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Koziol-White C, Gebski E, Cao G, Panettieri RA. Precision cut lung slices: an integrated ex vivo model for studying lung physiology, pharmacology, disease pathogenesis and drug discovery. Respir Res 2024; 25:231. [PMID: 38824592 PMCID: PMC11144351 DOI: 10.1186/s12931-024-02855-6] [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: 04/08/2024] [Accepted: 05/18/2024] [Indexed: 06/03/2024] Open
Abstract
Precision Cut Lung Slices (PCLS) have emerged as a sophisticated and physiologically relevant ex vivo model for studying the intricacies of lung diseases, including fibrosis, injury, repair, and host defense mechanisms. This innovative methodology presents a unique opportunity to bridge the gap between traditional in vitro cell cultures and in vivo animal models, offering researchers a more accurate representation of the intricate microenvironment of the lung. PCLS require the precise sectioning of lung tissue to maintain its structural and functional integrity. These thin slices serve as invaluable tools for various research endeavors, particularly in the realm of airway diseases. By providing a controlled microenvironment, precision-cut lung slices empower researchers to dissect and comprehend the multifaceted interactions and responses within lung tissue, thereby advancing our understanding of pulmonary pathophysiology.
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Affiliation(s)
- Cynthia Koziol-White
- Rutgers Institute for Translational Medicine and Science, The State University of NJ, 08901, Rutgers, New Brunswick, NJ, USA.
| | - Eric Gebski
- Rutgers Institute for Translational Medicine and Science, The State University of NJ, 08901, Rutgers, New Brunswick, NJ, USA
| | - Gaoyaun Cao
- Rutgers Institute for Translational Medicine and Science, The State University of NJ, 08901, Rutgers, New Brunswick, NJ, USA
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, The State University of NJ, 08901, Rutgers, New Brunswick, NJ, USA
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2
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Gao L, Ortega-Sáenz P, Moreno-Domínguez A, López-Barneo J. Mitochondrial Redox Signaling in O 2-Sensing Chemoreceptor Cells. Antioxid Redox Signal 2022; 37:274-289. [PMID: 35044243 DOI: 10.1089/ars.2021.0255] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Significance: Acute responses to hypoxia are essential for the survival of mammals. The carotid body (CB), the main arterial chemoreceptor, contains glomus cells with oxygen (O2)-sensitive K+ channels, which are inhibited during hypoxia to trigger adaptive cardiorespiratory reflexes. Recent Advances: In this review, recent advances in molecular mechanisms of acute O2 sensing in CB glomus cells are discussed, with a special focus on the signaling role of mitochondria through regulating cellular redox status. These advances have been achieved thanks to the use of genetically engineered redox-sensitive green fluorescent protein (roGFP) probes, which allowed us to monitor rapid changes in ROS production in real time in different subcellular compartments during hypoxia. This methodology was used in combination with conditional knockout mice models, pharmacological approaches, and transcriptomic studies. We have proposed a mitochondria-to-membrane signaling model of acute O2 sensing in which H2O2 released in the mitochondrial intermembrane space serves as a signaling molecule to inhibit K+ channels on the plasma membrane. Critical Issues: Changes in mitochondrial reactive oxygen species (ROS) production during acute hypoxia are highly compartmentalized in the submitochondrial regions. The use of redox-sensitive probes targeted to specific compartments is essential to fully understand the role of mitochondrial ROS in acute O2 sensing. Future Directions: Further studies are needed to specify the ROS and to characterize the target(s) of ROS in chemoreceptor cells during acute hypoxia. These data may also contribute to a more complete understanding of the implication of ROS in acute responses to hypoxia in O2-sensing cells in other organs. Antioxid. Redox Signal. 37, 274-289.
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Affiliation(s)
- 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
| | - 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.,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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3
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Maarman GJ. Reviewing the suitability of mitochondrial transplantation as therapeutic approach for pulmonary hypertension in the era of personalised medicine. Am J Physiol Lung Cell Mol Physiol 2022; 322:L641-L646. [PMID: 35318860 DOI: 10.1152/ajplung.00484.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pulmonary hypertension (PH) is a fatal disease, defined as a mean pulmonary artery pressure ≥ 25 mm Hg. It is caused, in part, by mitochondrial dysfunction. Among the various biological therapies proposed to rescue mitochondrial dysfunction, evidence going back as far as 2009, suggests that mitochondrial transplantation is an alternative. Although scant, recent PH findings and other literature supports a role for mitochondrial transplantation as a therapeutic approach in the context of PH. In experimental models of PH, it confers beneficial effects that include reduced pulmonary vasoconstriction, reduced pulmonary vascular remodelling, and improved right ventricular function. It also reduces the proliferation of pulmonary artery smooth muscle cells. However, first, we must understand that more research is needed before mitochondrial transplantation can be considered an effective therapy in the clinical setting, as many of the mechanisms or potential long-term risks are still unknown. Second, the current challenges of mitochondrial transplantation are surmountable and should not deter researchers from further investigating its effectiveness and trying to overcome these challenges in creative ways.
