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Robinson G, Zielstorff M, Sevilla R, Vanko A, Sinz C, Cicmil M, Zhang W, Bettano K. Multimodal Imaging Reveals that Sustained Inhibition of HIF-Prolyl Hydroxylases Induces Opposing Effects on Right and Left Ventricular Function in Healthy Rats. Mol Imaging Biol 2024; 26:179-187. [PMID: 38057646 DOI: 10.1007/s11307-023-01876-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/17/2023] [Accepted: 11/02/2023] [Indexed: 12/08/2023]
Abstract
PURPOSE Hypoxia-inducible factor (HIF) drives transcription of critical hypoxia response genes, increasing the production of red blood cells in low oxygen conditions. In the absence of hypoxia, HIF is degraded by prolyl hydroxylases (HIF-PHs). Pharmacological HIF-PH inhibition stabilizes HIF and is being studied as a treatment for anemia. However, like sustained hypoxia, HIF-PH inhibition may increase pulmonary arterial pressure leading to right ventricular hypertrophy. The aim of this study was to assess the cardiac effects of sustained pharmacological HIF-PH inhibition using multimodal imaging, blood analysis, and histology. METHODS Rats were dosed daily with a pan HIF-PH inhibitor or vehicle for 4 weeks followed by a 2-week washout period and underwent longitudinal magnetic resonance imaging (MRI) and echocardiography to simultaneously assess RV and LV function. Blood samples from weeks four and six were analyzed to determine red blood cell composition. Histology was performed on the cardiac tissue from a subset of rats at weeks four and six to assess structural effects. RESULTS Imaging revealed that RV ejection fraction was reduced in animals receiving HIF-PH inhibitor and resulted in RV hypertrophy. Interestingly, HIF-PH inhibition had the opposite effect on the left ventricle (LV), increasing contractility measured by LV ejection fraction. LV effects were reversed by week six, while RV effects (functional and structural) were sustained. CONCLUSION These opposing cardiac effects of HIF-PH inhibition warrant further study to both understand the potential negative effects on RV structure and function and investigate the therapeutic potential of increased LV contractility for conditions like heart failure.
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Affiliation(s)
- Gain Robinson
- Translational Imaging, Merck & Co., Inc., Rahway, NJ, USA.
| | - Mark Zielstorff
- Quantitative Biosciences, Merck & Co., Inc., Rahway, NJ, USA
| | - Raquel Sevilla
- Translational Imaging, Merck & Co., Inc., Rahway, NJ, USA
| | - Amy Vanko
- Translational Imaging, Merck & Co., Inc., Rahway, NJ, USA
- Moderna, Inc., Cambridge, MA, USA
| | - Christopher Sinz
- Discovery Chemistry, Merck & Co., Inc., Rahway, NJ, USA
- Octant, Inc., Emeryville, CA, USA
| | - Milenko Cicmil
- Quantitative Biosciences, Merck & Co., Inc., Rahway, NJ, USA
- Cure Ventures Management, L.P., Newport Beach, CA, USA
| | - Weisheng Zhang
- Translational Imaging, Merck & Co., Inc., Rahway, NJ, USA
- Takeda Oncology, Cambridge, MA, USA
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Arnaud C, Billoir E, de Melo Junior AF, Pereira SA, O'Halloran KD, Monteiro EC. Chronic intermittent hypoxia-induced cardiovascular and renal dysfunction: from adaptation to maladaptation. J Physiol 2023; 601:5553-5577. [PMID: 37882783 DOI: 10.1113/jp284166] [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: 07/07/2023] [Accepted: 10/12/2023] [Indexed: 10/27/2023] Open
Abstract
Chronic intermittent hypoxia (CIH) is the dominant pathological feature of human obstructive sleep apnoea (OSA), which is highly prevalent and associated with cardiovascular and renal diseases. CIH causes hypertension, centred on sympathetic nervous overactivity, which persists following removal of the CIH stimulus. Molecular mechanisms contributing to CIH-induced hypertension have been carefully delineated. However, there is a dearth of knowledge on the efficacy of interventions to ameliorate high blood pressure in established disease. CIH causes endothelial dysfunction, aberrant structural remodelling of vessels and accelerates atherosclerotic processes. Pro-inflammatory and pro-oxidant pathways converge on disrupted nitric oxide signalling driving vascular dysfunction. In addition, CIH has adverse effects on the myocardium, manifesting atrial fibrillation, and cardiac remodelling progressing to contractile dysfunction. Sympatho-vagal imbalance, oxidative stress, inflammation, dysregulated HIF-1α transcriptional responses and resultant pro-apoptotic ER stress, calcium dysregulation, and mitochondrial dysfunction conspire to drive myocardial injury and failure. CIH elaborates direct and indirect effects in the kidney that initially contribute to the development of hypertension and later to chronic kidney disease. CIH-induced morphological damage of the kidney is dependent on TLR4/NF-κB/NLRP3/caspase-1 inflammasome activation and associated pyroptosis. Emerging potential therapies related to the gut-kidney axis and blockade of aryl hydrocarbon receptors (AhR) are promising. Cardiorenal outcomes in response to intermittent hypoxia present along a continuum from adaptation to maladaptation and are dependent on the intensity and duration of exposure to intermittent hypoxia. This heterogeneity of OSA is relevant to therapeutic treatment options and we argue the need for better stratification of OSA phenotypes.
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Affiliation(s)
- Claire Arnaud
- Université Grenoble-Alpes INSERM U1300, Laboratoire HP2, Grenoble, France
| | - Emma Billoir
- Université Grenoble-Alpes INSERM U1300, Laboratoire HP2, Grenoble, France
| | | | - Sofia A Pereira
- iNOVA4Health, NOVA Medical School, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine & Health, University College Cork, Cork, Ireland
| | - Emilia C Monteiro
- iNOVA4Health, NOVA Medical School, Universidade NOVA de Lisboa, Lisboa, Portugal
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Koritala BSC, Lee YY, Gaspar LS, Bhadri SS, Su W, Wu G, Francey LJ, Ruben MD, Gong MC, Hogenesch JB, Smith DF. Obstructive sleep apnea in a mouse model is associated with tissue-specific transcriptomic changes in circadian rhythmicity and mean 24-hour gene expression. PLoS Biol 2023; 21:e3002139. [PMID: 37252926 PMCID: PMC10228805 DOI: 10.1371/journal.pbio.3002139] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 04/25/2023] [Indexed: 06/01/2023] Open
Abstract
Intermittent hypoxia (IH) is a major clinical feature of obstructive sleep apnea (OSA). The mechanisms that become dysregulated after periods of exposure to IH are unclear, particularly in the early stages of disease. The circadian clock governs a wide array of biological functions and is intimately associated with stabilization of hypoxia-inducible factors (HIFs) under hypoxic conditions. In patients, IH occurs during the sleep phase of the 24-hour sleep-wake cycle, potentially affecting their circadian rhythms. Alterations in the circadian clock have the potential to accelerate pathological processes, including other comorbid conditions that can be associated with chronic, untreated OSA. We hypothesized that changes in the circadian clock would manifest differently in those organs and systems known to be impacted by OSA. Using an IH model to represent OSA, we evaluated circadian rhythmicity and mean 24-hour expression of the transcriptome in 6 different mouse tissues, including the liver, lung, kidney, muscle, heart, and cerebellum, after a 7-day exposure to IH. We found that transcriptomic changes within cardiopulmonary tissues were more affected by IH than other tissues. Also, IH exposure resulted in an overall increase in core body temperature. Our findings demonstrate a relationship between early exposure to IH and changes in specific physiological outcomes. This study provides insight into the early pathophysiological mechanisms associated with IH.
