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Ravaglia IC, Jasodanand V, Bhatnagar S, Grafe LA. Sex differences in body temperature and neural power spectra in response to repeated restraint stress. Stress 2024; 27:2320780. [PMID: 38414377 PMCID: PMC10989713 DOI: 10.1080/10253890.2024.2320780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 02/12/2024] [Indexed: 02/29/2024] Open
Abstract
Repeated stress is associated with an increased risk of developing psychiatric illnesses such as post-traumatic stress disorder (PTSD), which is more common in women, yet the neurobiology behind this sex difference is unknown. Habituation to repeated stress is impaired in PTSD, and recent preclinical studies have shown that female rats do not habituate as fully as male rats to repeated stress, which leads to impairments in cognition and sleep. Further research should examine sex differences after repeated stress in other relevant measures, such as body temperature and neural activity. In this study, we analyzed core body temperature and EEG power spectra in adult male and female rats during restraint, as well as during sleep transitions following stress. We found that core body temperature of male rats habituated to repeated restraint more fully than female rats. Additionally, we found that females had a higher average beta band power than males on both days of restraint, indicating higher levels of arousal. Lastly, we observed that females had lower delta band power than males during sleep transitions on Day 1 of restraint, however, females demonstrated higher delta band power than males by Day 5 of restraint. This suggests that it may take females longer to initiate sleep recovery compared with males. These findings indicate that there are differences in the physiological and neural processes of males and females after repeated stress. Understanding the way that the stress response is regulated in both sexes can provide insight into individualized treatment for stress-related disorders.
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Affiliation(s)
- IC Ravaglia
- Bryn Mawr College, Department of Psychology, Bryn Mawr, PA, USA
| | - V Jasodanand
- Bryn Mawr College, Department of Psychology, Bryn Mawr, PA, USA
| | - S Bhatnagar
- Department of Anesthesiology and Critical Care, Children’s Hospital of Philadelphia, Philadelphia, PA, USA
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - LA Grafe
- Bryn Mawr College, Department of Psychology, Bryn Mawr, PA, USA
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2
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Zhang K, Wang C, Wu Y, Xu Z. Identification of novel biomarkers in obstructive sleep apnea via integrated bioinformatics analysis and experimental validation. PeerJ 2023; 11:e16608. [PMID: 38077447 PMCID: PMC10702330 DOI: 10.7717/peerj.16608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/15/2023] [Indexed: 12/18/2023] Open
Abstract
Background Obstructive sleep apnea (OSA) is a complex and multi-gene inherited disease caused by both genetic and environmental factors. However, due to the high cost of diagnosis and complex operation, its clinical application is limited. This study aims to explore potential target genes associated with OSA and establish a corresponding diagnostic model. Methods This study used microarray datasets from the Gene Expression Omnibus (GEO) database to identify differentially expressed genes (DEGs) related to OSA and perform functional annotation and pathway analysis. The study employed multi-scale embedded gene co-expression network analysis (MEGENA) combined with least absolute shrinkage and selection operator (LASSO) regression analysis to select hub genes and construct a diagnostic model for OSA. In addition, the study conducted correlation analysis between hub genes and OSA-related genes, immunoinfiltration, gene set enrichment analysis (GSEA), miRNA network analysis, and identified potential transcription factors (TFs) and targeted drugs for hub genes. Finally, the study used chronic intermittent hypoxia (CIH) mouse model to simulate OSA hypoxic conditions and verify the expression of hub genes in CIH mice. Results In this study, a total of 401 upregulated genes and 275 downregulated genes were identified, and enrichment analysis revealed that these differentially expressed genes may be associated with pathways such as vasculature development, cellular response to cytokine stimulus, and negative regulation of cell population proliferation. Through MEGENA combined with LASSO regression, seven OSA hub genes were identified, including C12orf54, FOS, GPR1, OR9A4, MYO5B, RAB39B, and KLHL4. The diagnostic model constructed based on these genes showed strong stability. The expression levels of hub genes were significantly correlated with the expression levels of OSA-related genes and mainly acted on pathways such as the JAK/STAT signaling pathway and the cytosolic DNA-sensing pathway. Drug-target predictions for hub genes were made using the Connectivity Map (CMap) database and the Drug-Gene Interaction database (Dgidb), which identified targeted therapeutic drugs for the hub genes. In vivo experiments showed that the hub genes were all decreasing in the OSA mouse model. Conclusions This study identified novel biomarkers for OSA and established a reliable diagnostic model. The transcriptional changes identified may help to reveal the pathogenesis, mechanisms, and sequelae of OSA.
