
- Department of Sporting Health Tourism, Physiology, and Medicine, National Research Tomsk State University Tomsk, Russia ; Institute of Physics and Technology, National Research Tomsk Polytechnic University Tomsk, Russia
| | - Victor G Shylko
- Department of Sporting Health Tourism, Physiology, and Medicine, National Research Tomsk State University Tomsk, Russia
| | - Sergey V Popov
- Federal State Budgetary Scientific Institution "Research Institute for Cardiology," Tomsk, Russia
| | - Yana Anfinogenova
- Institute of Physics and Technology, National Research Tomsk Polytechnic University Tomsk, Russia ; Federal State Budgetary Scientific Institution "Research Institute for Cardiology," Tomsk, Russia
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163
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Cortese-Krott MM, Fernandez BO, Kelm M, Butler AR, Feelisch M. On the chemical biology of the nitrite/sulfide interaction. Nitric Oxide 2015; 46:14-24. [DOI: 10.1016/j.niox.2014.12.009] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/27/2014] [Accepted: 12/15/2014] [Indexed: 02/07/2023]
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164
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Rocha BS, Nunes C, Pereira C, Barbosa RM, Laranjinha J. A shortcut to wide-ranging biological actions of dietary polyphenols: modulation of the nitrate-nitrite-nitric oxide pathway in the gut. Food Funct 2015; 5:1646-52. [PMID: 24912104 DOI: 10.1039/c4fo00124a] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dietary polyphenols are complex, natural compounds with recognized health benefits. Initially attractive to the biomedical area due to their in vitro antioxidant properties, the biological implications of polyphenols are now known to be far from their acute ability to scavenge free radicals but rather to modulate redox signaling pathways. Actually, it is now recognized that dietary polyphenols are extensively metabolized in vivo and that the chemical, biophysical and biological properties of their metabolites are, in most cases, quite different from the ones of the parent molecules. Hence, the study of the metabolic, absorptive and signaling pathways of both phenolics and derivatives has become a major issue. In this paper we propose a short-cut for the systemic effects of polyphenols in connection with nitric oxide (˙NO) biology. This free radical is a ubiquitous signaling molecule with pivotal functions in vivo. It is produced through an enzymatic pathway and also through the reduction of dietary nitrate and nitrite in the human stomach. At acidic gastric pH, dietary polyphenols, in the form they are conveyed in foods and at high concentration, not only promote nitrite reduction to ˙NO but also embark in a complex network of chemical reactions to produce higher nitrogen oxides with signaling functions, namely by inducing post-translational modifications. Modified endogenous molecules, such as nitrated proteins and lipids, acquire important physiological functions. Thus, local and systemic effects of ˙NO such as modulation of vascular tone, mucus production in the gut and protection against ischemia-reperfusion injury are, in this sense, triggered by dietary polyphenols. Evidence to support the signaling and biological effects of polyphenols by modulation of the nitrate-nitrite-NO pathway will be herein provided and discussed. General actions of polyphenols encompassing absorption and metabolism in the intestine/liver are short-cut via the production of diffusible species in the stomach that have not only a local but also a general impact.
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Affiliation(s)
- Bárbara S Rocha
- Faculty of Pharmacy and Center for Neurosciences and Cell Biology, University of Coimbra, Health Sciences Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal.
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165
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Nitrate reduction to nitrite, nitric oxide and ammonia by gut bacteria under physiological conditions. PLoS One 2015; 10:e0119712. [PMID: 25803049 PMCID: PMC4372352 DOI: 10.1371/journal.pone.0119712] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 01/16/2015] [Indexed: 12/18/2022] Open
Abstract
The biological nitrogen cycle involves step-wise reduction of nitrogen oxides to ammonium salts and oxidation of ammonia back to nitrites and nitrates by plants and bacteria. Neither process has been thought to have relevance to mammalian physiology; however in recent years the salivary bacterial reduction of nitrate to nitrite has been recognized as an important metabolic conversion in humans. Several enteric bacteria have also shown the ability of catalytic reduction of nitrate to ammonia via nitrite during dissimilatory respiration; however, the importance of this pathway in bacterial species colonizing the human intestine has been little studied. We measured nitrite, nitric oxide (NO) and ammonia formation in cultures of Escherichia coli, Lactobacillus and Bifidobacterium species grown at different sodium nitrate concentrations and oxygen levels. We found that the presence of 5 mM nitrate provided a growth benefit and induced both nitrite and ammonia generation in E.coli and L.plantarum bacteria grown at oxygen concentrations compatible with the content in the gastrointestinal tract. Nitrite and ammonia accumulated in the growth medium when at least 2.5 mM nitrate was present. Time-course curves suggest that nitrate is first converted to nitrite and subsequently to ammonia. Strains of L.rhamnosus, L.acidophilus and B.longum infantis grown with nitrate produced minor changes in nitrite or ammonia levels in the cultures. However, when supplied with exogenous nitrite, NO gas was readily produced independently of added nitrate. Bacterial production of lactic acid causes medium acidification that in turn generates NO by non-enzymatic nitrite reduction. In contrast, nitrite was converted to NO by E.coli cultures even at neutral pH. We suggest that the bacterial nitrate reduction to ammonia, as well as the related NO formation in the gut, could be an important aspect of the overall mammalian nitrate/nitrite/NO metabolism and is yet another way in which the microbiome links diet and health.
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166
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Piknova B, Park JW, Swanson KM, Dey S, Noguchi CT, Schechter AN. Skeletal muscle as an endogenous nitrate reservoir. Nitric Oxide 2015; 47:10-16. [PMID: 25727730 DOI: 10.1016/j.niox.2015.02.145] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 12/11/2022]
Abstract
The nitric oxide synthase (NOS) family of enzymes form nitric oxide (NO) from arginine in the presence of oxygen. At reduced oxygen availability NO is also generated from nitrate in a two step process by bacterial and mammalian molybdopterin proteins, and also directly from nitrite by a variety of five-coordinated ferrous hemoproteins. The mammalian NO cycle also involves direct oxidation of NO to nitrite, and both NO and nitrite to nitrate by oxy-ferrous hemoproteins. The liver and blood are considered the sites of active mammalian NO metabolism and nitrite and nitrate concentrations in the liver and blood of several mammalian species, including human, have been determined. However, the large tissue mass of skeletal muscle had not been generally considered in the analysis of the NO cycle, in spite of its long-known presence of significant levels of active neuronal NOS (nNOS or NOS1). We hypothesized that skeletal muscle participates in the NO cycle and, due to its NO oxidizing heme protein, oxymyoglobin has high concentrations of nitrate ions. We measured nitrite and nitrate concentrations in rat and mouse leg skeletal muscle and found unusually high concentrations of nitrate but similar levels of nitrite, when compared to the liver. The nitrate reservoir in muscle is easily accessible via the bloodstream and therefore nitrate is available for transport to internal organs where it can be reduced to nitrite and NO. Nitrate levels in skeletal muscle and blood in nNOS(-/-) mice were dramatically lower when compared with controls, which support further our hypothesis. Although the nitrate reductase activity of xanthine oxidoreductase in muscle is less than that of liver, the residual activity in muscle could be very important in view of its total mass and the high basal level of nitrate. We suggest that skeletal muscle participates in overall NO metabolism, serving as a nitrate reservoir, for direct formation of nitrite and NO, and for determining levels of nitrate in other organs.