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Affiliation(s)
- Bala S. C. Koritala
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Yin Yeng Lee
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Laetitia S. Gaspar
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Shweta S. Bhadri
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Wen Su
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, United States of America
| | - Gang Wu
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Lauren J. Francey
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Marc D. Ruben
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Ming C. Gong
- Department of Physiology, University of Kentucky, Lexington, Kentucky, United States of America
| | - John B. Hogenesch
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - David F. Smith
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
- Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- The Sleep Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- The Center for Circadian Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
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Jones AA, Framnes-DeBoer SN, Shipp A, Arble DM. Caloric restriction prevents obesity- and intermittent hypoxia-induced cardiac remodeling in leptin-deficient ob/ob mice. Front Physiol 2022; 13:963762. [PMID: 36160851 PMCID: PMC9493268 DOI: 10.3389/fphys.2022.963762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Intermittent hypoxia (IH), a key characteristic of obstructive sleep apnea, is independently associated with cardiometabolic impairment. While endogenous leptin levels may provide cardioprotective effects against hypoxia, leptin resistance is common among obese individuals presenting with obstructive sleep apnea. Methods: Here, we assessed left ventricle (LV) function using M-mode echocardiography in lean wild-type, calorically-restricted ob/ob, and obese ob/ob mice before and after 6 days of IH to determine how obesity and intermittent hypoxia interact to affect cardiac function independent of leptin signaling. Results: Calorically-restricting ob/ob mice for 4 weeks prior to IH exposure prevented weight gain (−2.1 ± 1.4 g) compared to free-fed ob/ob mice (8.7 ± 1.1 g). Free-fed ob/ob mice exhibited increased LV mass (0.713 ± 0.008 g) relative to wild-type mice (0.685 ± 0.004 g) and increased posterior wall thickness (0.089 ± 0.006 cm) relative to calorically-restricted ob/ob mice (0.072 ± 0.004 cm). Following 6 days of IH, free-fed ob/ob mice exhibited increases in cardiac output (44.81 ± 2.97 pre-IH vs. 57.14 ± 3.09 ml/min post-IH), LV diameter (0.400 ± 0.007 pre-IH vs. 0.428 ± 0.009 cm post-IH) and end diastolic volume (0.160 ± 0.007 pre-IH vs. 0.195 ± 0.012 ml post-IH) that were not detected in wild-type or calorically-restricted ob/ob mice. Conclusion: Caloric restriction can prevent obesity-induced LV hypertrophy and protect against acute IH-induced cardiac remodeling independent of leptin signaling. These findings may have clinical implications for obstructive sleep apnea.
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Affiliation(s)
- Aaron A. Jones
- Department of Biological Sciences, Marquette University, Milwaukee, WI, United States
| | | | - Arianne Shipp
- Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Clearwater, FL, United States
| | - Deanna M. Arble
- Department of Biological Sciences, Marquette University, Milwaukee, WI, United States
- *Correspondence: Deanna M. Arble,
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Sleep Breathing Disorders in Heart Failure. Cardiol Clin 2022; 40:183-189. [DOI: 10.1016/j.ccl.2021.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Zhang G, Zhou Y, Cao Z, Cheng X, Yue X, Zhao T, Zhao M, Zhao Y, Fan M, Zhu L. Preliminary Intermittent Hypoxia Training Alleviates the Damage of Sustained Normobaric Hypoxia on Human Hematological Indexes and Cerebral White Matter. High Alt Med Biol 2022; 23:273-283. [PMID: 35486840 DOI: 10.1089/ham.2021.0166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Zhang, Guangbo, Yanzhao Zhou, Zhengtao Cao, Xiang Cheng, Xiangpei Yue, Tong Zhao, Ming Zhao, Yongqi Zhao, Ming Fan, and Lingling Zhu. Preliminary intermittent hypoxia training alleviates the damage of sustained normobaric hypoxia on human hematological indexes and cerebral white matter. High Alt Med Biol. 00:000-000, 2022. Study Objectives: We aimed to examine the effects of preliminary intermittent hypoxia training (IHT) on human hematological indexes and cerebral white matter (WM) after exposure to a simulated altitude of 4,300 m. Methods: We recruited 20 young healthy volunteers. Participants were then randomized to either the IHT group (n = 10) or the control group (n = 10). We measured the physiological function of the control group at sea level and after exposure to a simulated altitude of 4,300 m, respectively. The IHT group performed the above tests at three time points: before and after hypoxia training, and after exposure to a simulated altitude of 4,300 m, respectively. Results: We found that mean SpO2 during day 10 of hypoxia training showed a significant increase compared with mean SpO2 on day 1 (88.3% ± 1.5% vs. 90.0% ± 1.6%, p < 0.05), and erythrocyte P50 of post-training was significantly increased compared with pretraining (37.8 ± 2.9 mmHg vs. 45.9 ± 6.4 mmHg, p < 0.05). Mean SpO2 measures after acute exposure to high altitude exhibited a significant difference, with the IHT group showing significantly greater SpO2 than the control group (73.8% ± 3.7% vs. 77.4% ± 3.2%, p < 0.05), and the Lake Louise Score was also lower than the control group (2.55 ± 2.1 vs. 6.67 ± 2.5, p < 0.05). After daily IHT, brain-derived neurotrophic factor plasma levels of participants in the IHT group did not change but significantly increased in response to high-altitude hypoxia (103.5% ± 70.4% vs. 29.7% ± 73.2%, p < 0.05). Interleukin-10 (IL-10) plasma level did not change before and after IHT in the IHT group, whereas the IL-10 plasma level of the control group after high-altitude exposure was significantly higher. Furthermore, we found that fractional anisotropy values in the left corticospinal tract and splenium of the corpus callosum in the IHT group were significantly higher than those in the control group after high-altitude hypoxia. Conclusions: These results demonstrate that IHT alleviates the damage of sustained normobaric hypoxia on human hematological indexes and cerebral WM.
