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The Cultivation Modality and Barrier Maturity Modulate the Toxicity of Industrial Zinc Oxide and Titanium Dioxide Nanoparticles on Nasal, Buccal, Bronchial, and Alveolar Mucosa Cell-Derived Barrier Models. Int J Mol Sci 2023; 24:ijms24065634. [PMID: 36982705 PMCID: PMC10056597 DOI: 10.3390/ijms24065634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/07/2023] [Accepted: 03/12/2023] [Indexed: 03/18/2023] Open
Abstract
As common industrial by-products, airborne engineered nanomaterials are considered important environmental toxins to monitor due to their potential health risks to humans and animals. The main uptake routes of airborne nanoparticles are nasal and/or oral inhalation, which are known to enable the transfer of nanomaterials into the bloodstream resulting in the rapid distribution throughout the human body. Consequently, mucosal barriers present in the nose, buccal, and lung have been identified and intensively studied as the key tissue barrier to nanoparticle translocation. Despite decades of research, surprisingly little is known about the differences among various mucosa tissue types to tolerate nanoparticle exposures. One limitation in comparing nanotoxicological data sets can be linked to a lack of harmonization and standardization of cell-based assays, where (a) different cultivation conditions such as an air-liquid interface or submerged cultures, (b) varying barrier maturity, and (c) diverse media substitutes have been used. The current comparative nanotoxicological study, therefore, aims at analyzing the toxic effects of nanomaterials on four human mucosa barrier models including nasal (RPMI2650), buccal (TR146), alveolar (A549), and bronchial (Calu-3) mucosal cell lines to better understand the modulating effects of tissue maturity, cultivation conditions, and tissue type using standard transwell cultivations at liquid-liquid and air-liquid interfaces. Overall, cell size, confluency, tight junction localization, and cell viability as well as barrier formation using 50% and 100% confluency was monitored using trans-epithelial-electrical resistance (TEER) measurements and resazurin-based Presto Blue assays of immature (e.g., 5 days) and mature (e.g., 22 days) cultures in the presence and absence of corticosteroids such as hydrocortisone. Results of our study show that cellular viability in response to increasing nanoparticle exposure scenarios is highly compound and cell-type specific (TR146 6 ± 0.7% at 2 mM ZnO (ZnO) vs. ~90% at 2 mM TiO2 (TiO2) for 24 h; Calu3 93.9 ± 4.21% at 2 mM ZnO vs. ~100% at 2 mM TiO2). Nanoparticle-induced cytotoxic effects under air-liquid cultivation conditions declined in RPMI2650, A549, TR146, and Calu-3 cells (~0.7 to ~0.2-fold), with increasing 50 to 100% barrier maturity under the influence of ZnO (2 mM). Cell viability in early and late mucosa barriers where hardly influenced by TiO2 as well as most cell types did not fall below 77% viability when added to Individual ALI cultures. Fully maturated bronchial mucosal cell barrier models cultivated under ALI conditions showed less tolerance to acute ZnO nanoparticle exposures (~50% remaining viability at 2 mM ZnO for 24 h) than the similarly treated but more robust nasal (~74%), buccal (~73%), and alveolar (~82%) cell-based models.
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The role of PGE2 and EP receptors on lung's immune and structural cells; possibilities for future asthma therapy. Pharmacol Ther 2023; 241:108313. [PMID: 36427569 DOI: 10.1016/j.pharmthera.2022.108313] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 10/06/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Asthma is the most common airway chronic disease with treatments aimed mainly to control the symptoms. Adrenergic receptor agonists, corticosteroids and anti-leukotrienes have been used for decades, and the development of more targeted asthma treatments, known as biological therapies, were only recently established. However, due to the complexity of asthma and the limited efficacy as well as the side effects of available treatments, there is an urgent need for a new generation of asthma therapies. The anti-inflammatory and bronchodilatory effects of prostaglandin E2 in asthma are promising, yet complicated by undesirable side effects, such as cough and airway irritation. In this review, we summarize the most important literature on the role of all four E prostanoid (EP) receptors on the lung's immune and structural cells to further dissect the relevance of EP2/EP4 receptors as potential targets for future asthma therapy.
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Shaughnessy CA, Yadav S, Bratcher PE, Zeitlin PL. Receptor-mediated activation of CFTR via prostaglandin signaling pathways in the airway. Am J Physiol Lung Cell Mol Physiol 2022; 322:L305-L314. [PMID: 35020527 PMCID: PMC8858663 DOI: 10.1152/ajplung.00388.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Cystic fibrosis (CF) is a genetic disease caused by mutations of the gene encoding a cAMP-activated Cl- channel, the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR modulator therapies consist of small-molecule drugs that rescue mutant CFTR. Regimens of single or combinations of CFTR modulators still rely on endogenous levels of cAMP to regulate CFTR activity. We investigated CFTR activation by the natural mediator prostaglandin E2 (PGE2) and lubiprostone (a Food and Drug Administration-approved drug known to target prostaglandin receptors) and tested the hypothesis that receptor-mediated CFTR activators can be used in combination with currently available CFTR modulators to increase function of mutant CFTR. Primary-cultured airway epithelia were assayed in Ussing chambers. Experimental CFTR activators and established CFTR modulators were applied for 24 h and/or acutely and analyzed for their effect on CFTR activity as measured by changes in short-circuit current (ISC). In non-CF airway epithelia, acute application of lubiprostone and PGE2 activated CFTR to the levels comparable to forskolin (Fsk). Pretreatment (24 h) with antagonists to prostaglandin receptors EP2 and EP4 abolished the ability of lubiprostone to acutely activate CFTR. In F508del homozygous airway epithelia pretreated with the triple combination of elexacaftor, tezacaftor, and ivacaftor (ELEXA/TEZ/IVA; i.e., Trikafta), acute application of lubiprostone was able to maximally activate CFTR. Prolonged (24 h) cotreatment of F508del homozygous epithelia with ELEXA/TEZ/IVA and lubiprostone increased acute CFTR activation by ∼60% compared with the treatment with ELEXA/TEZ/IVA alone. This work establishes the feasibility of targeting prostaglandin receptors to activate CFTR on the airway epithelia and demonstrates that cotreatment with lubiprostone can further restore modulator-rescued CFTR.
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Affiliation(s)
| | - Sangya Yadav
- 1Department of Pediatrics, National Jewish Health, Denver, Colorado
| | - Preston E. Bratcher
- 1Department of Pediatrics, National Jewish Health, Denver, Colorado,2Department of Pediatrics, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
| | - Pamela L. Zeitlin
- 1Department of Pediatrics, National Jewish Health, Denver, Colorado,2Department of Pediatrics, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado
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Moving forward with isoprostanes, neuroprostanes and phytoprostanes: where are we now? Essays Biochem 2021; 64:463-484. [PMID: 32602531 DOI: 10.1042/ebc20190096] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 02/06/2023]
Abstract
Polyunsaturated fatty acids (PUFAs) are essential components in eukaryotic cell membrane. They take part in the regulation of cell signalling pathways and act as precursors in inflammatory metabolism. Beside these, PUFAs auto-oxidize through free radical initiated mechanism and release key products that have various physiological functions. These products surfaced in the early nineties and were classified as prostaglandin isomers or isoprostanes, neuroprostanes and phytoprostanes. Although these molecules are considered robust biomarkers of oxidative damage in diseases, they also contain biological activities in humans. Conceptual progress in the last 3 years has added more understanding about the importance of these molecules in different fields. In this chapter, a brief overview of the past 30 years and the recent scope of these molecules, including their biological activities, biosynthetic pathways and analytical approaches are discussed.
