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Olea E, Valverde-Pérez E, Docio I, Prieto-Lloret J, Aaronson PI, Rocher A. Pulmonary Vascular Responses to Chronic Intermittent Hypoxia in a Guinea Pig Model of Obstructive Sleep Apnea. Int J Mol Sci 2024; 25:7484. [PMID: 39000591 PMCID: PMC11242077 DOI: 10.3390/ijms25137484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 07/02/2024] [Accepted: 07/05/2024] [Indexed: 07/16/2024] Open
Abstract
Experimental evidence suggests that chronic intermittent hypoxia (CIH), a major hallmark of obstructive sleep apnea (OSA), boosts carotid body (CB) responsiveness, thereby causing increased sympathetic activity, arterial and pulmonary hypertension, and cardiovascular disease. An enhanced circulatory chemoreflex, oxidative stress, and NO signaling appear to play important roles in these responses to CIH in rodents. Since the guinea pig has a hypofunctional CB (i.e., it is a natural CB knockout), in this study we used it as a model to investigate the CB dependence of the effects of CIH on pulmonary vascular responses, including those mediated by NO, by comparing them with those previously described in the rat. We have analyzed pulmonary artery pressure (PAP), the hypoxic pulmonary vasoconstriction (HPV) response, endothelial function both in vivo and in vitro, and vascular remodeling (intima-media thickness, collagen fiber content, and vessel lumen area). We demonstrate that 30 days of the exposure of guinea pigs to CIH (FiO2, 5% for 40 s, 30 cycles/h) induces pulmonary artery remodeling but does not alter endothelial function or the contractile response to phenylephrine (PE) in these arteries. In contrast, CIH exposure increased the systemic arterial pressure and enhanced the contractile response to PE while decreasing endothelium-dependent vasorelaxation to carbachol in the aorta without causing its remodeling. We conclude that since all of these effects are independent of CB sensitization, there must be other oxygen sensors, beyond the CB, with the capacity to alter the autonomic control of the heart and vascular function and structure in CIH.
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Affiliation(s)
- Elena Olea
- Departamento de Enfermería, Facultad de Enfermería Universidad de Valladolid, 47005 Valladolid, Spain
- Unidad de Excelencia Instituto de Biomedicina y Genética Molecular (IBGM), Universidad de Valladolid-CSIC, 47005 Valladolid, Spain
| | - Esther Valverde-Pérez
- Unidad de Excelencia Instituto de Biomedicina y Genética Molecular (IBGM), Universidad de Valladolid-CSIC, 47005 Valladolid, Spain
- Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
| | - Inmaculada Docio
- Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
| | - Jesus Prieto-Lloret
- Unidad de Excelencia Instituto de Biomedicina y Genética Molecular (IBGM), Universidad de Valladolid-CSIC, 47005 Valladolid, Spain
- Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
| | - Philip I Aaronson
- Department of Inflammation Biology, School of Immunology and Microbial Sciences, Faculty of Life Sciences and Medicine, King's College London, London SE1 9RT, UK
| | - Asunción Rocher
- Unidad de Excelencia Instituto de Biomedicina y Genética Molecular (IBGM), Universidad de Valladolid-CSIC, 47005 Valladolid, Spain
- Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
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2
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Rajkov B, Zdravković M, Ninić A, Brajković M, Klašnja S, Gardijan V, Memon L, Munjas J, Mihajlović M, Spasojević-Kalimanovska V, Radosavljević V, Sopić M. Upregulation of peripheral blood mononuclear cells resistin gene expression in severe obstructive sleep apnea and obstructive sleep apnea with coexisting type 2 diabetes mellitus. Sleep Breath 2023; 27:2031-2039. [PMID: 36917442 DOI: 10.1007/s11325-023-02809-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/27/2023] [Accepted: 03/06/2023] [Indexed: 03/16/2023]
Abstract
PURPOSE Obstructive sleep apnea (OSA) is characterised by increased systemic inflammation, and is often accompanied with type 2 diabetes mellitus (T2DM) and cardiovascular disease. The aim of this investigation was to evaluate gene expression of resistin, its receptor CAP1 and CD36 as the indicators of the inflammatory changes in PBMCs in relation to the severity of OSA, and the presence of type 2 diabetes mellitus (T2DM) in OSA. METHODS Severity of OSA was defined by the apnea/hypopnea index (AHI): AHI < 30: mild to moderate OSA (MM-OSA), AHI ≥ 30: severe OSA (S-OSA). Presence of T2DM was captured: OSA with T2DM (OSA + T2DM), OSA without T2DM (OSA-T2DM). PBMC resistin, CAP1, and CD36 mRNA were determined by real-time PCR. RESULTS Resistin mRNA was significantly upregulated in S-OSA (N = 54) compared to the MM-OSA (N = 52, P = 0.043); CAP1 and CD36 mRNA levels did not differ between the groups (P = 0.302; P = 0.166, respectively). Resistin mRNA was significantly upregulated in OSA + T2DM (N = 29) compared to the OSA-T2DM (N = 77, P = 0.029); CAP1 and CD36 mRNA levels did not differ between the groups (P = 0.662; P = 0.108, respectively). AHI and T2DM were independent predictors of resistin mRNA above the 75th percentile (OR = 3.717 [1.152-11.991]; OR = 3.261 [1.000-10.630], P = 0.042 respectively). CONCLUSION Resistin gene upregulation in S-OSA indicates its possible contribution to increased inflammation in S-OSA and makes it a possible marker of the disease severity. Resistin gene upregulation in OSA + T2DM suggests that a joint effect of these two comorbidities may have a major contribution to increased inflammation and complications that arise from this state.
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Affiliation(s)
- Branislava Rajkov
- Department of Medical Biochemistry, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia
| | - Marija Zdravković
- Department of Cardiology, University Medical Center "Bežanijska Kosa", Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ana Ninić
- Department of Medical Biochemistry, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia.
| | - Milica Brajković
- Department of Pulmology, University Medical Center "Bežanijska Kosa", Belgrade, Serbia
| | - Slobodan Klašnja
- Department of Cardiology, University Medical Center "Bežanijska Kosa", Belgrade, Serbia
| | - Vera Gardijan
- Department of Pulmology, University Medical Center "Bežanijska Kosa", Belgrade, Serbia
| | - Lidija Memon
- Department of Laboratory Diagnostics, University Medical Center "Bežanijska Kosa", Belgrade, Serbia
| | - Jelena Munjas
- Department of Medical Biochemistry, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia.
| | - Marija Mihajlović
- Department of Medical Biochemistry, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia
| | | | | | - Miron Sopić
- Department of Medical Biochemistry, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia.
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3
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Alterki A, Abu-Farha M, Al Shawaf E, Al-Mulla F, Abubaker J. Investigating the Relationship between Obstructive Sleep Apnoea, Inflammation and Cardio-Metabolic Diseases. Int J Mol Sci 2023; 24:ijms24076807. [PMID: 37047780 PMCID: PMC10095553 DOI: 10.3390/ijms24076807] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/28/2023] [Accepted: 03/30/2023] [Indexed: 04/14/2023] Open
Abstract
Obstructive sleep apnoea (OSA) is a prevalent underdiagnosed disorder whose incidence increases with age and weight. Uniquely characterised by frequent breathing interruptions during sleep-known as intermittent hypoxia (IH)-OSA disrupts the circadian rhythm. Patients with OSA have repeated episodes of hypoxia and reoxygenation, leading to systemic consequences. OSA consequences range from apparent symptoms like excessive daytime sleepiness, neurocognitive deterioration and decreased quality of life to pathological complications characterised by elevated biomarkers linked to endocrine-metabolic and cardiovascular changes. OSA is a well-recognized risk factor for cardiovascular and cerebrovascular diseases. Furthermore, OSA is linked to other conditions that worsen cardiovascular outcomes, such as obesity. The relationship between OSA and obesity is complex and reciprocal, involving interaction between biological and lifestyle factors. The pathogenesis of both OSA and obesity involve oxidative stress, inflammation and metabolic dysregulation. The current medical practice uses continuous positive airway pressure (CPAP) as the gold standard tool to manage OSA. It has been shown to improve symptoms and cardiac function, reduce cardiovascular risk and normalise biomarkers. Nonetheless, a full understanding of the factors involved in the deleterious effects of OSA and the best methods to eliminate their occurrence are still poorly understood. In this review, we present the factors and evidence linking OSA to increased risk of cardiovascular conditions.
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Affiliation(s)
- Abdulmohsen Alterki
- Department of Otolaryngology Head & Neck Surgery, Zain and Al Sabah Hospitals and Dasman Diabetes Institute, Dasman 15462, Kuwait
| | - Mohamed Abu-Farha
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute, Dasman 15462, Kuwait
| | - Eman Al Shawaf
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute, Dasman 15462, Kuwait
| | - Fahd Al-Mulla
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute, Dasman 15462, Kuwait
| | - Jehad Abubaker
- Department of Biochemistry and Molecular Biology, Dasman Diabetes Institute, Dasman 15462, Kuwait
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4
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Cortese R, Adams TS, Cataldo KH, Hummel J, Kaminski N, Kheirandish-Gozal L, Gozal D. Single-cell RNA-seq uncovers cellular heterogeneity and provides a signature for paediatric sleep apnoea. Eur Respir J 2023; 61:13993003.01465-2022. [PMID: 36356973 DOI: 10.1183/13993003.01465-2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/22/2022] [Indexed: 11/12/2022]
Abstract
BACKGROUND Obstructive sleep apnoea (OSA) is a highly prevalent disease and a major cause of systemic inflammation leading to neurocognitive, behavioural, metabolic and cardiovascular dysfunction in children and adults. However, the impact of OSA on the heterogeneity of circulating immune cells remains to be determined. METHODS We applied single-cell transcriptomics analysis (scRNA-seq) to identify OSA-induced changes in transcriptional landscape in peripheral blood mononuclear cell (PBMC) composition, which uncovered severity-dependent differences in several cell lineages. Furthermore, a machine-learning approach was used to combine scRNAs-seq cell-specific markers with those differentially expressed in OSA. RESULTS scRNA-seq demonstrated OSA-induced heterogeneity in cellular composition and enabled the identification of previously undescribed cell types in PBMCs. We identified a molecular signature consisting of 32 genes, which distinguished OSA patients from various controls with high precision (area under the curve 0.96) and accuracy (93% positive predictive value and 95% negative predictive value) in an independent PBMC bulk RNA expression dataset. CONCLUSION OSA deregulates systemic immune function and displays a molecular signature that can be assessed in standard cellular RNA without the need for pre-analytical cell separation, thereby making the assay amenable to application in a molecular diagnostic setting.
