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Appiah CB, Gardner JJ, Farmer GE, Cunningham RL, Cunningham JT. Chronic intermittent hypoxia-induced hypertension: the impact of sex hormones. Am J Physiol Regul Integr Comp Physiol 2024; 326:R333-R345. [PMID: 38406843 DOI: 10.1152/ajpregu.00258.2023] [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: 11/16/2023] [Revised: 02/12/2024] [Accepted: 02/15/2024] [Indexed: 02/27/2024]
Abstract
Obstructive sleep apnea, a common form of sleep-disordered breathing, is characterized by intermittent cessations of breathing that reduce blood oxygen levels and contribute to the development of hypertension. Hypertension is a major complication of obstructive sleep apnea that elevates the risk of end-organ damage. Premenopausal women have a lower prevalence of obstructive sleep apnea and cardiovascular disease than men and postmenopausal women, suggesting that sex hormones play a role in the pathophysiology of sleep apnea-related hypertension. The lack of protection in men and postmenopausal women implicates estrogen and progesterone as protective agents but testosterone as a permissive agent in sleep apnea-induced hypertension. A better understanding of how sex hormones contribute to the pathophysiology of sleep apnea-induced hypertension is important for future research and possible hormone-based interventions. The effect of sex on the pathophysiology of sleep apnea and associated intermittent hypoxia-induced hypertension is of important consideration in the screening, diagnosis, and treatment of the disease and its cardiovascular complications. This review summarizes our current understanding of the impact of sex hormones on blood pressure regulation in sleep apnea with a focus on sex differences.
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Affiliation(s)
- Cephas B Appiah
- Department of Physiology and Anatomy, School of Biomedical Sciences, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States
| | - Jennifer J Gardner
- Department of Physiology and Anatomy, School of Biomedical Sciences, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States
| | - George E Farmer
- Department of Physiology and Anatomy, School of Biomedical Sciences, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States
| | - Rebecca L Cunningham
- Department of Pharmaceutical Sciences, System College of Pharmacy, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States
| | - J Thomas Cunningham
- Department of Physiology and Anatomy, School of Biomedical Sciences, University of North Texas Health Science Center at Fort Worth, Fort Worth, Texas, United States
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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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Ryou MG, Chen X, Cai M, Wang H, Jung ME, Metzger DB, Mallet RT, Shi X. Intermittent Hypoxia Training Prevents Deficient Learning-Memory Behavior in Mice Modeling Alzheimer's Disease: A Pilot Study. Front Aging Neurosci 2021; 13:674688. [PMID: 34276338 PMCID: PMC8282412 DOI: 10.3389/fnagi.2021.674688] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/27/2021] [Indexed: 11/16/2022] Open
Abstract
In mouse models of Alzheimer's disease (AD), normobaric intermittent hypoxia training (IHT) can preserve neurobehavioral function when applied before deficits develop, but IHT's effectiveness after onset of amyloid-β (Aβ) accumulation is unclear. This study tested the hypothesis that IHT improves learning-memory behavior, diminishes Aβ accumulation in cerebral cortex and hippocampus, and enhances cerebrocortical contents of the neuroprotective trophic factors erythropoietin and brain-derived neurotrophic factor (BDNF) in mice manifesting AD traits. Twelve-month-old female 3xTg-AD mice were assigned to untreated 3xTg-AD (n = 6), AD+IHT (n = 6), and AD+sham-IHT (n = 6) groups; 8 untreated wild-type (WT) mice also were studied. AD+IHT mice alternately breathed 10% O2 for 6 min and room air for 4 min, 10 cycles/day for 21 days; AD+sham-IHT mice breathed room air. Spatial learning-memory was assessed by Morris water maze. Cerebrocortical and hippocampal Aβ40 and Aβ42 contents were determined by ELISA, and cerebrocortical erythropoietin and BDNF were analyzed by immunoblotting and ELISA. The significance of time (12 vs. 12 months + 21 days) and treatment (IHT vs. sham-IHT) was evaluated by two-factor ANOVA. The change in swimming distance to find the water maze platform after 21 d IHT (-1.6 ± 1.8 m) differed from that after sham-IHT (+5.8 ± 2.6 m). Cerebrocortical and hippocampal Aβ42 contents were greater in 3xTg-AD than WT mice, but neither time nor treatment significantly affected Aβ40 or Aβ42 contents in the 3xTg-AD mice. Cerebrocortical erythropoietin and BDNF contents increased appreciably after IHT as compared to untreated 3xTg-AD and AD+sham-IHT mice. In conclusion, moderate, normobaric IHT prevented spatial learning-memory decline and restored cerebrocortical erythropoietin and BDNF contents despite ongoing Aβ accumulation in 3xTg-AD mice.
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Affiliation(s)
- Myoung-Gwi Ryou
- Department of Medical Laboratory Science and Public Health, Tarleton State University, Texas A&M University System, Stephenville, TX, United States
| | - Xiaoan Chen
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
- College of Sports Science, Jishou University, Jishou, China
| | - Ming Cai
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Hong Wang
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai, China
| | - Marianna E. Jung
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Daniel B. Metzger
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Robert T. Mallet
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Xiangrong Shi
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, United States
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Marciante AB, Shell B, Farmer GE, Cunningham JT. Role of angiotensin II in chronic intermittent hypoxia-induced hypertension and cognitive decline. Am J Physiol Regul Integr Comp Physiol 2021; 320:R519-R525. [PMID: 33595364 PMCID: PMC8238144 DOI: 10.1152/ajpregu.00222.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 01/19/2021] [Accepted: 02/13/2021] [Indexed: 02/03/2023]
Abstract
Sleep apnea is characterized by momentary interruptions in normal respiration and leads to periods of decreased oxygen, or intermittent hypoxia. Chronic intermittent hypoxia is a model of the hypoxemia associated with sleep apnea and results in a sustained hypertension that is maintained during normoxia. Adaptations of the carotid body and activation of the renin-angiotensin system may contribute to the development of hypertension associated with chronic intermittent hypoxia. The subsequent activation of the brain renin-angiotensin system may produce changes in sympathetic regulatory neural networks that support the maintenance of the hypertension associated with intermittent hypoxia. Hypertension and sleep apnea not only increase risk for cardiovascular disease but are also risk factors for cognitive decline and Alzheimer's disease. Activation of the angiotensin system could be a common mechanism that links these disorders.
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Affiliation(s)
- Alexandria B Marciante
- Breathing REsearch And THErapeutics (BREATHE) Center, University of Florida, Gainesville, Florida
- Department of Physical Therapy, University of Florida, Gainesville, Florida
- McKnight Brain Institute, University of Florida, Gainesville, Florida
| | - Brent Shell
- Zuckerberg College of Health Sciences, University of Massachusetts-Lowell, Lowell, Massachusetts
- Department of Biomedical and Nutritional Sciences, University of Massachusetts-Lowell, Lowell, Massachusetts
| | - George E Farmer
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - J Thomas Cunningham
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
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Mele C, Caputo M, Bisceglia A, Samà MT, Zavattaro M, Aimaretti G, Pagano L, Prodam F, Marzullo P. Immunomodulatory Effects of Vitamin D in Thyroid Diseases. Nutrients 2020; 12:nu12051444. [PMID: 32429416 PMCID: PMC7284826 DOI: 10.3390/nu12051444] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 12/24/2022] Open
Abstract
Vitamin D is a secosteroid with a pleiotropic role in multiple physiological processes. Besides the well-known activity on bone homeostasis, recent studies suggested a peculiar role of vitamin D in different non-skeletal pathways, including a key role in the modulation of immune responses. Recent evidences demonstrated that vitamin D acts on innate and adaptative immunity and seems to exert an immunomodulating action on autoimmune diseases and cancers. Several studies demonstrated a relationship between vitamin D deficiency, autoimmune thyroid disorders, and thyroid cancer. This review aims to summarize the evidences on the immunomodulatory effect of vitamin D on thyroid diseases.
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Affiliation(s)
- Chiara Mele
- Department of Translational Medicine, University of Piemonte Orientale UPO, 28100 Novara, Italy; (C.M.); (G.A.)
- Division of General Medicine, S. Giuseppe Hospital, I.R.C.C.S. Istituto Auxologico Italiano, 28824 Verbania, Italy
| | - Marina Caputo
- Department of Health Sciences, University of Piemonte Orientale UPO, 28100 Novara, Italy; (M.C.); (F.P.)
- Division of Endocrinology, University Hospital “Maggiore della Carità”, 28100 Novara, Italy; (M.T.S.); (M.Z.)
| | - Alessandro Bisceglia
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (A.B.); (L.P.)
| | - Maria Teresa Samà
- Division of Endocrinology, University Hospital “Maggiore della Carità”, 28100 Novara, Italy; (M.T.S.); (M.Z.)
| | - Marco Zavattaro
- Division of Endocrinology, University Hospital “Maggiore della Carità”, 28100 Novara, Italy; (M.T.S.); (M.Z.)
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (A.B.); (L.P.)
| | - Gianluca Aimaretti
- Department of Translational Medicine, University of Piemonte Orientale UPO, 28100 Novara, Italy; (C.M.); (G.A.)
- Division of Endocrinology, University Hospital “Maggiore della Carità”, 28100 Novara, Italy; (M.T.S.); (M.Z.)
| | - Loredana Pagano
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, 10126 Turin, Italy; (A.B.); (L.P.)
| | - Flavia Prodam
- Department of Health Sciences, University of Piemonte Orientale UPO, 28100 Novara, Italy; (M.C.); (F.P.)
- Division of Endocrinology, University Hospital “Maggiore della Carità”, 28100 Novara, Italy; (M.T.S.); (M.Z.)
| | - Paolo Marzullo
- Department of Translational Medicine, University of Piemonte Orientale UPO, 28100 Novara, Italy; (C.M.); (G.A.)
- Division of General Medicine, S. Giuseppe Hospital, I.R.C.C.S. Istituto Auxologico Italiano, 28824 Verbania, Italy
- Correspondence: ; Tel.: +39-03-2351-4436
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Bellan M, Andreoli L, Mele C, Sainaghi PP, Rigamonti C, Piantoni S, De Benedittis C, Aimaretti G, Pirisi M, Marzullo P. Pathophysiological Role and Therapeutic Implications of Vitamin D in Autoimmunity: Focus on Chronic Autoimmune Diseases. Nutrients 2020; 12:E789. [PMID: 32192175 PMCID: PMC7146294 DOI: 10.3390/nu12030789] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 03/13/2020] [Indexed: 02/07/2023] Open
Abstract
Vitamin D is a pleiotropic secosteroid yielding multiple actions in human physiology. Besides the canonical regulatory activity on bone metabolism, several non-classical actions have been described and the ability of vitamin D to partake in the regulation of the immune system is particularly interesting, though far stronger and convincing evidence has been collected in in vitro as compared to in vivo studies. Whether vitamin D is able to regulate at physiological concentrations the human immune system remains unproven to date. Consequently, it is not established if vitamin D status is a factor involved in the pathogenesis of immune-mediated diseases and if cholecalciferol supplementation acts as an adjuvant for autoimmune diseases. The development of autoimmunity is a heterogeneous process, which may involve different organs and systems with a wide range of clinical implications. In the present paper, we reviewed the current evidences regarding vitamin D role in the pathogenesis and management of different autoimmune diseases.