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Joshi R, Hamed O, Yan D, Michi AN, Mostafa MM, Wiehler S, Newton R, Giembycz MA. Prostanoid Receptors of the EP 4-Subtype Mediate Gene Expression Changes in Human Airway Epithelial Cells with Potential Anti-Inflammatory Activity. J Pharmacol Exp Ther 2020; 376:161-180. [PMID: 33158942 DOI: 10.1124/jpet.120.000196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/03/2020] [Indexed: 11/22/2022] Open
Abstract
There is a clear, unmet clinical need to identify new drugs to treat individuals with asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF) in whom current medications are either inactive or suboptimal. In preclinical models, EP4-receptor agonists display efficacy, but their mechanism of action is unclear. In this study, using human bronchial epithelial cells as a therapeutically relevant drug target, we hypothesized that changes in gene expression may play an important role. Several prostanoid receptor mRNAs were detected in BEAS-2B cells, human primary bronchial epithelial cells (HBECs) grown in submersion culture and HBECs grown at an air-liquid interface with PTGER4 predominating. By using the activation of a cAMP response element reporter in BEAS-2B cells as a surrogate of gene expression, Schild analysis determined that PTGER4 mRNAs encoded functional EP4-receptors. Moreover, inhibitors of phosphodiesterase 4 (roflumilast N-oxide [RNO]) and cAMP-dependent protein kinase augmented and attenuated, respectively, reporter activation induced by 2-[3-[(1R,2S,3R)-3-hydroxy-2-[(E,3S)-3-hydroxy-5-[2-(methoxymethyl)phenyl]pent-1-enyl]-5-oxo-cyclopentyl]sulphanylpropylsulphanyl] acetic acid (ONO-AE1-329), a selective EP4-receptor agonist. ONO-AE1-329 also enhanced dexamethasone-induced activation of a glucocorticoid response element reporter in BEAS-2B cells, which was similarly potentiated by RNO. In each airway epithelial cell variant, numerous genes that may impart therapeutic benefit in asthma, COPD, and/or IPF were differentially expressed by ONO-AE1-329, and those changes were often augmented by RNO and/or dexamethasone. We submit that an EP4-receptor agonist, either alone or as a combination therapy, may be beneficial in individuals with chronic lung diseases in whom current treatment options are inadequate. SIGNIFICANCE STATEMENT: Using human bronchial epithelial cells as a therapeutically relevant drug target, we report that EP4-receptor activation promoted gene expression changes that could provide therapeutic benefit in individuals with asthma, COPD, and IPF in whom current treatment options are ineffective or suboptimal.
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Affiliation(s)
- Radhika Joshi
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Omar Hamed
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Dong Yan
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Aubrey N Michi
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mahmoud M Mostafa
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Shahina Wiehler
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Scholte BJ, Horati H, Veltman M, Vreeken RJ, Garratt LW, Tiddens HAWM, Janssens HM, Stick SM. Oxidative stress and abnormal bioactive lipids in early cystic fibrosis lung disease. J Cyst Fibros 2019; 18:781-789. [PMID: 31031161 DOI: 10.1016/j.jcf.2019.04.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/10/2019] [Accepted: 04/12/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Clinical data indicate that airway inflammation in children with cystic fibrosis (CF) arises early, is associated with structural lung damage, and predicts progression. In bronchoalveolar lavage fluid (BALF) from CFTR mutant mice, several aspects of lipid metabolism are abnormal that contributes to lung disease. We aimed to determine whether lipid pathway dysregulation is also observed in BALF from children with CF, to identify biomarkers of early lung disease and potential therapeutic targets. METHODS A comprehensive panel of lipids that included Sphingolipids, oxylipins, isoprostanes and lysolipids, all bioactive lipid species known to be involved in inflammation and tissue remodeling, were measured in BALF from children with CF (1-6 years, N = 33) and age-matched non-CF patients with unexplained inflammatory disease (N = 16) by HPLC-MS/MS. Lipid data were correlated with chest CT scores and BALF inflammation biomarkers. RESULTS The ratio of long chain to very long chain ceramide species (LCC/VLCC) and lysolipid levels were enhanced in CF compared to non-CF patients, despite comparable neutrophil counts and bacterial load. In CF patients both LCC/VLCC and lysolipid levels correlated with inflammation and chest CT scores. The ceramide precursors Sphingosine, Sphinganine, Sphingomyelin, correlated with inflammation, whilst the oxidative stress marker isoprostane correlated with inflammation and chest CT scores. No correlation between lipids and current bacterial infection in CF (N = 5) was observed. CONCLUSIONS Several lipid biomarkers of early CF lung disease were identified, which point toward potential disease monitoring and therapeutic approaches that can be used to complement CFTR modulators.
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Affiliation(s)
- Bob J Scholte
- Erasmus MC, Rotterdam, the Netherlands, Cell Biology; Erasmus MC, Sophia Children Hospital, Pediatric Pulmonology, the Netherlands.
| | - Hamed Horati
- Erasmus MC, Sophia Children Hospital, Pediatric Pulmonology, the Netherlands
| | - Mieke Veltman
- Erasmus MC, Rotterdam, the Netherlands, Cell Biology; Erasmus MC, Sophia Children Hospital, Pediatric Pulmonology, the Netherlands
| | - Rob J Vreeken
- Netherlands Metabolomics Centre, LACDR, Leiden, the Netherlands
| | - Luke W Garratt
- Telethon Kids Institute, University of Western Australia, Subiaco, 6008, Western Australia, Australia
| | - Harm A W M Tiddens
- Erasmus MC, Sophia Children Hospital, Pediatric Pulmonology, the Netherlands
| | - Hettie M Janssens
- Erasmus MC, Sophia Children Hospital, Pediatric Pulmonology, the Netherlands
| | - Stephen M Stick
- Telethon Kids Institute, University of Western Australia, Subiaco, 6008, Western Australia, Australia; Division of Paediatrics and Child Health, University of Western Australia, Nedlands, 6009, Western Australia, Australia; Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Nedlands, 6009, Western Australia, Australia; Centre for Cell Therapy and Regenerative Medicine, School of Medicine and Pharmacology, University of Western Australia, Nedlands, 6009, Western Australia, Australia
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Sellers ZM, Illek B, Figueira MF, Hari G, Joo NS, Sibley E, Souza-Menezes J, Morales MM, Fischer H, Wine JJ. Impaired PGE2-stimulated Cl- and HCO3- secretion contributes to cystic fibrosis airway disease. PLoS One 2017; 12:e0189894. [PMID: 29281691 PMCID: PMC5744969 DOI: 10.1371/journal.pone.0189894] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 12/04/2017] [Indexed: 12/15/2022] Open
Abstract
Background Airway mucociliary clearance (MCC) is an important defense mechanism against pulmonary infections and is compromised in cystic fibrosis (CF). Cl- and HCO3- epithelial transport are integral to MCC. During pulmonary infections prostaglandin E2 (PGE2) production is abundant. Aim To determine the effect of PGE2 on airway Cl- and HCO3- secretion and MCC in normal and CF airways. Methods We examined PGE2 stimulated MCC, Cl- and HCO3- secretion using ferret trachea, human bronchial epithelial cell cultures (CFBE41o- with wildtype CFTR (CFBE41 WT) or homozygous F508del CFTR (CFBE41 CF) and human normal bronchial submucosal gland cell line (Calu-3) in Ussing chambers with or without pH-stat. Results PGE2 stimulated MCC in a dose-dependent manner and was partially impaired by CFTRinh-172. PGE2-stimulated Cl- current in ferret trachea was partially inhibited by CFTRinh-172, with niflumic acid eliminating the residual current. CFBE41 WT cell monolayers produced a robust Cl- and HCO3- secretory response to PGE2, both of which were completely inhibited by CFTRinh-172. CFBE41 CF cells exhibited no response to PGE2. In Calu-3 cells, PGE2 stimulated Cl- and HCO3- secretion. Cl- secretion was partially inhibited by CFTRinh-172, with additional inhibition by niflumic acid. HCO3- secretion was completely inhibited by CFTRinh-172. Conclusions PGE2 stimulates bronchotracheal MCC and this response is decreased in CF. In CF airway, PGE2-stimulated Cl- and HCO3- conductance is impaired and may contribute to decreased MCC. There remains a CFTR-independent Cl- current in submucosal glands, which if exploited, could represent a means of improving airway Cl- secretion and MCC in CF.
