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Richter S, Pacak K, Kunst HPM, Januszewicz A, Nölting S, Remde H, Robledo M, Eisenhofer G, Timmers HJLM, Pamporaki C. Management and follow-up strategies for patients with head and neck paraganglioma. Eur J Endocrinol 2024; 191:389-398. [PMID: 39303070 PMCID: PMC11443905 DOI: 10.1093/ejendo/lvae113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 07/30/2024] [Accepted: 09/19/2024] [Indexed: 09/22/2024]
Abstract
OBJECTIVE Head-neck paragangliomas (HNPGLs) are rare tumors with approximately half arising due to germline pathogenic variants (PVs) in succinate dehydrogenase genes (SDHx). Patients with HNPGL have heterogeneous propensity to recur and metastasize. Thus, we aim to assess prevalence and predictors of recurrent (RD) and/or metastatic disease in patients with and without SDHx-related HNPGLs. DESIGN AND METHODS This cross-sectional study used retrospective data of 214 patients enrolled in six referral centers. Data included sex, age, primary tumor treatment, location, and size, biochemical phenotype, germline PVs, presence of RD (locoregional or new tumor), and/or metastasis. RESULTS Patients with and without SDHx-related HNPGLs showed 74% and 40% prevalence of RD, respectively. Patients without SDHx-related HNPGLs presented with recurrent tumors only in head-neck regions. The only independent predictor for RD in the entire cohort was presence of SDHx PVs. Metastatic prevalence reached 9%-13%. For patients with SDHx-related HNPGLs, large tumor size (>2.3 cm, OR:50.0, CI:2.6-977.6), young age at initial diagnosis (<42years, OR:27.3, CI:1.8-407.2), and presence of SDHB PV (OR:15.6; CI:1.5-164.8) were independent predictors of metastasis. For patients without SDHx-related HNPGLs, only carotid-body location was an independent predictor of metastasis (OR:18.9, CI:2.0-182.5). CONCLUSIONS Patients without SDHx-related HNPGLs require long-term follow-up due to high prevalence of RD with imaging largely restricted to head-neck regions. As carotid-body HNPGLs have the highest metastatic risk among sporadic tumors, radical treatment with frequent follow-up is suggested until population-based data are available. Importantly, patients with SDHx-related HNPGLs might benefit from early radical treatment when tumors are still small to reduce metastatic risk.
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Affiliation(s)
- Susan Richter
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Karel Pacak
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda 20892, MD, United States
| | - Henricus P M Kunst
- Department of Otorhinolaryngology, Radboud University Medical Centre, 6525 GA Nijmegen, The Netherlands
- Dutch Academic Alliance Skull Base Pathology, Maastricht University Medical Center+, 6229 HX Maastricht, The Netherlands
| | - Andrzej Januszewicz
- Department of Hypertension, National Institute of Cardiology, 04-628 Warsaw, Poland
| | - Svenja Nölting
- Medizinische Klinik and Poliklinik IV, Ludwig-Maximilians-Universität München, 80336 Munich, Germany
- Department for Endocrinology, Diabetology and Clinical Nutrition, Universitätsspital Zürich, 8091 Zurich, Switzerland
| | - Hanna Remde
- Division of Endocrinology and Diabetes, Department of Internal Medicine I, University Hospital, University of Würzburg, 97080 Würzburg, Germany
| | - Mercedes Robledo
- Hereditary Endocrine Cancer Group, CNIO, 28029 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 28029 Madrid, Spain
| | - Graeme Eisenhofer
- Department of Internal Medicine III, University Clinic Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
| | - Henri J L M Timmers
- Department of Internal Medicine, Radboud University Medical Centre, 6265 GA Nijmegen, The Netherlands
| | - Christina Pamporaki
- Department of Internal Medicine III, University Clinic Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany
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Prange-Barczynska M, Jones HA, Sugimoto Y, Cheng X, Lima JD, Ratnayaka I, Douglas G, Buckler KJ, Ratcliffe PJ, Keeley TP, Bishop T. Hif-2α programs oxygen chemosensitivity in chromaffin cells. J Clin Invest 2024; 134:e174661. [PMID: 39106106 PMCID: PMC11405041 DOI: 10.1172/jci174661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 07/29/2024] [Indexed: 08/09/2024] Open
Abstract
The study of transcription factors that determine specialized neuronal functions has provided invaluable insights into the physiology of the nervous system. Peripheral chemoreceptors are neurone-like electrophysiologically excitable cells that link the oxygen concentration of arterial blood to the neuronal control of breathing. In the adult, this oxygen chemosensitivity is exemplified by type I cells of the carotid body, and recent work has revealed one isoform of the hypoxia-inducible transcription factor (HIF), HIF-2α, as having a nonredundant role in the development and function of that organ. Here, we show that activation of HIF-2α, including isolated overexpression of HIF-2α but not HIF-1α, is sufficient to induce oxygen chemosensitivity in adult adrenal medulla. This phenotypic change in the adrenal medulla was associated with retention of extra-adrenal paraganglioma-like tissues resembling the fetal organ of Zuckerkandl, which also manifests oxygen chemosensitivity. Acquisition of chemosensitivity was associated with changes in the adrenal medullary expression of gene classes that are ordinarily characteristic of the carotid body, including G protein regulators and atypical subunits of mitochondrial cytochrome oxidase. Overall, the findings suggest that, at least in certain tissues, HIF-2α acts as a phenotypic driver for cells that display oxygen chemosensitivity, thus linking 2 major oxygen-sensing systems.
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Affiliation(s)
- Maria Prange-Barczynska
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Holly A Jones
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Yoichiro Sugimoto
- The Francis Crick Institute, London, United Kingdom
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany
| | - Xiaotong Cheng
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Joanna Dcc Lima
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Indrika Ratnayaka
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Gillian Douglas
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Keith J Buckler
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter J Ratcliffe
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
- The Francis Crick Institute, London, United Kingdom
| | - Thomas P Keeley
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
| | - Tammie Bishop
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
- Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, United Kingdom
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3
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Yuan X, Ruan W, Bobrow B, Carmeliet P, Eltzschig HK. Targeting hypoxia-inducible factors: therapeutic opportunities and challenges. Nat Rev Drug Discov 2024; 23:175-200. [PMID: 38123660 DOI: 10.1038/s41573-023-00848-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2023] [Indexed: 12/23/2023]
Abstract
Hypoxia-inducible factors (HIFs) are highly conserved transcription factors that are crucial for adaptation of metazoans to limited oxygen availability. Recently, HIF activation and inhibition have emerged as therapeutic targets in various human diseases. Pharmacologically desirable effects of HIF activation include erythropoiesis stimulation, cellular metabolism optimization during hypoxia and adaptive responses during ischaemia and inflammation. By contrast, HIF inhibition has been explored as a therapy for various cancers, retinal neovascularization and pulmonary hypertension. This Review discusses the biochemical mechanisms that control HIF stabilization and the molecular strategies that can be exploited pharmacologically to activate or inhibit HIFs. In addition, we examine medical conditions that benefit from targeting HIFs, the potential side effects of HIF activation or inhibition and future challenges in this field.
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Affiliation(s)
- Xiaoyi Yuan
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
| | - Wei Ruan
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Department of Anaesthesiology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Bentley Bobrow
- Department of Emergency Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Peter Carmeliet
- Laboratory of Angiogenesis & Vascular Metabolism, Center for Cancer Biology, VIB, Department of Oncology, KU Leuven, Leuven, Belgium
- Laboratory of Angiogenesis & Vascular Heterogeneity, Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Holger K Eltzschig
- Department of Anaesthesiology, Critical Care and Pain Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA.
- Outcomes Research Consortium, Cleveland, OH, USA.
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Karna B, Pellegata NS, Mohr H. Animal and Cell Culture Models of PPGLs - Achievements and Limitations. Horm Metab Res 2024; 56:51-64. [PMID: 38171372 DOI: 10.1055/a-2204-4549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Research on rare tumors heavily relies on suitable models for basic and translational research. Paragangliomas (PPGL) are rare neuroendocrine tumors (NET), developing from adrenal (pheochromocytoma, PCC) or extra-adrenal (PGL) chromaffin cells, with an annual incidence of 2-8 cases per million. While most PPGL cases exhibit slow growth and are primarily treated with surgery, limited systemic treatment options are available for unresectable or metastatic tumors. Scarcity of appropriate models has hindered PPGL research, preventing the translation of omics knowledge into drug and therapy development. Human PPGL cell lines are not available, and few animal models accurately replicate the disease's genetic and phenotypic characteristics. This review provides an overview of laboratory models for PPGLs, spanning cellular, tissue, organ, and organism levels. We discuss their features, advantages, and potential contributions to diagnostics and therapeutics. Interestingly, it appears that in the PPGL field, disease models already successfully implemented in other cancers have not been fully explored.