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Affiliation(s)
- Guangbo Zhang
- Department of Neurobiology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China.,Department of Neurology, Kangjixintu Hospital, Renqiu, China
| | - Yanzhao Zhou
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Zhengtao Cao
- Department of Biomedical Engineering, Air Force Medical Center, PLA, Beijing, China
| | - Xiang Cheng
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Xiangpei Yue
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Tong Zhao
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Ming Zhao
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yongqi Zhao
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Ming Fan
- Department of Neurobiology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Lingling Zhu
- Department of Brain Protection and Plasticity, Beijing Institute of Basic Medical Sciences, Beijing, China
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7
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Visniauskas B, Perry JC, Gomes GN, Nogueira-Pedro A, Paredes-Gamero EJ, Tufik S, Chagas JR. Intermittent hypoxia changes the interaction of the kinin-VEGF system and impairs myocardial angiogenesis in the hypertrophic heart. Physiol Rep 2021; 9:e14863. [PMID: 33991464 PMCID: PMC8123545 DOI: 10.14814/phy2.14863] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/29/2021] [Accepted: 04/13/2021] [Indexed: 12/12/2022] Open
Abstract
Intermittent hypoxia (IH) is a feature of obstructive sleep apnea (OSA), a condition highly associated with hypertension-related cardiovascular diseases. Repeated episodes of IH contribute to imbalance of angiogenic growth factors in the hypertrophic heart, which is key in the progression of cardiovascular complications. In particular, the interaction between vascular endothelial growth factor (VEGF) and the kallikrein-kinin system (KKS) is essential for promoting angiogenesis. However, researchers have yet to investigate experimental models of IH that reproduce OSA, myocardial angiogenesis, and expression of KKS components. We examined temporal changes in cardiac angiogenesis in a mouse IH model. Adult male C57BI/6 J mice were implanted with Matrigel plugs and subjected to IH for 1-5 weeks with subsequent weekly histological evaluation of vascularization. Expression of VEGF and KKS components was also evaluated. After 3 weeks, in vivo myocardial angiogenesis and capillary density were decreased, accompanied by a late increase of VEGF and its type 2 receptor. Furthermore, IH increased left ventricular myocardium expression of the B2 bradykinin receptor, while reducing mRNA levels of B1 receptor. These results suggest that in IH, an unexpected response of the VEGF and KKS systems could explain the reduced capillary density and impaired angiogenesis in the hypoxic heart, with potential implications in hypertrophic heart malfunction.
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Affiliation(s)
- Bruna Visniauskas
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Juliana C Perry
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Guiomar N Gomes
- Departmento de Fisiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | | | | | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Jair R Chagas
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil.,Departamento de Biofísica, Universidade Federal de São Paulo, São Paulo, Brazil
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Khannous-Lleiffe O, Willis JR, Saus E, Cabrera-Aguilera I, Almendros I, Farré R, Gozal D, Farré N, Gabaldón T. A Mouse Model Suggests That Heart Failure and Its Common Comorbidity Sleep Fragmentation Have No Synergistic Impacts on the Gut Microbiome. Microorganisms 2021; 9:microorganisms9030641. [PMID: 33808770 PMCID: PMC8003359 DOI: 10.3390/microorganisms9030641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/11/2021] [Accepted: 03/15/2021] [Indexed: 12/19/2022] Open
Abstract
Heart failure (HF) is a common condition associated with a high rate of hospitalizations and adverse outcomes. HF is characterized by impairments of either the cardiac ventricular filling, ejection of blood capacity or both. Sleep fragmentation (SF) involves a series of short sleep interruptions that lead to fatigue and contribute to cognitive impairments and dementia. Both conditions are known to be associated with increased inflammation and dysbiosis of the gut microbiota. In the present study, mice were distributed into four groups, and subjected for four weeks to either HF, SF, both HF and SF, or left unperturbed as controls. We used 16S metabarcoding to assess fecal microbiome composition before and after the experiments. Evidence for distinct alterations in several bacterial groups and an overall decrease in alpha diversity emerged in HF and SF treatment groups. Combined HF and SF conditions, however, showed no synergism, and observed changes were not always additive, suggesting preliminarily that some of the individual effects of either HF or SF cancel each other out when applied concomitantly.
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Affiliation(s)
- Olfat Khannous-Lleiffe
- Barcelona Supercomputing Centre (BSC-CNS), 08034 Barcelona, Spain; (O.K.-L.); (J.R.W.); (E.S.)
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Jesse R. Willis
- Barcelona Supercomputing Centre (BSC-CNS), 08034 Barcelona, Spain; (O.K.-L.); (J.R.W.); (E.S.)
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Ester Saus
- Barcelona Supercomputing Centre (BSC-CNS), 08034 Barcelona, Spain; (O.K.-L.); (J.R.W.); (E.S.)
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
| | - Ignacio Cabrera-Aguilera
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (I.C.-A.); (I.A.); (R.F.)
- Department of Human Movement Sciences, Faculty of Health Sciences, School of Kinesiology, Universidad de Talca, Talca 3460000, Chile
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (I.C.-A.); (I.A.); (R.F.)
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (I.C.-A.); (I.A.); (R.F.)
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
| | - David Gozal
- Department of Child Health and Child Health Research Institute, The University of Missouri School of Medicine, Columbia, MO 65212, USA;
| | - Nuria Farré
- Heart Failure Unit, Department of Cardiology, Hospital del Mar (Parc de Salut Mar), 08003 Barcelona, Spain
- Heart Diseases Biomedical Research Group, IMIM (Hospital del Mar Medical Research Institute), 08003 Barcelona, Spain
- Department of Medicine, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
- Correspondence: (N.F.); (T.G.)
| | - Toni Gabaldón
- Barcelona Supercomputing Centre (BSC-CNS), 08034 Barcelona, Spain; (O.K.-L.); (J.R.W.); (E.S.)
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, 08028 Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), 08010 Barcelona, Spain
- Correspondence: (N.F.); (T.G.)
