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Mohit, Tomar MS, Sharma D, Nandan S, Pateriya A, Shrivastava A, Chand P. Emerging role of metabolomics for biomarker discovery in obstructive sleep apnea. Sleep Breath 2023; 27:1247-1254. [PMID: 36322226 DOI: 10.1007/s11325-022-02730-y] [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: 03/24/2022] [Revised: 09/29/2022] [Accepted: 10/13/2022] [Indexed: 03/12/2023]
Abstract
Obstructive sleep apnea (OSA) is characterized by the complete or partial blockage of the upper airway passage during sleep which causes repetitive breaks in sleep and may result in excessive daytime sleepiness. OSA has been linked to various metabolic disorders and chronic health conditions, such as obesity, diabetes, hypertension, and depression. Profiling of alterations in metabolites and their regulation in OSA has been hypothesized to be an effective approach for early diagnosis and prognosis of OSA. Several studies have characterized metabolic fingerprints associated with sleep disorders. There is a lack of understanding of metabolite contents and their alterations in OSA that may help to identify specific biomarkers. The information provided in this review will help update new methodologies and interventions of high throughput advanced molecular/metabolomics tools which may clarify the metabolic aspects and mechanisms for improved management and treatment of OSA.
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Affiliation(s)
- Mohit
- Department of Prosthodontics, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India
- Center for Advance Research, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India
| | - Manendra Singh Tomar
- Center for Advance Research, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India
| | - Deepak Sharma
- Council of Scientific & Industrial Research, Phytochemistry Division, National Botanical Research Institute, Uttar Pradesh, Lucknow, 226001, India
| | - Shiv Nandan
- Department of Biotechnology, Era's Lucknow Medical College & Hospital, Uttar Pradesh, Lucknow, 226003, India
| | - Ankit Pateriya
- Center for Advance Research, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India
| | - Ashutosh Shrivastava
- Center for Advance Research, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India.
| | - Pooran Chand
- Department of Prosthodontics, King George's Medical University Lucknow, Uttar Pradesh, Lucknow, 226003, India.
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Carey ME, Rando J, Melnyk S, James SJ, Snyder N, Salafia C, Croen LA, Fallin MD, Hertz-Picciotto I, Volk H, Newschaffer C, Lyall K. Examining associations between prenatal biomarkers of oxidative stress and ASD-related outcomes using quantile regression. J Autism Dev Disord 2023; 53:2975-2985. [PMID: 35678944 PMCID: PMC9732143 DOI: 10.1007/s10803-022-05625-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 12/13/2022]
Abstract
We examined associations between prenatal oxidative stress (OS) and child autism-related outcomes. Women with an autistic child were followed through a subsequent pregnancy and that younger sibling's childhood. Associations between glutathione (GSH), glutathione disulfide (GSSG), 8-oxo-deoxyguanine (8-OHdG), and nitrotyrosine and younger sibling Social Responsiveness Scale (SRS) scores were examined using quantile regression. Increasing GSH:GSSG (suggesting decreasing OS) was associated with minor increases in SRS scores (50th percentile β: 1.78, 95% CI: 0.67, 3.06); no other associations were observed. Results from this cohort with increased risk for autism do not support a strong relationship between OS in late pregnancy and autism-related outcomes. Results may be specific to those with enriched autism risk; future work should consider other timepoints and biomarkers.
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Affiliation(s)
- Meghan E Carey
- A.J. Drexel Autism Institute, Drexel University, 3020 Market Street, Suite 560, Philadelphia, PA, 19104, United States.
| | - Juliette Rando
- A.J. Drexel Autism Institute, Drexel University, 3020 Market Street, Suite 560, Philadelphia, PA, 19104, United States
| | - Stepan Melnyk
- Arkansas Children's Hospital Research Institute, 13 Childrens Way, Little Rock, AR, 72202, United States
- Department of Pediatrics, University of Arkansas for Medical Sciences, 4301 W Markham St, Little Rock, AR, 72205, United States
| | - S Jill James
- Department of Pediatrics, University of Arkansas for Medical Sciences, 4301 W Markham St, Little Rock, AR, 72205, United States
| | - Nathaniel Snyder
- Lewis Katz School of Medicine, Temple University, 3500 N Broad St, Philadelphia, PA, 19140, United States
| | - Carolyn Salafia
- Department of Pathology, New York Methodist Hospital, 506 6th St, Brooklyn, NY, 11215, United States
| | - Lisa A Croen
- Division of Research, Kaiser Permanente Northern California, 2000 Broadway, Oakland, CA, 94612, United States
| | - M Daniele Fallin
- A.J. Drexel Autism Institute, Drexel University, 3020 Market Street, Suite 560, Philadelphia, PA, 19104, United States
| | - Irva Hertz-Picciotto
- Department of Public Health Sciences, University of California, 1 Shields Ave, Davis, CA, 95616, United States
| | - Heather Volk
- Department of Mental Health, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe St, Baltimore, MD, 21205, United States
| | - Craig Newschaffer
- College of Health and Human Development, The Pennsylvania State University, 325 Health and Human Development Building, University Park, State College, PA, 16802, United States
| | - Kristen Lyall
- A.J. Drexel Autism Institute, Drexel University, 3020 Market Street, Suite 560, Philadelphia, PA, 19104, United States
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Bock JM, Vungarala S, Karim S, Somers VK. Obstructive Sleep Apnea as a Cardiovascular Risk Factor-Beyond CPAP. Can J Cardiol 2021; 37:756-765. [PMID: 33610689 DOI: 10.1016/j.cjca.2021.01.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 01/28/2021] [Accepted: 01/31/2021] [Indexed: 12/14/2022] Open
Abstract
Patients with obstructive sleep apnea (OSA) experience repetitive partial or complete airway collapse during sleep resulting in nocturnal hypoxia-normoxia cycling, and are at increased cardiovascular risk. The number of apneas and hypopneas indexed per hour of sleep (apnea-hypopnea index) along with the associated intermittent hypoxia predict the increased cardiovascular risk; thus, their attenuation or prevention are objectives of OSA therapy. Continuous positive airway pressure (CPAP) is the gold standard treatment for OSA and, when effective, mitigates the apnea-hypopnea index and hypoxemia. As such, it is reasonable to expect CPAP would decrease cardiovascular risk. However, 3 recent randomized clinical trials of CPAP vs usual care did not show any significant effects of CPAP in attenuating incident cardiovascular events in patients with OSA. In this review, we discuss these studies in addition to potential complementary therapeutic options to CPAP (eg, neurostimulation) and conclude with suggested therapeutic targets for future interventional studies (eg, the autonomic nervous system). Although these areas of research are exciting, they have yet to be tested to any similar degree of rigour as CPAP.
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Affiliation(s)
- Joshua M Bock
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Soumya Vungarala
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Shahid Karim
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Virend K Somers
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA.