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Affiliation(s)
- Bhargavi Karna
- Institute for Diabetes and Cancer, Helmholtz Center Munich - German Research Center for Environmental Health, Neuherberg, Germany
| | - Natalia Simona Pellegata
- Institute for Diabetes and Cancer, Helmholtz Center Munich - German Research Center for Environmental Health, Neuherberg, Germany
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Hermine Mohr
- Institute for Diabetes and Cancer, Helmholtz Center Munich - German Research Center for Environmental Health, Neuherberg, Germany
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Rosenblum JS, Wang H, Nazari MA, Zhuang Z, Pacak K. Pacak-Zhuang syndrome: a model providing new insights into tumor syndromes. Endocr Relat Cancer 2023; 30:e230050. [PMID: 37450881 PMCID: PMC10512798 DOI: 10.1530/erc-23-0050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 07/14/2023] [Indexed: 07/18/2023]
Abstract
This article is a summary of the plenary lecture presented by Jared Rosenblum that was awarded the Manger Prize at the Sixth International Symposium on Pheochromocytoma/Paraganglioma held on 19-22 October 2022 in Prague, Czech Republic. Herein, we review our initial identification of a new syndrome of multiple paragangliomas, somatostatinomas, and polycythemia caused by early postzygotic mosaic mutations in EPAS1, encoding hypoxia-inducible factor 2 alpha (HIF-2α), and our continued exploration of new disease phenotypes in this syndrome, including vascular malformations and neural tube defects. Continued recruitment and close monitoring of patients with this syndrome as well as the generation and study of a corresponding disease mouse model as afforded by the pheochromocytoma/paraganglioma translational program at the National Institutes of Health has provided new insights into the natural history of these developmental anomalies and the pathophysiologic role of HIF-2α. Further, these studies have highlighted the importance of the timing of genetic defects in the development of related disease phenotypes. The recent discovery and continued study of this syndrome has not only rapidly evolved our understanding of pheochromocytoma and paraganglioma but also deepened our understanding of other developmental tumor syndromes, heritable syndromes, and sporadic diseases.
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Affiliation(s)
- Jared S Rosenblum
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Herui Wang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Matthew A Nazari
- Eunice Kennedy Shriver National Institute of Child Health and Development, Bethesda, MD, 20892
| | - Zhengping Zhuang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Karel Pacak
- Eunice Kennedy Shriver National Institute of Child Health and Development, Bethesda, MD, 20892
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6
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Jorgensen K, Song D, Weinstein J, Garcia OA, Pearson LN, Inclán M, Rivera-Chira M, León-Velarde F, Kiyamu M, Brutsaert TD, Bigham AW, Lee FS. High-Altitude Andean H194R HIF2A Allele Is a Hypomorphic Allele. Mol Biol Evol 2023; 40:msad162. [PMID: 37463421 PMCID: PMC10370452 DOI: 10.1093/molbev/msad162] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 06/15/2023] [Accepted: 07/03/2023] [Indexed: 07/20/2023] Open
Abstract
For over 10,000 years, Andeans have resided at high altitude where the partial pressure of oxygen challenges human survival. Recent studies have provided evidence for positive selection acting in Andeans on the HIF2A (also known as EPAS1) locus, which encodes for a central transcription factor of the hypoxia-inducible factor pathway. However, the precise mechanism by which this allele might lead to altitude-adaptive phenotypes, if any, is unknown. By analyzing whole genome sequencing data from 46 high-coverage Peruvian Andean genomes, we confirm evidence for positive selection acting on HIF2A and a unique pattern of variation surrounding the Andean-specific single nucleotide variant (SNV), rs570553380, which encodes for an H194R amino acid substitution in HIF-2α. Genotyping the Andean-associated SNV rs570553380 in a group of 299 Peruvian Andeans from Cerro de Pasco, Peru (4,338 m), reveals a positive association with increased fraction of exhaled nitric oxide, a marker of nitric oxide biosynthesis. In vitro assays show that the H194R mutation impairs binding of HIF-2α to its heterodimeric partner, aryl hydrocarbon receptor nuclear translocator. A knockin mouse model bearing the H194R mutation in the Hif2a gene displays decreased levels of hypoxia-induced pulmonary Endothelin-1 transcripts and protection against hypoxia-induced pulmonary hypertension. We conclude the Andean H194R HIF2A allele is a hypomorphic (partial loss of function) allele.
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Affiliation(s)
- Kelsey Jorgensen
- Department of Anthropology, University of California, Los Angeles, CA, USA
| | - Daisheng Song
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Julien Weinstein
- Department of Anthropology, The University of Michigan, Ann Arbor, MI, USA
| | - Obed A Garcia
- Department of Biomedical Data Science, Stanford University, Stanford, CA, USA
| | - Laurel N Pearson
- Department of Anthropology, The Pennsylvania State University, State College, PA, USA
| | - María Inclán
- División de. Estudios Políticos, Centro de Investigación y Docencia Económicas, Mexico City, CDMX, Mexico
| | - Maria Rivera-Chira
- Departamento de Ciencias Biológicas y Fisiológicas, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Lima, Peru
| | - Fabiola León-Velarde
- Departamento de Ciencias Biológicas y Fisiológicas, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Lima, Peru
| | - Melisa Kiyamu
- Departamento de Ciencias Biológicas y Fisiológicas, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Lima, Peru
| | - Tom D Brutsaert
- Department of Exercise Science, Syracuse University, Syracuse, NY, USA
| | - Abigail W Bigham
- Department of Anthropology, University of California, Los Angeles, CA, USA
| | - Frank S Lee
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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7
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Afsar B, Afsar RE. Hypoxia-inducible factors and essential hypertension: narrative review of experimental and clinical data. Pharmacol Rep 2023:10.1007/s43440-023-00497-x. [PMID: 37210694 DOI: 10.1007/s43440-023-00497-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/22/2023]
Abstract
Hypoxia-inducible factor (HIFs) is a new class of drug developed for the management of anemia in chronic kidney disease (CKD) patients. HIFs increase the production of erythropoietin in the kidney and liver, enhance the absorption and utilization of iron, and stimulate the maturation and proliferation of erythroid progenitor cells. Besides, HIFs regulate many physiologic processes by orchestrating the transcription of hundreds of genes. Essential hypertension (HT) is an epidemic worldwide. HIFs play a role in many biological processes involved in the regulation of blood pressure (BP). In the current review, we summarize pre-clinical and clinical studies investigating the relationship between HIFs and BP regulation in patients with CKD, conflicting issues, and discuss future potential strategies.
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Affiliation(s)
- Baris Afsar
- Department of Nephrology, School of Medicine, Suleyman Demirel University, Isparta, Turkey.
| | - Rengin Elsurer Afsar
- Department of Nephrology, School of Medicine, Suleyman Demirel University, Isparta, Turkey
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Hrabalova P, Bohuslavova R, Matejkova K, Papousek F, Sedmera D, Abaffy P, Kolar F, Pavlinkova G. Dysregulation of hypoxia-inducible factor 1α in the sympathetic nervous system accelerates diabetic cardiomyopathy. Cardiovasc Diabetol 2023; 22:88. [PMID: 37072781 PMCID: PMC10114478 DOI: 10.1186/s12933-023-01824-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 04/03/2023] [Indexed: 04/20/2023] Open
Abstract
BACKGROUND An altered sympathetic nervous system is implicated in many cardiac pathologies, ranging from sudden infant death syndrome to common diseases of adulthood such as hypertension, myocardial ischemia, cardiac arrhythmias, myocardial infarction, and heart failure. Although the mechanisms responsible for disruption of this well-organized system are the subject of intensive investigations, the exact processes controlling the cardiac sympathetic nervous system are still not fully understood. A conditional knockout of the Hif1a gene was reported to affect the development of sympathetic ganglia and sympathetic innervation of the heart. This study characterized how the combination of HIF-1α deficiency and streptozotocin (STZ)-induced diabetes affects the cardiac sympathetic nervous system and heart function of adult animals. METHODS Molecular characteristics of Hif1a deficient sympathetic neurons were identified by RNA sequencing. Diabetes was induced in Hif1a knockout and control mice by low doses of STZ treatment. Heart function was assessed by echocardiography. Mechanisms involved in adverse structural remodeling of the myocardium, i.e. advanced glycation end products, fibrosis, cell death, and inflammation, was assessed by immunohistological analyses. RESULTS We demonstrated that the deletion of Hif1a alters the transcriptome of sympathetic neurons, and that diabetic mice with the Hif1a-deficient sympathetic system have significant systolic dysfunction, worsened cardiac sympathetic innervation, and structural remodeling of the myocardium. CONCLUSIONS We provide evidence that the combination of diabetes and the Hif1a deficient sympathetic nervous system results in compromised cardiac performance and accelerated adverse myocardial remodeling, associated with the progression of diabetic cardiomyopathy.
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Affiliation(s)
- Petra Hrabalova
- Laboratory of Molecular Pathogenetics, Institute of Biotechnology CAS, BIOCEV, Vestec, Czechia
- Charles University, Prague, Czechia
| | - Romana Bohuslavova
- Laboratory of Molecular Pathogenetics, Institute of Biotechnology CAS, BIOCEV, Vestec, Czechia
| | - Katerina Matejkova
- Laboratory of Molecular Pathogenetics, Institute of Biotechnology CAS, BIOCEV, Vestec, Czechia
| | | | - David Sedmera
- Institute of Physiology CAS, Prague, Czechia
- Institute of Anatomy, Charles University, Prague, Czechia
| | - Pavel Abaffy
- Laboratory of Gene Expression, Institute of Biotechnology CAS, BIOCEV, Vestec, Czechia
| | | | - Gabriela Pavlinkova
- Laboratory of Molecular Pathogenetics, Institute of Biotechnology CAS, BIOCEV, Vestec, Czechia.
