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Raith M, Swoboda I. Birch pollen-The unpleasant herald of spring. FRONTIERS IN ALLERGY 2023; 4:1181675. [PMID: 37255542 PMCID: PMC10225653 DOI: 10.3389/falgy.2023.1181675] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/24/2023] [Indexed: 06/01/2023] Open
Abstract
Type I respiratory allergies to birch pollen and pollen from related trees of the order Fagales are increasing in industrialized countries, especially in the temperate zone of the Northern hemisphere, but the reasons for this increase are still debated and seem to be multifaceted. While the most important allergenic molecules of birch pollen have been identified and characterized, the contribution of other pollen components, such as lipids, non-allergenic immunomodulatory proteins, or the pollen microbiome, to the development of allergic reactions are sparsely known. Furthermore, what also needs to be considered is that pollen is exposed to external influences which can alter its allergenicity. These external influences include environmental factors such as gaseous pollutants like ozone or nitrogen oxides or particulate air pollutants, but also meteorological events like changes in temperature, humidity, or precipitation. In this review, we look at the birch pollen from different angles and summarize current knowledge on internal and external influences that have an impact on the allergenicity of birch pollen and its interactions with the epithelial barrier. We focus on epithelial cells since these cells are the first line of defense in respiratory disease and are increasingly considered to be a regulatory tissue for the protection against the development of respiratory allergies.
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Involvement and therapeutic implications of airway epithelial barrier dysfunction in type 2 inflammation of asthma. Chin Med J (Engl) 2022; 135:519-531. [PMID: 35170505 PMCID: PMC8920422 DOI: 10.1097/cm9.0000000000001983] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Type 2 inflammation is a complex immune response and primary mechanism for several common allergic diseases including allergic rhinitis, allergic asthma, atopic dermatitis, and chronic rhinosinusitis with nasal polyps. It is the predominant type of immune response against helminths to prevent their tissue infiltration and induce their expulsion. Recent studies suggest that epithelial barrier dysfunction contributes to the development of type 2 inflammation in asthma, which may partly explain the increasing prevalence of asthma in China and around the globe. The epithelial barrier hypothesis has recently been proposed and has received great interest from the scientific community. The development of leaky epithelial barriers leads to microbial dysbiosis and the translocation of bacteria to inter- and sub-epithelial areas and the development of epithelial tissue inflammation. Accordingly, preventing the impairment and promoting the restoration of a deteriorated airway epithelial barrier represents a promising strategy for the treatment of asthma. This review introduces the interaction between type 2 inflammation and the airway epithelial barrier in asthma, the structure and molecular composition of the airway epithelial barrier, and the assessment of epithelial barrier integrity. The role of airway epithelial barrier disruption in the pathogenesis of asthma will be discussed. In addition, the possible mechanisms underlying the airway epithelial barrier dysfunction induced by allergens and environmental pollutants, and current treatments to restore the airway epithelial barrier are reviewed.