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Affiliation(s)
- Kai Zhang
- Beijing Children’s Hospital, Department of Respiratory Medicine, Beijing, People’s Republic of China
| | - Caizhen Wang
- The Second Hospital of Hebei Medical University, Pediatric Intensive Care Unit, Shijiazhuang, Hebei, People’s Republic of China
| | - Yunxiao Wu
- Beijing Children’s Hospital, Department of Respiratory Medicine, Beijing, People’s Republic of China
| | - Zhifei Xu
- Beijing Children’s Hospital, Department of Respiratory Medicine, Beijing, People’s Republic of China
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Farnham MMJ, Tallapragada VJ, O'Connor ET, Nedoboy PE, Dempsey B, Mohammed S, Fong AY, Lung MSY, Derakhshan F, Wilson RJA, Pilowsky PM. PACAP-PAC1 Receptor Activation Is Necessary for the Sympathetic Response to Acute Intermittent Hypoxia. Front Neurosci 2019; 13:881. [PMID: 31496933 PMCID: PMC6712064 DOI: 10.3389/fnins.2019.00881] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/05/2019] [Indexed: 01/29/2023] Open
Abstract
Repetitive hypoxia is a key feature of obstructive sleep apnoea (OSA), a condition characterized by intermittent airways obstruction. Patients with OSA present with persistent increases in sympathetic activity and commonly develop hypertension. The objectives of this study were to determine if the persistent increases in sympathetic nerve activity, known to be induced by acute intermittent hypoxia (AIH), are mediated through activation of the pituitary adenylate cyclase activating polypeptide (PACAP) signaling system. Here, we show that the excitatory neuropeptide PACAP, acting in the spinal cord, is important for generating the sympathetic response seen following AIH. Using PACAP receptor knockout mice, and pharmacological agents in Sprague Dawley rats, we measured blood pressure, heart rate, pH, PaCO2, and splanchnic sympathetic nerve activity, under anaesthesia, to demonstrate that the sympathetic response to AIH is mediated via the PAC1 receptor, in a cAMP-dependent manner. We also report that both intermittent microinjection of glutamate into the rostroventrolateral medulla (RVLM) and intermittent infusion of a sub-threshold dose of PACAP into the subarachnoid space can mimic the sympathetic response to AIH. All the sympathetic responses are independent of blood pressure, pH or PaCO2 changes. Our results show that in AIH, PACAP signaling in the spinal cord helps drive persistent increases in sympathetic nerve activity. This mechanism may be a precursor to the development of hypertension in conditions of chronic intermittent hypoxia, such as OSA.