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9
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[Into thin air - Altitude training and hypoxic conditioning: From athlete to patient]. Rev Mal Respir 2021; 38:404-417. [PMID: 33722445 DOI: 10.1016/j.rmr.2021.02.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/15/2020] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Hypoxic exposure should be considered as a continuum, the effects of which depend on the dose and individual response to hypoxia. Hypoxic conditioning (HC) represents an innovative and promising strategy, ranging from improved human performance to therapeutic applications. STATE OF THE ART With the aim of improving sports performance, the effectiveness of hypoxic exposure, whether natural or simulated, is difficult to demonstrate because of the large variability of the protocols used. In therapeutics, the benefits of HC are described in many pathological conditions such as obesity or cardiovascular pathologies. If the HC benefits from a strong preclinical rationale, its application to humans remains limited. PERSPECTIVES Advances in training and acclimation will require greater personalization and precise periodization of hypoxic exposures. For patients, the harmonization of HC protocols, the identification of biomarkers and the development and subsequent validation of devices allowing a precise control of the hypoxic stimulus are necessary steps for the development of HC. CONCLUSIONS From the athlete to the patient, HC represents an innovative and promising field of research, ranging from the improvement of human performance to the prevention and treatment of certain pathologies.
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Détrait M, Pesse M, Calissi C, Bouyon S, Brocard J, Vial G, Pépin JL, Belaidi E, Arnaud C. Short-term intermittent hypoxia induces simultaneous systemic insulin resistance and higher cardiac contractility in lean mice. Physiol Rep 2021; 9:e14738. [PMID: 33682327 PMCID: PMC7937943 DOI: 10.14814/phy2.14738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/07/2021] [Accepted: 01/08/2021] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Intermittent hypoxia (IH) is the major feature of obstructive sleep apnea syndrome, well-known to induce cardiometabolic complications. We previously demonstrated that IH induces hyperinsulinemia and associated altered insulin signaling in adipose tissue, liver, and skeletal muscle, but impact of IH on cardiac insulin signaling and functional/structural consequences remains unknown. Therefore, the aims of this study were to investigate in both lean and obese mice the effects of chronic IH on the following: (1) cardiac insulin signaling and (2) cardiac remodeling and function. METHODS C57BL/6 J male mice were fed low-fat (LFD) or high-fat (HFD) diet for 20 weeks, and exposed to IH (21-5% FiO2, 60 s cycle, 8 h/day) or normoxia (N) for the last 6 weeks. Systemic insulin sensitivity was evaluated by an insulin tolerance test. Cardiac remodeling and contractile function were assessed by cardiac ultrasonography. Ultimately, hearts were withdrawn for biochemical and histological analysis. RESULTS In LFD mice, IH-induced hyperinsulinemia and systemic insulin resistance that were associated with increased phosphorylations of cardiac insulin receptor and Akt on Tyr1150 and Ser473 residues, respectively. In addition, IH significantly increased cardiac interstitial fibrosis and cardiac contractility. In the HFD group, IH did not exert any additional effect, nor on insulin/Akt signaling, nor on cardiac remodeling and function. CONCLUSION Our study suggests that, despite systemic insulin resistance, IH exposure mediates an adaptive cardiac response in lean but not in obese mice. Further studies are needed to investigate which specific mechanisms are involved and to determine the long-term evolution of cardiac responses to IH.
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Affiliation(s)
- Maximin Détrait
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Mélanie Pesse
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Clément Calissi
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Sophie Bouyon
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Jacques Brocard
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France.,University Lyon, ENS de Lyon, Inserm, CNRS SFR Biosciences, UCBL, Lyon, France
| | - Guillaume Vial
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Jean-Louis Pépin
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Elise Belaidi
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
| | - Claire Arnaud
- University Grenoble Alpes, Inserm, CHU Grenoble Alpes, Grenoble, France
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Cabrera-Aguilera I, Benito B, Tajes M, Farré R, Gozal D, Almendros I, Farré N. Chronic Sleep Fragmentation Mimicking Sleep Apnea Does Not Worsen Left-Ventricular Function in Healthy and Heart Failure Mice. Front Neurol 2020; 10:1364. [PMID: 31993015 PMCID: PMC6962346 DOI: 10.3389/fneur.2019.01364] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 12/10/2019] [Indexed: 12/30/2022] Open
Abstract
Aims: Obstructive sleep apnea (OSA) has been associated with heart failure (HF). Sleep fragmentation (SF), one of the main hallmarks of OSA, induces systemic inflammation, oxidative stress and sympathetic activation, hence potentially participating in OSA-induced cardiovascular consequences. However, whether SF per se is deleterious to heart function is unknown. The aim of this study was to non-invasively evaluate the effect of SF mimicking OSA on heart function in healthy mice and in mice with HF. Methods and Results: Forty C57BL/6J male mice were randomized into 4 groups: control sleep (C), sleep fragmentation (SF), isoproterenol-induced heart failure (HF), and mice subjected to both SF+HF. Echocardiography was performed at baseline and after 30 days to evaluate left ventricular end-diastolic (LVEDD) and end-systolic (LVESD) diameters, left ventricular ejection fraction (LVEF) and fraction shortening (FS). The effects of SF and HF on these parameters were assessed by two-way ANOVA. Mice with isoproterenol-induced HF had significant increases in LVEDD and LVESD, as well as a decreases in LVEF and FS (p = 0.013, p = 0.006, p = 0.027, and p = 0.047, respectively). However, no significant effects emerged with SF (p = 0.480, p = 0.542, p = 0.188, and p = 0.289, respectively). Conclusion: Chronic SF mimicking OSA did not induce echocardiographic changes in cardiac structure and function in both healthy and HF mice. Thus, the deleterious cardiac consequences of OSA are likely induced by other perturbations associated with this prevalent condition, or result from interactions with underlying comorbidities in OSA patients.
