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AlBloushi S, Al-Ahmad M. Exploring the immunopathology of type 2 inflammatory airway diseases. Front Immunol 2024; 15:1285598. [PMID: 38680486 PMCID: PMC11045947 DOI: 10.3389/fimmu.2024.1285598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 03/22/2024] [Indexed: 05/01/2024] Open
Abstract
Significant advancements have been achieved in understanding the roles of different immune cells, as well as cytokines and chemokines, in the pathogenesis of eosinophilic airway conditions. This review examines the pathogenesis of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), marked by complex immune dysregulation, with major contributions from type 2 inflammation and dysfunctional airway epithelium. The presence of eosinophils and the role of T-cell subsets, particularly an imbalance between Treg and Th17 cells, are crucial to the disease's pathogenesis. The review also investigates the pathogenesis of eosinophilic asthma, a unique asthma subtype. It is characterized by inflammation and high eosinophil levels, with eosinophils playing a pivotal role in triggering type 2 inflammation. The immune response involves Th2 cells, eosinophils, and IgE, among others, all activated by genetic and environmental factors. The intricate interplay among these elements, chemokines, and innate lymphoid cells results in airway inflammation and hyper-responsiveness, contributing to the pathogenesis of eosinophilic asthma. Another scope of this review is the pathogenesis of Eosinophilic Granulomatosis with Polyangiitis (EGPA); a complex inflammatory disease that commonly affects the respiratory tract and small to medium-sized blood vessels. It is characterized by elevated eosinophil levels in blood and tissues. The pathogenesis involves the activation of adaptive immune responses by antigens leading to T and B cell activation and eosinophil stimulation, which causes tissue and vessel damage. On the other hand, Allergic Bronchopulmonary Aspergillosis (ABPA) is a hypersensitive response that occurs when the airways become colonized by aspergillus fungus, with the pathogenesis involving activation of Th2 immune responses, production of IgE antibodies, and eosinophilic action leading to bronchial inflammation and subsequent lung damage. This analysis scrutinizes how an imbalanced immune system contributes to these eosinophilic diseases. The understanding derived from this assessment can steer researchers toward designing new potential therapeutic targets for efficient control of these disorders.
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Affiliation(s)
| | - Mona Al-Ahmad
- Al-Rashed Allergy Center, Ministry of Health, Kuwait City, Kuwait
- Microbiology Department, College of Medicine, Kuwait University, Kuwait City, Kuwait
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2
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Ruhl A, Antão AV, Dietschmann A, Radtke D, Tenbusch M, Voehringer D. STAT6-induced production of mucus and resistin-like molecules in lung Club cells does not protect against helminth or influenza A virus infection. Eur J Immunol 2024; 54:e2350558. [PMID: 37855177 DOI: 10.1002/eji.202350558] [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: 05/08/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/20/2023]
Abstract
Airway epithelial cells contribute to a variety of lung diseases including allergic asthma, where IL-4 and IL-13 promote activation of the transcription factor STAT6. This leads to goblet cell hyperplasia and the secretion of effector molecules by epithelial cells. However, the specific effect of activated STAT6 in lung epithelial cells is only partially understood. Here, we created a mouse strain to selectively investigate the role of constitutively active STAT6 in Club cells, a subpopulation of airway epithelial cells. CCSP-Cre_STAT6vt mice and bronchiolar organoids derived from these show an enhanced expression of the chitinase-like protein Chil4 (Ym2) and resistin-like molecules (Relm-α, -β, -γ). In addition, goblet cells of these mice spontaneously secrete mucus into the bronchi. However, the activated epithelium resulted neither in impaired lung function nor conferred a protective effect against the migrating helminth Nippostrongylus brasiliensis. Moreover, CCSP-Cre_STAT6vt mice showed similar allergic airway inflammation induced by live conidia of the fungus Aspergillus fumigatus and similar recovery after influenza A virus infection compared to control mice. Together these results highlight that STAT6 signaling in Club cells induces the secretion of Relm proteins and mucus without impairing lung function, but this is not sufficient to confer protection against helminth or viral infections.