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9
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Lazarov NE, Atanasova DY. Stem Cell Niche in the Mammalian Carotid Body. ADVANCES IN ANATOMY, EMBRYOLOGY, AND CELL BIOLOGY 2023; 237:139-153. [PMID: 37946081 DOI: 10.1007/978-3-031-44757-0_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Accumulating evidence suggests that the mammalian carotid body (CB) constitutes a neurogenic center that contains a functionally active germinal niche. A variety of transcription factors is required for the generation of a precursor cell pool in the developing CB. Most of them are later silenced in their progeny, thus allowing for the maturation of the differentiated neurons. In the adult CB, neurotransmitters and vascular cytokines released by glomus cells upon exposure to chronic hypoxia act as paracrine signals that induce proliferation and differentiation of pluripotent stem cells, neuronal and vascular progenitors. Key proliferation markers such as Ki-67 and BrdU are widely used to evaluate the proliferative status of the CB parenchymal cells in the initial phase of this neurogenesis. During hypoxia sustentacular cells which are dormant cells in normoxic conditions can proliferate and differentiate into new glomus cells. However, more recent data have revealed that the majority of the newly formed glomus cells is derived from the glomus cell lineage itself. The mature glomus cells express numerous trophic and growth factors, and their corresponding receptors, which act on CB cell populations in autocrine or paracrine ways. Some of them initially serve as target-derived survival factors and then as signaling molecules in developing vascular targets. Morphofunctional insights into the cellular interactions in the CB stem cell microenvironment can be helpful in further understanding the therapeutic potential of the CB cell niche.
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Affiliation(s)
- Nikolai E Lazarov
- Department of Anatomy and Histology, Faculty of Medicine, Medical University of Sofia, Sofia, Bulgaria.
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10
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Colinas O, Moreno-Domínguez A, Ortega-Sáenz P, López-Barneo J. Constitutive Expression of Hif2α Confers Acute O 2 Sensitivity to Carotid Body Glomus Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1427:153-162. [PMID: 37322346 DOI: 10.1007/978-3-031-32371-3_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Acute oxygen (O2) sensing and adaptation to hypoxia are essential for physiological homeostasis. The prototypical acute O2 sensing organ is the carotid body, which contains chemosensory glomus cells expressing O2-sensitive K+ channels. Inhibition of these channels during hypoxia leads to cell depolarization, transmitter release, and activation of afferent sensory fibers terminating in the brain stem respiratory and autonomic centers. Focusing on recent data, here we discuss the special sensitivity of glomus cell mitochondria to changes in O2 tension due to Hif2α-dependent expression of several atypical mitochondrial electron transport chain subunits and enzymes. These are responsible for an accelerated oxidative metabolism and the strict dependence of mitochondrial complex IV activity on O2 availability. We report that ablation of Epas1 (the gene coding Hif2α) causes a selective downregulation of the atypical mitochondrial genes and a strong inhibition of glomus cell acute responsiveness to hypoxia. Our observations indicate that Hif2α expression is required for the characteristic metabolic profile of glomus cells and provide a mechanistic explanation for the acute O2 regulation of breathing.
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Affiliation(s)
- Olalla Colinas
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Alejandro Moreno-Domínguez
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, 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, Seville, Spain
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, 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, Seville, Spain.
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
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11
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Townley IK, Babin CH, Murphy TE, Summa CM, Rees BB. Genomic analysis of hypoxia inducible factor alpha in ray-finned fishes reveals missing Ohnologs and evidence of widespread positive selection. Sci Rep 2022; 12:22312. [PMID: 36566251 PMCID: PMC9789988 DOI: 10.1038/s41598-022-26876-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/20/2022] [Indexed: 12/25/2022] Open
Abstract
As aquatic hypoxia worsens on a global scale, fishes will become increasingly challenged by low oxygen, and understanding the molecular basis of their response to hypoxia may help to better define the capacity of fishes to cope with this challenge. The hypoxia inducible factor (HIF) plays a critical role in the molecular response to hypoxia by activating the transcription of genes that serve to improve oxygen delivery to the tissues or enhance the capacity of tissues to function at low oxygen. The current study examines the molecular evolution of genes encoding the oxygen-dependent HIFα subunit (HIFA) in the ray-finned fishes (Actinopterygii). Genomic analyses demonstrate that several lineages retain four paralogs of HIFA predicted from two rounds of genome duplication at the base of vertebrate evolution, broaden the known distribution of teleost-specific HIFA paralogs, and provide evidence for salmonid-specific HIFA duplicates. Evolution of the HIFA gene family is characterized by widespread episodic positive selection at amino acid sites that potentially mediate protein stability, protein-protein interactions, and transcriptional regulation. HIFA transcript abundance depends upon paralog, tissue, and fish lineage. A phylogenetically-informed gene nomenclature is proposed along with avenues for future research on this critical family of transcription factors.
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Affiliation(s)
- Ian K. Townley
- Science Department, Saint George’s School, Spokane, WA 99208 USA
| | - Courtney H. Babin
- grid.266835.c0000 0001 2179 5031Department of Biological Sciences, University of New Orleans, New Orleans, LA 70148 USA
| | - Taylor E. Murphy
- grid.266835.c0000 0001 2179 5031Department of Biological Sciences, University of New Orleans, New Orleans, LA 70148 USA
| | - Christopher M. Summa
- grid.266835.c0000 0001 2179 5031Department of Computer Sciences, University of New Orleans, New Orleans, LA 70148 USA
| | - Bernard B. Rees
- grid.266835.c0000 0001 2179 5031Department of Biological Sciences, University of New Orleans, New Orleans, LA 70148 USA
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12
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Oxygen regulation of breathing is abolished in mitochondrial complex III-deficient arterial chemoreceptors. Proc Natl Acad Sci U S A 2022; 119:e2202178119. [PMID: 36122208 PMCID: PMC9522341 DOI: 10.1073/pnas.2202178119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Oxygen sensing by chemoreceptor glomus cells in the carotid body plays an essential adaptive function in health and disease; however, the underlying mechanisms are not fully understood. Glomus cells survive genetic disruption of mitochondrial complex III, although this results in a functional disconnection between the distal and proximal components of the mitochondrial electron transport chain (ETC). These cells exhibit selective abolition of mitochondrial and cellular responsiveness to hypoxia, as well as altered systemic hyperventilation and acclimatization to hypoxia, indicating that acute oxygen-sensing and -signaling during hypoxia result from the integrated action of mitochondrial ETC components. The mitochondrial ETC emerges as a complex oxygen-sensing and -signaling system of potential pathophysiological relevance in maladaptive responses to hypoxia. Acute oxygen (O2) sensing is essential for adaptation of organisms to hypoxic environments or medical conditions with restricted exchange of gases in the lung. The main acute O2-sensing organ is the carotid body (CB), which contains neurosecretory chemoreceptor (glomus) cells innervated by sensory fibers whose activation by hypoxia elicits hyperventilation and increased cardiac output. Glomus cells have mitochondria with specialized metabolic and electron transport chain (ETC) properties. Reduced mitochondrial complex (MC) IV activity by hypoxia leads to production of signaling molecules (NADH and reactive O2 species) in MCI and MCIII that modulate membrane ion channel activity. We studied mice with conditional genetic ablation of MCIII that disrupts the ETC in the CB and other catecholaminergic tissues. Glomus cells survived MCIII dysfunction but showed selective abolition of responsiveness to hypoxia (increased [Ca2+] and transmitter release) with normal responses to other stimuli. Mitochondrial hypoxic NADH and reactive O2 species signals were also suppressed. MCIII-deficient mice exhibited strong inhibition of the hypoxic ventilatory response and altered acclimatization to sustained hypoxia. These data indicate that a functional ETC, with coupling between MCI and MCIV, is required for acute O2 sensing. O2 regulation of breathing results from the integrated action of mitochondrial ETC complexes in arterial chemoreceptors.
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13
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Reiterer M, Eakin A, Johnson RS, Branco CM. Hyperoxia Reprogrammes Microvascular Endothelial Cell Response to Hypoxia in an Organ-Specific Manner. Cells 2022; 11:cells11162469. [PMID: 36010546 PMCID: PMC9406746 DOI: 10.3390/cells11162469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/27/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
Organ function relies on microvascular networks to maintain homeostatic equilibrium, which varies widely in different organs and during different physiological challenges. The endothelium role in this critical process can only be evaluated in physiologically relevant contexts. Comparing the responses to oxygen flux in primary murine microvascular EC (MVEC) obtained from brain and lung tissue reveals that supra-physiological oxygen tensions can compromise MVEC viability. Brain MVEC lose mitochondrial activity and undergo significant alterations in electron transport chain (ETC) composition when cultured under standard, non-physiological atmospheric oxygen levels. While glycolytic capacity of both lung and brain MVEC are unchanged by environmental oxygen, the ability to trigger a metabolic shift when oxygen levels drop is greatly compromised following exposure to hyperoxia. This is particularly striking in MVEC from the brain. This work demonstrates that the unique metabolism and function of organ-specific MVEC (1) can be reprogrammed by external oxygen, (2) that this reprogramming can compromise MVEC survival and, importantly, (3) that ex vivo modelling of endothelial function is significantly affected by culture conditions. It further demonstrates that physiological, metabolic and functional studies performed in non-physiological environments do not represent cell function in situ, and this has serious implications in the interpretation of cell-based pre-clinical models.
