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Balczon R, Lin MT, Voth S, Nelson AR, Schupp JC, Wagener BM, Pittet JF, Stevens T. Lung endothelium, tau, and amyloids in health and disease. Physiol Rev 2024; 104:533-587. [PMID: 37561137 DOI: 10.1152/physrev.00006.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/26/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023] Open
Abstract
Lung endothelia in the arteries, capillaries, and veins are heterogeneous in structure and function. Lung capillaries in particular represent a unique vascular niche, with a thin yet highly restrictive alveolar-capillary barrier that optimizes gas exchange. Capillary endothelium surveys the blood while simultaneously interpreting cues initiated within the alveolus and communicated via immediately adjacent type I and type II epithelial cells, fibroblasts, and pericytes. This cell-cell communication is necessary to coordinate the immune response to lower respiratory tract infection. Recent discoveries identify an important role for the microtubule-associated protein tau that is expressed in lung capillary endothelia in the host-pathogen interaction. This endothelial tau stabilizes microtubules necessary for barrier integrity, yet infection drives production of cytotoxic tau variants that are released into the airways and circulation, where they contribute to end-organ dysfunction. Similarly, beta-amyloid is produced during infection. Beta-amyloid has antimicrobial activity, but during infection it can acquire cytotoxic activity that is deleterious to the host. The production and function of these cytotoxic tau and amyloid variants are the subject of this review. Lung-derived cytotoxic tau and amyloid variants are a recently discovered mechanism of end-organ dysfunction, including neurocognitive dysfunction, during and in the aftermath of infection.
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Affiliation(s)
- Ron Balczon
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Mike T Lin
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Sarah Voth
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Monroe, Louisiana, United States
| | - Amy R Nelson
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Jonas C Schupp
- Pulmonary and Critical Care Medicine, Department of Internal Medicine, Yale University, New Haven, Connecticut, United States
- Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
- German Center for Lung Research (DZL), Hannover, Germany
| | - Brant M Wagener
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Jean-Francois Pittet
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Troy Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Department of Internal Medicine, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
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2
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Lee JY, Stevens RP, Pastukh VV, Pastukh VM, Kozhukhar N, Alexeyev MF, Reisz JA, Nerguizian D, D’Alessandro A, Koloteva A, Gwin MS, Roberts JT, Borchert GM, Wagener BM, Pittet JF, Graham BB, Stenmark KR, Stevens T. PFKFB3 Inhibits Fructose Metabolism in Pulmonary Microvascular Endothelial Cells. Am J Respir Cell Mol Biol 2023; 69:340-354. [PMID: 37201952 PMCID: PMC10503305 DOI: 10.1165/rcmb.2022-0443oc] [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: 11/13/2022] [Accepted: 05/17/2023] [Indexed: 05/20/2023] Open
Abstract
Pulmonary microvascular endothelial cells contribute to the integrity of the lung gas exchange interface, and they are highly glycolytic. Although glucose and fructose represent discrete substrates available for glycolysis, pulmonary microvascular endothelial cells prefer glucose over fructose, and the mechanisms involved in this selection are unknown. 6-Phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 3 (PFKFB3) is an important glycolytic enzyme that drives glycolytic flux against negative feedback and links glycolytic and fructolytic pathways. We hypothesized that PFKFB3 inhibits fructose metabolism in pulmonary microvascular endothelial cells. We found that PFKFB3 knockout cells survive better than wild-type cells in fructose-rich medium under hypoxia. Seahorse assays, lactate and glucose measurements, and stable isotope tracing showed that PFKFB3 inhibits fructose-hexokinase-mediated glycolysis and oxidative phosphorylation. Microarray analysis revealed that fructose upregulates PFKFB3, and PFKFB3 knockout cells increase fructose-specific GLUT5 (glucose transporter 5) expression. Using conditional endothelial-specific PFKFB3 knockout mice, we demonstrated that endothelial PFKFB3 knockout increases lung tissue lactate production after fructose gavage. Last, we showed that pneumonia increases fructose in BAL fluid in mechanically ventilated ICU patients. Thus, PFKFB3 knockout increases GLUT5 expression and the hexokinase-mediated fructose use in pulmonary microvascular endothelial cells that promotes their survival. Our findings indicate that PFKFB3 is a molecular switch that controls glucose versus fructose use in glycolysis and help better understand lung endothelial cell metabolism during respiratory failure.