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Affiliation(s)
- Gerald J Maarman
- CARMA: Centre for Cardio-Metabolic Research in Africa, Division of Medical Physiology, Department of Biomedical Sciences, Stellenbosch University, Tygerberg, South Africa
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4
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Important Functions and Molecular Mechanisms of Mitochondrial Redox Signaling in Pulmonary Hypertension. Antioxidants (Basel) 2022; 11:antiox11030473. [PMID: 35326123 PMCID: PMC8944689 DOI: 10.3390/antiox11030473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 12/13/2022] Open
Abstract
Mitochondria are important organelles that act as a primary site to produce reactive oxygen species (ROS). Additionally, mitochondria play a pivotal role in the regulation of Ca2+ signaling, fatty acid oxidation, and ketone synthesis. Dysfunction of these signaling molecules leads to the development of pulmonary hypertension (PH), atherosclerosis, and other vascular diseases. Features of PH include vasoconstriction and pulmonary artery (PA) remodeling, which can result from abnormal proliferation, apoptosis, and migration of PA smooth muscle cells (PASMCs). These responses are mediated by increased Rieske iron–sulfur protein (RISP)-dependent mitochondrial ROS production and increased mitochondrial Ca2+ levels. Mitochondrial ROS and Ca2+ can both synergistically activate nuclear factor κB (NF-κB) to trigger inflammatory responses leading to PH, right ventricular failure, and death. Evidence suggests that increased mitochondrial ROS and Ca2+ signaling leads to abnormal synthesis of ketones, which play a critical role in the development of PH. In this review, we discuss some of the recent findings on the important interactive role and molecular mechanisms of mitochondrial ROS and Ca2+ in the development and progression of PH. We also address the contributions of NF-κB-dependent inflammatory responses and ketone-mediated oxidative stress due to abnormal regulation of mitochondrial ROS and Ca2+ signaling in PH.
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5
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Shihan M, Novoyatleva T, Lehmeyer T, Sydykov A, Schermuly RT. Role of the Purinergic P2Y2 Receptor in Pulmonary Hypertension. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182111009. [PMID: 34769531 PMCID: PMC8582672 DOI: 10.3390/ijerph182111009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 11/29/2022]
Abstract
Pulmonary arterial hypertension (PAH), group 1 pulmonary hypertension (PH), is a fatal disease that is characterized by vasoconstriction, increased pressure in the pulmonary arteries, and right heart failure. PAH can be described by abnormal vascular remodeling, hyperproliferation in the vasculature, endothelial cell dysfunction, and vascular tone dysregulation. The disease pathomechanisms, however, are as yet not fully understood at the molecular level. Purinergic receptors P2Y within the G-protein-coupled receptor family play a major role in fluid shear stress transduction, proliferation, migration, and vascular tone regulation in systemic circulation, but less is known about their contribution in PAH. Hence, studies that focus on purinergic signaling are of great importance for the identification of new therapeutic targets in PAH. Interestingly, the role of P2Y2 receptors has not yet been sufficiently studied in PAH, whereas the relevance of other P2Ys as drug targets for PAH was shown using specific agonists or antagonists. In this review, we will shed light on P2Y receptors and focus more on the P2Y2 receptor as a potential novel player in PAH and as a new therapeutic target for disease management.
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6
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Johnson DW, Roy TK, Secomb TW. Analysis of flow resistance in the pulmonary arterial circulation: implications for hypoxic pulmonary vasoconstriction. J Appl Physiol (1985) 2021; 131:1211-1218. [PMID: 34410848 DOI: 10.1152/japplphysiol.00128.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Hypoxic pulmonary vasoconstriction (HPV) plays an essential role in distributing blood in the lung to enhance ventilation-perfusion matching and blood oxygenation. In this study, a theoretical model of the pulmonary vasculature is used to predict the effects of vasoconstriction over specified ranges of vessel diameters on pulmonary vascular resistance (PVR). The model is used to evaluate the ability of hypothesized mechanisms of HPV to account for observed levels of PVR elevation during hypoxia. The vascular structure from pulmonary arteries to capillaries is represented using scaling laws. Vessel segments are modeled as resistive elements and blood flow rates are computed from physical principles. Direct vascular responses to intravascular oxygen levels have been proposed as a mechanism of HPV. In the lung, significant changes in oxygen level occur only in vessels less than 60 μm in diameter. The model shows that observed levels of hypoxic vasoconstriction in these vessels alone cannot account for the elevation of PVR associated with HPV. However, the elevation in PVR associated with HPV can be accounted for if larger upstream vessels also constrict. These results imply that upstream signaling by conducted responses to engage constriction of arterioles plays an essential role in the elevation of PVR during HPV.NEW & NOTEWORTHY A theoretical model of the pulmonary vasculature is used to predict the effects of vasoconstriction over specified ranges of vessel diameters on pulmonary vascular resistance (PVR). The model shows that observed levels of hypoxic vasoconstriction in terminal vessels cannot account for the elevation of PVR associated with hypoxic pulmonary vasoconstriction (HPV). Upstream signaling by conducted responses to engage constriction of arterioles, therefore, plays an essential role in the elevation of PVR during HPV.