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Affiliation(s)
- Barbora Piknova
- Molecular Medicine Branch, NIDDK, NIH, Bethesda, MD 20892, USA.
| | - Ji Won Park
- Molecular Medicine Branch, NIDDK, NIH, Bethesda, MD 20892, USA
| | | | - Soumyadeep Dey
- Molecular Medicine Branch, NIDDK, NIH, Bethesda, MD 20892, USA
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167
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Abstract
SIGNIFICANCE Although oxygen (O2)-sensing cells and tissues have been known for decades, the identity of the O2-sensing mechanism has remained elusive. Evidence is accumulating that O2-dependent metabolism of hydrogen sulfide (H2S) is this enigmatic O2 sensor. RECENT ADVANCES The elucidation of biochemical pathways involved in H2S synthesis and metabolism have shown that reciprocal H2S/O2 interactions have been inexorably linked throughout eukaryotic evolution; there are multiple foci by which O2 controls H2S inactivation, and the effects of H2S on downstream signaling events are consistent with those activated by hypoxia. H2S-mediated O2 sensing has been demonstrated in a variety of O2-sensing tissues in vertebrate cardiovascular and respiratory systems, including smooth muscle in systemic and respiratory blood vessels and airways, carotid body, adrenal medulla, and other peripheral as well as central chemoreceptors. CRITICAL ISSUES Information is now needed on the intracellular location and stoichometry of these signaling processes and how and which downstream effectors are activated by H2S and its metabolites. FUTURE DIRECTIONS Development of specific inhibitors of H2S metabolism and effector activation as well as cellular organelle-targeted compounds that release H2S in a time- or environmentally controlled way will not only enhance our understanding of this signaling process but also provide direction for future therapeutic applications.
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Affiliation(s)
- Kenneth R Olson
- Department of Physiology, Indiana University School of Medicine-South Bend , South Bend, India na
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168
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Roberts LD, Ashmore T, Kotwica AO, Murfitt SA, Fernandez BO, Feelisch M, Murray AJ, Griffin JL. Inorganic nitrate promotes the browning of white adipose tissue through the nitrate-nitrite-nitric oxide pathway. Diabetes 2015; 64:471-484. [PMID: 25249574 PMCID: PMC4351918 DOI: 10.2337/db14-0496] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Inorganic nitrate was once considered an oxidation end product of nitric oxide metabolism with little biological activity. However, recent studies have demonstrated that dietary nitrate can modulate mitochondrial function in man and is effective in reversing features of the metabolic syndrome in mice. Using a combined histological, metabolomics, and transcriptional and protein analysis approach, we mechanistically defined that nitrate not only increases the expression of thermogenic genes in brown adipose tissue but also induces the expression of brown adipocyte-specific genes and proteins in white adipose tissue, substantially increasing oxygen consumption and fatty acid β-oxidation in adipocytes. Nitrate induces these phenotypic changes through a mechanism distinct from known physiological small molecule activators of browning, the recently identified nitrate-nitrite-nitric oxide pathway. The nitrate-induced browning effect was enhanced in hypoxia, a serious comorbidity affecting white adipose tissue in obese individuals, and corrected impaired brown adipocyte-specific gene expression in white adipose tissue in a murine model of obesity. Because resulting beige/brite cells exhibit antiobesity and antidiabetic effects, nitrate may be an effective means of inducing the browning response in adipose tissue to treat the metabolic syndrome.
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MESH Headings
- Adipocytes, Brown/physiology
- Adipocytes, White/drug effects
- Adipocytes, White/physiology
- Adipose Tissue, Brown
- Adipose Tissue, White/drug effects
- Adipose Tissue, White/metabolism
- Animals
- Cells, Cultured
- Cyclic GMP
- Cyclic GMP-Dependent Protein Kinases
- Dose-Response Relationship, Drug
- Male
- Mice
- Mice, Inbred C57BL
- Nitrates/metabolism
- Nitrates/pharmacology
- Nitric Oxide/metabolism
- Nitrites/metabolism
- Rats
- Rats, Wistar
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Affiliation(s)
- Lee D Roberts
- Medical Research Council – Human Nutrition Research, Elsie Widdowson Laboratory, 120 Fulbourn Road, Cambridge, CB2 9NL, UK
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke’s Site, Cambridge, CB2 1GA, UK
| | - Tom Ashmore
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke’s Site, Cambridge, CB2 1GA, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | - Aleksandra O Kotwica
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | - Steven A Murfitt
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke’s Site, Cambridge, CB2 1GA, UK
| | - Bernadette O Fernandez
- Faculty of Medicine, Clinical & Experimental Sciences, University of Southampton, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Martin Feelisch
- Faculty of Medicine, Clinical & Experimental Sciences, University of Southampton, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | - Julian L Griffin
- Medical Research Council – Human Nutrition Research, Elsie Widdowson Laboratory, 120 Fulbourn Road, Cambridge, CB2 9NL, UK
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, 80 Tennis Court Road, Old Addenbrooke’s Site, Cambridge, CB2 1GA, UK
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169
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Omar SA, Fok H, Tilgner KD, Nair A, Hunt J, Jiang B, Taylor P, Chowienczyk P, Webb AJ. Paradoxical normoxia-dependent selective actions of inorganic nitrite in human muscular conduit arteries and related selective actions on central blood pressures. Circulation 2015; 131:381-9; discussion 389. [PMID: 25533964 DOI: 10.1161/circulationaha.114.009554] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Inorganic nitrite dilates small resistance arterioles via hypoxia-facilitated reduction to vasodilating nitric oxide. The effects of nitrite in human conduit arteries have not been investigated. In contrast to nitrite, organic nitrates are established selective dilators of conduit arteries. METHODS AND RESULTS We examined the effects of local and systemic administration of sodium nitrite on the radial artery (a muscular conduit artery), forearm resistance vessels (forearm blood flow), and systemic hemodynamics in healthy male volunteers (n=43). Intrabrachial sodium nitrite (8.7 μmol/min) increased radial artery diameter by a median of 28.0% (25th and 75th percentiles, 25.7% and 40.1%; P<0.001). Nitrite (0.087-87 μmol/min) displayed conduit artery selectivity similar to that of glyceryl trinitrate (0.013-4.4 nmol/min) over resistance arterioles. Nitrite dose-dependently increased local cGMP production at the dose of 2.6 μmol/min by 1.1 pmol·min(-1)·100 mL(-1) tissue (95% confidence interval, 0.5-1.8). Nitrite-induced radial artery dilation was enhanced by administration of acetazolamide (oral or intra-arterial) and oral raloxifene (P=0.0248, P<0.0001, and P=0.0006, respectively) but was inhibited under hypoxia (P<0.0001) and hyperoxia (P=0.0006) compared with normoxia. Systemic intravenous administration of sodium nitrite (8.7 μmol/min) dilated the radial artery by 10.7% (95% confidence interval, 6.8-14.7) and reduced central systolic blood pressure by 11.6 mm Hg (95% confidence interval, 2.4-20.7), augmentation index, and pulse wave velocity without changing peripheral blood pressure. CONCLUSIONS Nitrite selectively dilates conduit arteries at supraphysiological and near-physiological concentrations via a normoxia-dependent mechanism that is associated with cGMP production and is enhanced by acetazolamide and raloxifene. The selective central blood pressure-lowering effects of nitrite have therapeutic potential to reduce cardiovascular events.