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Affiliation(s)
- Moritz Reiterer
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Amanda Eakin
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
| | - Randall S. Johnson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Cristina M. Branco
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
- Correspondence:
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14
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Ivy CM, Velotta JP, Cheviron ZA, Scott GR. Genetic variation in HIF-2α attenuates ventilatory sensitivity and carotid body growth in chronic hypoxia in high-altitude deer mice. J Physiol 2022; 600:4207-4225. [PMID: 35797482 DOI: 10.1113/jp282798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 06/27/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS High-altitude natives of many species have experienced natural selection on the gene encoding HIF-2α, Epas1, including high-altitude populations of deer mice. HIF-2α regulates ventilation and carotid body growth in hypoxia, so the genetic variants in Epas1 in high-altitude natives may underlie evolved changes in control of breathing. Deer mice from controlled crosses between high- and low-altitude populations were used to examine the effects of Epas1 genotype on an admixed genomic background. The high-altitude variant was associated with reduced ventilatory chemosensitivity and carotid body growth in chronic hypoxia, but had no effects on haematology. The results help us better understand the genetic basis for the unique physiological phenotype of high-altitude natives. ABSTRACT The gene encoding HIF-2α, Epas1, has experienced a history of natural selection in many high-altitude taxa, but the functional role of mutations in this gene are still poorly understood. We investigated the influence of the high-altitude variant of Epas1 in North American deer mice (Peromyscus maniculatus) on control of breathing and carotid body growth during chronic hypoxia. We created hybrids between high- and low-altitude populations of deer mice to disrupt linkages between genetic loci so physiological effects of Epas1 alleles (Epas1H and Epas1L , respectively) could be examined on an admixed genomic background. In general, chronic hypoxia (4 weeks at 12 kPa O2 ) enhanced ventilatory chemosensitivity (assessed as the acute ventilatory response to hypoxia), increased total ventilation and arterial O2 saturation during progressive poikilocapnic hypoxia, and increased haematocrit and blood haemoglobin content across genotypes. However, effects of chronic hypoxia on ventilatory chemosensitivity were attenuated in mice that were homozygous for the high-altitude Epas1 allele (Epas1H/H ). Carotid body growth and glomus cell hyperplasia, which was strongly induced in Epas1L/L mice in chronic hypoxia, was not observed in Epas1H/H mice. Epas1 genotype also modulated the effects of chronic hypoxia on metabolism and body temperature depression in hypoxia, but had no effects on haematological traits. These findings confirm the important role of HIF-2α in modulating ventilatory sensitivity and carotid body growth in chronic hypoxia, and show that genetic variation in Epas1 is responsible for evolved changes in the control of breathing and metabolism in high-altitude deer mice. Abstract figure legend ventilation and carotid body growth in hypoxia, so we investigated the role genetic variants in Epas1 in highaltitude deer mice on the control of breathing. In the lab, hybrids between high- and lowaltitude populations of deer mice were created to disrupt linkages between genetic loci so physiological effects of Epas1 alleles (Epas1H and Epas1L, respectively) could be examined on an admixed genomic background. The high-altitude variant was associated with reduced ventilatory chemosensitivity and carotid body growth after 4 weeks of chronic hypoxia, compared to mice homozygous for the low-altitude allele (Epas1LL). These results help us better understand the genetic basis for the unique physiological phenotype of high-altitude natives. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Catherine M Ivy
- Department of Biology, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Jonathan P Velotta
- Department of Biological Sciences, University of Denver, Denver, CO, 80210, USA
| | - Zachary A Cheviron
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | - Graham R Scott
- Department of Biology, McMaster University, Hamilton, ON, L8S 4K1, Canada
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15
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Differential HIF2α Protein Expression in Human Carotid Body and Adrenal Medulla under Physiologic and Tumorigenic Conditions. Cancers (Basel) 2022; 14:cancers14122986. [PMID: 35740651 PMCID: PMC9221385 DOI: 10.3390/cancers14122986] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/10/2022] [Accepted: 06/15/2022] [Indexed: 11/17/2022] Open
Abstract
Hypoxia-inducible factors (HIF) 2α and 1α are the major oxygen-sensing molecules in eukaryotic cells. HIF2α has been pathogenically linked to paraganglioma and pheochromocytoma (PPGL) arising in sympathetic paraganglia or the adrenal medulla (AM), respectively. However, its involvement in the pathogenesis of paraganglioma arising in the carotid body (CB) or other parasympathetic ganglia in the head and neck (HNPGL) remains to be defined. Here, we retrospectively analyzed HIF2α by immunohistochemistry in 62 PPGL/HNPGL and human CB and AM, and comprehensively evaluated the HIF-related transcriptome of 202 published PPGL/HNPGL. We report that HIF2α is barely detected in the AM, but accumulates at high levels in PPGL, mostly (but not exclusively) in those with loss-of-function mutations in VHL and genes encoding components of the succinate dehydrogenase (SDH) complex. This is associated with upregulation of EPAS1 and the HIF2α-regulated genes COX4I2 and ADORA2A. In contrast, HIF2α and HIF2α-regulated genes are highly expressed in CB and HNPGL, irrespective of VHL and SDH dysfunctions. We also found that HIF2α and HIF1α protein expressions are not correlated in PPGL nor HNPGL. In addition, HIF1α-target genes are almost exclusively overexpressed in VHL-mutated HNPGL/PPGL. Collectively, the data suggest that involvement of HIF2α in the physiology and tumor pathology of human paraganglia is organ-of-origin-dependent and HIF1α-independent.
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16
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Han J, Wan Q, Seo GY, Kim K, el Baghdady S, Lee JH, Kronenberg M, Liu YC. Hypoxia induces adrenomedullin from lung epithelia, stimulating ILC2 inflammation and immunity. J Exp Med 2022; 219:e20211985. [PMID: 35532553 PMCID: PMC9093746 DOI: 10.1084/jem.20211985] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 02/21/2022] [Accepted: 04/04/2022] [Indexed: 07/25/2023] Open
Abstract
Hypoxia contributes to airway inflammation and remodeling in several lung diseases; however, exactly how hypoxic pulmonary epithelium regulates allergic inflammation remains to be fully characterized. Here, we report that conditional deletion of the E3 ubiquitin ligase VHL in lung epithelial cells resulted in exacerbated type 2 responses accompanied by selective increase of group 2 innate lymphoid cells (ILC2s) at steady state and following inflammation or helminth infection. Ablation of expression of the hypoxia-inducible factor 2α (HIF2α) significantly reversed VHL-mediated ILC2 activation. VHL deficiency in lung epithelial cells caused increased expression of the peptide hormone adrenomedullin (ADM), and our data suggest that HIF2α controls Adm expression. ADM directly promoted ILC2 activation both in vitro and in vivo. Our findings indicate that the hypoxic response mediated by the VHL-HIF2α axis is critical for control of pulmonary type 2 responses by increasing ADM expression in lung epithelia, causing ILC2 activation.
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Affiliation(s)
- Jihye Han
- La Jolla Institute for Immunology, La Jolla, CA
| | - Qingqing Wan
- La Jolla Institute for Immunology, La Jolla, CA
- Institute for Immunology, Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing, China
| | | | - Kenneth Kim
- La Jolla Institute for Immunology, La Jolla, CA
| | | | - Jee H. Lee
- La Jolla Institute for Immunology, La Jolla, CA
| | - Mitchell Kronenberg
- La Jolla Institute for Immunology, La Jolla, CA
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Yun-Cai Liu
- La Jolla Institute for Immunology, La Jolla, CA
- Institute for Immunology, Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing, China
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17
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Abstract
Oxygen (O2) is essential for life and therefore the supply of sufficient O2 to the tissues is a major physiological challenge. In mammals, a deficit of O2 (hypoxia) triggers rapid cardiorespiratory reflexes (e.g. hyperventilation and increased heart output) that within a few seconds increase the uptake of O2 by the lungs and its distribution throughout the body. The prototypical acute O2-sensing organ is the carotid body (CB), which contains sensory glomus cells expressing O2-regulated ion channels. In response to hypoxia, glomus cells depolarize and release transmitters which activate afferent fibers terminating at the brainstem respiratory and autonomic centers. In this review, we summarize the basic properties of CB chemoreceptor cells and the essential role played by their specialized mitochondria in acute O2 sensing and signaling. We focus on recent data supporting a "mitochondria-to-membrane signaling" model of CB chemosensory transduction. The possibility that the differential expression of specific subunit isoforms and enzymes could allow mitochondria to play a generalized adaptive O2-sensing and signaling role in a wide variety of cells is also discussed.