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Bandookwala M, Thakkar D, Sengupta P. Advancements in the Analytical Quantification of Nitroxidative Stress Biomarker 3-Nitrotyrosine in Biological Matrices. Crit Rev Anal Chem 2019; 50:265-289. [DOI: 10.1080/10408347.2019.1623010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Maria Bandookwala
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat, India
| | - Disha Thakkar
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat, India
| | - Pinaki Sengupta
- Department of Pharmaceutical Analysis, National Institute of Pharmaceutical Education and Research-Ahmedabad, Gandhinagar, Gujarat, India
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Xu H, Zheng X, Jia W, Yin S. Chromatography/Mass Spectrometry-Based Biomarkers in the Field of Obstructive Sleep Apnea. Medicine (Baltimore) 2015; 94:e1541. [PMID: 26448002 PMCID: PMC4616745 DOI: 10.1097/md.0000000000001541] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Biomarker assessment is based on quantifying several proteins and metabolites. Recent developments in proteomics and metabolomics have enabled detection of these small molecules in biological samples and exploration of the underlying disease mechanisms in obstructive sleep apnea (OSA). This systemic review was performed to identify biomarkers, which were only detected by chromatography and/or mass spectrometry (MS) and to discuss the role of these biomarkers in the field of OSA. We systemically reviewed relevant articles from PubMed and EMBASE referring to proteins and metabolite profiles of biological samples in patients with OSA. The analytical platforms in this review were focused on chromatography and/or MS. In total, 30 studies evaluating biomarkers in patients with OSA using chromatography and/or MS methods were included. Numerous proteins and metabolites, including lipid profiles, adrenergic/dopaminergic biomarkers and derivatives, amino acids, oxidative stress biomarkers, and other micromolecules were identified in patients with OSA. Applying chromatography and/or MS methods to detect biomarkers helps develop an understanding of OSA mechanisms. More proteomic and metabolomic studies are warranted to develop potential diagnostic and clinical monitoring methods for OSA.
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Affiliation(s)
- Huajun Xu
- From the Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China (HX, XZ, SY); and Center for Translational Medicine, and Shanghai Key Laboratory of Diabetes Mellitus, Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China (HX, XZ, WJ)
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A novel mixed-mode solid phase extraction coupled with LC–MS/MS for the re-evaluation of free 3-nitrotyrosine in human plasma as an oxidative stress biomarker. Talanta 2015; 140:45-51. [DOI: 10.1016/j.talanta.2015.02.053] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/10/2015] [Accepted: 02/15/2015] [Indexed: 01/20/2023]
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Nitric Oxide Bioavailability in Obstructive Sleep Apnea: Interplay of Asymmetric Dimethylarginine and Free Radicals. SLEEP DISORDERS 2015; 2015:387801. [PMID: 26064689 PMCID: PMC4438195 DOI: 10.1155/2015/387801] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 04/15/2015] [Accepted: 04/17/2015] [Indexed: 01/13/2023]
Abstract
Obstructive sleep apnea (OSA) occurs in 2% of middle-aged women and 4% of middle-aged men and is considered an independent risk factor for cerebrovascular and cardiovascular diseases. Nitric oxide (NO) is an important endothelium derived vasodilating substance that plays a critical role in maintaining vascular homeostasis. Low levels of NO are associated with impaired endothelial function. Asymmetric dimethylarginine (ADMA), an analogue of L-arginine, is a naturally occurring product of metabolism found in the human circulation. Elevated levels of ADMA inhibit NO synthesis while oxidative stress decreases its bioavailability, so impairing endothelial function and promoting atherosclerosis. Several clinical trials report increased oxidative stress and ADMA levels in patients with OSA. This review discusses the role of oxidative stress and increased ADMA levels in cardiovascular disease resulting from OSA.
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Verrastro I, Pasha S, Jensen KT, Pitt AR, Spickett CM. Mass spectrometry-based methods for identifying oxidized proteins in disease: advances and challenges. Biomolecules 2015; 5:378-411. [PMID: 25874603 PMCID: PMC4496678 DOI: 10.3390/biom5020378] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/20/2015] [Accepted: 03/23/2015] [Indexed: 01/02/2023] Open
Abstract
Many inflammatory diseases have an oxidative aetiology, which leads to oxidative damage to biomolecules, including proteins. It is now increasingly recognized that oxidative post-translational modifications (oxPTMs) of proteins affect cell signalling and behaviour, and can contribute to pathology. Moreover, oxidized proteins have potential as biomarkers for inflammatory diseases. Although many assays for generic protein oxidation and breakdown products of protein oxidation are available, only advanced tandem mass spectrometry approaches have the power to localize specific oxPTMs in identified proteins. While much work has been carried out using untargeted or discovery mass spectrometry approaches, identification of oxPTMs in disease has benefitted from the development of sophisticated targeted or semi-targeted scanning routines, combined with chemical labeling and enrichment approaches. Nevertheless, many potential pitfalls exist which can result in incorrect identifications. This review explains the limitations, advantages and challenges of all of these approaches to detecting oxidatively modified proteins, and provides an update on recent literature in which they have been used to detect and quantify protein oxidation in disease.
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Affiliation(s)
- Ivan Verrastro
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK.
| | - Sabah Pasha
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK.
| | - Karina Tveen Jensen
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK.
| | - Andrew R Pitt
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK.
| | - Corinne M Spickett
- School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, B4 7ET, UK.
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Tsikas D, Duncan MW. Mass spectrometry and 3-nitrotyrosine: strategies, controversies, and our current perspective. MASS SPECTROMETRY REVIEWS 2014; 33:237-76. [PMID: 24167057 DOI: 10.1002/mas.21396] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 06/24/2013] [Accepted: 06/24/2013] [Indexed: 05/11/2023]
Abstract
Reactive-nitrogen species (RNS) such as peroxynitrite (ONOO(-)), that is, the reaction product of nitric oxide ((•)NO) and superoxide (O2(-•)), nitryl chloride (NO2Cl) and (•)NO2 react with the activated aromatic ring of tyrosine to form 3-nitrotyrosine. This modification, which has been known for more than a century, occurs to both the free form of the amino acid (i.e., soluble/free tyrosine) and to tyrosine residues covalently bound within the backbone of peptides and proteins. Nitration of tyrosine is thought to be of biological significance and has been linked to health and disease, but determining its role has proved challenging. Several key questions have been the focus of much of the research activity: (a) to what extent is free/soluble tyrosine nitrated in biological tissues and fluids, and (b) are there specific site(s) of nitration within peptides/proteins and to what extent (i.e., stoichiometry) does this modification occur? These issues have been addressed in a wide range of sample types (e.g., blood, urine, CSF, exhaled breath condensate and various tissues) and a diverse array of physiological/pathophysiological scenarios. The accurate determination of nitrated tyrosine is, however, a stumbling block. Despite extensive study, the extent to which nitration occurs in vivo, the specificity of the nitration reaction, and its importance in health and disease, remain unclear. In this review, we highlight the analytical challenges and discuss the approaches adopted to address them. Mass spectrometry, in combination with either gas chromatography (GC-MS, GC-MS/MS) or liquid chromatography (LC-MS/MS), has played the central role in the analysis of 3-nitrotyrosine and tyrosine-nitrated biological macromolecules. We discuss its unique attributes and highlight the role of stable-isotope labeled 3-nitrotyrosine analogs in both accurate quantification, and in helping to define the biological relevance of tyrosine nitration. We show that the application of sophisticated mass spectrometric techniques is advantageous if not essential, but that this alone is by no means a guarantee of accurate findings. We discuss the important analytical challenges in quantifying 3-nitrotyrosine, possible workarounds, and we attempt to make sense of the disparate findings that have been reported so far.
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Affiliation(s)
- Dimitrios Tsikas
- Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany
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Badran M, Golbidi S, Devlin A, Ayas N, Laher I. Chronic intermittent hypoxia causes endothelial dysfunction in a mouse model of diet-induced obesity. Sleep Med 2014; 15:596-602. [DOI: 10.1016/j.sleep.2014.01.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 01/25/2014] [Accepted: 01/30/2014] [Indexed: 11/16/2022]
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Cardiovascular complications of sleep apnea: role of oxidative stress. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:985258. [PMID: 24734153 PMCID: PMC3964889 DOI: 10.1155/2014/985258] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 01/30/2014] [Indexed: 01/07/2023]
Abstract
Obstructive sleep apnea (OSA) occurs in 2% of middle-aged women and 4% of middle-aged men with a higher prevalence among obese subjects. This condition is considered as an independent risk factor for cerebrovascular and cardiovascular diseases. One of the major pathophysiological characteristics of OSA is intermittent hypoxia. Hypoxia can lead to oxidative stress and overproduction of reactive oxygen species, which can lead to endothelial dysfunction, a hallmark of atherosclerosis. Many animal models, such as the rodent model of intermittent hypoxia, mimic obstructive sleep apnea in human patients and allow more in-depth investigation of biological and cellular mechanisms of this condition. This review discusses the role of oxidative stress in cardiovascular disease resulting from OSA in humans and animal models.