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Affiliation(s)
- Sami A Omar
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Henry Fok
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Katharina D Tilgner
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Ashok Nair
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Joanne Hunt
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Benyu Jiang
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Paul Taylor
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Phil Chowienczyk
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Andrew J Webb
- From the King's College London British Heart Foundation Centre, Cardiovascular Division, Department of Clinical Pharmacology, London, UK (S.A.O., H.F., A.N., J.H., B.J., P.C., A.J.W.); Division of Women's Health, Women's Health Academic Centre, King's College London and King's Health Partners, London, UK (K.D.T., P.T.); Department of Anaesthetics (A.N.), and Biomedical Research Centre (S.A.O., H.F., A.N., J.H., B.J., P.C., A.W.), Guy's & St. Thomas' NHS Foundation Trust, London, UK.
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170
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Kharitonova M, Iezhitsa I, Zheltova A, Ozerov A, Spasov A, Skalny A. Comparative angioprotective effects of magnesium compounds. J Trace Elem Med Biol 2015; 29:227-34. [PMID: 25127069 DOI: 10.1016/j.jtemb.2014.06.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 06/30/2014] [Accepted: 06/30/2014] [Indexed: 01/10/2023]
Abstract
Magnesium (Mg) deficiency is implicated in the development of numerous disorders of the cardiovascular system. Moreover, the data regarding the efficacy of different magnesium compounds in the correction of impaired functions due to low magnesium intake are often fragmentary and inconsistent. The aim of this study was to compare the effects of the most bioavailable Mg compounds (Mg l-aspartate, Mg N-acetyltaurate, Mg chloride, Mg sulphate and Mg oxybutyrate) on systemic inflammation and endothelial dysfunction in rats fed a low Mg diet for 74 days. A low Mg diet decreased the Mg concentration in the plasma and erythrocytes, which was accompanied by a reduced concentration of eNOs and increased levels of endothelin-1 level in the serum and impaired endothelium-dependent vasodilatation. These effects increased the concentration of proinflammatory molecules, such as VCAM-1, TNF-α, IL-6 and CRP, indicating the development of systemic inflammation and endothelial dysfunction. The increased total NO level, which estimated from the sum of the nitrate and nitrite concentrations in the serum, may also be considered to be a proinflammatory marker. Two weeks of Mg supplementation partially or fully normalised the ability of the vascular wall to effect adequate endothelium-dependent vasodilatation and reversed the levels of most endothelial dysfunction and inflammatory markers (except CRP) to the mean values of the control group. Mg sulphate had the smallest effect on the endothelin-1, TNF-α and VCAM-1 levels. Mg N-acetyltaurate was significantly more effective in restoring the level of eNOS compared to all other studied compounds, except for Mg oxybutyrate. Taken together, the present findings demonstrate that all Mg compounds equally alleviate endothelial dysfunction and inflammation caused by Mg deficiency. Mg sulphate tended to be the least effective compound.
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Affiliation(s)
- Maria Kharitonova
- Department of Pharmacology, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia; Institute of Pharmacy, Department of Pharmacology and Toxicology, University of Innsbruck, Center for Chemistry and Biomedicine, Innrain 80-82/III, A-6020 Innsbruck, Austria
| | - Igor Iezhitsa
- Department of Pharmacology, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia; Universiti Teknologi MARA, Faculty of Medicine, Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor Darul Ehsan, Malaysia; Universiti Teknologi MARA (UiTM), RIG "Molecular Pharmacology and Advanced Therapeutics", Brain and Neuroscience Communities of Research, 40450 Shah Alam, Selangor Darul Ehsan, Malaysia.
| | - Anastasia Zheltova
- Department of Pharmacology, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia; Department of Allergology and Immunology, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia
| | - Alexander Ozerov
- Department for Pharmaceutical and Toxicological Chemistry, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia
| | - Alexander Spasov
- Department of Pharmacology, Volgograd State Medical University, Pl. Pavshih Bortsov, 1, Volgograd 400131, Russia
| | - Anatoly Skalny
- Russian Society of Trace Elements in Medicine, 46 Zemlyanoy Val str., Moscow 105064, Russia; Trace Element - Institute for UNESCO, 7 rue Guillaume Paradin, 69008 Lyon, France
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171
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Kuzenkov VS, Krushynsky AL. [A protective role of the nitrite/nitrate reductase system in ischemic stroke]. Zh Nevrol Psikhiatr Im S S Korsakova 2015; 115:58-66. [PMID: 26978642 DOI: 10.17116/jnevro201511512258-66] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To reveal a protective role of the nitrite/nitrate reductase system in NO- synthase (NOS) inhibition in ischemic stroke. MATERIAL AND METHODS An effect of the non-selective NOS inhibitor Nω-nitro-L-arginine (L-NNA) introduced in dose of 25 mg/kg and nitrates (КNO3, NaNO3, Mg(NO3)2, Ca(NO3) in doses of 5 mg/kg) on ischemic stroke induced by the occlusion of carotid arteries in an experimental model was studied. The animals (Wistar rats) were stratified into 20 experimental groups (n=480) and 4 control groups (n=96). One of nitrates or L-NNA along with one of nitrates or L-NNA alone were administered to experimental groups 1h before brain ischemia or 5s after carotid artery occlusion. 0.9% NaCl was used in the control rats. RESULTS L-NNA increases neurological deficit and lethality in brain ischemia. Depending on a cation, the nitrite/nitrate reductase system may play a protective role in the inhibition of NOS-system in brain ischemia. CONCLUSION In brain ischemia and NOS inhibition, Mg(NO3)2 has the greatest protective effect.