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Affiliation(s)
- Andreas Ruhl
- Infektionsbiologische Abteilung, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Ana Vieira Antão
- Institut für klinische und molekulare Virologie, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Axel Dietschmann
- Infektionsbiologische Abteilung, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Daniel Radtke
- Infektionsbiologische Abteilung, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias Tenbusch
- Institut für klinische und molekulare Virologie, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Medical Immunology Campus Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - David Voehringer
- Infektionsbiologische Abteilung, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Medical Immunology Campus Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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3
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Kanti MM, Striessnig-Bina I, Wieser BI, Schauer S, Leitinger G, Eichmann TO, Schweiger M, Winkler M, Winter E, Lana A, Kufferath I, Marsh LM, Kwapiszewska G, Zechner R, Hoefler G, Vesely PW. Adipose triglyceride lipase-mediated lipid catabolism is essential for bronchiolar regeneration. JCI Insight 2022; 7:e149438. [PMID: 35349484 PMCID: PMC9090255 DOI: 10.1172/jci.insight.149438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 03/23/2022] [Indexed: 01/18/2023] Open
Abstract
The lung airways are constantly exposed to inhaled toxic substances, resulting in cellular damage that is repaired by local expansion of resident bronchiolar epithelial club cells. Disturbed bronchiolar epithelial damage repair lies at the core of many prevalent lung diseases, including chronic obstructive pulmonary disease, asthma, pulmonary fibrosis, and lung cancer. However, it is still not known how bronchiolar club cell energy metabolism contributes to this process. Here, we show that adipose triglyceride lipase (ATGL), the rate-limiting enzyme for intracellular lipolysis, is critical for normal club cell function in mice. Deletion of the gene encoding ATGL, Pnpla2 (also known as Atgl), induced substantial triglyceride accumulation, decreased mitochondrial numbers, and decreased mitochondrial respiration in club cells. This defect manifested as bronchiolar epithelial thickening and increased airway resistance under baseline conditions. After naphthalene‑induced epithelial denudation, a regenerative defect was apparent. Mechanistically, dysfunctional PPARα lipid-signaling underlies this phenotype because (a) ATGL was needed for PPARα lipid-signaling in regenerating bronchioles and (b) administration of the specific PPARα agonist WY14643 restored normal bronchiolar club cell ultrastructure and regenerative potential. Our data emphasize the importance of the cellular energy metabolism for lung epithelial regeneration and highlight the significance of ATGL-mediated lipid catabolism for lung health.
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Affiliation(s)
- Manu Manjunath Kanti
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Isabelle Striessnig-Bina
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Beatrix Irene Wieser
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Silvia Schauer
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Gerd Leitinger
- BioTechMed-Graz, Graz, Austria
- Division of Cell Biology, Histology, and Embryology, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Thomas O. Eichmann
- BioTechMed-Graz, Graz, Austria
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
- Core Facility Mass Spectrometry, Medical University of Graz, Graz, Austria
| | - Martina Schweiger
- BioTechMed-Graz, Graz, Austria
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Margit Winkler
- BioTechMed-Graz, Graz, Austria
- Institute of Molecular Biotechnology, NAWI Graz, Graz University of Technology, Graz, Austria
| | - Elke Winter
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Andrea Lana
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Iris Kufferath
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Leigh Matthew Marsh
- BioTechMed-Graz, Graz, Austria
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Otto Loewi Research Center, Medical University of Graz, Graz, Austria
| | - Grazyna Kwapiszewska
- BioTechMed-Graz, Graz, Austria
- Ludwig Boltzmann Institute for Lung Vascular Research, Graz, Austria
- Otto Loewi Research Center, Medical University of Graz, Graz, Austria
- Institute for Lung Health, Giessen, Germany
| | - Rudolf Zechner
- BioTechMed-Graz, Graz, Austria
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Gerald Hoefler
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Paul Willibald Vesely
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria
- BioTechMed-Graz, Graz, Austria
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Alfaro-Arnedo E, López IP, Piñeiro-Hermida S, Ucero ÁC, González-Barcala FJ, Salgado FJ, Pichel JG. IGF1R as a Potential Pharmacological Target in Allergic Asthma. Biomedicines 2021; 9:biomedicines9080912. [PMID: 34440118 PMCID: PMC8389607 DOI: 10.3390/biomedicines9080912] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 07/22/2021] [Accepted: 07/24/2021] [Indexed: 12/21/2022] Open
Abstract
Background: Asthma is a chronic lung disease characterized by reversible airflow obstruction, airway hyperresponsiveness (AHR), mucus overproduction and inflammation. Although Insulin-like growth factor 1 receptor (IGF1R) was found to be involved in asthma, its pharmacological inhibition has not previously been investigated in this pathology. We aimed to determine if therapeutic targeting of IGF1R ameliorates allergic airway inflammation in a murine model of asthma. Methods: C57BL/6J mice were challenged by house dust mite (HDM) extract or PBS for four weeks and therapeutically treated with the IGF1R tyrosine kinase inhibitor (TKI) NVP-ADW742 (NVP) once allergic phenotype was established. Results: Lungs of HDM-challenged mice exhibited a significant increase in phospho-IGF1R levels, incremented AHR, airway remodeling, eosinophilia and allergic inflammation, as well as altered pulmonary surfactant expression, all of being these parameters counteracted by NVP treatment. HDM-challenged lungs also displayed augmented expression of the IGF1R signaling mediator p-ERK1/2, which was greatly reduced upon treatment with NVP. Conclusions: Our results demonstrate that IGF1R could be considered a potential pharmacological target in murine HDM-induced asthma and a candidate biomarker in allergic asthma.