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Affiliation(s)
- Ji Young Lee
- Department of Physiology and Cell Biology
- Division of Pulmonary and Critical Care Medicine
- Department of Internal Medicine
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Reece P. Stevens
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Viktoriya V. Pastukh
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Viktor M. Pastukh
- Department of Pharmacology, and
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Natalya Kozhukhar
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Mikhail F. Alexeyev
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | | | | | | | - Anna Koloteva
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Meredith S. Gwin
- Department of Physiology and Cell Biology
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Justin T. Roberts
- Department of Pharmacology, and
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Glen M. Borchert
- Department of Pharmacology, and
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
| | - Brant M. Wagener
- Division of Critical Care Medicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jean-François Pittet
- Division of Critical Care Medicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Brian B. Graham
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Lung Biology Center, University of California, San Francisco, San Francisco, California
| | - Kurt R. Stenmark
- Cardiovascular Pulmonary Research Laboratories, Department of Pediatrics and
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
| | - Troy Stevens
- Department of Physiology and Cell Biology
- Department of Internal Medicine
- Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, Alabama
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3
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Pokharel MD, Marciano DP, Fu P, Franco MC, Unwalla H, Tieu K, Fineman JR, Wang T, Black SM. Metabolic reprogramming, oxidative stress, and pulmonary hypertension. Redox Biol 2023; 64:102797. [PMID: 37392518 PMCID: PMC10363484 DOI: 10.1016/j.redox.2023.102797] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/15/2023] [Accepted: 06/23/2023] [Indexed: 07/03/2023] Open
Abstract
Mitochondria are highly dynamic organelles essential for cell metabolism, growth, and function. It is becoming increasingly clear that endothelial cell dysfunction significantly contributes to the pathogenesis and vascular remodeling of various lung diseases, including pulmonary arterial hypertension (PAH), and that mitochondria are at the center of this dysfunction. The more we uncover the role mitochondria play in pulmonary vascular disease, the more apparent it becomes that multiple pathways are involved. To achieve effective treatments, we must understand how these pathways are dysregulated to be able to intervene therapeutically. We know that nitric oxide signaling, glucose metabolism, fatty acid oxidation, and the TCA cycle are abnormal in PAH, along with alterations in the mitochondrial membrane potential, proliferation, and apoptosis. However, these pathways are incompletely characterized in PAH, especially in endothelial cells, highlighting the urgent need for further research. This review summarizes what is currently known about how mitochondrial metabolism facilitates a metabolic shift in endothelial cells that induces vascular remodeling during PAH.
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Affiliation(s)
- Marissa D Pokharel
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Cellular Biology & Pharmacology, Howard Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA
| | - David P Marciano
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Cellular Biology & Pharmacology, Howard Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA
| | - Panfeng Fu
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Environmental Health Sciences, Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL, 33199, USA
| | - Maria Clara Franco
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Cellular Biology & Pharmacology, Howard Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA
| | - Hoshang Unwalla
- Department of Immunology and Nano-Medicine, Howard Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA
| | - Kim Tieu
- Department of Environmental Health Sciences, Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL, 33199, USA
| | - Jeffrey R Fineman
- Department of Pediatrics, The University of California San Francisco, San Francisco, CA, 94143, USA; Cardiovascular Research Institute, The University of California San Francisco, San Francisco, CA, 94143, USA
| | - Ting Wang
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Environmental Health Sciences, Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL, 33199, USA
| | - Stephen M Black
- Center for Translational Science, Florida International University, 11350 SW Village Parkway, Port St. Lucie, FL, 34987-2352, USA; Department of Cellular Biology & Pharmacology, Howard Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA; Department of Environmental Health Sciences, Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL, 33199, USA.