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Renal vasodilating capacity and endothelial function are impaired in patients with obstructive sleep apnea syndrome and no traditional cardiovascular risk factors. J Hypertens 2014; 31:1456-64; discussion 1464. [PMID: 23965549 DOI: 10.1097/hjh.0b013e328360f773] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Patients with obstructive sleep apnea syndrome exhibit accelerated vascular aging and renal damage. Aim of the study was to investigate whether vascular dysfunction is a feature of obstructive sleep apnea syndrome per se or instead related to the presence of traditional cardiovascular risk factors. METHODS Forty patients with moderate-severe obstructive sleep apnea syndrome (20 with, 20 without traditional risk factors) and 20 matched healthy controls were enrolled. Renal vasodilating capacity, endothelium-dependent vasodilation in the brachial artery, carotid-femoral pulse wave velocity and carotid stiffness were measured. Oxidative stress, endothelial biomarkers and leukocyte adhesion molecule levels were also evaluated. RESULTS Apneic patients without traditional cardiovascular risk factors presented reduced endothelium-dependent vasodilation (3.7±2.1 versus 6.1±3.0%, P<0.05), increased serum E-selectin (49.8±11.5 versus 38.9±17.9 ng/ml, P<0.05), and impaired renal vasodilating capacity (6.0±4.3 versus 10.4±6.1%, P<0.05), as compared to healthy controls. Endothelial NO synthase expression was reduced (0.0133 versus 0.0221×10 copies/μg RNA, P<0.05), whereas oxidative stress parameters and leukocyte adhesion molecules were similar to controls. Patients with obstructive sleep apnea syndrome and traditional risk factors also exhibit increased aortic and carotid stiffness, increased renal resistive index and intima-media thickness, and reduced expression of the endothelial progenitor cell marker CD34: however, these parameters were similar to those of healthy controls in patients with isolated obstructive sleep apnea syndrome. CONCLUSION Obstructive sleep apnea syndrome is characterized by endothelial dysfunction and activation and impaired renal vasodilating capacity even in the absence of traditional cardiovascular risk factors, possibly due to reduced endothelial NO synthase expression.
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Badran M, Ayas N, Laher I. Insights into obstructive sleep apnea research. Sleep Med 2014; 15:485-95. [PMID: 24824769 DOI: 10.1016/j.sleep.2014.01.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 01/03/2014] [Accepted: 01/08/2014] [Indexed: 01/11/2023]
Abstract
Moderate to severe obstructive sleep apnea (OSA) occurs in 10-17% of middle aged men and 3-9% of middle-aged women with a higher prevalence among obese subjects. This condition is an independent risk factor for many cardiovascular diseases. Intermittent hypoxia is a major pathophysiologic character of OSA; it can lead to oxidative stress and inflammation, which in their turn cause endothelial dysfunction, a hallmark of atherosclerosis. Many animal models have been designed to mimic OSA in human patients to allow more in-depth investigation of biological and cellular mechanisms of this condition. This review discusses the cardiovascular outcomes of OSA and some of the animal models that are being used to investigate it.
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Affiliation(s)
- Mohammad Badran
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Najib Ayas
- Divisions of Critical Care and Respiratory Medicine, Department of Medicine, University of British Columbia, Sleep Disorders Program, UBC Hospital, Division of Critical Care Medicine, Providence Health Care, Vancouver, BC, Canada
| | - Ismail Laher
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
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Tahrani AA, Ali A. Oxidative Stress, Inflammation and Endothelial Dysfunction: The Link Between Obstructive Sleep Apnoea and Vascular Disease in Type 2 Diabetes. OXIDATIVE STRESS IN APPLIED BASIC RESEARCH AND CLINICAL PRACTICE 2014:149-171. [DOI: 10.1007/978-1-4899-8035-9_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Stanke-Labesque F, Pépin JL, Gautier-Veyret E, Lévy P, Bäck M. Leukotrienes as a molecular link between obstructive sleep apnoea and atherosclerosis. Cardiovasc Res 2013; 101:187-93. [DOI: 10.1093/cvr/cvt247] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Activation of heme oxygenase and suppression of cGMP are associated with impaired endothelial function in obstructive sleep apnea with hypertension. Am J Hypertens 2012; 25:854-61. [PMID: 22647785 DOI: 10.1038/ajh.2012.56] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Obstructive sleep apnea (OSA) is a highly prevalent disorder that increases the risk of systemic hypertension and cardiovascular diseases. Heme oxygenase (HO) has been shown to be upregulated in patients with OSA and its overexpression in mice causes hypertension. End products of HO are carbon monoxide (CO) and bilirubin. CO exerts a pleiotropic action on vasoregulation. Despite high prevalence and incident of hypertension in OSA, its pathophysiology is not well-understood, particularly in regard to varying susceptibility of patients to hypertension. We investigated the role of HO in endothelial dysfunction and hypertension in OSA. METHODS We determined flow-mediated vasodilatation (FMD) as a measure of endothelial-dependent vasodilatory capacity, exhaled CO, bilirubin, and guanosine 3',5'-cyclic monophosphate (cGMP) in 63 subjects with OSA (normotensive 27, hypertensive 36) and in 32 subjects without OSA (normotensive 19, hypertensive 13). RESULTS Hypertensive OSA demonstrated marked impairment in FMD (8.0 ± 0.5% vasodilatation) compared to 10.5 ± 0.8% in hypertensives non-OSA (P < 0.01) and 13.5 ± 0.5% in normotensive OSA (P < 0.001) and 16.1 ± 1.1% in normotensive non-OSA (P < 0.0001). HO was upregulated and plasma nitric oxide (NO) was significantly increased in hypertensive OSA compared to normotensive OSA and hypertensive non-OSA. Conversely, serum cGMP was markedly decreased in hypertensive OSA (12.9 ± 1.8 pmol/ml vs. 20.6 ± 3.7 in normotensive OSA, P = 0.032). There was an inverse relationship between FMD and CO and bilirubin concentrations (r = 0.43, P = 0.0001 and r = 0.28, P = 0.01, respectively). CONCLUSIONS These data show that increased CO in the setting of elevated NO concentrations is associated with decreased cGMP, impaired FMD, and hypertension in patient with OSA.
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Duncan MW. Good mass spectrometry and its place in good science. JOURNAL OF MASS SPECTROMETRY : JMS 2012; 47:795-809. [PMID: 22707172 DOI: 10.1002/jms.3038] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The mass spectrometry community has expanded as instruments became more powerful, user-friendly, affordable and readily available. This opens up opportunities for novice users to perform high impact research, using highly advanced instrumentation. This introductory tutorial is targeted at the novice user working in a research setting. It aims to offer the benefit of other people's experiences and to help newcomers avoid known pitfalls and problematic issues. It discusses some of the essential features of sound analytical chemistry and highlights the need to use validated analytical methods that provide high quality results along with a measure of their uncertainty. Examples are used to illustrate potential pitfalls and their consequences.
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Affiliation(s)
- Mark W Duncan
- Division of Endocrinology, Metabolism and Diabetes, Department of Medicine, University of Colorado Denver-School of Medicine, Aurora, Colorado 80045, USA.