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172
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The evolution of nitric oxide signalling in vertebrate blood vessels. J Comp Physiol B 2014; 185:153-71. [DOI: 10.1007/s00360-014-0877-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 11/06/2014] [Accepted: 11/11/2014] [Indexed: 10/24/2022]
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173
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Kuleva NV, Krasovskaya IE, Shumilova TE. The influence of small doses of exogenic nitrite on oxidative modifications of water-soluble proteins of rat cardiac and skeletal muscle. Biophysics (Nagoya-shi) 2014. [DOI: 10.1134/s0006350914050121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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174
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Uusijärvi J, Eriksson K, Larsson AC, Nihlén C, Schiffer T, Lindholm P, Weitzberg E. Effects of hyperbaric oxygen on nitric oxide generation in humans. Nitric Oxide 2014; 44:88-97. [PMID: 25498903 DOI: 10.1016/j.niox.2014.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/12/2014] [Accepted: 12/07/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND Hyperbaric oxygen (HBO2) has been suggested to affect nitric oxide (NO) generation in humans. Specific NO synthases (NOSs) use L-arginine and molecular oxygen to produce NO but this signaling radical may also be formed by serial reduction of the inorganic anions nitrate and nitrite. Interestingly, commensal facultative anaerobic bacteria in the oral cavity are necessary for the first step to reduce nitrate to nitrite. The nitrate-nitrite-NO pathway is greatly potentiated by hypoxia and low pH in contrast to classical NOS-dependent NO generation. We investigated the effects of HBO2 on NO generation in healthy subjects including orally and nasally exhaled NO, plasma and salivary nitrate and nitrite as well as plasma cGMP and plasma citrulline/arginine ratio. In addition, we also conducted in-vitro experiments in order to investigate the effects of hyperoxia on nitrate/nitrite metabolism and NO generation by oral bacteria. METHODS Two separate HBO2 experiments were performed. In a cross-over experiment (EXP1) subjects breathed air at 130 kPa (control) or oxygen at 250 kPa for 100 minutes and parameters were measured before and after exposure. In experiment 2 (EXP 2) measurements were performed also during HBO2 at 250 kPa for 110 minutes. RESULTS HBO2 acutely reduced orally and nasally exhaled NO by 30% and 16%, respectively. There was a marked decrease in salivary nitrite/nitrate ratio during and after HBO2, indicating a reduced bacterial conversion of nitrate to nitrite and NO. This was supported by in vitro experiments with oral bacteria showing that hyperoxia inhibited bacterial nitrate and nitrite reduction leading to reduced NO generation. Plasma nitrate was unaffected by HBO2 while plasma nitrite was reduced during HBO2 treatment. In contrast, plasma cGMP increased during HBO2 as did citrulline/arginine ratio after treatment and control. CONCLUSION HBO2-exposure in humans affects NO generation in the airways and systemically differently. These data suggest that the individual NOSs as well as the nitrate-nitrite-NO pathway do not respond in a similar way to HBO2.
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Affiliation(s)
- Johan Uusijärvi
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Deparment of Anesthesia & Intensive Care, Karolinska University Hospital, Stockholm, Sweden
| | - Karin Eriksson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Deparment of Anesthesia & Intensive Care, Karolinska University Hospital, Stockholm, Sweden
| | - Agneta C Larsson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Carina Nihlén
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Tomas Schiffer
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Peter Lindholm
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Department of Radiology, Karolinska University Hospital, Stockholm, Sweden
| | - Eddie Weitzberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; Deparment of Anesthesia & Intensive Care, Karolinska University Hospital, Stockholm, Sweden.
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175
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Casey DP, Treichler DP, Ganger CT, Schneider AC, Ueda K. Acute dietary nitrate supplementation enhances compensatory vasodilation during hypoxic exercise in older adults. J Appl Physiol (1985) 2014; 118:178-86. [PMID: 25414241 DOI: 10.1152/japplphysiol.00662.2014] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
We have previously demonstrated that aging reduces the compensatory vasodilator response during hypoxic exercise due to blunted nitric oxide (NO) signaling. Recent evidence suggests that NO bioavailability can be augmented by dietary nitrate through the nitrate-nitrite pathway. Thus we tested the hypothesis that acute dietary nitrate supplementation increases the compensatory vasodilator response to hypoxic exercise, particularly in older adults. Thirteen young (25 ± 1 yr) and 12 older (64 ± 2 yr) adults performed rhythmic forearm exercise at 20% of maximum voluntary contraction during normoxia and hypoxia (∼80% O2 saturation); both before (control) and 3 h after beetroot juice (BR) consumption. Forearm vascular conductance (FVC; ml·min(-1)·100 mmHg(-1)) was calculated from forearm blood flow (ml/min) and blood pressure (mmHg). Compensatory vasodilation was defined as the relative increase in FVC due to hypoxic exercise (i.e., % increase compared with respective normoxic exercise trial). Plasma nitrite was determined from venous blood samples obtained before the control trials and each of the exercise trials (normoxia and hypoxia) after BR. Consumption of BR increased plasma nitrite in both young and older adults (P < 0.001). During the control condition, the compensatory vasodilator response to hypoxic exercise was attenuated in older compared with young adults (3.8 ± 1.7% vs. 14.2 ± 1.2%, P < 0.001). Following BR consumption, compensatory vasodilation did not change in young (13.7 ± 3.3%, P = 0.81) adults but was substantially augmented in older adults (11.4 ± 2.1%, P < 0.01). Our data suggest that acute dietary nitrate supplementation increases the compensatory vasodilator response to hypoxic exercise in older but not young adults.
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Affiliation(s)
- Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - David P Treichler
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Charles T Ganger
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Aaron C Schneider
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and
| | - Kenichi Ueda
- Department of Anesthesia, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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176
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Garry PS, Ezra M, Rowland MJ, Westbrook J, Pattinson KTS. The role of the nitric oxide pathway in brain injury and its treatment--from bench to bedside. Exp Neurol 2014; 263:235-43. [PMID: 25447937 DOI: 10.1016/j.expneurol.2014.10.017] [Citation(s) in RCA: 251] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 10/09/2014] [Accepted: 10/22/2014] [Indexed: 10/24/2022]
Abstract
Nitric oxide (NO) is a key signalling molecule in the regulation of cerebral blood flow. This review summarises current evidence regarding the role of NO in the regulation of cerebral blood flow at rest, under physiological conditions, and after brain injury, focusing on subarachnoid haemorrhage, traumatic brain injury, and ischaemic stroke and following cardiac arrest. We also review the role of NO in the response to hypoxic insult in the developing brain. NO depletion in ischaemic brain tissue plays a pivotal role in the development of subsequent morbidity and mortality through microcirculatory disturbance and disordered blood flow regulation. NO derived from endothelial nitric oxide synthase (eNOS) appears to have neuroprotective properties. However NO derived from inducible nitric oxide synthase (iNOS) may have neurotoxic effects. Cerebral NO donor agents, for example sodium nitrite, appear to replicate the effects of eNOS derived NO, and therefore have neuroprotective properties. This is true in both the adult and immature brain. We conclude that these agents should be further investigated as targeted pharmacotherapy to protect against secondary brain injury.
