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Yokomizo S, Roessing M, Morita A, Kopp T, Ogawa E, Katagiri W, Feil S, Huang PL, Atochin DN, Kashiwagi S. Near-infrared II photobiomodulation augments nitric oxide bioavailability via phosphorylation of endothelial nitric oxide synthase. FASEB J 2022; 36:e22490. [PMID: 35929438 PMCID: PMC9382775 DOI: 10.1096/fj.202101890r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 07/05/2022] [Accepted: 07/25/2022] [Indexed: 11/11/2022]
Abstract
There is solid evidence of the beneficial effect of photobiomodulation (PBM) with low-power near-infrared (NIR) light in the NIR-I window in increasing bioavailable nitric oxide (NO). However, it is not established whether this effect can be extended to NIR-II light, limiting broader applications of this therapeutic modality. Since we have demonstrated PBM with NIR laser in the NIR-II window, we determined the causal relationship between NIR-II irradiation and its specific biological effects on NO bioavailability. We analyzed the impact of NIR-II irradiation on NO release in cultured human endothelial cells using a NO-sensitive fluorescence probe and single-cell live imaging. Two distinct wavelengths of NIR-II laser (1064 and 1270 nm) and NIR-I (808 nm) at an irradiance of 10 mW/cm2 induced NO release from endothelial cells. These lasers also enhanced Akt phosphorylation at Ser 473, endothelial nitric oxide synthase (eNOS) phosphorylation at Ser 1177, and endothelial cell migration. Moreover, the NO release and phosphorylation of eNOS were abolished by inhibiting mitochondrial respiration, suggesting that Akt activation caused by NIR-II laser exposure involves mitochondrial retrograde signaling. Other inhibitors that inhibit known Akt activation pathways, including a specific inhibitor of PI3K, Src family PKC, did not affect this response. These two wavelengths of NIR-II laser induced no appreciable NO generation in cultured neuronal cells expressing neuronal NOS (nNOS). In short, NIR-II laser enhances bioavailable NO in endothelial cells. Since a hallmark of endothelial dysfunction is suppressed eNOS with concomitant NO deficiency, NIR-II laser technology could be broadly used to restore endothelial NO and treat or prevent cardiovascular diseases.
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Affiliation(s)
- Shinya Yokomizo
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, 149 13 Street, Charlestown, MA, 02129, USA
- Department of Radiological Science, Tokyo Metropolitan University, 7-2-10 Higashi-Ogu, Arakawa, Tokyo 116-8551, Japan
| | - Malte Roessing
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Auf der Morgenstelle 34, Tübingen 72076, Germany
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, 149 13 Street, Charlestown, MA 02129, USA
| | - Atsuyo Morita
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, 149 13 Street, Charlestown, MA 02129, USA
| | - Timo Kopp
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Auf der Morgenstelle 34, Tübingen 72076, Germany
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, 149 13 Street, Charlestown, MA 02129, USA
| | - Emiyu Ogawa
- School of Allied Health Science, Kitasato University, 1-15-1 Kitasato Minami-ku Sagamihara, Kanagawa, Japan
| | - Wataru Katagiri
- Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522, Japan
| | - Susanne Feil
- Interfaculty Institute of Biochemistry (IFIB), University of Tübingen, Auf der Morgenstelle 34, Tübingen 72076, Germany
| | - Paul L. Huang
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, 149 13 Street, Charlestown, MA 02129, USA
| | - Dmitriy N. Atochin
- Cardiovascular Research Center, Department of Medicine, Massachusetts General Hospital, 149 13 Street, Charlestown, MA 02129, USA
| | - Satoshi Kashiwagi
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, 149 13 Street, Charlestown, MA, 02129, USA
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Villar M, Godwin I, Hegarty R, Erler D, Farid H, Nolan J. Nitrate and nitrite absorption, recycling and retention in tissues of sheep. Small Rumin Res 2021. [DOI: 10.1016/j.smallrumres.2021.106392] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
Sudden cardiac arrest is a leading cause of death worldwide. Although the methods of cardiopulmonary resuscitation have been improved, mortality is still unacceptably high, and many survivors suffer from lasting neurological deficits due to the post-cardiac arrest syndrome (PCAS). Pathophysiologically, generalized vascular endothelial dysfunction accompanied by platelet activation and systemic inflammation has been implicated in the pathogenesis of PCAS. Because endothelial-derived nitric oxide (NO) plays a central role in maintaining vascular homeostasis, the role of NO-dependent signaling has been a focus of the intense investigation. Recent preclinical studies showed that therapeutic interventions that increase vascular NO bioavailability may improve outcomes after cardiac arrest complicated with PCAS. In particular, NO inhalation therapy has been shown to improve neurological outcomes and survival in multiple species. Clinical studies examining the safety and efficacy of inhaled NO in patients sustaining PCAS are warranted.