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Affiliation(s)
- Ignacio Cabrera-Aguilera
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- Departament of Human Movement Sciences, Faculty of Health Sciences, School of Kinesiology, Universidad de Talca, Talca, Chile
| | - Begoña Benito
- Department of Cardiology, Hospital del Mar, Barcelona, Spain
- Heart Diseases Biomedical Research Group, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
- Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marta Tajes
- Heart Diseases Biomedical Research Group, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - David Gozal
- Department of Child Health and Child Health Research Institute, The University of Missouri School of Medicine, Columbia, MO, United States
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Nuria Farré
- Heart Diseases Biomedical Research Group, IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain
- Department of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
- Heart Failure Unit, Department of Cardiology, Hospital del Mar, Barcelona, Spain
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12
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Intermittent Hypoxia Alleviates β-Aminopropionitrile Monofumarate Induced Thoracic Aortic Dissection in C57BL/6 Mice. Eur J Vasc Endovasc Surg 2019; 59:1000-1010. [PMID: 31879145 DOI: 10.1016/j.ejvs.2019.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 09/26/2019] [Accepted: 10/18/2019] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Thoracic aortic dissection (TAD) has a high mortality rate. Intermittent hypoxia (IH) triggers both harmful and beneficial effects in numerous physiological systems. The effects of IH on TAD development were explored in a mouse model. METHODS β-Aminopropionitrile monofumarate (BAPN) was used to induce TAD in C57BL/6 mice. Three week old male mice were treated with 1 g/kg/day BAPN in drinking water for four weeks and simultaneously subjected to IH (n = 30) (21%-5% O2, 90 s/cycle, 10 h/day, IH + BAPN group) or normoxia (n = 30) (21% O2, 24 h/day, BAPN group). Human VSMCs (HUASMCs) exposed to IH (30 min, 5% O2)/re-oxygenation (30 min, 21% O2) cycles with a maximum of 60 min/cycle to detect the effect of IH on HIF-1α and LOX via HIF-1α-siRNA. RESULTS It was found that BAPN administration significantly increased the lumen size and wall thickness of aortas compared with the normal group, but was significantly reversed by IH exposure. Additionally, IH exposure significantly increased the survival rate of BAPN induced TAD (70% vs. 40%). Furthermore, IH exposure reduced BAPN induced elastin breaks and apoptosis of vascular smooth muscle cells. IH exposure also reversed BAPN induced upregulation of inflammation and extracellular matrix (ECM) degradation. Real time polymerase chain reaction (RT-PCR) confirmed that IH inhibited inflammation and ECM degradation related genes interleukin (IL)-1β, IL-6, cathepsin S (Cat S), and matrix metalloproteinase 9 (MMP-9), but upregulated the ECM synthesis related genes lysyl oxidase (LOX) and collagen type I alpha2 (Col1a2) compared with the BAPN group. In vitro results suggest that IH promotes the expression of LOX via HIF-1α. CONCLUSION The results suggest that IH alleviates BAPN induced TAD in C57BL/6 mice.
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Oates CP, Ananthram M, Gottlieb SS. Management of Sleep Disordered Breathing in Patients with Heart Failure. Curr Heart Fail Rep 2018; 15:123-130. [PMID: 29616491 DOI: 10.1007/s11897-018-0387-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE OF REVIEW This paper reviews treatment options for sleep disordered breathing (SDB) in patients with heart failure. We sought to identify therapies for SDB with the best evidence for long-term use in patients with heart failure and to minimize uncertainties in clinical practice by examining frequently discussed questions: what is the role of continuous positive airway pressure (CPAP) in patients with heart failure? Is adaptive servo-ventilation (ASV) safe in patients with heart failure? To what extent is SDB a modifiable risk factor? RECENT FINDINGS Consistent evidence has demonstrated that the development of SDB in patients with heart failure is a poor prognostic indicator and a risk factor for cardiovascular mortality. However, despite numerous available interventions for obstructive sleep apnea and central sleep apnea, it remains unclear what effect these therapies have on patients with heart failure. To date, all major randomized clinical trials have failed to demonstrate a survival benefit with SDB therapy and one major study investigating the use of adaptive servo-ventilation demonstrated harm. Significant questions persist regarding the management of SDB in patients with heart failure. Until appropriately powered trials identify a treatment modality that increases cardiovascular survival in patients with SDB and heart failure, a patient's heart failure management should remain the priority of medical care.
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Affiliation(s)
- Connor P Oates
- School of Medicine, University of Maryland, Baltimore, MD, USA
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15
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Campillo N, Falcones B, Montserrat JM, Gozal D, Obeso A, Gallego-Martin T, Navajas D, Almendros I, Farré R. Frequency and magnitude of intermittent hypoxia modulate endothelial wound healing in a cell culture model of sleep apnea. J Appl Physiol (1985) 2017. [PMID: 28642292 DOI: 10.1152/japplphysiol.00077.2017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Intermittent hypoxia (IH) has been implicated in the cardiovascular consequences of obstructive sleep apnea (OSA). However, the lack of suitable experimental systems has precluded assessment as to whether IH is detrimental, protective, or both for the endothelium. The aim of the work was to determine the effects of frequency and amplitude of IH oxygenation swings on aortic endothelial wound healing. Monolayers of human primary endothelial cells were wounded and subjected to constant oxygenation (1%, 4%, 13%, or 20% O2) or IH at different frequencies (0.6, 6, or 60 cycles/h) and magnitude ranges (13-4% O2 or 20-1% O2), using a novel well-controlled system, with wound healing being measured after 24 h. Cell monolayer repair was similar at 20% O2 and 13% O2, but was considerably increased (approximately twofold) in constant hypoxia at 4% O2 The magnitude and frequency of IH considerably modulated wound healing. Cycles ranging 13-4% O2 at the lowest frequency (0.6 cycles/h) accelerated endothelial wound healing by 102%. However, for IH exposures consisting of 20% to 1% O2 oscillations, wound closure was reduced compared with oscillation in the 13-4% range (by 74% and 44% at 6 cycles/h and 0.6 cycles/h, respectively). High-frequency IH patterns simulating severe OSA (60 cycles/h) did not significantly modify endothelial wound closure, regardless of the oxygenation cycle amplitude. In conclusion, the frequency and magnitude of hypoxia cycling in IH markedly alter wound healing responses and emerge as key factors determining how cells will respond in OSA.NEW & NOTEWORTHY Intermittent hypoxia (IH) induces cardiovascular consequences in obstructive sleep apnea (OSA) patients. However, the vast array of frequencies and severities of IH previously employed in OSA-related experimental studies has led to controversial results on the effects of IH. By employing an optimized IH experimental system here, we provide evidence that the frequency and magnitude of IH markedly alter human aortic endothelial wound healing, emerging as key factors determining how cells respond in OSA.