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Affiliation(s)
- Elvira Alfaro-Arnedo
- Lung Cancer and Respiratory Diseases Unit, Center for Biomedical Research of La Rioja (CIBIR), Fundación Rioja Salud, 26006 Logroño, Spain; (E.A.-A.); (I.P.L.)
| | - Icíar P. López
- Lung Cancer and Respiratory Diseases Unit, Center for Biomedical Research of La Rioja (CIBIR), Fundación Rioja Salud, 26006 Logroño, Spain; (E.A.-A.); (I.P.L.)
| | - Sergio Piñeiro-Hermida
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), 28029 Madrid, Spain;
| | - Álvaro C. Ucero
- Thoracic Oncology, Research Institute Hospital 12 de Octubre, 28041 Madrid, Spain;
- Department of Physiology, Faculty of Medicine, Complutense University, 28040 Madrid, Spain
| | - Francisco J. González-Barcala
- Department of Respiratory Medicine, University Hospital of Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain;
- Health Research Institute of Santiago de Compostela (FIDIS), 15706 Santiago de Compostela, Spain
- Spanish Biomedical Research Networking Centre-CIBERES, 15706 Santiago de Compostela, Spain
| | - Francisco J. Salgado
- Department of Biochemistry and Molecular Biology, Faculty of Biology-Biological Research Centre (CIBUS), Universidad de Santiago de Compostela, 15706 Santiago de Compostela, Spain;
| | - José G. Pichel
- Lung Cancer and Respiratory Diseases Unit, Center for Biomedical Research of La Rioja (CIBIR), Fundación Rioja Salud, 26006 Logroño, Spain; (E.A.-A.); (I.P.L.)
- Spanish Biomedical Research Networking Centre-CIBERES, 15706 Santiago de Compostela, Spain
- Correspondence: ; Tel.: +34-638-056-014
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Piñeiro‐Hermida S, Martínez P, Blasco MA. Short and dysfunctional telomeres protect from allergen-induced airway inflammation. Aging Cell 2021; 20:e13352. [PMID: 33942458 PMCID: PMC8135011 DOI: 10.1111/acel.13352] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 02/22/2021] [Accepted: 03/07/2021] [Indexed: 12/17/2022] Open
Abstract
Asthma is a chronic inflammatory disease affecting 300 million people worldwide. As telomere shortening is a well-established hallmark of aging and that asthma incidence decreases with age, here we aimed to study the role of short telomeres in asthma pathobiology. To this end, wild-type and telomerase-deficient mice with short telomeres (third-generation (G3 Tert-/- mice)) were challenged with intranasal house dust mite (HDM) extract. We also challenged with HDM wild-type mice in which we induced a telomere dysfunction by the administration of 6-thio-2´-deoxyguanosine (6-thio-dG). Following HDM exposure, G3 Tert-/- and 6-thio-dG treated mice exhibited attenuated eosinophil counts and presence of hematopoietic stem cells in the bone marrow, as well as lower levels of IgE and circulating eosinophils. Accordingly, both G3 Tert-/- and 6-thio-dG treated wild-type mice displayed reduced airway hyperresponsiveness (AHR), as indicated by decreased airway remodeling and allergic airway inflammation markers in the lung. Furthermore, G3 Tert-/- and 6-thio-dG treated mice showed lower differentiation of Club cells, attenuating goblet cell hyperplasia. Club cells of G3 Tert-/- and 6-thio-dG treated mice displayed increased DNA damage and senescence and reduced proliferation. Thus, short/dysfunctional telomeres play a protective role in murine asthma by impeding both AHR and mucus secretion after HDM exposure. Therefore, our findings imply that telomeres play a relevant role in allergen-induced airway inflammation.
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Affiliation(s)
- Sergio Piñeiro‐Hermida
- Telomeres and Telomerase Group Molecular Oncology Program Spanish National Cancer Centre (CNIO) Madrid Spain
| | - Paula Martínez
- Telomeres and Telomerase Group Molecular Oncology Program Spanish National Cancer Centre (CNIO) Madrid Spain
| | - Maria A. Blasco
- Telomeres and Telomerase Group Molecular Oncology Program Spanish National Cancer Centre (CNIO) Madrid Spain
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Neonatal endotoxin stimulation is associated with a long-term bronchiolar epithelial expression of innate immune and anti-allergic markers that attenuates the allergic response. PLoS One 2020; 15:e0226233. [PMID: 32379832 PMCID: PMC7205282 DOI: 10.1371/journal.pone.0226233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 04/22/2020] [Indexed: 11/19/2022] Open
Abstract
Allergic asthma is the most common phenotype of the pathology, having an early-onset in childhood and producing a Th2-driven airways remodeling process that leads to symptoms and pathophysiological changes. The avoidance of aeroallergen exposure in early life has been shown to prevent asthma, but without repeated success and with the underlying preventive mechanisms at the beginning of asthma far to be fully recognized. In the present study, we aimed to evaluate if neonatal LPS-induced boost in epithelial host defenses contribute to prevent OVA-induced asthma in adult mice. To this, we focused on the response of bronchiolar club cells (CC), which are highly specialized in maintaining the epithelial homeostasis in the lung. In these cells, neonatal LPS administration increased the expression of TLR4 and TNFα, as well as the immunodulatory/antiallergic proteins: club cell secretory protein (CCSP) and surfactant protein D (SP-D). LPS also prevented mucous metaplasia of club cells and reduced the epidermal growth factor receptor (EGFR)-dependent mucin overproduction, with mice displaying normal breathing patterns after OVA challenge. Furthermore, the overexpression of the epithelial Th2-related molecule TSLP was blunted, and normal TSLP and IL-4 levels were found in the bronchoalveolar lavage. A lower eosinophilia was detected in LPS-pretreated mice, along with an increase in phagocytes and regulatory cells (CD4+CD25+FOXP3+ and CD4+IL-10+), together with higher levels of IL-12 and TNFα. In conclusion, our study demonstrates stable asthma-preventive epithelial effects promoted by neonatal LPS stimulation, leading to the presence of regulatory cells in the lung. These anti-allergic dynamic mechanisms would be overlaid in the epithelium, favored by an adequate epidemiological environment, during the development of asthma.