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Affiliation(s)
- Rene Cortese
- Department of Child Health, Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Taylor S Adams
- Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Kylie H Cataldo
- Department of Child Health, Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Justin Hummel
- Institute for Data Science and Informatics, University of Missouri, Columbia, MO, USA
| | - Naftali Kaminski
- Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, CT, USA
| | - Leila Kheirandish-Gozal
- Department of Child Health, Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - David Gozal
- Department of Child Health, Child Health Research Institute, School of Medicine, University of Missouri, Columbia, MO, USA
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5
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Dahan T, Nassar S, Yajuk O, Steinberg E, Benny O, Abudi N, Plaschkes I, Benyamini H, Gozal D, Abramovitch R, Gileles-Hillel A. Chronic Intermittent Hypoxia during Sleep Causes Browning of Interscapular Adipose Tissue Accompanied by Local Insulin Resistance in Mice. Int J Mol Sci 2022; 23:ijms232415462. [PMID: 36555109 PMCID: PMC9779339 DOI: 10.3390/ijms232415462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/01/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Obstructive sleep apnea (OSA) is a highly prevalent condition, characterized by intermittent hypoxia (IH), sleep disruption, and altered autonomic nervous system function. OSA has been independently associated with dyslipidemia, insulin resistance, and metabolic syndrome. Brown adipose tissue (BAT) has been suggested as a modulator of systemic glucose tolerance through adaptive thermogenesis. Reductions in BAT mass have been associated with obesity and metabolic syndrome. No studies have systematically characterized the effects of chronic IH on BAT. Thus, we aimed to delineate IH effects on BAT and concomitant metabolic changes. C57BL/6J 8-week-old male mice were randomly assigned to IH during sleep (alternating 90 s cycles of 6.5% FIO2 followed by 21% FIO2) or normoxia (room air, RA) for 10 weeks. Mice were subjected to glucose tolerance testing and 18F-FDG PET-MRI towards the end of the exposures followed by BAT tissues analyses for morphological and global transcriptomic changes. Animals exposed to IH were glucose intolerant despite lower total body weight and adiposity. BAT tissues in IH-exposed mice demonstrated characteristic changes associated with "browning"-smaller lipids, increased vascularity, and a trend towards higher protein levels of UCP1. Conversely, mitochondrial DNA content and protein levels of respiratory chain complex III were reduced. Pro-inflammatory macrophages were more abundant in IH-exposed BAT. Transcriptomic analysis revealed increases in fatty acid oxidation and oxidative stress pathways in IH-exposed BAT, along with a reduction in pathways related to myogenesis, hypoxia, and IL-4 anti-inflammatory response. Functionally, IH-exposed BAT demonstrated reduced absorption of glucose on PET scans and reduced phosphorylation of AKT in response to insulin. Current studies provide initial evidence for the presence of a maladaptive response of interscapular BAT in response to chronic IH mimicking OSA, resulting in a paradoxical divergence, namely, BAT browning but tissue-specific and systemic insulin resistance. We postulate that oxidative stress, mitochondrial dysfunction, and inflammation may underlie these dichotomous outcomes in BAT.
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Affiliation(s)
- Tehila Dahan
- The Wohl Institute for Translational Medicine, Hadassah Medical Center, Jerusalem 91120, Israel
| | - Shahd Nassar
- The Wohl Institute for Translational Medicine, Hadassah Medical Center, Jerusalem 91120, Israel
- Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Olga Yajuk
- Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Eliana Steinberg
- The Institute for Drug Research, The School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ofra Benny
- The Institute for Drug Research, The School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Nathalie Abudi
- The Wohl Institute for Translational Medicine, Hadassah Medical Center, Jerusalem 91120, Israel
| | - Inbar Plaschkes
- Info-CORE, Bioinformatics Unit of the I-CORE, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Hadar Benyamini
- Info-CORE, Bioinformatics Unit of the I-CORE, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - David Gozal
- Division of Pediatric Pulmonology, Allergy and Immunology, Comprehensive Sleep Medicine Center, Department of Child Health and Child Health Research Institute, MU Children’s Hospital, University of Missouri School of Medicine, Columbia, MO 65201, USA
| | - Rinat Abramovitch
- The Wohl Institute for Translational Medicine, Hadassah Medical Center, Jerusalem 91120, Israel
- Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Alex Gileles-Hillel
- The Wohl Institute for Translational Medicine, Hadassah Medical Center, Jerusalem 91120, Israel
- Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Pediatric Pulmonology and Sleep Unit, Department of Pediatrics, Hadassah Medical Center, Jerusalem 91120, Israel
- Correspondence:
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6
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Barnes LA, Mesarwi OA, Sanchez-Azofra A. The Cardiovascular and Metabolic Effects of Chronic Hypoxia in Animal Models: A Mini-Review. Front Physiol 2022; 13:873522. [PMID: 35432002 PMCID: PMC9008331 DOI: 10.3389/fphys.2022.873522] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 03/11/2022] [Indexed: 11/13/2022] Open
Abstract
Animal models are useful to understand the myriad physiological effects of hypoxia. Such models attempt to recapitulate the hypoxemia of human disease in various ways. In this mini-review, we consider the various animal models which have been deployed to understand the effects of chronic hypoxia on pulmonary and systemic blood pressure, glucose and lipid metabolism, atherosclerosis, and stroke. Chronic sustained hypoxia (CSH)-a model of chronic lung or heart diseases in which hypoxemia may be longstanding and persistent, or of high altitude, in which effective atmospheric oxygen concentration is low-reliably induces pulmonary hypertension in rodents, and appears to have protective effects on glucose metabolism. Chronic intermittent hypoxia (CIH) has long been used as a model of obstructive sleep apnea (OSA), in which recurrent airway occlusion results in intermittent reductions in oxyhemoglobin saturations throughout the night. CIH was first shown to increase systemic blood pressure, but has also been associated with other maladaptive physiological changes, including glucose dysregulation, atherosclerosis, progression of nonalcoholic fatty liver disease, and endothelial dysfunction. However, models of CIH have generally been implemented so as to mimic severe human OSA, with comparatively less focus on milder hypoxic regimens. Here we discuss CSH and CIH conceptually, the effects of these stimuli, and limitations of the available data.
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Affiliation(s)
- Laura A. Barnes
- Division of Pulmonary, Critical Care, and Sleep Medicine and Physiology, Department of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Omar A. Mesarwi
- Division of Pulmonary, Critical Care, and Sleep Medicine and Physiology, Department of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Ana Sanchez-Azofra
- Division of Pulmonary, Critical Care, and Sleep Medicine and Physiology, Department of Medicine, University of California, San Diego, San Diego, CA, United States
- Servicio de Neumología, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Madrid, Spain
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7
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Delsart P, Soquet J, Pierache A, Dedeken M, Fry S, Mallart A, Pontana F, Azzaoui R, Juthier F, Sobocinski J, Mounier-Vehier C. Influence of nocturnal hypoxemia on follow-up course after type B acute aortic syndrome. BMC Pulm Med 2021; 21:401. [PMID: 34872556 PMCID: PMC8647351 DOI: 10.1186/s12890-021-01778-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 11/19/2021] [Indexed: 12/02/2022] Open
Abstract
Introduction Association between sleep nocturnal breathing disorders and acute aortic syndrome (AAS) has been described but mid-term data are scarce. Objectives We assessed the prognostic value of sleep apnea parameters and their relationship with aortic morphology after the onset of a type B AAS. Methods Between January 2010 and January 2018, sleep apnea screening in post type B AAS was prospectively performed. The association of sleep apnea parameters with aortic morphology and aortic expansion during follow-up was studied. Results Over the 8-year-study period, 103 patients were included, with a mean age of 57.8 ± 12.1 years old. Median follow-up was 25.0 months (11.0–51.0). Thirty-two patients (31%) required aortic stenting during the acute phase. In patients treated by aortic stenting, the descending thoracic aortic diameter was positively associated with a higher percentage of nocturnal time of saturation ≤ 90% after adjustment (p = 0.016). During follow-up, the nocturnal time of saturation ≤ 90% in patients treated by medical therapy was the only parameter associated with significant aortic expansion rate (r = 0.26, p = 0.04). Thirty-eight patients started and sustained nocturnal ventilation during follow-up. The association between aortic expansion rate and nocturnal time of saturation ≤ 90% did not persist during follow-up after adjustment on nocturnal ventilation initiation (r = 0.25, p = 0.056). Conclusions Nocturnal hypoxemia parameters are positively associated with the max onset aortic diameter and significant aortic growth after type B AAS. Nocturnal ventilation seems to mitigate aortic expansion during follow-up. Supplementary Information The online version contains supplementary material available at 10.1186/s12890-021-01778-y.
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Affiliation(s)
- Pascal Delsart
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France. .,Vascular Medicine and Hypertension Department, Institut-Coeur-Poumon, Boulevard Pr Leclercq, 59037, Lille Cedex, France.
| | - Jerome Soquet
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France.,University of Lille, CHU Lille, 59000, Lille, France
| | - Adeline Pierache
- Service d'épidémiologie et de santé publique, University of Lille, CHU Lille, 59000, Lille, France
| | - Maxime Dedeken
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France
| | - Stephanie Fry
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France
| | - Anne Mallart
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France
| | - François Pontana
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France.,University of Lille, CHU Lille, 59000, Lille, France
| | - Richard Azzaoui
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France
| | - Francis Juthier
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France.,University of Lille, CHU Lille, 59000, Lille, France
| | - Jonathan Sobocinski
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France.,University of Lille, CHU Lille, 59000, Lille, France
| | - Claire Mounier-Vehier
- Lille, Institut Cœur Poumon, Bd Pr Leclercq, 59000, Lille, France.,University of Lille, CHU Lille, 59000, Lille, France.,Vascular Medicine and Hypertension Department, Institut-Coeur-Poumon, Boulevard Pr Leclercq, 59037, Lille Cedex, France
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8
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Li L, Yang Y, Zhang H, Du Y, Jiao X, Yu H, Wang Y, Lv Q, Li F, Sun Q, Qin Y. Salidroside Ameliorated Intermittent Hypoxia-Aggravated Endothelial Barrier Disruption and Atherosclerosis via the cAMP/PKA/RhoA Signaling Pathway. Front Pharmacol 2021; 12:723922. [PMID: 34504429 PMCID: PMC8421548 DOI: 10.3389/fphar.2021.723922] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/11/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Endothelial barrier dysfunction plays a key role in atherosclerosis progression. The primary pathology of obstructive sleep apnea-hypopnea syndrome is chronic intermittent hypoxia (IH), which induces reactive oxygen species (ROS) overproduction, endothelial barrier injury, and atherosclerosis. Salidroside, a typical pharmacological constituent of Rhodiola genus, has documented antioxidative, and cardiovascular protective effects. However, whether salidroside can improve IH-aggravated endothelial barrier dysfunction and atherosclerosis has not been elucidated. Methods and results: In normal chow diet-fed ApoE−/− mice, salidroside (100 mg/kg/d, p. o.) significantly ameliorated the formation of atherosclerotic lesions and barrier injury aggravated by 7-weeks IH (21%–5%–21%, 120 s/cycle). In human umbilical vein endothelial cells (HUVECs), exposure to IH (21%–5%–21%, 40 min/cycle, 72 cycles) decreased transendothelial electrical resistance and protein expression of vascular endothelial cadherin (VE-cadherin) and zonula occludens 1. In addition, IH promoted ROS production and activated ras homolog gene family member A (RhoA)/Rho-associated protein kinase (ROCK) pathway. All of these effects of IH were reversed by salidroside. Similar to salidroside, ROCK-selective inhibitors Y26732, and Fasudil protected HUVECs from IH-induced ROS overproduction and endothelial barrier disruption. Furthermore, salidroside increased intracellular cAMP levels, while the PKA-selective inhibitor H-89 attenuated the effects of salidroside on IH-induced RhoA/ROCK suppression, ROS scavenging, and barrier protection. Conclusion: Our findings demonstrate that salidroside effectively ameliorated IH-aggravated endothelial barrier injury and atherosclerosis, largely through the cAMP/PKA/RhoA signaling pathway.
