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Gao F, Hayashi Y, Saravanaperumal SA, Gajdos GB, Syed SA, Bhagwate AV, Ye Z, Zhong J, Zhang Y, Choi EL, Kvasha SM, Kaur J, Paradise BD, Cheng L, Simone BW, Wright AM, Kellogg TA, Kendrick ML, McKenzie TJ, Sun Z, Yan H, Yu C, Bharucha AE, Linden DR, Lee JH, Ordog T. Hypoxia-Inducible Factor 1α Stabilization Restores Epigenetic Control of Nitric Oxide Synthase 1 Expression and Reverses Gastroparesis in Female Diabetic Mice. Gastroenterology 2023; 165:1458-1474. [PMID: 37597632 PMCID: PMC10840755 DOI: 10.1053/j.gastro.2023.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 07/18/2023] [Accepted: 08/09/2023] [Indexed: 08/21/2023]
Abstract
BACKGROUND & AIMS Although depletion of neuronal nitric oxide synthase (NOS1)-expressing neurons contributes to gastroparesis, stimulating nitrergic signaling is not an effective therapy. We investigated whether hypoxia-inducible factor 1α (HIF1A), which is activated by high O2 consumption in central neurons, is a Nos1 transcription factor in enteric neurons and whether stabilizing HIF1A reverses gastroparesis. METHODS Mice with streptozotocin-induced diabetes, human and mouse tissues, NOS1+ mouse neuroblastoma cells, and isolated nitrergic neurons were studied. Gastric emptying of solids and volumes were determined by breath test and single-photon emission computed tomography, respectively. Gene expression was analyzed by RNA-sequencing, microarrays, immunoblotting, and immunofluorescence. Epigenetic assays included chromatin immunoprecipitation sequencing (13 targets), chromosome conformation capture sequencing, and reporter assays. Mechanistic studies used Cre-mediated recombination, RNA interference, and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-mediated epigenome editing. RESULTS HIF1A signaling from physiological intracellular hypoxia was active in mouse and human NOS1+ myenteric neurons but reduced in diabetes. Deleting Hif1a in Nos1-expressing neurons reduced NOS1 protein by 50% to 92% and delayed gastric emptying of solids in female but not male mice. Stabilizing HIF1A with roxadustat (FG-4592), which is approved for human use, restored NOS1 and reversed gastroparesis in female diabetic mice. In nitrergic neurons, HIF1A up-regulated Nos1 transcription by binding and activating proximal and distal cis-regulatory elements, including newly discovered super-enhancers, facilitating RNA polymerase loading and pause-release, and by recruiting cohesin to loop anchors to alter chromosome topology. CONCLUSIONS Pharmacologic HIF1A stabilization is a novel, translatable approach to restoring nitrergic signaling and treating diabetic gastroparesis. The newly recognized effects of HIF1A on chromosome topology may provide insights into physioxia- and ischemia-related organ function.
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Affiliation(s)
- Fei Gao
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Department of Gastroenterology, First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China
| | - Yujiro Hayashi
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Siva Arumugam Saravanaperumal
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Gabriella B Gajdos
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Sabriya A Syed
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, Minnesota
| | - Aditya V Bhagwate
- Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota
| | - Zhenqing Ye
- Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota
| | - Jian Zhong
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota
| | - Yuebo Zhang
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Egan L Choi
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Sergiy M Kvasha
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Jagneet Kaur
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Brooke D Paradise
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, Minnesota
| | - Liang Cheng
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota
| | - Brandon W Simone
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, Minnesota
| | - Alec M Wright
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Todd A Kellogg
- Department of Surgery, Mayo Clinic, Rochester, Minnesota
| | | | | | - Zhifu Sun
- Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota; Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota
| | - Huihuang Yan
- Division of Computational Biology, Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota; Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota
| | - Chuanhe Yu
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - Adil E Bharucha
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota
| | - David R Linden
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Jeong-Heon Lee
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota; Division of Experimental Pathology and Laboratory Medicine, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Tamas Ordog
- Enteric NeuroScience Program and Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Gastroenterology Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota; Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota.
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2
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Dugbartey GJ. Nitric oxide in kidney transplantation. Biomed Pharmacother 2023; 167:115530. [PMID: 37722191 DOI: 10.1016/j.biopha.2023.115530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/05/2023] [Accepted: 09/15/2023] [Indexed: 09/20/2023] Open
Abstract
Kidney transplantation is the treatment of choice for patients with kidney failure. Compared to dialysis therapy, it provides better quality of life and confers significant survival advantage at a relatively lower cost. However, the long-term success of this life-saving intervention is severely hampered by an inexorable clinical problem referred to as ischemia-reperfusion injury (IRI), and increases the incidence of post-transplant complications including loss of renal graft function and death of transplant recipients. Burgeoning evidence shows that nitric oxide (NO), a poisonous gas at high concentrations, and with a historic negative public image as an environmental pollutant, has emerged as a potential candidate that holds clinical promise in mitigating IRI and preventing acute and chronic graft rejection when it is added to kidney preservation solutions at low concentrations or when administered to the kidney donor prior to kidney procurement and to the recipient or to the reperfusion circuit at the start and during reperfusion after renal graft preservation. Interestingly, dysregulated or abnormal endogenous production and metabolism of NO is associated with IRI in kidney transplantation. From experimental and clinical perspectives, this review presents endogenous enzymatic production of NO as well as its exogenous sources, and then discusses protective effects of constitutive nitric oxide synthase (NOS)-derived NO against IRI in kidney transplantation via several signaling pathways. The review also highlights a few isolated studies of renal graft protection by NO produced by inducible NOS.
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Affiliation(s)
- George J Dugbartey
- Department of Pharmacology and Toxicology, School of Pharmacy, College of Health Sciences, University of Ghana, Legon, Accra, Ghana; Accra College of Medicine, Magnolia St, JVX5+FX9, East Legon, Accra, Ghana.
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3
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Li L, Shen S, Bickler P, Jacobson MP, Wu LF, Altschuler SJ. Searching for molecular hypoxia sensors among oxygen-dependent enzymes. eLife 2023; 12:e87705. [PMID: 37494095 PMCID: PMC10371230 DOI: 10.7554/elife.87705] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 07/09/2023] [Indexed: 07/27/2023] Open
Abstract
The ability to sense and respond to changes in cellular oxygen levels is critical for aerobic organisms and requires a molecular oxygen sensor. The prototypical sensor is the oxygen-dependent enzyme PHD: hypoxia inhibits its ability to hydroxylate the transcription factor HIF, causing HIF to accumulate and trigger the classic HIF-dependent hypoxia response. A small handful of other oxygen sensors are known, all of which are oxygen-dependent enzymes. However, hundreds of oxygen-dependent enzymes exist among aerobic organisms, raising the possibility that additional sensors remain to be discovered. This review summarizes known and potential hypoxia sensors among human O2-dependent enzymes and highlights their possible roles in hypoxia-related adaptation and diseases.
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Affiliation(s)
- Li Li
- Department of Pharmaceutical Chemistry, University of California San Francisco, San FranciscoSan FranciscoUnited States
| | - Susan Shen
- Department of Pharmaceutical Chemistry, University of California San Francisco, San FranciscoSan FranciscoUnited States
- Department of Psychiatry, University of California, San FranciscoSan FranciscoUnited States
| | - Philip Bickler
- Hypoxia Research Laboratory, University of California San Francisco, San FranciscoSan FranciscoUnited States
- Center for Health Equity in Surgery and Anesthesia, University of California San Francisco, San FranciscoSan FranciscoUnited States
- Anesthesia and Perioperative Care, University of California San Francisco, San FranciscoSan FranciscoUnited States
| | - Matthew P Jacobson
- Department of Pharmaceutical Chemistry, University of California San Francisco, San FranciscoSan FranciscoUnited States
| | - Lani F Wu
- Department of Pharmaceutical Chemistry, University of California San Francisco, San FranciscoSan FranciscoUnited States
| | - Steven J Altschuler
- Department of Pharmaceutical Chemistry, University of California San Francisco, San FranciscoSan FranciscoUnited States
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4
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Zhang W, Liu B, Wang Y, Zhang H, He L, Wang P, Dong M. Mitochondrial dysfunction in pulmonary arterial hypertension. Front Physiol 2022; 13:1079989. [PMID: 36589421 PMCID: PMC9795033 DOI: 10.3389/fphys.2022.1079989] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 11/29/2022] [Indexed: 01/03/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is characterized by the increased pulmonary vascular resistance due to pulmonary vasoconstriction and vascular remodeling. PAH has high disability, high mortality and poor prognosis, which is becoming a more common global health issue. There is currently no drug that can permanently cure PAH patients. The pathogenesis of PAH is still not fully elucidated. However, the role of metabolic theory in the pathogenesis of PAH is becoming clearer, especially mitochondrial metabolism. With the deepening of mitochondrial researches in recent years, more and more studies have shown that the occurrence and development of PAH are closely related to mitochondrial dysfunction, including the tricarboxylic acid cycle, redox homeostasis, enhanced glycolysis, and increased reactive oxygen species production, calcium dysregulation, mitophagy, etc. This review will further elucidate the relationship between mitochondrial metabolism and pulmonary vasoconstriction and pulmonary vascular remodeling. It might be possible to explore more comprehensive and specific treatment strategies for PAH by understanding these mitochondrial metabolic mechanisms.
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Affiliation(s)
- Weiwei Zhang
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Bo Liu
- Department of Cardiovascular, Geratric Diseases Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Yazhou Wang
- Department of Cardiothoracic, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Hengli Zhang
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Lang He
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
| | - Pan Wang
- Department of Critical Care Medicine, The Traditional Chinese Medicine Hospital of Wenjiang District, Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
| | - Mingqing Dong
- Center for Medicine Research and Translation, Chengdu Fifth People’s Hospital (The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
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Petrykey K, Rezgui AM, Guern ML, Beaulieu P, St-Onge P, Drouin S, Bertout L, Wang F, Baedke JL, Yasui Y, Hudson MM, Raboisson MJ, Laverdière C, Sinnett D, Andelfinger GU, Krajinovic M. Genetic factors in treatment-related cardiovascular complications in survivors of childhood acute lymphoblastic leukemia. Pharmacogenomics 2021; 22:885-901. [PMID: 34505544 DOI: 10.2217/pgs-2021-0067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Cardiovascular disease represents one of the main causes of secondary morbidity and mortality in patients with childhood cancer. Patients & methods: To further address this issue, we analyzed cardiovascular complications in relation to common and rare genetic variants derived through whole-exome sequencing from childhood acute lymphoblastic leukemia survivors (PETALE cohort). Results: Significant associations were detected among common variants in the TTN gene, left ventricular ejection fraction (p ≤ 0.0005), and fractional shortening (p ≤ 0.001). Rare variants enrichment in the NOS1, ABCG2 and NOD2 was observed in relation to left ventricular ejection fraction, and in NOD2 and ZNF267 genes in relation to fractional shortening. Following stratification according to risk groups, the modulatory effect of rare variants was additionally found in the CBR1, ABCC5 and AKR1C3 genes. None of the associations was replicated in St-Jude Lifetime Cohort Study. Conclusion: Further studies are needed to confirm whether the described genetic markers may be useful in identifying patients at increased risk of these complications.
