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Ray EC, Nickerson A, Sheng S, Carrisoza-Gaytan R, Lam T, Marciszyn A, Zhang L, Jordahl A, Bi C, Winfrey A, Kou Z, Gingras S, Kirabo A, Satlin LM, Kleyman TR. Influence of proteolytic cleavage of ENaC's γ subunit upon Na + and K + handling. Am J Physiol Renal Physiol 2024; 326:F1066-F1077. [PMID: 38634134 DOI: 10.1152/ajprenal.00027.2024] [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: 01/23/2024] [Revised: 03/27/2024] [Accepted: 04/09/2024] [Indexed: 04/19/2024] Open
Abstract
The epithelial Na+ channel (ENaC) γ subunit is essential for homeostasis of Na+, K+, and body fluid. Dual γ subunit cleavage before and after a short inhibitory tract allows dissociation of this tract, increasing channel open probability (PO), in vitro. Cleavage proximal to the tract occurs at a furin recognition sequence (143RKRR146, in the mouse γ subunit). Loss of furin-mediated cleavage prevents in vitro activation of the channel by proteolysis at distal sites. We hypothesized that 143RKRR146 mutation to 143QQQQ146 (γQ4) in 129/Sv mice would reduce ENaC PO, impair flow-stimulated flux of Na+ (JNa) and K+ (JK) in perfused collecting ducts, reduce colonic amiloride-sensitive short-circuit current (ISC), and impair Na+, K+, and body fluid homeostasis. Immunoblot of γQ4/Q4 mouse kidney lysates confirmed loss of a band consistent in size with the furin-cleaved proteolytic fragment. However, γQ4/Q4 male mice on a low Na+ diet did not exhibit altered ENaC PO or flow-induced JNa, though flow-induced JK modestly decreased. Colonic amiloride-sensitive ISC in γQ4/Q4 mice was not altered. γQ4/Q4 males, but not females, exhibited mildly impaired fluid volume conservation when challenged with a low Na+ diet. Blood Na+ and K+ were unchanged on a regular, low Na+, or high K+ diet. These findings suggest that biochemical evidence of γ subunit cleavage should not be used in isolation to evaluate ENaC activity. Furthermore, factors independent of γ subunit cleavage modulate channel PO and the influence of ENaC on Na+, K+, and fluid volume homeostasis in 129/Sv mice, in vivo.NEW & NOTEWORTHY The epithelial Na+ channel (ENaC) is activated in vitro by post-translational proteolysis. In vivo, low Na+ or high K+ diets enhance ENaC proteolysis, and proteolysis is hypothesized to contribute to channel activation in these settings. Using a mouse expressing ENaC with disruption of a key proteolytic cleavage site, this study demonstrates that impaired proteolytic activation of ENaC's γ subunit has little impact upon channel open probability or the ability of mice to adapt to low Na+ or high K+ diets.
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Affiliation(s)
- Evan C Ray
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Andrew Nickerson
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Shaohu Sheng
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Rolando Carrisoza-Gaytan
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York City, New York, United States
| | - Tracey Lam
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Allison Marciszyn
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Lei Zhang
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Alexa Jordahl
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Chunming Bi
- Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Aaliyah Winfrey
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Zhaohui Kou
- Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Sebastien Gingras
- Department of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Annet Kirabo
- Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, United States
| | - Lisa M Satlin
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York City, New York, United States
| | - Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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Laurenzi G, Fedeli V, Canipari R. Decreased fertility in female mice lacking urokinase plasminogen activator. Reprod Biol 2024; 24:100840. [PMID: 38113659 DOI: 10.1016/j.repbio.2023.100840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 11/24/2023] [Accepted: 11/26/2023] [Indexed: 12/21/2023]
Abstract
It is well established that mouse ovarian granulosa cells secrete urokinase plasminogen activator (uPA) under gonadotropin stimulation. The synthesis and secretion of the enzyme correlate well with the time of follicular rupture in vivo. Moreover, uPA is secreted by the trophoblast at the time of implantation. In the present study, we have analyzed whether the absence of uPA could influence follicular growth, ovulation, and embryo implantation. Our data show fewer preantral follicles in uPA-/- ovaries but no decrease in hormonally induced ovulation. However, we observed a significant decrease in the number of implanted embryos in uPA-/- animals and, therefore, a lower number of pups per family. Adding uPA to the epithelial and stromal uterine cell culture medium strongly upregulates the expression of prostaglandin-endoperoxide synthase 2 (Ptgs2), the enzyme required for prostaglandin production and embryo implantation. The uPA inhibitor amiloride abrogated this increase.
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Affiliation(s)
- Gaia Laurenzi
- Department of Anatomy, Histology, Forensic Medicine and Orthopedic, Section of Histology, Sapienza University of Rome, Rome, Italy
| | - Valeria Fedeli
- Department of Anatomy, Histology, Forensic Medicine and Orthopedic, Section of Histology, Sapienza University of Rome, Rome, Italy
| | - Rita Canipari
- Department of Anatomy, Histology, Forensic Medicine and Orthopedic, Section of Histology, Sapienza University of Rome, Rome, Italy.
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Ray EC, Nickerson A, Sheng S, Carrisoza-Gaytan R, Lam T, Marciszyn A, Zhang L, Jordahl A, Bi C, Winfrey A, Kou Z, Gingras S, Kirabo A, Satlin LM, Kleyman TR. Proteolytic Cleavage of the ENaC γ Subunit - Impact Upon Na + and K + Handling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.12.579964. [PMID: 38405735 PMCID: PMC10888851 DOI: 10.1101/2024.02.12.579964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
The ENaC gamma subunit is essential for homeostasis of Na + , K + , and body fluid. Dual subunit cleavage before and after a short inhibitory tract allows dissociation of this tract, increasing channel open probability (P O ), in vitro . Cleavage proximal to the tract occurs at a furin recognition sequence ( 143 RKRR 146 in mouse). Loss of furin-mediated cleavage prevents in vitro activation of the channel by proteolysis at distal sites. We hypothesized that 143 RKRR 146 mutation to 143 QQQQ 146 ( Q4 ) in 129/Sv mice would reduce ENaC P O , impair flow-stimulated flux of Na + (J Na ) and K + (J K ) in perfused collecting ducts, reduce colonic amiloride-sensitive short circuit current (I SC ), and impair Na + , K + , and body fluid homeostasis. Immunoblot of Q4/Q4 mouse kidney lysates confirmed loss of a band consistent in size with the furin-cleaved proteolytic fragment. However, Q4/Q4 male mice on a low Na + diet did not exhibit altered ENaC P O or flow-induced J Na , though flow-induced J K modestly decreased. Colonic amiloride-sensitive I SC in Q4/Q4 mice was not altered. Q4/Q4 males, but not females, exhibited mildly impaired fluid volume conservation when challenged with a low Na + diet. Blood Na + and K + were unchanged on a regular, low Na + , or high K + diet. These findings suggest that biochemical evidence of gamma subunit cleavage should not be used in isolation to evaluate ENaC activity. Further, factors independent of gamma subunit cleavage modulate channel P O and the influence of ENaC on Na + , K + , and fluid volume homeostasis in 129/Sv mice, in vivo .
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Ali G, Zhang M, Chang J, Zhao R, Jin Y, Zhang J, Ji HL. PAI-1 regulates AT2-mediated re-alveolarization and ion permeability. Stem Cell Res Ther 2023; 14:185. [PMID: 37501095 PMCID: PMC10375781 DOI: 10.1186/s13287-023-03414-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 07/14/2023] [Indexed: 07/29/2023] Open
Abstract
BACKGROUND Acute lung injury is characterized by overwhelmingly elevated PAI-1 in both lung edema fluid and the circulating system. The role of increased PAI-1, encoded by Serpine1 gene, in the regeneration of injured lung epithelium has not been understood completely. This study aimed to investigate the role of Serpine1 in the regulation of alveolar type 2 epithelial cell (AT2) fate in a humanized mouse line carrying diseased mutants (Serpine1Tg). METHODS Wild-type (wt) and Serpine1Tg AT2 cells were either cultured as monolayers or 3D alveolospheres. Colony-forming assay and total surface area of organoids were analyzed. AT1 and AT2 cells in organoids were counted by immunohistochemistry and fluorescence-activated cell sorting (FACS). To test the potential effects of elevated PAI-1 on the permeability in the epithelial monolayers, we digitized the biophysical properties of polarized AT2 monolayers grown at the air-liquid interface. RESULTS A significant reduction in total AT2 cells harvested in Serpine1Tg mice was observed compared with wt controls. AT2 cells harvested from Serpine1Tg mice reduced significantly over the wt controls. Spheroids formed by Serpine1Tg AT2 cells were lesser than wt control. Similarly, the corresponding surface area, a readout of re-alveolarization of injured epithelium, was markedly reduced in Serpine1Tg organoids. FACS analysis revealed a significant suppression in the number of AT2 cells, in particular, the CD44+ subpopulation, in Serpine1Tg organoids. A lesser ratio of AT1:AT2 cells in Serpine1Tg organoids was observed compared with wt cultures. There was a significant increase in transepithelial resistance but not amiloride inhibition. CONCLUSIONS Our study suggests elevated PAI-1 in injured lungs downregulates alveolar epithelial regeneration by reducing the AT2 self-renewal, particularly in the CD44+ cells.