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Affiliation(s)
- David W Johnson
- Physiological Sciences Graduate Program, University of Arizona, Tucson, Arizona
| | - Tuhin K Roy
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota
| | - Timothy W Secomb
- Physiological Sciences Graduate Program, University of Arizona, Tucson, Arizona.,Department of Physiology, University of Arizona, Tucson, Arizona
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7
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Coburn RF. Coronary and cerebral metabolism-blood flow coupling and pulmonary alveolar ventilation-blood flow coupling may be disabled during acute carbon monoxide poisoning. J Appl Physiol (1985) 2020; 129:1039-1050. [PMID: 32853110 DOI: 10.1152/japplphysiol.00172.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Current evidence indicates that the toxicity of carbon monoxide (CO) poisoning results from increases in reactive oxygen species (ROS) generation plus tissue hypoxia resulting from decreases in capillary Po2 evoked by effects of increases in blood [carboxyhemoglobin] on the oxyhemoglobin dissociation curve. There has not been consideration of how increases in Pco could influence metabolism-blood flow coupling, a physiological mechanism that regulates the uniformity of tissue Po2, and alveolar ventilation-blood flow coupling, a mechanism that increases the efficiency of pulmonary O2 uptake. Using published data, I consider hypotheses that these coupling mechanisms, triggered by O2 and CO sensors located in arterial and arteriolar vessels in the coronary and cerebral circulations and in lung intralobar arteries, are disrupted during acute CO poisoning. These hypotheses are supported by calculations that show that the Pco in these vessels can reach levels during CO poisoning that would exert effects on signal transduction molecules involved in these coupling mechanisms.NEW & NOTEWORTHY This article introduces and supports a postulate that the tissue hypoxia component of carbon monoxide poisoning results in part from impairment of physiological adaptation mechanisms whereby tissues can match regional blood flow to O2 uptake, and the lung can match regional blood flow to alveolar ventilation.
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Affiliation(s)
- Ronald F Coburn
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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8
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Murtaza G, Paddenberg R, Pfeil U, Goldenberg A, Mermer P, Kummer W. Hypoxia-induced pulmonary vasoconstriction of intra-acinar arteries is impaired in NADPH oxidase 4 gene-deficient mice. Pulm Circ 2018; 8:2045894018808240. [PMID: 30284509 PMCID: PMC6236867 DOI: 10.1177/2045894018808240] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We show that genetic deficiency of the reactive oxygen species generating enzyme
NADPH oxidase 4 (NOX4) impairs hypoxic pulmonary vasoconstriction in small
(25–40 µm) intra-acinar, but not pre-acinar, arteries in murine precision cut
lung slices. These data suggest an involvement of NOX4 in ventilation-perfusion
matching at the acinar level.
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Affiliation(s)
- Ghulam Murtaza
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany.,2 Department of Zoology, University of Gujrat, Gujrat, Pakistan
| | - Renate Paddenberg
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Uwe Pfeil
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Anna Goldenberg
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Petra Mermer
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Wolfgang Kummer
- 1 Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany.,3 German Center for Lung Research, Excellence Cluster Cardio-Pulmonary System, Justus-Liebig-University, Giessen, Germany
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9
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Chottova Dvorakova M, Mistrova E, Paddenberg R, Kummer W, Slavikova J. Substance P Receptor in the Rat Heart and Regulation of Its Expression in Long-Term Diabetes. Front Physiol 2018; 9:918. [PMID: 30057556 PMCID: PMC6053525 DOI: 10.3389/fphys.2018.00918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 06/25/2018] [Indexed: 11/13/2022] Open
Abstract
Substance P (SP) is a neuropeptide engaged in the signal transmission of neural C fibers afferents in the myocardium. The actions of SP in the heart are extensive and they are mediated by the neurokinin 1 receptor (NK1R), a member of the tachykinin subfamily of G-protein coupled receptors. The receptors have been found in the heart, but to our knowledge, their exact localization in the heart has not been described yet. Here, we investigated the presence of NK1R protein in separate rat heart compartments by means of western blot and its tissue distribution by means of immunofluorescence. Specificity of NK1R immunolabeling was controlled by preabsorption of the antiserum with its corresponding peptide. Additionally, we investigated abundance of gene for NK1R in separated heart chambers by means of quantitative real-time PCR (RT-PCR). Relative abundance of NK1R mRNA was expressed as a ratio of target gene Cq value to Cq value of control gene - beta-actin. Finally, we studied abundance of NK1R mRNA in different cell types of heart isolated by laser capture microdissection. Immunofluorescence showed NK1R immunoreactivity on the surface of some intracardiac neurons and smooth muscle cells of coronary vessels. The results of quantitative RT-PCR indicate abundance of mRNA for NK1R in all heart chambers with highest level in the left atrium. The presence of NK1R mRNA was detected in some samples of dissected intracardiac neurons, but not in cardiomyocytes or smooth muscle cells of coronary vessels. In the course of long-term diabetes, a significant downregulation of the NK1R mRNA was seen in the right atrium and upregulation in the right ventricle 53 weeks after the induction of diabetes. Our results indicate localization of NK1R in some intracardiac neurons and smooth muscle cells. Impaired transcription of the NK1R gene in the diabetic heart may be induced by unidentified genes or factors involved in the development of diabetic cardiomyopathy.