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Protective Effects of Licochalcone A Improve Airway Hyper-Responsiveness and Oxidative Stress in a Mouse Model of Asthma. Cells 2019; 8:cells8060617. [PMID: 31226782 PMCID: PMC6628120 DOI: 10.3390/cells8060617] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 06/18/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022] Open
Abstract
Licochalcone A was isolated from Glycyrrhiza uralensis and previously reported to have antitumor and anti-inflammatory effects. Licochalcone A has also been found to inhibit the levels of Th2-associated cytokines in the bronchoalveolar lavage fluid (BALF) of asthmatic mice. However, the molecular mechanism underlying airway inflammation and how licochalcone A regulates oxidative stress in asthmatic mice are elusive. In this study, we investigated whether licochalcone A could attenuate inflammatory and oxidative responses in tracheal epithelial cells, and whether it could ameliorate oxidative stress and airway inflammation in asthmatic mice. Inflammatory human tracheal epithelial (BEAS-2B) cells were treated with licochalcone A to evaluate oxidative responses and inflammatory cytokine levels. In addition, BALB/c mice were sensitized with ovalbumin (OVA) and injected intraperitoneally with licochalcone A (5 or 10 mg/kg). Licochalcone A significantly inhibited reactive oxygen species, eotaxin, and proinflammatory cytokines in BEAS-2B cells. Licochalcone A also decreased intercellular adhesion molecule 1 levels in inflammatory BEAS-2B cells, blocking monocyte cell adherence. We also found that licochalcone A significantly decreased oxidative responses, reduced malondialdehyde levels, and increased glutathione levels in the lungs of OVA-sensitized mice. Furthermore, licochalcone A decreased airway hyper-responsiveness, eosinophil infiltration, and Th2 cytokine production in the BALF. These findings suggest that licochalcone A alleviates oxidative stress, inflammation, and pathological changes by inhibiting Th2-associated cytokines in asthmatic mice and human tracheal epithelial cells. Thus, licochalcone A demonstrated therapeutic potential for improving asthma.
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Chen S, Yu G, Xie J, Tang W, Gao L, Long X, Ren L, Xie X, Deng Y, Fu Z, Liu E. High-mobility group box-1 protein from CC10 + club cells promotes type 2 response in the later stage of respiratory syncytial virus infection. Am J Physiol Lung Cell Mol Physiol 2018; 316:L280-L290. [PMID: 30407867 DOI: 10.1152/ajplung.00552.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The type 2 immune response, induced by infection of respiratory syncytial virus (RSV), has been linked to asthma development, but it remains unclear how the response is initiated. Here, we reported that the high-mobility group box-1 (HMGB1) protein promotes the type 2 response in the later stage of RSV infection. In mice, we found that type 2 cytokines were elevated in the later stages, which were strongly diminished after administration of anti-HMGB1 antibodies. Further investigation revealed that HMGB1 expression was localized to CC10+ club cells in the lung. In the clinic, levels of HMGB1 in nasopharyngeal aspirates in hospitalized infants with RSV bronchiolitis [median (interquartile range) 161.20 ng/ml (68.06-221.30)] were significantly higher than those without lower respiratory tract infections [21.94 ng/ml (12.12-59.82); P < 0.001]. Moreover, higher levels of HMGB1 correlated with clinical severity. These results reveal a link between viral infection and the asthma-like type 2 responses that are associated with long-term consequences.
