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Wang N, Peng YJ, Kang W, Hildreth M, Prabhakar NR, Nanduri J. Transcriptomic Analysis of Postnatal Rat Carotid Body Development. Genes (Basel) 2024; 15:302. [PMID: 38540361 PMCID: PMC10970570 DOI: 10.3390/genes15030302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 06/14/2024] Open
Abstract
The carotid body (CB), located bilaterally at the carotid artery bifurcations, is the primary sensory organ for monitoring arterial blood O2 levels. Carotid bodies are immature at birth, exhibiting low sensitivity to hypoxia, and become more sensitive with maturation during the first few weeks of neonatal life. To understand the molecular basis for the postnatal developmental hypoxic responses of CB, we isolated CBs from 5-day and 21-day-old Sprague-Dawley rats and performed RNA sequencing, which allows comprehensive analysis of gene expression. Differentially expressed genes (DEGs) were generated using Edge R, while functional enrichment analysis was performed using gene-set enrichment analysis (GSEA). Analysis of RNA-Seq data showed 2604 DEGs of the total 12,696 genes shared between neonates and adults. Of the 2604 DEGs, 924 genes were upregulated, and 1680 genes were downregulated. Further analysis showed that genes related to oxidative phosphorylation (Ox/phos) and hypoxia-signaling pathways were significantly upregulated in neonatal CBs compared to adult CBs, suggesting a possible link to differential developmental hypoxic responses seen in CB. Genes related to cytokine signaling (INFγ and TNFα) and transcription factors (CREB and NFΚB) mediated pathways were enriched in adult CBs, suggesting that expression of these pathways may be linked to developmental regulation. The RNA-Seq results were verified by analyzing mRNA changes in selected genes by qRT-PCR. Our results of enrichment analysis of biological pathways offer valuable insight into CB hypoxic sensing responses related to the development process.
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Affiliation(s)
- Ning Wang
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, The University of Chicago, Chicago, IL 60637, USA
| | - Ying-Jie Peng
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, The University of Chicago, Chicago, IL 60637, USA
| | - Wenjun Kang
- Center for Research Informatics, The University of Chicago, Chicago, IL 60637, USA
| | - Matthew Hildreth
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, The University of Chicago, Chicago, IL 60637, USA
| | - Nanduri R. Prabhakar
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, The University of Chicago, Chicago, IL 60637, USA
| | - Jayasri Nanduri
- Institute for Integrative Physiology and Center for Systems Biology of O2 Sensing, The University of Chicago, Chicago, IL 60637, USA
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Wang C, He J, Chen C, Luo W, Dang X, Mao L. A potential role of human esophageal cancer-related gene-4 in cardiovascular homeostasis. Gene 2024; 894:147977. [PMID: 37956966 DOI: 10.1016/j.gene.2023.147977] [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: 07/19/2023] [Revised: 10/10/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023]
Abstract
Human esophageal cancer related gene-4 (ECRG-4) encodes a 148-aminoacid pre-pro-peptide that can be processed tissue-dependently into multiple small peptides possessing multiple functions distinct from, similar to, or opposite to the tumor suppressor function of the full-length Ecrg4. Ecrg-4 is covalently bound to the cell surface through its signal peptide, colocalized with the innate immunity complex (TLR4-CD14-MD2), and functions as a 'sentinel' molecule in the maintenance of epithelium and leukocyte homeostasis, meaning that the presence of Ecrg-4 on the cell surface signals the maintained homeostasis, whereas the loss of Ecrg-4 due to tissue injury activates pro-inflammatory and tissue proliferative responses, and the level of Ecrg-4 gradually returns to its pre-injury level upon wound healing. Interestingly, Ecrg-4 is also highly expressed in the heart and its conduction system, endothelial cells, and vascular smooth muscle cells. Accumulating evidence has shown that Ecrg-4 is involved in cardiac rate/rhythm control, the development of atrial fibrillation, doxorubicin-induced cardiotoxicity, the ischemic response of the heart and hypoxic response in the carotid body, the pathogenesis of atherosclerosis, and likely the endemic incidence of idiopathic dilated cardiomyopathy. These preliminary discoveries suggest that Ecrg-4 may function as a 'sentinel' molecule in cardiovascular system as well. Here, we briefly review the basic characteristics of ECRG-4 as a tumor suppressor gene and its regulatory functions on inflammation and apoptosis; summarize the discoveries about its distribution in cardiovascular system and involvement in the development of CVDs, and discuss its potential as a novel therapeutic target for the maintenance of cardiovascular system homeostasis.
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Affiliation(s)
- Chaoying Wang
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China
| | - Jianghui He
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China
| | - Chunyue Chen
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China
| | - Wenjun Luo
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China
| | - Xitong Dang
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China.
| | - Liang Mao
- The Key Laboratory of Medical Electrophysiology of Ministry of Education, Medical Electrophysiological Key Laboratory of Sichuan Province, Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Institute of Cardiovascular Research, Southwest Medical University, China; Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China.
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Abstract
The carotid body (CB) is a bilateral arterial chemoreceptor located in the carotid artery bifurcation with an essential role in cardiorespiratory homeostasis. It is composed of highly perfused cell clusters, or glomeruli, innervated by sensory fibers. Glomus cells, the most abundant in each glomerulus, are neuron-like multimodal sensory elements able to detect and integrate changes in several physical and chemical parameters of the blood, in particular O2 tension, CO2 and pH, as well as glucose, lactate, or blood flow. Activation of glomus cells (e.g., during hypoxia or hypercapnia) stimulates the afferent fibers which impinge on brainstem neurons to elicit rapid compensatory responses (hyperventilation and sympathetic activation). This chapter presents an updated view of the structural organization of the CB and the mechanisms underlying the chemosensory responses of glomus cells, with special emphasis on the molecular processes responsible for acute O2 sensing. The properties of the glomus cell-sensory fiber synapse as well as the organization of CB output are discussed. The chapter includes the description of recently discovered CB stem cells and progenitor cells, and their role in CB growth during acclimatization to hypoxemia. Finally, the participation of the CB in the mechanisms of disease is briefly discussed.
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Affiliation(s)
- José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Sevilla, Seville, Spain; Biomedical Research Center for Neurodegenerative Diseases (CIBERNED), Madrid, Spain.
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Matlac DM, Hadrava Vanova K, Bechmann N, Richter S, Folberth J, Ghayee HK, Ge GB, Abunimer L, Wesley R, Aherrahrou R, Dona M, Martínez-Montes ÁM, Calsina B, Merino MJ, Schwaninger M, Deen PMT, Zhuang Z, Neuzil J, Pacak K, Lehnert H, Fliedner SMJ. Succinate Mediates Tumorigenic Effects via Succinate Receptor 1: Potential for New Targeted Treatment Strategies in Succinate Dehydrogenase Deficient Paragangliomas. Front Endocrinol (Lausanne) 2021; 12:589451. [PMID: 33776908 PMCID: PMC7994772 DOI: 10.3389/fendo.2021.589451] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 01/29/2021] [Indexed: 12/12/2022] Open
Abstract
Paragangliomas and pheochromocytomas (PPGLs) are chromaffin tumors associated with severe catecholamine-induced morbidities. Surgical removal is often curative. However, complete resection may not be an option for patients with succinate dehydrogenase subunit A-D (SDHx) mutations. SDHx mutations are associated with a high risk for multiple recurrent, and metastatic PPGLs. Treatment options in these cases are limited and prognosis is dismal once metastases are present. Identification of new therapeutic targets and candidate drugs is thus urgently needed. Previously, we showed elevated expression of succinate receptor 1 (SUCNR1) in SDHB PPGLs and SDHD head and neck paragangliomas. Its ligand succinate has been reported to accumulate due to SDHx mutations. We thus hypothesize that autocrine stimulation of SUCNR1 plays a role in the pathogenesis of SDHx mutation-derived PPGLs. We confirmed elevated SUCNR1 expression in SDHx PPGLs and after SDHB knockout in progenitor cells derived from a human pheochromocytoma (hPheo1). Succinate significantly increased viability of SUCNR1-transfected PC12 and ERK pathway signaling compared to control cells. Candidate SUCNR1 inhibitors successfully reversed proliferative effects of succinate. Our data reveal an unrecognized oncometabolic function of succinate in SDHx PPGLs, providing a growth advantage via SUCNR1.