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Affiliation(s)
- Linyi Li
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Yunyun Yang
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Huina Zhang
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Yunhui Du
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Xiaolu Jiao
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Huahui Yu
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Yu Wang
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Qianwen Lv
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Fan Li
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Qiuju Sun
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
| | - Yanwen Qin
- The Key Laboratory of Upper Airway Dysfunction-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Capital Medical University, Beijing, China.,The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing Anzhen Hospital, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Institute of Heart, Lung and Blood Vessel Disease, Beijing, China
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9
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Agaltsov MV, Drapkina OM. Obstructive sleep apnea and cardiovascular comorbidity: common pathophysiological mechanisms to cardiovascular disease. RATIONAL PHARMACOTHERAPY IN CARDIOLOGY 2021. [DOI: 10.20996/1819-6446-2021-08-05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Obstructive sleep apnea (OSA) is associated with many cardiovascular and metabolic diseases. Sleep apnea causes intermittent hypoxemia, chest pressure fluctuations and a reaction from the cerebral cortex in the form of a short awakening during sleep (EEG-activation). The consequences of pathological pathways are studied in experimental models involving cell cultures, animals, and healthy volunteers. At present, the negative impact of intermittent hypoxemia on a variety of pathophysiological disorders of the heart and blood vessels (vascular tone fluctuations, thickening of the intimamedia complex in the vascular wall, direct damaging effect on the myocardium) has a great evidence base. Two other pathological components of OSA (pressure fluctuations and EEG-activation) can also affect cardiovascular system, mainly affecting the increase in blood pressure and changing cardiac hemodynamics. Although these reactions are considered separately in the review, with the development of sleep apnea they occur sequentially and are closely interrelated. As a result, these pathological pathways trigger further pathophysiological mechanisms acting on the heart and blood vessels. It is known that these include excessive sympathetic activation, inflammation, oxidative stress and metabolic dysregulation. In many respects being links of one process, these mechanisms can trigger damage to the vascular wall, contributing to the formation of atherosclerotic lesions. The accumulated data with varying degrees of reliability confirm the participation of OSA through these processes in the formation of cardiovascular disorders. There are factors limiting direct evidence of this interaction (sleep deprivation, causing similar changes, as well as the inability to share the contribution of other risk factors for cardiovascular diseases, in particular arterial hypertension, obesity, which are often associated with OSA). It is necessary to continue the study of processes that implement the pathological effect of OSA on the cardiovascular system.
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Affiliation(s)
- M. V. Agaltsov
- National Medical Research Center for Therapy and Preventive Medicine
| | - O. M. Drapkina
- National Medical Research Center for Therapy and Preventive Medicine
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10
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Sanz-Rubio D, Khalyfa A, Qiao Z, Ullate J, Marin JM, Kheirandish-Gozal L, Gozal D. Cell-Selective Altered Cargo Properties of Extracellular Vesicles Following In Vitro Exposures to Intermittent Hypoxia. Int J Mol Sci 2021; 22:ijms22115604. [PMID: 34070558 PMCID: PMC8198838 DOI: 10.3390/ijms22115604] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 05/09/2021] [Accepted: 05/19/2021] [Indexed: 01/09/2023] Open
Abstract
Intermittent hypoxia (IH), a hallmark of obstructive sleep apnea (OSA), is associated with cardiovascular and metabolic dysfunction. However, the mechanisms underlying these morbidities remain poorly delineated. Extracellular vesicles (EVs) mediate intercellular communications, play pivotal roles in a multitude of physiological and pathological processes, and could mediate IH-induced cellular effects. Here, the effects of IH on human primary cells and the release of EVs were examined. Microvascular endothelial cells (HMVEC-d), THP1 monocytes, THP1 macrophages M0, THP1 macrophages M1, THP1 macrophages M2, pre-adipocytes, and differentiated adipocytes (HAd) were exposed to either room air (RA) or IH for 24 h. Secreted EVs were isolated and characterized using transmission electron microscopy, nanoparticle tracking analysis, and Western blotting. The effects of each of the cell-derived EVs on endothelial cell (EC) monolayer barrier integrity, on naïve THP1 macrophage polarity, and on adipocyte insulin sensitivity were also evaluated. IH did not alter EVs cell quantal release, but IH-EVs derived from HMVEC-d (p < 0.01), THP1 M0 (p < 0.01) and HAd (p < 0.05) significantly disrupted HMVEC-d monolayer integrity, particularly after H2O2 pre-conditioning. IH-EVs from HMVEC-d and THP1 M0 elicited M2-polarity changes did not alter insulin sensitivity responses. IH induces cell-selective changes in EVs cargo, which primarily seem to target the emergence of endothelial dysfunction. Thus, changes in EVs cargo from selected cell sources in vivo may play causal roles in some of the adverse outcomes associated with OSA.
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Affiliation(s)
- David Sanz-Rubio
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
- Translational Research Unit, Hospital Universitario Miguel Servet, Instituto de Investigación Sanitaria de Aragón (IISAragón), 50009 Zaragoza, Spain;
| | - Abdelnaby Khalyfa
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
- Correspondence: ; Tel.: +1-573-884-7685
| | - Zhuanhong Qiao
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
| | - Jorge Ullate
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
| | - José M. Marin
- Translational Research Unit, Hospital Universitario Miguel Servet, Instituto de Investigación Sanitaria de Aragón (IISAragón), 50009 Zaragoza, Spain;
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERes), 28029 Madrid, Spain
| | - Leila Kheirandish-Gozal
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
| | - David Gozal
- Department of Child Health, Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65201, USA; (D.S.-R.); (Z.Q.); (J.U.); (L.K.-G.); (D.G.)
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11
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Mochol J, Gawrys J, Gajecki D, Szahidewicz-Krupska E, Martynowicz H, Doroszko A. Cardiovascular Disorders Triggered by Obstructive Sleep Apnea-A Focus on Endothelium and Blood Components. Int J Mol Sci 2021; 22:5139. [PMID: 34066288 PMCID: PMC8152030 DOI: 10.3390/ijms22105139] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/09/2021] [Accepted: 05/10/2021] [Indexed: 12/19/2022] Open
Abstract
Obstructive sleep apnea (OSA) is known to be an independent cardiovascular risk factor. Among arousal from sleep, increased thoracic pressure and enhanced sympathetic activation, intermittent hypoxia is now considered as one of the most important pathophysiological mechanisms contributing to the development of endothelial dysfunction. Nevertheless, not much is known about blood components, which justifies the current review. This review focuses on molecular mechanisms triggered by sleep apnea. The recurrent periods of hypoxemia followed by reoxygenation promote reactive oxygen species (ROS) overproduction and increase inflammatory response. In this review paper we also intend to summarize the effect of treatment with continuous positive airway pressure (CPAP) on changes in the profile of the endothelial function and its subsequent potential clinical advantage in lowering cardiovascular risk in other comorbidities such as diabetes, atherosclerosis, hypertension, atrial fibrillation. Moreover, this paper is aimed at explaining how the presence of OSA may affect platelet function and exert effects on rheological activity of erythrocytes, which could also be the key to explaining an increased risk of stroke.
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Affiliation(s)
| | | | | | | | | | - Adrian Doroszko
- Department of Internal Medicine, Hypertension and Clinical Oncology, Faculty of Medicine, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland; (J.M.); (J.G.); (D.G.); (E.S.-K.); (H.M.)
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12
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Castellana R, Aringhieri G, Gargani L, Maestri M, Schirru A, Bonanni E, Faraguna U. Effects of obstructive sleep apnea on the thoracic aorta and the main pulmonary artery: assessment by CT. J Clin Sleep Med 2021; 17:3-11. [PMID: 32876043 DOI: 10.5664/jcsm.8770] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
STUDY OBJECTIVES The influence of obstructive sleep apnea (OSA) on thoracic aortic size is debated. We aimed to identify possible relations between sleep parameters and the sizes of the ascending aorta (AA), the descending thoracic aorta (DTA), and the main pulmonary artery (MPA) in patients with untreated OSA and in a subgroup of participants without comorbidities capable of affecting the size of great thoracic vessels. METHODS We retrospectively measured AA, DTA, and MPA sizes on the chest computed tomography scans of 60 patients with OSA who underwent sleep studies within 1 year before or after the computed tomography. Univariate and multivariate analyses were performed on all patient findings, while an additional univariate analysis was conducted on the data for 22 participants without comorbidities. The latter had been divided into subgroups depending on the sleep parameters, and comparisons were made between them. RESULTS The logarithm of the time of oxygen saturation below 90% (CT90) significantly predicted AA and MPA sizes in all patients with OSA (P < .05). Oxygen desaturation index and minimum oxygen saturation were moderately correlated with AA and DTA sizes in patients without comorbidities (P < .01). In this group, subjects with oxygen desaturation index > 30 or minimum oxygen saturation < 81% had greater AA and DTA dimensions (P < .05). CONCLUSIONS In patients with OSA, time of oxygen saturation < 90% influenced AA and MPA sizes. In those patients without comorbidities, oxygen desaturation index and minimum oxygen saturation were moderately correlated with both AA and DTA sizes. Participants without comorbidities with oxygen desaturation index > 30 or minimum oxygen saturation < 81% had greater AA and DTA dimensions.