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Affiliation(s)
- Gibran Ali
- Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA
| | - Mo Zhang
- Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA
- Xinxiang Medical University, Xinxiang, Henan, China
| | - Jianjun Chang
- Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA
- Department of Surgery, Burn and Shock Trauma Research Institute, Loyola University Chicago, 2160 S 1St Avenue, Maywood, IL, 60153, USA
| | - Yang Jin
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Boston University, Boston, MA, USA
| | - Jiwang Zhang
- Department of Cancer Biology, Oncology Institute, Cardinal Bernardin Cancer Center, Loyola University Medical Center, Maywood, IL, USA
| | - Hong-Long Ji
- Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA.
- Department of Surgery, Burn and Shock Trauma Research Institute, Loyola University Chicago, 2160 S 1St Avenue, Maywood, IL, 60153, USA.
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Fu Y, Xue H, Wang T, Ding Y, Cui Y, Nie H. Fibrinolytic system and COVID-19: From an innovative view of epithelial ion transport. Biomed Pharmacother 2023; 163:114863. [PMID: 37172333 PMCID: PMC10169260 DOI: 10.1016/j.biopha.2023.114863] [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: 03/13/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/14/2023] Open
Abstract
Lifeways of worldwide people have changed dramatically amid the coronavirus disease 2019 (COVID-19) pandemic, and public health is at stake currently. In the early stage of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, fibrinolytic system is mostly inhibited, which is responsible for the development of hypofibrinolysis, promoting disseminated intravascular coagulation, hyaline membrane formation, and pulmonary edema. Whereas the common feature and risk factor at advanced stage is a large amount of fibrin degradation products, including D-dimer, the characteristic of hyperfibrinolysis. Plasmin can cleave both SARS-CoV-2 spike protein and γ subunit of epithelial sodium channel (ENaC), a critical element to edematous fluid clearance. In this review, we aim to sort out the role of fibrinolytic system in the pathogenesis of COVID-19, as well as provide the possible guidance in current treating methods. In addition, the abnormal regulation of ENaC in the occurrence of SARS-CoV-2 mediated hypofibrinolysis and hyperfibrinolysis are summarized, with the view of proposing an innovative view of epithelial ion transport in preventing the dysfunction of fibrinolytic system during the progress of COVID-19.
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Affiliation(s)
- Yunmei Fu
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Hao Xue
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Tingyu Wang
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Yan Ding
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang 110122, China
| | - Yong Cui
- Department of Anesthesiology, the First Hospital of China Medical University, Shenyang 110001, China.
| | - Hongguang Nie
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang 110122, China.
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Ali G, Zhang M, Chang J, Zhao R, Jin Y, Ji HL. PAI-1 regulates AT2-mediated re-alveolarization and ion permeability. RESEARCH SQUARE 2023:rs.3.rs-2289657. [PMID: 36909505 PMCID: PMC10002791 DOI: 10.21203/rs.3.rs-2289657/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Background Acute lung injury is characterized by overwhelmingly elevated PAI-1 in both lung edema fluid and the circulating system. The role of increased PAI-1, encoded by Serpine1 gene, in the regeneration of injured lung epithelium has not been understood completely. This study aimed to investigate the role of Serpine1 in the regulation of alveolar type 2 epithelial cell (AT2) fate in a humanized mouse line carrying diseased mutants (Serpine1Tg). Methods Wild type (wt) and Serpine1Tg AT2 cells were either cultured as monolayers or 3D alveolospheres. Colony forming assay and total surface area of organoids were analyzed. AT1 and AT2 cells in organoids were counted by immunohistochemistry and fluorescence-activated cell sorting (FACS). To test the potential effects of elevated PAI-1 on the permeability in the epithelial monolayers, we digitized the biophysical properties of polarized AT2 monolayers grown at the air-liquid interface. Results A significant reduction in total AT2 cells harvested in Serpine1Tg mice was observed compared with wt controls. AT2 cells harvested from Serpine1Tg mice reduced significantly over the wt controls. Spheroids formed by Serpine1Tg AT2 cells were lesser than wt control. Similarly, the corresponding surface area, a readout of realveolarization of injured epithelium, was markedly reduced in Serpine1Tg organoids. FACS analysis revealed a significant suppression in the number of AT2 cells, in particular, the CD44+ subpopulation, in Serpine1Tg organoids. A lesser ratio of AT1:AT2 cells in Serpine1Tg organoids was observed compared with wt cultures. There was a significant increase in transepithelial resistance but not amiloride inhibition. Conclusions Our study suggests elevated PAI-1 in injured lungs downregulates alveolar epithelial regeneration by reducing the AT2 self-renewal, particularly in the CD44+ cells.
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Affiliation(s)
- Gibran Ali
- Department of Cellular and Molecular Biology, University of Texas at Tyler Health Science Center, Tyler, TX, USA
| | - Mo Zhang
- Department of Cellular and Molecular Biology, University of Texas at Tyler Health Science Center, Tyler, TX, USA
- Xinxiang Medical University, Xinxiang, Henan, China
| | - Jianjun Chang
- Department of Cellular and Molecular Biology, University of Texas at Tyler Health Science Center, Tyler, TX, USA
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas at Tyler Health Science Center, Tyler, TX, USA
| | - Yang Jin
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Boston University, Boston, MA, USA
| | - Hong-Long Ji
- Department of Cellular and Molecular Biology, University of Texas at Tyler Health Science Center, Tyler, TX, USA
- Texas Lung Injury Institute, University of Texas at Tyler Health Science Center, Tyler, TX, USA
- Corresponding Author: Dr. Hong-Long (James) Ji, M.D., Ph.D., , University of Texas at Tyler Health Science Center, 11937 US Highway 271, Tyler, TX 75708-3154, USA
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Anand D, Hummler E, Rickman OJ. ENaC activation by proteases. Acta Physiol (Oxf) 2022; 235:e13811. [PMID: 35276025 PMCID: PMC9540061 DOI: 10.1111/apha.13811] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/04/2022] [Accepted: 03/08/2022] [Indexed: 12/13/2022]
Abstract
Proteases are fundamental for a plethora of biological processes, including signalling and tissue remodelling, and dysregulated proteolytic activity can result in pathogenesis. In this review, we focus on a subclass of membrane‐bound and soluble proteases that are defined as channel‐activating proteases (CAPs), since they induce Na+ ion transport through an autocrine mechanism when co‐expressed with the highly amiloride‐sensitive epithelial sodium channel (ENaC) in Xenopus oocytes. These experiments first identified CAP1 (channel‐activating protease 1, prostasin) followed by CAP2 (channel‐activating protease 2, TMPRSS4) and CAP3 (channel‐activating protease 3, matriptase) as in vitro mediators of ENaC current. Since then, more serine‐, cysteine‐ and metalloproteases were confirmed as in vitro CAPs that potentially cleave and regulate ENaC, and thus this nomenclature was not further followed, but is accepted as functional term or alias. The precise mechanism of ENaC modulation by proteases has not been fully elucidated. Studies in organ‐specific protease knockout models revealed evidence for their role in increasing ENaC activity, although the proteases responsible for ENaC activation are yet to be identified. We summarize recent findings in animal models of these CAPs with respect to their implication in ENaC activation. We discuss the consequences of dysregulated CAPs underlying epithelial phenotypes in pathophysiological conditions, and the role of selected protease inhibitors. We believe that these proteases may present interesting therapeutic targets for diseases with aberrant sodium homoeostasis.
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Affiliation(s)
- Deepika Anand
- Department of Biomedical Sciences University of Lausanne Lausanne Switzerland
- National Center of Competence in Research, Kidney.CH Lausanne Switzerland
| | - Edith Hummler
- Department of Biomedical Sciences University of Lausanne Lausanne Switzerland
- National Center of Competence in Research, Kidney.CH Lausanne Switzerland
| | - Olivia J. Rickman
- Department of Biomedical Sciences University of Lausanne Lausanne Switzerland
- National Center of Competence in Research, Kidney.CH Lausanne Switzerland
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Ji HL, Wagener BM, Ness TJ, Zhao R. Fibrinolytic or anti-plasmin (nafamostat) therapy for COVID-19: A timing challenge for clinicians. Pulm Pharmacol Ther 2021; 70:102055. [PMID: 34271164 PMCID: PMC8276553 DOI: 10.1016/j.pupt.2021.102055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/08/2021] [Accepted: 07/11/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Hong-Long Ji
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, TX 75708, USA; Texas Lung Injury Institute, The University of Texas Health Science Centre at Tyler, Tyler, TX 75708, USA.
| | - Brant M Wagener
- Division of Molecular and Translational Biomedicine, USA; Division of Critical Care Medicine, Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Timothy J Ness
- Division of Molecular and Translational Biomedicine, USA.