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Plasma nitrite as an indicator of cerebral ischemia during extracranial/intracranial bypass surgery in moyamoya patients. J Stroke Cerebrovasc Dis 2020; 29:104830. [DOI: 10.1016/j.jstrokecerebrovasdis.2020.104830] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/17/2020] [Accepted: 03/22/2020] [Indexed: 01/19/2023] Open
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Tonelli AR, Aulak KS, Ahmed MK, Hausladen A, Abuhalimeh B, Casa CJ, Rogers SC, Timm D, Doctor A, Gaston B, Dweik RA. A pilot study on the kinetics of metabolites and microvascular cutaneous effects of nitric oxide inhalation in healthy volunteers. PLoS One 2019; 14:e0221777. [PMID: 31469867 PMCID: PMC6716644 DOI: 10.1371/journal.pone.0221777] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 08/14/2019] [Indexed: 11/19/2022] Open
Abstract
RATIONALE Inhaled nitric oxide (NO) exerts a variety of effects through metabolites and these play an important role in regulation of hemodynamics in the body. A detailed investigation into the generation of these metabolites has been overlooked. OBJECTIVES We investigated the kinetics of nitrite and S-nitrosothiol-hemoglobin (SNO-Hb) in plasma derived from inhaled NO subjects and how this modifies the cutaneous microvascular response. FINDINGS We enrolled 15 healthy volunteers. Plasma nitrite levels at baseline and during NO inhalation (15 minutes at 40 ppm) were 102 (86-118) and 114 (87-129) nM, respectively. The nitrite peak occurred at 5 minutes of discontinuing NO (131 (104-170) nM). Plasma nitrate levels were not significantly different during the study. SNO-Hb molar ratio levels at baseline and during NO inhalation were 4.7E-3 (2.5E-3-5.8E-3) and 7.8E-3 (4.1E-3-13.0E-3), respectively. Levels of SNO-Hb continued to climb up to the last study time point (30 min: 10.6E-3 (5.3E-3-15.5E-3)). The response to acetylcholine iontophoresis both before and during NO inhalation was inversely associated with the SNO-Hb level (r: -0.57, p = 0.03, and r: -0.54, p = 0.04, respectively). CONCLUSIONS Both nitrite and SNO-Hb increase during NO inhalation. Nitrite increases first, followed by a more sustained increase in Hb-SNO. Nitrite and Hb-SNO could be a mobile reservoir of NO with potential implications on the systemic microvasculature.
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Affiliation(s)
- Adriano R. Tonelli
- Department of Pulmonary, Allergy and Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States of America
- Pathobiology Division, Lerner Research Institute, Cleveland Clinic, OH, United States of America
| | - Kulwant S. Aulak
- Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, OH, United States of America
| | - Mostafa K. Ahmed
- Department of Chest Diseases, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Alfred Hausladen
- Institute for Transformative Molecular Medicine and Department of Medicine, Case Western Reserve University School of Medicine and University Hospitals Cleveland Medical Center, Cleveland, OH, United States of America
| | - Batool Abuhalimeh
- Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, OH, United States of America
| | - Charlie J. Casa
- Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, OH, United States of America
| | - Stephen C. Rogers
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - David Timm
- Department of Psychiatry, School of Medicine, Washington University, St. Louis, MO, United States of America
| | - Allan Doctor
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Benjamin Gaston
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States of America
| | - Raed A. Dweik
- Department of Pulmonary, Allergy and Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, OH, United States of America
- Pathobiology Division, Lerner Research Institute, Cleveland Clinic, OH, United States of America
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Jung H, Choi EK, Baek SI, Cho C, Jin Y, Kwak KH, Jeon Y, Park SS, Kim S, Lim DG. The Effect of Nitric Oxide on Remote Ischemic Preconditioning in Renal Ischemia Reperfusion Injury in Rats. Dose Response 2019; 17:1559325819853651. [PMID: 31191188 PMCID: PMC6542129 DOI: 10.1177/1559325819853651] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 12/12/2022] Open
Abstract
Although remote ischemic preconditioning (RIPC) is an organ-protective maneuver from subsequent ischemia reperfusion injury (IRI) by application of brief ischemia and reperfusion to other organs, its mechanism remains unclear. However, it is known that RIPC reduces the heart, brain, and liver IRI, and that nitric oxide (NO) is involved in the mechanism of this effect. To identify the role of NO in the protective effect of RIPC in renal IRI, this study examined renal function, oxidative status, and histopathological changes using N-nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor. Remote ischemic preconditioning was produced by 3 cycles of 5 minutes ischemia and 5 minutes reperfusion. Blood urea nitrogen, creatinine (Cr), and renal tissue malondialdehyde levels were lower, histopathological damage was less severe, and superoxide dismutase level was higher in the RIPC + IRI group than in the IRI group. The renoprotective effect was reversed by L-NAME. Obtained results suggest that RIPC before renal IRI contributes to improvement of renal function, increases antioxidative marker levels, and decreases oxidative stress marker levels and histopathological damage. Moreover, NO is likely to play an important role in this protective effect of RIPC on renal IRI.