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Affiliation(s)
- Dieter M. Matlac
- Neuroendocrine Oncology and Metabolism, Medical Department I, Center of Brain, Behavior, and Metabolism, University Medical Center Schleswig-Holstein Lübeck, Lübeck, Germany
| | - Katerina Hadrava Vanova
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czechia
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Nicole Bechmann
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Carl Gustav Carus, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Susan Richter
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Carl Gustav Carus, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Julica Folberth
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | - Hans K. Ghayee
- Department of Medicine, Division of Endocrinology, University of Florida and Malcom Randall VA Medical Center, Gainesville, FL, United States
| | - Guang-Bo Ge
- Institute of Interdisciplinary Integrative Medicine Research, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Luma Abunimer
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | | | - Redouane Aherrahrou
- Institute for Cardiogenetics, University of Lübeck, Lübeck, Germany
- Department of Biomedical Engineering, Centre for Public Health Genomics, University of Virginia, Charlottesville, VA, United States
| | - Margo Dona
- Division of Endocrinology 471, Department of Internal Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Ángel M. Martínez-Montes
- Hereditary Endocrine Cancer Group, Human Cancer Genetics Program, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Bruna Calsina
- Hereditary Endocrine Cancer Group, Human Cancer Genetics Program, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Maria J. Merino
- Laboratory of Surgical Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Markus Schwaninger
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
| | | | - Zhengping Zhuang
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, United States
| | - Jiri Neuzil
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czechia
- School of Medical Science, Griffith University, Southport, QLD, Australia
| | - Karel Pacak
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Hendrik Lehnert
- Neuroendocrine Oncology and Metabolism, Medical Department I, Center of Brain, Behavior, and Metabolism, University Medical Center Schleswig-Holstein Lübeck, Lübeck, Germany
| | - Stephanie M. J. Fliedner
- Neuroendocrine Oncology and Metabolism, Medical Department I, Center of Brain, Behavior, and Metabolism, University Medical Center Schleswig-Holstein Lübeck, Lübeck, Germany
- *Correspondence: Stephanie M. J. Fliedner,
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Stocco E, Barbon S, Tortorella C, Macchi V, De Caro R, Porzionato A. Growth Factors in the Carotid Body-An Update. Int J Mol Sci 2020; 21:ijms21197267. [PMID: 33019660 PMCID: PMC7594035 DOI: 10.3390/ijms21197267] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 09/27/2020] [Accepted: 09/27/2020] [Indexed: 12/19/2022] Open
Abstract
The carotid body may undergo plasticity changes during development/ageing and in response to environmental (hypoxia and hyperoxia), metabolic, and inflammatory stimuli. The different cell types of the carotid body express a wide series of growth factors and corresponding receptors, which play a role in the modulation of carotid body function and plasticity. In particular, type I cells express nerve growth factor, brain-derived neurotrophic factor, neurotrophin 3, glial cell line-derived neurotrophic factor, ciliary neurotrophic factor, insulin-like-growth factor-I and -II, basic fibroblast growth factor, epidermal growth factor, transforming growth factor-α and -β, interleukin-1β and -6, tumor necrosis factor-α, vascular endothelial growth factor, and endothelin-1. Many specific growth factor receptors have been identified in type I cells, indicating autocrine/paracrine effects. Type II cells may also produce growth factors and express corresponding receptors. Future research will have to consider growth factors in further experimental models of cardiovascular, metabolic, and inflammatory diseases and in human (normal and pathologic) samples. From a methodological point of view, microarray and/or proteomic approaches would permit contemporary analyses of large groups of growth factors. The eventual identification of physical interactions between receptors of different growth factors and/or neuromodulators could also add insights regarding functional interactions between different trophic mechanisms.
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Mkrtchian S, Kåhlin J, Gómez-Galán M, Ebberyd A, Yoshitake T, Schmidt S, Kehr J, Hildenborg M, Jonsson Fagerlund M, Erlandsson Harris H, Eriksson LI. The impact of damage-associated molecular patterns on the neurotransmitter release and gene expression in the ex vivo rat carotid body. Exp Physiol 2020; 105:1634-1647. [PMID: 32652583 DOI: 10.1113/ep088705] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/08/2020] [Indexed: 12/21/2022]
Abstract
NEW FINDINGS What is the central question of this study? Are carotid bodies (CBs) modulated by the damage-associated molecular patterns (DAMPs) and humoral factors of aseptic tissue injury? What are the main findings and their importance? DAMPs (HMGB1, S100 A8/A9) and blood plasma from rats subjected to tibia surgery, a model of aseptic injury, stimulate the release of neurotransmitters (ATP, dopamine) and TNF-α from ex vivo rat CBs. All-thiol HMGB1 mediates upregulation of immune-related biological pathways. These data suggest regulation of CB function by endogenous mediators of innate immunity. ABSTRACT The glomus cells of carotid bodies (CBs) are the primary sensors of arterial partial O2 and CO2 tensions and moreover serve as multimodal receptors responding also to other stimuli, such as pathogen-associated molecular patterns (PAMPs) produced by acute infection. Modulation of CB function by excessive amounts of these immunomodulators is suggested to be associated with a detrimental hyperinflammatory state. We have hypothesized that yet another class of immunomodulators, endogenous danger-associated molecular patterns (DAMPs), released upon aseptic tissue injury and recognized by the same pathogen recognition receptors as PAMPs, might modulate the CB activity in a fashion similar to PAMPs. We have tested this hypothesis by exposing rat CBs to various DAMPs, such as HMGB1 (all-thiol and disulfide forms) and S100 A8/A9 in a series of ex vivo experiments that demonstrated the release of dopamine and ATP, neurotransmitters known to mediate CB homeostatic responses. We observed a similar response after incubating CBs with conditioned blood plasma obtained from the rats subjected to tibia surgery, a model of aseptic injury. In addition, we have investigated global gene expression in the rat CB using an RNA sequencing approach. Differential gene expression analysis showed all-thiol HMGB1-driven upregulation of a number of prominent pro-inflammatory markers including Il1α and Il1β. Interestingly, conditioned plasma had a more profound effect on the CB transcriptome resulting in inhibition rather than activation of the immune-related pathways. These data are the first to suggest potential modulation of CB function by endogenous mediators of innate immunity.