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Affiliation(s)
- Kateryna Petrykey
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada.,Department of Pharmacology & Physiology, Université de Montréal, QC, H3T 1J4, Canada
| | - Aziz M Rezgui
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Mathilde Le Guern
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Patrick Beaulieu
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Pascal St-Onge
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Simon Drouin
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Laurence Bertout
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada
| | - Fan Wang
- Department of Epidemiology & Cancer Control, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Jessica L Baedke
- Department of Epidemiology & Cancer Control, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Yutaka Yasui
- Department of Epidemiology & Cancer Control, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Melissa M Hudson
- Department of Epidemiology & Cancer Control, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.,Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Marie-Josée Raboisson
- Department of Pediatrics, Université de Montréal, QC, H3T 1C5, Canada.,Cardiology Unit, Sainte-Justine University Health Center (SJUHC), Montreal, QC, H3T 1C5, Canada
| | - Caroline Laverdière
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada.,Department of Pediatrics, Université de Montréal, QC, H3T 1C5, Canada
| | - Daniel Sinnett
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada.,Department of Pediatrics, Université de Montréal, QC, H3T 1C5, Canada
| | - Gregor U Andelfinger
- Department of Pediatrics, Université de Montréal, QC, H3T 1C5, Canada.,Fetomaternal and Neonatal Pathologies Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC, H3T 1C5, Canada
| | - Maja Krajinovic
- Immune Diseases and Cancer Research Axis, Sainte-Justine University Health Center (SJUHC), Montreal, QC H3T 1C5, Canada.,Department of Pharmacology & Physiology, Université de Montréal, QC, H3T 1J4, Canada.,Department of Pediatrics, Université de Montréal, QC, H3T 1C5, Canada
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6
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Rahman MS, Thomas P. Molecular Characterization and Expression of Cytochrome P450 Aromatase in Atlantic Croaker Brain: Regulation by Antioxidant Status and Nitric Oxide Synthase During Hypoxia Stress. Front Physiol 2021; 12:720200. [PMID: 34434121 PMCID: PMC8381199 DOI: 10.3389/fphys.2021.720200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 07/08/2021] [Indexed: 11/13/2022] Open
Abstract
We have previously shown that nitric oxide synthase (NOS, an enzyme) is significantly increased during hypoxic stress in Atlantic croaker brains and modulated by an antioxidant (AOX). However, the influence of NOS and AOX on cytochrome P450 aromatase (AROM, CYP19a1, an enzyme) activity on vertebrate brains during hypoxic stress is largely unknown. In this study, we characterized brain AROM (bAROM, CYP19a1b) cDNA in croaker and examined the interactive effects of hypoxia and a NOS-inhibitor or AOX on AROM activity. The amino acid sequence of croaker bAROM cDNA is highly homologous (76–80%) to other marine teleost bAROM cDNAs. Both real-time PCR and Northern blot analyses showed that bAROM transcript (size: ∼2.8 kb) is highly expressed in the preoptic-anterior hypothalamus (POAH). Hypoxia exposure (dissolved oxygen, DO: 1.7 mg/L for 4 weeks) caused significant decreases in hypothalamic AROM activity, bAROM mRNA and protein expressions. Hypothalamic AROM activity and mRNA levels were also decreased by pharmacological treatment with N-ethylmaleimide (NEM, an alkylating drug that modifies sulfhydryl groups) of fish exposed to normoxic (DO: ∼6.5 mg/L) conditions. On the other hand, treatments with Nω-nitro-L-arginine methyl ester (NAME, a competitive NOS-inhibitor) or vitamin-E (Vit-E, a powerful AOX) prevented the downregulation of hypothalamic AROM activity and mRNA levels in hypoxic fish. Moreover, NAME and Vit-E treatments also restored gonadal growth in hypoxic fish. Double-labeled immunohistochemistry results showed that AROM and NOS proteins are co-expressed with NADPH oxidase (generates superoxide anion) in the POAH. Collectively, these results suggest that the hypoxia-induced downregulation of AROM activity in teleost brains is influenced by neuronal NOS activity and AOX status. The present study provides, to the best of our knowledge, the first evidence of restoration of AROM levels in vertebrate brains by a competitive NOS-inhibitor and potent AOX during hypoxic stress.
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Affiliation(s)
- Md Saydur Rahman
- School of Earth, Environmental and Marine Sciences, University of Texas Rio Grande Valley, Brownsville, TX, United States.,Marine Science Institute, University of Texas at Austin, Port Aransas, TX, United States
| | - Peter Thomas
- Marine Science Institute, University of Texas at Austin, Port Aransas, TX, United States
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7
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Lázár Z, Mészáros M, Bikov A. The Nitric Oxide Pathway in Pulmonary Arterial Hypertension: Pathomechanism, Biomarkers and Drug Targets. Curr Med Chem 2021; 27:7168-7188. [PMID: 32442078 DOI: 10.2174/0929867327666200522215047] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 01/03/2020] [Accepted: 02/20/2020] [Indexed: 11/22/2022]
Abstract
The altered Nitric Oxide (NO) pathway in the pulmonary endothelium leads to increased vascular smooth muscle tone and vascular remodelling, and thus contributes to the development and progression of pulmonary arterial hypertension (PAH). The pulmonary NO signalling is abrogated by the decreased expression and dysfunction of the endothelial NO synthase (eNOS) and the accumulation of factors blocking eNOS functionality. The NO deficiency of the pulmonary vasculature can be assessed by detecting nitric oxide in the exhaled breath or measuring the degradation products of NO (nitrite, nitrate, S-nitrosothiol) in blood or urine. These non-invasive biomarkers might show the potential to correlate with changes in pulmonary haemodynamics and predict response to therapies. Current pharmacological therapies aim to stimulate pulmonary NO signalling by suppressing the degradation of NO (phosphodiesterase- 5 inhibitors) or increasing the formation of the endothelial cyclic guanosine monophosphate, which mediates the downstream effects of the pathway (soluble guanylate cyclase sensitizers). Recent data support that nitrite compounds and dietary supplements rich in nitrate might increase pulmonary NO availability and lessen vascular resistance. This review summarizes current knowledge on the involvement of the NO pathway in the pathomechanism of PAH, explores novel and easy-to-detect biomarkers of the pulmonary NO.
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Affiliation(s)
- Zsófia Lázár
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Martina Mészáros
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Andras Bikov
- Department of Pulmonology, Semmelweis University, Budapest, Hungary,Manchester University NHS Foundation Trust, Manchester, United Kingdom
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8
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Zaric BL, Radovanovic JN, Gluvic Z, Stewart AJ, Essack M, Motwalli O, Gojobori T, Isenovic ER. Atherosclerosis Linked to Aberrant Amino Acid Metabolism and Immunosuppressive Amino Acid Catabolizing Enzymes. Front Immunol 2020; 11:551758. [PMID: 33117340 PMCID: PMC7549398 DOI: 10.3389/fimmu.2020.551758] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 08/25/2020] [Indexed: 02/05/2023] Open
Abstract
Cardiovascular disease is the leading global health concern and responsible for more deaths worldwide than any other type of disorder. Atherosclerosis is a chronic inflammatory disease in the arterial wall, which underpins several types of cardiovascular disease. It has emerged that a strong relationship exists between alterations in amino acid (AA) metabolism and the development of atherosclerosis. Recent studies have reported positive correlations between levels of branched-chain amino acids (BCAAs) such as leucine, valine, and isoleucine in plasma and the occurrence of metabolic disturbances. Elevated serum levels of BCAAs indicate a high cardiometabolic risk. Thus, BCAAs may also impact atherosclerosis prevention and offer a novel therapeutic strategy for specific individuals at risk of coronary events. The metabolism of AAs, such as L-arginine, homoarginine, and L-tryptophan, is recognized as a critical regulator of vascular homeostasis. Dietary intake of homoarginine, taurine, and glycine can improve atherosclerosis by endothelium remodeling. Available data also suggest that the regulation of AA metabolism by indoleamine 2,3-dioxygenase (IDO) and arginases 1 and 2 are mediated through various immunological signals and that immunosuppressive AA metabolizing enzymes are promising therapeutic targets against atherosclerosis. Further clinical studies and basic studies that make use of animal models are required. Here we review recent data examining links between AA metabolism and the development of atherosclerosis.
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Affiliation(s)
- Bozidarka L. Zaric
- Department of Radiobiology and Molecular Genetics, “VINČA” Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Jelena N. Radovanovic
- Department of Radiobiology and Molecular Genetics, “VINČA” Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Zoran Gluvic
- Department of Endocrinology and Diabetes, Faculty of Medicine, University Clinical-Hospital Centre Zemun-Belgrade, University of Belgrade, Belgrade, Serbia
| | - Alan J. Stewart
- School of Medicine, University of St Andrews, St Andrews, United Kingdom
| | - Magbubah Essack
- Computer, Electrical and Mathematical Sciences and Engineering Division (CEMSE), Computational Bioscience Research Center, Computer (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Olaa Motwalli
- College of Computing and Informatics, Saudi Electronic University (SEU), Medina, Saudi Arabia
| | - Takashi Gojobori
- Computer, Electrical and Mathematical Sciences and Engineering Division (CEMSE), Computational Bioscience Research Center, Computer (CBRC), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
- Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Esma R. Isenovic
- Department of Radiobiology and Molecular Genetics, “VINČA” Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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9
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Hypoxia: Turning vessels into vassals of cancer immunotolerance. Cancer Lett 2020; 487:74-84. [PMID: 32470491 DOI: 10.1016/j.canlet.2020.05.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 04/27/2020] [Accepted: 05/12/2020] [Indexed: 12/12/2022]
Abstract
Hypoxia is a universal feature of solid cancers caused by a mismatch between cellular oxygen supply and consumption. To meet the increased demand for oxygen, hypoxic cancer cells (CCs) induce a multifaceted process known as angiogenesis, wherein new vessels are formed by the sprouting of pre-existing ones. In addition to providing oxygen for growth and an exit route for dissemination, angiogenic vessels and factors are co-opted by CCs to enable the generation of an immunotolerant, hypoxic tumor microenvironment, leading to therapeutic failure and mortality. In this review, we discuss how hypoxia-inducible factors (HIFs), the mechanistic target of rapamycin (mTOR), and the unfolded protein response (UPR) control angiogenic factors serving both vascular and immunomodulatory functions in the tumor microenvironment. Possible therapeutic strategies, wherein targeting oxygen sensing might enhance anti-angiogenic and immunologically-mediated anti-cancer responses, are suggested.
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10
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Bergmann A, Schilling T, Perchiazzi G, Kretzschmar M, Hedenstierna G, Hachenberg T, Larsson A. Effect of remote ischemic preconditioning on exhaled nitric oxide concentration in piglets during and after one-lung ventilation. Respir Physiol Neurobiol 2020; 276:103426. [DOI: 10.1016/j.resp.2020.103426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/26/2020] [Accepted: 02/24/2020] [Indexed: 12/19/2022]
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11
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Abstract
Chronic obstructive pulmonary disease (COPD) is a common and progressive disorder
which is characterised by pathological abnormalities driven by chronic airway inflammation. The
assessment of airway inflammation in routine clinical practice in COPD is limited to surrogate blood
markers. Fractional exhaled nitric oxide (FENO) is a marker of eosinophilic airway inflammation in
asthma, and it can predict steroid responsiveness and help tailor corticosteroid treatment. The clinical
value of FENO in COPD is less evident, but some studies suggest that it may be a marker of the
eosinophilic endotype. More importantly, mathematical methods allow investigation of the
alveolar/small airway production of NO which potentially better reflects inflammatory changes in
anatomical sites, most affected by COPD. This review summarises the pathophysiological role of
nitric oxide in COPD, explains the methodology of its measurement in exhaled air and discusses
clinical findings of FENO in COPD.