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Affiliation(s)
- Hoon Jung
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Eun Kyung Choi
- Department of Anesthesiology and Pain Medicine, Yeungnam University College of Medicine, Daegu, Republic of Korea
| | - Seung Ik Baek
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Changhee Cho
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Yehun Jin
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Kyung Hwa Kwak
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Younghoon Jeon
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Sung-Sik Park
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Sioh Kim
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Dong Gun Lim
- Department of Anesthesiology and Pain Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
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Circulating mediators of remote ischemic preconditioning: search for the missing link between non-lethal ischemia and cardioprotection. Oncotarget 2019; 10:216-244. [PMID: 30719216 PMCID: PMC6349428 DOI: 10.18632/oncotarget.26537] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 12/10/2018] [Indexed: 12/11/2022] Open
Abstract
Acute myocardial infarction (AMI) is one of the leading causes of mortality and morbidity worldwide. There has been an extensive search for cardioprotective therapies to reduce myocardial ischemia-reperfusion (I/R) injury. Remote ischemic preconditioning (RIPC) is a phenomenon that relies on the body's endogenous protective modalities against I/R injury. In RIPC, non-lethal brief I/R of one organ or tissue confers protection against subsequent lethal I/R injury in an organ remote to the briefly ischemic organ or tissue. Initially it was believed to be limited to direct myocardial protection, however it soon became apparent that RIPC applied to other organs such as kidney, liver, intestine, skeletal muscle can reduce myocardial infarct size. Intriguing discoveries have been made in extending the concept of RIPC to other organs than the heart. Over the years, the underlying mechanisms of RIPC have been widely sought and discussed. The involvement of blood-borne factors as mediators of RIPC has been suggested by a number of research groups. The main purpose of this review article is to summarize the possible circulating mediators of RIPC, and recent studies to establish the clinical efficacy of these mediators in cardioprotection from lethal I/R injury.
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Lim H, Lee SK, Kim G. Hemodynamic Implications of Carbon Monoxide (CO) and Nitrogen Oxide (NO) during Living Donor Liver Transplantation. TOHOKU J EXP MED 2017; 243:179-186. [PMID: 29176268 DOI: 10.1620/tjem.243.179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Carbon monoxide (CO) and nitrogen oxide (NO) affect vasodilation and cause hemodynamic change. Hemodynamic instability due to liver transplantation may result in poor prognosis of graft. This study investigated the hemodynamic implications of CO and NO levels measured using carboxyhemoglobin (COHb) and methemoglobin (MetHb) during living donor liver transplantation (LDLT). The hemodynamic instability with a pressor dose (norepinephrine equivalent) was estimated 1 hour after graft reperfusion. COHb and MetHb were used as indexes of CO and NO, and were measured using an arterial blood gas analyzer. One hundred and ten recipients who underwent LDLT from May 2011 to July 2013 were selected. Recipients were divided into high (≥ 1.9%) and low (< 1.9%) COHb groups with COHb concentrations at 5 minutes after reperfusion. Recipients were also divided into high (≥ 0.4%) and low (< 0.4%) MetHb groups with MetHb concentrations at 30 minutes after reperfusion. Data are presented as mean ± standard deviation or number (percentage). Model for End-stage Liver Disease (MELD) scores were different for the two COHb groups (low: 13.4 ± 9.0 vs. high: 19.7 ± 10.6, p < 0.001), and pressor doses adjusted by MELD scores were also different between the two COHb groups (low: 0.09 ± 0.01 μg/kg/min vs. high: 0.14 ± 0.01 μg/kg/min, p = 0.029). By contrast, pressor doses and MELD scores were not different between the two MetHb groups. In conclusion, CO rather than NO has hemodynamic implications during LDLT. Therefore, the increase in COHb during LDLT is predictive of hemodynamic instability.
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Affiliation(s)
- Hyunyoung Lim
- Department of Anesthesiology and Pain Medicine, Hanyang University Medical Center
| | - Suk-Koo Lee
- Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine
| | - Gaabsoo Kim
- Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine
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Low dose nitrite improves reoxygenation following renal ischemia in rats. Sci Rep 2017; 7:14597. [PMID: 29097777 PMCID: PMC5668317 DOI: 10.1038/s41598-017-15058-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/16/2017] [Indexed: 11/09/2022] Open
Abstract
In hypoxic and acidic tissue environments, nitrite is metabolised to nitric oxide, thus, bringing about novel therapeutic options in myocardial infarction, peripheral artery disease, stroke, and hypertension. Following renal ischemia, reperfusion of the kidney remains incomplete and tissue oxygenation is reduced for several minutes to hours. Thus, in renal ischemia-reperfusion injury, providing nitrite may have outstanding therapeutic value. Here we demonstrate nitrite's distinct potential to rapidly restore tissue oxygenation in the renal cortex and medulla after 45 minutes of complete unilateral kidney ischemia in the rat. Notably, tissue oxygenation was completely restored, while tissue perfusion did not fully reach pre-ischemia levels within 60 minutes of reperfusion. Nitrite was infused intravenously in a dose, which can be translated to the human. Specifically, methaemoglobin did not exceed 3%, which is biologically negligible. Hypotension was not observed. Providing nitrite well before ischemia and maintaining nitrite infusion throughout the reperfusion period prevented the increase in serum creatinine by ischemia reperfusion injury. In conclusion, low-dose nitrite restores renal tissue oxygenation in renal ischemia reperfusion injury and enhances regional kidney post-ischemic perfusion. As nitrite provides nitric oxide predominantly in hypoxic tissues, it may prove a specific measure to reduce renal ischemia reperfusion injury.