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Affiliation(s)
- Sisi Chen
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Guangyuan Yu
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Jun Xie
- Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Wei Tang
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Leiqiong Gao
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Xiaoru Long
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Luo Ren
- Ministry of Education Key Laboratory of Child Development and Disorders; Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Xiaohong Xie
- Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Yu Deng
- Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Zhou Fu
- Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University , Chongqing , China
| | - Enmei Liu
- Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University , Chongqing , China
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Oh JY, Lee YS, Min KH, Hur GY, Lee SY, Kang KH, Rhee CK, Park SJ, Shim JJ. Decreased serum club cell secretory protein in asthma and chronic obstructive pulmonary disease overlap: a pilot study. Int J Chron Obstruct Pulmon Dis 2018; 13:3411-3417. [PMID: 30425470 PMCID: PMC6203108 DOI: 10.2147/copd.s174545] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Purpose Improvement in the diagnosis of asthma and chronic obstructive pulmonary disease (COPD) overlap (ACO), and identification of biomarkers for phenotype recognition will encourage good patient care by providing optimal therapy. We investigated club cell secretory protein (CC-16), a protective and anti-inflammatory mediator, as a new candidate biomarker for diagnosing ACO. Patients and methods We performed a multicenter cohort study. A total of 107 patients were divided into three groups - asthma, COPD, and ACO - according to the Spanish guidelines algorithm, and enrolled into the study. Serum CC-16 levels were measured using commercial ELISA kits. Results Serum CC-16 levels were the lowest in patients with ACO. Low serum CC-16 levels were a significant marker for the ACO even after adjustment for age, sex, and smoking intensity. Serum CC-16 levels were positively correlated with forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), forced expiratory flow at 25%-75% of FVC, FEV1/FVC, vital capacity, and diffusing capacity of the lung for carbon monoxide, and were negatively correlated with smoking amount (pack-years), bronchodilator response, fractional residual capacity, residual volume, and number of exacerbations per year. FEV1 and serum CC-16 levels were significantly lower in patients with frequent exacerbations. Conclusion Serum CC-16 has the potential to be a biomarker for ACO diagnosis and also treat frequent exacerbations in patients with chronic inflammatory airway diseases.
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Affiliation(s)
- Jee Youn Oh
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Young Seok Lee
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Kyung Hoon Min
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Gyu Young Hur
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Sung Yong Lee
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Kyung Ho Kang
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
| | - Chin Kook Rhee
- Division of Pulmonary Medicine, Department of Internal Medicine, Catholic University Seoul Hospital, Seoul, Republic of Korea
| | - Seoung Ju Park
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Republic of Korea
| | - Jae Jeong Shim
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Korea University Guro Hospital, Seoul, Republic of Korea,
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Castro-Rodriguez J, Atton I, Villarroel G, Serrano C. Relation between serum CC16 levels and asthma predictive index in pre-schoolers with recurrent wheezing. Allergol Immunopathol (Madr) 2018; 46:460-466. [PMID: 29685782 DOI: 10.1016/j.aller.2017.09.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/13/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND Low levels of serum CC16 were reported in asthmatic adults, but the studies on children were scarce and conflicting. The aim of this study was to compare serum CC16 levels in pre-school children with recurrent wheezing assessed using an asthma predictive index (API). METHODS We performed a case-control study based on API, with all enrolled pre-school children who had recurrent wheezing episodes (>3 episodes/last year confirmed by a physician) and had presented at one paediatric clinic in Santiago, Chile. The population was divided according to stringent API criteria into positive or negative. RESULTS In a one-year period, 60 pre-schoolers were enrolled. After excluding 12, 48 pre-schoolers remained (27 males, age range from 24 to 71 months) and completed the study; 34 were API positive and 14 were API negative. There were no significant differences in demographics between groups. The level of serum CC16 levels for pre-schoolers with a positive API and negative API were (median 9.2 [7.1-11.5] and 9.4 [5.5-10], p=0.26, respectively). The area under the curve for the serum CC16 levels to predict a positive API was 0.6, 95% CI [0.43-0.77], p=0.3. A correlation between serum CC16 levels and age was found (r=0.36 [0.07-0.59], p=0.01], but not between serum CC16 levels and peripheral eosinophils blood. CONCLUSION There was no evidence that serum CC16 levels played a role in recurrent wheezing and a positive API in pre-school children. More studies are needed to confirm this finding.
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Characterization of the acute inflammatory profile and resolution of airway inflammation after Igf1r-gene targeting in a murine model of HDM-induced asthma. PLoS One 2017; 12:e0190159. [PMID: 29272313 PMCID: PMC5741234 DOI: 10.1371/journal.pone.0190159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 12/08/2017] [Indexed: 01/25/2023] Open
Abstract
Asthma is a chronic inflammatory disease characterized by bronchial hyperresponsiveness, mucus overproduction and airway remodeling. Notably, we have recently demonstrated that insulin-like growth factor 1 receptor (IGF1R) deficiency in mice attenuates airway hyperresponsiveness and mucus secretion after chronic house dust mite (HDM) exposure. On this basis, inbred C57BL/6 and Igf1r-deficient mice were given HDM extract to study the acute inflammatory profile and implication of Igf1r in acute asthma pathobiology. Additionally, Igf1r-deficiency was therapeutically induced in mice to evaluate the resolution of HDM-induced inflammation. Acute HDM exposure in inbred C57BL/6 mice led to a progressive increase in inflammation, airway remodeling and associated molecular indicators. Preventively-induced Igf1r-deficiency showed reduced neutrophil and eosinophil numbers in BALF and bone marrow, a significant reduction of airway remodeling and decreased levels of related markers. In addition, therapeutic targeting of Igf1r promoted the resolution of HDM-induced-inflammation. Our results demonstrate for the first time that Igf1r is important in acute asthma pathobiology and resolution of HDM-induced inflammation. Thus, IGF1R is suggested to be a promising candidate for future therapeutic approaches for the treatment and prevention of asthma.