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Weber D, Kneschke N, Grimm S, Bergheim I, Breusing N, Grune T. Rapid and sensitive determination of protein-nitrotyrosine by ELISA: Application to human plasma. Free Radic Res 2012; 46:276-85. [PMID: 22276750 DOI: 10.3109/10715762.2011.652627] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
3-Nitrotyrosine (3NT) is known as an important indicator of nitrosative stress and has been linked to various diseases. Our aim was to develop an indirect ELISA (enzyme-linked immunosorbent assay) method suitable for the detection of protein-bound 3NT in clinical plasma and serum samples. Nitrated protein standards and reduced protein standards were prepared. Limit of detection was determined for standards; recovery and reproducibility were determined for human plasma samples. The limit of detection for this method is 1.82±0.56 pmol/mg protein. Mean recovery of standards was 95%. 3NT concentration in plasma samples of obese and normal weight subjects was determined to be between 2 pmol/mg and 19 pmol/mg. No time-consuming sample preparation or expensive laboratory equipment is required, and applied antibodies are commercially available. Sensitivity, rapid analysis time, possibilities of high throughput applications and small sample volumes make this ELISA attractive for use in clinical laboratories.
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Affiliation(s)
- Daniela Weber
- Institute of Nutrition, Department of Nutritional Toxicology, Friedrich Schiller University of Jena, Dornburger Strasse 24, Jena, Germany
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Golbidi S, Badran M, Ayas N, Laher I. Cardiovascular consequences of sleep apnea. Lung 2011; 190:113-32. [PMID: 22048845 DOI: 10.1007/s00408-011-9340-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 10/03/2011] [Indexed: 12/25/2022]
Abstract
Sleep apnea is a common health concern that is characterized by repetitive episodes of asphyxia. This condition has been linked to serious long-term adverse effects such as hypertension, metabolic dysregulation, and cardiovascular disease. Although the mechanism for the initiation and aggravation of cardiovascular disease has not been fully elucidated, oxidative stress and subsequent endothelial dysfunction play major roles. Animal models, which have the advantage of being free of comorbidities and/or behavioral variables (that commonly occur in humans), allow invasive measurements under well-controlled experimental conditions, and as such are useful tools in the study of the pathophysiological mechanisms of sleep apnea. This review summarizes currently available information on the cardiovascular consequences of sleep apnea and briefly describes common experimental approaches useful to sleep apnea in different animal models.
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Affiliation(s)
- Saeid Golbidi
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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Feng J, Zhang D, Chen B. Endothelial mechanisms of endothelial dysfunction in patients with obstructive sleep apnea. Sleep Breath 2011; 16:283-94. [PMID: 21479903 DOI: 10.1007/s11325-011-0519-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/23/2011] [Accepted: 03/30/2011] [Indexed: 12/12/2022]
Abstract
BACKGROUND Obstructive sleep apnea (OSA) occurs in 2% of middle-aged women and 4% of middle-aged men in the general population and the prevalence is much higher in specific patient groups. Intermittent hypoxia (IH, oxygen desaturation and re-oxygenation) cycle, a major pathophysiologic character of OSA, and the physiological responses this evokes are thought to be responsible for its association with increased cardiovascular morbidity and mortality. Endothelial dysfunction, resulting from IH and as a key early event in atherosclerosis, was demonstrated repeatedly in patients with OSA and in animal models of IH, providing an important mechanistic link between the acute cyclical IH during sleep and the increased prevalence of chronic vascular diseases. CONCLUSIONS From this work, we conclude that IH from OSA may result in endothelial dysfunction, as a potential promoter of atherosclerosis, through nitric oxide unavailability, oxidative stress and inflammation, cell apoptosis, the crosstalk between endothelial cells and circulating inflammatory cells, microparticles, and damage repairing process. Though effective continuous positive airway pressure (CPAP) may specifically improve endothelial function, more controlled larger interventional trials that will include multiple centers and randomized allocation of CPAP therapy are needed to see if such changes are reversible before cause and effect can be implied finally, while further studies on cellular and animal level are also needed to elucidate molecular biologic/pathologic pathways.
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Affiliation(s)
- Jing Feng
- Respiratory Department of Tianjin Medical University General Hospital, Tianjin, 300052, China
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21
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Katsoulis K, Kontakiotis T, Spanogiannis D, Vlachogiannis E, Kougioulis M, Gerou S, Daskalopoulou E. Total antioxidant status in patients with obstructive sleep apnea without comorbidities: the role of the severity of the disease. Sleep Breath 2011; 15:861-6. [PMID: 21267664 DOI: 10.1007/s11325-010-0456-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 11/06/2010] [Accepted: 11/26/2010] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Several studies suggest that obstructive sleep apnea syndrome (OSAS) is associated with oxidative stress. However, there are also contrary observations and the role of antioxidant mechanisms has not been fully explored. PATIENTS AND METHODS The present study evaluated serum total antioxidant status (TAS) in 32 OSAS patients without comorbidities, before and after a diagnostic sleep study and at a second sleep study after continuous positive airway pressure (CPAP) application. RESULTS Lower TAS values were found in the morning, immediately after the first sleep study, compared with those before sleep (1.68 ± 0.11 vs. 1.61 ± 0.10 mmol/l, p < 0.01); this was evident in patients with less severe syndrome [apnea-hypopnea index (AHI) <30; 1.73 ± 0.08 vs. 1.65 ± 0.09 mmol/l, p = 0.01] but not in severe syndrome (AHI ≥30; 1.64 ± 0.12 vs. 1.58 ± 0.10 mmol/l, p = 0.07). After CPAP application, a statistically significant decrease in TAS values was observed in patients with less severe syndrome (1.72 ± 0.05 vs. 1.63 ± 0.04 mmol/l, p = 0.003). On the contrary, no statistically significant changes in TAS were observed in patients with severe syndrome. CONCLUSIONS The present study supports a reduction in antioxidant capacity during sleep in otherwise healthy patients with OSAS. This reduction was evident in less severe syndrome. However, a single night of CPAP application seems to ameliorate this antioxidant disturbance only in less severe syndrome.
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Affiliation(s)
- Kostas Katsoulis
- Pulmonary & Microbiology Department, General Army Hospital, Thessaloniki, Greece
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22
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Analytical methods for 3-nitrotyrosine quantification in biological samples: the unique role of tandem mass spectrometry. Amino Acids 2010; 42:45-63. [DOI: 10.1007/s00726-010-0604-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2010] [Accepted: 04/16/2010] [Indexed: 12/31/2022]
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Abstract
Endothelial activation and inflammation are important mediators of accelerated atherogenesis and consequent increased cardiovascular morbidity in obstructive sleep apnea (OSA). Repetitive episodes of hypoxia/reoxygenation associated with transient cessation of breathing during sleep in OSA resemble ischemia/reperfusion injury and may be the main culprit underlying endothelial dysfunction in OSA. Additional factors such as repetitive arousals resulting in sleep fragmentation and deprivation and individual genetic suseptibility to vascular manifestations of OSA contribute to impaired endothelial function in OSA. The present review focuses on possible mechanisms that underlie endothelial activation and inflammation in OSA.
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Affiliation(s)
- Amy Atkeson
- Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, 630 West 168th Street, New York, NY 10032, USA
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Abstract
Untreated obstructive sleep apnea (OSA) is an independent risk factor for hypertension, myocardial infarction, and stroke. The repetitive hypoxia/reoxygenation and sleep fragmentation associated with OSA impair endothelial function. Endothelial dysfunction, in turn, may mediate increased risk for cardiovascular diseases. Specifically, in OSA, endothelial nitric oxide availability and repair capacity are reduced, whereas oxidative stress and inflammation are enhanced. Treatment of OSA improves endothelial vasomotor tone and reduces inflammation. We review the evidence and possible mechanisms of endothelial dysfunction as well as the effect of treatment on endothelial function in OSA.