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Affiliation(s)
- José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, 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, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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18
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Eckardt L, Prange-Barczynska M, Hodson EJ, Fielding JW, Cheng X, Lima JDCC, Kurlekar S, Douglas G, Ratcliffe PJ, Bishop T. Developmental role of PHD2 in the pathogenesis of pseudohypoxic pheochromocytoma. Endocr Relat Cancer 2021; 28:757-772. [PMID: 34658364 PMCID: PMC8558849 DOI: 10.1530/erc-21-0211] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 09/20/2021] [Indexed: 01/03/2023]
Abstract
Despite a general role for the HIF hydroxylase system in cellular oxygen sensing and tumour hypoxia, cancer-associated mutations of genes in this pathway, including PHD2, PHD1, EPAS1 (encoding HIF-2α) are highly tissue-restricted, being observed in pseudohypoxic pheochromocytoma and paraganglioma (PPGL) but rarely, if ever, in other tumours. In an effort to understand that paradox and gain insights into the pathogenesis of pseudohypoxic PPGL, we constructed mice in which the principal HIF prolyl hydroxylase, Phd2, is inactivated in the adrenal medulla using TH-restricted Cre recombinase. Investigation of these animals revealed a gene expression pattern closely mimicking that of pseudohypoxic PPGL. Spatially resolved analyses demonstrated a binary distribution of two contrasting patterns of gene expression among adrenal medullary cells. Phd2 inactivation resulted in a marked shift in this distribution towards a Pnmt-/Hif-2α+/Rgs5+ population. This was associated with morphological abnormalities of adrenal development, including ectopic TH+ cells within the adrenal cortex and external to the adrenal gland. These changes were ablated by combined inactivation of Phd2 with Hif-2α, but not Hif-1α. However, they could not be reproduced by inactivation of Phd2 in adult life, suggesting that they arise from dysregulation of this pathway during adrenal development. Together with the clinical observation that pseudohypoxic PPGL manifests remarkably high heritability, our findings suggest that this type of tumour likely arises from dysregulation of a tissue-restricted action of the PHD2/HIF-2α pathway affecting adrenal development in early life and provides a model for the study of the relevant processes.
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Affiliation(s)
- Luise Eckardt
- Target Discovery Institute, University of Oxford, Oxford, UK
- Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Maria Prange-Barczynska
- Target Discovery Institute, University of Oxford, Oxford, UK
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
| | - Emma J Hodson
- The Francis Crick Institute, London, UK
- The Department of Experimental Medicine and Immunotherapeutics, University of Cambridge, Cambridge, UK
| | - James W Fielding
- Target Discovery Institute, University of Oxford, Oxford, UK
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
| | - Xiaotong Cheng
- Target Discovery Institute, University of Oxford, Oxford, UK
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
| | | | - Samvid Kurlekar
- Target Discovery Institute, University of Oxford, Oxford, UK
| | - Gillian Douglas
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Peter J Ratcliffe
- Target Discovery Institute, University of Oxford, Oxford, UK
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, UK
- The Francis Crick Institute, London, UK
- Correspondence should be addressed to P J Ratcliffe or T Bishop: or
| | - Tammie Bishop
- Target Discovery Institute, University of Oxford, Oxford, UK
- Correspondence should be addressed to P J Ratcliffe or T Bishop: or
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19
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Watts D, Bechmann N, Meneses A, Poutakidou IK, Kaden D, Conrad C, Krüger A, Stein J, El-Armouche A, Chavakis T, Eisenhofer G, Peitzsch M, Wielockx B. HIF2α regulates the synthesis and release of epinephrine in the adrenal medulla. J Mol Med (Berl) 2021; 99:1655-1666. [PMID: 34480587 PMCID: PMC8542008 DOI: 10.1007/s00109-021-02121-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 02/06/2023]
Abstract
The adrenal gland and its hormones regulate numerous fundamental biological processes; however, the impact of hypoxia signaling on adrenal function remains poorly understood. Here, we reveal that deficiency of HIF (hypoxia inducible factors) prolyl hydroxylase domain protein-2 (PHD2) in the adrenal medulla of mice results in HIF2α-mediated reduction in phenylethanolamine N-methyltransferase (PNMT) expression, and consequent reduction in epinephrine synthesis. Simultaneous loss of PHD2 in renal erythropoietin (EPO)-producing cells (REPCs) stimulated HIF2α-driven EPO overproduction, excessive RBC formation (erythrocytosis), and systemic hypoglycemia, which is necessary and sufficient to enhance exocytosis of epinephrine from the adrenal medulla. Based on these results, we propose that the PHD2-HIF2α axis in the adrenal medulla regulates the synthesis of epinephrine, whereas in REPCs, it indirectly induces the release of this hormone. Our findings are also highly relevant to the testing of small molecule PHD inhibitors in phase III clinical trials for patients with renal anemia. KEY MESSAGES: HIF2α and not HIF1α modulates PNMT during epinephrine synthesis in chromaffin cells. The PHD2-HIF2α-EPO axis induces erythrocytosis and hypoglycemia. Reduced systemic glucose facilitates exocytosis of epinephrine from adrenal gland.
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Affiliation(s)
- Deepika Watts
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Nicole Bechmann
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.,Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rehbruecke, 14558, Nuthetal, Germany.,German Center for Diabetes Research (DZD), 85764, München-Neuherberg, Germany
| | - Ana Meneses
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ioanna K Poutakidou
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Denise Kaden
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Catleen Conrad
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Anja Krüger
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Johanna Stein
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ali El-Armouche
- Department of Pharmacology and Toxicology, Medical Faculty, Technische Universität Dresden, 01307, Dresden, Germany
| | - Triantafyllos Chavakis
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Graeme Eisenhofer
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.,Department of Medicine III, Medical Faculty, Technische Universität Dresden, 01307, Dresden, Germany
| | - Mirko Peitzsch
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Ben Wielockx
- Institute of Clinical Chemistry and Laboratory Medicine, Technische Universität Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
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20
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Lactate sensing mechanisms in arterial chemoreceptor cells. Nat Commun 2021; 12:4166. [PMID: 34230483 PMCID: PMC8260783 DOI: 10.1038/s41467-021-24444-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 06/08/2021] [Indexed: 12/17/2022] Open
Abstract
Classically considered a by-product of anaerobic metabolism, lactate is now viewed as a fundamental fuel for oxidative phosphorylation in mitochondria, and preferred over glucose by many tissues. Lactate is also a signaling molecule of increasing medical relevance. Lactate levels in the blood can increase in both normal and pathophysiological conditions (e.g., hypoxia, physical exercise, or sepsis), however the manner by which these changes are sensed and induce adaptive responses is unknown. Here we show that the carotid body (CB) is essential for lactate homeostasis and that CB glomus cells, the main oxygen sensing arterial chemoreceptors, are also lactate sensors. Lactate is transported into glomus cells, leading to a rapid increase in the cytosolic NADH/NAD+ ratio. This in turn activates membrane cation channels, leading to cell depolarization, action potential firing, and Ca2+ influx. Lactate also decreases intracellular pH and increases mitochondrial reactive oxygen species production, which further activates glomus cells. Lactate and hypoxia, although sensed by separate mechanisms, share the same final signaling pathway and jointly activate glomus cells to potentiate compensatory cardiorespiratory reflexes. Lactate levels in blood change during hypoxia or exercise, however whether this variable is sensed to evoke adaptive responses is unknown. Here the authors show that oxygen-sensing carotid body cells stimulated by hypoxia are also activated by lactate to potentiate a compensatory ventilatory response.
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21
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Lambden S, Cowburn AS, Macias D, Garrud TAC, Krause BJ, Giussani DA, Summers C, Johnson RS. Endothelial cell regulation of systemic haemodynamics and metabolism acts through the HIF transcription factors. Intensive Care Med Exp 2021; 9:28. [PMID: 34114090 PMCID: PMC8192653 DOI: 10.1186/s40635-021-00390-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 04/27/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The vascular endothelium has important endocrine and paracrine roles, particularly in the regulation of vascular tone and immune function, and it has been implicated in the pathophysiology of a range of cardiovascular and inflammatory conditions. This study uses a series of transgenic murine models to explore for the first time the role of the hypoxia-inducible factors, HIF-1α and HIF-2α in the pulmonary and systemic circulations as potential regulators of systemic vascular function in normoxic or hypoxic conditions and in response to inflammatory stress. We developed a series of transgenic mouse models, the HIF-1α Tie2Cre, deficient in HIF1-α in the systemic and pulmonary vascular endothelium and the L1Cre, a pulmonary endothelium specific knockout of HIF-1α or HIF-2α. In vivo, arterial blood pressure and metabolic activity were monitored continuously in normal atmospheric conditions and following an acute stimulus with hypoxia (10%) or lipopolysaccharide (LPS). Ex vivo, femoral artery reactivity was assessed using wire myography. RESULTS Under normoxia, the HIF-1α Tie2Cre mouse had increased systolic and diastolic arterial pressure compared to litter mate controls over the day-night cycle under normal environmental conditions. VO2 and VCO2 were also increased. Femoral arteries displayed impaired endothelial relaxation in response to acetylcholine mediated by a reduction in the nitric oxide dependent portion of the response. HIF-1α L1Cre mice displayed a similar pattern of increased systemic blood pressure, metabolic rate and impaired vascular relaxation without features of pulmonary hypertension, polycythaemia or renal dysfunction under normal conditions. In response to acute hypoxia, deficiency of HIF-1α was associated with faster resolution of hypoxia-induced haemodynamic and metabolic compromise. In addition, systemic haemodynamics were less compromised by LPS treatment. CONCLUSIONS These data show that deficiency of HIF-1α in the systemic or pulmonary endothelium is associated with increased systemic blood pressure and metabolic rate, a pattern that persists in both normoxic conditions and in response to acute stress with potential implications for our understanding of the pathophysiology of vascular dysfunction in acute and chronic disease.