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Affiliation(s)
- Andras Bikov
- NIHR Manchester Clinical Research Facility, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Martina Meszaros
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Zsofia Lazar
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
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12
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Lambden S. Bench to bedside review: therapeutic modulation of nitric oxide in sepsis-an update. Intensive Care Med Exp 2019; 7:64. [PMID: 31792745 PMCID: PMC6888802 DOI: 10.1186/s40635-019-0274-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 10/11/2019] [Indexed: 12/17/2022] Open
Abstract
Nitric oxide is a signalling molecule with an extensive range of functions in both health and disease. Discovered in the 1980s through work that earned the Nobel prize, nitric oxide is an essential factor in regulating cardiovascular, immune, neurological and haematological function in normal homeostasis and in response to infection. Early work implicated exaggerated nitric oxide synthesis as a potentially important driver of septic shock; however, attempts to modulate production through global inhibition of nitric oxide synthase were associated with increased mortality. Subsequent work has shown that regulation of nitric oxide production is determined by numerous factors including substrate and co-factor availability and expression of endogenous regulators. In sepsis, nitric oxide synthesis is dysregulated with exaggerated production leading to cardiovascular dysfunction, bioenergetic failure and cellular toxicity whilst at the same time impaired microvascular function may be driven in part by reduced nitric oxide synthesis by the endothelium. This bench to bedside review summarises our current understanding of the ways in which nitric oxide production is regulated on a tissue and cellular level before discussing progress in translating these observations into novel therapeutic strategies for patients with sepsis.
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Affiliation(s)
- Simon Lambden
- Department of Medicine, Addenbrooke's Hospital, Cambridge University, 5th Floor, Cambridge, CB20QQ, UK.
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13
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Stuart JA, Aibueku O, Bagshaw O, Moradi F. Hypoxia inducible factors as mediators of reactive oxygen/nitrogen species homeostasis in physiological normoxia. Med Hypotheses 2019; 129:109249. [DOI: 10.1016/j.mehy.2019.109249] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 04/15/2019] [Accepted: 05/26/2019] [Indexed: 12/12/2022]
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14
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Schito L. Hypoxia-Dependent Angiogenesis and Lymphangiogenesis in Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1136:71-85. [PMID: 31201717 DOI: 10.1007/978-3-030-12734-3_5] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hypoxia (low O2) is a ubiquitous feature of solid cancers, arising as a mismatch between cellular O2 supply and consumption. Hypoxia is associated to metastatic disease and mortality owing to its ability to stimulate the formation of blood (angiogenesis) and lymphatic vessels (lymphangiogenesis), thereby allowing cancer cells to escape the unfavorable tumor microenvironment and disseminate into secondary sites. This review outlines molecular mechanisms by which intratumoral hypoxia regulates the expression of motogenic and mitogenic factors that induce angiogenesis and lymphangiogenesis, whilst discussing their implications for metastatic cancers.
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Affiliation(s)
- Luana Schito
- Biological Sciences Platform, Sunnybrook Research Institute, University of Toronto, Toronto, ON, Canada.
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15
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Nagahisa H, Miyata H. Influence of hypoxic stimulation on angiogenesis and satellite cells in mouse skeletal muscle. PLoS One 2018; 13:e0207040. [PMID: 30408093 PMCID: PMC6224099 DOI: 10.1371/journal.pone.0207040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 10/23/2018] [Indexed: 01/22/2023] Open
Abstract
We clarified in our previous study that hypoxic training promotes angiogenesis in skeletal muscle, but the mechanism of angiogenesis in skeletal muscle remains unknown. In this study, we investigated the influence of differences in hypoxia exposure on angiogenesis in skeletal muscles at differing ages and metabolic characteristics at which the production of reactive oxygen species and nitric oxide may differ. Ten-week-old (young) and 20-month-old (old) mice were separated into control (N), continuous hypoxia (H), and intermittent hypoxia (IH) groups. The H group was exposed to 16% O2 hypoxia for 5 days and the IH group was exposed to 16% O2 hypoxia at one-hour intervals during the light period for 5 days. After completion of hypoxia exposure, the soleus and gastrocnemius muscles were immediately excised, and mRNA expression of angiogenesis- and satellite cell-related genes was investigated using real-time RT-PCR. In addition, muscle fiber type composition, muscle fiber area, number of satellite cells, and capillary density were measured immunohistochemically. In the young soleus muscle, the muscle fiber area was decreased in the H group, and mRNA expression of satellite cell activation-related MyoD, MHCe, and BDNF was significantly increased. On the other hand, in the old soleus muscle, nNOS and VEGF-A mRNA expression, and the capillary density were significantly increased in the H group. In the superficial portion of the gastrocnemius, mRNA expression of FGF2, an angiogenic factor secreted by satellite cells, was significantly increased in the young IH group. In addition, a positive correlation between VEGF-A mRNA expression and nNOS mRNA expression in the soleus muscle and eNOS mRNA expression in the superficial portion of the gastrocnemius was noted. These data demonstrated that age, hypoxia exposure method and muscle metabolic characteristics are related, which results in significant differences in angiogenesis.
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Affiliation(s)
- Hiroshi Nagahisa
- Biological Sciences, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
| | - Hirofumi Miyata
- Biological Sciences, Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi, Japan
- * E-mail:
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16
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Katsui S, Inoue Y, Igari K, Toyofuku T, Kudo T, Uetake H. Novel assessment tool based on laser speckle contrast imaging to diagnose severe ischemia in the lower limb for patients with peripheral arterial disease. Lasers Surg Med 2017. [PMID: 28370223 DOI: 10.1002/lsm.v49.7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
OBJECTIVE We propose a new assessment tool to diagnose severe ischemia of the lower limb in peripheral arterial disease, using laser speckle contrast imaging to evaluate heating-induced microcirculatory fluctuations in the proximal and distal sites of the dorsal foot. STUDY DESIGN A cross-sectional study. METHODS We recorded the slope describing the behavior of perfusion values (decrease or plateau) following the initial, heating-induced increase in perfusion in 63 feet of patients with clinical signs of peripheral arterial disease. RESULTS The plateau and decrease groups were defined as having perfusion slopes of <0.20 and ≥0.20 PU/min, respectively. Transcutaneous oxygen tension was significantly lower (P < 0.001) in the plateau than in the decrease group (8 vs. 45 mmHg), indicating more severe ischemia. The laser speckle contrast imaging thermal load test discriminated transcutaneous oxygen tension <30 mmHg with good sensitivity (78.7%) and specificity (96.2%), and an area under the curve of 0.908. CONCLUSIONS Both transcutaneous oxygen tension and the laser speckle contrast imaging thermal load test are useful in diagnosing severe ischemia in the foot. Lasers Surg. Med. 49:645-651, 2017. © 2017. The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Sotaro Katsui
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshinori Inoue
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kimihiro Igari
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takahiro Toyofuku
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshifumi Kudo
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hiroyuki Uetake
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
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17
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Chachlaki K, Garthwaite J, Prevot V. The gentle art of saying NO: how nitric oxide gets things done in the hypothalamus. Nat Rev Endocrinol 2017. [PMID: 28621341 DOI: 10.1038/nrendo.2017.69] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The chemical signalling molecule nitric oxide (NO), which freely diffuses through aqueous and lipid environments, subserves an array of functions in the mammalian central nervous system, such as the regulation of synaptic plasticity, blood flow and neurohormone secretion. In this Review, we consider the cellular and molecular mechanisms by which NO evokes short-term and long-term changes in neuronal activity. We also highlight recent studies showing that discrete populations of neurons that synthesize NO in the hypothalamus constitute integrative systems that support life by relaying metabolic and gonadal signals to the neuroendocrine brain, and thus gate the onset of puberty and adult fertility. The putative involvement and therapeutic potential of NO in the pathophysiology of brain diseases, for which hormonal imbalances during postnatal development could be risk factors, is also discussed.
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Affiliation(s)
- Konstantina Chachlaki
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, UMR-S 1172, 1 place de Verdun, F-59000 Lille, France
- University of Lille, University Hospital Federations (FHU) 1,000 days for Health, School of Medicine, 1 place de Verdun, F-59000 Lille, France
| | - John Garthwaite
- The Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, UK
| | - Vincent Prevot
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, UMR-S 1172, 1 place de Verdun, F-59000 Lille, France
- University of Lille, University Hospital Federations (FHU) 1,000 days for Health, School of Medicine, 1 place de Verdun, F-59000 Lille, France
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18
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Association Between NOS1 Gene Polymorphisms and Schizophrenia in Asian and Caucasian Populations: A Meta-Analysis. Neuromolecular Med 2017; 19:452-461. [PMID: 28795310 DOI: 10.1007/s12017-017-8460-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 08/01/2017] [Indexed: 01/11/2023]
Abstract
Schizophrenia is a complex psychiatric disorder characterized by memory impairments with delusions and hallucinations. Several investigations have focused on determining the association between NOS1 (nitric oxide synthase-1) polymorphisms and risk of schizophrenia (SZ). However, the association of rs2682826, rs3782206, rs499776, rs3782219, rs41279104, rs3782221, rs1879417, rs4767540, rs561712, and rs6490121 polymorphisms with schizophrenia remains inconclusive. We performed a systematic meta-analysis for each polymorphism to determine its association with SZ by calculating their pooled odds ratio and 95% confidence intervals. The heterogeneity between studies was evaluated using Cochran's Q test to adopt random effects or fixed effects model. Based on our analysis, the rs3782206 polymorphism showed a strongest association with schizophrenia in allelic OR 1.15 (95% CI [1.05-1.25]), homozygote OR 1.35 (95% CI [1.09-1.66]), dominant OR 1.16 (95% CI [1.04-1.29]), and recessive OR 1.29 (95% CI [1.05-1.58]) models in Asian population. Similarly, in Caucasian population, the rs499776 polymorphism attributes risk association in homozygote OR 0.70 (95% CI [0.50-0.98]), dominant OR 3.57 (95% CI [2.34-5.27]), and recessive models OR 0.68 (95% CI [0.50-0.93]) with schizophrenia. Further, the sensitivity analysis was carried out based on leave-one-out method to confirm the reliability of the analysis. Overall, our meta-analysis demonstrates the significance of NOS1 genetic variants that are functionally associated with cognitive and neuropsychiatric symptoms of schizophrenia.