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Affiliation(s)
- Souren Mkrtchian
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Jessica Kåhlin
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden.,Function Perioperative Medicine and Intensive Care, Karolinska University Hospital and Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Marta Gómez-Galán
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Anette Ebberyd
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Takashi Yoshitake
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | | | - Jan Kehr
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Pronexus Analytical AB, Bromma, Sweden
| | - Malin Hildenborg
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden.,Function Perioperative Medicine and Intensive Care, Karolinska University Hospital and Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Malin Jonsson Fagerlund
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden.,Function Perioperative Medicine and Intensive Care, Karolinska University Hospital and Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Helena Erlandsson Harris
- Department of Medicine Solna, Section for Rheumatology, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Lars I Eriksson
- Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet, Stockholm, Sweden.,Function Perioperative Medicine and Intensive Care, Karolinska University Hospital and Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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Shin MK, Eraso CC, Mu YP, Gu C, Yeung BHY, Kim LJ, Liu XR, Wu ZJ, Paudel O, Pichard LE, Shirahata M, Tang WY, Sham JSK, Polotsky VY. Leptin Induces Hypertension Acting on Transient Receptor Potential Melastatin 7 Channel in the Carotid Body. Circ Res 2019; 125:989-1002. [PMID: 31545149 PMCID: PMC6842127 DOI: 10.1161/circresaha.119.315338] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
RATIONALE Obesity leads to resistant hypertension and mechanisms are poorly understood, but high plasma levels of leptin have been implicated. Leptin increases blood pressure acting both centrally in the dorsomedial hypothalamus and peripherally. Sites of the peripheral hypertensive effect of leptin have not been identified. We previously reported that leptin enhanced activity of the carotid sinus nerve, which transmits chemosensory input from the carotid bodies (CBs) to the medullary centers, and this effect was abolished by nonselective blockers of Trp (transient receptor potential) channels. We searched our mouse CB transcriptome database and found that the Trpm7 (transient receptor potential melastatin 7) channel was the most abundant Trp channel. OBJECTIVE To examine if leptin induces hypertension acting on the CB Trpm7. METHODS AND RESULTS C57BL/6J (n=79), leptin receptor (LepRb) deficient db/db mice (n=22), and LepRb-EGFP (n=4) mice were used. CB Trpm7 and LepRb gene expression was determined and immunohistochemistry was performed; CB glomus cells were isolated and Trpm7-like current was recorded. Blood pressure was recorded continuously in (1) leptin-treated C57BL/6J mice with intact and denervated CB; (2) leptin-treated C57BL/6J mice, which also received a nonselective Trpm7 blocker FTY720 administered systemically or topically to the CB area; (3) leptin-treated C57BL/6J mice transfected with Trpm7 small hairpin RNA to the CB, and (4) Leprb deficient obese db/db mice before and after Leprb expression in CB. Leptin receptor and Trpm7 colocalized in the CB glomus cells. Leptin induced a nonselective cation current in these cells, which was inhibited by Trpm7 blockers. Leptin induced hypertension in C57BL/6J mice, which was abolished by CB denervation, Trpm 7 blockers, and Trpm7 small hairpin RNA applied to CBs. Leprb overexpression in CB of Leprb-deficient db/db mice demethylated the Trpm7 promoter, increased Trpm7 gene expression, and induced hypertension. CONCLUSIONS We conclude that leptin induces hypertension acting on Trmp7 in CB, which opens horizons for new therapy.
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Affiliation(s)
- Mi-Kyung Shin
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
| | - Candela Caballero Eraso
- Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Hospital Universitario Virgen del Rocío/Universidad de Sevilla, Spain (C.C.E.)
| | - Yun-Ping Mu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China (Y.-P.M., X.-R.L., Z.-J.W.)
| | - Chenjuan Gu
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
| | - Bonnie H Y Yeung
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
| | - Lenise J Kim
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
- Departamento de Psicobiologia, Universidade Federal de São Paulo, Brazil (L.J.K.)
| | - Xiao-Ru Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China (Y.-P.M., X.-R.L., Z.-J.W.)
| | - Zhi-Juan Wu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China (Y.-P.M., X.-R.L., Z.-J.W.)
| | - Omkar Paudel
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (O.P., L.E.P., M.S.)
| | - Luis E Pichard
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (O.P., L.E.P., M.S.)
| | - Machiko Shirahata
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (O.P., L.E.P., M.S.)
| | | | - James S K Sham
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
| | - Vsevolod Y Polotsky
- From the Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (M.-K.S., C.G., B.H.Y.Y., L.J.K., J.S.K.S., V.Y.P.)
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8
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Potential functions of esophageal cancer-related gene-4 in the cardiovascular system. Front Med 2019; 13:639-645. [PMID: 31468282 DOI: 10.1007/s11684-019-0701-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/21/2019] [Indexed: 02/07/2023]
Abstract
Esophageal cancer-related gene-4 (Ecrg4) is cloned from the normal epithelium of the esophagus. It is constitutively expressed in quiescent epithelial cells and downregulated during tumorigenesis, and Ecrg4 expression levels are inversely correlated with the malignant phenotype of tumor cells, validating that Ecrg4 is a real tumor suppressor gene. Unlike other tumor suppressor genes that usually encode membrane or intracellular proteins, Ecrg4 encodes a 148-amino acid pre-pro-peptide that is tethered on the cell surface in epithelial cells, specialized epithelial cells, and human leukocytes, where it can be processed tissue dependently into several small peptides upon cell activation. Ecrg4 is expressed in a wide variety of other cells/tissues, including cardiomyocytes and conduction system of the heart, the glomus cells of the carotid body, adrenal glands, choroid plexus, and leukocytes among others, where it exerts distinct functions, such as promoting/suppressing inflammation, inducing neuron senescence, stimulating the hypothalamus-pituitary-adrenal axis, maintaining the stemness of stem cells, participating in the rhythm and rate control of the heart, and possibly gauging the responsiveness of the cardiovascular system (CVS) to hypoxia, in addition to tumor suppression. Here, we briefly review the latest discoveries on Ecrg4 and its underlying molecular mechanisms as a tumor suppressor and focus on the emerging roles of Ecrg4 in the CVS.
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Gao L, Ortega-Sáenz P, López-Barneo J. Acute oxygen sensing-Role of metabolic specifications in peripheral chemoreceptor cells. Respir Physiol Neurobiol 2018; 265:100-111. [PMID: 30172779 DOI: 10.1016/j.resp.2018.08.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/17/2018] [Accepted: 08/29/2018] [Indexed: 12/30/2022]
Abstract
Acute oxygen sensing is essential for humans under hypoxic environments or pathologic conditions. This is achieved by the carotid body (CB), the key arterial chemoreceptor, along with other peripheral chemoreceptor organs, such as the adrenal medulla (AM). Although it is widely accepted that inhibition of K+ channels in the plasma membrane of CB cells during acute hypoxia results in the activation of cardiorespiratory reflexes, the molecular mechanisms by which the hypoxic signal is detected to modulate ion channel activity are not fully understood. Using conditional knockout mice lacking mitochondrial complex I (MCI) subunit NDUFS2, we have found that MCI generates reactive oxygen species and pyridine nucleotides, which signal K+ channels during acute hypoxia. Comparing the transcriptomes from CB and AM, which are O2-sensitive, with superior cervical ganglion, which is practically O2-insensitive, we have found that CB and AM contain unique metabolic gene expression profiles. The "signature metabolic profile" and their biophysical characteristics could be essential for acute O2 sensing by chemoreceptor cells.
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Affiliation(s)
- Lin Gao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
| | - Patricia Ortega-Sáenz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain; Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
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11
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Zhou T, Matsunami H. Lessons from single-cell transcriptome analysis of oxygen-sensing cells. Cell Tissue Res 2017; 372:403-415. [PMID: 28887696 DOI: 10.1007/s00441-017-2682-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2017] [Accepted: 08/07/2017] [Indexed: 12/15/2022]
Abstract
The advent of single-cell RNA-sequencing (RNA-Seq) technology has enabled transcriptome profiling of individual cells. Comprehensive gene expression analysis at the single-cell level has proven to be effective in characterizing the most fundamental aspects of cellular function and identity. This unbiased approach is revolutionary for small and/or heterogeneous tissues like oxygen-sensing cells in identifying key molecules. Here, we review the major methods of current single-cell RNA-Seq technology. We discuss how this technology has advanced the understanding of oxygen-sensing glomus cells in the carotid body and helped uncover novel oxygen-sensing cells and mechanisms in the mice olfactory system. We conclude by providing our perspective on future single-cell RNA-Seq research directed at oxygen-sensing cells.
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Affiliation(s)
- Ting Zhou
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 261 CARL Building, Box 3509, Durham, NC, USA.