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Affiliation(s)
- Melissa M J Farnham
- The Heart Research Institute, Newtown, NSW, Australia.,Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | | | - Edward T O'Connor
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Polina E Nedoboy
- The Heart Research Institute, Newtown, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Bowen Dempsey
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia
| | - Suja Mohammed
- The Heart Research Institute, Newtown, NSW, Australia.,Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
| | - Angelina Y Fong
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia.,Department of Physiology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - Mandy S Y Lung
- Faculty of Medicine, Macquarie University, North Ryde, NSW, Australia
| | - Fatemeh Derakhshan
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Richard J A Wilson
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Paul M Pilowsky
- The Heart Research Institute, Newtown, NSW, Australia.,Department of Physiology, Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
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Elliot-Portal E, Laouafa S, Arias-Reyes C, Janes TA, Joseph V, Soliz J. Brain-derived erythropoietin protects from intermittent hypoxia-induced cardiorespiratory dysfunction and oxidative stress in mice. Sleep 2018; 41:4985474. [PMID: 29697839 PMCID: PMC6047438 DOI: 10.1093/sleep/zsy072] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/21/2018] [Indexed: 12/21/2022] Open
Abstract
Study Objectives Based on the fact that erythropoietin (Epo) administration in rodents protects against spatial learning and cognitive deficits induced by chronic intermittent hypoxia (CIH)-mediated oxidative damage, here we tested the hypothesis that Epo in the brain protects against cardiorespiratory disorders and oxidative stress induced by CIH in adult mice. Methods Adult control and transgenic mice overexpressing Epo in the brain only (Tg21) were exposed to CIH (21%-10% O2-10 cycles/hour-8 hours/day-7 days) or room air. After CIH exposure, we used the tail cuff method to measure arterial pressure, and whole-body plethysmography to assess the frequency of apneic episodes at rest, minute ventilation, and ventilatory responses to hypoxia and hypercapnia. Finally, the activity of pro-oxidant (XO-xanthine oxidase, and NADPH) and antioxidant (super oxide dismutase) enzymes was evaluated in the cerebral cortex and brainstem. Results Exposure of control mice to CIH significantly increased the heart rate and arterial pressure, the number of apneic events, and the ventilatory response to hypoxia and hypercapnia. Furthermore, CIH increased the ratio of pro-oxidant to antioxidant enzymes in cortex and brainstem tissues. Both physiological and molecular changes induced by CIH were prevented in transgenic Tg21 mice. Conclusions We conclude that the neuroprotective effect of Epo prevents oxidative damage in the brain and cardiorespiratory disorders induced by CIH. Considering that Epo is used in clinics to treat chronic kidney disease and stroke, our data show convincing evidence suggesting that Epo may be a promising alternative drug to treat sleep-disorder breathing.
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Affiliation(s)
- Elizabeth Elliot-Portal
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Sofien Laouafa
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Christian Arias-Reyes
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Tara Adele Janes
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Vincent Joseph
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
| | - Jorge Soliz
- Centre de Recherche de l’Institut Universitaire, de Cardiologie et de Pneumologie de Québec, Université Laval, Québec City, Québec, Canada
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Oliveira LM, Moreira TS, Takakura AC. Raphe Pallidus is Not Important to Central Chemoreception in a Rat Model of Parkinson’s Disease. Neuroscience 2018; 369:350-62. [DOI: 10.1016/j.neuroscience.2017.11.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 01/31/2023]
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Li T, Hu J, Gao F, Du X, Chen Y, Wu Q. Transcription factors regulate GPR91-mediated expression of VEGF in hypoxia-induced retinopathy. Sci Rep 2017; 7:45807. [PMID: 28374767 DOI: 10.1038/srep45807] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/03/2016] [Indexed: 12/28/2022] Open
Abstract
Hypoxia is the most important factor in the pathogenesis of diabetic retinopathy (DR). Our previous studies demonstrated that G protein-coupled receptor 91(GPR91) participated in the regulation of vascular endothelial growth factor (VEGF) secretion in DR. The present study induced OIR model in newborn rats using exposure to alternating 24-hour episodes of 50% and 12% oxygen for 14 days. Treatment with GPR91 shRNA attenuated the retinal avascular area, abnormal neovascularization and pericyte loss. Western blot and qRT-PCR demonstrated that CoCl2 exposure promoted VEGF expression and secretion, activated the ERK1/2 signaling pathways and upregulated C/EBP and AP-1. Knockdown of GPR91 inhibited ERK1/2 activity. GPR91 siRNA transduction and the ERK1/2 inhibitor U0126 inhibited the increases in C/EBP β, C/EBP δ, c-Fos and HIF-1α. Luciferase reporter assays and a chromatin immunoprecipitation (ChIP) assay demonstrated that C/EBP β and c-Fos bound the functional transcriptional factor binding site in the region of the VEGF promoter, but not C/EBP δ. Knockdown of C/EBP β and c-Fos using RNAi reduced VEGF expression. Our data suggest that activation of the GPR91-ERK1/2-C/EBP β (c-Fos, HIF-1α) signaling pathway plays a tonic role in regulating VEGF transcription in rat retinal ganglion cells.