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Affiliation(s)
- Mattia Bellan
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of Internal Medicine, “AOU Maggiore della Carità”, 28100 Novara, Italy
- CAAD, Centre for Autoimmune and Allergic Diseases, 28100 Novara, Italy
| | - Laura Andreoli
- Rheumatology and Clinical Immunology Unit and Department of Clinical and Experimental Sciences, Spedali Civili and University of Brescia, 25128 Brescia, Italy; (L.A.); (S.P.)
| | - Chiara Mele
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
| | - Pier Paolo Sainaghi
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of Internal Medicine, “AOU Maggiore della Carità”, 28100 Novara, Italy
- CAAD, Centre for Autoimmune and Allergic Diseases, 28100 Novara, Italy
| | - Cristina Rigamonti
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of Internal Medicine, “AOU Maggiore della Carità”, 28100 Novara, Italy
- CAAD, Centre for Autoimmune and Allergic Diseases, 28100 Novara, Italy
| | - Silvia Piantoni
- Rheumatology and Clinical Immunology Unit and Department of Clinical and Experimental Sciences, Spedali Civili and University of Brescia, 25128 Brescia, Italy; (L.A.); (S.P.)
| | - Carla De Benedittis
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of Internal Medicine, “AOU Maggiore della Carità”, 28100 Novara, Italy
- CAAD, Centre for Autoimmune and Allergic Diseases, 28100 Novara, Italy
| | - Gianluca Aimaretti
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
| | - Mario Pirisi
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of Internal Medicine, “AOU Maggiore della Carità”, 28100 Novara, Italy
- CAAD, Centre for Autoimmune and Allergic Diseases, 28100 Novara, Italy
| | - Paolo Marzullo
- Department of Translational Medicine, Università del Piemonte Orientale UPO, 28100 Novara, Italy; (M.B.); (C.M.); (P.P.S.); (C.R.); (C.D.B.); (G.A.); (M.P.)
- Division of General Medicine, Ospedale S. Giuseppe, I.R.C.C.S. Istituto Auxologico Italiano, 28921 Verbania, Italy
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Wang H, Shi X, Schenck H, Hall JR, Ross SE, Kline GP, Chen S, Mallet RT, Chen P. Intermittent Hypoxia Training for Treating Mild Cognitive Impairment: A Pilot Study. Am J Alzheimers Dis Other Demen 2020; 35:1533317519896725. [PMID: 31902230 PMCID: PMC10624018 DOI: 10.1177/1533317519896725] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Although intermittent hypoxia training (IHT) has proven effective against various clinical disorders, its impact on mild cognitive impairment (MCI) is unknown. This pilot study examined IHT's safety and therapeutic efficacy in elderly patients with amnestic MCI (aMCI). Seven patients with aMCI (age 69 ± 3 years) alternately breathed 10% O2 and room-air, each 5 minutes, for 8 cycles/session, 3 sessions/wk for 8 weeks. The patients' resting arterial pressures fell by 5 to 7 mm Hg (P < .05) and cerebral tissue oxygenation increased (P < .05) following IHT. Intermittent hypoxia training enhanced hypoxemia-induced cerebral vasodilation (P < .05) and improved mini-mental state examination and digit span scores from 25.7 ± 0.4 to 27.7 ± 0.6 (P = .038) and from 24.7 ± 1.2 to 26.1 ± 1.3 (P = .047), respectively. California verbal learning test score tended to increase (P = .102), but trail making test-B and controlled oral word association test scores were unchanged. Adaptation to moderate IHT may enhance cerebral oxygenation and hypoxia-induced cerebrovasodilation while improving short-term memory and attention in elderly patients with aMCI.
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Affiliation(s)
- Hong Wang
- Departments of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
- Shanghai University of Medicine & Health Sciences, Shanghai, China
| | - Xiangrong Shi
- Departments of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
- Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Hannah Schenck
- Departments of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - James R. Hall
- Departments of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX, USA
- Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Sarah E. Ross
- Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
- Department of Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Geoffrey P. Kline
- Department of Internal Medicine, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Shande Chen
- Institute for Healthy Aging, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Robert T. Mallet
- Departments of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Peijie Chen
- Shanghai University of Sport, Shanghai, China
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Buendia JR, Li Y, Hu FB, Cabral HJ, Bradlee ML, Quatromoni PA, Singer MR, Curhan GC, Moore LL. Long-term yogurt consumption and risk of incident hypertension in adults. J Hypertens 2019; 36:1671-1679. [PMID: 29952852 DOI: 10.1097/hjh.0000000000001737] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To evaluate the relation between yogurt consumption as well as cheese, milk, and total dairy, and high blood pressure (HBP) in two Nurses' Health Study cohorts (NHS, n = 69 298), NHS II (n = 84 368) and the Health Professionals Follow-Up Study (HPFS, n = 30 512). METHODS NHS, NHS II, and HPFS participants were followed for incident HBP for up to 30, 20, and 24 years, respectively. Hazard ratios were calculated using time-dependent multivariate-adjusted Cox proportional hazards models. Pooled risk estimates were derived from fixed effects meta-analyses. RESULTS Participants consuming at least five servings per week (vs. <1 serving per month) of yogurt in NHS, NHS II, and HPFS had 19% (95% CI 0.75-0.87), 17% (95% CI 0.77-0.90), and 6% (95% CI 0.83-1.07) lower HBP risks, respectively. In pooled analyses of these cohorts, higher yogurt consumption was linked with 16% (95% CI 0.80-0.88) lower HBP risk; higher total dairy (3 to <6 vs. <0.5 servings/day), milk (2 to <6/day vs. <4/week) and cheese (1 to 4/day vs. <1/week) were associated with 16% (95% CI 0.81-0.87), 12% (95% CI 0.86-0.90), and 6% (95% CI 0.90-0.97) lower HBP risks, respectively. After controlling for BMI as a possible causal intermediate, total dairy, yogurt, milk, and cheese were associated with 13, 10, 8, and 8% lower HBP risks, respectively. The combination of higher yogurt intake and higher DASH ('Dietary Approaches to Stop Hypertension') diet scores was associated with 30% (95% CI 0.66-0.75) lower HBP risk compared with lower levels of both factors. CONCLUSION Higher total dairy intake, especially in the form of yogurt, was associated with lower risk of incident HBP in middle-aged and older adult men and women.
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Affiliation(s)
- Justin R Buendia
- Department of Medicine/Preventive Medicine and Epidemiology, Boston University School of Medicine
| | - Yanping Li
- Department of Nutrition, Harvard T. H. Chan School of Public Health
| | - Frank B Hu
- Department of Nutrition, Harvard T. H. Chan School of Public Health
| | - Howard J Cabral
- Department of Biostatistics, Boston University School of Public Health
| | - M Loring Bradlee
- Department of Medicine/Preventive Medicine and Epidemiology, Boston University School of Medicine
| | - Paula A Quatromoni
- Department of Health Sciences/Programs in Nutrition, Sargent College of Health and Rehabilitation Sciences, Boston University
| | - Martha R Singer
- Department of Medicine/Preventive Medicine and Epidemiology, Boston University School of Medicine
| | - Gary C Curhan
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Lynn L Moore
- Department of Medicine/Preventive Medicine and Epidemiology, Boston University School of Medicine
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AlMarabeh S, Abdulla MH, O'Halloran KD. Is Aberrant Reno-Renal Reflex Control of Blood Pressure a Contributor to Chronic Intermittent Hypoxia-Induced Hypertension? Front Physiol 2019; 10:465. [PMID: 31105584 PMCID: PMC6491928 DOI: 10.3389/fphys.2019.00465] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 04/04/2019] [Indexed: 12/16/2022] Open
Abstract
Renal sensory nerves are important in the regulation of body fluid and electrolyte homeostasis, and blood pressure. Activation of renal mechanoreceptor afferents triggers a negative feedback reno-renal reflex that leads to the inhibition of sympathetic nervous outflow. Conversely, activation of renal chemoreceptor afferents elicits reflex sympathoexcitation. Dysregulation of reno-renal reflexes by suppression of the inhibitory reflex and/or activation of the excitatory reflex impairs blood pressure control, predisposing to hypertension. Obstructive sleep apnoea syndrome (OSAS) is causally related to hypertension. Renal denervation in patients with OSAS or in experimental models of chronic intermittent hypoxia (CIH), a cardinal feature of OSAS due to recurrent apnoeas (pauses in breathing), results in a decrease in circulating norepinephrine levels and attenuation of hypertension. The mechanism of the beneficial effect of renal denervation on blood pressure control in models of CIH and OSAS is not fully understood, since renal denervation interrupts renal afferent signaling to the brain and sympathetic efferent signals to the kidneys. Herein, we consider the currently proposed mechanisms involved in the development of hypertension in CIH disease models with a focus on oxidative and inflammatory mediators in the kidneys and their potential influence on renal afferent control of blood pressure, with wider consideration of the evidence available from a variety of hypertension models. We draw focus to the potential contribution of aberrant renal afferent signaling in the development, maintenance and progression of high blood pressure, which may have relevance to CIH-induced hypertension.
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Affiliation(s)
- Sara AlMarabeh
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Mohammed H Abdulla
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork, Cork, Ireland
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Abuyassin B, Badran M, Ayas NT, Laher I. The antioxidant α-lipoic acid attenuates intermittent hypoxia-related renal injury in a mouse model of sleep apnea. Sleep 2019; 42:5382296. [DOI: 10.1093/sleep/zsz066] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 03/08/2019] [Indexed: 12/25/2022] Open
Affiliation(s)
- Bisher Abuyassin
- Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mohammad Badran
- Departments of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Najib T Ayas
- Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ismail Laher
- Departments of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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Ribon-Demars A, Pialoux V, Boreau A, Marcouiller F, Larivière R, Bairam A, Joseph V. Protective roles of estradiol against vascular oxidative stress in ovariectomized female rats exposed to normoxia or intermittent hypoxia. Acta Physiol (Oxf) 2019; 225:e13159. [PMID: 29947475 DOI: 10.1111/apha.13159] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/11/2018] [Accepted: 06/21/2018] [Indexed: 01/06/2023]
Abstract
AIM We tested the hypothesis that estradiol (E2 ) reduces aortic oxidative stress and endothelial dysfunction in ovariectomized (OVX) female rats exposed to room air (RA) or chronic intermittent hypoxia (CIH). METHODS We used intact or OVX female rats treated with vehicle or E2 (0.5 mg/kg/d) and exposed to RA or CIH (21%-10% O2 , 10 cycles/h, 8 h/d) for 7 or 35 days, and measured the arterial pressure, heart rate and plasma endothelin-1 levels. We also measured in thoracic aortic samples, the activities of the pro-oxidant enzymes NADPH (NOX) and xanthine oxidase (XO), the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase and the advanced oxidation protein products (AOPP-oxidative stress marker). Finally, we used aortic rings to assess the contractile response to phenylephrine and the vasodilatory response to acetylcholine. RESULTS After 7 or 35 days of CIH, E2 supplementation reduced arterial pressure. E2 reduced plasma endothelin-1 levels after 7 days of CIH, but not after 35 days. Ovariectomy, but not CIH for 7 days, increased aortic oxidative stress and E2 treatment prevented this effect. Remarkably, in animals exposed to RA, this was achieved by a reduction in NOX and XO activities, but in animals exposed to CIH this was achieved by increased catalase activity. In OVX female rats exposed to CIH for 7 days, E2 supplementation improved the NO-mediated vasodilation. After 35 days of CIH, enzymatic activities, AOPP and aortic reactivity were similar in all groups. CONCLUSION E2 -based therapy could help prevent the vascular consequences of CIH in apneic women.