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Affiliation(s)
- Roberto Castellana
- Diagnostic and Interventional Radiology, University of Pisa, Pisa, Italy
| | - Giacomo Aringhieri
- Diagnostic and Interventional Radiology, University of Pisa, Pisa, Italy
| | - Luna Gargani
- Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Michelangelo Maestri
- Department of Clinical and Experimental Medicine, Neurology Unit, University of Pisa, Pisa, Italy
| | - Alessandro Schirru
- Department of Clinical and Experimental Medicine, Neurology Unit, University of Pisa, Pisa, Italy
| | - Enrica Bonanni
- Department of Clinical and Experimental Medicine, Neurology Unit, University of Pisa, Pisa, Italy
| | - Ugo Faraguna
- Department of Translational Research and of New Surgical and Medical Technologies, University of Pisa, Pisa, Italy.,Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, Pisa, Italy
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13
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Fitzpatrick SF, King AD, O'Donnell C, Roche HM, Ryan S. Mechanisms of intermittent hypoxia-mediated macrophage activation - potential therapeutic targets for obstructive sleep apnoea. J Sleep Res 2020; 30:e13202. [PMID: 32996666 DOI: 10.1111/jsr.13202] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/31/2020] [Accepted: 09/06/2020] [Indexed: 01/24/2023]
Abstract
Intermittent hypoxia (IH) plays a key role in the pathogenesis of insulin resistance (IR) in obstructive sleep apnoea (OSA). IH induces a pro-inflammatory phenotype of the adipose tissue with M1 macrophage polarisation, subsequently impeding adipocyte insulin signalling, and these changes are in striking similarity to those seen in obesity. However, the detailed molecular mechanisms of IH-induced macrophage polarisation are unknown and identification of same should lead to the identification of novel therapeutic targets. In the present study, we tested the hypothesis that IH acts through similar mechanisms as obesity, activating Toll-like-receptor (TLR)4/nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) signalling pathways leading to the upregulation and secretion of the key cytokines interleukin (IL)-1β and IL-6. Bone-marrow derived macrophages (BMDMs) from lean and obese C57BL/6 male mice were exposed to a state-of-the-art in vitro model of IH. Independent of obesity, IH led to a pro-inflammatory M1 phenotype characterised by increased inducible nitric oxide synthase and IL-6 mRNA expression, robust increase in NF-κB DNA-binding activity and IL-6 secretion. Furthermore, IH significantly increased pro-IL-1β mRNA and protein expression and mature IL-1β secretion compared to control treatment. Providing mechanistic insight, pre-treatment with the TLR4 specific inhibitor, TAK-242, prevented IH-induced M1 polarisation and upregulation of IL-1β mRNA and pro-IL-1β protein expression. Moreover, IH-induced increase in IL-1β secretion was prevented in BMDMs isolated from NLRP3 knockout mice. Thus, targeting TLR4/NF-κB and NLRP3 signalling pathways may provide novel therapeutic options for metabolic complications in OSA.
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Affiliation(s)
- Susan F Fitzpatrick
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland
| | - Ailbhe D King
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland
| | - Cliona O'Donnell
- Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland
| | - Helen M Roche
- Nutrigenomics Research Group, School of Public Health, Physiotherapy and Sports Science, UCD Institute of Food and Health, Diabetes Complications Research Centre, University College Dublin, Dublin, Ireland.,Institute for Global Food Security, Queen's University Belfast, Belfast, UK
| | - Silke Ryan
- School of Medicine, Conway Institute, University College Dublin, Dublin, Ireland.,Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland
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14
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Aortic remodelling induced by obstructive apneas is normalized with mesenchymal stem cells infusion. Sci Rep 2019; 9:11443. [PMID: 31391506 PMCID: PMC6685984 DOI: 10.1038/s41598-019-47813-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 07/22/2019] [Indexed: 02/08/2023] Open
Abstract
Obstructive sleep apnea syndrome (OSA) promotes aortic dilatation, increased stiffness and accelerated atherosclerosis, but the mechanisms of vascular remodelling are not known. We aimed to assess vascular remodelling, its mechanisms, and the effect of mesenchymal stem cells (MSC) infusions in a clinically relevant rat model of chronic OSA involving recurrent airway obstructions leading thoracic pressure swings and intermittent hypoxia/hypercapnia (OSA-rats). Another group of rats were placed in the same setup without air obstructions (Sham-rats) and were considered controls. Our study demonstrates that chronic, non-invasive repetitive airway obstructions mimicking OSA promote remarkable structural changes of the descending thoracic aorta such as eccentric aortic hypertrophy due to an increased wall thickness and lumen diameter, an increase in the number of elastin fibers which, in contrast, get ruptured, but no changes in tunica media fibrosis. As putative molecular mechanisms of the OSA-induced vascular changes we identified an increase in reactive oxygen species and renin-angiotensin system markers and an imbalance in oxide nitric synthesis. Our results also indicate that MSC infusion blunts the OSA-related vascular changes, most probably due to their anti-inflammatory properties.
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15
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Prolyl 4-Hydroxylase Domain Protein 3-Inhibited Smooth-Muscle-Cell Dedifferentiation Improves Cardiac Perivascular Fibrosis Induced by Obstructive Sleep Apnea. BIOMED RESEARCH INTERNATIONAL 2019; 2019:9174218. [PMID: 31346526 PMCID: PMC6621170 DOI: 10.1155/2019/9174218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 04/10/2019] [Accepted: 06/02/2019] [Indexed: 12/13/2022]
Abstract
Background Intermittent hypoxia (IH) induced by obstructive sleep apnea (OSA) is a leading factor affecting cardiovascular fibrosis. Under IH condition, smooth muscle cells (SMAs) respond by dedifferentiation, which is associated with vascular remodelling. The expression of prolyl 4-hydroxylase domain protein 3 (PHD3) increases under hypoxia. However, the role of PHD3 in OSA-induced SMA dedifferentiation and cardiovascular fibrosis remains uncertain. Methods We explored the mechanism of cardiovascular remodelling in C57BL/6 mice exposed to IH for 3 months and investigated the mechanism of PHD3 in improving the remodelling in vivo and vitro. Results In vivo remodelling showed that IH induced cardiovascular fibrosis via SMC dedifferentiation and that fibrosis improved when PHD3 was overexpressed. In vitro remodelling showed that IH induced SMA dedifferentiation, which secretes much collagen I. PHD3 overexpression in cultured SMCs reversed the dedifferentiation by degrading and inactivating HIF-1α. Conclusion OSA-induced cardiovascular fibrosis was associated with SMC dedifferentiation, and PHD3 overexpression may benefit its prevention by reversing the dedifferentiation. Therefore, PHD3 overexpression has therapeutic potential in disease treatment.
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16
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Castro-Grattoni AL, Suarez-Giron M, Benitez I, Torres M, Almendros I, Farre R, Montserrat JM, Dalmases M, Gozal D, Sánchez-de-la-Torre M. Effect of age on the cardiovascular remodelling induced by chronic intermittent hypoxia as a murine model of sleep apnoea. Respirology 2019; 25:312-320. [PMID: 31215129 DOI: 10.1111/resp.13610] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 03/08/2019] [Accepted: 05/01/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND OBJECTIVE Chronic intermittent hypoxia (CIH) is a major determinant of the cardiovascular morbidity associated with obstructive sleep apnoea (OSA), and the magnitude of CIH impact may be influenced by ageing. Here, we assessed the role of ageing in the early cardiovascular structural remodelling induced by severe CIH in a murine model of OSA. METHODS Cardiovascular remodelling was assessed in young (2 months old, n = 20) and aged (18 months old, n = 20) C57BL/6 female mice exposed to CIH (20% O2 for 40 s, 5% O2 for 20 s) or normoxia (room air) for 8 weeks (6 h/day). RESULTS Early vascular remodelling was observed in young mice exposed to CIH as illustrated by intima-media thickening (mean change: 4.6 ± 2.6 μm; P = 0.02), elastin fibre disorganization (mean change: 9.2 ± 4.5%; P = 0.02) and fragmentation (mean change: 2.5 ± 0.8%; P = 0.03), and collagen (mean change: 3.2 ± 0.6%; P = 0.001) and mucopolysaccharide accumulation (mean change: 2.4 ± 0.8%; P = 0.01). In contrast, vascular remodelling was not apparent in aged mice exposed to CIH. Furthermore, left ventricular perivascular fibrosis (mean change: 0.71 ± 0.1; P < 0.001) and hypertrophy (mean change: 0.17 ± 0.1; P = 0.038) were increased by CIH exposure in young mice, but not in aged mice. Principal component analysis identified similar cardiovascular alterations among the young mice exposed to CIH and both older mouse groups, suggesting that CIH induces premature cardiovascular senescence. CONCLUSION Cardiovascular remodelling induced by severe CIH is affected by the age at which CIH onset occurs, suggesting that the deleterious cardiovascular effects associated with CIH may be more pronounced in younger populations, and such changes resemble chronological age-related declines in cardiovascular structural integrity.
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Affiliation(s)
- Anabel L Castro-Grattoni
- Group of Translational Research in Respiratory Medicine, Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, Lleida, Spain.,IRB Lleida, University of Lleida, Lleida, Spain
| | | | - Ivan Benitez
- Group of Translational Research in Respiratory Medicine, Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, Lleida, Spain.,IRB Lleida, University of Lleida, Lleida, Spain
| | - Marta Torres
- Laboratori del son, Servei de Pneumologia, Hospital Clínic, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Isaac Almendros
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Ramon Farre
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Josep M Montserrat
- Laboratori del son, Servei de Pneumologia, Hospital Clínic, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Mireia Dalmases
- Group of Translational Research in Respiratory Medicine, Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, Lleida, Spain.,IRB Lleida, University of Lleida, Lleida, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - David Gozal
- Department of Child Health, University of Missouri, School of Medicine, Columbia, MO, USA
| | - Manuel Sánchez-de-la-Torre
- Group of Translational Research in Respiratory Medicine, Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, Lleida, Spain.,IRB Lleida, University of Lleida, Lleida, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain
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17
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Obstructive sleep apnea is associated with increased coronary plaque instability: an optical frequency domain imaging study. Heart Vessels 2019; 34:1266-1279. [PMID: 30790035 PMCID: PMC6620247 DOI: 10.1007/s00380-019-01363-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 02/15/2019] [Indexed: 12/13/2022]
Abstract
Obstructive sleep apnea (OSA) is associated with coronary artery disease (CAD) and with an increased risk for myocardial infarction, stroke or death due to cardiovascular disease. Optical frequency-domain imaging (OFDI) is a useful modality for evaluating the characteristics of atherosclerotic plaque. The purpose of the study was to use OFDI to investigate the association of OSA with coronary plaque characteristics in patients undergoing percutaneous coronary intervention (PCI). We retrospectively analyzed OFDI data for coronary artery plaques from 15 patients with OSA and 35 non–OSA patients treated between October 2015 and October 2018. Plaque morphology was evaluated for 70 lesions, including 21 from patients with OSA and 49 from non–OSA patients. Compared with the non–OSA group, patients with OSA had significantly higher prevalences of thinned cap fibroatheroma (TCFA) (67% vs. 35%, P = 0.014) and microchannels (86% vs. 55%, P = 0.014); a significantly higher mean lipid index (1392 ± 982 vs. 817 ± 699, P = 0.021), macrophage grade (8.4 ± 6.4 vs. 4.8 ± 4.5, P = 0.030), and maximum number of microchannels (1.5 ± 1.0 vs. 0.7 ± 0.7, P = 0.001); and a significantly lower mean minimum fibrous cap thickness (69.4 ± 28.7 vs. 96.1 ± 51.8 μm, P = 0.008). This OFDI analysis suggests that OSA is associated with unstable plaque characteristics in patients with CAD. More intensive medical management for stabilization of coronary atherosclerotic plaque is required in patients with OSA.