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Affiliation(s)
- Zachary M. Sellers
- Division of Pediatric Gastroenterology, Hepatolfifogy, and Nutrition, Stanford University, Palo Alto, CA, United States of America
- Cystic Fibrosis Research Laboratory, Stanford University, Palo Alto, CA, United States of America
- * E-mail:
| | - Beate Illek
- Children’s Hospital Oakland Research Institute, Oakland, CA, United States of America
| | - Miriam Frankenthal Figueira
- Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Core for Ecology and Socio Environmental Development, Federal University of Rio de Janeiro, Macaé, RJ, Brazil
| | - Gopika Hari
- Children’s Hospital Oakland Research Institute, Oakland, CA, United States of America
| | - Nam Soo Joo
- Cystic Fibrosis Research Laboratory, Stanford University, Palo Alto, CA, United States of America
| | - Eric Sibley
- Division of Pediatric Gastroenterology, Hepatolfifogy, and Nutrition, Stanford University, Palo Alto, CA, United States of America
| | - Jackson Souza-Menezes
- Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Core for Ecology and Socio Environmental Development, Federal University of Rio de Janeiro, Macaé, RJ, Brazil
| | - Marcelo M. Morales
- Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Horst Fischer
- Children’s Hospital Oakland Research Institute, Oakland, CA, United States of America
| | - Jeffrey J. Wine
- Cystic Fibrosis Research Laboratory, Stanford University, Palo Alto, CA, United States of America
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Activating prostaglandin E2 receptor subtype EP4 increases secreted mucin from airway goblet cells. Pulm Pharmacol Ther 2017; 48:117-123. [PMID: 29129801 DOI: 10.1016/j.pupt.2017.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 10/03/2017] [Accepted: 11/07/2017] [Indexed: 01/24/2023]
Abstract
Prostaglandin E2 (PGE2) is a ligand of the E-type prostanoid receptors, EP1-4. PGE2 secretion is increased in the airways of patients with asthma by secretory phospholipases A2, which also increases MUC5AC mucin in goblet cells. We hypothesized that PGE2 would also increase MUC5AC mRNA and secreted protein through specific EP receptor activation. We sought to assess the effect of specific EP receptor activation on MUC5AC secretion from ciliated-enriched cells or goblet-enriched cells induced by IL-13. We develop an enriched goblet cell epithelium by growing normal human bronchial epithelial cells at air liquid interface for 14 days in the presence of IL-13. We examined exposure to 4 specific EP receptor agonists at 24 h and 14 days in cells grown with or without IL-13 exposure, and measured MUC5AC mRNA and secreted protein, as well as airway culture morphology, and EP receptor expression. In ciliated-enriched cells grown in the absence of IL-13, the EP4 receptor agonist modestly increased both MUC5AC mRNA and secretion (p < 0.001, 241% increase of transcripts and p < 0.01, 86% increase of secreted protein) but did not visibly change cell morphology. In goblet-enriched cells grown in the presence of IL-13, the EP4 receptor agonist greatly increased both MUC5AC mRNA and protein (p < 0.001, 315% increase of transcripts and 92% increase of secreted protein). Specific activation of the other EP receptor had no effect on secreted mucin. EP4 receptor mRNA and protein were significantly increased in goblet-enriched cells, while the other receptor mRNA were decreased. We conclude that PGE2 stimulates airway mucin production predominantly by EP4 receptor activation in association with increased EP4 receptor expression. This may contribute to mucus hypersecretion as seen in severe asthma.
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Galano JM, Lee YY, Oger C, Vigor C, Vercauteren J, Durand T, Giera M, Lee JCY. Isoprostanes, neuroprostanes and phytoprostanes: An overview of 25years of research in chemistry and biology. Prog Lipid Res 2017; 68:83-108. [PMID: 28923590 DOI: 10.1016/j.plipres.2017.09.004] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 09/14/2017] [Accepted: 09/14/2017] [Indexed: 02/07/2023]
Abstract
Since the beginning of the 1990's diverse types of metabolites originating from polyunsaturated fatty acids, formed under autooxidative conditions were discovered. Known as prostaglandin isomers (or isoprostanoids) originating from arachidonic acid, neuroprostanes from docosahexaenoic acid, and phytoprostanes from α-linolenic acid proved to be prevalent in biology. The syntheses of these compounds by organic chemists and the development of sophisticated mass spectrometry methods has boosted our understanding of the isoprostanoid biology. In recent years, it has become accepted that these molecules not only serve as markers of oxidative damage but also exhibit a wide range of bioactivities. In addition, isoprostanoids have emerged as indicators of oxidative stress in humans and their environment. This review explores in detail the isoprostanoid chemistry and biology that has been achieved in the past three decades.
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Affiliation(s)
- Jean-Marie Galano
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Université de Montpellier, France
| | - Yiu Yiu Lee
- School of Biological Sciences, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Camille Oger
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Université de Montpellier, France
| | - Claire Vigor
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Université de Montpellier, France
| | - Joseph Vercauteren
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Université de Montpellier, France
| | - Thierry Durand
- Institut des Biomolécules Max Mousseron, UMR 5247 CNRS, ENSCM, Université de Montpellier, France
| | - Martin Giera
- Leiden University Medical Center, Center for Proteomics and Metabolomics, Albinusdreef 2, 2300RC Leiden, The Netherlands
| | - Jetty Chung-Yung Lee
- School of Biological Sciences, The University of Hong Kong, Hong Kong Special Administrative Region.
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Ivonnet P, Unwalla H, Salathe M, Conner GE. Soluble adenylyl cyclase mediates hydrogen peroxide-induced changes in epithelial barrier function. Respir Res 2016; 17:15. [PMID: 26857816 PMCID: PMC4746823 DOI: 10.1186/s12931-016-0329-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 01/26/2016] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Elevated H2O2 levels are associated with inflammatory diseases and H2O2 exposure is known to disrupt epithelial barrier function, leading to increased permeability and decreased electrical resistance. In normal human bronchial epithelial (NHBE) cells, fully differentiated at the air liquid interface (ALI), H2O2 activates an autocrine prostaglandin pathway that stimulates transmembrane adenylyl cyclase (tmAC) as well as soluble adenylyl cyclase (sAC), but the role of this autocrine pathway in H2O2-mediated barrier disruption is not entirely clear. METHODS To further characterize the mechanism of H2O2-induced barrier disruption, NHBE cultures were treated with H2O2 and evaluated for changes in transepithelial resistance and mannitol permeability using agonist and inhibitors to dissect the pathway. RESULTS A short (<10 min) H2O2 treatment was sufficient to induce resistance and permeability changes that occurred 40 min to 1 h later and the changes were partially sensitive to EP1 but not EP4 receptor antagonists. EP1 receptors were localized to the apical compartment of NHBE. Resistance and permeability changes were sensitive to inhibition of sAC but not tmAC and were partially blocked by PKA inhibition. Pretreatment with a PLC inhibitor or an IP3 receptor antagonist reduced changes in resistance and permeability suggesting activation of sAC occurred through increased intracellular calcium. CONCLUSION The data support an important role for prostaglandin activation of sAC and PKA in H2O2-induced barrier disruption.