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19
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Katsui S, Inoue Y, Igari K, Toyofuku T, Kudo T, Uetake H. Novel assessment tool based on laser speckle contrast imaging to diagnose severe ischemia in the lower limb for patients with peripheral arterial disease. Lasers Surg Med 2017; 49:645-651. [PMID: 28370223 PMCID: PMC5573943 DOI: 10.1002/lsm.22669] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2017] [Indexed: 12/31/2022]
Abstract
Objective We propose a new assessment tool to diagnose severe ischemia of the lower limb in peripheral arterial disease, using laser speckle contrast imaging to evaluate heating‐induced microcirculatory fluctuations in the proximal and distal sites of the dorsal foot. Study Design A cross‐sectional study. Methods We recorded the slope describing the behavior of perfusion values (decrease or plateau) following the initial, heating‐induced increase in perfusion in 63 feet of patients with clinical signs of peripheral arterial disease. Results The plateau and decrease groups were defined as having perfusion slopes of <0.20 and ≥0.20 PU/min, respectively. Transcutaneous oxygen tension was significantly lower (P < 0.001) in the plateau than in the decrease group (8 vs. 45 mmHg), indicating more severe ischemia. The laser speckle contrast imaging thermal load test discriminated transcutaneous oxygen tension <30 mmHg with good sensitivity (78.7%) and specificity (96.2%), and an area under the curve of 0.908. Conclusions Both transcutaneous oxygen tension and the laser speckle contrast imaging thermal load test are useful in diagnosing severe ischemia in the foot. Lasers Surg. Med. 49:645–651, 2017. © 2017. The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Sotaro Katsui
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshinori Inoue
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Kimihiro Igari
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takahiro Toyofuku
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshifumi Kudo
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hiroyuki Uetake
- Department of Surgical Specialties, Tokyo Medical and Dental University, Tokyo, Japan
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20
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Zhang YH. Neuronal nitric oxide synthase in hypertension - an update. Clin Hypertens 2016; 22:20. [PMID: 27822383 PMCID: PMC5093926 DOI: 10.1186/s40885-016-0055-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/19/2016] [Indexed: 02/07/2023] Open
Abstract
Hypertension is a prevalent condition worldwide and is the key risk factor for fatal cardiovascular complications, such as stroke, sudden cardiac death and heart failure. Reduced bioavailability of nitric oxide (NO) in the endothelium is an important precursor for impaired vasodilation and hypertension. In the heart, NO deficiency deteriorates the adverse consequences of pressure-overload and causes cardiac hypertrophy, fibrosis and myocardial infarction which lead to fatal heart failure and sudden cardiac death. Recent consensus is that both endothelial and neuronal nitric oxide synthases (eNOS or NOS3 and nNOS or NOS1) are the constitutive sources of NO in the myocardium. Between the two, nNOS is the predominant isoform of NOS that controls intracellular Ca2+ homeostasis, myocyte contraction, relaxation and signaling pathways including nitroso-redox balance. Notably, our recent research indicates that cardiac eNOS protein is reduced but nNOS protein expression and activity are increased in hypertension. Furthermore, nNOS is induced by the interplay between angiotensin II (Ang II) type 1 receptor (AT1R) and Ang II type 2 receptor (AT2R), mediated by NADPH oxidase and reactive oxygen species (ROS)-dependent eNOS activity in cardiac myocytes. nNOS, in turn, protects the heart from pathogenesis via positive lusitropy in hypertension. Soluble guanylate cyclase (sGC)-cGMP/PKG-dependent phosphorylation of myofilament proteins are novel targets of nNOS in hypertensive myocardium. In this short review, we will endeavor to overview new findings of the up-stream and downstream regulation of cardiac nNOS in hypertension, shed light on the underlying mechanisms which may be of therapeutic value in hypertensive cardiomyopathy.
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Affiliation(s)
- Yin Hua Zhang
- Department of Physiology & Biomedical Sciences, Ischemic/Hypoxic Disease Institute, Seoul National University, College of Medicine, 103 Dae Hak Ro, Chong No Gu, 110-799 Seoul Korea ; Yanbian University Hospital, Yanji, Jilin Province 133000 China ; Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
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21
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Torgerson DG, Giri T, Druley TE, Zheng J, Huntsman S, Seibold MA, Young AL, Schweiger T, Yin-Declue H, Sajol GD, Schechtman KB, Hernandez RD, Randolph AG, Bacharier LB, Castro M. Pooled Sequencing of Candidate Genes Implicates Rare Variants in the Development of Asthma Following Severe RSV Bronchiolitis in Infancy. PLoS One 2015; 10:e0142649. [PMID: 26587832 PMCID: PMC4654486 DOI: 10.1371/journal.pone.0142649] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 02/06/2015] [Indexed: 12/17/2022] Open
Abstract
Severe infection with respiratory syncytial virus (RSV) during infancy is strongly associated with the development of asthma. To identify genetic variation that contributes to asthma following severe RSV bronchiolitis during infancy, we sequenced the coding exons of 131 asthma candidate genes in 182 European and African American children with severe RSV bronchiolitis in infancy using anonymous pools for variant discovery, and then directly genotyped a set of 190 nonsynonymous variants. Association testing was performed for physician-diagnosed asthma before the 7th birthday (asthma) using genotypes from 6,500 individuals from the Exome Sequencing Project (ESP) as controls to gain statistical power. In addition, among patients with severe RSV bronchiolitis during infancy, we examined genetic associations with asthma, active asthma, persistent wheeze, and bronchial hyperreactivity (methacholine PC20) at age 6 years. We identified four rare nonsynonymous variants that were significantly associated with asthma following severe RSV bronchiolitis, including single variants in ADRB2, FLG and NCAM1 in European Americans (p = 4.6x10-4, 1.9x10-13 and 5.0x10-5, respectively), and NOS1 in African Americans (p = 2.3x10-11). One of the variants was a highly functional nonsynonymous variant in ADRB2 (rs1800888), which was also nominally associated with asthma (p = 0.027) and active asthma (p = 0.013) among European Americans with severe RSV bronchiolitis without including the ESP. Our results suggest that rare nonsynonymous variants contribute to the development of asthma following severe RSV bronchiolitis in infancy, notably in ADRB2. Additional studies are required to explore the role of rare variants in the etiology of asthma and asthma-related traits following severe RSV bronchiolitis.
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Affiliation(s)
- Dara G. Torgerson
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Tusar Giri
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Todd E. Druley
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jie Zheng
- Department of Biostatistics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Scott Huntsman
- Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| | - Max A. Seibold
- Integrated Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Andrew L. Young
- Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Toni Schweiger
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Huiqing Yin-Declue
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Geneline D. Sajol
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Kenneth B Schechtman
- Department of Biostatistics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Ryan D. Hernandez
- Department of Bioengineering and Therapeutic Sciences, Institute of Human Genetics, and California Institute of Quantitative Biosciences (QB3), University of California San Francisco, San Francisco, California, United States of America
| | - Adrienne G. Randolph
- Department of Anesthesiology, Boston Children’s Hospital, Boston, Massachusetts, United States of America
| | - Leonard B. Bacharier
- Department of Pediatrics, Washington University School of Medicine and St. Louis Children’s Hospital, St. Louis, Missouri, United States of America
| | - Mario Castro
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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22
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Nara A, Nagai H, Shintani-Ishida K, Ogura S, Shimosawa T, Kuwahira I, Shirai M, Yoshida KI. Pulmonary arterial hypertension in rats due to age-related arginase activation in intermittent hypoxia. Am J Respir Cell Mol Biol 2015; 53:184-92. [PMID: 25490411 DOI: 10.1165/rcmb.2014-0163oc] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is prevalent in patients with obstructive sleep apnea syndrome (OSAS). Aging induces arginase activation and reduces nitric oxide (NO) production in the arteries. Intermittent hypoxia (IH), conferred by cycles of brief hypoxia and normoxia, contributes to OSAS pathogenesis. Here, we studied the role of arginase and aging in the pathogenesis of PAH in adult (9-mo-old) and young (2-mo-old) male Sprague-Dawley rats subjected to IH or normoxia for 4 weeks and analyzed them with a pressure-volume catheter inserted into the right ventricle (RV) and by pulsed Doppler echocardiography. Western blot analysis was conducted on arginase, NO synthase isoforms, and nitrotyrosine. IH induced PAH, as shown by increased RV systolic pressure and RV hypertrophy, in adult rats but not in young rats. IH increased expression levels of arginase I and II proteins in the adult rats. IH also increased arginase I expression in the pulmonary artery endothelium and arginase II in the pulmonary artery adventitia. Furthermore, IH reduced pulmonary levels of nitrate and nitrite but increased nitrotyrosine levels in adult rats. An arginase inhibitor (N(ω)-hydroxy-nor-1-arginine) prevented IH-induced PAH and normalized nitrite and nitrate levels in adult rats. IH induced arginase up-regulation and PAH in adult rats, but not in young rats, through reduced NO production. Our findings suggest that arginase inhibition prevents or reverses PAH.
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Affiliation(s)
- Akina Nara
- 1 Department of Forensic Medicine, Graduate School of Medicine and
| | - Hisashi Nagai
- 1 Department of Forensic Medicine, Graduate School of Medicine and
| | | | - Sayoko Ogura
- 1 Department of Forensic Medicine, Graduate School of Medicine and.,2 Division of Laboratory Medicine, Department of Pathology and Microbiology, Faculty of Medicine, Nihon University School of Medicine, Tokyo, Japan
| | - Tatsuo Shimosawa
- 3 Department of Clinical Laboratory, Faculty of Medicine, the University of Tokyo, Tokyo, Japan
| | - Ichiro Kuwahira
- 4 Department of Respiratory Medicine, Tokai University School of Medicine, Kanagawa, Japan; and
| | - Mikiyasu Shirai
- 5 Department of Cardiac Physiology, National Cerebral & Cardiovascular Center, Osaka, Japan
| | - Ken-ichi Yoshida
- 1 Department of Forensic Medicine, Graduate School of Medicine and
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23
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Li G, Zhao Y, Li Y, Lu J. Up-Regulation of Neuronal Nitric Oxide Synthase Expression by Cobalt Chloride Through a HIF-1α Mechanism in Neuroblastoma Cells. Neuromolecular Med 2015; 17:443-53. [PMID: 26458913 DOI: 10.1007/s12017-015-8373-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/03/2015] [Indexed: 10/22/2022]
Abstract
Nitric oxide (NO) plays a dual role in response to neural hypoxia. NO is synthesized by three isoforms of nitric oxide synthase (NOS), among which the neuronal NOS (nNOS) is predominant in the nervous system. Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that is induced under hypoxic conditions, but its correlation with nNOS remains unclear. In the present study, we aimed at clarifying the regulation pattern of the nNOS expression in response to cobalt chloride (CoCl2), a widely used chemical mimic of hypoxia, and the role of HIF-1α in this process in neuroblastoma cells. We found CoCl2 evidently increased the nNOS expression and NO production in human neuroblastoma SK-N-SH cells, but the effect of CoCl2 on NO was partially abrogated by 7-nitroindazole, a selective inhibitor for nNOS. Importantly, we identified a hypoxia response element (HRE) within the nNOS promoter, to which HIF-1α may bind, and CoCl2 greatly enhanced the HIF-1α expression and its binding to the HRE. Meanwhile, we demonstrated that this HRE was functionally important for the activation of the nNOS transcription, and CoCl2 increased the transcriptional activity of the nNOS promoter through this HRE. Taken together, our study shows that CoCl2 may induce the nNOS expression and NO production through a HIF-1α mechanism in neuroblastoma cells, which may provide a potential target for the treatment of neurological hypoxic disorders caused by NO dysregulation.