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18
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Abstract
Obstructive sleep apnoea (OSA) is recognized as a major public health burden conveying a significant risk of cardiovascular diseases (CVD) and mortality. Continuous positive airway pressure (CPAP) is the treatment of choice for the majority of patients with OSA but the benefit of CPAP on CVD is uncertain. Thus, a greater understanding of the mechanisms by which OSA leads to CVD might identify novel therapeutic approaches. Intermittent hypoxia (IH), a hallmark feature of OSA, plays a key role in the pathogenesis and experimental studies using animal and cell culture studies suggest that IH mediates CVD through activation of multiple mechanistic pathways such as sympathetic excitation, inflammation, oxidative stress or metabolic dysregulation. Recurrent arousals, intrathoracic pressure swings and concomitant obesity likely play important additive roles in this process. In this review, the available evidence of the pathophysiological mechanisms of CVD in OSA is explored with a specific emphasis on IH, recurrent arousals and intrathoracic pressure swings as the main pathophysiological triggers.
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Affiliation(s)
- Silke Ryan
- Pulmonary and Sleep Disorders Unit, St. Vincent's University Hospital, Dublin, Ireland.,School of Medicine, University College Dublin, Dublin, Ireland
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19
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Farré N, Otero J, Falcones B, Torres M, Jorba I, Gozal D, Almendros I, Farré R, Navajas D. Intermittent Hypoxia Mimicking Sleep Apnea Increases Passive Stiffness of Myocardial Extracellular Matrix. A Multiscale Study. Front Physiol 2018; 9:1143. [PMID: 30158879 PMCID: PMC6104184 DOI: 10.3389/fphys.2018.01143] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/30/2018] [Indexed: 12/14/2022] Open
Abstract
Background: Tissue hypoxia-reoxygenation characterizes obstructive sleep apnea (OSA), a very prevalent respiratory disease associated with increased cardiovascular morbidity and mortality. Experimental studies indicate that intermittent hypoxia (IH) mimicking OSA induces oxidative stress and inflammation in heart tissue at the cell and molecular levels. However, it remains unclear whether IH modifies the passive stiffness of the cardiac tissue extracellular matrix (ECM). Aim: To investigate multiscale changes of stiffness induced by chronic IH in the ECM of left ventricular (LV) myocardium in a murine model of OSA. Methods: Two-month and 18-month old mice (N = 10 each) were subjected to IH (20% O2 40 s-6% O2 20 s) for 6 weeks (6 h/day). Corresponding control groups for each age were kept under normoxia. Fresh LV myocardial strips (∼7 mm × 1 mm × 1 mm) were prepared, and their ECM was obtained by decellularization. Myocardium ECM macroscale mechanics were measured by performing uniaxial stress-strain tensile tests. Strip macroscale stiffness was assessed as the stress value (σ) measured at 0.2 strain and Young's modulus (EM) computed at 0.2 strain by fitting Fung's constitutive model to the stress-strain relationship. ECM stiffness was characterized at the microscale as the Young's modulus (Em) measured in decellularized tissue slices (∼12 μm tick) by atomic force microscopy. Results: Intermittent hypoxia induced a ∼1.5-fold increase in σ (p < 0.001) and a ∼2.5-fold increase in EM (p < 0.001) of young mice as compared with normoxic controls. In contrast, no significant differences emerged in Em among IH-exposed and normoxic mice. Moreover, the mechanical effects of IH on myocardial ECM were similar in young and aged mice. Conclusion: The marked IH-induced increases in macroscale stiffness of LV myocardium ECM suggests that the ECM plays a role in the cardiac dysfunction induced by OSA. Furthermore, absence of any significant effects of IH on the microscale ECM stiffness suggests that the significant increases in macroscale stiffening are primarily mediated by 3D structural ECM remodeling.
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Affiliation(s)
- Núria Farré
- Heart Failure Unit, Department of Cardiology, Hospital del Mar, Barcelona, Spain.,Heart Diseases Biomedical Research Group, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain.,Department of Medicine, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Jorge Otero
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - Bryan Falcones
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - Marta Torres
- CIBER de Enfermedades Respiratorias, Madrid, Spain.,Sleep Lab, Hospital Clinic of Barcelona, Barcelona, Spain
| | - Ignasi Jorba
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - David Gozal
- Department of Child Health, University of Missouri School of Medicine, Columbia, MO, United States
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,CIBER de Enfermedades Respiratorias, Madrid, Spain.,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
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20
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Trzepizur W, Cortese R, Gozal D. Murine models of sleep apnea: functional implications of altered macrophage polarity and epigenetic modifications in adipose and vascular tissues. Metabolism 2018; 84:44-55. [PMID: 29154950 PMCID: PMC5955762 DOI: 10.1016/j.metabol.2017.11.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/08/2017] [Accepted: 11/10/2017] [Indexed: 02/07/2023]
Abstract
Obstructive sleep apnea (OSA) is a highly prevalent disease across the lifespan, is characterized by chronic intermittent hypoxia and sleep fragmentation, and has been independently associated with substantial cardiometabolic morbidity. However, the reversibility of end-organ morbidity with treatment is not always apparent, suggesting that both tissue remodeling and epigenetic mechanisms may be operationally involved. Here, we review the cumulative evidence focused around murine models of OSA to illustrate the temporal dependencies of cardiometabolic dysfunction and its reversibility, and more particularly to discuss the critical contributions of tissue macrophages to adipose tissue insulin resistance and vascular atherogenesis. In addition, we describe initial findings potentially implicating epigenetic alterations in both the emergence of the cardiometabolic morbidity of OSA, and in its reversibility with treatment. We anticipate that improved understanding of macrophage biology and epigenetics in the context of intermittent hypoxia and sleep fragmentation will lead to discovery of novel therapeutic targets and improved cardiovascular and metabolic outcomes in OSA.
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Affiliation(s)
- Wojciech Trzepizur
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, United States; Département de Pneumologie, Centre de Recherche Clinique, CHU d'Angers, Université Bretagne Loire, UNIV Angers, INSERM UMR 1063, Angers, France
| | - Rene Cortese
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, United States
| | - David Gozal
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, United States.
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21
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Suarez-Giron MC, Castro-Grattoni A, Torres M, Farré R, Barbé F, Sánchez-de-la-Torre M, Gozal D, Picado C, Montserrat JM, Almendros I. Acetylsalicylic Acid Prevents Intermittent Hypoxia-Induced Vascular Remodeling in a Murine Model of Sleep Apnea. Front Physiol 2018; 9:600. [PMID: 29881356 PMCID: PMC5976862 DOI: 10.3389/fphys.2018.00600] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 05/03/2018] [Indexed: 12/16/2022] Open
Abstract
Study objectives: Chronic intermittent hypoxia (CIH), a hallmark feature of obstructive sleep apnea (OSA), induces accelerated atherogenesis as well as aorta vascular remodeling. Although the cyclooxygenase (COX) pathway has been proposed to contribute to the cardiovascular consequences of OSA, the potential benefits of a widely employed COX-inhibitor such (acetylsalicylic acid, ASA) on CIH-induced vascular pathology are unknown. Therefore, we hypothesized that a common non-selective COX inhibitor such as ASA would attenuate the aortic remodeling induced by CIH in mice. Methods: 40 wild-type C57/BL6 male mice were randomly allocated to CIH or normoxic exposures (N) and treated with daily doses of ASA or placebo for 6 weeks. At the end of the experiments, intima-media thickness (IMT), elastin disorganization (ED), elastin fragmentation (EF), length between fragmented fiber endpoints (LFF), aortic wall collagen abundance (AC) and mucoid deposition (MD) were assessed. Results: Compared to N, CIH promoted significant increases in IMT (52.58 ± 2.82 μm vs. 46.07 ± 4.18 μm, p < 0.003), ED (25.29 ± 14.60% vs. 4.74 ± 5.37%, p < 0.001), EF (5.80 ± 2.04 vs. 3.06 ± 0.58, p < 0.001), LFF (0.65 ± 0.34% vs. 0.14 ± 0.09%, p < 0.001), AC (3.43 ± 1.52% vs. 1.67 ± 0.67%, p < 0.001) and MD (3.40 ± 2.73 μm2 vs. 1.09 ± 0.72 μm2, p < 0.006). ASA treatment mitigated the CIH-induced alterations in IMT: 44.07 ± 2.73 μm; ED: 10.57 ± 12.89%; EF: 4.63 ± 0.88; LFF: 0.25 ± 0.17% and AC: 0.90 ± 0.13% (p<0.05 for all comparisons). Conclusions: ASA prevents the CIH-induced aortic vascular remodeling, and should therefore be prospectively evaluated as adjuvant treatment in patients with OSA.
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Affiliation(s)
| | - Anabel Castro-Grattoni
- Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, IRB Lleida, University of Lleida, Lleida, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Marta Torres
- Laboratori del Son, Servei de Pneumologia, Hospital Clínic, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Ramon Farré
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Ferran Barbé
- Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, IRB Lleida, University of Lleida, Lleida, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Manuel Sánchez-de-la-Torre
- Respiratory Department, Hospital University Arnau de Vilanova and Santa Maria, IRB Lleida, University of Lleida, Lleida, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - David Gozal
- Section of Pediatric Sleep Medicine, Biological Sciences Division, Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL, United States
| | - Cesar Picado
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain.,Department of Pneumology and Respiratory Allergy, Hospital Clinic, Barcelona, Spain
| | - Josep M Montserrat
- Laboratori del Son, Servei de Pneumologia, Hospital Clínic, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Isaac Almendros
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
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22
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Tempaku PF, Mazzotti DR, Hirotsu C, Andersen ML, Xavier G, Maurya PK, Rizzo LB, Brietzke E, Belangero SI, Bittencourt L, Tufik S. The effect of the severity of obstructive sleep apnea syndrome on telomere length. Oncotarget 2018; 7:69216-69224. [PMID: 27690344 PMCID: PMC5342471 DOI: 10.18632/oncotarget.12293] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/23/2016] [Indexed: 12/17/2022] Open
Abstract
Aging is associated with an increase in the prevalence of obstructive sleep apnea syndrome (OSAS) as well as the shortening of telomeres. It is known that OSAS-related factors are stimuli that can contribute to the acceleration of cellular senescence. Thus, the present study aimed to compare the leukocyte telomere length (LTL) between OSAS patients and controls, as well as to verify the correlation between LTL and sleep parameters. We used DNA extracted of 928 individuals from EPISONO to measure the LTL by the quantitative real-time polymerase chain reaction. All individuals were subjected to one full-night polysomnography. LTL was significantly shorter in OSAS patients compared to controls. The results showed negative correlations between LTL and the following variables: apnea-hypopnea index, respiratory disturbance index, desaturation index and wake after sleep onset. LTL was positively correlated with sleep efficiency, total sleep time, basal, minimum and maximum oxygen saturation. Lastly, it was observed that OSAS severity was associated with shorter LTL even after adjusting for sex, age, years of schooling, body mass index, diabetes, stroke and heart attack. In conclusion, our study indicates the presence of an association between LTL and OSAS and a significant impact of severity of OSAS in telomeres shortening.