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Affiliation(s)
- Pedro Ivonnet
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Miller School of Medicine, University of Miami, 1600 NW 10th Ave, Miami, 33136, FL, USA.
| | - Hoshang Unwalla
- Department of Immunology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL, 33199, USA.
| | - Matthias Salathe
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Miller School of Medicine, University of Miami, 1600 NW 10th Ave, Miami, 33136, FL, USA.
| | - Gregory E Conner
- Department of Cell Biology, Miller School of Medicine, University of Miami, 1600 NW 10th Ave, Miami, 33136, FL, USA.
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Mastalerz L, Januszek R, Kaszuba M, Wójcik K, Celejewska-Wójcik N, Gielicz A, Plutecka H, Oleś K, Stręk P, Sanak M. Aspirin provocation increases 8-iso-PGE2 in exhaled breath condensate of aspirin-hypersensitive asthmatics. Prostaglandins Other Lipid Mediat 2015. [PMID: 26209241 DOI: 10.1016/j.prostaglandins.2015.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Isoprostanes are bioactive compounds formed by non-enzymatic oxidation of polyunsaturated fatty acids, mostly arachidonic, and markers of free radical generation during inflammation. In aspirin exacerbated respiratory disease (AERD), asthmatic symptoms are precipitated by ingestion of non-steroid anti-inflammatory drugs capable for pharmacologic inhibition of cyclooxygenase-1 isoenzyme. We investigated whether aspirin-provoked bronchoconstriction is accompanied by changes of isoprostanes in exhaled breath condensate (EBC). METHODS EBC was collected from 28 AERD subjects and 25 aspirin-tolerant asthmatics before and after inhalatory aspirin challenge. Concentrations of 8-iso-PGF2α, 8-iso-PGE2, and prostaglandin E2 were measured using gas chromatography/mass spectrometry. Leukotriene E4 was measured by immunoassay in urine samples collected before and after the challenge. RESULTS Before the challenge, exhaled 8-iso-PGF2α, 8-iso-PGE2, and PGE2 levels did not differ between the study groups. 8-iso-PGE2 level increased in AERD group only (p=0.014) as a result of the aspirin challenge. Urinary LTE4 was elevated in AERD, both in baseline and post-challenge samples. Post-challenge airways 8-iso-PGE2 correlated positively with urinary LTE4 level (p=0.046), whereas it correlated negatively with the provocative dose of aspirin (p=0.027). CONCLUSION A significant increase of exhaled 8-iso-PGE2 after inhalatory challenge with aspirin was selective and not present for the other isoprostane measured. This is a novel finding in AERD, suggesting that inhibition of cyclooxygenase may elicit 8-iso-PGE2 production in a specific mechanism, contributing to bronchoconstriction and systemic overproduction of cysteinyl leukotrienes.
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Affiliation(s)
- Lucyna Mastalerz
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Rafał Januszek
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Marek Kaszuba
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Krzysztof Wójcik
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Natalia Celejewska-Wójcik
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Anna Gielicz
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Hanna Plutecka
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland
| | - Krzysztof Oleś
- Department of Otolaryngology, Jagiellonian University School of Medicine, Śniadeckich 2, 31-531 Kraków, Poland
| | - Paweł Stręk
- Department of Otolaryngology, Jagiellonian University School of Medicine, Śniadeckich 2, 31-531 Kraków, Poland
| | - Marek Sanak
- Department of Medicine, Jagiellonian University School of Medicine, Skawińska 8, 31-066 Kraków, Poland.
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12
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Milne GL, Dai Q, Roberts LJ. The isoprostanes--25 years later. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1851:433-45. [PMID: 25449649 PMCID: PMC5404383 DOI: 10.1016/j.bbalip.2014.10.007] [Citation(s) in RCA: 226] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 10/13/2014] [Accepted: 10/21/2014] [Indexed: 01/26/2023]
Abstract
Isoprostanes (IsoPs) are prostaglandin-like molecules generated independent of the cyclooxygenase (COX) by the free radical-induced peroxidation of arachidonic acid. The first isoprostane species discovered were isomeric to prostaglandin F2α and were thus termed F2-IsoPs. Since the initial discovery of the F2-IsoPs, IsoPs with differing ring structures have been identified as well as IsoPs from different polyunsaturated fatty acids, including eicosapentaenoic acid and docosahexanenoic acid. The discovery of these molecules in vivo in humans has been a major contribution to the field of lipid oxidation and free radical research over the course of the past 25 years. These molecules have been determined to be both biomarkers and mediators of oxidative stress in numerous disease settings. This review focuses on recent developments in the field with an emphasis on clinical research. Special focus is given to the use of IsoPs as biomarkers in obesity, ischemia-reperfusion injury, the central nervous system, cancer, and genetic disorders. Additionally, attention is paid to diet and lifestyle factors that can affect endogenous levels of IsoPs. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance."
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Affiliation(s)
- Ginger L Milne
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Qi Dai
- Division of Epidemiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - L Jackson Roberts
- Division of Clinical Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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13
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Ivonnet P, Salathe M, Conner GE. Hydrogen peroxide stimulation of CFTR reveals an Epac-mediated, soluble AC-dependent cAMP amplification pathway common to GPCR signalling. Br J Pharmacol 2014; 172:173-84. [PMID: 25220136 DOI: 10.1111/bph.12934] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 08/27/2014] [Accepted: 09/03/2014] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE H2 O2 is widely understood to regulate intracellular signalling. In airway epithelia, H2 O2 stimulates anion secretion primarily by activating an autocrine PGE2 signalling pathway via EP4 and EP1 receptors to initiate cytic fibrosis transmembrane regulator (CFTR)-mediated Cl(-) secretion. This study investigated signalling downstream of the receptors activated by H2 O2 . EXPERIMENTAL APPROACH Anion secretion by differentiated bronchial epithelial cells was measured in Ussing chambers during stimulation with H2 O2 , an EP4 receptor agonist or β2 -adrenoceptor agonist in the presence and absence of inhibitors of ACs and downstream effectors. Intracellular calcium ([Ca(2+) ]I ) changes were followed by microscopy using fura-2-loaded cells and PKA activation followed by FRET microscopy. KEY RESULTS Transmembrane adenylyl cyclase (tmAC) and soluble AC (sAC) were both necessary for H2 O2 and EP4 receptor-mediated CFTR activation in bronchial epithelia. H2 O2 and EP4 receptor agonist stimulated tmAC to increase exchange protein activated by cAMP (Epac) activity that drives PLC activation to raise [Ca(2+) ]i via Ca(2+) store release (and not entry). Increased [Ca(2+) ]i led to sAC activation and further increases in CFTR activity. Stimulation of sAC did not depend on changes in [HCO3 (-) ]. Ca(2+) -activated apical KCa 1.1 channels and cAMP-activated basolateral KV 7.1 channels contributed to H2 O2 -stimulated anion currents. A similar Epac-mediated pathway was seen following β2 -adrenoceptor or forskolin stimulation. CONCLUSIONS AND IMPLICATIONS H2 O2 initiated a complex signalling cascade that used direct stimulation of tmACs by Gαs followed by Epac-mediated Ca(2+) crosstalk to activate sAC. The Epac-mediated Ca(2+) signal constituted a positive feedback loop that amplified CFTR anion secretion following stimulation of tmAC by a variety of stimuli.