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Affiliation(s)
- Magdalena Chottova Dvorakova
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia.,Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Eliska Mistrova
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia.,Department of Physiology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
| | - Renate Paddenberg
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Wolfgang Kummer
- Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Jana Slavikova
- Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czechia
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Strielkov I, Krause NC, Sommer N, Schermuly RT, Ghofrani HA, Grimminger F, Gudermann T, Dietrich A, Weissmann N. Hypoxic pulmonary vasoconstriction in isolated mouse pulmonary arterial vessels. Exp Physiol 2018; 103:1185-1191. [PMID: 29917290 DOI: 10.1113/ep087117] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 06/04/2018] [Indexed: 12/24/2022]
Abstract
NEW FINDINGS What is the central question of this study? Hypoxic pulmonary vasoconstriction has never been characterized in isolated mouse pulmonary arteries of different generations in detail. What is the main finding and its importance? We found that only small intrapulmonary arteries (80-200 μm in diameter) exhibit hypoxic pulmonary vasoconstriction. The observed response was sustained, significantly potentiated by depolarization-induced preconstriction and not dependent on the endothelium or TRPC6 channels. ABSTRACT Hypoxic pulmonary vasoconstriction (HPV) is a physiological response of pulmonary arteries, which adapts lung perfusion to regional ventilation. The properties of HPV vary significantly between animal species. Despite extensive use of mouse models in studies of HPV, this physiological response has never been characterized in isolated mouse pulmonary arteries in detail. Using wire myography, we investigated the effect of 80 min exposure to hypoxia on the tone in mouse pulmonary arteries of different generations in the presence and absence of preconstriction. Hypoxia induced a sustained relaxation in non-preconstricted extrapulmonary arteries (500-700 μm in diameter), but not in the presence of KCl-induced preconstriction. Large intrapulmonary arteries (450-650 μm in diameter) did not exhibit a significant response to the hypoxic challenge. In contrast, in small intrapulmonary arteries (80-200 μm in diameter), hypoxia elicited a slowly developing sustained constriction, which was independent of the endothelium. The response was significantly potentiated in arteries preconstricted with KCl, but not with U46619. Hypoxic pulmonary vasoconstriction was not altered in pulmonary arteries of TRPC6-deficient mice, which suggests that this response corresponds to the sustained phase of biphasic HPV observed earlier in isolated, buffer-perfused and ventilated mouse lungs. In conclusion, we have established a protocol that allows the study of sustained HPV in isolated mouse pulmonary arteries. The data obtained might be useful for future studies of the mechanisms of HPV in mice.