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, TX 75708, USA.
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Zhang J, Yuan HK, Chen S, Zhang ZR. Detrimental or beneficial: Role of endothelial ENaC in vascular function. J Cell Physiol 2021; 237:29-48. [PMID: 34279047 DOI: 10.1002/jcp.30505] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 12/19/2022]
Abstract
In the past, it was believed that the expression of the epithelial sodium channel (ENaC) was restricted to epithelial tissues, such as the distal nephron, airway, sweat glands, and colon, where it is critical for sodium homeostasis. Over the past two decades, this paradigm has shifted due to the finding that ENaC is also expressed in various nonepithelial tissues, notably in vascular endothelial cells. In this review, the recent findings of the expression, regulation, and function of the endothelial ENaC (EnNaC) are discussed. The expression of EnNaC subunits is reported in a variety of endothelial cell lines and vasculatures, but this is controversial across different species and vessels and is not a universal finding in all vascular beds. The expression density of EnNaC is very faint compared to ENaC in the epithelium. To date, little is known about the regulatory mechanism of EnNaC. Through it can be regulated by aldosterone, the detailed downstream signaling remains elusive. EnNaC responds to increased extracellular sodium with the feedforward activation mechanism, which is quite different from the Na+ self-inhibition mechanism of ENaC. Functionally, EnNaC was shown to be a determinant of cellular mechanics and vascular tone as it can sense shear stress, and its activation or insertion into plasma membrane causes endothelial stiffness and reduced nitric oxide production. However, in some blood vessels, EnNaC is essential for maintaining the integrity of endothelial barrier function. In this context, we discuss the possible reasons for the distinct role of EnNaC in vasculatures.
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Affiliation(s)
- Jun Zhang
- School of Biomedical Sciences and Li Ka Shing Institute of Health Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Hui-Kai Yuan
- Department of General Surgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Shuo Chen
- Department of Biopharmaceutical Sciences, School of Pharmacy, Harbin Medical University (Daqing), Daqing, China
| | - Zhi-Ren Zhang
- Departments of Pharmacy and Cardiology, Harbin Medical University Cancer Hospital, Institute of Metabolic Disease, Heilongjiang Academy of Medical Science, Heilongjiang Key Laboratory for Metabolic Disorder & Cancer Related Cardiovascular Diseases, NHC Key Laboratory of Cell Transplantation, Harbin Medical University & Key Laboratories of Education Ministry for Myocardial Ischemia Mechanism and Treatment, Harbin, China
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Zhou Z, Hua Y, Ding Y, Hou Y, Yu T, Cui Y, Nie H. Conditioned Medium of Bone Marrow Mesenchymal Stem Cells Involved in Acute Lung Injury by Regulating Epithelial Sodium Channels via miR-34c. Front Bioeng Biotechnol 2021; 9:640116. [PMID: 34368091 PMCID: PMC8336867 DOI: 10.3389/fbioe.2021.640116] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Accepted: 05/17/2021] [Indexed: 01/01/2023] Open
Abstract
Background One of the characteristics of acute lung injury (ALI) is severe pulmonary edema, which is closely related to alveolar fluid clearance (AFC). Mesenchymal stem cells (MSCs) secrete a wide range of cytokines, growth factors, and microRNA (miRNAs) through paracrine action to participate in the mechanism of pulmonary inflammatory response, which increase the clearance of edema fluid and promote the repair process of ALI. The epithelial sodium channel (ENaC) is the rate-limiting step in the sodium–water transport and edema clearance in the alveolar cavity; the role of bone marrow-derived MSC-conditioned medium (BMSC-CM) in edema clearance and how miRNAs affect ENaC are still seldom known. Methods CCK-8 cell proliferation assay was used to detect the effect of BMSC-CM on the survival of alveolar type 2 epithelial (AT2) cells. Real-time polymerase chain reaction (RT-PCR) and western blot were used to detect the expression of ENaC in AT2 cells. The effects of miR-34c on lung fluid absorption were observed in LPS-treated mice in vivo, and the transepithelial short-circuit currents in the monolayer of H441 cells were examined by the Ussing chamber setup. Dual luciferase reporter gene assay was used to detect the target gene of miR-34c. Results BMSC-CM could increase the viability of mouse AT2 cells. RT-PCR and western blot results showed that BMSC-CM significantly increased the expression of the γ-ENaC subunit in mouse AT2 cells. MiR-34c could restore the AFC and lung wet/dry weight ratio in the ALI animal model, and Ussing chamber assay revealed that miR-34c enhanced the amiloride-sensitive currents associated with ENaC activity in intact H441 cell monolayers. In addition, we observed a higher expression of miR-34c in mouse AT2 cells administrated with BMSC-CM, and the overexpression or inhibition of miR-34c could regulate the expression of ENaC protein and alter the function of ENaC. Finally, we detected that myristoylated alanine-rich C kinase substrate (MARCKS) may be one of the target genes of miR-34c. Conclusion Our results indicate that BMSC-CM may alleviate LPS-induced ALI through miR-34c targeting MARCKS and regulate ENaC indirectly, which further explores the benefit of paracrine effects of bone marrow-derived MSCs on edematous ALI.
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Affiliation(s)
- Zhiyu Zhou
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yu Hua
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yan Ding
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yapeng Hou
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Tong Yu
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yong Cui
- Department of Anesthesiology, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Hongguang Nie
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
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11
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Kaur U, Chakrabarti SS, Ojha B, Pathak BK, Singh A, Saso L, Chakrabarti S. Targeting Host Cell Proteases to Prevent SARS-CoV-2 Invasion. Curr Drug Targets 2021; 22:192-201. [PMID: 32972339 DOI: 10.2174/1389450121666200924113243] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/16/2020] [Accepted: 08/26/2020] [Indexed: 11/22/2022]
Abstract
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has spread worldwide and caused widespread devastation. In the absence of definitive therapy, symptomatic management remains the standard of care. Repurposing of many existing drugs, including several anti-viral drugs, is being attempted to tackle the COVID-19 pandemic. However, most of them have failed to show significant benefit in clinical trials. An attractive approach may be to target host proteases involved in SARS-CoV-2 pathogenesis. The priming of the spike (S) protein of the virus by proteolytic cleavage by the transmembrane serine protease-2 (TMPRSS2) is necessary for the fusion of the virus to the host cell after it binds to its receptor angiotensin converting enzyme-2 (ACE2). There are other proteases with varying spatiotemporal locations that may be important for viral entry and subsequent replication inside the cells, and these include trypsin, furin and cathepsins. In this report, we have discussed the tentative therapeutic role of inhibitors of TMPRSS2, cathepsin, trypsin, furin, plasmin, factor X and elastase in infection caused by SARS-CoV-2. Both available evidence, as well as hypotheses, are discussed, with emphasis on drugs which are approved for other indications such as bromhexine, ammonium chloride, nafamostat, camostat, tranexamic acid, epsilon amino-caproic acid, chloroquine, ulinastatin, aprotinin and anticoagulant drugs. Simultaneously, novel compounds being tested and problems with using these agents are also discussed.