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Affiliation(s)
- Amy Atkeson
- Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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Abstract
There is increasing evidence of a causal relationship between sleep-disordered breathing and metabolic dysfunction. Metabolic syndrome (MetS), a cluster of risk factors that promote atherosclerotic cardiovascular disease, comprises central obesity, insulin resistance, glucose intolerance, dyslipidemia, and hypertension, manifestations of altered total body energy regulation. Excess caloric intake is indisputably the key driver of MetS, but other environmental and genetic factors likely play a role; in particular, obstructive sleep apnea (OSA), characterized by intermittent hypoxia (IH), may induce or exacerbate various aspects of MetS. Clinical studies show that OSA can affect glucose metabolism, cholesterol, inflammatory markers, and nonalcoholic fatty liver disease. Animal models of OSA enable scientists to circumvent confounders such as obesity in clinical studies. In the most widely used model, which involves exposing rodents to IH during their sleep phase, the IH alters circadian glucose homeostasis, impairs muscle carbohydrate uptake, induces hyperlipidemia, and upregulates cholesterol synthesis enzymes. Complicating factors such as obesity or a high-fat diet lead to progressive insulin resistance and liver inflammation, respectively. Mechanisms for these effects are not yet fully understood, but are likely related to energy-conserving adaptations to hypoxia, which is a strong catabolic stressor. Finally, IH may contribute to the morbidity of MetS by inducing inflammation and oxidative stress. Identification of OSA as a potential causative factor in MetS would have immense clinical impact and could improve the management and understanding of both disorders.
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Affiliation(s)
- Jonathan Jun
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
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Jelic S, Le Jemtel TH. Inflammation, Oxidative Stress, and the Vascular Endothelium in Obstructive Sleep Apnea. Trends Cardiovasc Med 2008; 18:253-60. [DOI: 10.1016/j.tcm.2008.11.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 11/19/2008] [Accepted: 11/21/2008] [Indexed: 10/21/2022]
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Khayat R, Patt B, Hayes D. Obstructive sleep apnea: the new cardiovascular disease. Part I: Obstructive sleep apnea and the pathogenesis of vascular disease. Heart Fail Rev 2008; 14:143-53. [PMID: 18807180 DOI: 10.1007/s10741-008-9112-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Accepted: 08/12/2008] [Indexed: 12/21/2022]
Abstract
Obstructive sleep apnea (OSA) is increasingly recognized as a novel cardiovascular risk factor. OSA is implicated in the pathogenesis of hypertension, left ventricular dysfunction, coronary artery disease and stroke. OSA exerts its negative cardiovascular consequences through its unique pattern of intermittent hypoxia. Endothelial dysfunction, oxidative stress, and inflammation are all consequences of OSA directly linked to intermittent hypoxia and critical pathways in the pathogenesis of cardiovascular disease in patients with OSA. This review will discuss the known mechanisms of vascular dysfunction in patients with OSA and their implications for cardiovascular disease.
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Affiliation(s)
- Rami Khayat
- The Ohio State University Sleep Heart Program, The Ohio State University, 473 W 12th Ave, Suite 105, Columbus, OH 43210, USA
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Somers VK, White DP, Amin R, Abraham WT, Costa F, Culebras A, Daniels S, Floras JS, Hunt CE, Olson LJ, Pickering TG, Russell R, Woo M, Young T. Sleep apnea and cardiovascular disease: an American Heart Association/American College of Cardiology Foundation Scientific Statement from the American Heart Association Council for High Blood Pressure Research Professional Education Committee, Council on Clinical Cardiology, Stroke Council, and Council on Cardiovascular Nursing. J Am Coll Cardiol 2008; 52:686-717. [PMID: 18702977 DOI: 10.1016/j.jacc.2008.05.002] [Citation(s) in RCA: 601] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
MESH Headings
- Adult
- Arrhythmias, Cardiac/epidemiology
- Cardiovascular Diseases/epidemiology
- Cardiovascular Diseases/physiopathology
- Child
- Comorbidity
- Continuous Positive Airway Pressure
- Death, Sudden, Cardiac
- Disease Progression
- Endothelium, Vascular/physiopathology
- Heart Failure/epidemiology
- Heart Rate/physiology
- Humans
- Hypertension/physiopathology
- Hypertension, Pulmonary/epidemiology
- Hypertension, Pulmonary/physiopathology
- Hypertrophy, Left Ventricular/epidemiology
- Hypoxia/physiopathology
- Insulin Resistance/physiology
- Kidney Failure, Chronic/epidemiology
- Kidney Failure, Chronic/physiopathology
- Myocardial Ischemia/epidemiology
- Myocardial Ischemia/physiopathology
- Obesity/epidemiology
- Oxidative Stress/physiology
- Polysomnography
- Sleep Apnea, Central/diagnosis
- Sleep Apnea, Central/epidemiology
- Sleep Apnea, Central/physiopathology
- Sleep Apnea, Obstructive/diagnosis
- Sleep Apnea, Obstructive/epidemiology
- Sleep Apnea, Obstructive/physiopathology
- Sleep Apnea, Obstructive/therapy
- Stroke/epidemiology
- Sympathetic Nervous System/physiopathology
- Ventricular Dysfunction, Left/epidemiology
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Somers VK, White DP, Amin R, Abraham WT, Costa F, Culebras A, Daniels S, Floras JS, Hunt CE, Olson LJ, Pickering TG, Russell R, Woo M, Young T. Sleep apnea and cardiovascular disease: an American Heart Association/american College Of Cardiology Foundation Scientific Statement from the American Heart Association Council for High Blood Pressure Research Professional Education Committee, Council on Clinical Cardiology, Stroke Council, and Council On Cardiovascular Nursing. In collaboration with the National Heart, Lung, and Blood Institute National Center on Sleep Disorders Research (National Institutes of Health). Circulation 2008. [PMID: 18725495 DOI: 10.1161/circulationaha.107.189420] [Citation(s) in RCA: 801] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Jun J, Savransky V, Nanayakkara A, Bevans S, Li J, Smith PL, Polotsky VY. Intermittent hypoxia has organ-specific effects on oxidative stress. Am J Physiol Regul Integr Comp Physiol 2008; 295:R1274-81. [PMID: 18703411 DOI: 10.1152/ajpregu.90346.2008] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Obstructive sleep apnea is characterized by upper airway collapse, leading to intermittent hypoxia (IH). It has been postulated that IH-induced oxidative stress may contribute to several chronic diseases associated with obstructive sleep apnea. We hypothesize that IH induces systemic oxidative stress by upregulating NADPH oxidase, a superoxide-generating enzyme. NADPH oxidase is regulated by a cytosolic p47(phox) subunit, which becomes phosphorylated during enzyme activation. Male C57BL/6J mice were exposed to IH with an inspired O(2) fraction nadir of 5% 60 times/h during the 12-h light phase (9 AM-9 PM) for 1 or 4 wk. In the aorta and heart, IH did not affect lipid peroxidation [malondialdehyde (MDA) level], nitrotyrosine level, or p47(phox) expression and phosphorylation. In contrast, in the liver, exposure to IH for 1 wk resulted in a trend to an increase in MDA levels, whereas IH for 4 wk resulted in a 38% increase in MDA levels accompanied by upregulation of p47(phox) expression and phosphorylation. Administration of an NADPH oxidase inhibitor, apocynin, during IH exposure attenuated IH-induced increases in hepatic MDA. In p47(phox)-deficient mice, MDA levels were higher at baseline and, unexpectedly, decreased during IH. In conclusion, oxidative stress levels and pathways under IH conditions are organ and duration specific.