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12
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Sebag SC, Koval OM, Paschke JD, Winters CJ, Jaffer OA, Dworski R, Sutterwala FS, Anderson ME, Grumbach IM. Mitochondrial CaMKII inhibition in airway epithelium protects against allergic asthma. JCI Insight 2017; 2:e88297. [PMID: 28194433 DOI: 10.1172/jci.insight.88297] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Excessive ROS promote allergic asthma, a condition characterized by airway inflammation, eosinophilic inflammation, and increased airway hyperreactivity (AHR). The mechanisms by which airway ROS are increased and the relationship between increased airway ROS and disease phenotypes are incompletely defined. Mitochondria are an important source of cellular ROS production, and our group discovered that Ca2+/calmodulin-dependent protein kinase II (CaMKII) is present in mitochondria and activated by oxidation. Furthermore, mitochondrial-targeted antioxidant therapy reduced the severity of allergic asthma in a mouse model. Based on these findings, we developed a mouse model of CaMKII inhibition targeted to mitochondria in airway epithelium. We challenged these mice with OVA or Aspergillus fumigatus. Mitochondrial CaMKII inhibition abrogated AHR, inflammation, and eosinophilia following OVA and A. fumigatus challenge. Mitochondrial ROS were decreased after agonist stimulation in the presence of mitochondrial CaMKII inhibition. This correlated with blunted induction of NF-κB, the NLRP3 inflammasome, and eosinophilia in transgenic mice. These findings demonstrate a pivotal role for mitochondrial CaMKII in airway epithelium in mitochondrial ROS generation, eosinophilic inflammation, and AHR, providing insights into how mitochondrial ROS mediate features of allergic asthma.
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Affiliation(s)
- Sara C Sebag
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Olha M Koval
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA.,Veterans Affairs Healthcare System, Iowa City, Iowa, USA
| | - John D Paschke
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | | | - Omar A Jaffer
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Ryszard Dworski
- Division of Allergy, Pulmonary and Critical Care Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Fayyaz S Sutterwala
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA.,Veterans Affairs Healthcare System, Iowa City, Iowa, USA.,Inflammation Program, University of Iowa, Iowa City, Iowa, USA.,Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Mark E Anderson
- Department of Medicine and.,Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Isabella M Grumbach
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa, USA.,Veterans Affairs Healthcare System, Iowa City, Iowa, USA
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13
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Biomarker as a research tool in linking exposure to air particles and respiratory health. BIOMED RESEARCH INTERNATIONAL 2015; 2015:962853. [PMID: 25984536 PMCID: PMC4422993 DOI: 10.1155/2015/962853] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 08/11/2014] [Accepted: 09/08/2014] [Indexed: 01/08/2023]
Abstract
Some of the environmental toxicants from air pollution include particulate matter (PM10), fine particulate matter (PM2.5), and ultrafine particles (UFP). Both short- and long-term exposure could result in various degrees of respiratory health outcomes among exposed persons, which rely on the individuals' health status. Methods. In this paper, we highlight a review of the studies that have used biomarkers to understand the association between air particles exposure and the development of respiratory problems resulting from the damage in the respiratory system. Data from previous epidemiological studies relevant to the application of biomarkers in respiratory system damage reported from exposure to air particles are also summarized. Results. Based on these analyses, the findings agree with the hypothesis that biomarkers are relevant in linking harmful air particles concentrations to increased respiratory health effects. Biomarkers are used in epidemiological studies to provide an understanding of the mechanisms that follow airborne particles exposure in the airway. However, application of biomarkers in epidemiological studies of health effects caused by air particles in both environmental and occupational health is inchoate. Conclusion. Biomarkers unravel the complexity of the connection between exposure to air particles and respiratory health.