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Affiliation(s)
- Upinder Kaur
- Department of Pharmacology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, UP, India
| | - Sankha Shubhra Chakrabarti
- Department of Geriatric Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, UP, India
| | - Bisweswar Ojha
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, India
| | - Bhairav Kumar Pathak
- Department of Biochemistry and Central Research Cell, MM Institute of Medical Sciences and Research, Maharishi Markandeshwar (deemed to be) University, Mullana, Ambala, Haryana, India
| | - Amit Singh
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, India
| | - Luciano Saso
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Sasanka Chakrabarti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, India
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12
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Fibrinolytic niche is required for alveolar type 2 cell-mediated alveologenesis via a uPA-A6-CD44 +-ENaC signal cascade. Signal Transduct Target Ther 2021; 6:97. [PMID: 33640905 PMCID: PMC7910758 DOI: 10.1038/s41392-021-00511-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/15/2021] [Accepted: 01/27/2021] [Indexed: 11/09/2022] Open
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13
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Urinary proteomics reveals key markers of salt sensitivity in hypertensive patients during saline infusion. J Nephrol 2021; 34:739-751. [PMID: 33398797 DOI: 10.1007/s40620-020-00877-z] [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] [Received: 06/16/2020] [Accepted: 09/23/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Hypertension is a complex disease and is the major cause of cardiovascular complications. In the vast majority of individuals, the aetiology of elevated blood pressure (BP) cannot be determined, thus impairing optimized therapies and prognosis for individual patients. A more precise understanding of the molecular pathogenesis of hypertension remains a pressing priority for both basic and translational research. Here we investigated the effect of salt on naive hypertensive patients in order to better understand the salt intake-blood pressure relationship. METHODS Patients underwent an acute saline infusion and were defined as salt-sensitive or salt-resistant according to mean blood pressure changes. Urinary proteome changes during the salt load test were analysed by a label-free quantitative proteomics approach. RESULTS Our data show that salt-sensitive patients display equal sodium reabsorption as salt-resistant patients, as major sodium transporters show the same behaviour during the salt load. However, salt-sensitive patients regulate the renin angiotensin system (RAS) differently from salt-resistant patients, and upregulate proteins, as epidermal growth factor (EGF) and plasminogen activator, urokinase (PLAU), involved in the regulation of epithelial sodium channel ENaC activity. CONCLUSIONS Salt-sensitive and salt-resistant subjects have similar response to a saline/volume infusion as detected by urinary proteome. However, we identified glutamyl aminopeptidase (ENPEP), PLAU, EGF and Xaa-Pro aminopeptidase 2 precursor XPNPEP2 as key molecules of salt-sensitivity, through modulation of ENaC-dependent sodium reabsorption along the distal tubule.
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14
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Abstract
PURPOSE OF REVIEW The main goal of this article is to discuss the role of the epithelial sodium channel (ENaC) in extracellular fluid and blood pressure regulation. RECENT FINDINGS Besides its role in sodium handling in the kidney, recent studies have found that ENaC expressed in other cells including immune cells can influence blood pressure via extra-renal mechanisms. Dendritic cells (DCs) are activated and contribute to salt-sensitive hypertension in an ENaC-dependent manner. We discuss recent studies on how ENaC is regulated in both the kidney and other sites including the vascular smooth muscles, endothelial cells, and immune cells. We also discuss how this extra-renal ENaC can play a role in salt-sensitive hypertension and its promise as a novel therapeutic target. The role of ENaC in blood pressure regulation in the kidney has been well studied. Recent human gene sequencing efforts have identified thousands of variants among the genes encoding ENaC, and research efforts to determine if these variants and their expression in extra-renal tissue play a role in hypertension will advance our understanding of the pathogenesis of ENaC-mediated cardiovascular disease and lead to novel therapeutic targets.
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Affiliation(s)
- Ashley L Pitzer
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA
| | - Justin P Van Beusecum
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA
| | - Thomas R Kleyman
- Departments of Medicine, Cell Biology, Pharmacology, and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Annet Kirabo
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, 2215 Garland Avenue, P415C Medical Research Building IV, Nashville, TN, 37232, USA. .,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA.
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15
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Kenarkoohi A, Maleki M, Safari T, Kafashian M, Saljoughi F, Sohrabipour S. Angiotensin-converting Enzyme 2 roles in the Pathogenesis of COVID-19. Curr Hypertens Rev 2020; 17:207-216. [PMID: 32778033 DOI: 10.2174/1573402116666200810134702] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/13/2020] [Accepted: 07/17/2020] [Indexed: 11/22/2022]
Abstract
The new pandemic Coronavirus Disease 2019 (COVID-19) causes a wide range of clinical consequences, from asymptomatic infection to acute respiratory failure and it is very heterogeneous. The renin-angiotensin system (RAS) is well recognized as a key regulating system in circulatory homeostasis that play prominent roles in pathophysiological processes in abnormal activation for instance renal and cardiovascular diseases, obesity, and stroke. Angiotensin converting enzyme 2(ACE2) as a component of the RAS system. However, unlike the ACE, its activity is not inhibited by the ACE inhibitors. The major product of ACE2 is Ang1-7, known as a vasodilator peptide and part of the depressant arm of the RAS. There are two form of ACE2. Coronavirus cover with some proteins in order to help viral attachment to the cell membrane ACE2 as a receptor and then fuse and enter the cells. ACE2 was expressed in oral Cavity, salivary glands of the mouth, esophagus, myocardial cells, kidney, and enterocytes, along all the respiratory tract, intestine, and blood vessels. In this article, we explain the renin-angiotensin system and its components. Also, we shortly explain the organs involved in COVID-19 disease and we will talk about the possible causes of damage to these organs. We also reviewed the probable mechanism of using ACE2 in viral attachment and the probable treatment processes will also be discussed based on the surface proteins of the virus and ACE2. In addition, we briefly discuss the anti-angiotensin drugs and why patients with chronic disease are more susceptible to COVID-19 infection and show worse progression.
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Affiliation(s)
- Azra Kenarkoohi
- Department of Microbiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam. Iran
| | - Maryam Maleki
- Department of Physiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam. Iran
| | - Tahereh Safari
- Department of Physiology, Faculty of Medicine, Zahedan University of Medical Sciences, Zahedan. Iran
| | - Mohamadreza Kafashian
- Department of Physiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam. Iran
| | - Fateme Saljoughi
- Student Research Committee, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas. Iran
| | - Shahla Sohrabipour
- Endocrinology and Metabolism Research Center, Hormozgan University of Medical Sciences, Bandar Abbas. Iran
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16
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Ji HL, Zhao R, Matalon S, Matthay MA. Elevated Plasmin(ogen) as a Common Risk Factor for COVID-19 Susceptibility. Physiol Rev 2020; 100:1065-1075. [PMID: 32216698 PMCID: PMC7191627 DOI: 10.1152/physrev.00013.2020] [Citation(s) in RCA: 257] [Impact Index Per Article: 64.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 03/27/2020] [Accepted: 03/27/2020] [Indexed: 01/08/2023] Open
Abstract
Patients with hypertension, diabetes, coronary heart disease, cerebrovascular illness, chronic obstructive pulmonary disease, and kidney dysfunction have worse clinical outcomes when infected with SARS-CoV-2, for unknown reasons. The purpose of this review is to summarize the evidence for the existence of elevated plasmin(ogen) in COVID-19 patients with these comorbid conditions. Plasmin, and other proteases, may cleave a newly inserted furin site in the S protein of SARS-CoV-2, extracellularly, which increases its infectivity and virulence. Hyperfibrinolysis associated with plasmin leads to elevated D-dimer in severe patients. The plasmin(ogen) system may prove a promising therapeutic target for combating COVID-19.
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Affiliation(s)
- Hong-Long Ji
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas; Texas Lung Injury Institute, University of Texas Health Science Centre at Tyler, Tyler, Texas; Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Medicine and Anesthesia, University of California San Francisco, San Francisco, California
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas; Texas Lung Injury Institute, University of Texas Health Science Centre at Tyler, Tyler, Texas; Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Medicine and Anesthesia, University of California San Francisco, San Francisco, California
| | - Sadis Matalon
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas; Texas Lung Injury Institute, University of Texas Health Science Centre at Tyler, Tyler, Texas; Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Medicine and Anesthesia, University of California San Francisco, San Francisco, California
| | - Michael A Matthay
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas; Texas Lung Injury Institute, University of Texas Health Science Centre at Tyler, Tyler, Texas; Department of Anesthesiology and Perioperative Medicine, Division of Molecular and Translational Biomedicine, Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Medicine and Anesthesia, University of California San Francisco, San Francisco, California
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17
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Zhao R, Ali G, Nie HG, Chang Y, Bhattarai D, Su X, Zhao X, Matthay MA, Ji HL. Plasmin improves blood-gas barrier function in oedematous lungs by cleaving epithelial sodium channels. Br J Pharmacol 2020; 177:3091-3106. [PMID: 32133621 DOI: 10.1111/bph.15038] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 02/11/2020] [Accepted: 02/25/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Lung oedema in association with suppressed fibrinolysis is a hallmark of lung injury. Here, we have tested whether plasmin cleaves epithelial sodium channels (ENaC) to resolve lung oedema fluid. EXPERIMENTAL APPROACH Human lungs and airway acid-instilled mice were used for analysing fluid resolution. In silico prediction, mutagenesis, Xenopus oocytes, immunoblotting, voltage clamp, mass spectrometry, and protein docking were combined for identifying plasmin cleavage sites. KEY RESULTS Plasmin improved lung fluid resolution in both human lungs ex vivo and injured mice. Plasmin activated αβγENaC channels in oocytes in a time-dependent manner. Deletion of four consensus proteolysis tracts (αΔ432-444, γΔ131-138, γΔ178-193, and γΔ410-422) eliminated plasmin-induced activation significantly. Further, immunoblotting assays identified 7 cleavage sites (K126, R135, K136, R153, K168, R178, K179) for plasmin to trim both furin-cleaved C-terminal fragments and full-length human γENaC proteins. In addition, 9 new sites (R122, R137, R138, K150, K170, R172, R180, K181, K189) in synthesized peptides were found to be cleaved by plasmin. These cleavage sites were located in the finger and the thumb, particularly the GRIP domain of human ENaC 3D model composed of two proteolytic centres for plasmin. Novel uncleaved sites beyond the GRIP domain in both α and γ subunits were identified to interrupt the plasmin cleavage-induced conformational change in ENaC channel complexes. Additionally, plasmin could regulate ENaC activity via the G protein signal. CONCLUSION AND IMPLICATIONS Plasmin can cleave ENaC to improve blood-gas exchange by resolving oedema fluid and could be a potent therapy for oedematous lungs.