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Affiliation(s)
- Simon Lambden
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Andrew S Cowburn
- National Heart and Lung Institute, Imperial College London, London, UK
| | - David Macias
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Tessa A C Garrud
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | - Bernardo J Krause
- Department of Neonatology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Dino A Giussani
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK
| | | | - Randall S Johnson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3EG, UK. .,Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden.
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22
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Macias D, Moore S, Crosby A, Southwood M, Du X, Tan H, Xie S, Vassallo A, Wood AJT, Wallace EM, Cowburn AS. Targeting HIF2α-ARNT hetero-dimerisation as a novel therapeutic strategy for pulmonary arterial hypertension. Eur Respir J 2021; 57:13993003.02061-2019. [PMID: 32972983 PMCID: PMC7930471 DOI: 10.1183/13993003.02061-2019] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 08/26/2020] [Indexed: 12/13/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a destructive disease of the pulmonary vasculature often leading to right heart failure and death. Current therapeutic intervention strategies only slow disease progression. The role of aberrant hypoxia-inducible factor (HIF)2α stability and function in the initiation and development of pulmonary hypertension (PH) has been an area of intense interest for nearly two decades.Here we determine the effect of a novel HIF2α inhibitor (PT2567) on PH disease initiation and progression, using two pre-clinical models of PH. Haemodynamic measurements were performed, followed by collection of heart, lung and blood for pathological, gene expression and biochemical analysis. Blood outgrowth endothelial cells from idiopathic PAH patients were used to determine the impact of HIF2α-inhibition on endothelial function.Global inhibition of HIF2a reduced pulmonary vascular haemodynamics and pulmonary vascular remodelling in both su5416/hypoxia prevention and intervention models. PT2567 intervention reduced the expression of PH-associated target genes in both lung and cardiac tissues and restored plasma nitrite concentration. Treatment of monocrotaline-exposed rodents with PT2567 reduced the impact on cardiovascular haemodynamics and promoted a survival advantage. In vitro, loss of HIF2α signalling in human pulmonary arterial endothelial cells suppresses target genes associated with inflammation, and PT2567 reduced the hyperproliferative phenotype and overactive arginase activity in blood outgrowth endothelial cells from idiopathic PAH patients. These data suggest that targeting HIF2α hetero-dimerisation with an orally bioavailable compound could offer a new therapeutic approach for PAH. Future studies are required to determine the role of HIF in the heterogeneous PAH population.
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Affiliation(s)
- David Macias
- CRUK Cambridge Centre Early Detection Programme, Dept of Oncology, Hutchison/MRC Research Centre, University of Cambridge, Cambridge, UK.,Both authors contributed equally
| | - Stephen Moore
- Dept of Medicine, University of Cambridge, Cambridge, UK.,Both authors contributed equally
| | - Alexi Crosby
- Dept of Medicine, University of Cambridge, Cambridge, UK
| | - Mark Southwood
- Dept of Pathology, Papworth Hospital National Health Service Foundation Trust, Cambridge, UK
| | - Xinlin Du
- Peloton Therapeutics Inc. (a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA), Dallas, TX, USA
| | - Huiling Tan
- Peloton Therapeutics Inc. (a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA), Dallas, TX, USA
| | - Shanhai Xie
- Peloton Therapeutics Inc. (a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA), Dallas, TX, USA
| | | | | | - Eli M Wallace
- Peloton Therapeutics Inc. (a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA), Dallas, TX, USA
| | - Andrew S Cowburn
- Dept of Medicine, University of Cambridge, Cambridge, UK .,National Heart and Lung Institute, Imperial College London, London, UK
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23
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Pullamsetti SS, Mamazhakypov A, Weissmann N, Seeger W, Savai R. Hypoxia-inducible factor signaling in pulmonary hypertension. J Clin Invest 2021; 130:5638-5651. [PMID: 32881714 DOI: 10.1172/jci137558] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pulmonary hypertension (PH) is characterized by pulmonary artery remodeling that can subsequently culminate in right heart failure and premature death. Emerging evidence suggests that hypoxia-inducible factor (HIF) signaling plays a fundamental and pivotal role in the pathogenesis of PH. This Review summarizes the regulation of HIF isoforms and their impact in various PH subtypes, as well as the elaborate conditional and cell-specific knockout mouse studies that brought the role of this pathway to light. We also discuss the current preclinical status of pan- and isoform-selective HIF inhibitors, and propose new research areas that may facilitate HIF isoform-specific inhibition as a novel therapeutic strategy for PH and right heart failure.
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Affiliation(s)
- Soni Savai Pullamsetti
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, Germany.,Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, member of the DZL and CPI, Justus Liebig University, Giessen, Germany
| | - Argen Mamazhakypov
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, Germany
| | - Norbert Weissmann
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, member of the DZL and CPI, Justus Liebig University, Giessen, Germany
| | - Werner Seeger
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, Germany.,Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, member of the DZL and CPI, Justus Liebig University, Giessen, Germany.,Institute for Lung Health (ILH), Justus Liebig University, Giessen, Germany
| | - Rajkumar Savai
- Department of Lung Development and Remodeling, Max Planck Institute for Heart and Lung Research, member of the German Center for Lung Research (DZL), member of the Cardio-Pulmonary Institute (CPI), Bad Nauheim, Germany.,Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, member of the DZL and CPI, Justus Liebig University, Giessen, Germany.,Institute for Lung Health (ILH), Justus Liebig University, Giessen, Germany.,Frankfurt Cancer Institute (FCI), Goethe University, Frankfurt am Main, Germany
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24
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Matuleviciute R, Cunha PP, Johnson RS, Foskolou IP. Oxygen regulation of TET enzymes. FEBS J 2021; 288:7143-7161. [PMID: 33410283 DOI: 10.1111/febs.15695] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/23/2020] [Accepted: 01/04/2021] [Indexed: 12/15/2022]
Abstract
Hypoxia has a significant impact on many physiological and pathological processes. Over the recent years, its role in modulation of epigenetic remodelling has also become clearer. In cancer, low oxygen environments and aberrant epigenomes often go hand in hand, and changes in DNA methylation are now commonly recognised as potential outcome indicators. TET (ten-eleven translocation) family enzymes are alpha-ketoglutarate-, iron- and oxygen-dependent DNA demethylases and are key players in these processes. Although TETs have historically been considered tumour suppressors, recent studies suggest that their functions in cancer might not be straightforward. Recently, inhibition of TETs has been reported to have positive impact in cancer immunotherapy and vaccination studies. This underlines the current interest in developing targeted pharmaceutical inhibitors of these enzymes. Here, we will survey the complexity of TET roles in cancer, and its hypoxic modulation, as well as highlight the potential of these enzymes as therapeutic targets.
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Affiliation(s)
- Rugile Matuleviciute
- Department of Physiology, Development and Neuroscience, University of Cambridge, UK
| | - Pedro P Cunha
- Department of Physiology, Development and Neuroscience, University of Cambridge, UK
| | - Randall S Johnson
- Department of Physiology, Development and Neuroscience, University of Cambridge, UK.,Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Solna, Sweden
| | - Iosifina P Foskolou
- Department of Physiology, Development and Neuroscience, University of Cambridge, UK.,Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Solna, Sweden
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25
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Ortega-Sáenz P, Moreno-Domínguez A, Gao L, López-Barneo J. Molecular Mechanisms of Acute Oxygen Sensing by Arterial Chemoreceptor Cells. Role of Hif2α. Front Physiol 2020; 11:614893. [PMID: 33329066 PMCID: PMC7719705 DOI: 10.3389/fphys.2020.614893] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 11/03/2020] [Indexed: 01/28/2023] Open
Abstract
Carotid body glomus cells are multimodal arterial chemoreceptors able to sense and integrate changes in several physical and chemical parameters in the blood. These cells are also essential for O2 homeostasis. Glomus cells are prototypical peripheral O2 sensors necessary to detect hypoxemia and to elicit rapid compensatory responses (hyperventilation and sympathetic activation). The mechanisms underlying acute O2 sensing by glomus cells have been elusive. Using a combination of mouse genetics and single-cell optical and electrophysiological techniques, it has recently been shown that activation of glomus cells by hypoxia relies on the generation of mitochondrial signals (NADH and reactive oxygen species), which modulate membrane ion channels to induce depolarization, Ca2+ influx, and transmitter release. The special sensitivity of glomus cell mitochondria to changes in O2 tension is due to Hif2α-dependent expression of several atypical mitochondrial subunits, which are responsible for an accelerated oxidative metabolism and the strict dependence of mitochondrial complex IV activity on O2 availability. A mitochondrial-to-membrane signaling model of acute O2 sensing has been proposed, which explains existing data and provides a solid foundation for future experimental tests. This model has also unraveled new molecular targets for pharmacological modulation of carotid body activity potentially relevant in the treatment of highly prevalent medical conditions.