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Schroeder HJ, Kanda E, Power GG, Blood AB. Fetal-maternal nitrite exchange in sheep: Experimental data, a computational model and an estimate of placental nitrite permeability. Placenta 2016; 38:67-75. [PMID: 26907384 PMCID: PMC4768312 DOI: 10.1016/j.placenta.2015.12.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 12/12/2015] [Accepted: 12/16/2015] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Nitrite conveys NO-bioactivity that may contribute to the high-flow, low-resistance character of the fetal circulation. Fetal blood nitrite concentrations depend partly on placental permeability which has not been determined experimentally. We aimed to extract the placental permeability-surface (PS) product for nitrite in sheep from a computational model. METHODS An eight-compartment computational model of the fetal-maternal unit was constructed (Matlab(®) (R2013b (8.2.0.701), MathWorks Inc., Natick, MA). Taking into account fetal and maternal body weights, four variables (PS, the rate of nitrite metabolism within red cells, and two nitrite distribution volumes, one with and one without nitrite metabolism), were varied to obtain optimal fits to the experimental plasma nitrite profiles observed following the infusion of nitrite into either the fetus (n = 7) or the ewe (n = 8). RESULTS The model was able to replicate the average and individual nitrite-time profiles (r(2) > 0.93) following both fetal and maternal nitrite infusions with reasonable variation of the four fitting parameters. Simulated transplacental nitrite fluxes were able to predict umbilical arterial-venous nitrite concentration differences that agreed with experimental values. The predicted PS values for a 3 kg sheep fetus were 0.024 ± 0.005 l∙min(-1) in the fetal-maternal direction and 0.025 ± 0.003 l∙min(-1) in the maternal-fetal direction (mean ± SEM). These values are many-fold higher than the reported PS product for chloride anions across the sheep placenta. CONCLUSION The result suggests a transfer of nitrite across the sheep placenta that is not exclusively by simple diffusion through water-filled channels.
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Affiliation(s)
- Hobe J Schroeder
- Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Eriko Kanda
- Department of Pediatrics, Division of Neonatology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Gordon G Power
- Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, USA
| | - Arlin B Blood
- Department of Pediatrics, Division of Neonatology, Loma Linda University School of Medicine, Loma Linda, CA, USA; Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, USA.
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Zemke AC, Shiva S, Burns JL, Moskowitz SM, Pilewski JM, Gladwin MT, Bomberger JM. Nitrite modulates bacterial antibiotic susceptibility and biofilm formation in association with airway epithelial cells. Free Radic Biol Med 2014; 77:307-16. [PMID: 25229185 PMCID: PMC4278422 DOI: 10.1016/j.freeradbiomed.2014.08.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/08/2014] [Accepted: 08/04/2014] [Indexed: 11/16/2022]
Abstract
Pseudomonas aeruginosa is the major pathogenic bacteria in cystic fibrosis and other forms of bronchiectasis. Growth in antibiotic-resistant biofilms contributes to the virulence of this organism. Sodium nitrite has antimicrobial properties and has been tolerated as a nebulized compound at high concentrations in human subjects with pulmonary hypertension; however, its effects have not been evaluated on biotic biofilms or in combination with other clinically useful antibiotics. We grew P. aeruginosa on the apical surface of primary human airway epithelial cells to test the efficacy of sodium nitrite against biotic biofilms. Nitrite alone prevented 99% of biofilm growth. We then identified significant cooperative interactions between nitrite and polymyxins. For P. aeruginosa growing on primary CF airway cells, combining nitrite and colistimethate resulted in an additional log of bacterial inhibition compared to treating with either agent alone. Nitrite and colistimethate additively inhibited oxygen consumption by P. aeruginosa. Surprisingly, whereas the antimicrobial effects of nitrite in planktonic, aerated cultures are nitric oxide (NO) dependent, antimicrobial effects under other growth conditions are not. The inhibitory effect of nitrite on bacterial oxygen consumption and biofilm growth did not require NO as an intermediate as chemically scavenging NO did not block growth inhibition. These data suggest an NO-radical independent nitrosative or oxidative inhibition of respiration. The combination of nebulized sodium nitrite and colistimethate may provide a novel therapy for chronic P. aeruginosa airway infections, because sodium nitrite, unlike other antibiotic respiratory chain "poisons," can be safely nebulized at high concentration in humans.
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Affiliation(s)
- Anna C Zemke
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Sruti Shiva
- Department of Pharmacology, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Jane L Burns
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Samuel M Moskowitz
- Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Joseph M Pilewski
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Mark T Gladwin
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA; Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Pittsburgh, PA 15219, USA
| | - Jennifer M Bomberger
- Department of Microbiology and Molecular Genetics, University of Pittsburgh, Pittsburgh, PA 15219, USA.