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14
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García LN, Leimgruber C, Uribe Echevarría EM, Acosta PL, Brahamian JM, Polack FP, Miró MS, Quintar AA, Sotomayor CE, Maldonado CA. Protective phenotypes of club cells and alveolar macrophages are favored as part of endotoxin-mediated prevention of asthma. Exp Biol Med (Maywood) 2014; 240:904-16. [PMID: 25504013 DOI: 10.1177/1535370214562338] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 10/20/2014] [Indexed: 12/31/2022] Open
Abstract
Atopic asthma is a chronic allergic disease that involves T-helper type 2 (Th2)-inflammation and airway remodeling. Bronchiolar club cells (CC) and alveolar macrophages (AM) are sentinel cells of airway barrier against inhaled injuries, where allergy induces mucous metaplasia of CC and the alternative activation of AM, which compromise host defense mechanisms and amplify Th2-inflammation. As there is evidence that high levels of environmental endotoxin modulates asthma, the goal of this study was to evaluate if the activation of local host defenses by Lipopolysaccharide (LPS) previous to allergy development can contribute to preserving CC and AM protective phenotypes. Endotoxin stimulus before allergen exposition reduced hallmarks of allergic inflammation including eosinophil influx, Interleukin-4 and airway hyperreactivity, while the T-helper type 1 related cytokines IL-12 and Interferon-γ were enhanced. This response was accompanied by the preservation of the normal CC phenotype and the anti-allergic proteins Club Cell Secretory Protein (CCSP) and Surfactant-D, thereby leading to lower levels of CC metaplasia and preventing the increase of the pro-Th2 cytokine Thymic stromal lymphopoietin. In addition, classically activated alveolar macrophages expressing nitric oxide were promoted over the alternatively activated ones that expressed arginase-1. We verified that LPS induced a long-term overexpression of CCSP and the innate immune markers Toll-like receptor 4, and Tumor Necrosis Factor-α, changes that were preserved in spite of the allergen challenge. These results demonstrate that LPS pre-exposition modifies the local bronchioalveolar microenvironment by inducing natural anti-allergic mechanisms while reducing local factors that drive Th2 type responses, thus modulating allergic inflammation.
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Affiliation(s)
- Luciana N García
- Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Centro de Microscopía Electrónica- Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enrique Barros esq. Enfermera Gordillo, Ciudad Universitaria X5000HRA, Córdoba, Argentina
| | - Carolina Leimgruber
- Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Centro de Microscopía Electrónica- Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enrique Barros esq. Enfermera Gordillo, Ciudad Universitaria X5000HRA, Córdoba, Argentina
| | - Elisa M Uribe Echevarría
- Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Centro de Microscopía Electrónica- Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enrique Barros esq. Enfermera Gordillo, Ciudad Universitaria X5000HRA, Córdoba, Argentina
| | - Patricio L Acosta
- Fundación INFANT, Gavilan 94 C1406ABC, Capital Federal, Buenos Aires, Argentina
| | - Jorge M Brahamian
- Fundación INFANT, Gavilan 94 C1406ABC, Capital Federal, Buenos Aires, Argentina
| | - Fernando P Polack
- Fundación INFANT, Gavilan 94 C1406ABC, Capital Federal, Buenos Aires, Argentina Department of Pediatrics, Vanderbilt University, MCN, Vanderbilt University, Nashville, TN 37232, USA
| | - María S Miró
- Centro de Investigación en Bioquímica Clínica e Inmunología (CIBICI), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende (X5000HRA), Ciudad Universitaria, Córdoba, Argentina
| | - Amado A Quintar
- Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Centro de Microscopía Electrónica- Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enrique Barros esq. Enfermera Gordillo, Ciudad Universitaria X5000HRA, Córdoba, Argentina
| | - Claudia E Sotomayor
- Centro de Investigación en Bioquímica Clínica e Inmunología (CIBICI), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende (X5000HRA), Ciudad Universitaria, Córdoba, Argentina
| | - Cristina A Maldonado
- Instituto de Investigaciones en Ciencias de la Salud (INICSA), CONICET and Centro de Microscopía Electrónica- Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Enrique Barros esq. Enfermera Gordillo, Ciudad Universitaria X5000HRA, Córdoba, Argentina
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15
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Abstract
The bronchial epithelium has been increasingly recognized as an important immunomodulatory compartment in asthma and other lung diseases. Clara cells, which comprise the nonciliated secretory epithelial cells, are an important epithelial cell type with functions in the regulation of lung homeostasis and inflammation. Using naphthalene, Clara cells can be depleted within 24 h and regenerate by 1 month, hence, providing an easy method to study the impact of Clara cells on lung inflammation.
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Elango N, Kasi V, Vembhu B, Poornima JG. Chronic exposure to emissions from photocopiers in copy shops causes oxidative stress and systematic inflammation among photocopier operators in India. Environ Health 2013; 12:78. [PMID: 24025094 PMCID: PMC3849716 DOI: 10.1186/1476-069x-12-78] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 08/30/2013] [Indexed: 05/02/2023]
Abstract
BACKGROUND We assessed indoor air quality in photocopier centers and investigated whether occupational exposure to emissions from photocopiers is associated with decline in lung function or changes in haematological parameters, oxidative stress and inflammatory status. METHODS Indoor air quality was monitored in five photocopier centers. Pulmonary function was assessed by spirometry in 81 photocopier operators (64 male and 17 female) and 43 healthy control (31 male and 12 female) subjects. Hematological status, serum thio-barbituric acid reactive substances (TBARS), total ferric reducing antioxidant capacity (FRAC), leukotriene B4 (LTB4), 8-isoprostane, C reactive protein (CRP), interleukin 8 (IL-8), clara cell protein (CC-16), intercellular adhesion molecule 1 (ICAM-1) and eosinophilic cationic protein (ECP) were analyzed. Relationships between cumulative exposure, lung function and inflammatory markers were assessed. RESULTS PM10 and PM2.5 were above the permissible levels in all the photocopier centers, whereas the levels of carbon monoxide, nitrogen oxides, ozone, sulphur dioxide, lead, arsenic, nickel, ammonia, benzene and benzo(a)pyrene were within Indian ambient air quality standards. Lung function was similar in the photocopier operators and control subjects. Serum TBARS was significantly higher and FRAC was lower among photocopier operators when compared to healthy controls. Plasma IL-8, LTB4, ICAM-1 and ECP were significantly higher in the photocopier exposed group. CONCLUSIONS Photocopiers emit high levels of particulate matter. Long term exposure to emissions from photocopiers was not associated with decreased lung function, but resulted in high oxidative stress and systemic inflammation leading to high risk of cardiovascular diseases.