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Affiliation(s)
- Noelia Campillo
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Bryan Falcones
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Josep M Montserrat
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Sleep Lab, Hospital Clinic Barcelona, Barcelona, Spain
| | - David Gozal
- Section of Pediatric Sleep Medicine, Department of Pediatrics, Pritzker School of Medicine, Biological Sciences Division, The University of Chicago, Chicago, Illinois
| | - Ana Obeso
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, El Instituto de Biología y Genética Molecular/Consejo Superior de Investigaciones Científicas, Valladolid, Spain
| | - Teresa Gallego-Martin
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, Universidad de Valladolid, El Instituto de Biología y Genética Molecular/Consejo Superior de Investigaciones Científicas, Valladolid, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Institut de Bioenginyeria de Catalunya, Barcelona, Spain; and
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomediques August Pi Sunyer, Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain; .,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain.,Institut d'Investigacions Biomediques August Pi Sunyer, Barcelona, Spain
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16
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Hrdlička J, Neckář J, Papoušek F, Vašinová J, Alánová P, Kolář F. Beneficial effect of continuous normobaric hypoxia on ventricular dilatation in rats with post-infarction heart failure. Physiol Res 2016; 65:867-870. [PMID: 27429114 DOI: 10.33549/physiolres.933308] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Adaptation to continuous normobaric hypoxia (CNH) protects the heart against ischemia/reperfusion injury but much less is known about its potential therapeutic effects. The aim of this study was to find out whether post-infarction exposure to CNH can attenuate the progression of heart failure. Ten-week-old male rats underwent myocardial infarction (MI) or sham operation. MI was induced by 60-min coronary artery occlusion. Seven days post-MI, the rats were randomly assigned to two groups: i) sedentary controls kept at room air and ii) rats exposed to CNH (12 % O(2), 3 weeks). Echocardiographic examination of the left ventricle (LV) was performed 3 days before surgery and 7, 14 and 28 days post-MI. MI resulted in a gradual increase in LV end-diastolic diameter (LVD(d)) compared to sham-operated animals. Fractional shortening (FS) decreased from 42.8 % before MI to 15.1 % on day 28 post-MI. CNH significantly attenuated ventricular dilatation without affecting scar area and FS. Our data suggest that prolonged exposure to CNH has certain potential to attenuate the progression of unfavorable changes in ventricular geometry induced by MI in rats.
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Affiliation(s)
- J Hrdlička
- Department of Developmental Cardiology, Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic.
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Jia W, Jian Z, Li J, Luo L, Zhao L, Zhou Y, Tang F, Xiao Y. Upregulated ATF6 contributes to chronic intermittent hypoxia-afforded protection against myocardial ischemia/reperfusion injury. Int J Mol Med 2016; 37:1199-208. [PMID: 27035093 PMCID: PMC4829135 DOI: 10.3892/ijmm.2016.2535] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 03/07/2016] [Indexed: 12/04/2022] Open
Abstract
In the present study, we investigated the role of activating transcription factor 6 (ATF6) in the mechanism by which chronic intermittent hypoxia (CIH) increases tolerance to myocardial ischemia/reperfusion (I/R). Experiments were conducted using a rat model of I/R injury in vivo and isolated Langendorff-perfused rat hearts ex vivo. The role of Akt in this process was also investigated in vitro using rat myoblast H9c2 cells. Cell viability was measured using a cell counting kit-8 assay. Lactate dehydrogenase (LDH) and creatine kinase cardiac isoenzyme activity were also measured as markers of cellular damage. ATF6, Akt and phosphorylated (p)-Akt expression was analyzed by western blot analysis. RNA interference (RNAi) was used to suppress ATF6 expression. We noted that ATF6 expression in the ventricular myocardium was significantly increased in rats exposed to CIH. Furthermore, we noted that CIH preserved cardiac function after I/R in vivo and improved post-ischemic recovery of myocardial performance in isolated rat hearts. ATF6 and p-Akt expression was upregulated in cultured H9c2 cells exposed to chronic mild hypoxia compared with those cultured under normoxic conditions. Chronic mild hypoxia attenuated subsequent simulated I/R injury in H9c2 cells (48 h), as evidenced by increased cell viability and decreased LDH activity. By contrast, decreased cell viability and increased LDH activity were observed in siRNA-ATF6-transfected H9c2 cells, with a concomitant reduction in p-Akt levels. These results indicated that ATF6 upregulation is involved in the mechanism by which CIH attenuates myocardial I/R injury, possibly through upregulation of p-Akt, which is a key regulator of cardiomyocyte survival.
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Affiliation(s)
- Weikun Jia
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Zhao Jian
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Jingwei Li
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Lin Luo
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Liang Zhao
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Yang Zhou
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Fuqin Tang
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
| | - Yingbin Xiao
- Department of Cardiovascular Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, P.R. China
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Abstract
We address adaptive vs. maladaptive responses to hypoxemia in healthy humans and hypoxic-tolerant species during wakefulness, sleep, and exercise. Types of hypoxemia discussed include short-term and life-long residence at high altitudes, the intermittent hypoxemia attending sleep apnea, or training regimens prescribed for endurance athletes. We propose that hypoxia presents an insult to O2 transport, which is poorly tolerated in most humans because of the physiological cost.
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Affiliation(s)
- Jerome A Dempsey
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; and
| | - Barbara J Morgan
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
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Guo X, Shang J, Deng Y, Yuan X, Zhu D, Liu H. Alterations in left ventricular function during intermittent hypoxia: Possible involvement of O-GlcNAc protein and MAPK signaling. Int J Mol Med 2015; 36:150-8. [PMID: 25936416 PMCID: PMC4494595 DOI: 10.3892/ijmm.2015.2198] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 04/17/2015] [Indexed: 11/12/2022] Open
Abstract
Obstructive sleep apnea, characterized by recurrent episodes of hypoxia [intermittent hypoxia (IH)], has been identified as a risk factor for cardiovascular diseases. The O-linked β-N-acetylglucosamine (O-GlcNAc) modification (O-GlcNAcylation) of proteins has important regulatory implications on the pathophysiology of cardiovascular disorders. In this study, we examined the role of O-GlcNAcylation in cardiac architecture and left ventricular function following IH. Rats were randomly assigned to a normoxia and IH group (2 min 21% O2; 2 min 6–8% O2). Left ventricular function, myocardial morphology and the levels of signaling molecules were then measured. IH induced a significant increase in blood pressure, associated with a gradually abnormal myocardial architecture. The rats exposed to 2 or 3 weeks of IH presented with augmented left ventricular systolic and diastolic function, which declined at week 4. Consistently, the O-GlcNAc protein and O-GlcNAcase (OGA) levels in the left ventricular tissues steadily increased following IH, reaching peak levels at week 3. The O-GlcNAc transferase (OGT), extracellular signal-regulated kinase 1/2 (ERK1/2) and the p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation levels were affected in an opposite manner. The phosphorylation of calcium/calmodulin-dependent protein kinase II (CaMKII) remained unaltered. In parallel, compared with exposure to normoxia, 4 weeks of IH augmented the O-GlcNAc protein, OGT, phosphorylated ERK1/2 and p38 MAPK levels, accompanied by a decrease in OGA levels and an increase in the levels of myocardial nuclear factor-κB (NF-κB), inflammatory cytokines, caspase-3 and cardiomyocyte apoptosis. Taken together, our suggest a possible involvement of O-GlcNAc protein and MAPK signaling in the alterations of left ventricular function and cardiac injury following IH.