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Affiliation(s)
- Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas
| | - Gibran Ali
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas
| | - Hong-Guang Nie
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas.,College of Basic Medical Science, China Medical University, Shenyang, Liaoning, China
| | - Yongchang Chang
- Division of Neurobiology, Barrow Neurological Institute, Phoenix, Arizona
| | - Deepa Bhattarai
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas
| | - Xuefeng Su
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas
| | - Xiaoli Zhao
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, Virginia
| | - Michael A Matthay
- Department of Medicine and Anesthesia, University of California San Francisco, San Francisco, California
| | - Hong-Long Ji
- Department of Cellular and Molecular Biology, University of Texas Health Science Centre at Tyler, Tyler, Texas.,Texas Lung Injury Institute, University of Texas Health Science Centre at Tyler, Tyler, Texas
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18
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Bohnert BN, Daiminger S, Wörn M, Sure F, Staudner T, Ilyaskin AV, Batbouta F, Janessa A, Schneider JC, Essigke D, Kanse S, Haerteis S, Korbmacher C, Artunc F. Urokinase-type plasminogen activator (uPA) is not essential for epithelial sodium channel (ENaC)-mediated sodium retention in experimental nephrotic syndrome. Acta Physiol (Oxf) 2019; 227:e13286. [PMID: 31006168 DOI: 10.1111/apha.13286] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/10/2019] [Accepted: 04/15/2019] [Indexed: 12/17/2022]
Abstract
AIM In nephrotic syndrome, aberrantly filtered plasminogen (plg) is converted to active plasmin by tubular urokinase-type plasminogen activator (uPA) and thought to lead to sodium retention by proteolytic activation of the epithelial sodium channel (ENaC). This concept predicts that uPA is an important factor for sodium retention and that inhibition of uPA might be protective in nephrotic syndrome. METHODS Activation of amiloride-sensitive currents by uPA and plg were studied in Xenopus laevis oocytes expressing murine ENaC. In doxorubicin-induced nephrotic mice, uPA was inhibited pharmacologically by amiloride and genetically by the use of uPA-deficient mice (uPA-/- ). RESULTS Experiments in Xenopus laevis oocytes expressing murine ENaC confirmed proteolytic ENaC activation by a combination of plg and uPA which stimulated amiloride-sensitive currents with concomitant cleavage of the ENaC γ-subunit at the cell surface. Treatment of nephrotic wild-type mice with amiloride inhibited urinary uPA activity, prevented urinary plasmin formation and sodium retention. In nephrotic mice lacking uPA (uPA-/- ), urinary plasmin formation from plg was suppressed and urinary uPA activity absent. However, in nephrotic uPA-/- mice, sodium retention was not reduced compared to nephrotic uPA+/+ mice. Amiloride prevented sodium retention in nephrotic uPA-/- mice which confirmed the critical role of ENaC in sodium retention. CONCLUSION uPA is responsible for the conversion of aberrantly filtered plasminogen to plasmin in the tubular lumen in vivo. However, uPA-dependent plasmin generation is not essential for ENaC-mediated sodium retention in experimental nephrotic syndrome.
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Affiliation(s)
- Bernhard N. Bohnert
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tübingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tübingen Germany
| | - Sophie Daiminger
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Matthias Wörn
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Florian Sure
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Bayern Germany
| | - Tobias Staudner
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Bayern Germany
| | - Alexandr V. Ilyaskin
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Bayern Germany
| | - Firas Batbouta
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Andrea Janessa
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Jonas C. Schneider
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Daniel Essigke
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
| | - Sandip Kanse
- Institute of Basic Medical Sciences University of Oslo Oslo Norway
| | - Silke Haerteis
- Institute of Anatomy University of Regensburg Regensburg Germany
| | - Christoph Korbmacher
- Institute of Cellular and Molecular Physiology Friedrich‐Alexander University Erlangen‐Nürnberg (FAU) Bayern Germany
| | - Ferruh Artunc
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry University Hospital Tübingen Tübingen Germany
- Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University Tübingen Tübingen Germany
- German Center for Diabetes Research (DZD) at the University Tübingen Tübingen Germany
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19
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Hinrichs GR, Weyer K, Friis UG, Svenningsen P, Lund IK, Nielsen R, Mollet G, Antignac C, Bistrup C, Jensen BL, Birn H. Urokinase-type plasminogen activator contributes to amiloride-sensitive sodium retention in nephrotic range glomerular proteinuria in mice. Acta Physiol (Oxf) 2019; 227:e13362. [PMID: 31423748 DOI: 10.1111/apha.13362] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 08/12/2019] [Accepted: 08/15/2019] [Indexed: 12/12/2022]
Abstract
AIM Activation of sodium reabsorption by urinary proteases has been implicated in sodium retention associated with nephrotic syndrome. The study was designed to test the hypothesis that nephrotic proteinuria in mice after conditional deletion of podocin leads to urokinase-dependent, amiloride-sensitive plasmin-mediated sodium and water retention. METHODS Ten days after podocin knockout, urine and faeces were collected for 10 days in metabolic cages and analysed for electrolytes, plasminogen, protease activity and ability to activate γENaC by patch clamp and western blot. Mice were treated with amiloride (2.5 mg kg-1 for 2 days and 10 mg kg-1 for 2 days) or an anti-urokinase-type plasminogen activator (uPA) targeting antibody (120 mg kg-1 /24 h) and compared to controls. RESULTS Twelve days after deletion, podocin-deficient mice developed significant protein and albuminuria associated with increased body wt, ascites, sodium accumulation and suppressed plasma renin. This was associated with increased urinary excretion of plasmin and plasminogen that correlated with albumin excretion, urine protease activity co-migrating with active plasmin, and the ability of urine to induce an amiloride-sensitive inward current in M1 cells in vitro. Amiloride treatment in podocin-deficient mice resulted in weight loss, increased sodium excretion, normalization of sodium balance and prevention of the activation of plasminogen to plasmin in urine in a reversible way. Administration of uPA targeting antibody abolished urine activation of plasminogen, attenuated sodium accumulation and prevented cleavage of γENaC. CONCLUSIONS Nephrotic range glomerular proteinuria leads to urokinase-dependent intratubular plasminogen activation and γENaC cleavage which contribute to sodium accumulation.
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Affiliation(s)
- Gitte R. Hinrichs
- Department of Molecular Medicine, Cardiovascular and Renal Research University of Southern Denmark Odense Denmark
| | - Kathrin Weyer
- Department of Biomedicine Aarhus University Aarhus Denmark
| | - Ulla G. Friis
- Department of Molecular Medicine, Cardiovascular and Renal Research University of Southern Denmark Odense Denmark
| | - Per Svenningsen
- Department of Molecular Medicine, Cardiovascular and Renal Research University of Southern Denmark Odense Denmark
| | - Ida K. Lund
- The Finsen Laboratory Rigshospitalet Copenhagen Denmark
- Biotech Research & Innovation Centre (BRIC) University of Copenhagen Copenhagen Denmark
| | - Rikke Nielsen
- Department of Biomedicine Aarhus University Aarhus Denmark
| | - Géraldine Mollet
- Laboratory of Hereditary Kidney Diseases Imagine Institute Inserm, U1163 Paris Descartes‐Sorbonne Paris Cité University Paris France
| | - Corinne Antignac
- Laboratory of Hereditary Kidney Diseases Imagine Institute Inserm, U1163 Paris Descartes‐Sorbonne Paris Cité University Paris France
- Department of Genetics Necker Hospital Assistance Publique‐Hôpitaux de Paris Paris France
| | - Claus Bistrup
- Department of Nephrology Odense University Hospital Odense Denmark
- Department of Clinical Research University of Southern Denmark Odense Denmark
| | - Boye L. Jensen
- Department of Molecular Medicine, Cardiovascular and Renal Research University of Southern Denmark Odense Denmark
| | - Henrik Birn
- Department of Biomedicine Aarhus University Aarhus Denmark
- Department of Renal Medicine Aarhus University Hospital Aarhus Denmark
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Abstract
Epithelial Na+ channels (ENaCs) are members of a family of cation channels that function as sensors of the extracellular environment. ENaCs are activated by specific proteases in the biosynthetic pathway and at the cell surface and remove embedded inhibitory tracts, which allows channels to transition to higher open-probability states. Resolved structures of ENaC and an acid-sensing ion channel revealed highly organized extracellular regions. Within the periphery of ENaC subunits are unique domains formed by antiparallel β-strands containing the inhibitory tracts and protease cleavage sites. ENaCs are inhibited by Na+ binding to specific extracellular site(s), which promotes channel transition to a lower open-probability state. Specific inositol phospholipids and channel modification by Cys-palmitoylation enhance channel open probability. How these regulatory factors interact in a concerted manner to influence channel open probability is an important question that has not been resolved. These various factors are reviewed, and the impact of specific factors on human disorders is discussed.