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Affiliation(s)
- Ievgen Strielkov
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Nicole Catherine Krause
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Natascha Sommer
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Ralph Theo Schermuly
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Hossein Ardeschir Ghofrani
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Friedrich Grimminger
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig Maximilian University Munich, Munich, Germany.,German Center for Lung Research, Munich, Germany.,German Centre for Cardiovascular Research, Munich Heart Alliance, Munich, Germany
| | - Alexander Dietrich
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig Maximilian University Munich, Munich, Germany.,German Center for Lung Research, Munich, Germany
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System, German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
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11
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Gao L, Bonilla-Henao V, García-Flores P, Arias-Mayenco I, Ortega-Sáenz P, López-Barneo J. Gene expression analyses reveal metabolic specifications in acute O 2 -sensing chemoreceptor cells. J Physiol 2017; 595:6091-6120. [PMID: 28718507 DOI: 10.1113/jp274684] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/03/2017] [Indexed: 01/05/2023] Open
Abstract
KEY POINTS Glomus cells in the carotid body (CB) and chromaffin cells in the adrenal medulla (AM) are essential for reflex cardiorespiratory adaptation to hypoxia. However, the mechanisms whereby these cells detect changes in O2 tension are poorly understood. The metabolic properties of acute O2 -sensing cells have been investigated by comparing the transcriptomes of CB and AM cells, which are O2 -sensitive, with superior cervical ganglion neurons, which are practically O2 -insensitive. In O2 -sensitive cells, we found a characteristic prolyl hydroxylase 3 down-regulation and hypoxia inducible factor 2α up-regulation, as well as overexpression of genes coding for three atypical mitochondrial electron transport subunits and pyruvate carboxylase, an enzyme that replenishes tricarboxylic acid cycle intermediates. In agreement with this observation, the inhibition of succinate dehydrogenase impairs CB acute O2 sensing. The responsiveness of peripheral chemoreceptor cells to acute hypoxia depends on a 'signature metabolic profile'. ABSTRACT Acute O2 sensing is a fundamental property of cells in the peripheral chemoreceptors, e.g. glomus cells in the carotid body (CB) and chromaffin cells in the adrenal medulla (AM), and is necessary for adaptation to hypoxia. These cells contain O2 -sensitive ion channels, which mediate membrane depolarization and transmitter release upon exposure to hypoxia. However, the mechanisms underlying the detection of changes in O2 tension by cells are still poorly understood. Recently, we suggested that CB glomus cells have specific metabolic features that favour the accumulation of reduced quinone and the production of mitochondrial NADH and reactive oxygen species during hypoxia. These signals alter membrane ion channel activity. To investigate the metabolic profile characteristic of acute O2 -sensing cells, we used adult mice to compare the transcriptomes of three cell types derived from common sympathoadrenal progenitors, but exhibiting variable responsiveness to acute hypoxia: CB and AM cells, which are O2 -sensitive (glomus cells > chromaffin cells), and superior cervical ganglion neurons, which are practically O2 -insensitive. In the O2 -sensitive cells, we found a characteristic mRNA expression pattern of prolyl hydroxylase 3/hypoxia inducible factor 2α and up-regulation of several genes, in particular three atypical mitochondrial electron transport subunits and some ion channels. In addition, we found that pyruvate carboxylase, an enzyme fundamental to tricarboxylic acid cycle anaplerosis, is overexpressed in CB glomus cells. We also observed that the inhibition of succinate dehydrogenase impairs CB acute O2 sensing. Our data suggest that responsiveness to acute hypoxia depends on a 'signature metabolic profile' in chemoreceptor cells.
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Affiliation(s)
- Lin Gao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Victoria Bonilla-Henao
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Paula García-Flores
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Ignacio Arias-Mayenco
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Patricia Ortega-Sáenz
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - José López-Barneo
- Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.,Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Spain
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12
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McElroy GS, Chandel NS. Mitochondria control acute and chronic responses to hypoxia. Exp Cell Res 2017; 356:217-222. [PMID: 28327410 DOI: 10.1016/j.yexcr.2017.03.034] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Accepted: 03/16/2017] [Indexed: 12/30/2022]
Abstract
There are numerous mechanisms by which mammals respond to hypoxia. These include acute changes in pulmonary arterial tone due to smooth muscle cell contraction, acute increases in respiration triggered by the carotid body chemosensory cells, and chronic changes such as induction of red blood cell proliferation and angiogenesis by hypoxia inducible factor targets erythropoietin and vascular endothelial growth factor, respectively. Mitochondria account for the majority of oxygen consumption in the cell and have recently been appreciated to serve as signaling organelles required for the initiation or propagation of numerous homeostatic mechanisms. Mitochondria can influence cell signaling by production of reactive oxygen species and metabolites. Here we review recent evidence that mitochondrial signals can imitate acute and chronic hypoxia responses.
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Affiliation(s)
- G S McElroy
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, United States
| | - N S Chandel
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, United States.