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Affiliation(s)
- Alexandra Ribon-Demars
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec; Université Laval; Québec QC Canada
- Laboratoire Inter-Universitaire de biologie de la motricité; Université Claude Bernard Lyon1; Villeurbanne France
| | - Vincent Pialoux
- Laboratoire Inter-Universitaire de biologie de la motricité; Université Claude Bernard Lyon1; Villeurbanne France
- Institut Universitaire de France; Paris France
| | - Anaëlle Boreau
- Laboratoire Inter-Universitaire de biologie de la motricité; Université Claude Bernard Lyon1; Villeurbanne France
| | - François Marcouiller
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec; Université Laval; Québec QC Canada
| | - Richard Larivière
- Centre de Recherche du Centre Hospitalier; Universitaire de Québec; Hôtel-Dieu de Québec; Université Laval; Québec QC Canada
| | - Aida Bairam
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec; Université Laval; Québec QC Canada
| | - Vincent Joseph
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec; Université Laval; Québec QC Canada
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12
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O'Neill J, Jasionek G, Drummond SE, Brett O, Lucking EF, Abdulla MA, O'Halloran KD. Renal cortical oxygen tension is decreased following exposure to long-term but not short-term intermittent hypoxia in the rat. Am J Physiol Renal Physiol 2019; 316:F635-F645. [PMID: 30648908 DOI: 10.1152/ajprenal.00254.2018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chronic kidney disease (CKD) occurs in more than 50% of patients with obstructive sleep apnea (OSA). However, the impact of intermittent hypoxia (IH) on renal function and oxygen homeostasis is unclear. Male Sprague-Dawley rats were exposed to IH (270 s at 21% O2; 90 s hypoxia, 6.5% O2 at nadir) for 4 h [acute IH (AIH)] or to chronic IH (CIH) for 8 h/day for 2 wk. Animals were anesthetized and surgically prepared for the measurement of mean arterial pressure (MAP), and left renal excretory function, renal blood flow (RBF), and renal oxygen tension (Po2). AIH had no effect on MAP (123 ± 14 vs. 129 ± 14 mmHg, means ± SE, sham vs. IH). The CIH group was hypertensive (122 ± 9 vs. 144 ± 15 mmHg, P < 0.05). Glomerular filtration rate (GFR) (0.92 ± 0.27 vs. 1.33 ± 0.33 ml/min), RBF (3.8 ± 1.5 vs. 7.2 ± 2.4 ml/min), and transported sodium (TNa) (132 ± 39 vs. 201 ± 47 μmol/min) were increased in the AIH group (all P < 0.05). In the CIH group, GFR (1.25 ± 0.28 vs. 0.86 ± 0.28 ml/min, P < 0.05) and TNa (160 ± 39 vs. 120 ± 40 μmol/min, P < 0.05) were decreased, while RBF (4.13 ± 1.5 vs. 3.08 ± 1.5 ml/min) was not significantly different. Oxygen consumption (QO2) was increased in the AIH group (6.76 ± 2.60 vs. 13.60 ± 7.77 μmol/min, P < 0.05), but it was not significantly altered in the CIH group (3.97 ± 2.63 vs. 6.82 ± 3.29 μmol/min). Cortical Po2 was not significantly different in the AIH group (46 ± 4 vs. 46 ± 3 mmHg), but it was decreased in the CIH group (44 ± 5 mmHg vs. 38 ± 2 mmHg, P < 0.05). For AIH, renal oxygen homeostasis was preserved through a maintained balance between O2 supply (RBF) and consumption (GFR). For CIH, mismatched TNa and QO2 reflect inefficient O2 utilization and, thereby, sustained decrease in cortical Po2.
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Affiliation(s)
- Julie O'Neill
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Greg Jasionek
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Sarah E Drummond
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Orla Brett
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Eric F Lucking
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Mohammed A Abdulla
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine and Health, University College Cork , Cork , Ireland
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13
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Bellan M, Marzullo P. New Insights on Low Vitamin D Plasma Concentration as a Potential Cardiovascular Risk Factor. Open Rheumatol J 2018. [DOI: 10.2174/1874312901812010261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The role of Vitamin D hormone in human health and disease is still debated. Recently, growing attention has been paid to its putative role in cardiovascular system homeostasis with several studies that suggested a correlation between low vitamin D levels and increased cardiovascular risk. Several mechanisms are involved in the development of cardiovascular diseases: systemic inflammation, endothelial dysfunction, arterial hypertension and insulin resistance. In the present paper, we have revised the current literature supporting a role for vitamin D in the development of these pathogenetic processes. Finally, we have evaluated the current evidence linking vitamin D to atherosclerosis and its natural consequence, cardiovascular diseases.
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14
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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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15
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Adaptation to Hypoxia in Sleep Apnea Patients: Multifaceted Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018. [PMID: 30357711 DOI: 10.1007/5584_2018_268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Obstructive sleep apnea syndrome (OSA) is a form of sleep disordered breathing. The key phenomena are multiple repetitive pauses or restriction of airflow in the airway, defined as apnea and hypopnea. This study was based on a retrospective analysis of the results of polysomnographic (PSG) recordings of 230 adult patients (62 women and 168 men), being evaluated for OSA. The mean age, body mass index (BMI), apnea-hypopnea index (AHI), and pulse oximetry (SO2 nadir) of all patients were 50.4 ± 12.7 years, 30.4 ± 5.4 kg/m2, 33.6 ± 26.6 1/h, and 80.7 ± 12.1%, respectively. Statistical analysis was performed taking into account the moment of obstructive apnea occurrence and duration, sleep stage, and the SaO2 nadir associated with these events. We found a lengthening of apneic episodes with progressing of sleep-time, which depended on the sleep-time. There was rather a fast increase in apnea duration in the first quartile of sleep-time. In the later sleep phases, the dynamics of the increase were four-fold weaker. The lengthening of apnea duration was dependent on the severity of AHI, but was hardly related to the sleep stage or arterial desaturation. In conclusion, the results revealed two time scales of a lengthening of apneic episodes as a function of sleep-time in OSA patients. Sympathetic activation and spleen reflex may be involved in the observed phenomenon. Although the exact mechanisms of increasing duration of apneic episodes with the passage of sleep remain elusive, we believe these mechanisms are liable to be multifaceted.
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16
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Rosenblum WI. Endothelium-dependent responses in the microcirculation observed in vivo. Acta Physiol (Oxf) 2018; 224:e13111. [PMID: 29873936 DOI: 10.1111/apha.13111] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/19/2018] [Accepted: 06/04/2018] [Indexed: 12/17/2022]
Abstract
Endothelium-dependent responses were first demonstrated 40 years ago in the aorta. Since then, extensive research has been conducted in vitro using conductance vessels and materials derived from them. However, the microcirculation controls blood flow to vital organs and has been the focus of in vivo studies of endothelium-dependent dilation beginning immediately after the first in vitro report. Initial in vivo studies employed a light/dye technique for selectively damaging the endothelium to unequivocally prove, in vivo, the existence of endothelium-dependent dilation and in the microvasculature. Endothelium-dependent constriction was similarly proven. Endothelium-dependent agonists include acetylcholine (ACh), bradykinin, arachidonic acid, calcium ionophore A-23187, calcitonin gene-related peptide (CGRP), serotonin, histamine and endothelin-1. Normal and disease states have been studied. Endothelial nitric oxide synthase, cyclooxygenase and cytochrome P450 have been shown to generate the mediators of the responses. Some of the key enzyme systems generate reactive oxygen species (ROS) like superoxide which may prevent EDR. However, one ROS, namely H2 O2 , is one of a number of hyperpolarizing factors that cause dilation initiated by endothelium. Depending upon microvascular bed, a single agonist may use different pathways to elicit an endothelium-dependent response. Interpretation of studies using inhibitors of eNOS is complicated by the fact that these inhibitors may also inhibit ATP-sensitive potassium channels. Other in vivo observations of brain arterioles failed to establish nitric oxide as the mediator of responses elicited by CGRP or by ACh and suggest that a nitrosothiol may be a better fit for the latter.
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Affiliation(s)
- W. I. Rosenblum
- Department of Pathology; Icahn School of Medicine at Mt Sinai NYC; New York NY USA
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17
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Krause BJ, Casanello P, Dias AC, Arias P, Velarde V, Arenas GA, Preite MD, Iturriaga R. Chronic Intermittent Hypoxia-Induced Vascular Dysfunction in Rats is Reverted by N-Acetylcysteine Supplementation and Arginase Inhibition. Front Physiol 2018; 9:901. [PMID: 30087615 PMCID: PMC6066978 DOI: 10.3389/fphys.2018.00901] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 06/21/2018] [Indexed: 01/07/2023] Open
Abstract
Chronic intermittent hypoxia (CIH), the main attribute of obstructive sleep apnea (OSA), produces oxidative stress, endothelial dysfunction, and hypertension. Nitric oxide (NO) plays a critical role in controlling the vasomotor tone. The NO level depends on the L-arginine level, which can be reduced by arginase enzymatic activity, and its reaction with the superoxide radical to produce peroxynitrite. Accordingly, we hypothesized whether a combination of an arginase inhibitor and an antioxidant may restore the endothelial function and reduced arterial blood pressure (BP) in CIH-induced hypertensive rats. Male Sprague-Dawley rats 200 g were exposed either to CIH (5% O2, 12 times/h 8 h/day) or sham condition for 35 days. BP was continuously measured by radio-telemetry in conscious animals. After 14 days, rats were treated with 2(S)-amino-6-boronohexanoic acid (ABH 400 μg/kg day, osmotic pump), N-acetylcysteine (NAC 100 mg/kg day, drinking water), or the combination of both drugs until day 35. At the end of the experiments, external carotid and femoral arteries were isolated to determine vasoactive contractile responses induced by KCL and acetylcholine (ACh) with wire-myography. CIH-induced hypertension (~8 mmHg) was reverted by ABH, NAC, and ABH/NAC administration. Carotid arteries from CIH-treated rats showed higher contraction induced by KCl (3.4 ± 0.4 vs. 2.4 ± 0.2 N/m2) and diminished vasorelaxation elicits by ACh compared to sham rats (12.8 ± 1.5 vs. 30.5 ± 4.6%). ABH reverted the increased contraction (2.5 ± 0.2 N/m2) and the reduced vasorelaxation induced by ACh in carotid arteries from CIH-rats (38.1 ± 4.9%). However, NAC failed to revert the enhanced vasocontraction (3.9 ± 0.6 N/m2) induced by KCl and the diminished ACh-induced vasorelaxation in carotid arteries (10.7 ± 0.8%). Femoral arteries from CIH rats showed an increased contractile response, an effect partially reverted by ABH, but completely reverted by NAC and ABH/NAC. The impaired endothelial-dependent relaxation in femoral arteries from CIH rats was reverted by ABH and ABH/NAC. In addition, ABH/NAC at high doses had no effect on liver and kidney gross morphology and biochemical parameters. Thus, although ABH, and NAC alone and the combination of ABH/NAC were able to normalize the elevated BP, only the combined treatment of ABH/NAC normalized the vascular reactivity and the systemic oxidative stress in CIH-treated rats.