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Affiliation(s)
- Patricia Ortega-Sáenz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Alejandro Moreno-Domínguez
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain
| | - Lin Gao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, 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, Seville, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Seville, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
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26
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Kierans SJ, Taylor CT. Regulation of glycolysis by the hypoxia-inducible factor (HIF): implications for cellular physiology. J Physiol 2020; 599:23-37. [PMID: 33006160 DOI: 10.1113/jp280572] [Citation(s) in RCA: 379] [Impact Index Per Article: 94.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 09/25/2020] [Indexed: 12/22/2022] Open
Abstract
Under conditions of hypoxia, most eukaryotic cells can shift their primary metabolic strategy from predominantly mitochondrial respiration towards increased glycolysis to maintain ATP levels. This hypoxia-induced reprogramming of metabolism is key to satisfying cellular energetic requirements during acute hypoxic stress. At a transcriptional level, this metabolic switch can be regulated by several pathways including the hypoxia inducible factor-1α (HIF-1α) which induces an increased expression of glycolytic enzymes. While this increase in glycolytic flux is beneficial for maintaining bioenergetic homeostasis during hypoxia, the pathways mediating this increase can also be exploited by cancer cells to promote tumour survival and growth, an area which has been extensively studied. It has recently become appreciated that increased glycolytic metabolism in hypoxia may also have profound effects on cellular physiology in hypoxic immune and endothelial cells. Therefore, understanding the mechanisms central to mediating this reprogramming are of importance from both physiological and pathophysiological standpoints. In this review, we highlight the role of HIF-1α in the regulation of hypoxic glycolysis and its implications for physiological processes such as angiogenesis and immune cell effector function.
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Affiliation(s)
- S J Kierans
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, Ireland.,School of Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - C T Taylor
- Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, Ireland.,School of Medicine, University College Dublin, Belfield, Dublin, Ireland
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27
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Abstract
Investigations of the cellular and molecular mechanisms that mediate the development of the autonomic nervous system have identified critical genes and signaling pathways that, when disrupted, cause disorders of the autonomic nervous system. This review summarizes our current understanding of how the autonomic nervous system emerges from the organized spatial and temporal patterning of precursor cell migration, proliferation, communication, and differentiation, and discusses potential clinical implications for developmental disorders of the autonomic nervous system, including familial dysautonomia, Hirschsprung disease, Rett syndrome, and congenital central hypoventilation syndrome.
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Affiliation(s)
- Frances Lefcort
- Department of Cell Biology and Neuroscience, Montana State University, Bozeman, Montana
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28
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Hammarlund EU, Amend SR, Pienta KJ. The issues with tissues: the wide range of cell fate separation enables the evolution of multicellularity and cancer. Med Oncol 2020; 37:62. [PMID: 32535731 PMCID: PMC7293661 DOI: 10.1007/s12032-020-01387-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/03/2020] [Indexed: 12/24/2022]
Abstract
Our understanding of the rises of animal and cancer multicellularity face the same conceptual hurdles: what makes the clade originate and what makes it diversify. Between the events of origination and diversification lies complex tissue organization that gave rise to novel functionality for organisms and, unfortunately, for malignant transformation in cells. Tissue specialization with distinctly separated cell fates allowed novel functionality at organism level, such as for vertebrate animals, but also involved trade-offs at the cellular level that are potentially disruptive. These trade-offs are under-appreciated and here we discuss how the wide separation of cell phenotypes may contribute to cancer evolution by (a) how factors can reverse differentiated cells into a window of phenotypic plasticity, (b) the reversal to phenotypic plasticity coupled with asexual reproduction occurs in a way that the host cannot adapt, and (c) the power of the transformation factor correlates to the power needed to reverse tissue specialization. The role of reversed cell fate separation for cancer evolution is strengthened by how some tissues and organisms maintain high cell proliferation and plasticity without developing tumours at a corresponding rate. This demonstrates a potential proliferation paradox that requires further explanation. These insights from the cancer field, which observes tissue evolution in real time and closer than any other field, allow inferences to be made on evolutionary events in animal history. If a sweet spot of phenotypic and reproductive versatility is key to transformation, factors stimulating cell fate separation may have promoted also animal diversification on Earth.
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Affiliation(s)
- Emma U Hammarlund
- Translational Cancer Research, Department of Laboratory Medicine, Lund University, Lund, Sweden.
- Nordic Center for Earth Evolution, University of Southern Denmark, Odense, DK, Denmark.
| | - Sarah R Amend
- The Brady Urological Institute, Johns Hopkins School of Medicine, Baltimore, MD, 21287, USA
| | - Kenneth J Pienta
- The Brady Urological Institute, Johns Hopkins School of Medicine, Baltimore, MD, 21287, USA
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29
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Hammarlund EU. Harnessing hypoxia as an evolutionary driver of complex multicellularity. Interface Focus 2020; 10:20190101. [PMID: 32642048 DOI: 10.1098/rsfs.2019.0101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2020] [Indexed: 12/11/2022] Open
Abstract
Animal tissue requires low-oxygen conditions for its maintenance. The need for low-oxygen conditions contrasts with the idea of an evolutionary leap in animal diversity as a result of expanding oxic conditions. To accommodate tissue renewal at oxic conditions, however, vertebrate animals and vascular plants demonstrate abilities to access hypoxia. Here, I argue that multicellular organisms sustain oxic conditions first after internalizing hypoxic conditions. The 'harnessing' of hypoxia has allowed multicellular evolution to leave niches that were stable in terms of oxygen concentrations for those where oxygen fluctuates. Since oxygen fluctuates in most settings on Earth's surface, the ancestral niche would have been a deep marine setting. The hypothesis that 'large life' depends on harnessing hypoxia is illustrated in the context of conditions that promote the immature cell phenotype (stemness) in animal physiology and tumour biology and offers one explanation for the general rarity of diverse multicellularity over most of Earth's history.
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Affiliation(s)
- Emma U Hammarlund
- Department of Laboratory Medicine, Translational Cancer Research, Lund University, Scheelevägen 2, Medicon Village Building 404, 223 81 Lund, Sweden.,Department of Geology, Lund University, Sölvegatan 12, 223 62 Lund, Sweden
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30
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Abstract
Tibetans have adapted to the chronic hypoxia of high altitude and display a distinctive suite of physiologic adaptations, including augmented hypoxic ventilatory response and resistance to pulmonary hypertension. Genome-wide studies have consistently identified compelling genetic signatures of natural selection in two genes of the Hypoxia Inducible Factor pathway, PHD2 and HIF2A The product of the former induces the degradation of the product of the latter. Key issues regarding Tibetan PHD2 are whether it is a gain-of-function or loss-of-function allele, and how it might contribute to high-altitude adaptation. Tibetan PHD2 possesses two amino acid changes, D4E and C127S. We previously showed that in vitro, Tibetan PHD2 is defective in its interaction with p23, a cochaperone of the HSP90 pathway, and we proposed that Tibetan PHD2 is a loss-of-function allele. Here, we report that additional PHD2 mutations at or near Asp-4 or Cys-127 impair interaction with p23 in vitro. We find that mice with the Tibetan Phd2 allele display augmented hypoxic ventilatory response, supporting this loss-of-function proposal. This is phenocopied by mice with a mutation in p23 that abrogates the PHD2:p23 interaction. Hif2a haploinsufficiency, but not the Tibetan Phd2 allele, ameliorates hypoxia-induced increases in right ventricular systolic pressure. The Tibetan Phd2 allele is not associated with hemoglobin levels in mice. We propose that Tibetans possess genetic alterations that both activate and inhibit selective outputs of the HIF pathway to facilitate successful adaptation to the chronic hypoxia of high altitude.
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31
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Cheng X, Prange-Barczynska M, Fielding JW, Zhang M, Burrell AL, Lima JD, Eckardt L, Argles IL, Pugh CW, Buckler KJ, Robbins PA, Hodson EJ, Bruick RK, Collinson LM, Rastinejad F, Bishop T, Ratcliffe PJ. Marked and rapid effects of pharmacological HIF-2α antagonism on hypoxic ventilatory control. J Clin Invest 2020; 130:2237-2251. [PMID: 31999648 PMCID: PMC7190921 DOI: 10.1172/jci133194] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/14/2020] [Indexed: 12/22/2022] Open
Abstract
Hypoxia-inducible factor (HIF) is strikingly upregulated in many types of cancer, and there is great interest in applying inhibitors of HIF as anticancer therapeutics. The most advanced of these are small molecules that target the HIF-2 isoform through binding the PAS-B domain of HIF-2α. These molecules are undergoing clinical trials with promising results in renal and other cancers where HIF-2 is considered to be driving growth. Nevertheless, a central question remains as to whether such inhibitors affect physiological responses to hypoxia at relevant doses. Here, we show that pharmacological HIF-2α inhibition with PT2385, at doses similar to those reported to inhibit tumor growth, rapidly impaired ventilatory responses to hypoxia, abrogating both ventilatory acclimatization and carotid body cell proliferative responses to sustained hypoxia. Mice carrying a HIF-2α PAS-B S305M mutation that disrupts PT2385 binding, but not dimerization with HIF-1β, did not respond to PT2385, indicating that these effects are on-target. Furthermore, the finding of a hypomorphic ventilatory phenotype in untreated HIF-2α S305M mutant mice suggests a function for the HIF-2α PAS-B domain beyond heterodimerization with HIF-1β. Although PT2385 was well tolerated, the findings indicate the need for caution in patients who are dependent on hypoxic ventilatory drive.