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Affiliation(s)
- P Ivonnet
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, University of Miami, Miami, Florida, USA
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14
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Ziady AG, Hansen J. Redox balance in cystic fibrosis. Int J Biochem Cell Biol 2014; 52:113-23. [PMID: 24657650 DOI: 10.1016/j.biocel.2014.03.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 02/28/2014] [Accepted: 03/11/2014] [Indexed: 11/30/2022]
Abstract
The homeostatic balance between oxidants and antioxidants in biological systems is known as redox balance, and is regulated by complex processes. Redox balance regulates many of the known cellular pathways and disease processes. The dysregulation of redox balance can lead to acute or long-term oxidative or reductive stresses that are associated with many of the abnormalities observed in cystic fibrosis (CF). Over the past 5 decades researchers have examined contributors to redox dysregulation, their molecular products, and their impact on ion transport, cell proliferation, inflammation, bacterial killing, and the metabolism of nucleic acids, proteins, and lipids in CF. CF patients exhibit elevated markers of oxidative stress when compared to non-CF healthy controls; however, whether the reported redox imbalance is sufficient to produce pathology has been controversial. In addition, comparisons between CF and non-CF disease controls have been lacking. To better understand the mechanisms which mediate the generation of oxidants and antioxidants in CF and the importance of their balance in effecting oxidative or reductive stress, we will review the determinants of redox balance in the blood, lumen, and cellular compartments. From the perspective of methodological application, we will focus on the approaches most often used to study oxidant and antioxidants in CF, including biochemical, proteomic, metabolomic, and lipidomic studies, with a discussion of the few transcriptomic analyses that predict changes in the expression of regulators of redox. Finally, we will discuss the utility of oxidants and antioxidants as biomarkers of disease and the use of antioxidant therapy in CF.
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Affiliation(s)
- Assem G Ziady
- Department of Pediatrics, Emory University, Atlanta, GA 30322, USA; Children's Healthcare of Atlanta, Atlanta, GA, USA.
| | - Jason Hansen
- Department of Pediatrics, Emory University, Atlanta, GA 30322, USA
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15
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Conner GE, Ivonnet P, Gelin M, Whitney P, Salathe M. H2O2 stimulates cystic fibrosis transmembrane conductance regulator through an autocrine prostaglandin pathway, using multidrug-resistant protein-4. Am J Respir Cell Mol Biol 2014; 49:672-9. [PMID: 23742099 DOI: 10.1165/rcmb.2013-0156oc] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) activity is essential for the maintenance of airway surface liquid depth, and therefore mucociliary clearance. Reactive oxygen species, increased during inflammatory airway diseases, alter CFTR activity. Here, H2O2 levels in the surface liquid of normal human bronchial epithelial cultures differentiated at the air-liquid interface were estimated, and H2O2-mediated changes in CFTR activity were examined. In Ussing chambers, H2O2-induced anion currents were sensitive to the CFTR inhibitors CFTRinh172 and GlyH-101. These currents were absent in cells from patients with cystic fibrosis. Responses to greater than 500 μM H2O2 were transient. Cyclooxygenase inhibitors blocked the H2O2 response, as did EP1 and EP4 receptor antagonists. A multidrug-resistant protein (MRP) inhibitor and short hairpin RNA directed against MRP4 blocked H2O2 responses. EP1 and EP4 agonists mimicked H2O2 in both control and MRP4 knockdown cells. Thus, H2O2 activates the synthesis, export, and binding of prostanoids via EP4 and, interestingly, EP1 receptors in normal, differentiated human airway epithelial cells to activate cyclic adenosine monophosphate pathways that in turn activate CFTR channels in the apical membrane.
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Affiliation(s)
- Gregory E Conner
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, and
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16
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Konya V, Marsche G, Schuligoi R, Heinemann A. E-type prostanoid receptor 4 (EP4) in disease and therapy. Pharmacol Ther 2013; 138:485-502. [PMID: 23523686 PMCID: PMC3661976 DOI: 10.1016/j.pharmthera.2013.03.006] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 03/07/2013] [Indexed: 01/06/2023]
Abstract
The large variety of biological functions governed by prostaglandin (PG) E2 is mediated by signaling through four distinct E-type prostanoid (EP) receptors. The availability of mouse strains with genetic ablation of each EP receptor subtype and the development of selective EP agonists and antagonists have tremendously advanced our understanding of PGE2 as a physiologically and clinically relevant mediator. Moreover, studies using disease models revealed numerous conditions in which distinct EP receptors might be exploited therapeutically. In this context, the EP4 receptor is currently emerging as most versatile and promising among PGE2 receptors. Anti-inflammatory, anti-thrombotic and vasoprotective effects have been proposed for the EP4 receptor, along with its recently described unfavorable tumor-promoting and pro-angiogenic roles. A possible explanation for the diverse biological functions of EP4 might be the multiple signaling pathways switched on upon EP4 activation. The present review attempts to summarize the EP4 receptor-triggered signaling modules and the possible therapeutic applications of EP4-selective agonists and antagonists.
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Key Words
- ampk, amp-activated protein kinase
- camp, cyclic adenylyl monophosphate
- cftr, cystic fibrosis transmembrane conductance regulator
- clc, chloride channel
- cox, cyclooxygenase
- creb, camp-response element-binding protein
- dp, d-type prostanoid receptor
- dss, dextran sodium sulfate
- egfr, epidermal growth factor receptor
- enos, endothelial nitric oxide synthase
- ep, e-type prostanoid receptor
- epac, exchange protein activated by camp
- eprap, ep4 receptor-associated protein
- erk, extracellular signal-regulated kinase
- fem1a, feminization 1 homolog a
- fp, f-type prostanoid receptor
- grk, g protein-coupled receptor kinase
- 5-hete, 5-hydroxyeicosatetraenoic acid
- icer, inducible camp early repressor
- icam-1, intercellular adhesion molecule-1
- ig, immunoglobulin
- il, interleukin
- ifn, interferon
- ip, i-type prostanoid receptor
- lps, lipopolysaccharide
- map, mitogen-activated protein kinase
- mcp, monocyte chemoattractant protein
- mek, map kinase kinase
- nf-κb, nuclear factor kappa-light-chain-enhancer of activated b cells
- nsaid, non-steroidal anti-inflammatory drug
- pg, prostaglandin
- pi3k, phosphatidyl insositol 3-kinase
- pk, protein kinase
- tp, t-type prostanoid receptor
- tx, thromboxane receptor
- prostaglandins
- inflammation
- vascular disease
- cancerogenesis
- renal function
- osteoporosis
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Affiliation(s)
| | | | | | - Akos Heinemann
- Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Austria
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17
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Jones CL, Li T, Cowley EA. The prostaglandin E₂ type 4 receptor participates in the response to acute oxidant stress in airway epithelial cells. J Pharmacol Exp Ther 2012; 341:552-63. [PMID: 22362924 DOI: 10.1124/jpet.111.187138] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Oxidative stress is implicated in the pathogenesis of many inflammatory pulmonary diseases, including cystic fibrosis (CF). Delineating how oxidative stress stimulates CF transmembrane conductance regulator (CFTR) in airway epithelial cells is useful, both to increase the understanding of airways host defense and suggest therapeutic approaches to reduce the oxidant stress burden in the CF lung. Using the airway epithelial cell line Calu-3, we investigated the hypothesis that hydrogen peroxide (H₂O₂), which stimulates anion efflux through CFTR, does so via the production of prostaglandin E₂ (PGE₂). Using iodide efflux as a biochemical marker of CFTR activity and short circuit current (I(sc)) recordings, we found that the H₂O₂-stimulated efflux was abolished by cyclooxygenase-1 inhibition and potentially also involves microsomal prostaglandin E synthase-1 activity, implicating a role for PGE₂ production. Furthermore, H₂O₂ application resulted in a rapid release of PGE₂ from Calu-3 cells. We additionally hypothesized that the PGE₂ subtype 4 (EP(4)) receptor was involved in mediating this response. In the presence of (4Z)-7-[(rel-1S,2S,5R)-5-((1,1'-biphenyl-4-yl)methoxy)-2-(4-morpholinyl)-3-oxocyclopentyl]-4-heptenoic acid (AH23848) (which blocks the EP₄ receptor), the H₂O₂-stimulated response was abolished. To investigate this finding in a polarized system, we measured the increase in I(sc) induced by H₂O₂ addition in the presence and absence of AH23848. H₂O₂ induced a robust increase in I(sc), which was significantly attenuated in the presence of AH23848, suggesting some role for the EP₄ receptor. In conclusion, with H₂O₂ as a model oxidant stress, stimulation of CFTR seems to involve PGE₂ production and likely EP₄ receptor activation in Calu-3 airway epithelial cells. This mechanism would be compromised in the CF airways.