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Affiliation(s)
- Jonathan Jun
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD 21224, USA.
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A critical review and discussion of analytical methods in the l-arginine/nitric oxide area of basic and clinical research. Anal Biochem 2008; 379:139-63. [DOI: 10.1016/j.ab.2008.04.018] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Revised: 04/08/2008] [Accepted: 04/09/2008] [Indexed: 12/21/2022]
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32
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Mehra R, Redline S. Sleep apnea: a proinflammatory disorder that coaggregates with obesity. J Allergy Clin Immunol 2008; 121:1096-102. [PMID: 18466782 DOI: 10.1016/j.jaci.2008.04.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2008] [Revised: 04/01/2008] [Accepted: 04/03/2008] [Indexed: 11/26/2022]
Abstract
Both obesity and sleep apnea are prevalent health conditions that frequently coaggregate. Obesity-associated inflammation may influence asthma control; the relation of sleep apnea to asthma or allergic rhinitis may be bidirectional. Both obesity and sleep apnea are associated with augmented levels of inflammation and oxidative stress, and it is biologically plausible that the proinflammatory effects of one disorder influence the expression of the other disorder. This article elucidates mechanistic associations among obesity, sleep apnea, and systemic inflammation; highlights interrelationships between these factors with cardiopulmonary disease; and identifies specific areas for future research directions.
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Affiliation(s)
- Reena Mehra
- Department of Medicine, Case Comprehensive Cancer Center, Case School of Medicine, Cleveland, OH 44106-6003, USA.
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33
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Lopez-Jimenez F, Sert Kuniyoshi FH, Gami A, Somers VK. Obstructive sleep apnea: implications for cardiac and vascular disease. Chest 2008; 133:793-804. [PMID: 18321908 DOI: 10.1378/chest.07-0800] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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34
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Jelic S, Padeletti M, Kawut SM, Higgins C, Canfield SM, Onat D, Colombo PC, Basner RC, Factor P, LeJemtel TH. Inflammation, oxidative stress, and repair capacity of the vascular endothelium in obstructive sleep apnea. Circulation 2008; 117:2270-8. [PMID: 18413499 DOI: 10.1161/circulationaha.107.741512] [Citation(s) in RCA: 402] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Indirect evidence implicates endothelial dysfunction in the pathogenesis of vascular diseases associated with obstructive sleep apnea (OSA). We investigated directly whether dysfunction and inflammation occur in vivo in the vascular endothelium of patients with OSA. The effects of continuous positive airway pressure (CPAP) therapy on endothelial function and repair capacity were assessed. METHODS AND RESULTS Thirty-two patients with newly diagnosed OSA and 15 control subjects were studied. Proteins that regulate basal endothelial nitric oxide (NO) production (endothelial NO synthase [eNOS] and phosphorylated eNOS) and inflammation (cyclooxygenase-2 and inducible NOS) and markers of oxidative stress (nitrotyrosine) were quantified by immunofluorescence in freshly harvested venous endothelial cells before and after 4 weeks of CPAP therapy. Vascular reactivity was measured by flow-mediated dilation. Circulating endothelial progenitor cell levels were quantified to assess endothelial repair capacity. Baseline endothelial expression of eNOS and phosphorylated eNOS was reduced by 59% and 94%, respectively, in patients with OSA compared with control subjects. Expression of both nitrotyrosine and cyclooxygenase-2 was 5-fold greater in patients with OSA than in control subjects, whereas inducible NOS expression was 56% greater. Expression of eNOS and phosphorylated eNOS significantly increased, whereas expression of nitrotyrosine, cyclooxygenase-2, and inducible NOS significantly decreased in patients who adhered to CPAP > or = 4 hours daily. Baseline flow-mediated dilation and endothelial progenitor cell levels were lower in patients than in control subjects, and both significantly increased in patients who adhered to CPAP > or = 4 hours daily. CONCLUSIONS OSA directly affects the vascular endothelium by promoting inflammation and oxidative stress while decreasing NO availability and repair capacity. Effective CPAP therapy is associated with the reversal of these alterations.
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Affiliation(s)
- Sanja Jelic
- Columbia University College of Physicians and Surgeons, Division of Pulmonary, Allergy, and Critical Care Medicine, PH8 Center, Room 840, 630 W 168th St, New York, NY 10032, USA.
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35
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Rabbani N, Thornalley PJ. Assay of 3-nitrotyrosine in tissues and body fluids by liquid chromatography with tandem mass spectrometric detection. Methods Enzymol 2008; 440:337-59. [PMID: 18423229 DOI: 10.1016/s0076-6879(07)00822-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
3-Nitrotyrosine (3-NT) is a marker of protein nitration in physiological systems. It is present as 3-nitrotyrosine residues in proteins of tissue, extracellular matrix, plasma, and other body fluids and food. It is also present in body fluids and some beverages as free nitrotyrosine and is excreted in urine with the major urinary metabolite 3-nitro-4-hydroxyphenylacetic acid. Quantitation of 3-nitrotyrosine requires tandem mass spectrometry for specific detection. The method developed to determine 3-nitrotyrosine (along with protein glycation and oxidation adducts in a quantitative screening assay) by liquid chromatography with tandem mass spectrometric detection is described. The 3-NT residue contents of plasma protein, hemoglobin, lipoproteins, and cerebrospinal fluid protein and the concentrations of free 3-nitrotyrosine in plasma, urine, and cerebrospinal fluid are given. Changes of 3-nitrotyrosine residue and free 3-nitrotyrosine in diabetes, cirrhosis, acute and chronic renal failure, and neurological disorders, including Alzheimer's disease, are presented and compared with independent estimates.
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Affiliation(s)
- Naila Rabbani
- Protein Damage and Systems Biology Research Group, Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, University Hospital, Coventry, United Kingdom
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36
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Gozal D, Kheirandish-Gozal L. Cardiovascular morbidity in obstructive sleep apnea: oxidative stress, inflammation, and much more. Am J Respir Crit Care Med 2007; 177:369-75. [PMID: 17975198 DOI: 10.1164/rccm.200608-1190pp] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Sleep-disordered breathing and obstructive sleep apnea (OSA) are highly prevalent disorders throughout the lifespan, which may affect up to 2-10% of the population, and have now been firmly associated with an increased risk for cardiovascular and neurobehavioral complications. Nevertheless, the overall pathophysiologic mechanisms mediating end-organ injury in OSA remain undefined, particularly due to the very frequent coexistence of other disease states, such as obesity, that clearly complicate the potential cause-effect relationships. Two major, and to some extent overlapping, mechanisms have been proposed to explain the morbid consequences of OSA, namely increased generation and propagation of reactive oxygen species and initiation and amplification of inflammatory processes. The evidence supporting the validity of these concepts as well as that detracting from such mechanisms will be critically reviewed in the context of clinical and laboratory-based approaches. In addition, some of the contradictory issues raised by such evaluation of the literature will be interpreted in the context of putative modifications of the individual responses to OSA, as determined by genetic variants among susceptibility-related genes, and also by potential environmental modulators of the phenotypic expression of any particular end-organ morbidity associated with OSA.
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Affiliation(s)
- David Gozal
- Kosair Children's Hospital Research Institute, University of Louisville School of Medicine, 570 South Preston Street, Suite 204, Louisville, KY 40202, USA.