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Affiliation(s)
- P S Garry
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.
| | - M Ezra
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - M J Rowland
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - J Westbrook
- Neurosciences Intensive Care Unit, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - K T S Pattinson
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
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177
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Kuzenkov VS, Krushinskii AL. Protective Effect of Magnesium Nitrate against Neurological Disorders Provoked by Cerebral Ischemia in Rats. Bull Exp Biol Med 2014; 157:721-3. [DOI: 10.1007/s10517-014-2651-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Indexed: 10/24/2022]
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178
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Habermeyer M, Roth A, Guth S, Diel P, Engel KH, Epe B, Fürst P, Heinz V, Humpf HU, Joost HG, Knorr D, de Kok T, Kulling S, Lampen A, Marko D, Rechkemmer G, Rietjens I, Stadler RH, Vieths S, Vogel R, Steinberg P, Eisenbrand G. Nitrate and nitrite in the diet: how to assess their benefit and risk for human health. Mol Nutr Food Res 2014; 59:106-28. [PMID: 25164923 DOI: 10.1002/mnfr.201400286] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/29/2014] [Accepted: 08/04/2014] [Indexed: 12/15/2022]
Abstract
Nitrate is a natural constituent of the human diet and an approved food additive. It can be partially converted to nitrogen monoxide, which induces vasodilation and thereby decreases blood pressure. This effect is associated with a reduced risk regarding cardiovascular disease, myocardial infarction, and stroke. Moreover, dietary nitrate has been associated with beneficial effects in patients with gastric ulcer, renal failure, or metabolic syndrome. Recent studies indicate that such beneficial health effects due to dietary nitrate may be achievable at intake levels resulting from the daily consumption of nitrate-rich vegetables. N-nitroso compounds are endogenously formed in humans. However, their relevance for human health has not been adequately explored up to now. Nitrate and nitrite are per se not carcinogenic, but under conditions that result in endogenous nitrosation, it cannot be excluded that ingested nitrate and nitrite may lead to an increased cancer risk and may probably be carcinogenic to humans. In this review, the known beneficial and detrimental health effects related to dietary nitrate/nitrite intake are described and the identified gaps in knowledge as well as the research needs required to perform a reliable benefit/risk assessment in terms of long-term human health consequences due to dietary nitrate/nitrite intake are presented.
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Affiliation(s)
- Michael Habermeyer
- Department of Food Chemistry and Toxicology, University of Kaiserslautern, Kaiserslautern, Germany**
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179
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Computational analysis of nitric oxide biotransport to red blood cell in the presence of free hemoglobin and NO donor. Microvasc Res 2014; 95:15-25. [DOI: 10.1016/j.mvr.2014.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 05/16/2014] [Accepted: 06/09/2014] [Indexed: 02/06/2023]
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180
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Rassaf T, Ferdinandy P, Schulz R. Nitrite in organ protection. Br J Pharmacol 2014; 171:1-11. [PMID: 23826831 DOI: 10.1111/bph.12291] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 06/09/2013] [Accepted: 06/21/2013] [Indexed: 12/15/2022] Open
Abstract
In the last decade, the nitrate-nitrite-nitric oxide pathway has emerged to therapeutical importance. Modulation of endogenous nitrate and nitrite levels with the subsequent S-nitros(yl)ation of the downstream signalling cascade open the way for novel cytoprotective strategies. In the following, we summarize the actual literature and give a short overview on the potential of nitrite in organ protection.
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Affiliation(s)
- Tienush Rassaf
- Department of Medicine, Division of Cardiology, Pulmonary and Vascular Medicine, University Hospital Düsseldorf, Düsseldorf, Germany
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181
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Sanders BC, Hassan SM, Harrop TC. NO2– Activation and Reduction to NO by a Nonheme Fe(NO2)2 Complex. J Am Chem Soc 2014; 136:10230-3. [DOI: 10.1021/ja505236x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Brian C. Sanders
- Department
of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, Athens, Georgia 30602, United States
| | - Sayed M. Hassan
- College
of Agricultural and Environmental Sciences, The University of Georgia, Athens, Georgia 30605, United States
| | - Todd C. Harrop
- Department
of Chemistry and Center for Metalloenzyme Studies, The University of Georgia, Athens, Georgia 30602, United States
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182
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Inflammation, vasospasm, and brain injury after subarachnoid hemorrhage. BIOMED RESEARCH INTERNATIONAL 2014; 2014:384342. [PMID: 25105123 PMCID: PMC4106062 DOI: 10.1155/2014/384342] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 05/14/2014] [Accepted: 05/26/2014] [Indexed: 12/15/2022]
Abstract
Subarachnoid hemorrhage (SAH) can lead to devastating neurological outcomes, and there are few pharmacologic treatments available for treating this condition. Both animal and human studies provide evidence of inflammation being a driving force behind the pathology of SAH, leading to both direct brain injury and vasospasm, which in turn leads to ischemic brain injury. Several inflammatory mediators that are elevated after SAH have been studied in detail. While there is promising data indicating that blocking these factors might benefit patients after SAH, there has been little success in clinical trials. One of the key factors that complicates clinical trials of SAH is the variability of the initial injury and subsequent inflammatory response. It is likely that both genetic and environmental factors contribute to the variability of patients' post-SAH inflammatory response and that this confounds trials of anti-inflammatory therapies. Additionally, systemic inflammation from other conditions that affect patients with SAH could contribute to brain injury and vasospasm after SAH. Continuing work on biomarkers of inflammation after SAH may lead to development of patient-specific anti-inflammatory therapies to improve outcome after SAH.
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183
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Meamarbashi A, Alipour M. Moderate dose of watercress and red radish does not reduce oxygen consumption during graded exhaustive exercise. AVICENNA JOURNAL OF PHYTOMEDICINE 2014; 4:267-72. [PMID: 25068141 PMCID: PMC4110783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/20/2014] [Accepted: 03/11/2014] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Very recent studies have reported positive effects of dietary nitrate on the oxygen consumption during exercise. This research aimed to study the effect of moderate dose of high-nitrate vegetables, watercress (Nasturtium officinale) and red radish (Raphanus sativus) compared with a control group on the incremental treadmill exercise test following a standard Bruce protocol controlled by computer. MATERIALS AND METHODS Group 1 consumed 100 g watercress (n=11, 109.5 mg nitrate/day), and group 2 consumed 100 g red radish (n=11, mg 173.2 mg nitrate/day) for seven days, and control group (n=14) was prohibited from high nitrate intake. RESULTS During exercise, watercress group showed significant changes in the maximum values of Respiratory Exchange Ratio (RER) (p<0.05), End-Tidal O2 Fraction (FETO2) (p<0.05), and energy consumption from carbohydrate (p<0.01). Red radish group had a significant increase in the VCO2 (p<0.01), RER (p<0.01), VT (p<0.05), VCO2/kg (p<0.05), and energy consumption from carbohydrates (p<0.01). When all groups in the same workload were normalized by the subject's body mass, watercress had a significant increase in the total expired CO2 (p<0.05), RER (p<0.05), FETO2 (p<0.05), and energy consumption from carbohydrates (p<0.05) compared with the control group. Similar comparison between red radish and control group revealed a significant increase during pre-test in the total CO2 production (p<0.05), VCO2 (p<0.05), RER (p<0.01), VT (p<0.05), and VCO2/kg (p<0.05). Conclusion : Current results indicate higher carbon dioxide production in the experimental groups in the same workload. This might have a negative impact on the exercise performance. Further investigations with controlled exercise program will be necessary.