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Affiliation(s)
- Bernardo J Krause
- Division of Pediatrics, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paola Casanello
- Division of Pediatrics, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.,Division of Obstetrics & Gynecology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ana C Dias
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paulina Arias
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Victoria Velarde
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - German A Arenas
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcelo D Preite
- Departamento de Química Orgánica, Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo Iturriaga
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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18
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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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19
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Li X, Cai W, Zhang P, Fang K, Zhu J, Shu C. Comparison of Stanford B Aortic Dissection Patients Who Received Thoracic Endovascular Aortic Repair Combined with or without Sleep Apnea Syndrome. Ann Vasc Surg 2018; 52:79-84. [PMID: 29783029 DOI: 10.1016/j.avsg.2018.03.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 02/01/2018] [Accepted: 03/12/2018] [Indexed: 10/16/2022]
Abstract
BACKGROUND Patients with Stanford B aortic dissection (AD) are usually found to have sleep apnea syndrome (SAS). This condition always complicates the patients' respiration. In this study, we collected and analyzed data of patients' perioperative managements during thoracic endovascular aortic repair (TEVAR) for treating patients with Stanford B AD and SAS. Comparison has been made between the patients with SAS and those without SAS. METHODS Between June 2013 and June 2014, the clinical data and outcomes of the Stanford B AD patients in the Department of Vascular Surgery in the Second Xiangya Hospital were retrospectively reviewed and studied. According to the result of polysomnography obtained by using a portable polysomnography monitor (Nox T3, Nox Medical Co. Iceland) in TEVAR candidates, patients have been stratified into SAS-positive and SAS-negative group. Comparison of various variables has been made between these 2 groups. RESULTS One hundred thirty-four patients, with Stanford B AD and treated by TEVAR in our center, were enrolled in this study. Patients' mean age was 52.46 ± 10.84 years. Gender ratio is 114:20, including male 85.07% (114/134) and female 14.93% (20/134). TEVAR was performed in 71.64% (96/134) patients under general anesthesia and 38 patients under local anesthesia. The mean body mass index (BMI) was 23.5 ± 4.2, and the longest follow-up time was 46 months. The patients were stratified into SAS-positive group (n = 23) and SAS-negative group (n = 111). Compared with the patients in the SAS-negative group, those in the SAS-positive group were younger (54.36 ± 0.97 vs. 43.3 ± 1.84 P < 0.0001) but had higher BMI (25.48 ± 0.71 vs. 22.24 ± 0.23, P < 0.0001), with longer hospitalization time (25.52 ± 0.59 vs. 15.68 ± 0.27; P < 0.0001) and without significant differences in the intensive care unit (ICU) stay time (54.87 ± 12.57 vs. 40.27 ± 8.10; P = 0.3369). Furthermore, the complication rate of pulmonary infection (65.22% vs. 13.51%; P < 0.0001), respiratory failure (26.09% vs. 1.80%; P = 0.003), heart failure (26.09% vs. 3.60%; P = 0.0018), and renal failure (30.43% vs. 5.40%; P = 0.0016) are significantly different between SAS-positive and SAS-negative groups. According to the 46-month follow-up, the survival rate of the 2 groups had no significant differences (P = 0.0846). The SAS-negative group result showed that the survival time had no significant correlation with all the factors we explored, whereas the SAS-positive group result showed that the survival time is significantly correlated only with pulmonary infection/failure (r = 0.2798, 95% confidence interval 0.08741 to 0.452, P = 0.0038). CONCLUSIONS Stanford B AD patients who had SAS are likely to have higher BMI. After treating with TEVAR, they usually have longer hospitalization and ICU stay time, as well as higher complication rate. However, there are no significant differences of the survival rate in midtime follow-up. The respiratory system evaluation should be considered carefully in those patients who have diagnosed as having SAS before and after TEVAR because those patients' survival situation may have correlation with their respiratory condition.
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Affiliation(s)
- Xin Li
- Vascular Surgery Department, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Wenwu Cai
- Vascular Surgery Department, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ping Zhang
- Respiratory Department, The Third Hospital of Changsha City, Changsha, Hunan, China
| | - Kun Fang
- Vascular Surgery Center, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Jieting Zhu
- Vascular Surgery Department, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Chang Shu
- Vascular Surgery Department, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China; Vascular Surgery Center, National Center for Cardiovascular Diseases, Fuwai Hospital, Chinese Academy of Medical Sciences, Beijing, China.
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20
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Li JR, Zhao YS, Chang Y, Yang SC, Guo YJ, Ji ES. Fasudil improves endothelial dysfunction in rats exposed to chronic intermittent hypoxia through RhoA/ROCK/NFATc3 pathway. PLoS One 2018; 13:e0195604. [PMID: 29641598 PMCID: PMC5895022 DOI: 10.1371/journal.pone.0195604] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/26/2018] [Indexed: 12/21/2022] Open
Abstract
Endothelial dysfunction is one of the main pathological changes in Obstructive sleep apnoea (OSA). The Rho kinase (ROCK) pathway is associated with endothelial dysfunction. However, the interaction between ROCK and nuclear factor of activated T cells isoform c3 (NFATc3) in the development of this pathological response under chronic intermittent hypoxia (CIH) is unclear. To simulate the OSA model, we established a moderate CIH rat model by administering the fraction of inspired O2 (FiO2) from 21% to 9%, 20 times/h, 8 h/day for 3 weeks. Fasudil (ROCK inhibitor, 8 mg/kg/d, i.p.) was administrated in the rats exposed to CIH for 3 weeks. Our results demonstrated that CIH caused significantly endothelial dysfunction, accompanying with increased ET-1 level, decreased eNOS expression and NO production, which reduced ACh-induced vascular relaxation responses. Moreover, RhoA/ROCK-2/NFATc3 expressions were up-regulated. Fasudil significantly improved CIH induced endothelial dysfunction. Data suggested that the ROCK activation is necessary for endothelial dysfunction during CIH.
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Affiliation(s)
- Jie-Ru Li
- Department of Physiology, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
| | - Ya-Shuo Zhao
- Scientific Research Center, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
| | - Yue Chang
- Department of Physiology, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
| | - Sheng-Chang Yang
- Department of Physiology, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
| | - Ya-Jing Guo
- Scientific Research Center, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
| | - En-Sheng Ji
- Department of Physiology, Hebei University of Chinese Medicine, Shijiazhuang, Hebei, P.R. China
- * E-mail:
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Gautier-Veyret E, Pépin JL, Stanke-Labesque F. Which place of pharmacological approaches beyond continuous positive airway pressure to treat vascular disease related to obstructive sleep apnea? Pharmacol Ther 2017; 186:45-59. [PMID: 29277633 DOI: 10.1016/j.pharmthera.2017.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Obstructive sleep apnea (OSA) is characterized by recurrent episodes of partial or complete upper airway obstruction, occurring during sleep, leading to chronic intermittent hypoxia (IH), which harms the cardiovascular system. OSA is associated with both functional and structural vascular alterations that contribute to an increased prevalence of fatal and non-fatal cardiovascular events. OSA is a heterogeneous disease with respect to the severity of hypoxia, the presence of daytime symptoms, obesity, and cardiovascular comorbidities. Various clusters of OSA phenotypes have been described leading to more highly personalized treatment. The aim of this review is to describe the various therapeutic strategies including continuous positive airway pressure (CPAP), oral appliances, surgery, weight loss, and especially pharmacological interventions that have been evaluated to reduce vascular alterations in both OSA patients and preclinical animal models. Conventional therapies, predominantly CPAP, have a limited impact on vascular alterations in the presence of co-morbidities. A better knowledge of pharmacological therapies targeting IH-induced vascular alterations will facilitate the use of combined therapies and is crucial for designing clinical trials in well-defined OSA phenotypes.
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Affiliation(s)
- Elodie Gautier-Veyret
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France.
| | - Jean-Louis Pépin
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France
| | - Françoise Stanke-Labesque
- Univ. Grenoble Alpes, HP2, F-38041 Grenoble, France; INSERM U1042, 38041 Grenoble, France; Centre hospitalier Universitaire Grenoble Alpes, 38043 Grenoble, France
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22
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Beaudin AE, Waltz X, Hanly PJ, Poulin MJ. Impact of obstructive sleep apnoea and intermittent hypoxia on cardiovascular and cerebrovascular regulation. Exp Physiol 2017; 102:743-763. [PMID: 28439921 DOI: 10.1113/ep086051] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 04/19/2017] [Indexed: 01/06/2023]
Abstract
NEW FINDINGS What is the topic of this review? This review examines the notion that obstructive sleep apnoea (OSA) and intermittent hypoxia (IH) have hormetic effects on vascular health. What advances does it highlight? Clinical (OSA patient) and experimental animal and human models report that IH is detrimental to vascular regulation. However, mild IH and, by extension, mild OSA also have physiological and clinical benefits. This review highlights clinical and experimental animal and human data linking OSA and IH to vascular disease and discusses how hormetic effects of OSA and IH relate to OSA severity, IH intensity and duration, and patient/subject age. Obstructive sleep apnoea (OSA) is associated with increased risk of cardiovascular and cerebrovascular disease, a consequence attributed in part to chronic intermittent hypoxia (IH) resulting from repetitive apnoeas during sleep. Although findings from experimental animal, and human, models have shown that IH is detrimental to vascular regulation, the severity of IH used in many of these animal studies [e.g. inspired fraction of oxygen (FI,O2) = 2-3%; oxygen desaturation index = 120 events h-1 ] is considerably greater than that observed in the majority of patients with OSA. This may also explain disparities between animal and recently developed human models of IH, where IH severity is, by necessity, less severe (e.g. FI,O2 = 10-12%; oxygen desaturation index = 15-30 events h-1 ). In this review, we highlight the current knowledge regarding the impact of OSA and IH on cardiovascular and cerebrovascular regulation. In addition, we critically discuss the recent notion that OSA and IH may have hormetic effects on vascular health depending on conditions such as OSA severity, IH intensity and duration, and age. In general, data support an independent causal link between OSA and vascular disease, particularly for patients with severe OSA. However, the data are equivocal for older OSA patients and patients with mild OSA, because advanced age and short-duration, low-intensity IH have been reported to provide a degree of protection against IH and ischaemic events such as myocardial infarction and stroke, respectively. Overall, additional studies are needed to investigate the beneficial/detrimental effects of mild OSA on the various vascular beds.