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Rassaf T, Totzeck M, Hendgen-Cotta UB, Shiva S, Heusch G, Kelm M. Circulating nitrite contributes to cardioprotection by remote ischemic preconditioning. Circ Res 2014; 114:1601-10. [PMID: 24643960 DOI: 10.1161/circresaha.114.303822] [Citation(s) in RCA: 262] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
RATIONALE Remote ischemic preconditioning (rIPC) with short episodes of ischemia/reperfusion (I/R) of an organ remote from the heart is a powerful approach to protect against myocardial I/R injury. The signal transduction pathways for the cross talk between the remote site and the heart remain unclear in detail. OBJECTIVE To elucidate the role of circulating nitrite in cardioprotection by rIPC. METHODS AND RESULTS Mice were subjected to 4 cycles of no-flow ischemia with subsequent reactive hyperemia within the femoral region and underwent in vivo myocardial I/R (30 minutes/5 minutes or 24 hours). The mouse experiments were conducted using genetic and pharmacological approaches. Shear stress-dependent stimulation of endothelial nitric oxide synthase within the femoral artery during reactive hyperemia yielded substantial release of nitric oxide, subsequently oxidized to nitrite and transferred humorally to the myocardium. Within the heart, reduction of nitrite to nitric oxide by cardiac myoglobin and subsequent S-nitrosation of mitochondrial membrane proteins reduced mitochondrial respiration, reactive oxygen species formation, and myocardial infarct size. Pharmacological and genetic inhibition of nitric oxide/nitrite generation by endothelial nitric oxide synthase at the remote site or nitrite bioactivation by myoglobin within the target organ abrogated the cardioprotection by rIPC. Transfer experiments of plasma from healthy volunteers subjected to rIPC of the arm identified plasma nitrite as a cardioprotective agent in isolated Langendorff mouse heart preparations exposed to I/R. CONCLUSIONS Circulating nitrite derived from shear stress-dependent stimulation of endothelial nitric oxide synthase at the remote site of rIPC contributes to cardioprotection during I/R. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT01259739.
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Affiliation(s)
- Tienush Rassaf
- From the Department of Medicine, Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Hospital Duesseldorf, Duesseldorf, Germany (T.R., M.T., U.B.H.-C., M.K.); Department of Pharmacology and Chemical Biology, University of Pittsburgh, PA (S.S.); Institute for Pathophysiology, University of Essen, Essen, Germany (G.H.); and Cardiovascular Research Institute Duesseldorf, Duesseldorf, Germany (M.K.)
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Sindler AL, Devan AE, Fleenor BS, Seals DR. Inorganic nitrite supplementation for healthy arterial aging. J Appl Physiol (1985) 2014; 116:463-77. [PMID: 24408999 PMCID: PMC3949212 DOI: 10.1152/japplphysiol.01100.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 01/03/2014] [Indexed: 12/12/2022] Open
Abstract
Aging is the major risk factor for cardiovascular diseases (CVD). This is attributable primarily to adverse changes in arteries, notably, increases in large elastic artery stiffness and endothelial dysfunction mediated by inadequate concentrations of the vascular-protective molecule, nitric oxide (NO), and higher levels of oxidative stress and inflammation. Inorganic nitrite is a promising precursor molecule for augmenting circulating and tissue NO bioavailability because it requires only a one-step reduction to NO. Nitrite also acts as an independent signaling molecule, exerting many of the effects previously attributed to NO. Results of recent studies indicate that nitrite may be effective in the treatment of vascular aging. In old mice, short-term oral sodium nitrite supplementation reduces aortic pulse wave velocity, the gold-standard measure of large elastic artery stiffness, and ameliorates endothelial dysfunction, as indicated by normalization of NO-mediated endothelium-dependent dilation. These improvements in age-related vascular dysfunction with nitrite are mediated by reductions in oxidative stress and inflammation, and may be linked to increases in mitochondrial biogenesis and health. Increasing nitrite levels via dietary intake of nitrate appears to have similarly beneficial effects in many of the same physiological and clinical settings. Several clinical trials are being performed to determine the broad therapeutic potential of increasing nitrite bioavailability on human health and disease, including studies related to vascular aging. In summary, inorganic nitrite, as well as dietary nitrate supplementation, represents a promising therapy for treatment of arterial aging and prevention of age-associated CVD in humans.
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Affiliation(s)
- Amy L Sindler
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado
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Gherasim C, Yadav PK, Kabil O, Niu WN, Banerjee R. Nitrite reductase activity and inhibition of H₂S biogenesis by human cystathionine ß-synthase. PLoS One 2014; 9:e85544. [PMID: 24416422 PMCID: PMC3885727 DOI: 10.1371/journal.pone.0085544] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 12/04/2013] [Indexed: 12/18/2022] Open
Abstract
Nitrite was recognized as a potent vasodilator >130 years and has more recently emerged as an endogenous signaling molecule and modulator of gene expression. Understanding the molecular mechanisms that regulate nitrite metabolism is essential for its use as a potential diagnostic marker as well as therapeutic agent for cardiovascular diseases. In this study, we have identified human cystathionine ß-synthase (CBS) as a new player in nitrite reduction with implications for the nitrite-dependent control of H2S production. This novel activity of CBS exploits the catalytic property of its unusual heme cofactor to reduce nitrite and generate NO. Evidence for the possible physiological relevance of this reaction is provided by the formation of ferrous-nitrosyl (FeII-NO) CBS in the presence of NADPH, the human diflavin methionine synthase reductase (MSR) and nitrite. Formation of FeII-NO CBS via its nitrite reductase activity inhibits CBS, providing an avenue for regulating biogenesis of H2S and cysteine, the limiting reagent for synthesis of glutathione, a major antioxidant. Our results also suggest a possible role for CBS in intracellular NO biogenesis particularly under hypoxic conditions. The participation of a regulatory heme cofactor in CBS in nitrite reduction is unexpected and expands the repertoire of proteins that can liberate NO from the intracellular nitrite pool. Our results reveal a potential molecular mechanism for cross-talk between nitrite, NO and H2S biology.