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Murtaza G, Mermer P, Goldenberg A, Pfeil U, Paddenberg R, Weissmann N, Lochnit G, Kummer W. TASK-1 potassium channel is not critically involved in mediating hypoxic pulmonary vasoconstriction of murine intra-pulmonary arteries. PLoS One 2017; 12:e0174071. [PMID: 28301582 PMCID: PMC5354433 DOI: 10.1371/journal.pone.0174071] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 03/02/2017] [Indexed: 11/26/2022] Open
Abstract
The two-pore domain potassium channel KCNK3 (TASK-1) is expressed in rat and human pulmonary artery smooth muscle cells. There, it is associated with hypoxia-induced signalling, and its dysfunction is linked to pathogenesis of human pulmonary hypertension. We here aimed to determine its role in hypoxic pulmonary vasoconstriction (HPV) in the mouse, and hence the suitability of this model for further mechanistic investigations, using appropriate inhibitors and TASK-1 knockout (KO) mice. RT-PCR revealed expression of TASK-1 mRNA in murine lungs and pre-acinar pulmonary arteries. Protein localization by immunohistochemistry and western blot was unreliable since all antibodies produced labelling also in TASK-1 KO organs/tissues. HPV was investigated by videomorphometric analysis of intra- (inner diameter: 25–40 μm) and pre-acinar pulmonary arteries (inner diameter: 41–60 μm). HPV persisted in TASK-1 KO intra-acinar arteries. Pre-acinar arteries developed initial HPV, but the response faded earlier (after 30 min) in KO vessels. This HPV pattern was grossly mimicked by the TASK-1 inhibitor anandamide in wild-type vessels. Hypoxia-provoked rise in pulmonary arterial pressure (PAP) in isolated ventilated lungs was affected neither by TASK-1 gene deficiency nor by the TASK-1 inhibitor A293. TASK-1 is dispensable for initiating HPV of murine intra-pulmonary arteries, but participates in sustained HPV specifically in pre-acinar arteries. This does not translate into abnormal rise in PAP. While there is compelling evidence that TASK-1 is involved in the pathogenesis of pulmonary arterial hypertension in humans, the mouse does not appear to serve as a suitable model to study the underlying molecular mechanisms.
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Affiliation(s)
- Ghulam Murtaza
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
- * E-mail:
| | - Petra Mermer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Anna Goldenberg
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Uwe Pfeil
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Renate Paddenberg
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Nobert Weissmann
- Universities of Giessen and Marburg Lung Center, Justus-Liebig-University, Giessen, Germany
- German Center for Lung Research, Excellence Cluster Cardio-Pulmonary System, Justus-Liebig-University, Giessen, Germany
| | - Guenter Lochnit
- Institute of Biochemistry, Faculty of Medicine, Justus-Liebig University, Giessen, Germany
| | - Wolfgang Kummer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
- German Center for Lung Research, Excellence Cluster Cardio-Pulmonary System, Justus-Liebig-University, Giessen, Germany
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14
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Hancock CN, Liu W, Alvord WG, Phang JM. Co-regulation of mitochondrial respiration by proline dehydrogenase/oxidase and succinate. Amino Acids 2015; 48:859-872. [PMID: 26660760 PMCID: PMC4752965 DOI: 10.1007/s00726-015-2134-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 11/05/2015] [Indexed: 02/03/2023]
Abstract
Proline dehydrogenase/oxidase (PRODH/POX) is a mitochondrial protein critical to multiple stress pathways. Because of the roles of PRODH/POX in signaling, and its shared localization to the mitochondrial inner membrane with the electron transport chain (ETC), we investigated whether there was a direct relationship between PRODH/POX and regulation of the ETC. We found that PRODH/POX binds directly to CoQ1 and that CoQ1-dependent PRODH/POX activity required functional Complex III and Complex IV. PRODH/POX supported respiration in living cells during nutrient stress; however, expression of PRODH/POX resulted in an overall decrease in respiratory fitness. Effects on respiratory fitness were inhibited by DHP and NAC, indicating that these effects were mediated by PRODH/POX-dependent reactive oxygen species (ROS) generation. PRODH/POX expression resulted in a dose-dependent down-regulation of Complexes I–IV of the ETC, and this effect was also mitigated by the addition of DHP and NAC. We found that succinate was an uncompetitive inhibitor of PRODH/POX activity, inhibited ROS generation by PRODH/POX, and alleviated PRODH/POX effects on respiratory fitness. The findings demonstrate novel cross-talk between proline and succinate respiration in vivo and provide mechanistic insights into observations from previous animal studies. Our results suggest a potential regulatory loop between PRODH/POX and succinate in regulation of mitochondrial respiration.
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Affiliation(s)
- Chad N Hancock
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, NCI-Frederick, 1050 Boyles Street, Bldg. 538, Rm. 144, Frederick, MD, 21702-1201, USA.
| | - Wei Liu
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, NCI-Frederick, 1050 Boyles Street, Bldg. 538, Rm. 144, Frederick, MD, 21702-1201, USA
| | - W Gregory Alvord
- Data Management Services, National Cancer Institute at Frederick, Frederick, MD, 21702, USA
| | - James M Phang
- Metabolism and Cancer Susceptibility Section, Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, NCI-Frederick, 1050 Boyles Street, Bldg. 538, Rm. 144, Frederick, MD, 21702-1201, USA.