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Affiliation(s)
- Abbas Meamarbashi
- Department of Physical Education and Sports Sciences, University of Mohaghegh Ardabili, Ardabil, I. R. Iran
| | - Meysam Alipour
- Department of Physical Education and Sports Sciences, University of Mohaghegh Ardabili, Ardabil, I. R. Iran
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184
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Bailey JC, Feelisch M, Horowitz JD, Frenneaux MP, Madhani M. Pharmacology and therapeutic role of inorganic nitrite and nitrate in vasodilatation. Pharmacol Ther 2014; 144:303-20. [PMID: 24992304 DOI: 10.1016/j.pharmthera.2014.06.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 06/25/2014] [Indexed: 02/07/2023]
Abstract
Nitrite has emerged as an important bioactive molecule that can be biotransformed to nitric oxide (NO) related metabolites in normoxia and reduced to NO under hypoxic and acidic conditions to exert vasodilatory effects and confer a variety of other benefits to the cardiovascular system. Abundant research is currently underway to understand the mechanisms involved and define the role of nitrite in health and disease. In this review we discuss the impact of nitrite and dietary nitrate on vascular function and the potential therapeutic role of nitrite in acute heart failure.
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Affiliation(s)
- J C Bailey
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - M Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - J D Horowitz
- The Queen Elizabeth Hospital, Adelaide, Australia
| | - M P Frenneaux
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, UK
| | - M Madhani
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK.
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185
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Hypoxic potentiation of nitrite effects in human vessels and platelets. Nitric Oxide 2014; 40:36-44. [PMID: 24858215 DOI: 10.1016/j.niox.2014.05.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 05/13/2014] [Accepted: 05/15/2014] [Indexed: 11/22/2022]
Abstract
Previous studies in non-human blood vessels and in platelets have demonstrated that under hypoxic conditions release of NO from nitrite (NO2(-)) is potentiated by deoxyhaemoglobin. In the current study, we characterized hypoxic potentiation of NO2(-) effects in human vasculature and platelets in vitro, addressing underlying mechanisms. The vasodilator efficacy of NO2(-), in comparison with glyceryl trinitrate (GTN), was evaluated in vitro, using segments of human saphenous vein. Under hypoxic conditions, there was a leftward shift of the NO2(-) concentration-response curve (EC50: 22 μM in hyperoxia vs 3.5 μM in hypoxia; p<0.01), but no significant potentiation of GTN effect. In the presence of red blood cells, hypoxic potentiation of NO2(-) vasodilator effect was accentuated. In whole blood samples and platelet-rich plasma (PRP) we assessed inhibition of platelet aggregation by NO2(-) (1mM), in comparison with that of sodium nitroprusside (SNP, 10 μM). In individual subjects (n=37), there was a strong correlation (r=0.75, p<0.0001) between anti-aggregatory effects of NO2(-) and SNP in whole blood, signifying that resultant sGC activation underlies biological effect and responses to NO2(-) are diminished in the presence of NO resistance. In PRP, the effects of NO2(-) were less pronounced than in whole blood (p=0.0001), suggesting an important role of Hb (within RBCs) in the bioconversion of NO2(-) to NO. Inhibition of platelet aggregation by NO2(-) was almost 3-fold greater in venous than in arterial blood (p<0.0001), and deoxyHb concentration directly correlated (r=0.69, p=0.013) with anti-aggregatory response. Incremental hypoxia applied to venous blood samples (in hypoxic chamber) caused a progressive increase in both deoxyHb level and anti-aggregatory effect of NO2(-). When subjects inhaled a 12% O2 mixture for 20 min, there was a 3-fold rise in blood deoxyHb fraction (p<0.01). In PRP, response to NO2(-) also increased under hypoxia, and was further enhanced (p<0.01) by deoxyHb. Furthermore, deoxyHb exerted significant anti-aggregatory effects even in the absence of added NO2(-), suggesting a role for endogenous NO2(-). The results of this work provide further mechanistic insights into hypoxic potentiation of vasodilator and anti-aggregatory actions of NO2(-). In human saphenous veins and blood, the balance of evidence suggests differential rates of NO release from NO2(-) (largely modulated by deoxyHb) as the fundamental mechanism.
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186
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Tong J, Zweier JR, Huskey RL, Ismail RS, Hemann C, Zweier JL, Liu X. Effect of temperature, pH and heme ligands on the reduction of Cygb(Fe(3+)) by ascorbate. Arch Biochem Biophys 2014; 554:1-5. [PMID: 24780244 DOI: 10.1016/j.abb.2014.04.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/14/2014] [Accepted: 04/21/2014] [Indexed: 01/08/2023]
Abstract
Cytoglobin (Cygb) plays a role in regulating vasodilation in response to changes in local oxygen concentration by altering the rate of nitric oxide (NO) metabolism. Because the reduction of Cygb(Fe(3+)) by a reductant is the control step for Cygb-mediated NO metabolism, we examined the effects of temperature, pH, and heme ligands on the Cygb(Fe(3+)) reduction by ascorbate (Asc) under anaerobic conditions. The standard enthalpy of Cygb(Fe(3+)) reduction by Asc was determined to be 42.4 ± 3.1 kJ/mol. The rate of Cygb(Fe(3+)) reduction increased ~6% per °C when temperature varied from 35°C to 40°C. The yield and the rate of Cygb(Fe(3+)) reduction significantly increases with pH (2-3 times per pH unit), paralleling the formation of the Asc ion (A(2-)) and the increased stability of reduced state of heme iron at high pH values. Heme ligand cyanide (CN(-)) decreased the yield and the rate of Cygb(Fe(3+)) reduction, but ligands CO and NO allowed the process of Cygb(Fe(3+)) reduction to continue to completion. Critical information is provided for modeling and prediction of the process of Cygb-mediated NO metabolism in vessels in a range of temperature and pH values.
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Affiliation(s)
- Jianjing Tong
- Emergency Department, Shanghai Ruijin Hospital, Shanghai Jiaotong University School of Medicine, 197 Ruijin Er Road, Shanghai 200025, China; Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Joseph R Zweier
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Rachael L Huskey
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Raed S Ismail
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Craig Hemann
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Jay L Zweier
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, OH, USA.
| | - Xiaoping Liu
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, USA; Department of Internal Medicine, The Ohio State University College of Medicine, Columbus, OH, USA.
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187
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Affiliation(s)
- Luisa B. Maia
- REQUIMTE/CQFB, Departamento
de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - José J. G. Moura
- REQUIMTE/CQFB, Departamento
de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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188
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Clinical evidence demonstrating the utility of inorganic nitrate in cardiovascular health. Nitric Oxide 2014; 38:45-57. [PMID: 24650698 DOI: 10.1016/j.niox.2014.03.162] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 03/04/2014] [Accepted: 03/09/2014] [Indexed: 02/03/2023]
Abstract
The discovery of nitric oxide and its role in almost every facet of human biology opened a new avenue for treatment through manipulation of its canonical signaling and by attempts to augment endogenous nitric oxide generation through provision of substrate and co-factors to the endothelial nitric oxide synthase complex. This has been particularly so in the cardiovascular system and it is well recognized that there is reduced bioavailable nitric oxide in patients with both cardiovascular risk factors and manifest vascular disease. However, these attempts have failed to deliver the expected benefits of such an approach. Recently, an alternative pathway for nitric oxide synthesis has been elucidated that can produce authentic nitric oxide from the 1 electron reduction of inorganic nitrite. Furthermore, it has long been known that symbiotic, facultative, oral microflora can facilitate the reduction of inorganic nitrate, that is ingested in the average diet in millimolar amounts, to inorganic nitrite itself. Thus, there exists an alternative reductive pathway from nitrate, via nitrite as an intermediate, to nitric oxide that provides a novel pathway that may be amenable to therapeutic manipulation. As such, various research groups have explored the utility of manipulation of this nitrate-nitrite-nitric oxide pathway in situations in which nitric oxide is known to have a prominent role. Animal and early-phase human studies of both inorganic nitrite and nitrate supplementation have shown beneficial effects in blood pressure control, platelet function, vascular health and exercise capacity. This review considers in detail the pathways of inorganic nitrate bioactivation and the evidence of clinical utility to date on the cardiovascular system.