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Affiliation(s)
- Guangyu Li
- Department of Neurosurgery, The First Affiliated Hospital, China Medical University, No. 155, Nanjing Street, Heping District, Shenyang, 110001, People's Republic of China.
| | - Yanyan Zhao
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China.
| | - Yinghui Li
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China
| | - Jingyu Lu
- Department of Medical Genetics, College of Basic Medical Science, China Medical University, No. 92, Bei Er Road, Heping District, Shenyang, 110001, People's Republic of China
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24
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Duan L, Lei H, Zhang Y, Wan B, Chang J, Feng Q, Huang W. Calcitonin Gene-Related Peptide Improves Hypoxia-Induced Inflammation and Apoptosis via Nitric Oxide in H9c2 Cardiomyoblast Cells. Cardiology 2015; 133:44-53. [PMID: 26430901 DOI: 10.1159/000439123] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 07/31/2015] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The aim of this work was to investigate whether calcitonin gene-related peptide (CGRP) plays a protective role in cardiomyocytes against hypoxia-induced inflammation and apoptosis via an NO-mediated pathway. METHODS H9c2 cardiac cells were exposed to hypoxia for 2 h to establish a model of myocardial hypoxic-ischemic injury. The cells were pretreated with either CGRP or nitric oxide synthase (NOS) inhibitor (L-NAME) before being exposed to hypoxia for 30 min. Cell viability was analyzed using a cell counter kit 8 (CCK-8). The levels of IL-6 and TNF-α were determined by the corresponding enzyme-linked immunosorbent assay. The expression levels of several apoptosis proteins (p53, caspase-3, cytochrome C) and NOS were detected by Western blot assays. An NO kit was used to evaluate the production of NO. RESULTS Pretreatment of H9c2 cardiac cells with CGRP for 30 min prior to exposure to hypoxia markedly improved cell viability (83.57 ± 3.21 vs. 62.83 ± 8.30%, p < 0.001); the same effect was observed following pretreatment with the NOS inhibitor L-NAME (89.34 ± 5.95 vs. 75.01 ± 5.61%, p < 0.01). Pretreatment with CGRP also significantly attenuated the inflammatory responses induced by hypoxia, as evidenced by decreases of the levels of both IL-6 (193.21 ± 13.54 vs. 293.38 ± 56.49%, p < 0.001) and TNF-α (207.71 ± 44.27 vs. 281.46 ± 64.88%, p < 0.001). Additionally, CGRP significantly decreased the hypoxia-induced overexpression of the apoptotic proteins (p53: 0.27 ± 0.10 vs. 0.87 ± 0.30, p < 0.001; caspase-3: 0.65 ± 0.15 vs. 0.98 ± 0.26, p < 0.001; cytochrome C: 1.51 ± 0.39 vs. 2.80 ± 0.69, p < 0.001) and enhanced the expression of both endothelial NOS (eNOS; 0.59 ± 0.24 vs. 0.37 ± 0.14, p < 0.05) and phosphorylated eNOS (0.60 ± 0.13 vs. 0.40 ± 0.07, p < 0.05). Furthermore, the application of both L-NAME and CGRP attenuated the hypoxia-induced expression of inducible NOS (iNOS; p < 0.05) and enhanced a hypoxia-mediated decrease in NO (p < 0.01). Interestingly, the expression levels of cell apoptosis (p < 0.05), iNOS and eNOS (p < 0.05) were decreased with L-NAME and CGRP cotreatment following 2 h of acute hypoxia, but the apoptotic factors (p < 0.05) were increased compared with only CGRP pretreatment. CONCLUSION CGRP protects cardiomyocytes from hypoxia-induced inflammation and apoptosis by modulating NO production.
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Affiliation(s)
- Lixiao Duan
- Cardiovascular Laboratory, Department of Cardiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, PR China
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Vascular nitric oxide: Beyond eNOS. J Pharmacol Sci 2015; 129:83-94. [PMID: 26499181 DOI: 10.1016/j.jphs.2015.09.002] [Citation(s) in RCA: 477] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 09/11/2015] [Accepted: 09/16/2015] [Indexed: 02/06/2023] Open
Abstract
As the first discovered gaseous signaling molecule, nitric oxide (NO) affects a number of cellular processes, including those involving vascular cells. This brief review summarizes the contribution of NO to the regulation of vascular tone and its sources in the blood vessel wall. NO regulates the degree of contraction of vascular smooth muscle cells mainly by stimulating soluble guanylyl cyclase (sGC) to produce cyclic guanosine monophosphate (cGMP), although cGMP-independent signaling [S-nitrosylation of target proteins, activation of sarco/endoplasmic reticulum calcium ATPase (SERCA) or production of cyclic inosine monophosphate (cIMP)] also can be involved. In the blood vessel wall, NO is produced mainly from l-arginine by the enzyme endothelial nitric oxide synthase (eNOS) but it can also be released non-enzymatically from S-nitrosothiols or from nitrate/nitrite. Dysfunction in the production and/or the bioavailability of NO characterizes endothelial dysfunction, which is associated with cardiovascular diseases such as hypertension and atherosclerosis.
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Rahman MS, Thomas P. Molecular characterization and hypoxia-induced upregulation of neuronal nitric oxide synthase in Atlantic croaker: Reversal by antioxidant and estrogen treatments. Comp Biochem Physiol A Mol Integr Physiol 2015; 185:91-106. [DOI: 10.1016/j.cbpa.2015.03.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 03/20/2015] [Accepted: 03/25/2015] [Indexed: 01/27/2023]
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Tsui AKY, Marsden PA, Mazer CD, Sled JG, Lee KM, Henkelman RM, Cahill LS, Zhou YQ, Chan N, Liu E, Hare GMT. Differential HIF and NOS responses to acute anemia: defining organ-specific hemoglobin thresholds for tissue hypoxia. Am J Physiol Regul Integr Comp Physiol 2014; 307:R13-25. [DOI: 10.1152/ajpregu.00411.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Tissue hypoxia likely contributes to anemia-induced organ injury and mortality. Severe anemia activates hypoxia-inducible factor (HIF) signaling by hypoxic- and neuronal nitric oxide (NO) synthase- (nNOS) dependent mechanisms. However, organ-specific hemoglobin (Hb) thresholds for increased HIF expression have not been defined. To assess organ-specific Hb thresholds for tissue hypoxia, HIF-α (oxygen-dependent degradation domain, ODD) luciferase mice were hemodiluted to mild, moderate, or severe anemia corresponding to Hb levels of 90, 70, and 50 g/l, respectively. HIF luciferase reporter activity, HIF protein, and HIF-dependent RNA levels were assessed. In the brain, HIF-1α was paradoxically decreased at mild anemia, returned to baseline at moderate anemia, and then increased at severe anemia. Brain HIF-2α remained unchanged at all Hb levels. Both kidney HIF-1α and HIF-2α increased earlier (Hb ∼70–90 g/l) in response to anemia. Liver also exhibited an early HIF-α response. Carotid blood flow was increased early (Hb ∼70, g/l), but renal blood flow remained relatively constant, only increased at Hb of 50 g/l. Anemia increased nNOS (brain and kidney) and endothelia NOS (eNOS) (kidney) levels. Whereas anemia-induced increases in brain HIFα were nNOS-dependent, our current data demonstrate that increased renal HIFα was nNOS independent. HIF-dependent RNA levels increased linearly (∼10-fold) in the brain. However, renal HIF-RNA responses (MCT4, EPO) increased exponentially (∼100-fold). Plasma EPO levels increased near Hb threshold of 90 g/l, suggesting that the EPO response is sensitive. Collectively, these observations suggest that each organ expresses a different threshold for cellular HIF/NOS hypoxia responses. This knowledge may help define the mechanism(s) by which the brain and kidney maintain oxygen homeostasis during anemia.
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Affiliation(s)
- Albert K. Y. Tsui
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Philip A. Marsden
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Medicine, Division of Nephrology, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - C. David Mazer
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - John G. Sled
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Keith M. Lee
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
| | - R. Mark Henkelman
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lindsay S. Cahill
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yu-Qing Zhou
- Department of Medical Biophysics, University of Toronto, Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Neville Chan
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
| | - Elaine Liu
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
| | - Gregory M. T. Hare
- Department of Anesthesia, St. Michael's Hospital, University of Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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Breton CV, Park C, Siegmund K, Gauderman WJ, Whitfield-Maxwell L, Hodis HN, Avol E, Gilliland FD. NOS1 methylation and carotid artery intima-media thickness in children. ACTA ACUST UNITED AC 2014; 7:116-22. [PMID: 24622112 DOI: 10.1161/circgenetics.113.000320] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Nitric oxide (NO) plays an important role in cardiovascular health by maintaining and regulating vascular tone and blood flow. Epigenetic regulation of NO synthase (NOS), the genes responsible for NO production, may affect cardiovascular disease, including the development of atherosclerosis in children. METHODS AND RESULTS We measured percentage DNA methylation using bisulfite conversion and pyrosequencing assays on DNA from buccal cells provided by 377 participants of the Children's Health Study on whom carotid artery intima-media thickness (CIMT) measurements were also collected. We examined a total of 16 CpG loci located within NOS1, NOS2A, NOS3, ARG1, and ARG2 genes responsible for NO production. CIMT was measured using high-resolution B-mode carotid ultrasound. The association between percentage DNA methylation in ARG and NOS genes with CIMT was evaluated using linear regression adjusted for sex, ethnicity, body mass index, age at CIMT, town of residence, and experimental plate for pyrosequencing reactions. Differences in the association by ethnicity and ancestral group were also evaluated. For a 1% increase in average DNA methylation of NOS1, CIMT increased by 1.2 μm (P=0.02). This association was greater in Hispanic children of Native American descent (β=2.3; P=0.004) than in non-Hispanic whites (β=0.3; P=0.71) or Hispanic whites (β=1.0; P=0.35). CONCLUSIONS DNA methylation of NOS1 has a plausible role in atherogenesis through regulation of NO production, although ancestry may alter the magnitude of this association.
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Affiliation(s)
- Carrie V Breton
- Department of Preventive Medicine and Atherosclerosis Research Unit, University of Southern California, Los Angeles, CA
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Voituron N, Jeton F, Cholley Y, Hasnaoui-Saadani RE, Marchant D, Quidu P, Favret F, Richalet JP, Pichon A. Catalyzing role of erythropoietin on the nitric oxide central pathway during the ventilatory responses to hypoxia. Physiol Rep 2014; 2:e00223. [PMID: 24744892 PMCID: PMC3966246 DOI: 10.1002/phy2.223] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/09/2014] [Accepted: 01/11/2014] [Indexed: 02/03/2023] Open
Abstract
The N‐Methyl‐d‐Aspartate (NMDA) receptors – neuronal nitric oxide synthase (nNOS) pathway is involved in the ventilatory response to hypoxia. The objective was to assess the possible effect of erythropoietin deficiency and chronic exposure to hypoxia on this pathway during ventilatory response to acute hypoxia. Wild‐type (WT) and erythropoietin‐deficient (Epo‐TAgh) male mice were exposed (14 days) either to hypobaric hypoxia (Pb = 435 mmHg) or to normoxia. The ventilation was measured at 21% or 8% O2 after injection of vehicle (NaCl), nNOS inhibitor (SMTC) or NMDA receptor antagonist (MK‐801). Nitric oxide production and the expression of NMDA receptor and nNOS were assessed by real‐time RT‐PCR and Western blot analyses in the medulla. At rest, Epo‐TAgh mice displayed normal ventilatory parameters at 21% O2 but did not respond to acute hypoxia despite a larger expression of NMDA receptors and nNOS in the medulla. Ventilatory acclimatization to hypoxia was observed in WT but was absent in Epo‐TAgh mice. nNOS inhibition blunted the hypoxic ventilatory acclimatization of WT mice without any effect in Epo‐TAgh mice. Acute hypoxic ventilatory response (HVR) was increased after chronic hypoxia in WT but remained unchanged in Epo‐TAgh mice. Ventilatory response to acute hypoxia was modified by MK‐801 injection in WT and Epo‐TAgh mice. The results confirm that adequate erythropoietin level is necessary to obtain an appropriate HVR and a significant ventilatory acclimatization to hypoxia. Furthermore, erythropoietin plays a potential catalyzing role in the NMDA‐NO central pathway during the ventilatory response and acclimatization to hypoxia. e00223 Adequate erythropoietin level is necessary to obtain an appropriate hypoxic ventilatory response and a significant ventilatory acclimatization to hypoxia. Erythropoietin plays a potential catalyzing role on the N‐Methyl‐d‐Aspartate (NMDA)‐nNOS central pathway during the ventilatory response and acclimatization to hypoxia.