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Mechanisms of pulmonary microvascular endothelial cells barrier dysfunction induced by LPS: The roles of ceramides and the Txnip/NLRP3 inflammasome. Microvasc Res 2023; 147:104491. [PMID: 36709858 DOI: 10.1016/j.mvr.2023.104491] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/12/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023]
Abstract
Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are characterized by pulmonary microvascular endothelial cells (PMVECs) barrier dysfunction and proinflammatory cytokine influx into lung tissue, resulting in pulmonary oedema. Ceramide overproduction is an important mediator of pulmonary hyperinflammation and pulmonary oedema in Acute lung injury (ALI). Ceramides induce NLRP3 inflammasome activation are essential for the hyperinflammatory response. However, the roles and specific mechanisms of ceramide-induced NLRP3 inflammasome activation, proinflammatory cytokine manufacturing and PMVECs barrier dysfunction in ALI are unclear. Herein, pretreatment with the acid sphingomyelinase (ASMase) inhibitor imipramine (but not a neutral sphingomyelinase (NSMase) inhibitor or de novo pathway inhibitor) significantly inhibited ceramide early production in rats with lipopolysaccharide (LPS)-induced ALI; Furthermore, the Txnip/NLRP3 inflammasome activation, proinflammatory cytokine release, increased PMVECs permeability and lung injury were significantly decreased. Verapamil, a Txnip inhibitor, substantially inhibited Txnip/NLRP3 inflammasome activation, proinflammatory cytokine release, increased PMVECs permeability and lung injury in rats with C8-ceramide-induced ALI. In vitro, short hairpin RNA-mediated Txnip silencing significantly inhibited C8-ceramide-induced Txnip/NLRP3 inflammasome activation in NR8383 alveolar macrophages (AMs) and early secretion of the proinflammatory cytokines IL-1β (4-12 h) as well as IL-6 and TNF-α at subsequent times (later than 12 h). However, C8-ceramide significantly increased the early secretion (within 8 h) of the proinflammatory cytokines IL-1β, IL-6 and TNF-α in a co-culture model of NR8383 AMs and PMVECs, and Txnip silencing of NR8383 AMs inhibited the secretion of pro-inflammatory cytokines and reduced cytoskeletal rearrangements, intercellular connection breakage and hyperpermeability in PMVECs. Overall, our results suggest that in LPS-induced ALI, ceramide-mediated Txnip/NLRP3 inflammasome activation in NR8383 AMs leads to early IL-1β release, subsequently inducing PMVECs injury and release of the proinflammatory cytokines IL-6 and TNF-α, ultimately leading to PMVECs barrier dysfunction and ALI.
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5
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Tepic S, Arens D, Buchholz T, Nehrbass D, Cvetkovic O, Stoddart MJ, Richards RG, Zeiter S. Arginine concentration in arterial vs venous blood in a bleomycin-induced lung inflammation model in mice. PLoS One 2023; 18:e0285770. [PMID: 37172030 PMCID: PMC10180604 DOI: 10.1371/journal.pone.0285770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 04/29/2023] [Indexed: 05/14/2023] Open
Abstract
Pneumonia, always a major malady, became the main public health and economic disaster of historical proportions with the COVID-19 pandemic. This study was based on a premise that pathology of lung metabolism in inflammation may have features invariant to the nature of the underlying cause. Amino acid uptake by the lungs was measured from plasma samples collected pre-terminally from a carotid artery and vena cava in mice with bleomycin-induced lung inflammation (N = 10) and compared to controls treated with saline instillation (N = 6). In the control group, the difference in concentrations between the arterial and venous blood of the 19 amino acids measured reached the level of statistical significance only for arginine (-10.7%, p = 0.0372) and phenylalanine (+5.5%, p = 0.0266). In the bleomycin group, 11 amino acids had significantly lower concentrations in the arterial blood. Arginine concentration was decreased by 21.1% (p<0.0001) and only that of citrulline was significantly increased (by 20.1%, p = 0.0002). Global Arginine Bioavailability Ratio was decreased in arterial blood by 19.5% (p = 0.0305) in the saline group and by 30.4% (p<0.0001) in the bleomycin group. Production of nitric oxide (NO) and citrulline from arginine by the inducible nitric oxide synthase (iNOS) is greatly increased in the immune system's response to lung injury. Deprived of arginine, the endothelial cells downstream may fail to provide enough NO to prevent the activation of thrombocytes. Thrombotic-related vascular dysfunction is a defining characteristic of pneumonia, including COVID-19. This experiment lends further support to arginine replacement as adjuvant therapy in pneumonia.