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Affiliation(s)
- Xueling Guo
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
| | - Jin Shang
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
| | - Yan Deng
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
| | - Xiao Yuan
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
| | - Die Zhu
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
| | - Huiguo Liu
- Department of Respiratory and Critical Care Medicine, Tongji Hospital, Huazhong University of Science and Technology, Key Laboratory of Respiratory Disease of the Ministry of Health, Wuhan 430030, P.R. China
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20
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Verges S, Chacaroun S, Godin-Ribuot D, Baillieul S. Hypoxic Conditioning as a New Therapeutic Modality. Front Pediatr 2015; 3:58. [PMID: 26157787 PMCID: PMC4476260 DOI: 10.3389/fped.2015.00058] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/03/2015] [Indexed: 01/03/2023] Open
Abstract
Preconditioning refers to a procedure by which a single noxious stimulus below the threshold of damage is applied to the tissue in order to increase resistance to the same or even different noxious stimuli given above the threshold of damage. Hypoxic preconditioning relies on complex and active defenses that organisms have developed to counter the adverse consequences of oxygen deprivation. The protection it confers against ischemic attack for instance as well as the underlying biological mechanisms have been extensively investigated in animal models. Based on these data, hypoxic conditioning (consisting in recurrent exposure to hypoxia) has been suggested a potential non-pharmacological therapeutic intervention to enhance some physiological functions in individuals in whom acute or chronic pathological events are anticipated or existing. In addition to healthy subjects, some benefits have been reported in patients with cardiovascular and pulmonary diseases as well as in overweight and obese individuals. Hypoxic conditioning consisting in sessions of intermittent exposure to moderate hypoxia repeated over several weeks may induce hematological, vascular, metabolic, and neurological effects. This review addresses the existing evidence regarding the use of hypoxic conditioning as a potential therapeutic modality, and emphasizes on many remaining issues to clarify and future researches to be performed in the field.
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Affiliation(s)
- Samuel Verges
- Laboratoire HP2, Université Grenoble Alpes , Grenoble , France ; U1042, INSERM , Grenoble , France
| | - Samarmar Chacaroun
- Laboratoire HP2, Université Grenoble Alpes , Grenoble , France ; U1042, INSERM , Grenoble , France
| | - Diane Godin-Ribuot
- Laboratoire HP2, Université Grenoble Alpes , Grenoble , France ; U1042, INSERM , Grenoble , France
| | - Sébastien Baillieul
- Laboratoire HP2, Université Grenoble Alpes , Grenoble , France ; U1042, INSERM , Grenoble , France
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Mateika JH, El-Chami M, Shaheen D, Ivers B. Intermittent hypoxia: a low-risk research tool with therapeutic value in humans. J Appl Physiol (1985) 2014; 118:520-32. [PMID: 25549763 DOI: 10.1152/japplphysiol.00564.2014] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Intermittent hypoxia has generally been perceived as a high-risk stimulus, particularly in the field of sleep medicine, because it is thought to initiate detrimental cardiovascular, respiratory, cognitive, and metabolic outcomes. In contrast, the link between intermittent hypoxia and beneficial outcomes has received less attention, perhaps because it is not universally understood that outcome measures following exposure to intermittent hypoxia may be linked to the administered dose. The present review is designed to emphasize the less recognized beneficial outcomes associated with intermittent hypoxia. The review will consider the role intermittent hypoxia has in cardiovascular and autonomic adaptations, respiratory motor plasticity, and cognitive function. Each section will highlight the literature that contributed to the belief that intermittent hypoxia leads primarily to detrimental outcomes. The second segment of each section will consider the possible risks associated with experimentally rather than naturally induced intermittent hypoxia. Finally, the body of literature indicating that intermittent hypoxia initiates primarily beneficial outcomes will be considered. The overarching theme of the review is that the use of intermittent hypoxia in research investigations, coupled with reasonable safeguards, should be encouraged because of the potential benefits linked to the administration of a variety of low-risk intermittent hypoxia protocols.
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Affiliation(s)
- Jason H Mateika
- John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan; Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan; and Department of Internal Medicine, Wayne State University School of Medicine, Detroit, Michigan
| | - Mohamad El-Chami
- John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan; Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan; and
| | - David Shaheen
- John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan; Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan; and
| | - Blake Ivers
- John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan; Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan; and
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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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23
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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: 128] [Impact Index Per Article: 12.8] [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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Rodriguez RH, Bickta JL, Murawski P, O'Donnell CP. The impact of obesity and hypoxia on left ventricular function and glycolytic metabolism. Physiol Rep 2014; 2:e12001. [PMID: 24771695 PMCID: PMC4001880 DOI: 10.14814/phy2.12001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We have previously reported that 4 weeks of intermittent hypoxia (IH) exposure, mimicking the hypoxic stress of obstructive sleep apnea, produces compensatory increases in left ventricular (LV) contractility in lean C57BL/6J mice. In this study we compared the effects of 4 weeks IH to 4 weeks of sustained hypoxia (SH) on LV function and cardiac glycolysis in lean C57BL/6J mice and obese ob/ob mice at 10–12 weeks of age. The four exposure conditions were IH (nadir O2 [5–6%] at 60 cycles/h during the 12 h light period), SH (24 h inspired O2 [10%]), and control groups of intermittent air (IA) or room air. Cardiac function was assessed under isoflurane anesthesia (1–2%) by echocardiography and pressure–volume loop analysis and myocardial glycolytic rates were determined ex vivo using radiolabeled 3H‐glucose. Lean mice exposed to IH exhibited increases in contractile parameters which were associated with elevated glycolytic rates (3.4 vs. 5.7 μg/μL·g; P < 0.05). Ob/ob mice did not show any improvements in contractility after IH. Moreover, cardiac glycolytic rates and LV systolic and diastolic function did not differ from IA ob/ob controls. Following SH exposure, lean mice exhibited increased contractility and glycolytic rates (3.8 vs. 5.7 μg/μL·g; P < 0.05), however, LV lumen dimensions were reduced. In contrast, ob/ob mice exposed to SH show compromised systolic and diastolic function associated with unchanging glycolytic rates. These findings demonstrate that, in a murine model of obesity, an inability to increase glycolysis is associated with an absence of an adaptive cardiac response to IH and marked systolic and diastolic dysfunction in response to SH. The impact of obesity on left ventricular (LV) function and cardiac glycolytic responses to chronic 4 week exposure to intermittent hypoxia, mimicking the hypoxic stress of obstructive sleep apnea, or sustained hypoxia, mimicking altitude exposure, is unknown. We show that, in a murine model of obesity, an inability to increase glycolysis is associated with an absence of an adaptive cardiac response to intermittent hypoxia and marked systolic and diastolic dysfunction in response to sustained hypoxia.