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Affiliation(s)
- Nicolas Voituron
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France ; Laboratory of Excellence (Labex) GR-Ex, PRES Sorbonne Paris Cité
| | - Florine Jeton
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France ; Laboratory of Excellence (Labex) GR-Ex, PRES Sorbonne Paris Cité
| | - Yannick Cholley
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France
| | - Raja El Hasnaoui-Saadani
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France
| | - Dominique Marchant
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France
| | - Patricia Quidu
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France
| | - Fabrice Favret
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France
| | - Jean-Paul Richalet
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France ; Laboratory of Excellence (Labex) GR-Ex, PRES Sorbonne Paris Cité
| | - Aurélien Pichon
- Laboratoire "Réponses cellulaires et fonctionnelles à l'hypoxie", Université Paris 13, Sorbonne Paris Cité, UFR SMBH, EA 2363, Bobigny, 93017, France ; Laboratory of Excellence (Labex) GR-Ex, PRES Sorbonne Paris Cité
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Yu L, Vásquez-Vivar J, Jiang R, Luo K, Derrick M, Tan S. Developmental susceptibility of neurons to transient tetrahydrobiopterin insufficiency and antenatal hypoxia-ischemia in fetal rabbits. Free Radic Biol Med 2014; 67:426-36. [PMID: 24316196 PMCID: PMC3945116 DOI: 10.1016/j.freeradbiomed.2013.11.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 11/22/2013] [Accepted: 11/25/2013] [Indexed: 01/13/2023]
Abstract
Tetrahydrobiopterin (BH4) is important for normal brain development as congenital BH4 deficiencies manifest movement disorders at various childhood ages. BH4 transitions from very low levels in fetal brains to higher "adult" levels postnatally, with the highest levels in the thalamus. Maternal supplementation with the BH4 precursor sepiapterin reduces postnatal motor deficits and perinatal deaths after 40-min fetal hypoxia-ischemia (HI) at 70% gestation, suggesting that brain BH4 is important in improving function after HI. We tested the hypothesis that the intrinsically low concentrations of BH4 made fetal neurons vulnerable to added insults. Brains were obtained from naïve fetal rabbits or after 40-min HI, at 70% (E22) and 92% gestation (E29). Neuronal cultures were prepared from basal ganglia, cortex, and thalamus, regions with different intrinsic levels of BH4. Cultures were grown with or without added BH4 for 48h. Cell survival and mitochondrial function were determined by flow cytometry. At E22, thalamic cells had the lowest survival rate in a BH4-free milieu, in both control and HI groups, whereas BH4 supplementation ex vivo increased neuronal survival only in HI cells. Neuronal survival was similar in all regions without BH4 at E29. BH4 supplementation increased cell survival and cells with intact mitochondrial membrane potential, from basal ganglia and cortex, but not thalamus. After E29 HI, however, the benefit of BH4 was limited to cortical neurons. We conclude that BH4 is important for fetal neuronal survival after HI especially in the premature thalamus. Supplementation of BH4 has a greater benefit at an earlier gestational age.
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Affiliation(s)
- Lei Yu
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Jeannette Vásquez-Vivar
- Department of Biophysics and Free Radical Research Center & Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee WI 53226
| | - Rugang Jiang
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Kehuan Luo
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Matthew Derrick
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
| | - Sidhartha Tan
- Department of Pediatrics, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, IL 60201
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Vaideeswaran S, Ramaiah S. Investigations on the role of π-π interactions and π-π networks in eNOS and nNOS proteins. Bioorg Chem 2013; 49:16-23. [PMID: 23845761 DOI: 10.1016/j.bioorg.2013.06.005] [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: 10/01/2012] [Revised: 04/16/2013] [Accepted: 06/03/2013] [Indexed: 10/26/2022]
Abstract
π-π Interactions play an important role in the stability of protein structures. In the present study, we have analyzed the influence of π-π interactions in eNOS and nNOS proteins. The contribution of these π-π interacting residues in sequential separation, secondary structure involvement, solvent accessibility and stabilization centers has been evaluated. π-π interactions stabilize the core regions within eNOS and nNOS proteins. π-π interacting residues are evolutionary conserved. There is a significant number of π-π interactions in spite of the lesser natural occurrences of π-residues in eNOS and nNOS proteins. In addition to π-π interactions, π residues also form π-π networks in both eNOS and nNOS proteins which might play an important role in the structural stability of these protein structures.
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Affiliation(s)
- Sivasakthi Vaideeswaran
- Bioinformatics Division, School of Biosciences and Technology, VIT University, Vellore 632 014, Tamil Nadu, India
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Hu T, Beattie WS, Mazer CD, Leong-Poi H, Fujii H, Wilson DF, Tsui AKY, Liu E, Muhammad M, Baker AJ, Hare GMT. Treatment with a highly selective β₁ antagonist causes dose-dependent impairment of cerebral perfusion after hemodilution in rats. Anesth Analg 2013; 116:649-62. [PMID: 23400988 DOI: 10.1213/ane.0b013e318280e26d] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Acute β-blockade has been associated with a dose-dependent increase in adverse outcomes, including stroke and mortality. Acute blood loss contributes to the incidence of these adverse events. In an attempt to link the risks of acute blood loss and β-blockade, animal studies have demonstrated that acute β-blockade impairs cerebral perfusion after hemodilution. We expanded on these findings by testing the hypothesis that acute β-blockade with a highly β(1)-specific antagonist (nebivolol) causes dose-dependent cerebral hypoxia during hemodilution. METHODS Anesthetized rats and mice were randomized to receive vehicle or nebivolol (1.25 or 2.5 mg/kg) IV before hemodilution to a hemoglobin concentration near 60 g/L. Drug levels, heart rate (HR), cardiac output (CO), regional cerebral blood flow (rCBF, laser Doppler), and microvascular brain Po(2) (P(Br)O(2), G2 Oxyphor) were measured before and after hemodilution. Endothelial nitric oxide synthase (NOS), neuronal NOS (nNOS), inducible NOS, and hypoxia inducible factor (HIF)-1α were assessed by Western blot. HIF-α expression was also assessed using an HIF-(ODD)-luciferase mouse model. Data were analyzed using analysis of variance with significance assigned at P < 0.05, and corrected P values are reported for all post hoc analyses. RESULTS Nebivolol treatment resulted in dose-specific plasma drug levels. In vehicle-treated rats, hemodilution increased CO and rCBF (P < 0.010) whereas P(Br)O(2) decreased to 45.8 ± 18.7 mm Hg (corrected P < 0.001; 95% CI 29.4-69.7). Both nebivolol doses comparably reduced HR and attenuated the CO response to hemodilution (P < 0.012). Low-dose nebivolol did not impair rCBF or further reduce P(Br)O(2) after hemodilution. High-dose nebivolol attenuated the rCBF response to hemodilution and caused a further reduction in P(Br)O(2) to 28.4 ± 9.6 mm Hg (corrected P = 0.019; 95% CI 17.4-42.7). Both nebivolol doses increased brain endothelial NOS protein levels. Brain HIF-1α, inducible NOS, and nNOS protein levels and brain HIF-luciferase activity were increased in the high-dose nebivolol group after hemodilution (P < 0.032). CONCLUSIONS Our data demonstrate that nebivolol resulted in a dose-dependent decrease in cerebral oxygen delivery after hemodilution as reflected by a decrease in brain tissue Po(2) and an increase in hypoxic protein responses (HIF-1α and nNOS). Low-dose nebivolol treatment did not result in worsened tissue hypoxia after hemodilution, despite comparable effects on HR and CO. These data support the hypothesis that acute β-blockade with a highly β(1)-specific antagonist causes a dose-dependent impairment in cerebral perfusion during hemodilution.
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Affiliation(s)
- Tina Hu
- Department of Anesthesia, Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, University of Toronto, 30 Bond St., Toronto, ON M5B 1W8, Canada
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Giaroni C, Marchet S, Carpanese E, Prandoni V, Oldrini R, Bartolini B, Moro E, Vigetti D, Crema F, Lecchini S, Frigo G. Role of neuronal and inducible nitric oxide synthases in the guinea pig ileum myenteric plexus during in vitro ischemia and reperfusion. Neurogastroenterol Motil 2013; 25:e114-26. [PMID: 23279126 DOI: 10.1111/nmo.12061] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Intestinal ischemia and reperfusion (I/R) injury leads to abnormalities in motility, namely delay of transit, caused by damage to myenteric neurons. Alterations of the nitrergic transmission may occur in these conditions. This study investigated whether an in vitro I/R injury may affect nitric oxide (NO) production from the myenteric plexus of the guinea pig ileum and which NO synthase (NOS) isoform is involved. METHODS The distribution of the neuronal (n) and inducible (i) NOS was determined by immunohistochemistry during 60 min of glucose/oxygen deprivation (in vitro ischemia) followed by 60 min of reperfusion. The protein and mRNA levels of nNOS and iNOS were investigated by Western-immunoblotting and real time RT-PCR, respectively. NO levels were quantified as nitrite/nitrate. KEY RESULTS After in vitro I/R the proportion of nNOS-expressing neurons and protein levels remained unchanged. nNOS mRNA levels increased 60 min after inducing ischemia and in the following 5 min of reperfusion. iNOS-immunoreactive neurons, protein and mRNA levels were up-regulated during the whole I/R period. A significant increase of nitrite/nitrate levels was observed in the first 5 min after inducing I/R and was significantly reduced by N(ω) -propyl-l-arginine and 1400 W, selective inhibitors of nNOS and iNOS, respectively. CONCLUSIONS & INFERENCES Our data demonstrate that both iNOS and nNOS represent sources for NO overproduction in ileal myenteric plexus during I/R, although iNOS undergoes more consistent changes suggesting a more relevant role for this isoform in the alterations occurring in myenteric neurons following I/R.
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Affiliation(s)
- C Giaroni
- Department of Clinical and Experimental Medicine, University of Insubria, Varese, Italy.
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Virarkar M, Alappat L, Bradford PG, Awad AB. L-Arginine and Nitric Oxide in CNS Function and Neurodegenerative Diseases. Crit Rev Food Sci Nutr 2013; 53:1157-67. [DOI: 10.1080/10408398.2011.573885] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Prabhakar NR, Semenza GL. Adaptive and maladaptive cardiorespiratory responses to continuous and intermittent hypoxia mediated by hypoxia-inducible factors 1 and 2. Physiol Rev 2012; 92:967-1003. [PMID: 22811423 DOI: 10.1152/physrev.00030.2011] [Citation(s) in RCA: 429] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Hypoxia is a fundamental stimulus that impacts cells, tissues, organs, and physiological systems. The discovery of hypoxia-inducible factor-1 (HIF-1) and subsequent identification of other members of the HIF family of transcriptional activators has provided insight into the molecular underpinnings of oxygen homeostasis. This review focuses on the mechanisms of HIF activation and their roles in physiological and pathophysiological responses to hypoxia, with an emphasis on the cardiorespiratory systems. HIFs are heterodimers comprised of an O(2)-regulated HIF-1α or HIF-2α subunit and a constitutively expressed HIF-1β subunit. Induction of HIF activity under conditions of reduced O(2) availability requires stabilization of HIF-1α and HIF-2α due to reduced prolyl hydroxylation, dimerization with HIF-1β, and interaction with coactivators due to decreased asparaginyl hydroxylation. Stimuli other than hypoxia, such as nitric oxide and reactive oxygen species, can also activate HIFs. HIF-1 and HIF-2 are essential for acute O(2) sensing by the carotid body, and their coordinated transcriptional activation is critical for physiological adaptations to chronic hypoxia including erythropoiesis, vascularization, metabolic reprogramming, and ventilatory acclimatization. In contrast, intermittent hypoxia, which occurs in association with sleep-disordered breathing, results in an imbalance between HIF-1α and HIF-2α that causes oxidative stress, leading to cardiorespiratory pathology.