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6
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Ta HQ, Teman NR, Kron IL, Roeser ME, Laubach VE. Steen solution protects pulmonary microvascular endothelial cells and preserves endothelial barrier after lipopolysaccharide-induced injury. J Thorac Cardiovasc Surg 2023; 165:e5-e20. [PMID: 35577593 PMCID: PMC9576825 DOI: 10.1016/j.jtcvs.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Acute respiratory distress syndrome represents the devastating result of acute lung injury, with high mortality. Limited methods are available for rehabilitation of lungs affected by acute respiratory distress syndrome. Our laboratory has demonstrated rehabilitation of sepsis-injured lungs via normothermic ex vivo and in vivo perfusion with Steen solution (Steen). However, mechanisms responsible for the protective effects of Steen remain unclear. This study tests the hypothesis that Steen directly attenuates pulmonary endothelial barrier dysfunction and inflammation induced by lipopolysaccharide. METHODS Primary pulmonary microvascular endothelial cells were exposed to lipopolysaccharide for 4 hours and then recovered for 8 hours in complete media (Media), Steen, or Steen followed by complete media (Steen/Media). Oxidative stress, chemokines, permeability, interendothelial junction proteins, and toll-like receptor 4-mediated pathways were assessed in pulmonary microvascular endothelial cells using standard methods. RESULTS Lipopolysaccharide treatment of pulmonary microvascular endothelial cells and recovery in Media significantly induced reactive oxygen species, lipid peroxidation, expression of chemokines (eg, chemokine [C-X-C motif] ligand 1 and C-C motif chemokine ligand 2) and cell adhesion molecules (P-selectin, E-selectin, and vascular cell adhesion molecule 1), permeability, neutrophil transmigration, p38 mitogen-activated protein kinase and nuclear factor kappa B signaling, and decreased expression of tight and adherens junction proteins (zonula occludens-1, zonula occludens-2, and vascular endothelial-cadherin). All of these inflammatory pathways were significantly attenuated after recovery of pulmonary microvascular endothelial cells in Steen or Steen/Media. CONCLUSIONS Steen solution preserves pulmonary endothelial barrier function after lipopolysaccharide exposure by promoting an anti-inflammatory environment via attenuation of oxidative stress, toll-like receptor 4-mediated signaling, and conservation of interendothelial junctions. These protective mechanisms offer insight into the advancement of methods for in vivo lung perfusion with Steen for the treatment of severe acute respiratory distress syndrome.
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Affiliation(s)
| | | | | | | | - Victor E. Laubach
- Address for reprints: Victor E. Laubach, PhD, Department of Surgery, University of Virginia School of Medicine, PO Box 801359, Charlottesville, VA 22908
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7
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Li L, Cook C, Liu Y, Li J, Jiang J, Li S. Endothelial glycocalyx in hepatopulmonary syndrome: An indispensable player mediating vascular changes. Front Immunol 2022; 13:1039618. [PMID: 36618396 PMCID: PMC9815560 DOI: 10.3389/fimmu.2022.1039618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
Hepatopulmonary syndrome (HPS) is a serious pulmonary vascular complication that causes respiratory insufficiency in patients with chronic liver diseases. HPS is characterized by two central pathogenic features-intrapulmonary vascular dilatation (IPVD) and angiogenesis. Endothelial glycocalyx (eGCX) is a gel-like layer covering the luminal surface of blood vessels which is involved in a variety of physiological and pathophysiological processes including controlling vascular tone and angiogenesis. In terms of lung disorders, it has been well established that eGCX contributes to dysregulated vascular contraction and impaired blood-gas barrier and fluid clearance, and thus might underlie the pathogenesis of HPS. Additionally, pharmacological interventions targeting eGCX are dramatically on the rise. In this review, we aim to elucidate the potential role of eGCX in IPVD and angiogenesis and describe the possible degradation-reconstitution equilibrium of eGCX during HPS through a highlight of recent literature. These studies strongly underscore the therapeutic rationale in targeting eGCX for the treatment of HPS.