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Foresi A, Leone C, Olivieri D, Cremona G. Alveolar-derived exhaled nitric oxide is reduced in obstructive sleep apnea syndrome. Chest 2007; 132:860-7. [PMID: 17646233 DOI: 10.1378/chest.06-3124] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Obstructive sleep apnea syndrome (OSAS) is associated with cardiovascular diseases, in particular systemic arterial hypertension. We postulated that intermittent nocturnal hypoxia in OSAS may be associated to decreased fractional exhaled nitric oxide (FENO) levels from distal airspaces. METHODS Multiple flow rate measurements have been used to fractionate nitric oxide (NO) from alveolar and bronchial sources in 34 patients with OSAS, in 29 healthy control subjects, and in 8 hypertensive non-OSAS patients. The effect of 2 days of treatment with nasal continuous positive airway pressure (nCPAP) on FENO was examined in 18 patients with severe OSAS. RESULTS We found that the mean [+/- SE] concentrations of exhaled NO at a rate of 50 mL/s was 21.8 +/- 1.9 parts per billion (ppb) in patients with OSAS, 25.1 +/- 3.3 ppb in healthy control subjects, and 15.4 +/- 1.7 ppb in hypertensive control patients. The mean fractional alveolar NO concentration (CANO) in OSAS patients was significantly lower than that in control subjects (2.96 +/- 0.48 vs 5.35 +/- 0.83 ppb, respectively; p < 0.05). In addition, CANO values were significantly lower in OSAS patients with systemic hypertension compared to those in normotensive OSAS patients and hypertensive patients without OSAS. The mean values of CANO significantly improved after nCPAP therapy (2.67 +/- 0.41 to 4.69 +/- 0.74 nL/L, respectively; p = 0.01). CONCLUSIONS These findings suggest that alveolar FENO, and not bronchial FENO, is impaired in patients with OSAS and that this impairment is associated with an increased risk of hypertension. NO production within the alveolar space is modified by treatment with nCPAP.
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Affiliation(s)
- Antonio Foresi
- Unit of Respiratory Medicine, Sesto San Giovanni Hospital, Sesto San Giovanni, Italy
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38
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Ptolemy AS, Lee R, Britz-McKibbin P. Strategies for comprehensive analysis of amino acid biomarkers of oxidative stress. Amino Acids 2007; 33:3-18. [PMID: 17514495 DOI: 10.1007/s00726-007-0542-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Accepted: 03/03/2007] [Indexed: 12/17/2022]
Abstract
Despite the wide interest in using modified amino acids as putative biomarkers of oxidative stress, many issues remain as to their overall reliability for early detection and diagnosis of diseases. In contrast to conventional single biomarker studies, comprehensive analysis of biomarkers offers an unbiased strategy for global assessment of modified amino acid metabolism due to reactive oxygen and nitrogen species. This review examines recent analytical techniques amenable for analysis of modified amino acids in biological samples reported during 2003-2007. Particular attention is devoted to the need for validated methods applicable to high-throughput analysis of multiple amino acid biomarkers, as well as consideration of sample pretreatment protocols on artifact formation for improved clinical relevance.
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Affiliation(s)
- A S Ptolemy
- Department of Chemistry, McMaster University, Hamilton, Ontario, Canada
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39
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Ryberg H, Caidahl K. Chromatographic and mass spectrometric methods for quantitative determination of 3-nitrotyrosine in biological samples and their application to human samples. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 851:160-71. [PMID: 17344105 DOI: 10.1016/j.jchromb.2007.02.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 01/29/2007] [Accepted: 02/01/2007] [Indexed: 11/24/2022]
Abstract
The permanent modification of soluble and protein-associated tyrosine by nitration results in the formation of 3-nitrotyrosine, which can be used as a marker of "nitro-oxidative" damage to proteins. Based on the analysis of patient materials, over 40 different diseases and/or conditions have been linked to increased nitration of tyrosine. They include many cardiovascular diseases, conditions associated with immunological reactions and neurological diseases. In this article we review the existing chromatographic and mass spectrometric methods for quantitative measurements of 3-nitrotyrosine in different human biological samples including plasma, either from the free amino acid pool or from hydrolyzed proteins from different matrices.
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Affiliation(s)
- Henrik Ryberg
- Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Göteborg, Göteborg, Sweden
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40
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Foster GE, Poulin MJ, Hanly PJ. Intermittent hypoxia and vascular function: implications for obstructive sleep apnoea. Exp Physiol 2006; 92:51-65. [PMID: 17124276 DOI: 10.1113/expphysiol.2006.035204] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Obstructive sleep apnoea (OSA) has been implicated as a risk factor for the development of hypertension, stroke and myocardial infarction. The main cause of cardiovascular and cerebrovascular disease in OSA is thought to be exposure to intermittent hypoxia, which can lead to oxidative stress, inflammation, atherosclerosis, endothelial dysfunction and hypertension. These proposed mechanisms have been drawn from basic research in animal and human models of intermittent hypoxia in addition to clinical investigation of patients with OSA. This review outlines the association between OSA and vascular disease, describes basic mechanisms that may be responsible for this association and compares the results from studies of OSA subjects with those in experimental models of intermittent hypoxia.
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Affiliation(s)
- Glen E Foster
- Department of Medicine, Faculty of Medicine, University of Calgary, Health Sciences Center, Room 1421, 3330 Hospital Drive NW, Calgary, Alberta, Canada
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Suzuki YJ, Jain V, Park AM, Day RM. Oxidative stress and oxidant signaling in obstructive sleep apnea and associated cardiovascular diseases. Free Radic Biol Med 2006; 40:1683-92. [PMID: 16678006 PMCID: PMC1995030 DOI: 10.1016/j.freeradbiomed.2006.01.008] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Revised: 12/09/2005] [Accepted: 01/11/2006] [Indexed: 12/21/2022]
Abstract
Obstructive sleep apnea (OSA) has emerged as a major public health problem and increasing evidence indicates that untreated OSA can lead to the development of various cardiovascular disorders. One important mechanism by which OSA may promote cardiovascular diseases is intermittent hypoxia, in which patients are subjected to repeated episodes of brief oxygen desaturation in the blood, followed by reoxygenation. Such cycles of hypoxia/reoxygenation may result in the generation of reactive oxygen species. Some studies have demonstrated the presence of oxidative stress in OSA patients as well as in animals subjected to intermittent hypoxia. Further, modulations of nitric oxide and biothiol status might also play important roles in the pathogenesis of OSA-associated diseases. Reactive oxygen species and redox events are also involved in the regulation of signal transduction for oxygen-sensing mechanisms. This review summarizes currently available information on the evidence for and against the occurrence of oxidative stress in OSA and the role of reactive oxygen species in cardiovascular changes associated with OSA.
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Affiliation(s)
- Yuichiro J Suzuki
- Department of Pharmacology, Georgetown University Medical Center, Room NW403, Medical-Dental Building, 3900 Reservoir Road NW, Washington, DC 20057, USA.
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Phillips SA, Olson EB, Lombard JH, Morgan BJ. Chronic intermittent hypoxia alters NE reactivity and mechanics of skeletal muscle resistance arteries. J Appl Physiol (1985) 2006; 100:1117-23. [PMID: 16357071 DOI: 10.1152/japplphysiol.00994.2005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Although arterial dilator reactivity is severely impaired during exposure of animals to chronic intermittent hypoxia (CIH), few studies have characterized vasoconstrictor responsiveness in resistance arteries of this model of sleep-disordered breathing. Sprague-Dawley rats were exposed to CIH (10% inspired O2 fraction for 1 min at 4-min intervals; 12 h/day) for 14 days. Control rats were housed under normoxic conditions. Diameters of isolated gracilis muscle resistance arteries (GA; 120–150 μm) were measured by television microscopy before and during exposure to norepinephrine (NE) and angiotensin II (ANG II) and at various intraluminal pressures between 20 and 140 mmHg in normal and Ca2+-free physiological salt solution. There was no difference in the ability of GA to constrict in response to ANG II ( P = 0.42; not significant; 10−10–10−7 M). However, resting tone, myogenic activation, and vasoconstrictor responses to NE ( P < 0.001; 10−9–10−6 M) were reduced in CIH vs. controls. Treatment of rats with the superoxide scavenger 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl (tempol; 1 mM) in the drinking water restored myogenic responses and NE-induced constrictions of CIH rats, suggesting that elevated superoxide production during exposure to CIH attenuates vasoconstrictor responsiveness to NE and myogenic activation in skeletal muscle resistance arteries. CIH also leads to an increased stiffness and reduced vessel wall distensibility that were not correctable with oral tempol treatment.