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Affiliation(s)
- Rosa H Rodriguez
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
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25
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Milano G, Abruzzo PM, Bolotta A, Marini M, Terraneo L, Ravara B, Gorza L, Vitadello M, Burattini S, Curzi D, Falcieri E, von Segesser LK, Samaja M. Impact of the phosphatidylinositide 3-kinase signaling pathway on the cardioprotection induced by intermittent hypoxia. PLoS One 2013; 8:e76659. [PMID: 24124584 PMCID: PMC3790757 DOI: 10.1371/journal.pone.0076659] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 08/26/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Exposure to intermittent hypoxia (IH) may enhance cardiac function and protects heart against ischemia-reperfusion (I/R) injury. To elucidate the underlying mechanisms, we developed a cardioprotective IH model that was characterized at hemodynamic, biochemical and molecular levels. METHODS Mice were exposed to 4 daily IH cycles (each composed of 2-min at 6-8% O2 followed by 3-min reoxygenation for 5 times) for 14 days, with normoxic mice as controls. Mice were then anesthetized and subdivided in various subgroups for analysis of contractility (pressure-volume loop), morphology, biochemistry or resistance to I/R (30-min occlusion of the left anterior descending coronary artery (LAD) followed by reperfusion and measurement of the area at risk and infarct size). In some mice, the phosphatidylinositide 3-kinase (PI3K) inhibitor wortmannin was administered (24 µg/kg ip) 15 min before LAD. RESULTS We found that IH did not induce myocardial hypertrophy; rather both contractility and cardiac function improved with greater number of capillaries per unit volume and greater expression of VEGF-R2, but not of VEGF. Besides increasing the phosphorylation of protein kinase B (Akt) and the endothelial isoform of NO synthase with respect to control, IH reduced the infarct size and post-LAD proteins carbonylation, index of oxidative damage. Administration of wortmannin reduced the level of Akt phosphorylation and worsened the infarct size. CONCLUSION We conclude that the PI3K/Akt pathway is crucial for IH-induced cardioprotection and may represent a viable target to reduce myocardial I/R injury.
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Affiliation(s)
- Giuseppina Milano
- Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
- Laboratorio di Biologia Vascolare e Medicina Regenerativa, Centro Cardiologico Monzino, IRCSS, Milan, Italy
- * E-mail:
| | - Provvidenza Maria Abruzzo
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Alessandra Bolotta
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Marina Marini
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy
| | - Laura Terraneo
- Department of Health Science, University of Milan, Milan, Italy
| | - Barbara Ravara
- Dipartimento di Scienze Biomediche, Università di Padova, Padova, Italy
| | - Luisa Gorza
- Dipartimento di Scienze Biomediche, Università di Padova, Padova, Italy
| | | | | | - Davide Curzi
- DiSTeVA, University of Urbino “Carlo Bo”, Urbino, Italy
| | | | | | - Michele Samaja
- Department of Health Science, University of Milan, Milan, Italy
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26
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Chen D, Fang F, Yang Y, Chen J, Xu G, Xu Y, Gao Y. Brahma-related gene 1 (Brg1) epigenetically regulates CAM activation during hypoxic pulmonary hypertension. Cardiovasc Res 2013; 100:363-73. [PMID: 24042015 DOI: 10.1093/cvr/cvt214] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
AIMS Establishment of an inflammatory milieu following elevated leukocyte adhesion to the vascular endothelium, which is mediated by transcriptional activation of cell adhesion molecules (CAMs), contributes to the pathogenesis of chronic hypoxia-induced pulmonary hypertension (HPH). The epigenetic switch that dictates CAM transactivation in response to hypoxia in endothelial cells leading up to HPH is not fully appreciated. METHODS AND RESULTS We report here that brahma-related gene 1 (Brg1) and brahma (Brm), two catalytic components of the mammalian chromatin remodelling complex, were induced in cultured endothelial cells challenged with hypoxia in vitro as well as in pulmonary arteries in an animal model of HPH. Over-expression of Brg1/Brm enhanced, while the depletion of Brg1/Brm attenuated, CAM transactivation and adhesion of leukocytes. Endothelial-specific deletion of Brg1/Brm ameliorated vascular inflammation and HPH in mice. Chromatin immunoprecipitation (ChIP) and re-ChIP assays revealed that hypoxia up-regulated the occupancies of Brg1 and Brm on CAM promoters in a nuclear factor κB (NF-κB) -dependent manner. Finally, Brg1 and Brm activated CAM transcription by altering the chromatin structure surrounding the CAM promoters. CONCLUSION Our data suggest that Brg1 provides the crucial epigenetic link to hypoxia-induced CAM induction and leukocyte adhesion that engenders endothelial malfunction and pathogenesis of HPH. As such, targeting Brg1 in endothelial cells may yield promising strategies in the intervention and/or prevention of HPH.
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Affiliation(s)
- Dewei Chen
- Department of Pathophysiology and High Altitude Physiology, College of High Altitude Military Medicine, Chongqing 400038, China
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27
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Davis EM, O'Donnell CP. Rodent models of sleep apnea. Respir Physiol Neurobiol 2013; 188:355-61. [PMID: 23722067 DOI: 10.1016/j.resp.2013.05.022] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/17/2013] [Accepted: 05/21/2013] [Indexed: 12/31/2022]
Abstract
Rodent models of sleep apnea have long been used to provide novel insight into the generation and predisposition to apneas as well as to characterize the impact of sleep apnea on cardiovascular, metabolic, and psychological health in humans. Given the significant body of work utilizing rodent models in the field of sleep apnea, the aims of this review are three-fold: first, to review the use of rodents as natural models of sleep apnea; second, to provide an overview of the experimental interventions employed in rodents to simulate sleep apnea; third, to discuss the refinement of rodent models to further our understanding of breathing abnormalities that occur during sleep. Given mounting evidence that sleep apnea impairs cognitive function, reduces quality of life, and exacerbates the course of multiple chronic diseases, rodent models will remain a high priority as a tool to interrogate both the pathophysiology and sequelae of breathing related abnormalities during sleep and to improve approaches to diagnosis and therapy.
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Affiliation(s)
- Eric M Davis
- Department of Medicine, Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
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28
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Current World Literature. Curr Opin Cardiol 2013; 28:369-79. [DOI: 10.1097/hco.0b013e328360f5be] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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