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Affiliation(s)
- Nanduri R Prabhakar
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, Biological Sciences Division, University of Chicago, Chicago, Illinois, USA.
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Saxena S, Shukla D, Bansal A. Augmentation of aerobic respiration and mitochondrial biogenesis in skeletal muscle by hypoxia preconditioning with cobalt chloride. Toxicol Appl Pharmacol 2012; 264:324-34. [PMID: 22982409 DOI: 10.1016/j.taap.2012.08.033] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 08/08/2012] [Accepted: 08/30/2012] [Indexed: 11/19/2022]
Abstract
High altitude/hypoxia training is known to improve physical performance in athletes. Hypoxia induces hypoxia inducible factor-1 (HIF-1) and its downstream genes that facilitate hypoxia adaptation in muscle to increase physical performance. Cobalt chloride (CoCl₂), a hypoxia mimetic, stabilizes HIF-1, which otherwise is degraded in normoxic conditions. We studied the effects of hypoxia preconditioning by CoCl₂ supplementation on physical performance, glucose metabolism, and mitochondrial biogenesis using rodent model. The results showed significant increase in physical performance in cobalt supplemented rats without (two times) or with training (3.3 times) as compared to control animals. CoCl₂ supplementation in rats augmented the biological activities of enzymes of TCA cycle, glycolysis and cytochrome c oxidase (COX); and increased the expression of glucose transporter-1 (Glut-1) in muscle showing increased glucose metabolism by aerobic respiration. There was also an increase in mitochondrial biogenesis in skeletal muscle observed by increased mRNA expressions of mitochondrial biogenesis markers which was further confirmed by electron microscopy. Moreover, nitric oxide production increased in skeletal muscle in cobalt supplemented rats, which seems to be the major reason for peroxisome proliferator activated receptor-gamma coactivator-1α (PGC-1α) induction and mitochondrial biogenesis. Thus, in conclusion, we state that hypoxia preconditioning by CoCl₂ supplementation in rats increases mitochondrial biogenesis, glucose uptake and metabolism by aerobic respiration in skeletal muscle, which leads to increased physical performance. The significance of this study lies in understanding the molecular mechanism of hypoxia adaptation and improvement of work performance in normal as well as extreme conditions like hypoxia via hypoxia preconditioning.
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Affiliation(s)
- Saurabh Saxena
- Experimental Biology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India
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Ho JJD, Metcalf JL, Yan MS, Turgeon PJ, Wang JJ, Chalsev M, Petruzziello-Pellegrini TN, Tsui AKY, He JZ, Dhamko H, Man HSJ, Robb GB, Teh BT, Ohh M, Marsden PA. Functional importance of Dicer protein in the adaptive cellular response to hypoxia. J Biol Chem 2012; 287:29003-20. [PMID: 22745131 PMCID: PMC3436557 DOI: 10.1074/jbc.m112.373365] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 06/19/2012] [Indexed: 01/06/2023] Open
Abstract
The processes by which cells sense and respond to ambient oxygen concentration are fundamental to cell survival and function, and they commonly target gene regulatory events. To date, however, little is known about the link between the microRNA pathway and hypoxia signaling. Here, we show in vitro and in vivo that chronic hypoxia impairs Dicer (DICER1) expression and activity, resulting in global consequences on microRNA biogenesis. We show that von Hippel-Lindau-dependent down-regulation of Dicer is key to the expression and function of hypoxia-inducible factor α (HIF-α) subunits. Specifically, we show that EPAS1/HIF-2α is regulated by the Dicer-dependent microRNA miR-185, which is down-regulated by hypoxia. Full expression of hypoxia-responsive/HIF target genes in chronic hypoxia (e.g. VEGFA, FLT1/VEGFR1, KDR/VEGFR2, BNIP3L, and SLC2A1/GLUT1), the function of which is to regulate various adaptive responses to compromised oxygen availability, is also dependent on hypoxia-mediated down-regulation of Dicer function and changes in post-transcriptional gene regulation. Therefore, functional deficiency of Dicer in chronic hypoxia is relevant to both HIF-α isoforms and hypoxia-responsive/HIF target genes, especially in the vascular endothelium. These findings have relevance to emerging therapies given that we show that the efficacy of RNA interference under chronic hypoxia, but not normal oxygen availability, is Dicer-dependent. Collectively, these findings show that the down-regulation of Dicer under chronic hypoxia is an adaptive mechanism that serves to maintain the cellular hypoxic response through HIF-α- and microRNA-dependent mechanisms, thereby providing an essential mechanistic insight into the oxygen-dependent microRNA regulatory pathway.
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Affiliation(s)
- J. J. David Ho
- From the Departments of Medical Biophysics and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | | | - Matthew S. Yan
- From the Departments of Medical Biophysics and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Paul J. Turgeon
- Laboratory Medicine and Pathobiology and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Jenny Jing Wang
- Laboratory Medicine and Pathobiology and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Maria Chalsev
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Tania N. Petruzziello-Pellegrini
- Laboratory Medicine and Pathobiology and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Albert K. Y. Tsui
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - Jeff Z. He
- Laboratory Medicine and Pathobiology and
| | - Helena Dhamko
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - H. S. Jeffrey Man
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
| | - G. Brett Robb
- Division of RNA Biology, New England Biolabs, Ipswich, Massachusetts 01938-2723, and
| | - Bin T. Teh
- Van Andel Research Institute, Grand Rapids, Michigan 49503
| | | | - Philip A. Marsden
- From the Departments of Medical Biophysics and
- Laboratory Medicine and Pathobiology and
- Keenan Research Centre in the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada
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Locally different endothelial nitric oxide synthase protein levels in ascending aortic aneurysms of bicuspid and tricuspid aortic valve. Cardiol Res Pract 2012; 2012:165957. [PMID: 22745920 PMCID: PMC3382953 DOI: 10.1155/2012/165957] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 03/26/2012] [Accepted: 03/28/2012] [Indexed: 11/17/2022] Open
Abstract
Aims. Dysregulated expression of the endothelial nitric oxide synthase (eNOS) is observed in aortic aneurysms associated with bicuspid aortic valve (BAV). We determined eNOS protein levels in various areas in ascending aortic aneurysms.
Methods and Results. Aneurysmal specimens were collected from 19 patients, 14 with BAV and 5 with tricuspid aortic valve (TAV). ENOS protein levels were measured in the outer curve (convexity), the opposite side (concavity), the distal and above the sinotubular junction (proximal) aneurysm. Cultured aortic cells were treated with NO synthesis inhibitor L-NAME and the amounts of 35 apoptosis-related proteins were determined. In patients with BAV, eNOS levels were significantly lower in the proximal aorta than in the concavity and distal aorta. ENOS protein levels were also lower in the convexity than in the concavity. While the convexity and distal aorta showed similar eNOS protein levels in BAV and TAV patients, levels were higher in TAV proximal aorta. Inhibition of NO synthesis in aneurysmal aortic cells by L-NAME led to a cytosolic increase in the levels of mitochondrial serine protease HTRA2/Omi. Conclusion. ENOS protein levels were varied at different areas of the aneurysmal aorta. The dysregulation of nitric oxide can lead to an increase in proapoptotic HTRA2/Omi.
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Ho JJD, Man HSJ, Marsden PA. Nitric oxide signaling in hypoxia. J Mol Med (Berl) 2012; 90:217-31. [DOI: 10.1007/s00109-012-0880-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 02/03/2012] [Accepted: 02/06/2012] [Indexed: 01/06/2023]
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Hare GMT, Mu A, Romaschin A, Tsui AKY, Shehata N, Beattie WS, Mazer CD. Plasma methemoglobin as a potential biomarker of anemic stress in humans. Can J Anaesth 2012; 59:348-56. [DOI: 10.1007/s12630-011-9663-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Accepted: 12/21/2011] [Indexed: 11/30/2022] Open
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Abstract
It has been known for more than 60 years, and suspected for over 100, that alveolar hypoxia causes pulmonary vasoconstriction by means of mechanisms local to the lung. For the last 20 years, it has been clear that the essential sensor, transduction, and effector mechanisms responsible for hypoxic pulmonary vasoconstriction (HPV) reside in the pulmonary arterial smooth muscle cell. The main focus of this review is the cellular and molecular work performed to clarify these intrinsic mechanisms and to determine how they are facilitated and inhibited by the extrinsic influences of other cells. Because the interaction of intrinsic and extrinsic mechanisms is likely to shape expression of HPV in vivo, we relate results obtained in cells to HPV in more intact preparations, such as intact and isolated lungs and isolated pulmonary vessels. Finally, we evaluate evidence regarding the contribution of HPV to the physiological and pathophysiological processes involved in the transition from fetal to neonatal life, pulmonary gas exchange, high-altitude pulmonary edema, and pulmonary hypertension. Although understanding of HPV has advanced significantly, major areas of ignorance and uncertainty await resolution.
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Affiliation(s)
- J. T. Sylvester
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and Division of Asthma, Allergy and Lung Biology, School of Medicine, King's College, London, United Kingdom
| | - Larissa A. Shimoda
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and Division of Asthma, Allergy and Lung Biology, School of Medicine, King's College, London, United Kingdom
| | - Philip I. Aaronson
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and Division of Asthma, Allergy and Lung Biology, School of Medicine, King's College, London, United Kingdom
| | - Jeremy P. T. Ward
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and Division of Asthma, Allergy and Lung Biology, School of Medicine, King's College, London, United Kingdom
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Everett MV, Antal CE, Crawford DL. The effect of short-term hypoxic exposure on metabolic gene expression. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL GENETICS AND PHYSIOLOGY 2012; 317:9-23. [PMID: 22021243 PMCID: PMC3237964 DOI: 10.1002/jez.717] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 08/04/2011] [Accepted: 08/24/2011] [Indexed: 11/09/2022]
Abstract
The long-term effect of hypoxia is to decrease both the production and use of ATP and thus decrease the reliance on mitochondrial oxidative energy production. Yet, recent studies include more immediate affects of hypoxia on gene expression and these data suggest the maintenance of mitochondrial function. To better understand the short-term physiological response to hypoxia, we quantified metabolic mRNA expression in the heart ventricles and livers of the teleost fish Fundulus grandis exposed to partial oxygen pressure of 2.8 kPa (-13.5% air saturation).Twenty-eight individuals from a single population were exposed to hypoxia for 0, 4, 8, 12, 24, 48, and 96 hr. Liver and cardiac tissues were sampled from the same individuals at 0-48 hr. At 96 hr, only cardiac tissue was assayed. Gene expression was significantly different (ANOVA, P < 0.05) for 17 of 226 metabolic genes (7.5%) in cardiac tissue and for 20 of 256 (7.8%) metabolic genes in hepatic tissue. For the two tissues examined in this study, the maximum response occurred at different times. For cardiac tissue, using Dunnett's post hoc test, most of these significant differences occurred at 96 hr of exposure. For liver, all but one significant difference occurred at 4 hr. Surprisingly, too many (relative to random expectations) of the genes with significant increase in mRNA are involved in the oxidative phosphorylation pathway: 44% of the significant genes at 96 hr in the heart and 33% of the significant genes at 4 hr in the liver are involved in the oxidative phosphorylation pathway. These data indicate that there are tissue-specific differences in the timing of the response to hypoxia, yet both cardiac and hepatic tissues have increases in mRNA that code for enzyme in the oxidative phosphorylation pathway. If these changes in mRNA produce a similar change in protein, then these data suggest that the initial response to hypoxia involves an increase in the oxidative pathway potentially as a mechanism to maintain ATP production.