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Affiliation(s)
- Andrew E Beaudin
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Xavier Waltz
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Laboratoire HP2, U1042, INSERM, Université Grenoble Alpes, Grenoble, France
| | - Patrick J Hanly
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Sleep Centre, Foothills Medical Centre, Calgary, AB, Canada
| | - Marc J Poulin
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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23
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Manukhina EB, Downey HF, Mallet RT. Role of Nitric Oxide in Cardiovascular Adaptation to Intermittent Hypoxia. Exp Biol Med (Maywood) 2016; 231:343-65. [PMID: 16565431 DOI: 10.1177/153537020623100401] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Hypoxia is one of the most frequently encountered stresses in health and disease. The duration, frequency, and severity of hypoxic episodes are critical factors determining whether hypoxia is beneficial or harmful. Adaptation to intermittent hypoxia has been demonstrated to confer cardiovascular protection against more severe and sustained hypoxia, and, moreover, to protect against other stresses, including ischemia. Thus, the direct and cross protective effects of adaptation to intermittent hypoxia have been used for treatment and prevention of a variety of diseases and to increase efficiency of exercise training. Evidence is mounting that nitric oxide (NO) plays a central role in these adaptive mechanisms. NO-dependent protective mechanisms activated by intermittent hypoxia include stimulation of NO synthesis as well as restriction of NO overproduction. In addition, alternative, nonenzymic sources of NO and negative feedback of NO synthesis are important factors in optimizing NO concentrations. The adaptive enhancement of NO synthesis and/or availability activates or increases expression of other protective factors, including heat shock proteins, antioxidants and prostaglandins, making the protection more robust and sustained. Understanding the role of NO in mechanisms of adaptation to hypoxia will support development of therapies to prevent and treat hypoxic or ischemic damage to organs and cells and to increase adaptive capabilities of the organism.
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24
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Chen YC, Inagaki T, Fujii Y, Schwenke DO, Tsuchimochi H, Edgley AJ, Umetani K, Zhang Y, Kelly DJ, Yoshimoto M, Nagai H, Evans RG, Kuwahira I, Shirai M, Pearson JT. Chronic intermittent hypoxia accelerates coronary microcirculatory dysfunction in insulin-resistant Goto-Kakizaki rats. Am J Physiol Regul Integr Comp Physiol 2016; 311:R426-39. [DOI: 10.1152/ajpregu.00112.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/30/2016] [Indexed: 12/20/2022]
Abstract
Chronic intermittent hypoxia (IH) induces oxidative stress and inflammation, which impair vascular endothelial function. Long-term insulin resistance also leads to endothelial dysfunction. We determined, in vivo, whether the effects of chronic IH and insulin resistance on endothelial function augment each other. Male 12-wk-old Goto-Kakizaki (GK) and Wistar control rats were subjected to normoxia or chronic IH (90-s N2, 5% O2 at nadir, 90-s air, 20 cycles/h, 8 h/day) for 4 wk. Coronary endothelial function was assessed using microangiography with synchrotron radiation. Imaging was performed at baseline, during infusion of acetylcholine (ACh, 5 μg·kg−1·min−1) and then sodium nitroprusside (SNP, 5 μg·kg−1·min−1), after blockade of both nitric oxide (NO) synthase (NOS) with Nω-nitro-l-arginine methyl ester (l-NAME, 50 mg/kg) and cyclooxygenase (COX, meclofenamate, 3 mg/kg), and during subsequent ACh. In GK rats, coronary vasodilatation in response to ACh and SNP was blunted compared with Wistar rats, and responses to ACh were abolished after blockade. In Wistar rats, IH blunted the ability of ACh or SNP to increase the number of visible vessels. In GK rats exposed to IH, neither ACh nor SNP were able to increase visible vessel number or caliber, and blockade resulted in marked vasoconstriction. Our findings indicate that IH augments the deleterious effects of insulin resistance on coronary endothelial function. They appear to increase the dependence of the coronary microcirculation on NO and/or vasodilator prostanoids, and greatly blunt the residual vasodilation in response to ACh after blockade of NOS/COX, presumably mediated by endothelium-derived hyperpolarizing factors.
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Affiliation(s)
- Yi Ching Chen
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Tadakatsu Inagaki
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Yutaka Fujii
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Daryl O. Schwenke
- Department of Physiology-Heart Otago, University of Otago, Dunedin, New Zealand
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Amanda J. Edgley
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Japan
| | - Yuan Zhang
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Darren J. Kelly
- St Vincent's Hospital, University of Melbourne, Melbourne, Australia
| | - Misa Yoshimoto
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - Hisashi Nagai
- Departments of Clinical Laboratory Medicine and Forensic Medicine, University of Tokyo, Tokyo, Japan
| | - Roger G. Evans
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Ichiro Kuwahira
- Department of Pulmonary Medicine, Tokai University Tokyo Hospital, Tokai University, Tokyo, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Japan
| | - James T. Pearson
- Cardiovascular Disease Program, Biosciences Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
- Monash Biomedical Imaging Facility, Melbourne, Australia; and
- Australian Synchrotron, Melbourne, Australia
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25
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Sforza E, Roche F. Chronic intermittent hypoxia and obstructive sleep apnea: an experimental and clinical approach. HYPOXIA (AUCKLAND, N.Z.) 2016; 4:99-108. [PMID: 27800512 PMCID: PMC5085272 DOI: 10.2147/hp.s103091] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Obstructive sleep apnea (OSA) is a prevalent sleep disorder considered as an independent risk factor for cardiovascular consequences, such as systemic arterial hypertension, ischemic heart disease, cardiac arrhythmias, metabolic disorders, and cognitive dysfunction. The pathogenesis of OSA-related consequence is assumed to be chronic intermittent hypoxia (IH) inducing alterations at the molecular level, oxidative stress, persistent systemic inflammation, oxygen sensor activation, and increase of sympathetic activity. Overall, these mechanisms have an effect on vessel permeability and are considered to be important factors for explaining vascular, metabolic, and cognitive OSA-related consequences. The present review attempts to examine together the research paradigms and clinical studies on the effect of acute and chronic IH and the potential link with OSA. We firstly describe the literature data on the mechanisms activated by acute and chronic IH at the experimental level, which are very helpful and beneficial to explaining OSA consequences. Then, we describe in detail the effect of IH in patients with OSA that we can consider "the human model" of chronic IH. In this way, we can better understand the specific pathophysiological mechanisms proposed to explain the consequences of IH in OSA.
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Affiliation(s)
- Emilia Sforza
- Service de Physiologie Clinique et de l’Exercice, Pole NOL, CHU, EA SNA-EPIS 4607, Faculté de Médecine J. Lisfranc, UJM Saint-Etienne, Université de Lyon, Saint-Etienne, France
| | - Fréderic Roche
- Service de Physiologie Clinique et de l’Exercice, Pole NOL, CHU, EA SNA-EPIS 4607, Faculté de Médecine J. Lisfranc, UJM Saint-Etienne, Université de Lyon, Saint-Etienne, France
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26
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Drager LF, Polotsky VY, O'Donnell CP, Cravo SL, Lorenzi-Filho G, Machado BH. Translational approaches to understanding metabolic dysfunction and cardiovascular consequences of obstructive sleep apnea. Am J Physiol Heart Circ Physiol 2015; 309:H1101-11. [PMID: 26232233 DOI: 10.1152/ajpheart.00094.2015] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 07/22/2015] [Indexed: 12/17/2022]
Abstract
Obstructive sleep apnea (OSA) is known to be independently associated with several cardiovascular diseases including hypertension, myocardial infarction, and stroke. To determine how OSA can increase cardiovascular risk, animal models have been developed to explore the underlying mechanisms and the cellular and end-organ targets of the predominant pathophysiological disturbance in OSA-intermittent hypoxia. Despite several limitations in translating data from animal models to the clinical arena, significant progress has been made in our understanding of how OSA confers increased cardiovascular risk. It is clear now that the hypoxic stress associated with OSA can elicit a broad spectrum of pathological systemic events including sympathetic activation, systemic inflammation, impaired glucose and lipid metabolism, and endothelial dysfunction, among others. This review provides an update of the basic, clinical, and translational advances in our understanding of the metabolic dysfunction and cardiovascular consequences of OSA and highlights the most recent findings and perspectives in the field.
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Affiliation(s)
- Luciano F Drager
- Hypertension Unit, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil; Hypertension Unit, Renal Division, University of São Paulo Medical School, São Paulo, Brazil;
| | - Vsevolod Y Polotsky
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Christopher P O'Donnell
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Sergio L Cravo
- Department of Physiology, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, Brazil
| | - Geraldo Lorenzi-Filho
- Sleep Laboratory, Pulmonary Division, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil; and
| | - Benedito H Machado
- Department of Physiology, School of Medicine of Ribeirao Preto, University of São Paulo, São Paulo, Brazil
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27
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Gozal D, Farré R, Nieto FJ. Obstructive sleep apnea and cancer: Epidemiologic links and theoretical biological constructs. Sleep Med Rev 2015; 27:43-55. [PMID: 26447849 DOI: 10.1016/j.smrv.2015.05.006] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/21/2015] [Accepted: 05/25/2015] [Indexed: 12/19/2022]
Abstract
Sleep disorders have emerged as highly prevalent conditions in the last 50-75 y. Along with improved understanding of such disorders, the realization that perturbations in sleep architecture and continuity may initiate, exacerbate or modulate the phenotypic expression of multiple diseases including cancer has gained increased attention. Furthermore, the intermittent hypoxia that is attendant to sleep disordered breathing, has recently been implicated in increased incidence and more adverse prognosis of cancer. The unifying conceptual framework linking these associations proposes that increased sympathetic activity and/or alterations in immune function, particularly affecting innate immune cellular populations, underlie the deleterious effects of sleep disorders on tumor biology. In this review, the epidemiological evidence linking disrupted sleep and intermittent hypoxia to oncological outcomes, and the potential biological underpinnings of such associations as illustrated by experimental murine models will be critically appraised. The overarching conclusion appears supportive in the formulation of an hypothetical framework, in which fragmented sleep and intermittent hypoxia may promote changes in multiple signalosomes and transcription factors that can not only initiate malignant transformation, but will also alter the tumor microenvironment, disrupt immunosurveillance, and thus hasten tumor proliferation and increase local and metastatic invasion. Future bench-based experimental studies as well as carefully conducted and controlled clinical epidemiological studies appear justified for further exploration of these hypotheses.
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Affiliation(s)
- David Gozal
- Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, IL, USA.