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Affiliation(s)
- Carmen Gherasim
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Pramod K. Yadav
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Omer Kabil
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Wei-Ning Niu
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- School of Life Science, Northwestern Polytechnical University, Xi’an, China
| | - Ruma Banerjee
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
- * E-mail:
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15
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Abstract
The identification of endothelium-derived relaxing factor as nitric oxide (NO) dramatically altered the course of vascular biology, as well as other biomedical disciplines. The ubiquity of this natural product of cell metabolism and the complexity of its biochemistry provide a rich source of molecular mediators of phenotype in health and disease.
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Affiliation(s)
- Joseph Loscalzo
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
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16
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Quantitative Systems Pharmacology Model of NO Metabolome and Methemoglobin Following Long-Term Infusion of Sodium Nitrite in Humans. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2013; 2:e60. [PMID: 23903463 PMCID: PMC3731826 DOI: 10.1038/psp.2013.35] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 05/09/2013] [Indexed: 01/08/2023]
Abstract
A long-term sodium nitrite infusion is intended for the treatment of vascular disorders. Phase I data demonstrated a significant nonlinear dose-exposure-toxicity relationship within the therapeutic dosage range. This study aims to develop a quantitative systems pharmacology model characterizing nitric oxide (NO) metabolome and methemoglobin after sodium nitrite infusion. Nitrite, nitrate, and methemoglobin concentration–time profiles in plasma and RBC were used for model development. Following intravenous sodium nitrite administration, nitrite undergoes conversion in RBC and tissue. Nitrite sequestered by RBC interacts more extensively with deoxyhemoglobin, which contributes greatly to methemoglobin formation. Methemoglobin is formed less-than-proportionally at higher nitrite doses as characterized with facilitated methemoglobin removal. Nitrate-to-nitrite reduction occurs in tissue and via entero-salivary recirculation. The less-than-proportional increase in nitrite and nitrate exposure at higher nitrite doses is modeled with a dose-dependent increase in clearance. The model provides direct insight into NO metabolome disposition and is valuable for nitrite dosing selection in clinical trials.
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17
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Samal AA, Honavar J, Brandon A, Bradley KM, Doran S, Liu Y, Dunaway C, Steele C, Postlethwait EM, Squadrito GL, Fanucchi MV, Matalon S, Patel RP. Administration of nitrite after chlorine gas exposure prevents lung injury: effect of administration modality. Free Radic Biol Med 2012; 53:1431-9. [PMID: 22917977 PMCID: PMC3448851 DOI: 10.1016/j.freeradbiomed.2012.08.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 07/14/2012] [Accepted: 08/06/2012] [Indexed: 12/20/2022]
Abstract
Cl(2) gas toxicity is complex and occurs during and after exposure, leading to acute lung injury (ALI) and reactive airway syndrome (RAS). Moreover, Cl(2) exposure can occur in diverse situations encompassing mass casualty scenarios, highlighting the need for postexposure therapies that are efficacious and amenable to rapid and easy administration. In this study, we assessed the efficacy of a single dose of nitrite (1 mg/kg) to decrease ALI when administered to rats via intraperitoneal (ip) or intramuscular (im) injection 30 min after Cl(2) exposure. Exposure of rats to Cl(2) gas (400 ppm, 30 min) significantly increased ALI and caused RAS 6-24h postexposure as indexed by BAL sampling of lung surface protein and polymorphonucleocytes (PMNs) and increased airway resistance and elastance before and after methacholine challenge. Intraperitoneal nitrite decreased Cl(2)-dependent increases in BAL protein but not PMNs. In contrast im nitrite decreased BAL PMN levels without decreasing BAL protein in a xanthine oxidoreductase-dependent manner. Histological evaluation of airways 6h postexposure showed significant bronchial epithelium exfoliation and inflammatory injury in Cl(2)-exposed rats. Both ip and im nitrite improved airway histology compared to Cl(2) gas alone, but more coverage of the airway by cuboidal or columnar epithelium was observed with im compared to ip nitrite. Airways were rendered more sensitive to methacholine-induced resistance and elastance after Cl(2) gas exposure. Interestingly, im nitrite, but not ip nitrite, significantly decreased airway sensitivity to methacholine challenge. Further evaluation and comparison of im and ip therapy showed a twofold increase in circulating nitrite levels with the former, which was associated with reversal of post-Cl(2) exposure-dependent increases in circulating leukocytes. Halving the im nitrite dose resulted in no effect in PMN accumulation but significant reduction of BAL protein levels, indicating a distinct nitrite dose dependence for inhibition of Cl(2)-dependent lung permeability and inflammation. These data highlight the potential for nitrite as a postexposure therapeutic for Cl(2) gas-induced lung injury and also suggest that administration modality is a key consideration in nitrite therapeutics.