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Affiliation(s)
- Christina L Jones
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
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18
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Jamil J, Wright A, Harrison N, Kegey E, Flowers AF, Flyod NJ, Kotera C, Guy A, Galano JM, Durand T, Njie-Mbye YF, Ohia SE, Opere CA. Regulation of [³H]d-aspartate release by the 5-F(2t)-isoprostane and its 5-epimer in isolated bovine retina. Neurochem Res 2011; 37:574-82. [PMID: 22081406 DOI: 10.1007/s11064-011-0645-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 10/25/2011] [Accepted: 11/02/2011] [Indexed: 11/25/2022]
Abstract
We have evidence that 15-F₂-isoprostanes (15-F₂-IsoPs) regulate excitatory neurotransmitter release in ocular tissues. Although 5-F₂-IsoPs are abundantly produced in mammals, their pharmacological actions on neurotransmitter release remain unknown. In the present study, we compared the effect of the 5-F₂-IsoP epimer pair, 5-F(2t)-IsoP (C5-OH in β-position) and 5-epi-5-F(2t)-IsoP (C5-OH in α-position), on K⁺-evoked [³H]D-aspartate release in isolated bovine retina. We further examined the role of prostanoid receptors on the inhibitory action of 5-epi-5-F(2t)-IsoP on [³H]D-aspartate overflow. Isolated bovine retina were prepared for studies of K⁺-evoked release of [³H]D-aspartate using the superfusion method. 5-epi-5-F(2t)-IsoP (0.01 nM to 1 μM), attenuated K⁺-evoked [³H]D-aspartate release in a concentration-dependent manner, with the inhibitory effect of 26.9% (P < 0.001; IC₂₅ = 0.2 μM) being achieved at 1 μM concentration. Its 5-(S)-OH-epimer, 5-F(2t)-IsoP (0.1 nM-1 μM), exhibited an inhibitory biphasic action, yielding a maximal response of 35.7% (P < 0.001) at 10 nM concentration of the drug (IC₂₅ value of 3 nM). Although the prostanoid-receptor antagonists, AH 6809 (10 μM; EP₁₋₃/DP) and BAY-u3405 (10 μM; DP/Tx) exhibited no effect on 5-epi-5-F(2t)-IsoP (10 nM-1 μM)-mediated inhibition, SC-19220 (1 μM; EP₁) completely reversed 5-epi-5-F(2t)-IsoP (0.1 μM and 1 μM)-induced attenuation of K⁺-evoked [³H]D-aspartate release. Similarly, both SC-51322 (10 μM; EP₁ and AH 23848 (1 μM; EP₄) reversed the inhibitory action elicited by 5-epi-5-F(2t)-IsoP (0.1 μM) on the neurotransmitter release. We conclude that the 5-F₂-IsoP epimer pair, 5-F(2t)-IsoP and 5-epi-5-F(2t)-IsoP, attenuate K⁺-induced [³H]D-aspartate release in isolated bovine retina presumably via prostanoid receptor dependent mechanisms. The trans-orientation of the allylic hydroxyl group at position C5 accounts for the apparent biphasic response exhibited by 5-F(2t)-IsoP on excitatory neurotransmitter release.
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Affiliation(s)
- Jamal Jamil
- Department of Pharmacy Sciences, School of Pharmacy and Health Professions, Creighton University Medical Center, 2500 California Plaza, Omaha, NE 68178, USA
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19
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Role of prostanoid production and receptors in the regulation of retinal endogenous amino acid neurotransmitters by 8-isoprostaglandin E2, ex vivo. Neurochem Res 2011; 34:2170-80. [PMID: 19513831 DOI: 10.1007/s11064-009-0013-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2009] [Indexed: 12/11/2022]
Abstract
The role of enzymes and receptors of the prostanoid pathway in the inhibitory effect of 8-isoprostaglandin E2 (8-isoPGE2) on endogenous amino acid neurotransmitter levels was examined, ex vivo. Freshly isolated bovine eyeballs were injected intravitreally with IsoPs, incubated in Krebs buffer for 30 min and retina prepared for HPLC-ECD detection of amino acids. 8-isoPGE2 attenuated retinal glutamate and its metabolite, glutamine and glycine in a concentration-dependent manner. The nonselective cyclooxygenase (COX)-inhibitor, flurbiprofen, COX-2 selective inhibitor, NS-398 and thromboxane (Tx) synthase inhibitor, furegrelate had no effect on both basal amino acid levels and the inhibitory effects of 8-isoPGE2 (1-100 μM) on the retinal amino acids. Whereas the TP-receptor antagonist SQ-29548(10 μM) exhibited no effect, SC-19220(EP1; 30 μM), AH-6809(EP(1-3); 30 μM) and AH-23848(EP4; 30 μM) reversed the inhibitory effects of 8-isoPGE2 (0.01-100 μM) on glutamate, glutamine and glycine levels. We conclude that prostanoid EP-receptors regulate the inhibitory effect of 8-isoPGE2 on basal levels of endogenous amino acids in bovine retina, ex vivo.
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20
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Isoprostanes and asthma. Biochim Biophys Acta Gen Subj 2011; 1810:1091-5. [PMID: 21596100 DOI: 10.1016/j.bbagen.2011.04.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/06/2011] [Accepted: 04/28/2011] [Indexed: 12/12/2022]
Abstract
Isoprostanes are prostaglandin (PG)-like compounds generated in vivo following oxidative stress by non-enzymatic peroxidation of polyunsaturated fatty acids, including arachidonic acid. They are named based on their prostane ring structure and by the localization of hydroxyl groups on the carbon side chain; these structural differences result in a broad array of isoprostane molecules with varying biological properties. Generation of specific isoprostanes is also regulated by host cell redox conditions; reducing conditions favor F₂-isoprostane production while under conditions with deficient antioxidant capacity, D₂- and E₂-isoprostanes are formed. F₂-isoprostanes (F₂-isoP) are considered reliable markers of oxidative stress in pulmonary diseases including asthma. Importantly, F₂-isoP and other isoprostanes function as ligands for PG receptors, and potentially other receptors that have not yet been identified. They have been reported to have important biological properties in many organs. In the lung, isoprostanes regulate cellular processes affecting airway smooth muscle tone, neural secretion, epithelial ion flux, endothelial cell adhesion and permeability, and macrophage adhesion and function. In this review, we will summarize the evidence that F₂-isoP functions as a marker of oxidative stress in asthma, and that F₂-isoP and other isoprostanes exert biological effects that contribute to the pathogenesis of asthma. This article is part of a Special Issue entitled Biochemistry of Asthma.