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Tripathi A, Hazari PP, Mishra AK, Kumar B, Sagi SSK. Quercetin: a savior of alveolar barrier integrity under hypoxic microenvironment. Tissue Barriers 2021; 9:1883963. [PMID: 33632082 DOI: 10.1080/21688370.2021.1883963] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
High altitude pulmonary edema (HAPE) is generally characterized by the loss of alveolar epithelial barrier integrity. The current study was undertaken to assess the noninvasive approaches of HAPE diagnosis and to evaluate the prophylactic potential of quercetin in preventing alveolar junction impairments. Male SD rats fed with quercetin 1 h prior to hypoxia (7,620 m, for 6 h) were selected. PET/CT imaging was performed to visualize the lung uptake of 18F-FDG in animals under hypoxia. Further, oxidant status, catalase activity, hematological & blood gas parameters were evaluated. Moreover, tight junction (TJ) proteins (ZO-1, JAM-C, Claudin-4, and occludin) expression analysis was accomplished using immune-blotting. The structural differences in lung epithelia were noted by TEM imaging. Quercetin prophylaxis has significantly reduced the FDG uptake in rat lungs under hypoxia. It has also dramatically alleviated the protein oxidation followed by an elevation in catalase activity in the lungs under hypoxia. The TJ protein expression in the lungs has also been restored to normal upon quercetin pre-treatment. Concomitantly, the quercetin preconditioning has elicited the stable blood gas and hematological parameters under hypoxia. The observations from TEM imaging have also implicated the normal lung epithelial structures in the quercetin pretreated animals under hypoxia. Quercetin prophylaxis has significantly restored alveolar epithelium integrity by abating oxidative stress in the lungs under hypoxia.Abbreviations: CT- Computed Tomography18F-FDG- Fluorodeoxyglucose (18FHAPE- High Altitude Pulmonary EdemaHb- HemoglobinHCT- HematocritHCO3- BicarbonateJAM- Junctional Adhesion MoleculeKBq- Killo BecquerelPaO2- Partial pressure of arterial oxygenPaCO2- Partial pressure of arterial carbon di-oxidePET- Positron Emission TomographyRBC- Red Blood CorpusclesSD- Sprague DawleyTJ- Tight JunctionsTEM- Transmission Electron MicroscopyWBC- White Blood CorpusclesZO- Zona Occludin.
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Affiliation(s)
- Ankit Tripathi
- Hematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur Delhi-India
| | - Puja P Hazari
- Molecular Imaging and Research Centre, Institute of Nuclear Medicine and Allied Sciences, Delhi-India
| | - Anil K Mishra
- Molecular Imaging and Research Centre, Institute of Nuclear Medicine and Allied Sciences, Delhi-India
| | - Bhuvnesh Kumar
- Hematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur Delhi-India
| | - Sarada S K Sagi
- Hematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur Delhi-India
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Abstract
PURPOSE OF REVIEW This review summarizes recent progress in our understanding how environmental adjuvants promote the development of asthma. RECENT FINDINGS Asthma is a heterogeneous set of lung pathologies with overlapping features. Human studies and animal models suggest that exposure to different environmental adjuvants activate distinct immune pathways, which in turn give rise to distinct forms, or endotypes, of allergic asthma. Depending on their concentrations, inhaled TLR ligands can activate either type 2 inflammation, or Th17 differentiation, along with regulatory responses that function to attenuate inflammation. By contrast, a different category of environmental adjuvants, proteases, activate distinct immune pathways and prime predominantly type 2 immune responses. Asthma is not a single disease, but rather a group of pathologies with overlapping features. Different endotypes of asthma likely arise from perturbations of distinct immunologic pathways during allergic sensitization.
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Affiliation(s)
- Donald N Cook
- Immunogenetics Group, Immunity, Inflammation and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Dr., Research Triangle Park, Durham, NC, 27709, USA.
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M T, T A, B S, Ak G, Sks S. Curcumin prophylaxis refurbishes alveolar epithelial barrier integrity and alveolar fluid clearance under hypoxia. Respir Physiol Neurobiol 2019; 274:103336. [PMID: 31778793 DOI: 10.1016/j.resp.2019.103336] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/30/2019] [Accepted: 11/07/2019] [Indexed: 12/19/2022]
Abstract
We have studied the prophylactic efficacy of curcumin to ameliorate the impairment of tight junction protein integrity and fluid clearance in lungs of rats under hypoxia. A549 cells wereexposed to 3 % O2 for 1 h, 3 h, 6 h, 12 h, 24 h and 48 h and rats were exposed to 7620 m for 6 h. NF-κB, Hif-1α and their related genes, tight junction protein (TJ) (ZO-1, JAM-C, claudin-4 and claudin-5, claudin-18) expressions were determined in A549 cells and lungs of rats by western blotting, ELISA and their activity by reporter gene assay, siRNAp65 knock out. Tissue specific localization of tight junction protein was determined by immunohistochemistry and immunoflorescence. Further transmission electron microscopy (TEM) was used to visualize the TJ structures between pulmonary epithelial cells. Blood gas and hematological parameters were also assessed. Later we checked, whether prior treatment with curcumin can restore the altered alveolar epithelial barrier integrity that is compromised through inflammatory mediators under hypoxia, A549 cells were pre-treated (1 h) with 10 μM curcumin and rats with 50 mg curcumin/kg BW and exposed to hypoxia. Curcumin pre-treatment both in vitro and in vivo showed significant changes in TJ protein integrity, attenuated NF-κB activity with reduced expression of its regulatory genes in lung tissues, serum and bronchoalveolar lavage fluid (BALF) along with stabilized HIF-1α levels under hypoxia. NF-κB inhibitors MG132, SN50 or siRNA mediated p65 knock down significantly reduced the dextran FITC influx into the lungs. The present study indicates that, curcumin prophylaxis augments alveolar epithelial barrier integrity and alveolar fluid clearance under hypoxia.