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15
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Diehl J, Gries B, Pfeil U, Goldenberg A, Mermer P, Kummer W, Paddenberg R. Expression and localization of GPR91 and GPR99 in murine organs. Cell Tissue Res 2015; 364:245-62. [DOI: 10.1007/s00441-015-2318-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 10/21/2015] [Indexed: 10/22/2022]
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16
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Sommer N, Strielkov I, Pak O, Weissmann N. Oxygen sensing and signal transduction in hypoxic pulmonary vasoconstriction. Eur Respir J 2015; 47:288-303. [PMID: 26493804 DOI: 10.1183/13993003.00945-2015] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/24/2015] [Indexed: 01/17/2023]
Abstract
Hypoxic pulmonary vasoconstriction (HPV), also known as the von Euler-Liljestrand mechanism, is an essential response of the pulmonary vasculature to acute and sustained alveolar hypoxia. During local alveolar hypoxia, HPV matches perfusion to ventilation to maintain optimal arterial oxygenation. In contrast, during global alveolar hypoxia, HPV leads to pulmonary hypertension. The oxygen sensing and signal transduction machinery is located in the pulmonary arterial smooth muscle cells (PASMCs) of the pre-capillary vessels, albeit the physiological response may be modulated in vivo by the endothelium. While factors such as nitric oxide modulate HPV, reactive oxygen species (ROS) have been suggested to act as essential mediators in HPV. ROS may originate from mitochondria and/or NADPH oxidases but the exact oxygen sensing mechanisms, as well as the question of whether increased or decreased ROS cause HPV, are under debate. ROS may induce intracellular calcium increase and subsequent contraction of PASMCs via direct or indirect interactions with protein kinases, phospholipases, sarcoplasmic calcium channels, transient receptor potential channels, voltage-dependent potassium channels and L-type calcium channels, whose relevance may vary under different experimental conditions. Successful identification of factors regulating HPV may allow development of novel therapeutic approaches for conditions of disturbed HPV.
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Affiliation(s)
- Natascha Sommer
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany
| | - Ievgen Strielkov
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany
| | - Oleg Pak
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System, University of Giessen Lung Center, German Center for Lung Research (DZL), Justus-Liebig-University, Giessen, Germany
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Rommel FR, Raghavan B, Paddenberg R, Kummer W, Tumala S, Lochnit G, Gieler U, Peters EMJ. Suitability of Nicotinic Acetylcholine Receptor α7 and Muscarinic Acetylcholine Receptor 3 Antibodies for Immune Detection: Evaluation in Murine Skin. J Histochem Cytochem 2015; 63:329-39. [PMID: 25673288 DOI: 10.1369/0022155415575028] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/23/2015] [Indexed: 12/31/2022] Open
Abstract
Recent evidence reveals a crucial role for acetylcholine and its receptors in the regulation of inflammation, particularly of nicotinic acetylcholine receptor α7 (Chrna7) and muscarinic acetylcholine receptor 3 (Chrm3). Immunohistochemistry is a key tool for their cellular localization in functional tissues. We evaluated nine different commercially available antibodies on back skin tissue from wild-type (Wt) and gene-deficient (KO) mice. In the immunohistochemical analysis, we focused on key AChR-ligand sensitive skin cells (mast cells, nerve fibers and keratinocytes). All five antibodies tested for Chrm3 and the first three Chrna7 antibodies stained positive in both Wt and respective KO skin. With the 4th antibody (ab23832) nerve fibers were unlabeled in the KO mice. By western blot analysis, this antibody detected bands in both Wt and Chrna7 KO skin and brain. qRT-PCR revealed mRNA amplification with a primer set for the undeleted region in both Wt and KO mice, but none with a primer set for the deleted region in KO mice. By 2D electrophoresis, we found β-actin and β-enolase cross reactivity, which was confirmed by double immunolabeling. In view of the present results, the tested antibodies are not suitable for immunolocalization in skin and suggest thorough control of antibody specificity is required if histomorphometry is intended.