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, 261 CARL Building, Box 3509, Durham, NC, USA.,Department of Neurobiology and Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
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12
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Gao L, Bonilla-Henao V, García-Flores P, Arias-Mayenco I, Ortega-Sáenz P, López-Barneo J. Gene expression analyses reveal metabolic specifications in acute O 2 -sensing chemoreceptor cells. J Physiol 2017; 595:6091-6120. [PMID: 28718507 DOI: 10.1113/jp274684] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/03/2017] [Indexed: 01/05/2023] Open
Abstract
KEY POINTS Glomus cells in the carotid body (CB) and chromaffin cells in the adrenal medulla (AM) are essential for reflex cardiorespiratory adaptation to hypoxia. However, the mechanisms whereby these cells detect changes in O2 tension are poorly understood. The metabolic properties of acute O2 -sensing cells have been investigated by comparing the transcriptomes of CB and AM cells, which are O2 -sensitive, with superior cervical ganglion neurons, which are practically O2 -insensitive. In O2 -sensitive cells, we found a characteristic prolyl hydroxylase 3 down-regulation and hypoxia inducible factor 2α up-regulation, as well as overexpression of genes coding for three atypical mitochondrial electron transport subunits and pyruvate carboxylase, an enzyme that replenishes tricarboxylic acid cycle intermediates. In agreement with this observation, the inhibition of succinate dehydrogenase impairs CB acute O2 sensing. The responsiveness of peripheral chemoreceptor cells to acute hypoxia depends on a 'signature metabolic profile'. ABSTRACT Acute O2 sensing is a fundamental property of cells in the peripheral chemoreceptors, e.g. glomus cells in the carotid body (CB) and chromaffin cells in the adrenal medulla (AM), and is necessary for adaptation to hypoxia. These cells contain O2 -sensitive ion channels, which mediate membrane depolarization and transmitter release upon exposure to hypoxia. However, the mechanisms underlying the detection of changes in O2 tension by cells are still poorly understood. Recently, we suggested that CB glomus cells have specific metabolic features that favour the accumulation of reduced quinone and the production of mitochondrial NADH and reactive oxygen species during hypoxia. These signals alter membrane ion channel activity. To investigate the metabolic profile characteristic of acute O2 -sensing cells, we used adult mice to compare the transcriptomes of three cell types derived from common sympathoadrenal progenitors, but exhibiting variable responsiveness to acute hypoxia: CB and AM cells, which are O2 -sensitive (glomus cells > chromaffin cells), and superior cervical ganglion neurons, which are practically O2 -insensitive. In the O2 -sensitive cells, we found a characteristic mRNA expression pattern of prolyl hydroxylase 3/hypoxia inducible factor 2α and up-regulation of several genes, in particular three atypical mitochondrial electron transport subunits and some ion channels. In addition, we found that pyruvate carboxylase, an enzyme fundamental to tricarboxylic acid cycle anaplerosis, is overexpressed in CB glomus cells. We also observed that the inhibition of succinate dehydrogenase impairs CB acute O2 sensing. Our data suggest that responsiveness to acute hypoxia depends on a 'signature metabolic profile' in chemoreceptor cells.
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Affiliation(s)
- Lin Gao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Victoria Bonilla-Henao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Paula García-Flores
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Ignacio Arias-Mayenco
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Patricia Ortega-Sáenz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
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13
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Zhou T, Chien MS, Kaleem S, Matsunami H. Single cell transcriptome analysis of mouse carotid body glomus cells. J Physiol 2016; 594:4225-51. [PMID: 26940531 DOI: 10.1113/jp271936] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 02/24/2016] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS Carotid body (CB) glomus cells mediate acute oxygen sensing and the initiation of the hypoxic ventilatory response, yet the gene expression profile of these cells is not available. We demonstrate that the single cell RNA-Seq method is a powerful tool for identifying highly expressed genes in CB glomus cells. Our single cell RNA-Seq results characterized novel CB glomus cell genes, including members of the G protein-coupled receptor signalling pathway, ion channels and atypical mitochondrial electron transport chain subunits. A heterologous cell-based screening identified acetate (which is known to affect CB glomus cell activity) as an agonist for the most highly abundant G protein-coupled receptor (Olfr78) in CB glomus cells. These data established the first transcriptome profile of CB glomus cells, highlighting genes with potential implications in CB chemosensory function. ABSTRACT The carotid body (CB) is a major arterial chemoreceptor containing glomus cells whose activities are regulated by changes in arterial blood content, including oxygen. Despite significant advancements in the characterization of their physiological properties, our understanding of the underlying molecular machinery and signalling pathway in CB glomus cells is still limited. To overcome this, we employed the single cell RNA-Seq method by performing next-generation sequencing on single glomus cell-derived cDNAs to eliminate contamination of genes derived from other cell types present in the CB. Using this method, we identified a set of genes abundantly expressed in glomus cells, which contained novel glomus cell-specific genes. Transcriptome and subsequent in situ hybridization and immunohistochemistry analyses identified abundant G protein-coupled receptor signalling pathway components and various types of ion channels, as well as members of the hypoxia-inducible factors pathway. A short-chain fatty acid olfactory receptor Olfr78, recently implicated in CB function, was the most abundant G protein-coupled receptor. Two atypical mitochondrial electron transport chain subunits (Ndufa4l2 and Cox4i2) were among the most specifically expressed genes in CB glomus cells, highlighting their potential roles in mitochondria-mediated oxygen sensing. The wealth of information provided by the present study offers a valuable foundation for identifying molecules functioning in the CB.
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Affiliation(s)
- Ting Zhou
- Department of Molecular Genetics and Microbiology, Duke University Medical Centre, Durham, NC, USA
| | - Ming-Shan Chien
- Department of Molecular Genetics and Microbiology, Duke University Medical Centre, Durham, NC, USA
| | - Safa Kaleem
- Department of Molecular Genetics and Microbiology, Duke University Medical Centre, Durham, NC, USA
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University Medical Centre, Durham, NC, USA.,Department of Neurobiology and Duke Institute for Brain Sciences, Duke University, Durham, NC, USA
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14
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Hodson EJ, Nicholls LG, Turner PJ, Llyr R, Fielding JW, Douglas G, Ratnayaka I, Robbins PA, Pugh CW, Buckler KJ, Ratcliffe PJ, Bishop T. Regulation of ventilatory sensitivity and carotid body proliferation in hypoxia by the PHD2/HIF-2 pathway. J Physiol 2016; 594:1179-95. [PMID: 26337139 PMCID: PMC4771794 DOI: 10.1113/jp271050] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/26/2015] [Indexed: 12/24/2022] Open
Abstract
Ventilatory sensitivity to hypoxia increases in response to continued hypoxic exposure as part of acute acclimatisation. Although this process is incompletely understood, insights have been gained through studies of the hypoxia-inducible factor (HIF) hydroxylase system. Genetic studies implicate these pathways widely in the integrated physiology of hypoxia, through effects on developmental or adaptive processes. In keeping with this, mice that are heterozygous for the principal HIF prolyl hydroxylase, PHD2, show enhanced ventilatory sensitivity to hypoxia and carotid body hyperplasia. Here we have sought to understand this process better through comparative analysis of inducible and constitutive inactivation of PHD2 and its principal targets HIF-1α and HIF-2α. We demonstrate that general inducible inactivation of PHD2 in tamoxifen-treated Phd2(f/f);Rosa26(+/CreERT2) mice, like constitutive, heterozygous PHD2 deficiency, enhances hypoxic ventilatory responses (HVRs: 7.2 ± 0.6 vs. 4.4 ± 0.4 ml min(-1) g(-1) in controls, P < 0.01). The ventilatory phenotypes associated with both inducible and constitutive inactivation of PHD2 were strongly compensated for by concomitant inactivation of HIF-2α, but not HIF-1α. Furthermore, inducible inactivation of HIF-2α strikingly impaired ventilatory acclimatisation to chronic hypoxia (HVRs: 4.1 ± 0.5 vs. 8.6 ± 0.5 ml min(-1) g(-1) in controls, P < 0.0001), as well as carotid body cell proliferation (400 ± 81 vs. 2630 ± 390 bromodeoxyuridine-positive cells mm(-2) in controls, P < 0.0001). The findings demonstrate the importance of the PHD2/HIF-2α enzyme-substrate couple in modulating ventilatory sensitivity to hypoxia.