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21
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Li T, Qi J, Cowley EA. Activation of the EP4 prostanoid receptor induces prostaglandin E2 and pro-inflammatory cytokine production in human airway epithelial cells. Pulm Pharmacol Ther 2011; 24:42-8. [DOI: 10.1016/j.pupt.2010.10.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 09/02/2010] [Accepted: 10/13/2010] [Indexed: 11/28/2022]
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22
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Al-Shabrawey M, Smith S. Prediction of diabetic retinopathy: role of oxidative stress and relevance of apoptotic biomarkers. EPMA J 2010; 1:56-72. [PMID: 23199041 PMCID: PMC3405307 DOI: 10.1007/s13167-010-0002-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2009] [Accepted: 01/25/2010] [Indexed: 12/15/2022]
Abstract
Diabetic retinopathy (DR) is the foremost cause of blindness in working-aged worldwide; it is characterized by vascular and neuronal degeneration. Features of DR include leukocyte adhesion, increased vascular permeability, neovascularization and neuronal cell death. Early diagnosis and intervention are important to prevent or at least ameliorate the development of DR. Recent reports indicate that pathophysiological mechanisms leading to diabetic retinopathy include oxidative stress and retinal cell death cascades. Circulating biomarkers of oxidative stress such as malondialdehyde (MDA), thiobarbituric acid reacting substances (TBARS), conjugated diene (CD), advanced oxidation protein products (AOPP), protein carbonyl, 8-hydroxydeoxyguanosin (8-OHdG), nitrotyrosine, and F(2) isoprostanes and pro-apoptosis molecules (caspase-3, Fas, and Bax) are associated with increased susceptibility to develop DR in diabetic subjects. Thus, identification of oxidative stress and cell death biomarkers in diabetic patients could be in favor of predicting, diagnosis, and prevention of DR, and to target for novel therapeutic interventions.
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Affiliation(s)
- Mohamed Al-Shabrawey
- Oral Biology and Anatomy, School of Dentistry, Medical College of Georgia, Augusta, GA 30912 USA
- Ophthalmology and Vision Discovery Institute, Medical College of Georgia, Augusta, GA 30912 USA
- Opthalmology, King Saud University, Riyadh, Saudi Arabia
| | - Sylvia Smith
- Ophthalmology and Vision Discovery Institute, Medical College of Georgia, Augusta, GA 30912 USA
- Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912 USA
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23
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Scheckenbach KEL, Losa D, Dudez T, Bacchetta M, O'Grady S, Crespin S, Chanson M. Prostaglandin E₂regulation of cystic fibrosis transmembrane conductance regulator activity and airway surface liquid volume requires gap junctional communication. Am J Respir Cell Mol Biol 2010; 44:74-82. [PMID: 20167933 DOI: 10.1165/rcmb.2009-0361oc] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Stimulation of the cystic fibrosis transmembrane conductance regulator (CFTR) by protease-activated receptors (PARs) at the basolateral membranes and by adenosine receptors (ADO-Rs) at the apical membrane maintain airway surface liquid (ASL) volume, which is required to ensure hydrated and clearable mucus. Both pathways involve the release of prostaglandin E₂ (PGE₂) and the stimulation of their basolateral receptors (EP-Rs). We sought to determine whether gap junctions contribute to the coordination of these pathways for modulating CFTR activity and mucus hydration. We used RT-PCR and Western blotting to determine connexin (Cx), CD73, and EP-R expression in a Calu-3 airway epithelial cell line grown on Transwell (Corning Costar, Cambridge, MA) inserts. We used dye coupling to evaluate gap junctional intercellular communication (GJIC). We used Ussing chamber studies and X-Z confocal microscopy to monitor Cl(-) secretion and ASL volume regulation. We found that connexin 43 (Cx43)-mediated GJIC was increased either by endogenous ADO after the hydrolysis of purine nucleotides by CD73 or by the direct activation of ADO-Rs. Inhibition of phospholipase A2 and cyclooxygenase prevented ADO-dependent increases in GJIC, suggesting the involvement of PGE₂. PGE₂ was found to increase GJIC markedly by stimulating EP4-Rs. The modulation of ADO signaling also affected the PAR-dependent activation of CFTR. The reduction of GJIC by CD73 or Cx43 inhibition prevented PAR-evoked CFTR currents in Ussing chambers. The inhibition of GJIC resulted in a failure of PGE₂ to increase ASL volume in Calu-3 cells and in primary cultures of well-differentiated human airway epithelial cells. Thus, gap junctions coordinate a signaling network comprising CFTR, ADO-Rs, PARs, and EP-Rs, and are required for ASL volume homeostasis.
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Affiliation(s)
- K E Ludwig Scheckenbach
- Laboratory of Clinical Investigation III, Department of Pediatrics, Geneva University Hospitals, 4 Gabrielle-Perret-Gentil, Geneva 4, Switzerland
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Peters T, Henry PJ. Protease-activated receptors and prostaglandins in inflammatory lung disease. Br J Pharmacol 2009; 158:1017-33. [PMID: 19845685 PMCID: PMC2785524 DOI: 10.1111/j.1476-5381.2009.00449.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 06/11/2009] [Accepted: 07/08/2009] [Indexed: 12/17/2022] Open
Abstract
Protease-activated receptors (PARs) are a novel family of G protein-coupled receptors. Signalling through PARs typically involves the cleavage of an extracellular region of the receptor by endogenous or exogenous proteases, which reveals a tethered ligand sequence capable of auto-activating the receptor. A considerable body of evidence has emerged over the past 20 years supporting a prominent role for PARs in a variety of human physiological and pathophysiological processes, and thus substantial attention has been directed towards developing drug-like molecules that activate or block PARs via non-proteolytic pathways. PARs are widely expressed within the respiratory tract, and their activation appears to exert significant modulatory influences on the level of bronchomotor tone, as well as on the inflammatory processes associated with a range of respiratory tract disorders. Nevertheless, there is debate as to whether the principal response to PAR activation is an augmentation or attenuation of airways inflammation. In this context, an important action of PAR activators may be to promote the generation and release of prostanoids, such as prostglandin E(2), which have well-established anti-inflammatory effects in the lung. In this review, we primarily focus on the relationship between PARs, prostaglandins and inflammatory processes in the lung, and highlight their potential role in selected respiratory tract disorders, including pulmonary fibrosis, asthma and chronic obstructive pulmonary disease.
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Affiliation(s)
- Terence Peters
- School of Medicine and Pharmacology, University of Western Australia, Nedlands, Australia
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25
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Brechbuhl HM, Min E, Kariya C, Frederick B, Raben D, Day BJ. Select cyclopentenone prostaglandins trigger glutathione efflux and the role of ABCG2 transport. Free Radic Biol Med 2009; 47:722-30. [PMID: 19520157 PMCID: PMC2730198 DOI: 10.1016/j.freeradbiomed.2009.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2008] [Revised: 04/24/2009] [Accepted: 06/05/2009] [Indexed: 01/08/2023]
Abstract
Electrophilic cyclopentenone prostaglandins (cyPGs), such as 15-deoxy-Delta(12,14)-prostaglandin J(2) (15dPGJ(2)), initiate redox-based cell signaling responses including increased intracellular glutathione (GSH) synthesis. We investigated whether cyPGs facilitated GSH efflux and if members of the ATP-binding cassette (ABC) protein family mediated the efflux. Four human cell lines were treated with 1-6 microM cyPGs for 48 h. Media and cells were harvested for GSH measurements using HPLC-EC. CyPG treatment increased extracellular GSH levels two- to threefold over controls in HN4 and C38 cells and five- to sixfold in SAEC and MDA 1586 cells and was dependent on increased GSH synthesis. Our studies show that prostaglandin D(2) and its metabolites, prostaglandin J(2) and 15dPGJ(2), specifically induce GSH efflux compared to other eicosanoids. These higher extracellular GSH levels were associated with protection from tert-butylhydroperoxide. Superarray analysis of ABC transporters suggested only ABCG2 expression had a positive relationship in the four cell types compared with extracellular GSH increases after cyPG treatment. The ABCG2 substrate Hoechst 33342 inhibited extracellular GSH increase after 15dPGJ(2) treatment. We report for the first time that ABCG2 may play a role in GSH efflux in response to cyPG treatment and may link inflammatory signaling with antioxidant adaptive responses.