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189
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Bekeschus S, Kolata J, Winterbourn C, Kramer A, Turner R, Weltmann KD, Bröker B, Masur K. Hydrogen peroxide: A central player in physical plasma-induced oxidative stress in human blood cells. Free Radic Res 2014; 48:542-9. [DOI: 10.3109/10715762.2014.892937] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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190
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Nitric oxide generation from heme/copper assembly mediated nitrite reductase activity. J Biol Inorg Chem 2014; 19:515-28. [PMID: 24430198 DOI: 10.1007/s00775-013-1081-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/18/2013] [Indexed: 01/03/2023]
Abstract
Nitric oxide (NO) as a cellular signaling molecule and vasodilator regulates a range of physiological and pathological processes. Nitrite (NO2 (-)) is recycled in vivo to generate nitric oxide, particularly in physiologic hypoxia and ischemia. The cytochrome c oxidase binuclear heme a 3/CuB active site is one entity known to be responsible for conversion of cellular nitrite to nitric oxide. We recently reported that a partially reduced heme/copper assembly reduces nitrite ion, producing nitric oxide; the heme serves as the reductant and the cupric ion provides a Lewis acid interaction with nitrite, facilitating nitrite (N-O) bond cleavage (Hematian et al., J. Am. Chem. Soc. 134:18912-18915, 2012). To further investigate this nitrite reductase chemistry, copper(II)-nitrito complexes with tridentate and tetradentate ligands were used in this study, where either O,O'-bidentate or O-unidentate modes of nitrite binding to the cupric center are present. To study the role of the reducing ability of the ferrous heme center, two different tetraarylporphyrinate-iron(II) complexes, one with electron-donating para-methoxy peripheral substituents and the other with electron-withdrawing 2,6-difluorophenyl substituents, were used. The results show that differing modes of nitrite coordination to the copper(II) ion lead to differing kinetic behavior. Here, also, the ferrous heme is in all cases the source of the reducing equivalent required to convert nitrite to nitric oxide, but the reduction ability of the heme center does not play a key role in the observed overall reaction rate. On the basis of our observations, reaction mechanisms are proposed and discussed in terms of heme/copper heterobinuclear structures.
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191
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Cortese-Krott MM, Kelm M. Endothelial nitric oxide synthase in red blood cells: key to a new erythrocrine function? Redox Biol 2014; 2:251-8. [PMID: 24494200 PMCID: PMC3909820 DOI: 10.1016/j.redox.2013.12.027] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 12/21/2013] [Indexed: 02/06/2023] Open
Abstract
Red blood cells (RBC) have been considered almost exclusively as a transporter of metabolic gases and nutrients for the tissues. It is an accepted dogma that RBCs take up and inactivate endothelium-derived NO via rapid reaction with oxyhemoglobin to form methemoglobin and nitrate, thereby limiting NO available for vasodilatation. Yet it has also been shown that RBCs not only act as "NO sinks", but exert an erythrocrine function - i.e an endocrine function of RBC - by synthesizing, transporting and releasing NO metabolic products and ATP, thereby potentially controlling systemic NO bioavailability and vascular tone. Recent work from our and others laboratory demonstrated that human RBCs carry an active type 3, endothelial NO synthase (eNOS), constitutively producing NO under normoxic conditions, the activity of which is compromised in patients with coronary artery disease. In this review we aim to discuss the potential role of red cell eNOS in RBC signaling and function, and to critically revise evidence to this date showing a role of non-endothelial circulating eNOS in cardiovascular pathophysiology.
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Affiliation(s)
- Miriam M Cortese-Krott
- Cardiovascular Research Laboratory, Department of Cardiology, Pneumology and Angiology, Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
| | - Malte Kelm
- Cardiovascular Research Laboratory, Department of Cardiology, Pneumology and Angiology, Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
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192
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Cristiana F, Elena A, Nina Z. Superoxide Dismutase: Therapeutic Targets in SOD Related Pathology. Health (London) 2014. [DOI: 10.4236/health.2014.610123] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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193
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Bošković M, Grabnar I, Terzič T, Kores Plesničar B, Vovk T. Oxidative stress in schizophrenia patients treated with long-acting haloperidol decanoate. Psychiatry Res 2013; 210:761-8. [PMID: 24041751 DOI: 10.1016/j.psychres.2013.08.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 06/03/2013] [Accepted: 08/18/2013] [Indexed: 11/24/2022]
Abstract
In this study the role of oxidative stress in schizophrenia was investigated by evaluating the relationship of oxidative stress markers with neurochemistry, psychopathology, and extrapyramidal symptoms. Antioxidant activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and concentrations of malondialdehyde, protein carbonyls, nitrite, nitrate, glutathione, dopamine, noradrenaline, adrenaline, and serotonin were measured in 52 outpatients with DSM-IV diagnosis of schizophrenia treated with haloperidol decanoate. Psychopathology and extrapyramidal symptoms were assessed by positive and negative syndrome scale, global assessment of functioning, abnormal involuntary movement scale, Simpson Angus scale, and Barnes akathisia rating scale. Haloperidol dose was positively correlated with plasma protein carbonyls. Longer duration of illness was associated with decreased levels of glutathione peroxidase. Increased activity of superoxide dismutase was associated with increased levels of catalase, glutathione peroxidase, glutathione reductase and reduced glutathione, and decreased concentration of malondialdehyde, indicating joint action of various antioxidative systems. Increased levels of nitrite and noradrenaline were associated with decreased level of malondialdehyde. Akathisia was greater in patients with decreased catalase activity, indicating involvement of impaired antioxidant defense in developing extrapyramidal symptoms. These results confirm the hypothesis that oxidative stress is involved in pathophysiology of schizophrenia and severity of extrapyramidal symptoms.