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Affiliation(s)
- Emma J Hodson
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
| | - Lynn G Nicholls
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
| | - Philip J Turner
- Department of Physiology, Anatomy and Genetics, Sherrington Building, South Parks Road, University of Oxford, Oxford, OX1 3PT, UK
| | - Ronan Llyr
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
| | - James W Fielding
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
- Ludwig Institute for Cancer Research, Roosevelt Drive, University of Oxford, Oxford, OX3 7DQ, UK
| | - Gillian Douglas
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
| | - Indrika Ratnayaka
- Ludwig Institute for Cancer Research, Roosevelt Drive, University of Oxford, Oxford, OX3 7DQ, UK
| | - Peter A Robbins
- Department of Physiology, Anatomy and Genetics, Sherrington Building, South Parks Road, University of Oxford, Oxford, OX1 3PT, UK
| | - Christopher W Pugh
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
| | - Keith J Buckler
- Department of Physiology, Anatomy and Genetics, Sherrington Building, South Parks Road, University of Oxford, Oxford, OX1 3PT, UK
| | - Peter J Ratcliffe
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
- Ludwig Institute for Cancer Research, Roosevelt Drive, University of Oxford, Oxford, OX3 7DQ, UK
| | - Tammie Bishop
- Wellcome Trust Centre for Human Genetics, Roosevelt Drive, University of Oxford, Oxford, OX3 7BN, UK
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15
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Chang AJ, Ortega FE, Riegler J, Madison DV, Krasnow MA. Oxygen regulation of breathing through an olfactory receptor activated by lactate. Nature 2015; 527:240-4. [PMID: 26560302 PMCID: PMC4765808 DOI: 10.1038/nature15721] [Citation(s) in RCA: 200] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/28/2015] [Indexed: 12/25/2022]
Abstract
Animals have evolved homeostatic responses to changes in oxygen availability that act on different time scales. Although the hypoxia-inducible factor (HIF) transcriptional pathway that controls long term responses to low oxygen (hypoxia) has been established1, the pathway that mediates acute responses to hypoxia in mammals is not well understood. Here we show that the olfactory receptor Olfr78 is highly and selectively expressed in oxygen-sensitive glomus cells of the carotid body, a chemosensory organ at the carotid artery bifurcation that monitors blood oxygen and stimulates breathing within seconds when oxygen declines2. Olfr78 mutants fail to increase ventilation in hypoxia but respond normally to hypercapnia. Glomus cells are present in normal numbers and appear structurally intact, but hypoxia-induced carotid body activity is diminished. Lactate, a metabolite that rapidly accumulates in hypoxia and induces hyperventilation3–6, activates Olfr78 in heterologous expression experiments, induces calcium transients in glomus cells, and stimulates carotid sinus nerve activity through Olfr78. We propose that in addition to its role in olfaction, Olfr78 acts as a hypoxia sensor in the breathing circuit by sensing lactate produced when oxygen levels decline.
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Affiliation(s)
- Andy J Chang
- Department of Biochemistry, Stanford University School of Medicine and Howard Hughes Medical Institute, Stanford, California 94305-5307, USA
| | - Fabian E Ortega
- Department of Biochemistry, Stanford University School of Medicine and Howard Hughes Medical Institute, Stanford, California 94305-5307, USA
| | - Johannes Riegler
- Department of Medicine, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Daniel V Madison
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Mark A Krasnow
- Department of Biochemistry, Stanford University School of Medicine and Howard Hughes Medical Institute, Stanford, California 94305-5307, USA
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16
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Kåhlin J, Mkrtchian S, Ebberyd A, Eriksson LI, Fagerlund MJ. The Human Carotid Body Gene Expression and Function in Signaling of Hypoxia and Inflammation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 860:371-7. [DOI: 10.1007/978-3-319-18440-1_42] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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17
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Role of BK Channels in Murine Carotid Body Neural Responses in vivo. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 860:325-33. [PMID: 26303497 DOI: 10.1007/978-3-319-18440-1_37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The aim of this study was to explore the role of BK channels in the hypoxic sensitivity of the in vivo murine carotid body (CB). Four strains of mice (DBA/2J, A/J, BKα1 knockout and BKα1 wild type - FVB background) were used. The mice were anesthetized, paralyzed and mechanically ventilated (PaCO(2) ~ 35 mmHg, PO(2) > 300 mmHg). We measured carotid sinus nerve (CSN) activity during three gas challenges (F(I)O(2): 0.21, 0.15 and 0.10). CSN activity was analyzed with time-variant spectral analysis with frequency domain conversion (Fast Fourier Transforms). Afferent CSN activity increased with lowering F(I)O(2) in the DBA/2J, BKKO and BKWT mice with the most robust response in 600-800 frequencies. No substantial changes were observed in the A/J mice. Although maximal neural output was similar between the BKKO and BKWT mice, the BKWT had a higher early response compared to BKKO. Thus, BK channels may play a role in the initial response of the CB to hypoxia. The contribution of BKβ subunits or the importance of frequency specific responses was unable to be determined by the current study.
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18
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Shirahata M, Tang WY, Shin MK, Polotsky VY. Is the Carotid Body a Metabolic Monitor? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 860:153-9. [PMID: 26303477 PMCID: PMC4793901 DOI: 10.1007/978-3-319-18440-1_17] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The carotid body is a multi-modal sensor and it has been debated if it senses low glucose. We have hypothesized that the carotid body is modified by some metabolic factors other than glucose and contributes to whole body glucose metabolism. This study examined the roles of insulin, leptin and transient receptor potential (TRP) channels on carotid sinus nerve (CSN) chemoreceptor discharge. In agreement with other studies, CSN activity was not modified by low glucose. Insulin did not affect the CSN hypoxic response. Leptin significantly augmented the CSN response to hypoxia and nonspecific Trp channel blockers (SKF96365, 2-APB) reversed the effect of leptin. Gene expression analysis showed high expression of Trpm3, 6, and 7 channels in the carotid body and petrosal ganglion. The results suggest that the adult mouse carotid body does not sense glucose levels directly. The carotid body may contribute to neural control of glucose metabolism via leptin receptor-mediated TRP channel activation.
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Affiliation(s)
- M Shirahata
- Department of Environmental Health Sciences, Johns Hopkins University, Baltimore, MD, USA,
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19
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Abstract
SIGNIFICANCE Ventilatory responses to hypoxia are initiated by the carotid body, where inhibition of specific K(+) channels causes cell depolarization, voltage-gated Ca(2+) influx, and neurotransmitter release. The identity of the upstream oxygen (O2) sensor is still controversial. RECENT ADVANCES The activity of BKCa channels is regulated by O2, carbon monoxide (CO), and hydrogen sulfide (H2S), suggesting that integration of these signals may be crucial to the physiological response of this tissue. BKCa is colocalized with hemeoxygenase-2, an enzyme that generates CO in the presence of O2, and CO is a BKCa channel opener. Reduced CO during hypoxia results in channel closure, conferring a degree of O2 sensitivity to the BKCa channel. Conversely, H2S is a potent BKCa inhibitor. H2S is produced endogenously by cystathionine-β-synthase and cystathionine-γ-lyase in the rat carotid body, and its intracellular concentration is dependent upon the balance between its enzymatic generation and its mitochondrial breakdown. During hypoxia, mitochondrial oxidation of H2S in many tissues is reduced, leading to hypoxia-evoked rises in its concentration. This may be sufficient to inhibit K(+) channels and lead to carotid body excitation. CRITICAL ISSUES Carotid body function is heavily dependent upon regulated production and breakdown of CO and H2S and integration of signals from these newly emerging gasotransmitters, in combination with several other proposed mechanisms, may refine, or even define, responses of this tissue to hypoxia. FUTURE DIRECTIONS Since several other sensors have been postulated, the challenge of future research is to begin to integrate each in a unifying mechanism, as has been attempted for the first time herein.
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Affiliation(s)
- Paul J Kemp
- Division of Pathophysiology and Repair, School of Biosciences, Cardiff University , Cardiff, United Kingdom
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20
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Abstract
Among the several topics included in respiratory studies investigators have focused on the control of breathing for a relatively few number of years, perhaps only the last 75 to 80. For a very long time, the phenomenon of respiration presented a great mystery. The Chinese had suggestions for proper breathing, and later the Egyptians sought to understand its purpose. But in the western world, the early Greeks made the more significant observations. Centuries passed before the anatomical structures pertinent to respiration were properly visualized and located. There followed efforts to understand if lung movement was necessary for life and what happened in the lung. The rise of chemistry in the 18th century eventually clarified the roles of the gases significant in respiratory behavior. More time was needed to understand what gases provoked increases in breathing and where those gases worked. At this point, control of breathing became a significant focus of respiratory investigators. Studies included identifying the structures and functions of central and peripheral chemoreceptors, and airway receptors, sources of respiratory rhythm and pattern generation, the impact of the organism's status on its breathing including environment and disease/trauma. At this same time, mid- to late-20th century, efforts to mathematicize the variables in the control of breathing appeared. So though wonderment about the mysterious phenomenon of respiration began over two millennia ago, serious physiological investigation into its control is by comparison very young.