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Affiliation(s)
- Heather M. Brechbuhl
- Department of Pharmaceutical Sciences, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
| | - Elysia Min
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
| | - Chirag Kariya
- Department of Radiation Oncology, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
| | - Barbara Frederick
- Department of Radiation Oncology, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
| | - David Raben
- Department of Radiation Oncology, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
| | - Brian J. Day
- Department of Medicine, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
- Department of Immunology, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
- Department of Pharmaceutical Sciences, University of Colorado Denver Health Sciences Center, Denver, Colorado, USA
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
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Expression and functional evidence of the prostaglandin F2α receptor mediating contraction in human umbilical vein. Eur J Pharmacol 2009; 610:68-74. [DOI: 10.1016/j.ejphar.2009.03.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Revised: 02/16/2009] [Accepted: 03/03/2009] [Indexed: 12/18/2022]
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Song KS, Choi YH, Kim JM, Lee H, Lee TJ, Yoon JH. Suppression of prostaglandin E2-induced MUC5AC overproduction by RGS4 in the airway. Am J Physiol Lung Cell Mol Physiol 2009; 296:L684-92. [PMID: 19201815 DOI: 10.1152/ajplung.90396.2008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mechanism by which E-prostanoid (EP) receptor is critically involved in PGE(2)-induced mucin 5AC (MUC5AC) gene expression in the airway has been unclear. Furthermore, there have been little reports regarding the negative regulatory mechanism and/or proteins that affect PGE(2)-induced MUC5AC overproduction. In the present study, we found that PGE(2) induced MUC5AC gene expression in a dose-dependent manner (EC(50): 73.31 +/- 3.13 nM) and that the EP(2/4)-specific agonist, misoprostol, increased MUC5AC mRNA level, whereas the EP(1/3)-specific agonist, sulprostone, had no effect. Interestingly, the cAMP concentration (685.1 +/- 14.9 pM) of the EC(50) value of EP(4)-mediated cAMP production was much higher than that of EP(2) (462.33 +/- 23.79 pM), suggesting that EP(4) has higher sensitivity to PGE(2) compared with EP(2). Moreover, PGE(2)-induced Muc5ac overproduction was much increased in regulator of G protein signaling (Rgs) 4 knockout (KO) mice compared with wild-type mice at both transcriptional and translational levels, and it was dramatically suppressed in Rgs4 KO mice that had been infected with lentivirus expressing RGS4 (lenti::RGS4) compared with lentivirus expressing enhanced green fluorescent protein (lenti::eGFP). Finally, we demonstrate that PGE(2) can induce MUC5AC overproduction via the EP(4) receptor and that RGS4 may have suppressive effects in controlling MUC5AC overexpression in the airway. These findings may provide a molecular paradigm for the development of novel drugs for respiratory diseases.
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Abstract
Adenosine (Ado) regulates diverse cellular functions in the lung through its local production, release, metabolism, and subsequent stimulation of G-protein-coupled P1 purinergic receptors. The A(2B) adenosine receptor (A(2B)AR) is the predominant P1 purinergic receptor isoform expressed in surface airway epithelia, and Ado is an important regulator of airway surface liquid (ASL) volume through its activation of the cystic fibrosis transmembrane conductance regulator (CFTR). Through a delicate balance between sodium (Na(+)) absorption and chloride (Cl(-)) secretion, the ASL volume is optimized to promote ciliary activity and mucociliary clearance, effectively removing inhaled particulates. When CFTR is dysfunctional, the Ado/A(2B)AR regulatory system fails to optimize the ASL volume, leading to its depletion and interruption of mucociliary clearance. In cystic fibrosis (CF), loss of CFTR function and resultant mucus stasis leaves the lower airways susceptible to mucus obstruction, chronic bacterial infection, relentless inflammation, and eventually panbronchiectasis. Adenosine triphosphate (ATP) also regulates transepithelial Cl(-) conductance, but through a separate system that relies on stimulation of P2Y(2) purinergic receptors, mobilization of intracellular calcium, and activation of calcium-activated chloride channels (CaCCs). These pathways remain functional in CF, and may serve a protective role in the disease. In this chapter, we will review our current understanding of how Ado and related nucleotides regulate CFTR and Cl(-) conductance in the human airway, including the regulation of additional intracellular and extracellular signaling pathways that provide important links between ion transport and inflammation relevant to the disease.
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Schwarzer C, Fischer H, Kim EJ, Barber KJ, Mills AD, Kurth MJ, Gruenert DC, Suh JH, Machen TE, Illek B. Oxidative stress caused by pyocyanin impairs CFTR Cl(-) transport in human bronchial epithelial cells. Free Radic Biol Med 2008; 45:1653-62. [PMID: 18845244 PMCID: PMC2628806 DOI: 10.1016/j.freeradbiomed.2008.09.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 08/25/2008] [Accepted: 09/01/2008] [Indexed: 11/22/2022]
Abstract
Pyocyanin (N-methyl-1-hydroxyphenazine), a redox-active virulence factor produced by the human pathogen Pseudomonas aeruginosa, is known to compromise mucociliary clearance. Exposure of human bronchial epithelial cells to pyocyanin increased the rate of cellular release of H(2)O(2) threefold above the endogenous H(2)O(2) production. Real-time measurements of the redox potential of the cytosolic compartment using the redox sensor roGFP1 showed that pyocyanin (100 microM) oxidized the cytosol from a resting value of -318+/-5 mV by 48.0+/-4.6 mV within 2 h; a comparable oxidation was induced by 100 microM H(2)O(2). Whereas resting Cl(-) secretion was slightly activated by pyocyanin (to 10% of maximal currents), forskolin-stimulated Cl(-) secretion was inhibited by 86%. The decline was linearly related to the cytosolic redox potential (1.8% inhibition/mV oxidation). Cystic fibrosis bronchial epithelial cells homozygous for DeltaF508 CFTR failed to secrete Cl(-) in response to pyocyanin or H(2)O(2), indicating that these oxidants specifically target the CFTR and not other Cl(-) conductances. Treatment with pyocyanin also decreased total cellular glutathione levels to 62% and cellular ATP levels to 46% after 24 h. We conclude that pyocyanin is a key factor that redox cycles in the cytosol, generates H(2)O(2), depletes glutathione and ATP, and impairs CFTR function in Pseudomonas-infected lungs.
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Affiliation(s)
- Christian Schwarzer
- Department of Molecular and Cell Biology, University of California, Berkeley, California
| | - Horst Fischer
- Nutrition and Metabolism Center, Children’s Hospital Oakland Research Institute, Oakland, California
| | - Eun-Jin Kim
- Nutrition and Metabolism Center, Children’s Hospital Oakland Research Institute, Oakland, California
| | - Katharine J. Barber
- Nutrition and Metabolism Center, Children’s Hospital Oakland Research Institute, Oakland, California
| | - Aaron D. Mills
- Department of Chemistry, University of California, Davis, California
| | - Mark J. Kurth
- Department of Chemistry, University of California, Davis, California
| | - Dieter C. Gruenert
- California Pacific Medical Center Research Institute, San Francisco, California
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, California
- Department of Medicine, University of Vermont, Burlington, Vermont
| | - Jung H. Suh
- Nutrition and Metabolism Center, Children’s Hospital Oakland Research Institute, Oakland, California
| | - Terry E. Machen
- Department of Molecular and Cell Biology, University of California, Berkeley, California
| | - Beate Illek
- Nutrition and Metabolism Center, Children’s Hospital Oakland Research Institute, Oakland, California
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30
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Abstract
A large body of evidence indicates that measurement of F2-isoprostanes, specific prostaglandin F2-like compounds derived from the non-enzymatic peroxidation of arachidonic acid, is a reliable biomarker of oxidant stress in the human body. Since the discovery of F2-isoprostanes in the early 1990s, a variety of analytical approaches has been introduced for the quantification of these novel compounds. The aim of the present review is to shed light on the available gas chromatographic–mass spectrometric assays for the measurement of plasma or urinary F2-isoprostanes and to highlight a number of issues which need to be addressed in order to implement F2-isoprostane measurement as a gold-standard biomarker of oxidative stress in biological samples.
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