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Affiliation(s)
- Shane A Phillips
- Department of Physiology, Medical College of Wisconsin, Milwaukee, USA
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Baguet JP, Hammer L, Lévy P, Pierre H, Launois S, Mallion JM, Pépin JL. The severity of oxygen desaturation is predictive of carotid wall thickening and plaque occurrence. Chest 2005; 128:3407-12. [PMID: 16304292 DOI: 10.1378/chest.128.5.3407] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
STUDY OBJECTIVES To characterize carotid intima-media thickness (IMT) and plaque occurrence in patients with newly diagnosed obstructive sleep apnea (OSA) without known cardiovascular disease. DESIGN Prospective study. SETTING Sleep Laboratory and Department of Cardiology of Grenoble University Hospital. PATIENTS AND INTERVENTION OSA syndrome is associated with an increased cardiovascular risk. Carotid IMT is recognized as a marker of preclinic atheroma. A small number of studies have analyzed large-artery wall modifications in OSA syndrome. Eighty-three patients (74 men; mean age +/- SD, 48 +/- 11 years; mean body mass index, 27.4 +/- 4.2 kg/m(2)) were included. Mean respiratory disturbance index was 40.7 +/- 19.2/h, mean nocturnal arterial oxygen saturation (Sao(2)) was 93.1 +/- 2.0%, and mean percentage of recording time spent at Sao(2) < 90% was 8.6 +/- 16.8%. Clinical BP was measured following European Society of Hypertension/European Society of Cardiology recommendations, and 24-h ambulatory BP monitoring was assessed. Ultrasonography was used to determine the carotid IMT and atheromatous plaque occurrence. MEASUREMENTS AND RESULTS Twenty-five of 83 patients (30%) had carotid wall hypertrophy (IMT > 0.8 mm). In a logistic regression model, mean nocturnal Sao(2) < 92% (odds ratio [OR], 3.9; 95% confidence interval [CI], 1.1 to 12.7) was associated with carotid wall hypertrophy. ORs were even higher after adjustment for BP status (OR, 10.6; 95% CI, 1.6 to 50.9 in normotensive patients) and glucose levels (OR, 4.5; 95% CI, 1.0 to 20.9). Mean nocturnal Sao(2) < 92% and minimal nocturnal Sao(2) < 80% (ORs, 3.1 and 3.1; 95% CIs, 1.0 to 9.4 and 1.0 to 8.5, respectively) were associated with the presence of carotid plaque formation independently of the BP status (hypertensive or normotensive). CONCLUSIONS The severity of oxygen desaturation appears to be one of the best predictors for carotid IMT and plaque occurrence in OSA patients without known cardiovascular disease. Thus, carotid IMT and plaque formation appeared as early cardiovascular consequences in OSA patients.
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Affiliation(s)
- Jean-Philippe Baguet
- Department of Cardiology and Hypertension, University Hospital, EFCR University Hospital, Grenoble, France.
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Svatikova A, Wolk R, Lerman LO, Juncos LA, Greene EL, McConnell JP, Somers VK. Oxidative stress in obstructive sleep apnoea. Eur Heart J 2005; 26:2435-9. [PMID: 16105851 DOI: 10.1093/eurheartj/ehi440] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
AIMS Any sustained elevation of oxidative stress in patients with obstructive sleep apnoea (OSA) might help explain their increased risk for cardiovascular diseases. We tested the hypothesis that measures of oxidative stress are increased in otherwise healthy subjects with OSA when compared to closely matched OSA-free control subjects. METHODS AND RESULTS Plasma indices of oxidative stress and lipid peroxidation [thiobarbituric acid-reactive substances (TBARS), oxidized LDL (oxLDL), isoprostanes] were measured in 41 moderate-severe OSA males without other diseases and in 35 matched controls first before sleep, then after 4 h of untreated OSA, and again in the morning after 4 h of effective treatment with continuous positive airway pressure (CPAP). Plasma levels of oxLDL, TBARS, and isoprostanes in OSA patients (n=34, 26, 17, respectively) were comparable to the controls (n=28, 27, 15 for the three markers, respectively). Neither untreated OSA nor CPAP treatment nor normal sleep affected levels of any of the three measures of oxidative stress. There was no association between the severity of sleep apnoea and any measure of oxidative stress. CONCLUSION Otherwise healthy OSA patients, without any other co-morbidities, do not manifest evidence for higher oxidative stress and lipid peroxidation. Thus, oxidative stress and lipid peroxidation do not appear to be key mediators of increased cardiovascular disease in OSA patients.
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Affiliation(s)
- Anna Svatikova
- Mayo Clinic College of Medicine, Rochester, MN 55905, USA
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Tsikas D, Caidahl K. Recent methodological advances in the mass spectrometric analysis of free and protein-associated 3-nitrotyrosine in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 814:1-9. [PMID: 15607702 DOI: 10.1016/j.jchromb.2004.10.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2004] [Accepted: 10/04/2004] [Indexed: 10/26/2022]
Abstract
L-Tyrosine and L-tyrosine residues in proteins are attacked by various reactive-nitrogen species (RNS) including peroxynitrite to form 3-nitrotyrosine (NO(2)Tyr) and protein-associated 3-nitrotyrosine (NO(2)TyrProt). Circulating NO(2)Tyr and NO(2)TyrProt have been suggested and are widely used as biomarkers of oxidative stress in humans. In this article the mass spectrometry (MS)-based analytical methods recently reported for the quantification of circulating levels of NO(2)Tyr and NO(2)TyrProt are discussed. These methodologies differ in sensitivity, selectivity, specificity and accessibility to interferences with the latter mainly arising from artifactual formation of NO(2)Tyr and NO(2)TyrProt during sample treatment such as acidification and chemical derivatization. Application of these methodologies to healthy normal humans revealed basal circulating levels for NO(2)Tyr which range between 0.7 and 64 nM, i.e. by two orders of magnitude. Application of gas chromatography-tandem mass spectrometry (GC-tandem MS) methods by two independent research groups by using two different protocols to avoid artifactual nitration of L-tyrosine revealed almost identical mean plasma levels of the order of 1.0 nM in healthy humans. The lower limits of quantitation (LOQ) of these methods were 0.125 and 0.3n M, respectively. This order of magnitude for basal NO(2)Tyr is supported by two liquid chromatography-tandem mass spectrometry (LC-tandem MS) methods with LOQ values of 4.4 and 1.4 nM. On the basis of the data provided by GC-tandem MS and LC-tandem MS the use of a range of 0.5-3 nM for NO(2)Tyr and of 0.6 pmol/mg plasma protein or a molar ratio of 3-nitrotyrosine to tyrosine in plasma proteins of the order of 1:10(6) for NO(2)TyrProt in plasma of healthy humans as reference values appear reasonably justified. Recently reported clinical studies involving 3-nitrotyrosine as a biomarker of oxidative stress are discussed in particular from the analytical point of view.
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Affiliation(s)
- Dimitrios Tsikas
- Institute of Clinical Pharmacology, Hannover Medical School, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany.
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