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Affiliation(s)
- Robert S Fitzgerald
- Departments of Environmental Health Sciences Division of Physiology, of Physiology, and of Medicine, The Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
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21
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Kelly SA, Rezende EL, Chappell MA, Gomes FR, Kolb EM, Malisch JL, Rhodes JS, Mitchell GS, Garland T. Exercise training effects on hypoxic and hypercapnic ventilatory responses in mice selected for increased voluntary wheel running. Exp Physiol 2013; 99:403-13. [PMID: 24142456 DOI: 10.1113/expphysiol.2013.076018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? We used experimental evolution to determine how selective breeding for high voluntary wheel running and exercise training (7-11 weeks) affect ventilatory chemoreflexes of laboratory mice at rest. What is the main finding and its importance? Selective breeding, although significantly affecting some traits, did not systematically alter ventilation across gas concentrations. As with most human studies, our findings support the idea that endurance training attenuates resting ventilation. However, little evidence was found for a correlation between ventilatory chemoreflexes and the amount of individual voluntary wheel running. We conclude that exercise 'training' alters respiratory behaviours, but these changes may not be necessary to achieve high levels of wheel running. Ventilatory control is affected by genetics, the environment and gene-environment and gene-gene interactions. Here, we used an experimental evolution approach to test whether 37 generations of selective breeding for high voluntary wheel running (genetic effects) and/or long-term (7-11 weeks) wheel access (training effects) alter acute respiratory behaviour of mice resting in normoxic, hypoxic and hypercapnic conditions. As the four replicate high-runner (HR) lines run much more than the four non-selected control (C) lines, we also examined whether the amount of exercise among individual mice was a quantitative predictor of ventilatory chemoreflexes at rest. Selective breeding and/or wheel access significantly affected several traits. In normoxia, HR mice tended to have lower mass-adjusted rates of oxygen consumption and carbon dioxide production. Chronic wheel access increased oxygen consumption and carbon dioxide production in both HR and C mice during hypercapnia. Breathing frequency and minute ventilation were significantly reduced by chronic wheel access in both HR and C mice during hypoxia. Selection history, while significantly affecting some traits, did not systematically alter ventilation across all gas concentrations. As with most human studies, our findings support the idea that endurance training (access to wheel running) attenuates resting ventilation. However, little evidence was found for a correlation at the level of the individual variation between ventilatory chemoreflexes and performance (amount of individual voluntary wheel running). We tentatively conclude that exercise 'training' alters respiratory behaviours, but these changes may not be necessary to achieve high levels of wheel running.
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Affiliation(s)
- Scott A Kelly
- * Ohio Wesleyan University, Schimmel/Conrades Science Center #346, 61 S. Sandusky Street, Delaware, OH 43015, USA.
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22
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Shirahata M, Kostuk EW, Pichard LE. Carotid chemoreceptor development in mice. Respir Physiol Neurobiol 2012; 185:20-9. [PMID: 22634368 DOI: 10.1016/j.resp.2012.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 10/28/2022]
Abstract
Mice are the most suitable species for understanding genetic aspects of postnatal developments of the carotid body due to the availability of many inbred strains and knockout mice. Our study has shown that the carotid body grows differentially in different mouse strains, indicating the involvement of genes. However, the small size hampers investigating functional development of the carotid body. Hypoxic and/or hyperoxic ventilatory responses have been investigated in newborn mice, but these responses are indirect assessment of the carotid body function. Therefore, we need to develop techniques of measuring carotid chemoreceptor neural activity from young mice. Many studies have taken advantage of the knockout mice to understand chemoreceptor function of the carotid body, but they are not always suitable for addressing postnatal development of the carotid body due to lethality during perinatal periods. Various inbred strains with well-designed experiments will provide useful information regarding genetic mechanisms of the postnatal carotid chemoreceptor development. Also, targeted gene deletion is a critical approach.
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Affiliation(s)
- Machiko Shirahata
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
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Mosqueira M, Willmann G, Zeiger U, Khurana TS. Expression profiling reveals novel hypoxic biomarkers in peripheral blood of adult mice exposed to chronic hypoxia. PLoS One 2012; 7:e37497. [PMID: 22629407 PMCID: PMC3358260 DOI: 10.1371/journal.pone.0037497] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 04/24/2012] [Indexed: 12/31/2022] Open
Abstract
Hypoxia induces a myriad of changes including an increase in hematocrit due to erythropoietin (EPO) mediated erythropoiesis. While hypoxia is of importance physiologically and clinically, lacunae exist in our knowledge of the systemic and temporal changes in gene expression occurring in blood during the exposure and recovery from hypoxia. To identify these changes expression profiling was conducted on blood obtained from cohorts of C57Bl-10 wild type mice that were maintained at normoxia (NX), exposed for two weeks to normobaric chronic hypoxia (CH) or two weeks of CH followed by two weeks of normoxic recovery (REC). Using stringent bioinformatic cut-offs (0% FDR, 2 fold change cut-off), 230 genes were identified and separated into four distinct temporal categories. Class I) contained 1 transcript up-regulated in both CH and REC; Class II) contained 202 transcripts up-regulated in CH but down-regulated after REC; Class III) contained 9 transcripts down-regulated both in CH and REC; Class IV) contained 18 transcripts down-regulated after CH exposure but up-regulated after REC. Profiling was independently validated and extended by analyzing expression levels of selected genes as novel biomarkers from our profile (e.g. spectrin alpha-1, ubiquitin domain family-1 and pyrroline-5-carboxylate reductase-1) by performing qPCR at 7 different time points during CH and REC. Our identification and characterization of these genes define transcriptome level changes occurring during chronic hypoxia and normoxic recovery as well as novel blood biomarkers that may be useful in monitoring a variety of physiological and pathological conditions associated with hypoxia.
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Affiliation(s)
- Matias Mosqueira
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
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Mkrtchian S, Kåhlin J, Ebberyd A, Gonzalez C, Sanchez D, Balbir A, Kostuk EW, Shirahata M, Fagerlund MJ, Eriksson LI. The human carotid body transcriptome with focus on oxygen sensing and inflammation--a comparative analysis. J Physiol 2012; 590:3807-19. [PMID: 22615433 DOI: 10.1113/jphysiol.2012.231084] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The carotid body (CB) is the key oxygen sensing organ. While the expression of CB specific genes is relatively well studied in animals, corresponding data for the human CB are missing. In this study we used five surgically removed human CBs to characterize the CB transcriptome with microarray and PCR analyses, and compared the results with mice data. In silico approaches demonstrated a unique gene expression profile of the human and mouse CB transcriptomes and an unexpected upregulation of both human and mouse CB genes involved in the inflammatory response compared to brain and adrenal gland data. Human CBs express most of the genes previously proposed to be involved in oxygen sensing and signalling based on animal studies, including NOX2, AMPK, CSE and oxygen sensitive K+ channels. In the TASK subfamily of K+ channels, TASK-1 is expressed in human CBs, while TASK-3 and TASK-5 are absent, although we demonstrated both TASK-1 and TASK-3 in one of the mouse reference strains. Maxi-K was expressed exclusively as the spliced variant ZERO in the human CB. In summary, the human CB transcriptome shares important features with the mouse CB, but also differs significantly in the expression of a number of CB chemosensory genes. This study provides key information for future functional investigations on the human carotid body.