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Affiliation(s)
- Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, and Departments of Cell Biology and of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Douglas C Eaton
- Division of Nephrology, Department of Medicine, Emory University, Atlanta, Georgia
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21
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Zhao R, Ali G, Chang J, Komatsu S, Tsukasaki Y, Nie HG, Chang Y, Zhang M, Liu Y, Jain K, Jung BG, Samten B, Jiang D, Liang J, Ikebe M, Matthay MA, Ji HL. Proliferative regulation of alveolar epithelial type 2 progenitor cells by human Scnn1d gene. Am J Cancer Res 2019; 9:8155-8170. [PMID: 31754387 PMCID: PMC6857051 DOI: 10.7150/thno.37023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 09/16/2019] [Indexed: 01/03/2023] Open
Abstract
Lung epithelial sodium channel (ENaC) encoded by Scnn1 genes is essential for maintaining transepithelial salt and fluid homeostasis in the airway and the lung. Compared to α, β, and γ subunits, the role of respiratory δ-ENaC has not been studied in vivo due to the lack of animal models. Methods: We characterized full-length human δ802-ENaC expressed in both Xenopus oocytes and humanized transgenic mice. AT2 proliferation and differentiation in 3D organoids were analysed with FACS and a confocal microscope. Both two-electrode voltage clamp and Ussing chamber systems were applied to digitize δ802-ENaC channel activity. Immunoblotting was utilized to analyse δ802-ENaC protein. Transcripts of individual ENaC subunits in human lung tissues were quantitated with qPCR. Results: The results indicate that δ802-ENaC functions as an amiloride-inhibitable Na+ channel. Inhibitory peptide α-13 distinguishes δ802- from α-type ENaC channels. Modified proteolysis of γ-ENaC by plasmin and aprotinin did not alter the inhibition of amiloride and α-13 peptide. Expression of δ802-ENaC at the apical membrane of respiratory epithelium was detected with biophysical features similar to those of heterologously expressed channels in oocytes. δ802-ENaC regulated alveologenesis through facilitating the proliferation of alveolar type 2 epithelial cells. Conclusion: The humanized mouse line conditionally expressing human δ802-ENaC is a novel model for studying the expression and function of this protein in vivo .
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22
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Mutchler SM, Kleyman TR. New insights regarding epithelial Na+ channel regulation and its role in the kidney, immune system and vasculature. Curr Opin Nephrol Hypertens 2019; 28:113-119. [PMID: 30585851 PMCID: PMC6349474 DOI: 10.1097/mnh.0000000000000479] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PURPOSE OF REVIEW This review describes recent findings regarding the epithelial Na channel (ENaC) and its roles in physiologic and pathophysiologic states. We discuss new insights regarding ENaC's structure, its regulation by various factors, its potential role in hypertension and nephrotic syndrome, and its roles in the immune system and vasculature. RECENT FINDINGS A recently resolved structure of ENaC provides clues regarding mechanisms of ENaC activation by proteases. The use of amiloride in nephrotic syndrome, and associated complications are discussed. ENaC is expressed in dendritic cells and contributes to immune system activation and increases in blood pressure in response to NaCl. ENaC is expressed in endothelial ENaC and has a role in regulating vascular tone. SUMMARY New findings have emerged regarding ENaC and its role in the kidney, immune system, and vasculature.
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Affiliation(s)
- Stephanie M. Mutchler
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA
| | - Thomas R. Kleyman
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA
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Alveolar type 2 progenitor cells for lung injury repair. Cell Death Discov 2019; 5:63. [PMID: 30774991 PMCID: PMC6368612 DOI: 10.1038/s41420-019-0147-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 12/24/2018] [Accepted: 01/02/2019] [Indexed: 12/19/2022] Open
Abstract
Alveolar type 2 progenitor cells (AT2) seem closest to clinical translation, specifying the evidence that AT2 may satisfactorily control the immune response to decrease lung injury by stabilizing host immune-competence and a classic and crucial resource for lung regeneration and repair. AT2 establish potential in benefiting injured lungs. However, significant discrepancies linger in our understanding vis-à-vis the mechanisms for AT2 as a regime for stem cell therapy as well as essential guiding information for clinical trials, including effectiveness in appropriate pre-clinical models, safety, mostly specifications for divergent lung injury patients. These important gaps shall be systematically investigated prior to the vast therapeutic perspective of AT2 cells for pulmonary diseases can be considered. This review focused on AT2 cells homeostasis, pathophysiological changes in the pathogenesis of lung injury, physiological function of AT2 cells, apoptosis of AT2 cells in lung diseases, the role of AT2 cells in repairing processes after lung injury, mechanism of AT2 cells activation promote repairing processes after lung injury, and potential therapy of lung disease by utilizing the AT2 progenitor cells. The advancement remains to causally connect the molecular and cellular alteration of AT2 cells to lung injury and repair. Conclusively, it is identified that AT2 cells can convert into AT1 cells; but, the comprehensive cellular mechanisms involved in this transition are unrevealed. Further investigation is mandatory to determine new strategies to prevent lung injury.
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Joslyn LR, Pienaar E, DiFazio RM, Suliman S, Kagina BM, Flynn JL, Scriba TJ, Linderman JJ, Kirschner DE. Integrating Non-human Primate, Human, and Mathematical Studies to Determine the Influence of BCG Timing on H56 Vaccine Outcomes. Front Microbiol 2018; 9:1898. [PMID: 30177934 PMCID: PMC6110197 DOI: 10.3389/fimmu.2018.01898] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/31/2018] [Indexed: 12/21/2022] Open
Abstract
Background Acute lung injury (ALI) is characterized by suppressed fibrinolytic activity in bronchoalveolar lavage fluid (BALF) attributed to elevated plasminogen activator inhibitor-1 (PAI-1). Restoring pulmonary fibrinolysis by delivering tissue-type plasminogen activator (tPA), urokinase plasminogen activator (uPA), and plasmin could be a promising approach. Objectives To systematically analyze the overall benefit of fibrinolytic therapy for ALI reported in preclinical studies. Methods We searched PubMed, Embase, Web of Science, and CNKI Chinese databases, and analyzed data retrieved from 22 studies for the beneficial effects of fibrinolytics on animal models of ALI. Results Both large and small animals were used with five routes for delivering tPA, uPA, and plasmin. Fibrinolytics significantly increased the fibrinolytic activity both in the plasma and BALF. Fibrin degradation products in BALF had a net increase of 408.41 ng/ml vs controls (P < 0.00001). In addition, plasma thrombin–antithrombin complexes increased 1.59 ng/ml over controls (P = 0.0001). In sharp contrast, PAI-1 level in BALF decreased 21.44 ng/ml compared with controls (P < 0.00001). Arterial oxygen tension was improved by a net increase of 15.16 mmHg, while carbon dioxide pressure was significantly reduced (11.66 mmHg, P = 0.0001 vs controls). Additionally, fibrinolytics improved lung function and alleviated inflammation response: the lung wet/dry ratio was decreased 1.49 (P < 0.0001 vs controls), lung injury score was reduced 1.83 (P < 0.00001 vs controls), and BALF neutrophils were lesser (3 × 104/ml, P < 0.00001 vs controls). The mortality decreased significantly within defined study periods (6 h to 30 days for mortality), as the risk ratio of death was 0.2-fold of controls (P = 0.0008). Conclusion We conclude that fibrinolytic therapy may be effective pharmaceutic strategy for ALI in animal models.