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Wu X, Lu H, Hu L, Gong W, Wang J, Fu C, Liu Z, Li S. Chronic intermittent hypoxia affects endogenous serotonergic inputs and expression of synaptic proteins in rat hypoglossal nucleus. Am J Transl Res 2017; 9:546-557. [PMID: 28337282 PMCID: PMC5340689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/22/2017] [Indexed: 06/06/2023]
Abstract
Evidence has shown that hypoxic episodes elicit hypoglossal neuroplasticity which depends on elevated serotonin (5-HT), in contrast to the rationale of obstructive sleep apnea (OSA) that deficient serotonergic input to HMs fails to keep airway patency. Therefore, understanding of the 5-HT dynamic changes at hypoglossal nucleus (HN) during chronic intermittent hypoxia (CIH) will be essential to central pathogenic mechanism and pharmacological therapy of OSA. Moreover, the effect of CIH on BDNF-TrkB signaling proteins was quantified in an attempt to elucidate cellular cascades/synaptic mechanisms following 5-HT alteration. Male rats were randomly exposed to normal air (control), intermittent hypoxia of 3 weeks (IH3) and 5 weeks (IH5) groups. Through electrical stimulation of dorsal raphe nuclei (DRN), we conducted amperometric technique with carbon fiber electrode in vivo to measure the real time release of 5-HT at XII nucleus. 5-HT2A receptors immunostaining measured by intensity and c-Fos quantified visually were both determined by immunohistochemistry. CIH significantly reduced endogenous serotonergic inputs from DRN to XII nucleus, shown as decreased peak value of 5-HT signals both in IH3 and IH5groups, whereas time to peak and half-life period of 5-HT were unaffected. Neither 5-HT2A receptors nor c-Fos expression in HN were significantly altered by CIH. Except for marked increase in phosphorylation of ERK in IH5 rats, BDNF-TrkB signaling and synaptophys consistently demonstrated downregulated levels. These results suggest that the deficiency of 5-HT and BDNF-dependent synaptic proteins in our CIH protocol contribute to the decompensated mechanism of OSA.
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Affiliation(s)
- Xu Wu
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
- Clinical Center for Sleep Breathing Disorder and Snoring, Zhongshan Hospital, Fudan UniversityShanghai 200032, China
| | - Huan Lu
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
- Clinical Center for Sleep Breathing Disorder and Snoring, Zhongshan Hospital, Fudan UniversityShanghai 200032, China
| | - Lijuan Hu
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
| | - Wankun Gong
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology, Institutes of Brain Research, Shanghai Medical College of Fudan UniversityShanghai 200032, China
| | - Juan Wang
- Department of Pharmacology, State Key Laboratory of Medical Neurobiology, Institutes of Brain Research, Shanghai Medical College of Fudan UniversityShanghai 200032, China
| | - Cuiping Fu
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
- Clinical Center for Sleep Breathing Disorder and Snoring, Zhongshan Hospital, Fudan UniversityShanghai 200032, China
| | - Zilong Liu
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
- Clinical Center for Sleep Breathing Disorder and Snoring, Zhongshan Hospital, Fudan UniversityShanghai 200032, China
| | - Shanqun Li
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan UniversityShanghai, China
- Clinical Center for Sleep Breathing Disorder and Snoring, Zhongshan Hospital, Fudan UniversityShanghai 200032, China
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Chan A, Li S, Lee AR, Leung J, Yip A, Bird J, Godden KE, Martinez-Gonzalez D, Rattenborg NC, Balaban E, Pompeiano M. Activation of state-regulating neurochemical systems in newborn and embryonic chicks. Neuroscience 2016; 339:219-234. [DOI: 10.1016/j.neuroscience.2016.09.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 09/14/2016] [Accepted: 09/28/2016] [Indexed: 12/22/2022]
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Landry JP, Hawkins C, Lee A, Coté A, Balaban E, Pompeiano M. Chick embryos have the same pattern of hypoxic lower-brain activation as fetal mammals. Dev Neurobiol 2015; 76:64-74. [DOI: 10.1002/dneu.22299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 04/01/2015] [Accepted: 05/06/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Jeremy P. Landry