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona-IDIBAPS, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - F Javier Nieto
- Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
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28
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Iturriaga R, Andrade DC, Del Rio R. Enhanced carotid body chemosensory activity and the cardiovascular alterations induced by intermittent hypoxia. Front Physiol 2014; 5:468. [PMID: 25520668 PMCID: PMC4251310 DOI: 10.3389/fphys.2014.00468] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 11/14/2014] [Indexed: 02/03/2023] Open
Abstract
The carotid body (CB) plays a main role in the maintenance of the oxygen homeostasis. The hypoxic stimulation of the CB increases the chemosensory discharge, which in turn elicits reflex sympathetic, cardiovascular, and ventilatory adjustments. An exacerbate carotid chemosensory activity has been associated with human sympathetic-mediated diseases such as hypertension, insulin resistance, heart failure, and obstructive sleep apnea (OSA). Indeed, the CB chemosensory discharge becomes tonically hypereactive in experimental models of OSA and heart failure. Chronic intermittent hypoxia (CIH), a main feature of OSA, enhances CB chemosensory baseline discharges in normoxia and in response to hypoxia, inducing sympathetic overactivity and hypertension. Oxidative stress, increased levels of ET-1, Angiotensin II and pro-inflammatory cytokines, along with a reduced production of NO in the CB, have been associated with the enhanced carotid chemosensory activity. In this review, we will discuss new evidence supporting a main role for the CB chemoreceptor in the autonomic and cardiorespiratory alterations induced by intermittent hypoxia, as well as the molecular mechanisms involved in the CB chemosensory potentiation.
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Affiliation(s)
- Rodrigo Iturriaga
- Laboratorio de Neurobiología, Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile Santiago, Chile
| | - David C Andrade
- Laboratorio de Neurobiología, Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Center of Biomedical Research, Universidad Autónoma de Chile Santiago, Chile
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29
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Lucking EF, O'Halloran KD, Jones JFX. Increased cardiac output contributes to the development of chronic intermittent hypoxia-induced hypertension. Exp Physiol 2014; 99:1312-24. [DOI: 10.1113/expphysiol.2014.080556] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Eric F. Lucking
- UCD School of Medicine and Medical Science; University College Dublin; Dublin 4 Ireland
| | - Ken D. O'Halloran
- Department of Physiology; School of Medicine; University College Cork; Cork Ireland
| | - James F. X. Jones
- UCD School of Medicine and Medical Science; University College Dublin; Dublin 4 Ireland
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30
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Abstract
Lung ventilation fluctuates widely with behavior but arterial PCO2 remains stable. Under normal conditions, the chemoreflexes contribute to PaCO2 stability by producing small corrective cardiorespiratory adjustments mediated by lower brainstem circuits. Carotid body (CB) information reaches the respiratory pattern generator (RPG) via nucleus solitarius (NTS) glutamatergic neurons which also target rostral ventrolateral medulla (RVLM) presympathetic neurons thereby raising sympathetic nerve activity (SNA). Chemoreceptors also regulate presympathetic neurons and cardiovagal preganglionic neurons indirectly via inputs from the RPG. Secondary effects of chemoreceptors on the autonomic outflows result from changes in lung stretch afferent and baroreceptor activity. Central respiratory chemosensitivity is caused by direct effects of acid on neurons and indirect effects of CO2 via astrocytes. Central respiratory chemoreceptors are not definitively identified but the retrotrapezoid nucleus (RTN) is a particularly strong candidate. The absence of RTN likely causes severe central apneas in congenital central hypoventilation syndrome. Like other stressors, intense chemosensory stimuli produce arousal and activate circuits that are wake- or attention-promoting. Such pathways (e.g., locus coeruleus, raphe, and orexin system) modulate the chemoreflexes in a state-dependent manner and their activation by strong chemosensory stimuli intensifies these reflexes. In essential hypertension, obstructive sleep apnea and congestive heart failure, chronically elevated CB afferent activity contributes to raising SNA but breathing is unchanged or becomes periodic (severe CHF). Extreme CNS hypoxia produces a stereotyped cardiorespiratory response (gasping, increased SNA). The effects of these various pathologies on brainstem cardiorespiratory networks are discussed, special consideration being given to the interactions between central and peripheral chemoreflexes.
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Affiliation(s)
- Patrice G Guyenet
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia
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31
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Diogo LN, Monteiro EC. The efficacy of antihypertensive drugs in chronic intermittent hypoxia conditions. Front Physiol 2014; 5:361. [PMID: 25295010 PMCID: PMC4170135 DOI: 10.3389/fphys.2014.00361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 09/03/2014] [Indexed: 12/22/2022] Open
Abstract
Sleep apnea/hypopnea disorders include centrally originated diseases and obstructive sleep apnea (OSA). This last condition is renowned as a frequent secondary cause of hypertension (HT). The mechanisms involved in the pathogenesis of HT can be summarized in relation to two main pathways: sympathetic nervous system stimulation mediated mainly by activation of carotid body (CB) chemoreflexes and/or asphyxia, and, by no means the least important, the systemic effects of chronic intermittent hypoxia (CIH). The use of animal models has revealed that CIH is the critical stimulus underlying sympathetic activity and hypertension, and that this effect requires the presence of functional arterial chemoreceptors, which are hyperactive in CIH. These models of CIH mimic the HT observed in humans and allow the study of CIH independently without the mechanical obstruction component. The effect of continuous positive airway pressure (CPAP), the gold standard treatment for OSA patients, to reduce blood pressure seems to be modest and concomitant antihypertensive therapy is still required. We focus this review on the efficacy of pharmacological interventions to revert HT associated with CIH conditions in both animal models and humans. First, we explore the experimental animal models, developed to mimic HT related to CIH, which have been used to investigate the effect of antihypertensive drugs (AHDs). Second, we review what is known about drug efficacy to reverse HT induced by CIH in animals. Moreover, findings in humans with OSA are cited to demonstrate the lack of strong evidence for the establishment of a first-line antihypertensive regimen for these patients. Indeed, specific therapeutic guidelines for the pharmacological treatment of HT in these patients are still lacking. Finally, we discuss the future perspectives concerning the non-pharmacological and pharmacological management of this particular type of HT.
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Affiliation(s)
- Lucilia N Diogo
- Centro de Estudos de Doenças Crónicas, CEDOC, NOVA Medical School/Faculdade de Ciências Médicas, Universidade Nova de Lisboa Lisboa, Portugal
| | - Emília C Monteiro
- Centro de Estudos de Doenças Crónicas, CEDOC, NOVA Medical School/Faculdade de Ciências Médicas, Universidade Nova de Lisboa Lisboa, Portugal
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32
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Navarrete-Opazo A, Mitchell GS. Therapeutic potential of intermittent hypoxia: a matter of dose. Am J Physiol Regul Integr Comp Physiol 2014; 307:R1181-97. [PMID: 25231353 DOI: 10.1152/ajpregu.00208.2014] [Citation(s) in RCA: 281] [Impact Index Per Article: 28.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Intermittent hypoxia (IH) has been the subject of considerable research in recent years, and triggers a bewildering array of both detrimental and beneficial effects in multiple physiological systems. Here, we review the extensive literature concerning IH and its impact on the respiratory, cardiovascular, immune, metabolic, bone, and nervous systems. One major goal is to define relevant IH characteristics leading to safe, protective, and/or therapeutic effects vs. pathogenesis. To understand the impact of IH, it is essential to define critical characteristics of the IH protocol under investigation, including potentially the severity of hypoxia within episodes, the duration of hypoxic episodes, the number of hypoxic episodes per day, the pattern of presentation across time (e.g., within vs. consecutive vs. alternating days), and the cumulative time of exposure. Not surprisingly, severe/chronic IH protocols tend to be pathogenic, whereas any beneficial effects are more likely to arise from modest/acute IH exposures. Features of the IH protocol most highly associated with beneficial vs. pathogenic outcomes include the level of hypoxemia within episodes and the number of episodes per day. Modest hypoxia (9-16% inspired O2) and low cycle numbers (3-15 episodes per day) most often lead to beneficial effects without pathology, whereas severe hypoxia (2-8% inspired O2) and more episodes per day (48-2,400 episodes/day) elicit progressively greater pathology. Accumulating evidence suggests that "low dose" IH (modest hypoxia, few episodes) may be a simple, safe, and effective treatment with considerable therapeutic potential for multiple clinical disorders.
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Affiliation(s)
- Angela Navarrete-Opazo
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Gordon S Mitchell
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin
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33
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Almendros I, Wang Y, Gozal D. The polymorphic and contradictory aspects of intermittent hypoxia. Am J Physiol Lung Cell Mol Physiol 2014; 307:L129-40. [PMID: 24838748 DOI: 10.1152/ajplung.00089.2014] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Intermittent hypoxia (IH) has been extensively studied during the last decade, primarily as a surrogate model of sleep apnea. However, IH is a much more pervasive phenomenon in human disease, is viewed as a potential therapeutic approach, and has also been used in other disciplines, such as in competitive sports. In this context, adverse outcomes involving cardiovascular, cognitive, metabolic, and cancer problems have emerged in obstructive sleep apnea-based studies, whereas beneficial effects of IH have also been identified. Those a priori contradictory findings may not be as contradictory as initially thought. Indeed, the opposite outcomes triggered by IH can be explained by the specific characteristics of the large diversity of IH patterns applied in each study. The balance between benefits and injury appears to primarily depend on the ability of the organism to respond and activate adaptive mechanisms to IH. In this context, the adaptive or maladaptive responses can be generally predicted by the frequency, severity, and duration of IH. However, the presence of underlying conditions such as hypertension or obesity, as well as age, sex, or genotypic variance, may be important factors tilting the balance between an appropriate homeostatic response and decompensation. Here, the two possible facets of IH as derived from human and experimental animal settings will be reviewed.
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Affiliation(s)
- Isaac Almendros
- Department of Pediatrics, Comer Children's Hospital, Pritzker School of Medicine, The University of Chicago, Chicago, Illinois
| | - Yang Wang
- Department of Pediatrics, Comer Children's Hospital, Pritzker School of Medicine, The University of Chicago, Chicago, Illinois
| | - David Gozal
- Department of Pediatrics, Comer Children's Hospital, Pritzker School of Medicine, The University of Chicago, Chicago, Illinois
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34
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Nitric oxide and superoxide anion balance in rats exposed to chronic and long term intermittent hypoxia. BIOMED RESEARCH INTERNATIONAL 2014; 2014:610474. [PMID: 24719876 PMCID: PMC3955675 DOI: 10.1155/2014/610474] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/15/2014] [Indexed: 11/18/2022]
Abstract
Work at high altitude in shifts exposes humans to a new form of chronic intermittent hypoxia, with still unknown health consequences. We have established a rat model resembling this situation, which develops a milder form of right ventricular hypertrophy and pulmonary artery remodelling compared to continuous chronic exposure. We aimed to compare the alterations in pulmonary artery nitric oxide (NO) availability induced by these forms of hypoxia and the mechanisms implicated. Rats were exposed for 46 days to normoxia or hypobaric hypoxia, either continuous (CH) or intermittent (2 day shifts, CIH2x2), and assessed: NO and superoxide anion availability (fluorescent indicators and confocal microscopy); expression of phosphorylated endothelial NO synthase (eNOS), NADPH-oxidase (p22phox), and 3-nitrotyrosine (western blotting); and NADPH-oxidase location (immunohistochemistry). Compared to normoxia, (1) NO availability was reduced and superoxide anion was increased in both hypoxic groups, with a larger effect in CH, (2) eNOS expression was only reduced in CH, (3) NADPH-oxidase was similarly increased in both hypoxic groups, and (4) 3-nitrotyrosine was increased to a larger extent in CH. In conclusion, intermittent hypoxia reduces NO availability through superoxide anion destruction, without reducing its synthesis, while continuous hypoxia affects both, producing larger nitrosative damage which could be related to the more severe cardiovascular alterations.