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Affiliation(s)
- Priscila Farias Tempaku
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Diego Robles Mazzotti
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Camila Hirotsu
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Monica Levy Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Gabriela Xavier
- Laboratório Interdisciplinar de Neurociências Clínicas (LINC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.,Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Pawan Kumar Maurya
- Laboratório Interdisciplinar de Neurociências Clínicas (LINC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.,Amity Institute of Biotechnology, Amity University Uttar Pradesh, Noida, India
| | - Lucas Bortolotto Rizzo
- Laboratório Interdisciplinar de Neurociências Clínicas (LINC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.,Department of Psychiatry, University of Tuebingen, Tuebingen, Germany.,Grupo de Pesquisa em Neurociência Comportamental e Molecular do Transtorno Bipolar, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Elisa Brietzke
- Laboratório Interdisciplinar de Neurociências Clínicas (LINC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.,Grupo de Pesquisa em Neurociência Comportamental e Molecular do Transtorno Bipolar, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Sintia Iole Belangero
- Laboratório Interdisciplinar de Neurociências Clínicas (LINC), Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil.,Departamento de Morfologia e Genética, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Lia Bittencourt
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brasil
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23
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Zhang GH, Yu FC, Li Y, Wei Q, Song SS, Zhou FP, Tong JY. Prolyl 4-Hydroxylase Domain Protein 3 Overexpression Improved Obstructive Sleep Apnea-Induced Cardiac Perivascular Fibrosis Partially by Suppressing Endothelial-to-Mesenchymal Transition. J Am Heart Assoc 2017; 6:e006680. [PMID: 29051216 PMCID: PMC5721870 DOI: 10.1161/jaha.117.006680] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 09/15/2017] [Indexed: 01/19/2023]
Abstract
BACKGROUND Intermittent hypoxia (IH) induced by obstructive sleep apnea is the key factor involved in cardiovascular fibrosis. Under persistent hypoxia condition, endothelial cells respond by endothelial-to-mesenchymal transition (EndMT), which is associated with cardiovascular fibrosis. Prolyl 4-hydroxylase domain protein 3 (PHD3) is a cellular oxygen sensor and its expression increased in hypoxia. However, its role in obstructive sleep apnea-induced EndMT and cardiovascular fibrosis is still uncertain. We investigated the potential mechanism of obstructive sleep apnea-induced cardiac perivascular fibrosis and the role of PHD3 in it. METHODS AND RESULTS In vivo, C56BL/6 mice were exposed to IH for 12 weeks. PHD3 expression was changed by lentivirus-mediated short-hairpin PHD3 and lentivirus carrying PHD3 cDNA. EndMT related protein levels, histological and functional parameters were detected after 12 weeks. In vitro, human umbilical vein endothelial cells were treated with IH/short-hairpin PHD3/lentivirus carrying PHD3 cDNA to explore the mechanism of PHD3 in altered function of human umbilical vein endothelial cells. We found that chronic intermittent hypoxia increase PHD3 expression and EndMT. In vivo, IH accelerate cardiac dysfunction and aggravate collagen deposition via the process of EndMT. And, when PHD3 were overexpressed, cardiac dysfunction and collagen excessive deposition were improved. In vitro, IH induced EndMT, which endow human umbilical vein endothelial cells spindle morphology and an enhanced ability to migration and collagen secretion. PHD3 overexpression in cultured human umbilical vein endothelial cells ameliorated IH-induced EndMT through inactivating hypoxia-inducible factor 1 alpha and small mothers against decapentaplegic 2 and 3. CONCLUSIONS Obstructive sleep apnea-induced cardiac perivascular fibrosis is associated with EndMT, and PHD3 overexpression might be beneficial in the prevention of it by inhibiting EndMT. PHD3 overexpression might have therapeutic potential in the treatment of the disease.
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Affiliation(s)
- Guang-Hao Zhang
- Southeast University, Nanjing, Jiangsu, China
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Fu-Chao Yu
- Southeast University, Nanjing, Jiangsu, China
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Yang Li
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Qin Wei
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Song-Song Song
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Fang-Ping Zhou
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
| | - Jia-Yi Tong
- Southeast University, Nanjing, Jiangsu, China
- Department of Cardiology, Zhongda Hospital Affiliated to Southeast University, Nanjing, Jiangsu, China
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24
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Khalyfa A, Qiao Z, Gileles-Hillel A, Khalyfa AA, Akbarpour M, Popko B, Gozal D. Activation of the Integrated Stress Response and Metabolic Dysfunction in a Murine Model of Sleep Apnea. Am J Respir Cell Mol Biol 2017; 57:477-486. [PMID: 28594573 DOI: 10.1165/rcmb.2017-0057oc] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Intermittent hypoxia (IH) induces activation of the integrated stress response (ISR), but its role in IH-induced visceral white adipose tissue (vWAT) insulin resistance is unknown. CHOP is activated by chronic ISR, whereas GADD34 dephosphorylates the subunit of translation initiation factor 2 (eIF2α), leading to termination of the ISR. We hypothesized that CHOP/Gadd34 null mice would not manifest evidence of insulin resistance after IH exposures. Eight-week-old CHOP/GADD34-/- (double mutant [DM]) and wild-type (WT) littermates were randomly assigned to IH or room air (RA) exposures for 6 weeks. Glucose and insulin tolerance tests were performed, and regulatory T cells (Tregs) and macrophages in vWAT were assessed. Phosphorylated eIF2α:total eIF2α, ATF4, XBP1 expression, and insulin-induced pAKT/AKT expression changes were examined in vWATs. Single GADD34-/- and PERK+/- mice were also evaluated. Body weight and vWAT mass were reduced in DM and WT mice after IH. M1/M2 macrophages and inflammatory macrophages (Ly-6chigh) were significantly increased in WT vWAT but remained unchanged in DM mice. Tregs were significantly decreased in WT vWAT but not in DM mice. Systemic insulin and glucose tolerance tests revealed insulin resistance in IH-WT but not in IH-DM mice. Similarly, decreased pAKT/AKT responses to exogenous insulin emerged in IH-WT compared with RA-WT mice, whereas no significant differences emerged in IH-DM compared with DM-RA. Chronic ISR activation appears to contribute to the insulin resistance and vWAT inflammation that characteristically emerge after long-term IH exposures in a murine model of obstructive sleep apnea.
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Affiliation(s)
- Abdelnaby Khalyfa
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, and
| | - Zhuanhong Qiao
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, and
| | | | - Ahamed A Khalyfa
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, and
| | - Mahzad Akbarpour
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, and
| | - Brian Popko
- 2 Department of Neurology, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, Illinois
| | - David Gozal
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, and
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25
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Akbarpour M, Khalyfa A, Qiao Z, Gileles-Hillel A, Almendros I, Farré R, Gozal D. Altered CD8+ T-Cell Lymphocyte Function and TC1 Cell Stemness Contribute to Enhanced Malignant Tumor Properties in Murine Models of Sleep Apnea. Sleep 2017; 40:2667754. [PMID: 28364502 DOI: 10.1093/sleep/zsw040] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Study Objective The presence of obstructive sleep apnea (OSA) in patients with cancer appears to be accompanied by poorer outcomes. However, the mechanisms underlying such association are unknown. Tumor infiltrating lymphocytes (TILs), including CD8+ T cells, function as cytotoxic T lymphocytes (CTLs) and mount immune responses to cancer by the release of cytolytic enzymes, including granzyme B (GzmB), perforin (Prf), and cytokines such as interferon (IFN)-γ. Methods Using established in vivo mouse models, we investigated CD8+ T cells and cancer stem cells (CSCs) in intermittent hypoxia (IH) and sleep fragmentation (SF) in the context of tumor environment. Results Both IH and SF promoted increased tumor growth and invasion toward adjacent tissues compared to controls. The number and frequency of GzmB-producing CD8+ T cells per milligram of tumor tissue was significantly reduced in IH-exposed mice with impaired cytolytic function in both the groups and correlated with tumor weight. We also found that Oct4+ and CD44+CD133+ expressing CSCs were considerably increased in IH and SF tumors, respectively. Conclusions Reductions in GzmB in intratumoral CD8+ T cells in combination with the changes in tumor microenvironment that maintain the ability of CSCs to self-renew and even confer this capability to the nonstem population are compatible with reduced immunosurveillance and adverse tumor outcomes in animal models of OSA.
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Affiliation(s)
- Mahzad Akbarpour
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - Abdelnaby Khalyfa
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - Zhuanghong Qiao
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - Alex Gileles-Hillel
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL
| | - Isaac Almendros
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL.,Unitat Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-CIBERES-IDIBAPS, Barcelona, Spain
| | - Ramon Farré
- Unitat Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-CIBERES-IDIBAPS, Barcelona, Spain
| | - David Gozal
- Department of Pediatrics, Pritzker School of Medicine, The University of Chicago, Chicago, IL
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26
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Khalyfa A, Kheirandish-Gozal L, Gozal D. Circulating exosomes in obstructive sleep apnea as phenotypic biomarkers and mechanistic messengers of end-organ morbidity. Respir Physiol Neurobiol 2017; 256:143-156. [PMID: 28676332 DOI: 10.1016/j.resp.2017.06.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 06/13/2017] [Accepted: 06/19/2017] [Indexed: 02/08/2023]
Abstract
Obstructive sleep apnea (OSA), the most severe form of sleep disordered breathing, is characterized by intermittent hypoxia during sleep (IH), sleep fragmentation, and episodic hypercapnia. OSA is associated with increased risk for morbidity and mortality affecting cardiovascular, metabolic, and neurocognitive systems, and more recently with non-alcoholic fatty liver disease (NAFLD) and cancer-related deaths. Substantial variability in OSA outcomes suggests that genetically-determined and environmental and lifestyle factors affect the phenotypic susceptibility to OSA. Furthermore, OSA and obesity often co-exist and manifest activation of shared molecular end-organ injury mechanisms that if properly identified may represent potential therapeutic targets. A challenge in the development of non-invasive diagnostic assays in body fluids is the ability to identify clinically relevant biomarkers. Circulating extracellular vesicles (EVs) include a heterogeneous population of vesicular structures including exosomes, prostasomes, microvesicles (MVs), ectosomes and oncosomes, and are classified based on their size, shape and membrane surface composition. Of these, exosomes (30-100nm) are very small membrane vesicles derived from multi-vesicular bodies or from the plasma membrane and play important roles in mediating cell-cell communication via cargo that includes lipids, proteins, mRNAs, miRNAs and DNA. We have recently identified a unique cluster of exosomal miRNAs in both humans and rodents exposed to intermittent hypoxia as well as in patients with OSA with divergent morbid phenotypes. Here we summarize such recent findings, and will focus on exosomal miRNAs in both adult and children which mediate intercellular communication relevant to OSA and endothelial dysfunction, and their potential value as diagnostic and prognostic biomarkers.