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Affiliation(s)
- Louis R Joslyn
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, United States.,Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Elsje Pienaar
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, United States.,Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Robert M DiFazio
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sara Suliman
- South African Tuberculosis Vaccine Initiative and Institute of Infectious Disease and Molecular Medicine, Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Benjamin M Kagina
- South African Tuberculosis Vaccine Initiative and Institute of Infectious Disease and Molecular Medicine, Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - JoAnne L Flynn
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Thomas J Scriba
- South African Tuberculosis Vaccine Initiative and Institute of Infectious Disease and Molecular Medicine, Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Jennifer J Linderman
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, United States
| | - Denise E Kirschner
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
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Lee JD, Chung LY, Lin RJ, Wang JJ, Tu HP, Yen CM. Excretory/secretory proteases and mechanical movement of Anisakis pegreffii infective larvae in the penetration of BALB/c mice gastrointestine. Kaohsiung J Med Sci 2017; 33:594-601. [PMID: 29132548 DOI: 10.1016/j.kjms.2017.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/28/2017] [Accepted: 08/08/2017] [Indexed: 01/23/2023] Open
Abstract
Anisakiasis is a human parasitic disease caused by infection with the infective larvae of Anisakis. Accidental infection in humans causes the gastrointestinal pathophysiological effects of mechanical tissue damage by migrating larvae. The mechanism of the infective larval invasion and migration is suspected to involve larval excretory/secretory proteases and motility. This study demonstrates the penetration rate of the infective larvae of Anisakis pegreffii in mouse gastrointestine depends on the time after infection, and that only 15% of larvae remain in the gastrointestinal tract 3 h after infection. Strong activities of matrix metalloproteinases (MMPs) and serine proteases, especially plasmin, were found in the excretory/secretory products of A. pegreffii; these can be inhibited by ONO-4817 and phenylmethylsulfonyl fluoride, respectively. The protease activity was also significantly decreased in another 1 h of cultivation of larvae in fresh 0.9% normal saline (NS) after previous cultivation for 48 h in NS. The motility scores of larvae were significantly lower after 48 h of cultivation in NS. The penetration rate of A. pegreffii larvae in the gastrointestine of infected mice sequentially were 90% in the freshly prepared, 68% in serine protease inhibited, 55% in MMPs inhibited larvae, and 16% in larvae cultivated in NS for 48 h. Therefore, this study demonstrates that MMPs and serine proteases excreted and secreted by A. pegreffii and the mechanical movement of infective larvae participate in the penetration of the gastrointestine of mice after infection.
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Affiliation(s)
- June-Der Lee
- Department of Parasitology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Li-Yu Chung
- Department of Parasitology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Rong-Jyh Lin
- Department of Parasitology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Jiun-Jye Wang
- Department of Parasitology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Hong-Pin Tu
- Department of Public Health and Environment Medicine, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chuan-Min Yen
- Department of Parasitology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
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26
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Roldán-Olarte M, Maillo V, Sánchez-Calabuig MJ, Beltrán-Breña P, Rizos D, Gutiérrez-Adán A. Effect of urokinase type plasminogen activator on in vitro bovine oocyte maturation. Reproduction 2017; 154:231-240. [PMID: 28667127 DOI: 10.1530/rep-17-0204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 05/23/2017] [Accepted: 06/30/2017] [Indexed: 12/27/2022]
Abstract
This study examines the impacts of the urokinase-type plasminogen activator (uPA) on the in vitro maturation (IVM) of bovine oocytes. Cumulus-oocyte complexes in IVM medium were treated with uPA, amiloride (an uPA inhibitor), dimethyl sulfoxide (DMSO) or left untreated (control group). After 24 h of IVM, oocytes were recovered for testing or were in vitro fertilized and cultured to the blastocyst stage. The factors examined in all groups were: (i) oocyte nuclear maturation (Hoëscht staining); (ii) oocyte cytoplasmic maturation (cortical granules, CGs, distribution assessed by LCA-FITC); (iii) oocyte and cumulus cell (CC) gene expression (RT-qPCR); and (iv) embryo development (cleavage rate and blastocyst yield). Oocytes subjected to uPA treatment showed rates of nuclear maturation and CG distribution patterns similar to controls (P > 0.05), whereas lower rates of oocyte maturation were recorded in the amiloride group (P < 0.05). Both in oocytes and CC, treatment with uPA did not affect the transcription of genes related to apoptosis, cell junctions, cell cycle or serpin protease inhibitors. In contrast, amiloride altered the expression of genes associated with cell junctions, cell cycle, oxidative stress and CC serpins. No differences were observed between the control and uPA group in cleavage rate or in blastocyst yield recorded on Days 7, 8 or 9 post-insemination. However, amiloride led to drastically reduced cleavage rate (28.5% vs 83.2%) and Day 9 embryo production (6.0% vs 21.0%) over the rates recorded for DMSO. These results indicate that the proteolytic activity of uPA is needed for successful oocyte maturation in bovine.
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Affiliation(s)
- Mariela Roldán-Olarte
- Department Reproducción AnimalINIA, Madrid, Spain .,Instituto Superior de Investigaciones Biológicas (INSIBIO)CONICET-Universidad Nacional de Tucumán (UNT), San Miguel de Tucumán, Argentina
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27
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Svenningsen P, Hinrichs GR, Zachar R, Ydegaard R, Jensen BL. Physiology and pathophysiology of the plasminogen system in the kidney. Pflugers Arch 2017; 469:1415-1423. [DOI: 10.1007/s00424-017-2014-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/09/2017] [Accepted: 06/12/2017] [Indexed: 12/31/2022]
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28
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Marked increases in mucociliary clearance produced by synergistic secretory agonists or inhibition of the epithelial sodium channel. Sci Rep 2016; 6:36806. [PMID: 27830759 PMCID: PMC5103292 DOI: 10.1038/srep36806] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 10/21/2016] [Indexed: 12/11/2022] Open
Abstract
Mucociliary clearance (MCC) is a critical host innate defense mechanism in airways, and it is impaired in cystic fibrosis (CF) and other obstructive lung diseases. Epithelial fluid secretion and absorption modify MCC velocity (MCCV). We tested the hypotheses that inhibiting fluid absorption accelerates MCCV, whereas inhibiting fluid secretion decelerates it. In airways, ENaC is mainly responsible for fluid absorption, while anion channels, including CFTR and Ca2+-activated chloride channels mediate anion/fluid secretion. MCCV was increased by the cAMP-elevating agonists, forskolin or isoproterenol (10 μM) and by the Ca2+-elevating agonist, carbachol (0.3 μM). The CFTR-selective inhibitor, CFTRinh-172, modestly reduced MCCV-increases induced by forskolin or isoproterenol but not increases induced by carbachol. The ENaC inhibitor benzamil increased basal MCCV as well as MCCV increases produced by forskolin or carbachol. MCC velocity was most dramatically accelerated by the synergistic combination of forskolin and carbachol, which produced near-maximal clearance rates regardless of prior treatment with CFTR or ENaC inhibitors. In CF airways, where CFTR-mediated secretion (and possibly synergistic MCC) is lost, ENaC inhibition via exogenous agents may provide therapeutic benefit, as has long been proposed.
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Nielsen LH, Ovesen P, Hansen MR, Brantlov S, Jespersen B, Bie P, Jensen BL. Changes in the renin-angiotensin-aldosterone system in response to dietary salt intake in normal and hypertensive pregnancy. A randomized trial. ACTA ACUST UNITED AC 2016; 10:881-890.e4. [DOI: 10.1016/j.jash.2016.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/29/2016] [Accepted: 10/09/2016] [Indexed: 12/31/2022]
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Boscardin E, Alijevic O, Hummler E, Frateschi S, Kellenberger S. The function and regulation of acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC): IUPHAR Review 19. Br J Pharmacol 2016; 173:2671-701. [PMID: 27278329 DOI: 10.1111/bph.13533] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/19/2016] [Accepted: 06/02/2016] [Indexed: 12/30/2022] Open
Abstract
Acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC) are both members of the ENaC/degenerin family of amiloride-sensitive Na(+) channels. ASICs act as proton sensors in the nervous system where they contribute, besides other roles, to fear behaviour, learning and pain sensation. ENaC mediates Na(+) reabsorption across epithelia of the distal kidney and colon and of the airways. ENaC is a clinically used drug target in the context of hypertension and cystic fibrosis, while ASIC is an interesting potential target. Following a brief introduction, here we will review selected aspects of ASIC and ENaC function. We discuss the origin and nature of pH changes in the brain and the involvement of ASICs in synaptic signalling. We expose how in the peripheral nervous system, ASICs cover together with other ion channels a wide pH range as proton sensors. We introduce the mechanisms of aldosterone-dependent ENaC regulation and the evidence for an aldosterone-independent control of ENaC activity, such as regulation by dietary K(+) . We then provide an overview of the regulation of ENaC by proteases, a topic of increasing interest over the past few years. In spite of the profound differences in the physiological and pathological roles of ASICs and ENaC, these channels share many basic functional and structural properties. It is likely that further research will identify physiological contexts in which ASICs and ENaC have similar or overlapping roles.