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Affiliation(s)
- Andrey A. Samal
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Jaideep Honavar
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Angela Brandon
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Kelley M. Bradley
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Stephen Doran
- Department of Medicine, University of Alabama at Birmingham, Birmingham AL 35294
| | - Yanping Liu
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Chad Dunaway
- Department of Medicine, University of Alabama at Birmingham, Birmingham AL 35294
| | - Chad Steele
- Department of Medicine, University of Alabama at Birmingham, Birmingham AL 35294
| | - Edward M. Postlethwait
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Pulmonary Injury and Repair, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Radical Biology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Giuseppe L. Squadrito
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Pulmonary Injury and Repair, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Radical Biology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Michelle V. Fanucchi
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Pulmonary Injury and Repair, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Radical Biology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Sadis Matalon
- Department of Anesthesiology, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Pulmonary Injury and Repair, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Radical Biology, University of Alabama at Birmingham, Birmingham AL 35294
| | - Rakesh P. Patel
- Department of Pathology, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Pulmonary Injury and Repair, University of Alabama at Birmingham, Birmingham AL 35294
- Center for Radical Biology, University of Alabama at Birmingham, Birmingham AL 35294
- Corresponding author: Dr. Rakesh Patel, Department of Pathology, University of, Alabama at Birmingham, 901 19 St. South, BMRII 532, Birmingham, AL 35294, , Telephone: (205)9975-9225 Fax: (205)934-7447
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18
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Hellsten Y, Nyberg M, Mortensen SP. Contribution of intravascular versus interstitial purines and nitric oxide in the regulation of exercise hyperaemia in humans. J Physiol 2012; 590:5015-23. [PMID: 22733661 DOI: 10.1113/jphysiol.2012.234963] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The regulation of blood flow to skeletal muscle involves a complex interaction between several locally formed vasodilators that are produced both in the skeletal muscle interstitium and intravascularly. The gas nitric oxide (NO) and the purines ATP and adenosine, are potent vasodilators that are formed by multiple cell types and released into the skeletal muscle interstitium and in plasma in response to muscle contraction. Cellular sources of ATP and NO in plasma are erythrocytes and endothelial cells, whereas interstitial sources are skeletal muscle cells and endothelial cells. Adenosine originates primarily from extracellular degradation of ATP. During exercise the concentrations of ATP and adenosine increase markedly in the interstitium with smaller increases occurring in plasma, and thus the interstitial concentration during exercise is severalfold higher than in plasma. The concentration of NO metabolites (NOx) in interstitium and plasma does not change during exercise and is similar in the two compartments. Adenosine and NO have been shown to contribute to exercise hyperaemia whereas the role of ATP remains unclear due to lack of specific purinergic receptor blockers. The relative role of intravascular versus interstitial vasodilators is not known but evidence suggests that both compartments are important. In cardiovascular disease, a reduced capacity to form adenosine in the muscle interstitium may be a contributing factor in increased peripheral vascular resistance.
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Affiliation(s)
- Y Hellsten
- Department of Exercise and Sport Sciences, University of Copenhagen, Universitetsparken 1, DK-2100 Copenhagen Ø, Denmark.
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19
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Scicinski J, Oronsky B, Taylor M, Luo G, Musick T, Marini J, Adams CM, Fitch WL. Preclinical evaluation of the metabolism and disposition of RRx-001, a novel investigative anticancer agent. Drug Metab Dispos 2012; 40:1810-6. [PMID: 22699395 DOI: 10.1124/dmd.112.046755] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
RRx-001 has shown promise as a novel cancer therapeutic agent. The disposition of RRx-001 was evaluated in vitro and after intravenous administration to rats. At both 24 and 168 h after a single intravenous administration of ¹⁴C-RRx-001 (10 mg/kg), the majority of radiolabel was in the blood. The recovery of label in excreta was quite low, but the major route of radiolabel excretion was via the kidney, with approximately 26% in the urine by the first 8 h and decreasing amounts in all subsequent collections to a total of 36.3% by 168 h. The partitioning of total radioactivity in red blood cells (RBCs) and plasma was determined after in vitro addition to human, rat, dog, and monkey whole blood at 1 and 20 μM. In rat, at 30 min, approximately 75% of the radioactivity is associated with RBCs and 25% with plasma. In human, at 30 min, approximately 25% of the radioactivity is associated with RBCs and 75% with plasma. Analysis by liquid chromatography/radiodetection/mass spectrometry showed that ¹⁴C-RRx-001 reacted rapidly with whole blood to give four major soluble metabolites: the GSH and Cys adducts of RRx-001 (M1 and M2) and the corresponding mononitro GSH and Cys adducts (M3 and M4). Human Hb was incubated with cold RRx-001 in buffer, and a standard proteomics protocol was used to separate and identify the tryptic peptides. Standard peptide collision-induced fragment ions supported the structure of the peptide GTFATLSELHCDK with the alkylation on the Cys-93 locus of the Hb β chain.