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Affiliation(s)
- Souren Mkrtchian
- Section for Anesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
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25
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Wang T, Lang GD, Moreno-Vinasco L, Huang Y, Goonewardena SN, Peng YJ, Svensson EC, Natarajan V, Lang RM, Linares JD, Breysse PN, Geyh AS, Samet JM, Lussier YA, Dudley S, Prabhakar NR, Garcia JGN. Particulate matter induces cardiac arrhythmias via dysregulation of carotid body sensitivity and cardiac sodium channels. Am J Respir Cell Mol Biol 2011; 46:524-31. [PMID: 22108299 DOI: 10.1165/rcmb.2011-0213oc] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The mechanistic links between exposure to airborne particulate matter (PM) pollution and the associated increases in cardiovascular morbidity and mortality, particularly in people with congestive heart failure (CHF), have not been identified. To advance understanding of this issue, genetically engineered mice (CREB(A133)) exhibiting severe dilated cardiomyopathic changes were exposed to ambient PM collected in Baltimore. CREB(A133) mice, which display aberrant cardiac physiology and anatomy reminiscent of human CHF, displayed evidence of basal autonomic aberrancies (compared with wild-type mice) with PM exposure via aspiration, producing significantly reduced heart rate variability, respiratory dysynchrony, and increased ventricular arrhythmias. Carotid body afferent nerve responses to hypoxia and hyperoxia-induced respiratory depression were pronounced in PM-challenged CREB(A133) mice, and denervation of the carotid bodies significantly reduced PM-mediated cardiac arrhythmias. Genome-wide expression analyses of CREB(A133) left ventricular tissues demonstrated prominent Na(+) and K(+) channel pathway gene dysregulation. Subsequent PM challenge increased tyrosine phosphorylation and nitration of the voltage-gated type V cardiac muscle α-subunit of the Na(+) channel encoded by SCN5A. Ranolazine, a Na(+) channel modulator that reduces late cardiac Na(+) channel currents, attenuated PM-mediated cardiac arrhythmias and shortened PM-elongated QT intervals in vivo. These observations provide mechanistic insights into the epidemiologic findings in susceptibility of human CHF populations to PM exposure. Our results suggest a multiorgan pathobiology inherent to the CHF phenotype that is exaggerated by PM exposure via heightened carotid body sensitivity and cardiac Na(+) channel dysfunction.
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Affiliation(s)
- Ting Wang
- Section of Pulmonary, Critical Care, Sleep & Allergy, Department of Medicine, University of Illinois at Chicago, Illinois, USA
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Kostuk EW, Balbir A, Fujii K, Fujioka A, Pichard LE, Shirahata M. Divergent postnatal development of the carotid body in DBA/2J and A/J strains of mice. J Appl Physiol (1985) 2011; 112:490-500. [PMID: 22074716 DOI: 10.1152/japplphysiol.01477.2010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We have previously shown that the adult DBA/2J and A/J strains of mice differ in carotid body volume and morphology. The question has arisen whether these differences develop during the prenatal or postnatal period. Investigating morphological development of the carotid body and contributing genes in these mice can provide further understanding of the appropriate formation of the carotid body. We examined the carotid body of these mice from 1 day to 4 wk old for differences in volume, morphology, and gene expression of Gdnf family, Dlx2, Msx2, and Phox2b. The two strains showed divergent morphology starting at 1 wk old. The volume of the carotid body increased from 1 wk up to 2 wk old to the level of 4 wk old in the DBA/2J mice but not in the A/J mice. This corresponds with immunoreactivity of LC3, an autophagy marker, in A/J tissues at 10 days and 2 wk. The differences in gene expression were examined at 1 wk, 10 days, and 2 wk old, because divergent growth occurred during this period. The DBA/2J's carotid body at 1 wk old showed a greater expression of Msx2 than the A/J's carotid body. No other candidate genes showed consistent differences between the ages and strains. The difference was not seen in sympathetic cervical ganglia of 1 wk old, suggesting that the difference is carotid body specific. The current study indicates the critical postnatal period for developing distinctive morphology of the carotid body in these mice. Further studies are required to further elucidate a role of Msx2 and other uninvestigated genes.
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Affiliation(s)
- Eric W Kostuk
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA
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Fitzgerald RS, Shirahata M, Chang I, Kostuk E, Kiihl S. The impact of hydrogen sulfide (H₂S) on neurotransmitter release from the cat carotid body. Respir Physiol Neurobiol 2011; 176:80-9. [PMID: 21292043 PMCID: PMC3095827 DOI: 10.1016/j.resp.2011.01.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Revised: 01/25/2011] [Accepted: 01/26/2011] [Indexed: 12/16/2022]
Abstract
Do cat carotid bodies (CBs) increase their release of acetylcholine and ATP in response to H(2)S? Two CBs, incubated in a Krebs Ringer bicarbonate solution at 37 ° C, exhibited a normal response to hypoxia-increased release of acetylcholine (ACh) and ATP. They were challenged with several concentrations of Na(2)S, an H(2)S donor. H(2)S, a new gasotransmitter, is reported to open K(ATP) channels. Under normoxic conditions the CBs reduced their release of ACh and ATP below control values. They responded identically to pinacidil, a well-known K(ATP) channel opener. CB glomus cells exhibited a positive immunohistochemical signal for cystathione-β-synthetase, a H(2)S synthesizing enzyme, and for a subunit of the K(ATP) channel. The data suggest that Na(2)S may have opened the glomus cells' K(ATP) channels, hyperpolarizing the cells, thus reducing their tonic release of ACh and ATP. Since during hypoxia H(2)S levels rise, the glomus cells responding very actively to hypoxia may be protected from over-exertion by the H(2)S opening of the K(ATP) channels.
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Affiliation(s)
- Robert S Fitzgerald
- Department of Environmental Health Sciences (Division of Physiology), The Johns Hopkins Medical Institutions, Baltimore, MD 21205, USA.
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Teppema LJ, Dahan A. The Ventilatory Response to Hypoxia in Mammals: Mechanisms, Measurement, and Analysis. Physiol Rev 2010; 90:675-754. [DOI: 10.1152/physrev.00012.2009] [Citation(s) in RCA: 257] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The respiratory response to hypoxia in mammals develops from an inhibition of breathing movements in utero into a sustained increase in ventilation in the adult. This ventilatory response to hypoxia (HVR) in mammals is the subject of this review. The period immediately after birth contains a critical time window in which environmental factors can cause long-term changes in the structural and functional properties of the respiratory system, resulting in an altered HVR phenotype. Both neonatal chronic and chronic intermittent hypoxia, but also chronic hyperoxia, can induce such plastic changes, the nature of which depends on the time pattern and duration of the exposure (acute or chronic, episodic or not, etc.). At adult age, exposure to chronic hypoxic paradigms induces adjustments in the HVR that seem reversible when the respiratory system is fully matured. These changes are orchestrated by transcription factors of which hypoxia-inducible factor 1 has been identified as the master regulator. We discuss the mechanisms underlying the HVR and its adaptations to chronic changes in ambient oxygen concentration, with emphasis on the carotid bodies that contain oxygen sensors and initiate the response, and on the contribution of central neurotransmitters and brain stem regions. We also briefly summarize the techniques used in small animals and in humans to measure the HVR and discuss the specific difficulties encountered in its measurement and analysis.