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Affiliation(s)
- Abdelnaby Khalyfa
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA.
| | - Leila Kheirandish-Gozal
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - David Gozal
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
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27
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Gozal D, Gileles-Hillel A, Cortese R, Li Y, Almendros I, Qiao Z, Khalyfa AA, Andrade J, Khalyfa A. Visceral White Adipose Tissue after Chronic Intermittent and Sustained Hypoxia in Mice. Am J Respir Cell Mol Biol 2017; 56:477-487. [PMID: 28107636 DOI: 10.1165/rcmb.2016-0243oc] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Angiogenesis, a process induced by hypoxia in visceral white adipose tissues (vWAT) in the context of obesity, mediates obesity-induced metabolic dysfunction and insulin resistance. Chronic intermittent hypoxia (IH) and sustained hypoxia (SH) induce body weight reductions and insulin resistance of different magnitudes, suggesting different hypoxia inducible factor (HIF)-1α-related activity. Eight-week-old male C57BL/6J mice (n = 10-12/group) were exposed to either IH, SH, or room air (RA). vWAT were analyzed for insulin sensitivity (phosphorylated (pAKT)/AKT), HIF-1α transcription using chromatin immunoprecipitation (ChIP)-sequencing, angiogenesis using immunohistochemistry, and gene expression of different fat cell markers and HIF-1α gene targets using quantitative polymerase chain reaction or microarrays. Body and vWAT weights were reduced in hypoxia (SH > IH > RA; P < 0.001), with vWAT in IH manifesting vascular rarefaction and increased proinflammatory macrophages. HIF-1α ChIP-sequencing showed markedly increased binding sites in SH-exposed vWAT both at 6 hours and at 6 weeks compared with IH, the latter also showing decreased vascular endothelial growth factor, endothelial nitric oxide synthase, P2RX5, and PAT2 expression, and insulin resistance (IH > > > SH = RA; P < 0.001). IH induces preferential whitening of vWAT, as opposed to prominent browning in SH. Unlike SH, IH elicits early HIF-1α activity that is unsustained over time and is accompanied by concurrent vascular rarefaction, inflammation, and insulin resistance. Thus, the dichotomous changes in HIF-1α transcriptional activity and brown/beige/white fat balance in IH and SH should enable exploration of mechanisms by which altered sympathetic outflow, such as that which occurs in apneic patients, results in whitening, rather than the anticipated browning of adipose tissues that occurs in SH.
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Affiliation(s)
- David Gozal
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
| | - Alex Gileles-Hillel
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
| | - Rene Cortese
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
| | - Yan Li
- 2 Center for Research Informatics, Biological Sciences Division, The University of Chicago, Chicago, Illinois
| | - Isaac Almendros
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and.,3 Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-IDIBAPS, Barcelona, Spain; and.,4 CIBER de Enfermedades Respiratorias, Barcelona, Spain
| | - Zhuanhong Qiao
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
| | - Ahamed A Khalyfa
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
| | - Jorge Andrade
- 2 Center for Research Informatics, Biological Sciences Division, The University of Chicago, Chicago, Illinois
| | - Abdelnaby Khalyfa
- 1 Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, and
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28
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Gileles-Hillel A, Almendros I, Khalyfa A, Nigdelioglu R, Qiao Z, Hamanaka RB, Mutlu GM, Akbarpour M, Gozal D. Prolonged Exposures to Intermittent Hypoxia Promote Visceral White Adipose Tissue Inflammation in a Murine Model of Severe Sleep Apnea: Effect of Normoxic Recovery. Sleep 2017; 40:2731734. [PMID: 28329220 DOI: 10.1093/sleep/zsw074] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Study Objective Increased visceral white adipose tissue (vWAT) mass results in infiltration of inflammatory macrophages that drive inflammation and insulin resistance. Patients with obstructive sleep apnea (OSA) suffer from increased prevalence of obesity, insulin resistance, and metabolic syndrome. Murine models of intermittent hypoxia (IH) mimicking moderate-severe OSA manifest insulin resistance following short-term IH. We examined in mice the effect of long-term IH on the inflammatory cellular changes within vWAT and the potential effect of normoxic recovery (IH-R). Methods Male C57BL/6J mice were subjected to IH for 20 weeks, and a subset was allowed to recover in room air (RA) for 6 or 12 weeks (IH-R). Stromal vascular fraction was isolated from epididymal vWAT and mesenteric vWAT depots, and single-cell suspensions were prepared for flow cytometry analyses, reactive oxygen species (ROS), and metabolic assays. Results IH reduced body weight and vWAT mass and IH-R resulted in catch-up weight and vWAT mass. IH-exposed vWAT exhibited increased macrophage counts (ATMs) that were only partially improved in IH-R. IH also caused a proinflammatory shift in ATMs (increased Ly6c(hi)(+) and CD36(+) ATMs). These changes were accompanied by increased vWAT insulin resistance with only partial improvements in IH-R. In addition, ATMs exhibited increased ROS production, altered metabolism, and changes in electron transport chain, which were only partially improved in IH-R. Conclusion Prolonged exposures to IH during the sleep period induce pronounced vWAT inflammation and insulin resistance despite concomitant vWAT mass reductions. These changes are only partially reversible after 3 months of normoxic recovery. Thus, long-lasting OSA may preclude complete reversibility of metabolic changes.
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Affiliation(s)
- Alex Gileles-Hillel
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Isaac Almendros
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Abdelnaby Khalyfa
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Recep Nigdelioglu
- Department of Medicine, Section of Pulmonary and Critical Care, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Zhuanhong Qiao
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Robert B Hamanaka
- Department of Medicine, Section of Pulmonary and Critical Care, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Gökhan M Mutlu
- Department of Medicine, Section of Pulmonary and Critical Care, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - Mahzad Akbarpour
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
| | - David Gozal
- Sections of Pediatric Sleep Medicine and Pulmonology, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL
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Cortese R, Gileles-Hillel A, Khalyfa A, Almendros I, Akbarpour M, Khalyfa AA, Qiao Z, Garcia T, Andrade J, Gozal D. Aorta macrophage inflammatory and epigenetic changes in a murine model of obstructive sleep apnea: Potential role of CD36. Sci Rep 2017; 7:43648. [PMID: 28240319 PMCID: PMC5327416 DOI: 10.1038/srep43648] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/25/2017] [Indexed: 12/15/2022] Open
Abstract
Obstructive sleep apnea (OSA) affects 8-10% of the population, is characterized by chronic intermittent hypoxia (CIH), and causally associates with cardiovascular morbidities. In CIH-exposed mice, closely mimicking the chronicity of human OSA, increased accumulation and proliferation of pro-inflammatory metabolic M1-like macrophages highly expressing CD36, emerged in aorta. Transcriptomic and MeDIP-seq approaches identified activation of pro-atherogenic pathways involving a complex interplay of histone modifications in functionally-relevant biological pathways, such as inflammation and oxidative stress in aorta macrophages. Discontinuation of CIH did not elicit significant improvements in aorta wall macrophage phenotype. However, CIH-induced aorta changes were absent in CD36 knockout mice, Our results provide mechanistic insights showing that CIH exposures during sleep in absence of concurrent pro-atherogenic settings (i.e., genetic propensity or dietary manipulation) lead to the recruitment of CD36(+)high macrophages to the aortic wall and trigger atherogenesis. Furthermore, long-term CIH-induced changes may not be reversible with usual OSA treatment.
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Affiliation(s)
- Rene Cortese
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Alex Gileles-Hillel
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Abdelnaby Khalyfa
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Isaac Almendros
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Mahzad Akbarpour
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Ahamed A Khalyfa
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Zhuanghong Qiao
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
| | - Tzintzuni Garcia
- Center for Research Informatics, The University of Chicago, Chicago, IL, USA
| | - Jorge Andrade
- Center for Research Informatics, The University of Chicago, Chicago, IL, USA
| | - David Gozal
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA
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Gemel J, Su Z, Gileles-Hillel A, Khalyfa A, Gozal D, Beyer EC. Intermittent hypoxia causes NOX2-dependent remodeling of atrial connexins. BMC Cell Biol 2017; 18:7. [PMID: 28124622 PMCID: PMC5267331 DOI: 10.1186/s12860-016-0117-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Obstructive sleep apnea has been linked to the development of heart disease and arrhythmias, including atrial fibrillation. Since altered conduction through gap junction channels can contribute to the pathogenesis of such arrhythmias, we examined the abundance and distributions of the major cardiac gap junction proteins, connexin40 (Cx40) and connexin43 (Cx43) in mice treated with sleep fragmentation or intermittent hypoxia (IH) as animal models of the components of obstructive sleep apnea. RESULTS Wild type C57BL/6 mice or mice lacking NADPH 2 (NOX2) oxidase activity (gp91phox(-/Y)) were exposed to room air or to SF or IH for 6 weeks. Then, the mice were sacrificed, and atria and ventricles were immediately dissected. The abundances of Cx40 or Cx43 in atria and ventricles were unaffected by SF. In contrast, immunoblots showed that the abundance of atrial Cx40 and Cx43 and ventricular Cx43 were reduced in mice exposed to IH. qRT-PCR demonstrated significant reductions of atrial Cx40 and Cx43 mRNAs. Immunofluorescence microscopy revealed that the abundance and size of gap junctions containing Cx40 or Cx43 were reduced in atria by IH treatment of mice. However, no changes of connexin abundance or gap junction size/abundance were observed in IH-treated NOX2-null mice. CONCLUSIONS These results demonstrate that intermittent hypoxia (but not sleep fragmentation) causes reductions and remodeling of atrial Cx40 and Cx43. These alterations may contribute to the substrate for atrial fibrillation that develops in response to obstructive sleep apnea. Moreover, these connexin changes are likely generated in response to reactive oxygen species generated by NOX2.
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Affiliation(s)
- Joanna Gemel
- Department of Pediatrics, University of Chicago, 900 E. 57th St. KCBD 5152, Chicago, IL, 60637, USA
| | - Zihan Su
- Present address: Williams College, Williamstown, MA, USA
| | - Alex Gileles-Hillel
- Present address: Department of Pediatrics, Hadassah-Hebrew University Medical Center, Mt. Scopus, Jerusalem, Israel
| | - Abdelnaby Khalyfa
- Department of Pediatrics, University of Chicago, 900 E. 57th St. KCBD 5152, Chicago, IL, 60637, USA
| | - David Gozal
- Department of Pediatrics, University of Chicago, 900 E. 57th St. KCBD 5152, Chicago, IL, 60637, USA
| | - Eric C Beyer
- Department of Pediatrics, University of Chicago, 900 E. 57th St. KCBD 5152, Chicago, IL, 60637, USA.