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Affiliation(s)
- Meredith V. Everett
- Marine Biology and Fisheries□Rosenstiel School of Marine and Atmospheric Science University of Miami 4600 Rickenbacker Causeway Miami, FL 33149-1098 USA
| | - Corina E. Antal
- Marine Biology and Fisheries□Rosenstiel School of Marine and Atmospheric Science University of Miami 4600 Rickenbacker Causeway Miami, FL 33149-1098 USA
| | - Douglas L. Crawford
- Marine Biology and Fisheries□Rosenstiel School of Marine and Atmospheric Science University of Miami 4600 Rickenbacker Causeway Miami, FL 33149-1098 USA
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45
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Priming of hypoxia-inducible factor by neuronal nitric oxide synthase is essential for adaptive responses to severe anemia. Proc Natl Acad Sci U S A 2011; 108:17544-9. [PMID: 21976486 DOI: 10.1073/pnas.1114026108] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cells sense and respond to changes in oxygen concentration through gene regulatory processes that are fundamental to survival. Surprisingly, little is known about how anemia affects hypoxia signaling. Because nitric oxide synthases (NOSs) figure prominently in the cellular responses to acute hypoxia, we defined the effects of NOS deficiency in acute anemia. In contrast to endothelial NOS or inducible NOS deficiency, neuronal NOS (nNOS)(-/-) mice demonstrated increased mortality during anemia. Unlike wild-type (WT) animals, anemia did not increase cardiac output (CO) or reduce systemic vascular resistance (SVR) in nNOS(-/-) mice. At the cellular level, anemia increased expression of HIF-1α protein and HIF-responsive mRNA levels (EPO, VEGF, GLUT1, PDK1) in the brain of WT, but not nNOS(-/-) mice, despite comparable reductions in tissue PO(2). Paradoxically, nNOS(-/-) mice survived longer during hypoxia, retained the ability to regulate CO and SVR, and increased brain HIF-α protein levels and HIF-responsive mRNA transcripts. Real-time imaging of transgenic animals expressing a reporter HIF-α(ODD)-luciferase chimeric protein confirmed that nNOS was essential for anemia-mediated increases in HIF-α protein stability in vivo. S-nitrosylation effects the functional interaction between HIF and pVHL. We found that anemia led to nNOS-dependent S-nitrosylation of pVHL in vivo and, of interest, led to decreased expression of GSNO reductase. These findings identify nNOS effects on the HIF/pVHL signaling pathway as critically important in the physiological responses to anemia in vivo and provide essential mechanistic insight into the differences between anemia and hypoxia.
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46
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Zhang YH, Casadei B. Sub-cellular targeting of constitutive NOS in health and disease. J Mol Cell Cardiol 2011; 52:341-50. [PMID: 21945464 DOI: 10.1016/j.yjmcc.2011.09.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 09/07/2011] [Accepted: 09/08/2011] [Indexed: 02/04/2023]
Abstract
Constitutive nitric oxide synthases (NOSs) are ubiquitous enzymes that play a pivotal role in the regulation of myocardial function in health and disease. The discovery of both a neuronal NOS (nNOS) and an endothelial NOS (eNOS) isoform in the myocardium and the availability of genetically modified mice with selective eNOS or nNOS gene deletion have been of crucial importance for understanding the role of constitutive nitric oxide (NO) production in the myocardium. eNOS and nNOS are homologous in structure and utilize the same co-factors and substrates; however, they differ in their subcellular localization, regulation, and downstream signaling, all of which may account for their distinct effects on excitation-contraction coupling. In particular, eNOS-derived NO has been reported to increase left ventricular (LV) compliance, attenuate beta-adrenergic inotropy and enhance parasympathetic/muscarinic responses, and mediate the negative inotropic response to β3 adrenoreceptor stimulation via cGMP-dependent signaling. Conversely, nNOS-derived NO regulates basal myocardial inotropy and relaxation by inhibiting the sarcolemmal Ca(2+) current (I(Ca)) and promoting protein kinase A-dependent phospholamban (PLN) phosphorylation, independent of cGMP. By inhibiting the activity of myocardial oxidase systems, nNOS regulates the redox state of the myocardium and contributes to maintain eNOS "coupled" activity. After myocardial infarction, up-regulation of myocardial nNOS attenuates adverse remodeling and prevents arrhythmias whereas uncoupled eNOS activity in murine models of left ventricular pressure overload accelerates the progress towards heart failure. Here we review the evidence in support of the idea that NOS subcellular localization, mode of activation, and downstream signaling account for the diverse and highly specialized actions of NO in the heart. This article is part of a Special Issue entitled "Local Signaling in Myocytes".
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Affiliation(s)
- Yin Hua Zhang
- Department of Physiology, Seoul National University, College of Medicine, Seoul, Republic of Korea
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47
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Soskić SS, Dobutović BD, Sudar EM, Obradović MM, Nikolić DM, Djordjevic JD, Radak DJ, Mikhailidis DP, Isenović ER. Regulation of Inducible Nitric Oxide Synthase (iNOS) and its Potential Role in Insulin Resistance, Diabetes and Heart Failure. Open Cardiovasc Med J 2011; 5:153-63. [PMID: 21792376 PMCID: PMC3141344 DOI: 10.2174/1874192401105010153] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 02/08/2023] Open
Abstract
Nitric oxide synthases (NOS) are the enzymes responsible for nitric oxide (NO) generation. NO is a reactive oxygen species as well as a reactive nitrogen species. It is a free radical which mediates several biological effects. It is clear that the generation and actions of NO under physiological and pathophysiological conditions are regulated and extend to almost every cell type and function within the circulation. In mammals 3 distinct isoforms of NOS have been identified: neuronal NOS (nNOS), inducible NOS (iNOS) and endothelial NOS (eNOS). The important isoform in the regulation of insulin resistance (IR) is iNOS. Understanding the molecular mechanisms regulating the iNOS pathway in normal and hyperglycemic conditions would help to explain some of vascular abnormalities observed in type 2 diabetes mellitus (T2DM). Previous studies have reported increased myocardial iNOS activity and expression in heart failure (HF). This review considers the recent animal studies which focus on the understanding of regulation of iNOS activity/expression and the role of iNOS agonists as potential therapeutic agents in treatment of IR, T2DM and HF.
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Affiliation(s)
- Sanja S Soskić
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Branislava D Dobutović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Emina M Sudar
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Milan M Obradović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Dragana M Nikolić
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
| | - Jelena D Djordjevic
- Institute of Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Studentski trg 16, 11000 Belgrade, P.O.Box S2 Republic of Serbia
| | - Djordje J Radak
- Department of Vascular Surgery, Dedinje Cardiovascular Institute, Belgrade University School of Medicine, Belgrade, Serbia
| | - Dimitri P Mikhailidis
- Department of Clinical Biochemistry (Vascular Disease Prevention Clinics), Royal Free campus, University College London Medical School, University College London (UCL), Pond Street, London NW3 2QG, UK
| | - Esma R Isenović
- Laboratory for Radiobiology and Molecular Genetics, Institute "Vinča", University of Belgrade, Serbia
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Weigand L, Shimoda LA, Sylvester JT. Enhancement of myofilament calcium sensitivity by acute hypoxia in rat distal pulmonary arteries. Am J Physiol Lung Cell Mol Physiol 2011; 301:L380-7. [PMID: 21665962 DOI: 10.1152/ajplung.00068.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hypoxic contraction of pulmonary arterial smooth muscle is thought to require increases in both intracellular Ca(2+) concentration ([Ca(2+)](i)) and myofilament Ca(2+) sensitivity, which may or may not be endothelium-dependent. To examine the effects of hypoxia and endothelium on Ca(2+) sensitivity in pulmonary arterial smooth muscle, we measured the relation between [Ca(2+)](i) and isometric force at 37°C during normoxia (21% O(2)-5% CO(2)) and after 30 min of hypoxia (1% O(2)-5% CO(2)) in endothelium-intact (E+) and -denuded (E-) rat distal intrapulmonary arteries (IPA) permeabilized with staphylococcal α-toxin. Endothelial denudation enhanced Ca(2+) sensitivity during normoxia but did not alter the effects of hypoxia, which shifted the [Ca(2+)](i)-force relation to higher force in E+ and E- IPA. Neither hypoxia nor endothelial denudation altered Ca(2+) sensitivity in mesenteric arteries. In E+ and E- IPA, hypoxic enhancement of Ca(2+) sensitivity was abolished by the nitric oxide synthase inhibitor N(ω)-nitro-l-arginine methyl ester (30 μM), which shifted normoxic [Ca(2+)](i)-force relations to higher force. In E- IPA, the Rho kinase antagonist Y-27632 (10 μM) shifted the normoxic [Ca(2+)](i)-force relation to lower force but did not alter the effects of hypoxia. These results suggest that acute hypoxia enhanced myofilament Ca(2+) sensitivity in rat IPA by decreasing nitric oxide production and/or activity in smooth muscle, thereby revealing a high basal level of Ca(2+) sensitivity, due in part to Rho kinase, which otherwise did not contribute to Ca(2+) sensitization by hypoxia.
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Affiliation(s)
- Letitia Weigand
- Div. of Pulmonary and Critical Care Medicine, The Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Cir., Baltimore, MD 21224, USA
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Hypoxia-mediated control of HIF/ARNT machinery in epidermal keratinocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1813:60-72. [DOI: 10.1016/j.bbamcr.2010.11.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 11/19/2010] [Accepted: 11/22/2010] [Indexed: 11/22/2022]
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50
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Percival JM, Adamo CM, Beavo JA, Froehner SC. Evaluation of the therapeutic utility of phosphodiesterase 5A inhibition in the mdx mouse model of duchenne muscular dystrophy. Handb Exp Pharmacol 2011:323-44. [PMID: 21695647 DOI: 10.1007/978-3-642-17969-3_14] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Duchenne muscular dystrophy (DMD) is a devastating and ultimately fatal disease characterized by progressive muscle wasting and weakness. DMD is caused by the absence of a functional dystrophin protein, which in turn leads to reduced expression and mislocalization of dystrophin-associated proteins including neuronal nitric oxide (NO) synthase mu (nNOSμ). Disruption of nNOSμ signaling results in muscle fatigue and unopposed sympathetic vasoconstriction during exercise, thereby increasing contraction-induced damage in dystrophin-deficient muscles. The loss of normal nNOSμ signaling during exercise is central to the vascular dysfunction proposed over 40 years ago to be an important pathogenic mechanism in DMD. Recent preclinical studies focused on circumventing defective nNOSμ signaling in dystrophic skeletal and cardiac muscle by inhibiting phosphodiesterase 5A (PDE5A) have shown promising results. This review addresses nNOS signaling in normal and dystrophin-deficient muscles and the potential of PDE5A inhibition as a therapeutic approach for the treatment of cardiovascular deficits in DMD.
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Affiliation(s)
- Justin M Percival
- Department of Physiology and Biophysics, University of Washington, 357290, 98195-7290, Seattle, WA, USA.
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