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Affiliation(s)
- Marija Bošković
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
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194
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Aamand R, Dalsgaard T, Ho YCL, Møller A, Roepstorff A, Lund TE. A NO way to BOLD?: Dietary nitrate alters the hemodynamic response to visual stimulation. Neuroimage 2013; 83:397-407. [DOI: 10.1016/j.neuroimage.2013.06.069] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 06/17/2013] [Accepted: 06/25/2013] [Indexed: 02/06/2023] Open
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195
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Østergaard L, Aamand R, Karabegovic S, Tietze A, Blicher JU, Mikkelsen IK, Iversen NK, Secher N, Engedal TS, Anzabi M, Jimenez EG, Cai C, Koch KU, Naess-Schmidt ET, Obel A, Juul N, Rasmussen M, Sørensen JCH. The role of the microcirculation in delayed cerebral ischemia and chronic degenerative changes after subarachnoid hemorrhage. J Cereb Blood Flow Metab 2013; 33:1825-37. [PMID: 24064495 PMCID: PMC3851911 DOI: 10.1038/jcbfm.2013.173] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Revised: 08/31/2013] [Accepted: 09/08/2013] [Indexed: 02/07/2023]
Abstract
The mortality after aneurysmal subarachnoid hemorrhage (SAH) is 50%, and most survivors suffer severe functional and cognitive deficits. Half of SAH patients deteriorate 5 to 14 days after the initial bleeding, so-called delayed cerebral ischemia (DCI). Although often attributed to vasospasms, DCI may develop in the absence of angiographic vasospasms, and therapeutic reversal of angiographic vasospasms fails to improve patient outcome. The etiology of chronic neurodegenerative changes after SAH remains poorly understood. Brain oxygenation depends on both cerebral blood flow (CBF) and its microscopic distribution, the so-called capillary transit time heterogeneity (CTH). In theory, increased CTH can therefore lead to tissue hypoxia in the absence of severe CBF reductions, whereas reductions in CBF, paradoxically, improve brain oxygenation if CTH is critically elevated. We review potential sources of elevated CTH after SAH. Pericyte constrictions in relation to the initial ischemic episode and subsequent oxidative stress, nitric oxide depletion during the pericapillary clearance of oxyhemoglobin, vasogenic edema, leukocytosis, and astrocytic endfeet swelling are identified as potential sources of elevated CTH, and hence of metabolic derangement, after SAH. Irreversible changes in capillary morphology and function are predicted to contribute to long-term relative tissue hypoxia, inflammation, and neurodegeneration. We discuss diagnostic and therapeutic implications of these predictions.
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Affiliation(s)
- Leif Østergaard
- 1] Department of Neuroradiology, Aarhus University Hospital, Aarhus, Denmark [2] Center of Functionally Integrative Neuroscience and MINDLab, Aarhus University, Aarhus, Denmark
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196
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Clanton TL, Hogan MC, Gladden LB. Regulation of cellular gas exchange, oxygen sensing, and metabolic control. Compr Physiol 2013; 3:1135-90. [PMID: 23897683 DOI: 10.1002/cphy.c120030] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cells must continuously monitor and couple their metabolic requirements for ATP utilization with their ability to take up O2 for mitochondrial respiration. When O2 uptake and delivery move out of homeostasis, cells have elaborate and diverse sensing and response systems to compensate. In this review, we explore the biophysics of O2 and gas diffusion in the cell, how intracellular O2 is regulated, how intracellular O2 levels are sensed and how sensing systems impact mitochondrial respiration and shifts in metabolic pathways. Particular attention is paid to how O2 affects the redox state of the cell, as well as the NO, H2S, and CO concentrations. We also explore how these agents can affect various aspects of gas exchange and activate acute signaling pathways that promote survival. Two kinds of challenges to gas exchange are also discussed in detail: when insufficient O2 is available for respiration (hypoxia) and when metabolic requirements test the limits of gas exchange (exercising skeletal muscle). This review also focuses on responses to acute hypoxia in the context of the original "unifying theory of hypoxia tolerance" as expressed by Hochachka and colleagues. It includes discourse on the regulation of mitochondrial electron transport, metabolic suppression, shifts in metabolic pathways, and recruitment of cell survival pathways preventing collapse of membrane potential and nuclear apoptosis. Regarding exercise, the issues discussed relate to the O2 sensitivity of metabolic rate, O2 kinetics in exercise, and influences of available O2 on glycolysis and lactate production.
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Affiliation(s)
- T L Clanton
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA.
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197
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Abstract
S-nitrosothiols (RSNO) are involved in post-translational modifications of many proteins analogous to protein phosphorylation. In addition, RSNO have many physiological roles similar to nitric oxide ((•)NO), which are presumably involving the release of (•)NO from the RSNO. However, the much longer life span in biological systems for RSNO than (•)NO suggests a dominant role for RSNO in mediating (•)NO bioactivity. RSNO are detected in plasma in low nanomolar levels in healthy human subjects. These RSNO are believed to be redirecting the (•)NO to the vasculature. However, the mechanism for the formation of RSNO in vivo has not been established. We have reviewed the reactions of (•)NO with oxygen, metalloproteins, and free radicals that can lead to the formation of RSNO and have evaluated the potential for each mechanism to provide a source for RSNO in vivo.
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Affiliation(s)
- Enika Nagababu
- Molecular Dynamics Section, National Institute on Aging, National Institutes of Health, 251 Bayview Blvd, Rm No. 5B131, Baltimore, MD, 21224, USA,
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Sonoda K, Ohtake K, Kubo Y, Uchida H, Uchida M, Natsume H, Kobayashi M, Kobayashi J. Aldehyde dehydrogenase 2 partly mediates hypotensive effect of nitrite onl-NAME-induced hypertension in normoxic rat. Clin Exp Hypertens 2013; 36:410-8. [DOI: 10.3109/10641963.2013.846355] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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199
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Modulating hemoglobin nitrite reductase activity through allostery: a mathematical model. Nitric Oxide 2013; 35:193-8. [PMID: 24177061 DOI: 10.1016/j.niox.2013.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Revised: 10/15/2013] [Accepted: 10/19/2013] [Indexed: 11/23/2022]
Abstract
The production of nitric oxide by hemoglobin (Hb) has been proposed to play a major role in the control of blood flow. Because of the allosteric nature of hemoglobin, the nitrite reductase activity is a complex function of oxygen partial pressure PO2. We have previous developed a model to obtain the micro rate constants for nitrite reduction by R state (kR) and T state (kT) hemoglobin in terms of the experimental maximal macro rate constant kNmax and the corresponding oxygen concentration PO2max. However, because of the intrinsic difficulty in obtaining accurate macro rate constant kN, from available experiments, we have developed an alternative method to determine the micro reaction rate constants (kR and kT) by fitting the simulated macro reaction rate curve (kN versus PO2) to the experimental data. We then use our model to analyze the effect of pH (Bohr Effect) and blood ageing on the nitrite reductase activity, showing that the fall of bisphosphoglycerate (BPG) during red cell storage leads to increase NO production. Our model can have useful predictive and explanatory power. For example, the previously described enhanced nitrite reductase activity of ovine fetal Hb, in comparison to the adult protein, may be understood in terms of a weaker interaction with BPG and an increase in the value of kT from 0.0087M(-1)s(-1) to 0.083M(-1)s(-1).
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200
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Redox balance and cardioprotection. Basic Res Cardiol 2013; 108:392. [DOI: 10.1007/s00395-013-0392-7] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 09/24/2013] [Accepted: 10/14/2013] [Indexed: 12/11/2022]
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