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20
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Wang L, Frizzell SA, Zhao X, Gladwin MT. Normoxic cyclic GMP-independent oxidative signaling by nitrite enhances airway epithelial cell proliferation and wound healing. Nitric Oxide 2012; 26:203-10. [PMID: 22425780 DOI: 10.1016/j.niox.2012.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 02/09/2012] [Accepted: 03/01/2012] [Indexed: 12/26/2022]
Abstract
The airway epithelium provides important barrier and host defense functions. Recent studies reveal that nitrite is an endocrine reservoir of nitric oxide (NO) bioactivity that is converted to NO by enzymatic reductases along the physiological oxygen gradient. Nitrite signaling has been described as NO dependent activation mediated by reactions with deoxygenated redox active hemoproteins, such as hemoglobin, myoglobin, neuroglobin, xanthine oxidoreductase (XO) and NO synthase at low pH and oxygen tension. However, nitrite can also be readily oxidized to nitrogen dioxide (NO(2)·) via heme peroxidase reactions, suggesting the existence of alternative oxidative signaling pathways for nitrite under normoxic conditions. In the present study, we examined normoxic signaling effects of sodium nitrite on airway epithelial cell wound healing. In an in vitro scratch injury model under normoxia, we exposed cultured monolayers of human airway epithelial cells to various concentrations of sodium nitrite and compared responses to NO donor. We found sodium nitrite potently enhanced airway epithelium wound healing at physiological concentrations (from 1 μM). The effect of nitrite was blocked by the NO and NO(2)· scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO). Interestingly, nitrite treatment did not increase cyclic guanosine monophosphate (cGMP) levels under these normoxic conditions, even in the presence of a phosphodiesterase 5 inhibitor, suggesting cGMP independent signaling. Consistent with an oxidative signaling pathway requiring hydrogen peroxide (H(2)O(2))/heme-peroxidase/NO(2)· signaling, the effects of nitrite were potentiated by superoxide dismutase (SOD) and low concentration H(2)O(2), whereas inhibited completely by catalase, followed by downstream extracellular-signal-regulated kinase (ERK) 1/2 activation. Our data represent the first description of normoxic nitrite signaling on lung epithelial cell proliferation and wound healing and suggest novel oxidative signaling pathways involving nitrite-H(2)O(2) reactions, possibly via the intermediary, NO(2)·.
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Affiliation(s)
- Ling Wang
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
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21
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Doherty GH. Nitric oxide in neurodegeneration: potential benefits of non-steroidal anti-inflammatories. Neurosci Bull 2011; 27:366-82. [PMID: 22108814 PMCID: PMC5560384 DOI: 10.1007/s12264-011-1530-6] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 09/13/2011] [Indexed: 12/28/2022] Open
Abstract
The cellular messenger nitric oxide (NO) has been linked to neurodegenerative disorders due to the increased expression of the enzymes that catalyze its synthesis in postmortem tissues derived from sufferers of these diseases. Nitrated proteins have also been detected in these samples, revealing that NO is biologically active in regions damaged during neurodegeneration. Modulation of NO levels has been reported not only in the neurons of the central nervous system, but also in the glial cells (microglia and astroglia) activated during the neuroinflammatory response. Neuroinflammation has been found in some neurodegenerative conditions, and inhibition of these neuroinflammatory signals has been shown to delay the progress of such disorders. Thus NO and the pathways triggering its release are emerging as an important research focus in the search for strategies to prevent, halt or cure neurodegenerative diseases.
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Affiliation(s)
- Gayle Helane Doherty
- School of Biology, St Andrews University, St Andrews, Fife KY169TS, United Kingdom.
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22
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Pluta RM, Oldfield EH, Bakhtian KD, Fathi AR, Smith RK, Devroom HL, Nahavandi M, Woo S, Figg WD, Lonser RR. Safety and feasibility of long-term intravenous sodium nitrite infusion in healthy volunteers. PLoS One 2011; 6:e14504. [PMID: 21249218 PMCID: PMC3018414 DOI: 10.1371/journal.pone.0014504] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 12/10/2010] [Indexed: 11/19/2022] Open
Abstract
Background Infusion of sodium nitrite could provide sustained therapeutic concentrations of nitric oxide (NO) for the treatment of a variety of vascular disorders. The study was developed to determine the safety and feasibility of prolonged sodium nitrite infusion. Methodology Healthy volunteers, aged 21 to 60 years old, were candidates for the study performed at the National Institutes of Health (NIH; protocol 05-N-0075) between July 2007 and August 2008. All subjects provided written consent to participate. Twelve subjects (5 males, 7 females; mean age, 38.8±9.2 years (range, 21–56 years)) were intravenously infused with increasing doses of sodium nitrite for 48 hours (starting dose at 4.2 µg/kg/hr; maximal dose of 533.8 µg/kg/hr). Clinical, physiologic and laboratory data before, during and after infusion were analyzed. Findings The maximal tolerated dose for intravenous infusion of sodium nitrite was 267 µg/kg/hr. Dose limiting toxicity occurred at 446 µg/kg/hr. Toxicity included a transient asymptomatic decrease of mean arterial blood pressure (more than 15 mmHg) and/or an asymptomatic increase of methemoglobin level above 5%. Nitrite, nitrate, S-nitrosothiols concentrations in plasma and whole blood increased in all subjects and returned to preinfusion baseline values within 12 hours after cessation of the infusion. The mean half-life of nitrite estimated at maximal tolerated dose was 45.3 minutes for plasma and 51.4 minutes for whole blood. Conclusion Sodium nitrite can be safely infused intravenously at defined concentrations for prolonged intervals. These results should be valuable for developing studies to investigate new NO treatment paradigms for a variety of clinical disorders, including cerebral vasospasm after subarachnoid hemorrhage, and ischemia of the heart, liver, kidney and brain, as well as organ transplants, blood-brain barrier modulation and pulmonary hypertension. Clinical Trial Registration Information http://www.clinicaltrials.gov; NCT00103025
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Affiliation(s)
- Ryszard M Pluta
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America.
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