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
| | - Connor Hawkins
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
| | - Aaron Lee
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
| | - Alexandra Coté
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
| | - Evan Balaban
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
| | - Maria Pompeiano
- Department of Psychology; McGill University; Montreal Quebec Canada H3A 1B1
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Abstract
Hypoglossal (XII) motoneurons innervate muscles of the tongue whose tonic and inspiratory modulated activity protects the upper airway from collapse in patients affected by the obstructive sleep apnea (OSA) syndrome. Both norepinephrine and serotonin provide wakefulness-related excitatory drives that maintain activity in XII motoneurons, with the noradrenergic system playing a particularly prominent role in rats. When noradrenergic and serotonergic drives are antagonized, no further decline of XII nerve activity occurs during pharmacologically induced rapid eye movement (REM) sleep-like state. This is the best evidence to date that, at least in this model, the entire REM sleep-related decline of upper airway muscle tone results from withdrawal of these two excitatory inputs. A major component of noradrenergic input to XII motoneurons originates from pontine noradrenergic neurons that have state-dependent patterns of activity, maximal during wakefulness, and minimal, or absent during REM sleep. Our data suggest that not all ventrolateral medullary catecholaminergic neurons follow this pattern, with adrenergic C1 neurons probably increasing their activity during REM sleep. When rats are subjected to chronic-intermittent hypoxia, noradrenergic drive to XII motoneurons is increased by mechanisms that include sprouting of noradrenergic terminals in the XII nucleus, and increased expression of α1-adrenoceptors; an outcome that may underlie the elevated baseline activity of upper airway muscles during wakefulness in OSA patients.
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Affiliation(s)
- Leszek Kubin
- Department of Animal Biology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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Harper RM, Kumar R, Ogren JA, Macey PM. Sleep-disordered breathing: effects on brain structure and function. Respir Physiol Neurobiol 2013; 188:383-91. [PMID: 23643610 DOI: 10.1016/j.resp.2013.04.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 04/24/2013] [Accepted: 04/25/2013] [Indexed: 01/07/2023]
Abstract
Sleep-disordered breathing is accompanied by neural injury that affects a wide range of physiological systems which include processes for sensing chemoreception and airflow, driving respiratory musculature, timing circuitry for coordination of breathing patterning, and integration of blood pressure mechanisms with respiration. The damage also occurs in regions mediating emotion and mood, as well as areas regulating memory and cognitive functioning, and appears in structures that serve significant glycemic control processes. The injured structures include brain areas involved in hormone release and action of major neurotransmitters, including those playing a role in depression. The injury is reflected in a range of structural magnetic resonance procedures, and also appears as functional distortions of evoked activity in brain areas mediating vital autonomic and breathing functions. The damage is preferentially unilateral, and includes axonal projections; the asymmetry of the injury poses unique concerns for sympathetic discharge and potential consequences for arrhythmia. Sleep-disordered breathing should be viewed as a condition that includes central nervous system injury and impaired function; the processes underlying injury remain unclear.
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Affiliation(s)
- Ronald M Harper
- Department of Neurobiology, David Geffen School of Medicine at UCLA, University of California at Los Angeles, Los Angeles, CA 90095, USA; Brain Research Institute, University of California at Los Angeles, Los Angeles, CA 90095, USA.
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