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Affiliation(s)
- Emilie Boscardin
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Omar Alijevic
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
| | - Edith Hummler
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland
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31
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Su Z, Zhu L, Wu J, Zhao R, Ji HL. Systematic review and meta-analysis of nasal potential difference in hypoxia-induced lung injury. Sci Rep 2016; 6:30780. [PMID: 27488696 PMCID: PMC4973263 DOI: 10.1038/srep30780] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 07/07/2016] [Indexed: 12/27/2022] Open
Abstract
Nasal potential difference (NPD), a well-established in vivo clinical test for cystic fibrosis, reflects transepithelial cation and anion transport in the respiratory epithelium. To analyze whether NPD can be applied to diagnose hypoxic lung injury, we searched PubMed, EMBASE, Scopus, Web of Science, Ovid MEDLINE, and Google Scholar, and analyzed data retrieved from eleven unbiased studies for high altitude pulmonary edema (HAPE) and respiratory distress syndrome (RDS) using the software RevMan and R. There was a significant reduction in overall basal (WMD -5.27 mV, 95% CI: -6.03 to -4.52, P < 0.00001, I(2) = 42%), amiloride-sensitive (ENaC) (-2.87 mV, 95% CI: -4.02 to -1.72, P < 0.00001, I(2) = 51%), and -resistant fractions (-3.91 mV, 95% CI: -7.64 to -0.18, P = 0.04, I(2) = 95%) in lung injury patients. Further analysis of HAPE and RDS separately corroborated these observations. Moreover, SpO2 correlated with ENaC-associated NPD positively in patients only, but apparently related to CFTR-contributed NPD level inversely. These correlations were confirmed by the opposite associations between NPD values and altitude, which had a negative regression with SpO2 level. Basal NPD was significantly associated with amiloride-resistant but not ENaC fraction. Our analyses demonstrate that acute lung injury associated with systemic hypoxia is characterized by dysfunctional NPD.
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Affiliation(s)
- Zhenlei Su
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan 453003, China.,School of Public Health, Xinxiang Medical University, Xinxiang Henan, 453003, China
| | - Lili Zhu
- School of Nursing, Xinxiang Medical University, Xinxiang Henan 453003, China
| | - Jing Wu
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan 453003, China
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas, 75708, USA
| | - Hong-Long Ji
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, Texas, 75708, USA.,Texas Lung Injury Institute, University of Texas Health Science Center at Tyler, Tyler, Texas, 75708, USA
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Abstract
Objective: To focus on the asthmatic pathogenesis and clinical manifestations related to epithelial sodium channel (ENaC)/chlorine ion channel. Data Sources: The data analyzed in this review were the English articles from 1980 to 2015 from journal databases, primarily PubMed and Google Scholar. The terms used in the literature search were: (1) ENaCs; cystic fibrosis (CF) transmembrane conductance regulator (CFTR); asthma/asthmatic, (2) ENaC/sodium salt; CF; asthma/asthmatic, (3) CFTR/chlorine ion channels; asthma/asthmatic, (4) ENaC/sodium channel/scnn1a/scnn1b/scnn1g/scnn1d/amiloride-sensitive/amiloride-inhibtable sodium channels/sodium salt; asthma/asthmatic, lung/pulmonary/respiratory/tracheal/alveolar, and (5) CFTR; CF; asthma/asthmatic (ti). Study Selection: These studies included randomized controlled trials or studies covering asthma pathogenesis and clinical manifestations related to ENaC/chlorine ion channels within the last 25 years (from 1990 to 2015). The data involving chronic obstructive pulmonary disease and CF obtained from individual studies were also reviewed by the authors. Results: Airway surface liquid dehydration can cause airway inflammation and obstruction. ENaC and CFTR are closely related to the airway mucociliary clearance. Ion transporters may play a critical role in pathogenesis of asthmatic exacerbations. Conclusions: Ion channels have been the center of many studies aiming to understand asthmatic pathophysiological mechanisms or to identify therapeutic targets for better control of the disease.
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Affiliation(s)
- Wen Wang
- Department of Respiratory and Critical Care Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing Institute of Respiratory Medicine, Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders, Beijing 100020, China; Department of Cellular and Molecular Biology, Texas Lung Injury Institute, University of Texas Health Science Center at Tyler, Tyler Texas 75708, USA,
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Almholt K, Lærum OD, Nielsen BS, Lund IK, Lund LR, Rømer J, Jögi A. Spontaneous lung and lymph node metastasis in transgenic breast cancer is independent of the urokinase receptor uPAR. Clin Exp Metastasis 2015; 32:543-54. [PMID: 26040548 DOI: 10.1007/s10585-015-9726-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 05/28/2015] [Indexed: 02/06/2023]
Abstract
Urokinase-type plasminogen activator (uPA) is an extracellular protease that plays a pivotal role in tumor progression. uPA activity is spatially restricted by its anchorage to high-affinity uPA receptors (uPAR) at the cell surface. High tumor tissue expression of uPA and uPAR is associated with poor prognosis in lung, breast, and colon cancer patients in clinical studies. Genetic deficiency of uPA leads to a significant reduction in metastases in the murine transgenic MMTV-PyMT breast cancer model, demonstrating a causal role for uPA in cancer dissemination. To investigate the role of uPAR in cancer progression, we analyze the effect of uPAR deficiency in the same cancer model. uPAR is predominantly expressed in stromal cells in the mouse primary tumors, similar to human breast cancer. In a cohort of MMTV-PyMT mice [uPAR-deficient (n = 31) or wild type controls (n = 33)], tumorigenesis, tumor growth, and tumor histopathology were not significantly affected by uPAR deficiency. Lung and lymph node metastases were also not significantly affected by uPAR deficiency, in contrast to the significant reduction seen in uPA-deficient mice. Taken together, our data show that the genetic absence of uPAR does not influence the outcome of the MMTV-PyMT cancer model.
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Affiliation(s)
- Kasper Almholt
- The Finsen Laboratory, Rigshospitalet, Copenhagen, Denmark,
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34
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Stæhr M, Buhl KB, Andersen RF, Svenningsen P, Nielsen F, Hinrichs GR, Bistrup C, Jensen BL. Aberrant glomerular filtration of urokinase-type plasminogen activator in nephrotic syndrome leads to amiloride-sensitive plasminogen activation in urine. Am J Physiol Renal Physiol 2015; 309:F235-41. [PMID: 25972510 DOI: 10.1152/ajprenal.00138.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/07/2015] [Indexed: 01/11/2023] Open
Abstract
In nephrotic syndrome, aberrant glomerular filtration of plasminogen and conversion to active plasmin in preurine are thought to activate proteolytically epithelial sodium channel (ENaC) and contribute to sodium retention and edema. The ENaC blocker amiloride is an off-target inhibitor of urokinase-type plasminogen activator (uPA) in vitro. It was hypothesized that uPA is abnormally filtered to preurine and is inhibited in urine by amiloride in nephrotic syndrome. This was tested by determination of Na(+) balance, uPA protein and activity, and amiloride concentration in urine from rats with puromycin aminonucleoside (PAN)-induced nephrotic syndrome. Urine samples from 6 adult and 18 pediatric patients with nephrotic syndrome were analyzed for uPA activity and protein. PAN treatment induced significant proteinuria in rats which coincided with increased urine uPA protein and activity, increased urine protease activity, and total plasminogen/plasmin concentration and Na(+) retention. Amiloride (2 mg·kg(-1)·24 h(-1)) concentration in urine was in the range 10-20 μmol/l and reduced significantly urine uPA activity, plasminogen activation, protease activity, and sodium retention in PAN rats, while proteinuria was not altered. In paired urine samples, uPA protein was significantly elevated in urine from children with active nephrotic syndrome compared with remission phase. In six adult nephrotic patients, urine uPA protein and activity correlated positively with 24 h urine protein excretion. In conclusion, nephrotic syndrome is associated with aberrant filtration of uPA across the injured glomerular barrier. Amiloride inhibits urine uPA activity which attenuates plasminogen activation and urine protease activity in vivo. Urine uPA is a relevant target for amiloride in vivo.
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Affiliation(s)
- Mette Stæhr
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Kristian B Buhl
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - René F Andersen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
| | - Per Svenningsen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Flemming Nielsen
- Clinical Pharmacology, Institute of Public Health, University of Southern Denmark, Odense, Denmark; and
| | | | - Claus Bistrup
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Department of Nephrology, Odense University Hospital, Odense, Denmark
| | - Boye L Jensen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark;
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