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Badran M, Ayas N, Laher I. Insights into obstructive sleep apnea research. Sleep Med 2014; 15:485-95. [PMID: 24824769 DOI: 10.1016/j.sleep.2014.01.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 01/03/2014] [Accepted: 01/08/2014] [Indexed: 01/11/2023]
Abstract
Moderate to severe obstructive sleep apnea (OSA) occurs in 10-17% of middle aged men and 3-9% of middle-aged women with a higher prevalence among obese subjects. This condition is an independent risk factor for many cardiovascular diseases. Intermittent hypoxia is a major pathophysiologic character of OSA; it can lead to oxidative stress and inflammation, which in their turn cause endothelial dysfunction, a hallmark of atherosclerosis. Many animal models have been designed to mimic OSA in human patients to allow more in-depth investigation of biological and cellular mechanisms of this condition. This review discusses the cardiovascular outcomes of OSA and some of the animal models that are being used to investigate it.
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Affiliation(s)
- Mohammad Badran
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Najib Ayas
- Divisions of Critical Care and Respiratory Medicine, Department of Medicine, University of British Columbia, Sleep Disorders Program, UBC Hospital, Division of Critical Care Medicine, Providence Health Care, Vancouver, BC, Canada
| | - Ismail Laher
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
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Sharpe AL, Calderon AS, Andrade MA, Cunningham JT, Mifflin SW, Toney GM. Chronic intermittent hypoxia increases sympathetic control of blood pressure: role of neuronal activity in the hypothalamic paraventricular nucleus. Am J Physiol Heart Circ Physiol 2013; 305:H1772-80. [PMID: 24097432 DOI: 10.1152/ajpheart.00592.2013] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Like humans with sleep apnea, rats exposed to chronic intermittent hypoxia (CIH) experience arterial hypoxemias and develop hypertension characterized by exaggerated sympathetic nerve activity (SNA). To gain insights into the poorly understood mechanisms that initiate sleep apnea/CIH-associated hypertension, experiments were performed in rats exposed to CIH for only 7 days. Compared with sham-treated normoxic control rats, CIH-exposed rats (n = 8 rats/group) had significantly increased hematocrit (P < 0.001) and mean arterial pressure (MAP; P < 0.05). Blockade of ganglionic transmission caused a significantly (P < 0.05) greater reduction of MAP in rats exposed to CIH than control rats (n = 8 rats/group), indicating a greater contribution of SNA in the support of MAP even at this early stage of CIH hypertension. Chemical inhibition of neuronal discharge in the hypothalamic paraventricular nucleus (PVN) (100 pmol muscimol) had no effect on renal SNA but reduced lumbar SNA (P < 0.005) and MAP (P < 0.05) more in CIH-exposed rats (n = 8) than control rats (n = 7), indicating that CIH increased the contribution of PVN neuronal activity in the support of lumbar SNA and MAP. Because CIH activates brain regions controlling body fluid homeostasis, the effects of internal carotid artery injection of hypertonic saline were tested and determined to increase lumbar SNA more (P < 0.05) in CIH-exposed rats than in control rats (n = 9 rats/group). We conclude that neurogenic mechanisms are activated early in the development of CIH hypertension such that elevated MAP relies on increased sympathetic tonus and ongoing PVN neuronal activity. The increased sensitivity of Na(+)/osmosensitive circuitry in CIH-exposed rats suggests that early neuroadaptive responses among body fluid regulatory neurons could contribute to the initiation of CIH hypertension.
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Affiliation(s)
- Amanda L Sharpe
- Department of Pharmaceutical Sciences, Feik School of Pharmacy, University of the Incarnate Word, San Antonio, Texas
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Guo QH, Tian YL, Wang Z, Li AY, Ma ZH, Guo YJ, Weiss JW, Ji ES, Chu L. Endothelin receptors in augmented vasoconstrictor responses to endothelin-1 in chronic intermittent hypoxia. Clin Exp Pharmacol Physiol 2013; 40:449-57. [DOI: 10.1111/1440-1681.12109] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Qiu-Hong Guo
- Department of Pharmacology; Hebei Medical University; Shijiazhuang; China
| | - Yi-Long Tian
- Department of Physiology and; Hebei Medical University; Shijiazhuang; China
| | - Zhuo Wang
- Department of Physiology and; Hebei Medical University; Shijiazhuang; China
| | - Ai-Ying Li
- Department of Biochemistry; Hebei Medical University; Shijiazhuang; China
| | - Zhi-Hong Ma
- Department of Pharmacology; Hebei Medical University; Shijiazhuang; China
| | - Ya-Jing Guo
- Department of Physiology and; Hebei Medical University; Shijiazhuang; China
| | - J Woodrow Weiss
- Division of Pulmonary; Critical Care and Sleep Medicine; Beth Israel Deaconess Medical Center; Boston; MA; USA
| | - En-Sheng Ji
- Department of Physiology and; Hebei Medical University; Shijiazhuang; China
| | - Li Chu
- Department of Pharmacology; Hebei Medical University; Shijiazhuang; China
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38
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Obstructive sleep apnea, oxidative stress and cardiovascular disease: lessons from animal studies. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:234631. [PMID: 23533685 PMCID: PMC3603718 DOI: 10.1155/2013/234631] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Accepted: 01/22/2013] [Indexed: 01/31/2023]
Abstract
Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular (CV) diseases such as arterial hypertension, heart failure, and stroke. Based on human research, sympathetic activation, inflammation, and oxidative stress are thought to play major roles in the pathophysiology of OSA-related CV diseases. Animal models of OSA have shown that endothelial dysfunction, vascular remodelling, and systemic and pulmonary arterial hypertension as well as heart failure can develop in response to chronic intermittent hypoxia (CIH). The available animal data are clearly in favour of oxidative stress playing a key role in the development of all of these CV manifestations of OSA. Presumably, the oxidative stress is due to an activation of NADPH oxidase and other free oxygen radicals producing enzymes within the CV system as evidenced by data from knockout mice and pharmacological interventions. It is hoped that animal models of OSA-related CV disease will continue to contribute to a deeper understanding of their underlying pathophysiology and will foster the way for the development of cardioprotective treatment options other than conventional CPAP therapy.
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Wang B, Yan B, Song D, Ye X, Liu SF. Chronic intermittent hypoxia down-regulates endothelial nitric oxide synthase expression by an NF-κB-dependent mechanism. Sleep Med 2012; 14:165-71. [PMID: 23266106 DOI: 10.1016/j.sleep.2012.10.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Revised: 10/03/2012] [Accepted: 10/28/2012] [Indexed: 10/27/2022]
Abstract
OBJECTIVES Patients with obstructive sleep apnea have an impaired endothelium-dependent vasodilator response. The mechanisms underlying this impairment remain unclear. We tested the hypothesis that chronic intermittent hypoxia (CIH) impairs endothelium-dependent vasodilatation by NF-κB-mediated down-regulation of endothelial nitric oxide synthase (eNOS) expression. METHODS Wild type (WT) mice and mice deficient in NF-κB p50 or TNF-α gene were exposed to sham or CIH. Aortic NF-κB activity and aortic expression of TNF-α were determined. Aortic and mesenteric artery levels of eNOS expression were examined and their correlation to endothelium-dependent vasodilator response in vitro and vasodepressor response in vivo were analyzed. RESULTS WT mice exposed to CIH for five to eight weeks showed significantly reduced eNOS protein expression in aortas and mesenteric arteries, associated with significantly blunted vasodilator and vasodepressor responses to acetylcholine, but not to sodium nitroprusside. CIH activated NF-κB, which preceded TNF-α up-regulation and eNOS down-regulation. NF-κB p50 gene deletion blocked NF-κB activation, inhibited TNF-α expression, prevented eNOS down-regulation and reversed the impaired endothelium-dependent vasodepressor response induced by CIH. TNF-α knockout prevented CIH-induced eNOS down-regulation and restored the endothelium-dependent vasodepressor response. CONCLUSIONS CIH exposure impairs endothelium-dependent vasodilator mechanism by stimulating NF-κB-mediated TNF-α generation, which in turn, down-regulates eNOS expression, resulting in an impaired endothelium-dependent vasodilatation.
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Affiliation(s)
- Baoshan Wang
- Department of Otolaryngology and Head and Neck Surgery, The First Hospital of Hebei Medical University, Shijiazhuang, China.
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Moraes DJ, Zoccal DB, Machado BH. Medullary Respiratory Network Drives Sympathetic Overactivity and Hypertension in Rats Submitted to Chronic Intermittent Hypoxia. Hypertension 2012; 60:1374-80. [DOI: 10.1161/hypertensionaha.111.189332] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Davi J.A. Moraes
- From the Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil (D.J.A.M., B.H.M.); Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil (D.B.Z.)
| | - Daniel B. Zoccal
- From the Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil (D.J.A.M., B.H.M.); Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil (D.B.Z.)
| | - Benedito H. Machado
- From the Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil (D.J.A.M., B.H.M.); Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil (D.B.Z.)
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Circulating Microparticles from Patients with Obstructive Sleep Apnea Enhance Vascular Contraction. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 181:1473-82. [DOI: 10.1016/j.ajpath.2012.06.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 06/19/2012] [Accepted: 06/26/2012] [Indexed: 11/24/2022]
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Weiss JW, Liu Y, Li X, Ji ES. Nitric oxide and obstructive sleep apnea. Respir Physiol Neurobiol 2012; 184:192-6. [PMID: 22951245 DOI: 10.1016/j.resp.2012.08.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 08/11/2012] [Accepted: 08/13/2012] [Indexed: 01/31/2023]
Abstract
Obstructive sleep apnea is a common disease, affecting 16% of the working age population. Although sleep apnea has a well-established connection to daytime sleepiness presumably mediated through repetitive sleep disruption, some other consequences are less well understood. Clinical, epidemiological, and physiological investigations have demonstrated a connection between sleep apnea and daytime hypertension. The elevation of arterial pressure is evident during waking, when patients are not hypoxic, and is mediated by sustained sympathoexcitation and by altered peripheral vascular reactivity. This review summarizes data suggesting that both the sympathoexcitation and the altered vascular reactivity are, at least in part, a consequence of reduced expression of nitric oxide synthase, in neural tissue and in endothelium. Reduced nitric oxide generation in central and peripheral sites of sympathoregulation and in endothelium together may, in part, explain the elevations in waking pressures observed in sleep apnea patients.
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Affiliation(s)
- J Woodrow Weiss
- Division of Pulmonary, Critical Care, & Sleep Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, United States.