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Affiliation(s)
- Frank R Rommel
- Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy (FRR, BR, ST, EMJP)
| | - Badrinarayanan Raghavan
- Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy (FRR, BR, ST, EMJP)
| | - Renate Paddenberg
- Institute of Anatomy and Cell Biology, Justus Liebig University, Giessen, Germany (RP, WK)
| | - Wolfgang Kummer
- Institute of Anatomy and Cell Biology, Justus Liebig University, Giessen, Germany (RP, WK)
| | - Susanne Tumala
- Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy (FRR, BR, ST, EMJP)
| | - Günter Lochnit
- Institute of Biochemistry, Justus Liebig University, Giessen, Germany (GL)
| | - Uwe Gieler
- Department of Dermatology, University Hospital Giessen, Giessen, Germany (UG)
| | - Eva M J Peters
- Psychoneuroimmunology Laboratory, Department of Psychosomatic Medicine and Psychotherapy (FRR, BR, ST, EMJP),Charité Center 12 for Internal Medicine and Dermatology, Universitätsmedizin Charité, Berlin, Germany (EMJP)
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Paddenberg R, Mermer P, Goldenberg A, Kummer W. Videomorphometric analysis of hypoxic pulmonary vasoconstriction of intra-pulmonary arteries using murine precision cut lung slices. J Vis Exp 2014:e50970. [PMID: 24458260 PMCID: PMC4089409 DOI: 10.3791/50970] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Acute alveolar hypoxia causes pulmonary vasoconstriction (HPV) - also known as von Euler-Liljestrand mechanism - which serves to match lung perfusion to ventilation. Up to now, the underlying mechanisms are not fully understood. The major vascular segment contributing to HPV is the intra-acinar artery. This vessel section is responsible for the blood supply of an individual acinus, which is defined as the portion of lung distal to a terminal bronchiole. Intra-acinar arteries are mostly located in that part of the lung that cannot be selectively reached by a number of commonly used techniques such as measurement of the pulmonary artery pressure in isolated perfused lungs or force recordings from dissected proximal pulmonary artery segments(1,2). The analysis of subpleural vessels by real-time confocal laser scanning luminescence microscopy is limited to vessels with up to 50 µm in diameter(3). We provide a technique to study HPV of murine intra-pulmonary arteries in the range of 20-100 µm inner diameters. It is based on the videomorphometric analysis of cross-sectioned arteries in precision cut lung slices (PCLS). This method allows the quantitative measurement of vasoreactivity of small intra-acinar arteries with inner diameter between 20-40 µm which are located at gussets of alveolar septa next to alveolar ducts and of larger pre-acinar arteries with inner diameters between 40-100 µm which run adjacent to bronchi and bronchioles. In contrast to real-time imaging of subpleural vessels in anesthetized and ventilated mice, videomorphometric analysis of PCLS occurs under conditions free of shear stress. In our experimental model both arterial segments exhibit a monophasic HPV when exposed to medium gassed with 1% O2 and the response fades after 30-40 min at hypoxia.
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Affiliation(s)
| | - Petra Mermer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University
| | - Anna Goldenberg
- Institute of Anatomy and Cell Biology, Justus-Liebig-University
| | - Wolfgang Kummer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University
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Voelkel NF, Bogaard HJ, Al Husseini A, Farkas L, Gomez-Arroyo J, Natarajan R. Antioxidants for the treatment of patients with severe angioproliferative pulmonary hypertension? Antioxid Redox Signal 2013; 18:1810-7. [PMID: 22870869 DOI: 10.1089/ars.2012.4828] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
SIGNIFICANCE Pathobiological mechanisms that contribute to pulmonary vasoconstriction, lung vascular remodeling, and the development of right heart failure include the generation of reactive oxygen and nitrogen species and the response of lung vascular and cardiac cells to these molecules. We review the information regarding oxidant stress balanced by antioxidant mechanisms and the role of oxidants and antioxidants in hypoxic pulmonary hypertension and their potential role in an animal model of severe pulmonary arterial hypertension (PAH). RECENT ADVANCES In human lung tissue from patients with idiopathic PAH, we find reduced superoxide dismutase activity and high expression of the oxidant stress markers nitrotyrosine and 8-OH-guanosine. In the Sugen 5416/chronic hypoxia model of PAH, lung tissue expression of nitrotyrosine and hemeoxygenase 1 (HO-1) is substantial, while HO-1 expression in the failing right ventricle is decreased. This model, based on administration of the VEGF receptor blocker Sugen 5416 and chronic hypoxia (Su/Hx), reproduces many of the characteristic features of severe angioobliterative human PAH. Treatment of Su/Hx rats with protandim, which nuclear factor erythroid-2 related factor (Nrf2)-dependently upregulates the expression of genes encoding antioxidant enzymes, protects against right heart failure without affecting angioobliterative PAH. CRITICAL ISSUES In human severe PAH, patient survival is determined by the function of the stressed right ventricle; investigation of oxidative and nitrosative stresses and their potential contribution to right heart failure is necessary. FUTURE DIRECTIONS Antioxidant therapeutic strategies may be of benefit in the setting of human severe PAH. Whether antioxidant strategies affect lung vascular remodeling and/or prevent right heart failure remains to be examined.
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Affiliation(s)
- Norbert F Voelkel
- Victoria Johnson Center for Lung Research, Virginia Commonwealth University, Richmond, VA 23298, USA.
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Cahill E, Rowan SC, Sands M, Banahan M, Ryan D, Howell K, McLoughlin P. The pathophysiological basis of chronic hypoxic pulmonary hypertension in the mouse: vasoconstrictor and structural mechanisms contribute equally. Exp Physiol 2012; 97:796-806. [DOI: 10.1113/expphysiol.2012.065474] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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