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Affiliation(s)
- Xiaotong Cheng
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - Maria Prange-Barczynska
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | - James W. Fielding
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
| | | | | | | | | | | | | | - Keith J. Buckler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter A. Robbins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | | | - Richard K. Bruick
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | | | | | - Peter J. Ratcliffe
- Target Discovery Institute and
- Ludwig Institute for Cancer Research, University of Oxford, Oxford, United Kingdom
- Francis Crick Institute, London, United Kingdom
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32
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Macklin PS, Yamamoto A, Browning L, Hofer M, Adam J, Pugh CW. Recent advances in the biology of tumour hypoxia with relevance to diagnostic practice and tissue-based research. J Pathol 2020; 250:593-611. [PMID: 32086807 DOI: 10.1002/path.5402] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 02/18/2020] [Indexed: 02/06/2023]
Abstract
In this review article, we examine the importance of low levels of oxygen (hypoxia) in cancer biology. We provide a brief description of how mammalian cells sense oxygen. The hypoxia-inducible factor (HIF) pathway is currently the best characterised oxygen-sensing system, but recent work has revealed that mammals also use an oxygen-sensing system found in plants to regulate the abundance of some proteins and peptides with an amino-terminal cysteine residue. We discuss how the HIF pathway is affected during the growth of solid tumours, which develop in microenvironments with gradients of oxygen availability. We then introduce the concept of 'pseudohypoxia', a state of constitutive, oxygen-independent HIF system activation that occurs due to oncogenic stimulation in a number of specific tumour types that are of immediate relevance to diagnostic histopathologists. We provide an overview of the different methods of quantifying tumour hypoxia, emphasising the importance of pre-analytic factors in interpreting the results of tissue-based studies. Finally, we review recent approaches to targeting hypoxia/HIF system activation for therapeutic benefit, the application of which may require knowledge of which hypoxia signalling components are being utilised by a given tumour. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Philip S Macklin
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Atsushi Yamamoto
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Lisa Browning
- Department of Cellular Pathology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Monika Hofer
- Department of Neuropathology and Ocular Pathology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Julie Adam
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
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33
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Abstract
The carotid body (CB) is an arterial chemoreceptor organ located in the carotid bifurcation and has a well-recognized role in cardiorespiratory regulation. The CB contains neurosecretory sensory cells (glomus cells), which release transmitters in response to hypoxia, hypercapnia, and acidemia to activate afferent sensory fibers terminating in the respiratory and autonomic brainstem centers. Knowledge of the physiology of the CB has progressed enormously in recent years. Herein we review advances concerning the organization and function of the cellular elements of the CB, with emphasis on the molecular mechanisms of acute oxygen sensing by glomus cells. We introduce the modern view of the CB as a multimodal integrated metabolic sensor and describe the properties of the CB stem cell niche, which support CB growth during acclimatization to chronic hypoxia. Finally, we discuss the increasing medical relevance of CB dysfunction and its potential impact on the mechanisms of disease.
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Affiliation(s)
- Patricia Ortega-Sáenz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla 41013, Spain; , .,Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla 41009, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Sevilla 41013, Spain
| | - José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla 41013, Spain; , .,Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla 41009, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Sevilla 41013, Spain
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34
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Kameda Y. Molecular and cellular mechanisms of the organogenesis and development of the mammalian carotid body. Dev Dyn 2019; 249:592-609. [DOI: 10.1002/dvdy.144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 12/08/2019] [Accepted: 12/08/2019] [Indexed: 12/16/2022] Open
Affiliation(s)
- Yoko Kameda
- Department of AnatomyKitasato University School of Medicine Sagamihara Japan
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35
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Cummins EP, Strowitzki MJ, Taylor CT. Mechanisms and Consequences of Oxygen and Carbon Dioxide Sensing in Mammals. Physiol Rev 2019; 100:463-488. [PMID: 31539306 DOI: 10.1152/physrev.00003.2019] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Molecular oxygen (O2) and carbon dioxide (CO2) are the primary gaseous substrate and product of oxidative phosphorylation in respiring organisms, respectively. Variance in the levels of either of these gasses outside of the physiological range presents a serious threat to cell, tissue, and organism survival. Therefore, it is essential that endogenous levels are monitored and kept at appropriate concentrations to maintain a state of homeostasis. Higher organisms such as mammals have evolved mechanisms to sense O2 and CO2 both in the circulation and in individual cells and elicit appropriate corrective responses to promote adaptation to commonly encountered conditions such as hypoxia and hypercapnia. These can be acute and transient nontranscriptional responses, which typically occur at the level of whole animal physiology or more sustained transcriptional responses, which promote chronic adaptation. In this review, we discuss the mechanisms by which mammals sense changes in O2 and CO2 and elicit adaptive responses to maintain homeostasis. We also discuss crosstalk between these pathways and how they may represent targets for therapeutic intervention in a range of pathological states.
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Affiliation(s)
- Eoin P Cummins
- UCD Conway Institute, Systems Biology Ireland and the School of Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Moritz J Strowitzki
- UCD Conway Institute, Systems Biology Ireland and the School of Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Cormac T Taylor
- UCD Conway Institute, Systems Biology Ireland and the School of Medicine, University College Dublin, Belfield, Dublin, Ireland
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36
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Lindsey BG, Nuding SC, Segers LS, Morris KF. Carotid Bodies and the Integrated Cardiorespiratory Response to Hypoxia. Physiology (Bethesda) 2019; 33:281-297. [PMID: 29897299 DOI: 10.1152/physiol.00014.2018] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Advances in our understanding of brain mechanisms for the hypoxic ventilatory response, coordinated changes in blood pressure, and the long-term consequences of chronic intermittent hypoxia as in sleep apnea, such as hypertension and heart failure, are giving impetus to the search for therapies to "erase" dysfunctional memories distributed in the carotid bodies and central nervous system. We review current network models, open questions, sex differences, and implications for translational research.
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Affiliation(s)
- Bruce G Lindsey
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida , Tampa, Florida
| | - Sarah C Nuding
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida , Tampa, Florida
| | - Lauren S Segers
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida , Tampa, Florida
| | - Kendall F Morris
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida , Tampa, Florida
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Sobrino V, Annese V, Pardal R. Progenitor Cell Heterogeneity in the Adult Carotid Body Germinal Niche. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1123:19-38. [PMID: 31016593 DOI: 10.1007/978-3-030-11096-3_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Somatic stem cells confer plasticity to adult tissues, permitting their maintenance, repair and adaptation to a changing environment. Adult germinal niches supporting somatic stem cells have been thoroughly characterized throughout the organism, including in central and peripheral nervous systems. Stem cells do not reside alone within their niches, but they are rather accompanied by multiple progenitor cells that not only contribute to the progression of stem cell lineage but also regulate their behavior. Understanding the mechanisms underlying these interactions within the niche is crucial to comprehend associated pathologies and to use stem cells in cell therapy. We have described a stunning germinal niche in the adult peripheral nervous system: the carotid body. This is a chemoreceptor organ with a crucial function during physiological adaptation to hypoxia. We have shown the presence of multipotent stem cells within this niche, escorted by multiple restricted progenitor cell types that contribute to niche physiology and hence organismal adaptation to the lack of oxygen. Herein, we discuss new and existing data about the nature of all these stem and progenitor cell types present in the carotid body germinal niche, discussing their role in physiology and their clinical relevance for the treatment of diverse pathologies.
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Affiliation(s)
- Verónica Sobrino
- Dpto. de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Valentina Annese
- Dpto. de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Ricardo Pardal
- Dpto. de Fisiología Médica y Biofísica, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain.
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Urrutia AA, Aragonés J. HIF Oxygen Sensing Pathways in Lung Biology. Biomedicines 2018; 6:biomedicines6020068. [PMID: 29882755 PMCID: PMC6027477 DOI: 10.3390/biomedicines6020068] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 05/28/2018] [Accepted: 05/30/2018] [Indexed: 12/30/2022] Open
Abstract
Cellular responses to oxygen fluctuations are largely mediated by hypoxia-inducible factors (HIFs). Upon inhalation, the first organ inspired oxygen comes into contact with is the lungs, but the understanding of the pulmonary HIF oxygen-sensing pathway is still limited. In this review we will focus on the role of HIF1α and HIF2α isoforms in lung responses to oxygen insufficiency. In particular, we will discuss novel findings regarding their role in the biology of smooth muscle cells and endothelial cells in the context of hypoxia-induced pulmonary vasoconstriction. Moreover, we will also discuss recent studies into HIF-dependent responses in the airway epithelium, which have been even less studied than the HIF-dependent vascular responses in the lungs. In summary, we will review the biological functions executed by HIF1 or HIF2 in the pulmonary vessels and epithelium to control lung responses to oxygen fluctuations as well as their pathological consequences in the hypoxic lung.
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Affiliation(s)
- Andrés A Urrutia
- Research Unit, Hospital of Santa Cristina, Research Institute Princesa (IP), Autonomous University of Madrid, 28009 Madrid, Spain.
| | - Julián Aragonés
- Research Unit, Hospital of Santa Cristina, Research Institute Princesa (IP), Autonomous University of Madrid, 28009 Madrid, Spain.
- CIBER de Enfermedades Cardiovasculares, Carlos III Health Institute, 28029 Madrid, Spain.
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