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Marcus NJ, Philippi NR, Bird CE, Li YL, Schultz HD, Morgan BJ. Effect of AT1 receptor blockade on intermittent hypoxia-induced endothelial dysfunction. Respir Physiol Neurobiol 2012; 183:67-74. [PMID: 22728949 PMCID: PMC3409315 DOI: 10.1016/j.resp.2012.05.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 05/04/2012] [Accepted: 05/29/2012] [Indexed: 02/07/2023]
Abstract
Chronic intermittent hypoxia (CIH) raises arterial pressure, impairs vasodilator responsiveness, and increases circulating angiotensin II (Ang II); however, the role of Ang II in CIH-induced vascular dysfunction is unknown. Rats were exposed to CIH or room air (NORM), and a subset of these animals was treated with losartan (Los) during the exposure period. After 28 days, vasodilatory responses to acetylcholine or nitroprusside were measured in isolated gracilis arteries. Superoxide levels and Ang II receptor protein expression were measured in saphenous arteries. After 28 days, arterial pressure was increased and acetylcholine-induced vasodilation was blunted in CIH vs. NORM, and this was prevented by Los. Responses to nitroprusside and superoxide levels did not differ between CIH and NORM. Expression of AT(2)R was decreased and the AT(1)R:AT(2)R ratio was increased in CIH vs. NORM, but this was unaffected by Los. These results indicate that the blood pressure elevation and endothelial dysfunction associated with CIH is dependent, at least in part, on RAS signaling.
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Affiliation(s)
- Noah J Marcus
- John Rankin Laboratory of Pulmonary Medicine, University of Wisconsin, Madison, WI 53706-1532, USA.
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Naghshin J, Rodriguez RH, Davis EM, Romano LC, McGaffin KR, O'Donnell CP. Chronic intermittent hypoxia exposure improves left ventricular contractility in transgenic mice with heart failure. J Appl Physiol (1985) 2012; 113:791-8. [PMID: 22773770 DOI: 10.1152/japplphysiol.00185.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We previously reported the unexpected finding that 4 wk of exposure to intermittent hypoxia (IH), which simulates the hypoxic stress of obstructive sleep apnea, improved LV cardiac function in healthy, lean C57BL/6J mice. The purpose of the present study was to assess the impact of 4 wk of IH on cardiac function in a transgenic murine model that exhibits a natural history of heart failure. We hypothesized that IH exposure would exacerbate cardiac decompensation in heart failure. Adult male FVB (wild type) and transgenic mice with cardiac overexpression of tumor necrosis factor α (TNF-αTG) at 10-12 wk of age were exposed to 4 wk of IH (nadir inspired oxygen 5-6% at 60 cycles/h for 12 h during light period) or intermittent air (IA) as control. Cardiac function was assessed by echocardiography and pressure-volume loop analyses, and mRNA and protein expression were performed on ventricular homogenates. TNF-αTG mice exposed to IA exhibited impaired LV contractility and increased LV dilation associated with markedly elevated cardiac expression of atrial natriuretic peptide and brain natriuretic peptide compared with wild-type mice. When wild-type FVB mice were exposed to IH, they exhibited increases in arterial pressure and dP/dt(max), consistent with our previous report in C57BL/6J mice. Surprisingly, we found that TNF-αTG mice exposed to IH showed a reduction in end-diastolic volume (38.7 ± 3.8 to 22.2 ± 2.1 ul; P < 0.01) and an increase in ejection fraction (29.4 ± 2.5 to 41.9 ± 3.1%; P < 0.05). In contrast to our previous study in C56Bl/6J mice, neither FVB nor TNF-αTG mice exhibited an upregulation in β-adrenergic expression or cAMP in response to IH exposure. We conclude that 4 wk of exposure to IH in mice induces adaptive responses that improve cardiac function in not only healthy animals but also in animals with underlying heart failure.
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Affiliation(s)
- Jahan Naghshin
- Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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Gupte SA, Wolin MS. Relationships between vascular oxygen sensing mechanisms and hypertensive disease processes. Hypertension 2012; 60:269-75. [PMID: 22710643 DOI: 10.1161/hypertensionaha.112.190702] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Sachin A Gupte
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, AL, USA
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Julien CA, Kinkead R, Joseph V, Bairam A. Neonatal Intermittent Hypoxia Induces Persistent Alteration of Baroreflex in Adult Male Rats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 758:179-83. [DOI: 10.1007/978-94-007-4584-1_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Golbidi S, Badran M, Ayas N, Laher I. Cardiovascular consequences of sleep apnea. Lung 2011; 190:113-32. [PMID: 22048845 DOI: 10.1007/s00408-011-9340-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 10/03/2011] [Indexed: 12/25/2022]
Abstract
Sleep apnea is a common health concern that is characterized by repetitive episodes of asphyxia. This condition has been linked to serious long-term adverse effects such as hypertension, metabolic dysregulation, and cardiovascular disease. Although the mechanism for the initiation and aggravation of cardiovascular disease has not been fully elucidated, oxidative stress and subsequent endothelial dysfunction play major roles. Animal models, which have the advantage of being free of comorbidities and/or behavioral variables (that commonly occur in humans), allow invasive measurements under well-controlled experimental conditions, and as such are useful tools in the study of the pathophysiological mechanisms of sleep apnea. This review summarizes currently available information on the cardiovascular consequences of sleep apnea and briefly describes common experimental approaches useful to sleep apnea in different animal models.
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Affiliation(s)
- Saeid Golbidi
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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Manukhina EB, Jasti D, Vanin AF, Downey HF. Intermittent hypoxia conditioning prevents endothelial dysfunction and improves nitric oxide storage in spontaneously hypertensive rats. Exp Biol Med (Maywood) 2011; 236:867-73. [PMID: 21652603 DOI: 10.1258/ebm.2011.011023] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although intermittent hypoxia is often associated with hypertension, experimental and clinical studies have demonstrated definite antihypertensive effects of some intermittent hypoxia conditioning (IHC) regimens. Mechanisms of this antihypertensive response are unknown. Endothelial dysfunction related to disturbed synthesis and/or reduced availability of nitric oxide (NO) has been linked to hypertension. Thus, experiments were conducted to determine if IHC can improve endothelium-dependent relaxation and formation of releasable vascular NO stores of young (4-8-week-old) spontaneously hypertensive rats (SHR). Rats were subjected to either IHC (9.5-10% O(2), 5-10 min, 5-8 times per day, 20 d) or to sham conditioning. Endothelium-dependent relaxation to acetylcholine was measured in norepinephrine-precontracted, isolated aortic rings, and the size of NO stores was evaluated by percent relaxation to N-acetylcysteine (NAC), which releases stored NO. The capacity of aortic rings for NO storage was evaluated by the relaxation to NAC after prior incubation with an NO donor. IHC significantly suppressed the development of hypertension in young SHR. Endothelial function decreased from 54.7 ± 4.6% to 28.1 ± 6.4% relaxation to acetylcholine after 20 d of sham IHC, whereas endothelial function was sustained (60.3 ± 6.0% relaxation) in IHC rats. IHC also induced formation of available NO stores and enhanced the capacity of aortic rings to store NO. Therefore, the antihypertensive effect of IHC in young SHR is associated with prevention of endothelial dysfunction and with increased accumulation of NO stores in vascular walls.
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Affiliation(s)
- Eugenia B Manukhina
- Department of Integrative Physiology, University of North Texas Health Science Center, 3500 Camp Bowie Blvd, Fort Worth, TX 76107, USA
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Feng J, Zhang D, Chen B. Endothelial mechanisms of endothelial dysfunction in patients with obstructive sleep apnea. Sleep Breath 2011; 16:283-94. [PMID: 21479903 DOI: 10.1007/s11325-011-0519-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/23/2011] [Accepted: 03/30/2011] [Indexed: 12/12/2022]
Abstract
BACKGROUND Obstructive sleep apnea (OSA) occurs in 2% of middle-aged women and 4% of middle-aged men in the general population and the prevalence is much higher in specific patient groups. Intermittent hypoxia (IH, oxygen desaturation and re-oxygenation) cycle, a major pathophysiologic character of OSA, and the physiological responses this evokes are thought to be responsible for its association with increased cardiovascular morbidity and mortality. Endothelial dysfunction, resulting from IH and as a key early event in atherosclerosis, was demonstrated repeatedly in patients with OSA and in animal models of IH, providing an important mechanistic link between the acute cyclical IH during sleep and the increased prevalence of chronic vascular diseases. CONCLUSIONS From this work, we conclude that IH from OSA may result in endothelial dysfunction, as a potential promoter of atherosclerosis, through nitric oxide unavailability, oxidative stress and inflammation, cell apoptosis, the crosstalk between endothelial cells and circulating inflammatory cells, microparticles, and damage repairing process. Though effective continuous positive airway pressure (CPAP) may specifically improve endothelial function, more controlled larger interventional trials that will include multiple centers and randomized allocation of CPAP therapy are needed to see if such changes are reversible before cause and effect can be implied finally, while further studies on cellular and animal level are also needed to elucidate molecular biologic/pathologic pathways.
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Affiliation(s)
- Jing Feng
- Respiratory Department of Tianjin Medical University General Hospital, Tianjin, 300052, China
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Silva AQ, Schreihofer AM. Altered sympathetic reflexes and vascular reactivity in rats after exposure to chronic intermittent hypoxia. J Physiol 2011; 589:1463-76. [PMID: 21242253 DOI: 10.1113/jphysiol.2010.200691] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Exposure to chronic intermittent hypoxia (CIH) yields persistent elevations in sympathetic nerve activity (SNA) and mean arterial pressure(MAP)with exaggerated sympathetic chemoreflexes. We examined the impact of CIH upon other sympathoexcitatory reflexes and a potential central mechanism underlying the altered regulation of SNA.Male Sprague-Dawley rats were exposed to CIH for 2 weeks (40 s at 6% O2 every 9 min, 8 h day⁻¹). After exposure to CIH, urethane-anaesthetized, vagotomized, ventilated, paralysed rats had significantly elevated MAP, splanchnic SNA, and rate of phrenic nerve discharge (PND; P<0.05). Elimination of SNA by ganglionic blockade produced a larger fall in MAP in rats exposed to CIH (P<0.05). Like acute hypoxia, stimulation of the sciatic nerve or the nasal mucosa evoked greater increases in SNA after exposure to CIH (P<0.05). In addition, acute hypoxia promoted exaggerated increases in PND amplitude after CIH (P<0.05). In contrast, the nasopharyngeal reflex evoked exaggerated increases in SNA during apnoea. These sympathoexcitatory reflexes are mediated by glutamatergic activation of the rostral ventrolateral medulla (RVLM), and accordingly, microinjections of glutamate into RVLM evoked larger increases in SNA after CIH (P<0.05). Paradoxically, none of these exaggerated acute rises in SNA was accompanied by enhanced pressor responses. Reduced adrenergic vascular reactivity may contribute to the blunted sympathetically mediated pressor responses, because bolus doses of phenylephrine evoked attenuated pressor responses after CIH (P<0.01).These data suggest exposure to CIH facilitates activation of SNA, potentially by changes within the RVLM. However, the exaggerated rises in SNA are not dependent upon stimulation of inspiratory drive. Although elevated SNA may contribute to CIH-induced hypertension, reduced adrenergic vascular reactivity buffers the cardiovascular impact of exaggerated acute rises in SNA.
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Affiliation(s)
- Ana Q Silva
- Department of Physiology, Medical College of Georgia, Augusta, GA, USA
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