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Affiliation(s)
- Nithya Elango
- Department of Biochemistry, Biotechnology and Bioinformatics Avinashilingam Institute for Home Science and Higher Education for Women Coimbatore, Tamilnadu, India
| | - Vallikkannu Kasi
- Department of Biochemistry, Biotechnology and Bioinformatics Avinashilingam Institute for Home Science and Higher Education for Women Coimbatore, Tamilnadu, India
| | - Bhuvaneswari Vembhu
- Department of Biochemistry, Biotechnology and Bioinformatics Avinashilingam Institute for Home Science and Higher Education for Women Coimbatore, Tamilnadu, India
| | - Jeyanthi Govindasamy Poornima
- Department of Biochemistry, Biotechnology and Bioinformatics Avinashilingam Institute for Home Science and Higher Education for Women Coimbatore, Tamilnadu, India
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Possa SS, Leick EA, Prado CM, Martins MA, Tibério IFLC. Eosinophilic inflammation in allergic asthma. Front Pharmacol 2013; 4:46. [PMID: 23616768 PMCID: PMC3627984 DOI: 10.3389/fphar.2013.00046] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Accepted: 03/28/2013] [Indexed: 01/21/2023] Open
Abstract
Eosinophils are circulating granulocytes involved in pathogenesis of asthma. A cascade of processes directed by Th2 cytokine producing T-cells influence the recruitment of eosinophils into the lungs. Furthermore, multiple elements including interleukin (IL)-5, IL-13, chemoattractants such as eotaxin, Clara cells, and CC chemokine receptor (CCR)3 are already directly involved in recruiting eosinophils to the lung during allergic inflammation. Once recruited, eosinophils participate in the modulation of immune response, induction of airway hyperresponsiveness and remodeling, characteristic features of asthma. Various types of promising treatments for reducing asthmatic response are related to reduction in eosinophil counts both in human and experimental models of pulmonary allergic inflammation, showing that the recruitment of these cells really plays an important role in the pathophysiology of allergic diseases such asthma.
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Affiliation(s)
- Samantha S Possa
- Department of Medicine, School of Medicine, University of São Paulo São Paulo, Brazil
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18
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Hanna-Mitchell AT, Ruiz GW, Daneshgari F, Liu G, Apodaca G, Birder LA. Impact of diabetes mellitus on bladder uroepithelial cells. Am J Physiol Regul Integr Comp Physiol 2012; 304:R84-93. [PMID: 23174855 DOI: 10.1152/ajpregu.00129.2012] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Diabetic bladder dysfunction (DBD), a prevalent complication of diabetes mellitus (DM), is characterized by a broad spectrum of symptoms including urinary urgency, frequency, and incontinence. As DBD is commonly diagnosed late, it is important to understand the chronic impact of DM on bladder tissues. While changes in bladder smooth muscle and innervation have been reported in diabetic patients, the impact of DM on the specialized epithelial lining of the urinary bladder, the urothelium (UT), is largely unknown. Quantitative polymerase chain reaction analysis and electron microscopy were used to evaluate UT gene expression and cell morphology 3, 9, and 20 wk following streptozotocin (STZ) induction of DM in female Sprague-Dawley rats compared with age-matched control tissue. Desquamation of superficial (umbrella) cells was noted at 9 wk DM, indicating a possible breach in barrier function. One causative factor may be metabolic burden due to chronic hyperglycemia, suggested by upregulation of the polyol pathway and glucose transport genes in DM UT. While superficial UT repopulation occurred by 20 wk DM, the phenotype was different, with significant upregulation of receptors associated with UT mechanosensation (transient receptor potential vanilloid subfamily member 1; TRPV1) and UT autocrine/paracrine signaling (acetylcholine receptors AChR-M2 and -M3, purinergic receptors P2X(2) and P2X(3)). Compromised barrier function and alterations in UT mechanosensitivity and cell signaling could contribute to bladder instability, hyperactivity, and altered bladder sensation by modulating activity of afferent nerve endings, which appose the urothelium. Our results show that DM impacts urothelial homeostasis and may contribute to the underlying mechanisms of DBD.
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