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Turnbull CD, Rossi VA, Santer P, Schwarz EI, Stradling JR, Petousi N, Kohler M. Effect of OSA on hypoxic and inflammatory markers during CPAP withdrawal: Further evidence from three randomized control trials. Respirology 2016; 22:793-799. [PMID: 27860068 DOI: 10.1111/resp.12946] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/08/2016] [Accepted: 09/08/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND OBJECTIVE Obstructive sleep apnoea (OSA) is associated with cardiovascular disease. Intermittent hypoxia, endothelial dysfunction and adipose tissue-mediated inflammation have all been linked to cardiovascular disease in OSA. We therefore explored the effect of OSA on relevant associated blood markers: adrenomedullin (ADM), endocan, endothelin-1 (ET-1), resistin and vascular endothelial growth factor (VEGF). METHODS Patients with OSA, established on and compliant with continuous positive airways pressure (CPAP) therapy for >1 year were included from three randomized controlled trials, conducted at two centres. Patients were randomized to either continued therapeutic CPAP or sham CPAP (CPAP withdrawal) for 2 weeks. Blood markers were measured at baseline and at 14 days and the treatment effect between sham CPAP and therapeutic CPAP was analysed. RESULTS A total of 109 patients were studied (therapeutic CPAP n = 54, sham CPAP n = 55). Sham CPAP was associated with a return of OSA (between-group difference in oxygen desaturation index (ODI) 36.0/h, 95% CI 29.9-42.2, P < 0.001). Sham CPAP was associated with a reduction in ADM levels at 14 days (-26.0 pg/mL, 95% CI -47.8 to -4.3, P = 0.02), compared to therapeutic CPAP. Return of OSA was not associated with changes in endocan, ET-1, resistin or VEGF. CONCLUSION Whilst CPAP withdrawal was associated with return of OSA, it was associated with an unexpected significant reduction in the vasodilator ADM and not with expected increases in hypoxia-induced markers, markers of endothelial function or resistin. We propose that the vascular effects occurring in OSA may be brought about by other mechanisms, perhaps partly through a reduction in ADM.
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Affiliation(s)
- Chris D Turnbull
- Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.,NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Valentina A Rossi
- Division of Pulmonology and Sleep Disorders Center, University Hospital of Zurich, Zurich, Switzerland
| | - Peter Santer
- NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Esther I Schwarz
- Division of Pulmonology and Sleep Disorders Center, University Hospital of Zurich, Zurich, Switzerland
| | - John R Stradling
- Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.,NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Nayia Petousi
- Oxford Centre for Respiratory Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Malcolm Kohler
- Division of Pulmonology and Sleep Disorders Center, University Hospital of Zurich, Zurich, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
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Campillo N, Jorba I, Schaedel L, Casals B, Gozal D, Farré R, Almendros I, Navajas D. A Novel Chip for Cyclic Stretch and Intermittent Hypoxia Cell Exposures Mimicking Obstructive Sleep Apnea. Front Physiol 2016; 7:319. [PMID: 27524971 PMCID: PMC4965455 DOI: 10.3389/fphys.2016.00319] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 07/13/2016] [Indexed: 11/13/2022] Open
Abstract
Intermittent hypoxia (IH), a hallmark of obstructive sleep apnea (OSA), plays a critical role in the pathogenesis of OSA-associated morbidities, especially in the cardiovascular and respiratory systems. Oxidative stress and inflammation induced by IH are suggested as main contributors of end-organ dysfunction in OSA patients and animal models. Since the molecular mechanisms underlying these in vivo pathological responses remain poorly understood, implementation of experimental in vitro cell-based systems capable of inducing high-frequency IH would be highly desirable. Here, we describe the design, fabrication, and validation of a versatile chip for subjecting cultured cells to fast changes in gas partial pressure and to cyclic stretch. The chip is fabricated with polydimethylsiloxane (PDMS) and consists of a cylindrical well-covered by a thin membrane. Cells cultured on top of the membrane can be subjected to fast changes in oxygen concentration (equilibrium time ~6 s). Moreover, cells can be subjected to cyclic stretch at cardiac or respiratory frequencies independently or simultaneously. Rat bone marrow-derived mesenchymal stem cells (MSCs) exposed to IH mimicking OSA and cyclic stretch at cardiac frequencies revealed that hypoxia-inducible factor 1α (HIF-1α) expression was increased in response to both stimuli. Thus, the chip provides a versatile tool for the study of cellular responses to cyclical hypoxia and stretch.
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Affiliation(s)
- Noelia Campillo
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Cellular and Respiratory Biomechanics, Institute for Bioengineering of CataloniaBarcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades RespiratoriasMadrid, Spain
| | - Ignasi Jorba
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Cellular and Respiratory Biomechanics, Institute for Bioengineering of CataloniaBarcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades RespiratoriasMadrid, Spain
| | - Laura Schaedel
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Cellular and Respiratory Biomechanics, Institute for Bioengineering of CataloniaBarcelona, Spain
| | - Blai Casals
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Cellular and Respiratory Biomechanics, Institute for Bioengineering of CataloniaBarcelona, Spain
| | - David Gozal
- Biological Sciences Division, Department of Pediatrics, Pritzker School of Medicine, The University of Chicago Chicago, IL, USA
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades RespiratoriasMadrid, Spain; Institut d'Investigacions Biomèdiques August Pi i SunyerBarcelona, Spain
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades RespiratoriasMadrid, Spain; Institut d'Investigacions Biomèdiques August Pi i SunyerBarcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de BarcelonaBarcelona, Spain; Cellular and Respiratory Biomechanics, Institute for Bioengineering of CataloniaBarcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades RespiratoriasMadrid, Spain
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Intermittent Hypoxia-Induced Cardiovascular Remodeling Is Reversed by Normoxia in a Mouse Model of Sleep Apnea. Chest 2016; 149:1400-8. [DOI: 10.1016/j.chest.2015.11.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 10/02/2015] [Accepted: 11/02/2015] [Indexed: 11/19/2022] Open
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Cardiorespiratory events in preterm infants: interventions and consequences. J Perinatol 2016; 36:251-8. [PMID: 26583943 DOI: 10.1038/jp.2015.165] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 09/29/2015] [Accepted: 10/05/2015] [Indexed: 01/09/2023]
Abstract
Stabilization of respiration and oxygenation continues to be one of the main challenges in clinical care of the neonate. Despite aggressive respiratory support including mechanical ventilation, continuous positive airway pressure, oxygen and caffeine therapy to reduce apnea and accompanying intermittent hypoxemia, the incidence of intermittent hypoxemia events continues to increase during the first few months of life. Even with improvements in clinical care, standards for oxygen saturation targeting and modes of respiratory support have yet to be identified in this vulnerable infant cohort. In addition, we are only beginning to explore the association between the incidence and pattern of cardiorespiratory events during early postnatal life and both short- and long-term morbidity including retinopathy of prematurity, growth, sleep-disordered breathing and neurodevelopmental impairment. Part 1 of this review included a summary of lung development and diagnostic methods of cardiorespiratory monitoring. In Part 2 we focus on clinical interventions and the short- and long-term consequences of cardiorespiratory events in preterm infants.
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Cortese R, Zhang C, Bao R, Andrade J, Khalyfa A, Mokhlesi B, Gozal D. DNA Methylation Profiling of Blood Monocytes in Patients With Obesity Hypoventilation Syndrome: Effect of Positive Airway Pressure Treatment. Chest 2016; 150:91-101. [PMID: 26923628 DOI: 10.1016/j.chest.2016.02.648] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND OSA is a highly prevalent condition that is associated with a wide range of long-term morbidities including metabolic, cardiovascular, and cognitive alterations, possibly via activation of systemic inflammatory and oxidative stress pathways. Implementation of positive airway pressure (PAP) is the first-line treatment for OSA, as well as for obesity hypoventilation syndrome (OHS), its most severe phenotype. However, the molecular and cellular mechanisms underlying OHS-induced morbidities and their response to PAP treatment remain unclear, and could be mediated, in part, by OSA-induced epigenetic changes. METHODS Blood was collected before starting PAP treatment (PRE group), as well as 6 weeks after PAP treatment (POST group) in 15 adult patients with OHS. DNA methylation profiles were studied by methylated DNA immunoprecipitation coupled to microarrays (MeDIP-chip) in six representative patients and further verified in a cohort of 15 patients by MeDIP-quantitative PCR. RESULTS We identified 1,847 regions showing significant differential DNA methylation (P < .001; model-based analysis of tiling arrays score, > 4) between the groups. Analysis of biochemical pathways and gene networks demonstrated that differentially methylated regions were associated with immune responses, and particularly with mechanisms governing gene regulation by peroxisome proliferation-activated receptors (PPARs). Single-locus quantitative PCR analysis revealed that DNA methylation was increased at the PPAR-responsive elements (PPAREs) of eight genes in the post-treatment samples (PRE/POST fold changes: ABCA1, 3.11; ABCG1, 1.72; CD36, 5.04; FABP4, 2.49; HMOX, 2.74; NOS2, 7.78; PEPCK, 9.27; and ADIPOQ, 1.73), suggesting that PAP treatment leads to an increase in DNA methylation at PPAREs, possibly affecting the binding of the PPAR-γ complex and downstream gene expression. CONCLUSIONS Our work provides initial evidence of epigenetic regulation particularly involving metabolic pathways in patients with OHS who are responsive to PAP treatment.
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Affiliation(s)
- Rene Cortese
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, IL
| | - Chunling Zhang
- Center for Research Informatics, University of Chicago, Chicago, IL
| | - Riyue Bao
- Center for Research Informatics, University of Chicago, Chicago, IL
| | - Jorge Andrade
- Center for Research Informatics, University of Chicago, Chicago, IL
| | - Abdelnaby Khalyfa
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, IL
| | - Babak Mokhlesi
- Sleep Disorders Center and Section of Pulmonary and Critical Care Medicine, Department of Medicine, University of Chicago, Chicago, IL
| | - David Gozal
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, University of Chicago, Chicago, IL.
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Almendros I, Gileles-Hillel A, Khalyfa A, Wang Y, Zhang SX, Carreras A, Farré R, Gozal D. Adipose tissue macrophage polarization by intermittent hypoxia in a mouse model of OSA: effect of tumor microenvironment. Cancer Lett 2015; 361:233-9. [PMID: 25779675 DOI: 10.1016/j.canlet.2015.03.010] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 12/26/2022]
Abstract
Intermittent hypoxia (IH)-induces alterations in tumor-associated macrophages (TAMs) that are associated with adverse cancer outcomes, as reported in patients suffering from sleep apnea. Adipose tissues (AT) and bone-marrow (BM)-derived cells are the inferred sources of macrophages infiltrating malignant tumors. Here, the sources of TAMs and the phenotypic changes induced by IH in the ipsilateral and contralateral AT were investigated by using a syngeneic murine solid tumor model (TC1). C57/B6 male mice were exposed to either IH or room air (RA) for 6 weeks, with TC1 cells being inoculated in the 2nd week. Macrophage content, phenotype and tissue origin were assessed in tumors, and ipsilateral and contralateral AT. IH induced a ~2.2-fold increase in TAM tumor infiltration. However, differential responses in the tumor ipsilateral and contralateral AT emerged: IH increased infiltration of preferentially M1 macrophages in contralateral AT, while reductions in macrophages emerged in ipsilateral AT and primarily consisted of the M2 phenotype. These changes were accompanied by reciprocal increases in resident and BM-derived TAMs in the tumor. IH-induced phenotypic alterations in AT macrophages surrounding the tumor and their increased infiltration within the tumor may contribute to the accelerated tumor progression associated with IH.
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Affiliation(s)
- Isaac Almendros
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Alex Gileles-Hillel
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Abdelnaby Khalyfa
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Yang Wang
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Shelley X Zhang
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Alba Carreras
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-IDIBAPS, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain
| | - David Gozal
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL 60637, USA.
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