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Affiliation(s)
- Liang Li
- Department of Thoracic Surgery, the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China,*Correspondence: Liang Li, ; Shaomin Li,
| | - Christopher Cook
- Division of Immunology and Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, United States
| | - Yale Liu
- Department of Dermatology, the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Jianzhong Li
- Department of Thoracic Surgery, the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Jiantao Jiang
- Department of Thoracic Surgery, the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Shaomin Li
- Department of Thoracic Surgery, the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China,*Correspondence: Liang Li, ; Shaomin Li,
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8
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Lee MH, Menezes TCF, Reisz JA, Ferreira EVM, Graham BB, Oliveira RKF. Exercise metabolomics in pulmonary arterial hypertension: Where pulmonary vascular metabolism meets exercise physiology. Front Physiol 2022; 13:963881. [PMID: 36171971 PMCID: PMC9510894 DOI: 10.3389/fphys.2022.963881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/23/2022] [Indexed: 01/29/2023] Open
Abstract
Pulmonary arterial hypertension is an incurable disease marked by dysregulated metabolism, both at the cellular level in the pulmonary vasculature, and at the whole-body level characterized by impaired exercise oxygen consumption. Though both altered pulmonary vascular metabolism and abnormal exercise physiology are key markers of disease severity and pulmonary arterial remodeling, their precise interactions are relatively unknown. Herein we review normal pulmonary vascular physiology and the current understanding of pulmonary vascular cell metabolism and cardiopulmonary response to exercise in Pulmonary arterial hypertension. We additionally introduce a newly developed international collaborative effort aimed at quantifying exercise-induced changes in pulmonary vascular metabolism, which will inform about underlying pathophysiology and clinical management. We support our investigative approach by presenting preliminary data and discuss potential future applications of our research platform.
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Affiliation(s)
- Michael H. Lee
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
| | - Thaís C. F. Menezes
- Division of Respiratory Diseases, Department of Medicine, Federal University of SP, São Paulo, Brazil
| | - Julie A. Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Eloara V. M. Ferreira
- Division of Respiratory Diseases, Department of Medicine, Federal University of SP, São Paulo, Brazil
| | - Brian B. Graham
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
| | - Rudolf K. F. Oliveira
- Division of Respiratory Diseases, Department of Medicine, Federal University of SP, São Paulo, Brazil,*Correspondence: Rudolf K. F. Oliveira,
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9
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Stevens RP, Alexeyev MF, Kozhukhar N, Pastukh V, Paudel SS, Bell J, Tambe DT, Stevens T, Lee JY. Carbonic anhydrase IX proteoglycan-like and intracellular domains mediate pulmonary microvascular endothelial cell repair and angiogenesis. Am J Physiol Lung Cell Mol Physiol 2022; 323:L48-L57. [PMID: 35672011 DOI: 10.1152/ajplung.00337.2021] [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
The lungs of patients with acute respiratory distress syndrome (ARDS) have hyperpermeable capillaries that must undergo repair in an acidic microenvironment. Pulmonary microvascular endothelial cells (PMVECs) have an acid-resistant phenotype, in part due to carbonic anhydrase IX (CA IX). CA IX also facilitates PMVEC repair by promoting aerobic glycolysis, migration, and network formation. Molecular mechanisms of how CA IX performs such a wide range of functions are unknown. CA IX is comprised of four domains known as the proteoglycan-like (PG), catalytic (CA), transmembrane (TM), and intracellular (IC) domains. We hypothesized that the PG and CA domains mediate PMVEC pH homeostasis and repair, and the IC domain regulates aerobic glycolysis and PI3k/Akt signaling. The functions of each CA IX domain were investigated using PMVEC cell lines that express either a full-length CA IX protein or a CA IX protein harboring a domain deletion. We found that the PG domain promotes intracellular pH homeostasis, migration, and network formation. The CA and IC domains mediate Akt activation but negatively regulate aerobic glycolysis. The IC domain also supports migration while inhibiting network formation. Finally, we show that exposure to acidosis suppresses aerobic glycolysis and migration, even though intracellular pH is maintained in PMVECs. Thus, we report that 1) The PG and IC domains mediate PMVEC migration and network formation, 2) the CA and IC domains support PI3K/Akt signaling, and 3) acidosis impairs PMVEC metabolism and migration independent of intracellular pH homeostasis.