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Affiliation(s)
- Luc J. Teppema
- Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Albert Dahan
- Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands
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Kemp PJ, Telezhkin V, Wilkinson WJ, Mears R, Hanmer SB, Gadeberg HC, Müller CT, Riccardi D, Brazier SP. Enzyme-Linked Oxygen Sensing by Potassium Channels. Ann N Y Acad Sci 2009; 1177:112-8. [DOI: 10.1111/j.1749-6632.2009.05025.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Vidal RL, Valenzuela JI, Luján R, Couve A. Cellular and subcellular localization of Marlin-1 in the brain. BMC Neurosci 2009; 10:37. [PMID: 19386132 PMCID: PMC2685396 DOI: 10.1186/1471-2202-10-37] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Accepted: 04/22/2009] [Indexed: 02/07/2023] Open
Abstract
Background Marlin-1 is a microtubule binding protein that associates specifically with the GABAB1 subunit in neurons and with members of the Janus kinase family in lymphoid cells. In addition, it binds the molecular motor kinesin-I and nucleic acids, preferentially single stranded RNA. Marlin-1 is expressed mainly in the central nervous system but little is known regarding its cellular and subcellular distribution in the brain. Results Here we have studied the localization of Marlin-1 in the rodent brain and cultured neurons combining immunohistochemistry, immunofluorescence and pre-embedding electron microscopy. We demonstrate that Marlin-1 is enriched in restricted areas of the brain including olfactory bulb, cerebral cortex, hippocampus and cerebellum. Marlin-1 is abundant in dendrites and axons of GABAergic and non-GABAergic hippocampal neurons. At the ultrastructural level, Marlin-1 is present in the cytoplasm and the nucleus of CA1 neurons in the hippocampus. In the cytoplasm it associates to microtubules in the dendritic shaft and occasionally with the Golgi apparatus, the endoplasmic reticulum (ER) and dendritic spines. In the nucleus, clusters of Marlin-1 associate to euchromatin. Conclusion Our results demonstrate that Marlin-1 is expressed in discrete areas of the brain. They also confirm the microtubule association at the ultrastructural level in neurons. Together with the abundance of the protein in dendrites and axons they are consistent with the emerging role of Marlin-1 as an intracellular protein linking the cytoskeleton and transport. Our study constitutes the first detailed description of the cellular and subcellular distribution of Marlin-1 in the brain. As such, it will set the basis for future studies on the functional implications of Marlin-1 in protein trafficking.
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Affiliation(s)
- René L Vidal
- Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Independencia, Santiago, Chile.
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Balbir A, Lande B, Fitzgerald RS, Polotsky V, Mitzner W, Shirahata M. Behavioral and respiratory characteristics during sleep in neonatal DBA/2J and A/J mice. Brain Res 2008; 1241:84-91. [PMID: 18817755 DOI: 10.1016/j.brainres.2008.09.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 09/05/2008] [Accepted: 09/08/2008] [Indexed: 11/15/2022]
Abstract
The ventilatory response to hypoxia depends on the carotid body function and sleep-wake states. Therefore, the response must be measured in a consistent sleep-wake state. In mice, EMG with behavioral indices (coordinated movements, CMs; myoclonic twitches, MTs) has been used to assess sleep-wake states. However, in neonatal mice EMG instrumentation could induce stress, altering their behavior and ventilation. Accordingly, we examined: (1) if EMG can be eliminated for assessing sleep-wake states; and (2) behavioral characteristics and carotid body-mediated respiratory control during sleep with EMG (EMG+) or without EMG (EMG-). Seven-day-old DBA/2J and A/J mice were divided into EMG+ and EMG- groups. In both strains, CMs occurred when EMG was high; MTs were present during silent/low EMG activity. The durations of high EMG activity and of CMs were statistically indifferent. Thus, CMs can be used to indicate wake state without EMG. The stress caused by EMG instrumentation may be distinctively manifested based on genetic background. Prolonged agitation was observed in some EMG+ DBA/2J (5 of 13), but not in A/J mice. The sleep time and MT counts were indifferent between the groups in DBA/2J mice. The EMG+ A/J group showed longer sleep time and less MT counts than the EMG- A/J group. Mean respiratory variables (baseline, hyperoxic/hypoxic responses) were not severely influenced by EMG+ in either strain. Individual values were more variable in EMG+ mice. Carotid body-mediated respiratory responses (decreased ventilation upon hyperoxia and increased ventilation upon mild hypoxia) during sleep were clearly observed in these neonatal mice with or without EMG instrumentation.
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Affiliation(s)
- Alexander Balbir
- Division of Physiology, Department of Environmental Health Sciences, The Johns Hopkins Bloomberg School of Public Health, E7610, 615 N. Wolfe Street, Baltimore, MD 21205, USA
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Porzionato A, Macchi V, Parenti A, De Caro R. Trophic factors in the carotid body. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 269:1-58. [PMID: 18779056 DOI: 10.1016/s1937-6448(08)01001-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The aim of the present study is to provide a review of the expression and action of trophic factors in the carotid body. In glomic type I cells, the following factors have been identified: brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, artemin, ciliary neurotrophic factor, insulin-like growth factors-I and -II, basic fibroblast growth factor, epidermal growth factor, transforming growth factor-alpha and -beta1, interleukin-1beta and -6, tumour necrosis factor-alpha, vascular endothelial growth factor, and endothelin-1 (ET-1). Growth factor receptors in the above cells include p75LNGFR, TrkA, TrkB, RET, GDNF family receptors alpha1-3, gp130, IL-6Ralpha, EGFR, FGFR1, IL1-RI, TNF-RI, VEGFR-1 and -2, ETA and ETB receptors, and PDGFR-alpha. Differential local expression of growth factors and corresponding receptors plays a role in pre- and postnatal development of the carotid body. Their local actions contribute toward producing the morphologic and molecular changes associated with chronic hypoxia and/or hypertension, such as cellular hyperplasia, extracellular matrix expansion, changes in channel densities, and neurotransmitter patterns. Neurotrophic factor production is also considered to play a key role in the therapeutic effects of intracerebral carotid body grafts in Parkinson's disease. Future research should also focus on trophic actions on carotid body type I cells by peptide neuromodulators, which are known to be present in the carotid body and to show trophic effects on other cell populations, that is, angiotensin II, adrenomedullin, bombesin, calcitonin, calcitonin gene-related peptide, cholecystokinin, erythropoietin, galanin, opioids, pituitary adenylate cyclase-activating polypeptide, atrial natriuretic peptide, somatostatin, tachykinins, neuropeptide Y, neurotensin, and vasoactive intestinal peptide.
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Affiliation(s)
- Andrea Porzionato
- Department of Human Anatomy and Physiology, University of Padova, Padova 35127, Italy
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Abstract
The ability to sense and react to changes in environmental oxygen levels is crucial to the survival of all aerobic life forms. In mammals, specialized tissues have evolved which can sense and rapidly respond to an acute reduction in oxygen and central to this ability in many is dynamic modulation of ion channels by hypoxia. The most widely studied oxygen-sensitive ion channels are potassium channels but oxygen sensing by members of both the calcium and sodium channel families has also been demonstrated. This chapter will focus on mechanisms of physiological oxygen sensing by ion channels, with particular emphasis on potassium channel function, and will highlight some of the consensuses and controversies within the field. Where data are available, this chapter will also make use of information gleaned from heterologous expression of recombinant proteins in an attempt to consolidate what we know currently about the molecular mechanisms of acute oxygen sensing by ion channels.
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Affiliation(s)
- Paul J Kemp
- Cardiff School of Bioscience, Cardiff University, Museum Avenue, Cardiff CF10 3US, UK.
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Shirahata M, Balbir A, Otsubo T, Fitzgerald RS. Role of acetylcholine in neurotransmission of the carotid body. Respir Physiol Neurobiol 2007; 157:93-105. [PMID: 17284361 DOI: 10.1016/j.resp.2006.12.010] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 12/11/2006] [Accepted: 12/27/2006] [Indexed: 01/19/2023]
Abstract
Acetylcholine (ACh) has been considered an important excitatory neurotransmitter in the carotid body (CB). Its physiological and pharmacological effects, metabolism, release, and receptors have been well documented in several species. Various nicotinic and muscarinic ACh receptors are present in both afferent nerve endings and glomus cells. Therefore, ACh can depolarize or hyperpolarize the cell membrane depending on the available receptor type in the vicinity. Binding of ACh to its receptor can create a wide variety of cellular responses including opening cation channels (nicotinic ACh receptor activation), releasing Ca(2+) from intracellular storage sites (via muscarinic ACh receptors), and modulating activities of K(+) and Ca(2+) channels. Interactions between ACh and other neurotransmitters (dopamine, adenosine, nitric oxide) have been known, and they may induce complicated responses. Cholinergic biology in the CB differs among species and even within the same species due to different genetic composition. Development and environment influence cholinergic biology. We discuss these issues in light of current knowledge of neuroscience.
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Affiliation(s)
- Machiko Shirahata
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
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