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Affiliation(s)
- Reece P Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Mikhail F Alexeyev
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Natalya Kozhukhar
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Viktoriya Pastukh
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Sunita S Paudel
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Jessica Bell
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Dhananjay T Tambe
- Department of Mechanical, Aerospace, and Biomedical Engineering, College of Medicine, University of South Alabama, Mobile, Alabama, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Troy Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
| | - Ji Young Lee
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL, United States.,Department of Internal Medicine, College of Medicine, University of South Alabama, Mobile, Alabama, United States.,Division of Pulmonary and Critical Care Medicine, College of Medicine, University of South Alabama, Mobile, AL, United States.,Center for Lung Biology, College of Medicine, University of South Alabama, Mobile, AL, United States
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10
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Adams D, Choi CS, Sayner SL. Pulmonary endothelial cells from different vascular segments exhibit unique recovery from acidification and Na+/H+ exchanger isoform expression. PLoS One 2022; 17:e0266890. [PMID: 35503765 PMCID: PMC9064095 DOI: 10.1371/journal.pone.0266890] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 03/29/2022] [Indexed: 12/29/2022] Open
Abstract
Sodium-hydrogen exchangers (NHEs) tightly regulate intracellular pH (pHi), proliferation, migration and cell volume. Heterogeneity exists between pulmonary endothelial cells derived from different vascular segments, yet the activity and isoform expression of NHEs between these vascular segments has not been fully examined. Utilizing the ammonium-prepulse and recovery from acidification technique in a buffer lacking bicarbonate, pulmonary microvascular and pulmonary artery endothelial cells exhibited unique recovery rates from the acid load dependent upon the concentration of the sodium transport inhibitor, amiloride; further, pulmonary artery endothelial cells required a higher dose of amiloride to inhibit sodium-dependent acid recovery compared to pulmonary microvascular endothelial cells, suggesting a unique complement of NHEs between the different endothelial cell types. While NHE1 has been described in pulmonary endothelial cells, all NHE isoforms have not been accounted for. To address NHE expression in endothelial cells, qPCR was performed. Using a two-gene normalization approach, Sdha and Ywhag were identified for qPCR normalization and analysis of NHE isoforms between pulmonary microvascular and pulmonary artery endothelial cells. NHE1 and NHE8 mRNA were equally expressed between the two cell types, but NHE5 expression was significantly higher in pulmonary microvascular versus pulmonary artery endothelial cells, which was confirmed at the protein level. Thus, pulmonary microvascular and pulmonary artery endothelial cells exhibit unique NHE isoform expression and have a unique response to acid load revealed through recovery from cellular acidification.
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Affiliation(s)
- Dylan Adams
- Department of Physiology and Cell Biology, University South Alabama, College of Medicine, Mobile, Alabama, United States of America
| | - Chung-Sik Choi
- Department of Physiology and Cell Biology, University South Alabama, College of Medicine, Mobile, Alabama, United States of America
| | - Sarah L. Sayner
- Department of Physiology and Cell Biology, University South Alabama, College of Medicine, Mobile, Alabama, United States of America
- Center for Lung Biology, University of South Alabama, College of Medicine, Mobile, Alabama, United States of America
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