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Affiliation(s)
- Titto M
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Ankit T
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Saumya B
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Gausal Ak
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
| | - Sarada Sks
- Haematology Division, Defence Institute of Physiology and Allied Sciences, Lucknow Road, Timarpur, Delhi 110054, India.
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Xu S, Xue X, You K, Fu J. Caveolin-1 regulates the expression of tight junction proteins during hyperoxia-induced pulmonary epithelial barrier breakdown. Respir Res 2016; 17:50. [PMID: 27176222 PMCID: PMC4866358 DOI: 10.1186/s12931-016-0364-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 04/25/2016] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Bronchopulmonary dysplasia (BPD) is a common complication in preterm infants that involves the downregulation of tight junction (TJ) proteins. However, the mechanism underlying downregulation of the expression of TJ proteins during at the early stages of hyperoxia-induced BPD remains to be understood. Here, we aimed to identify the role of caveolin-1 (Cav-1) in hyperoxia-induced pulmonary epithelial barrier breakdown. METHODS First, we established an in vitro pulmonary epithelial barrier models using primary type II alveolar epithelial cells (AEC-II) from newborn rats. AEC-II was assigned to the hyperoxic (85 % O2/5 % CO2) or normoxic (21 % O2/5 % CO2) groups. Second, AEC-II was transfected with Cav-1-siRNA to downregulate Cav-1 under normoxic exposure. Third, AEC-II was transfected with a cDNA encoding Cav-1 to upregulate Cav-1 expression under hyperoxic exposure. Then, expression levels of Cav-1 and TJ proteins were examined by immunofluorescence staining, reverse transcription-polymerase chain reaction, and Western blotting. The TJ structures visualized using a transmission electron microscope, and transepithelial resistance and apparent permeability coefficient of fluorescein isothiocyanate-dextran, which are indicators of barrier function, were measured. RESULTS Our data showed that exposure to hyperoxia disrupted the structure and function of the pulmonary epithelial barrier and decreased the ZO-1, occludin, claudin-4, and Cav-1 expression levels. Moreover, Cav-1 knockdown attenuated the expression of the other three genes and disrupted pulmonary epithelial barrier structure and function under normoxic exposure. However, Cav-1 upregulation markedly antagonized the hyperoxia-induced pulmonary epithelial barrier destruction and TJ protein loss. CONCLUSIONS This is the first study to present evidence illustrating the novel role of Cav-1 downregulation-mediated TJ protein loss in pulmonary epithelial barrier destruction during BPD.
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Affiliation(s)
- Shuyan Xu
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, 110004, Liaoning, China
| | - Xindong Xue
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, 110004, Liaoning, China
| | - Kai You
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, 110004, Liaoning, China
| | - Jianhua Fu
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, 110004, Liaoning, China.
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The Guinea Pig Sensitized by House Dust Mite: A Model of Experimental Cough Studies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 905:87-95. [DOI: 10.1007/5584_2016_217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Bernard A, Nickmilder M, Dumont X. Chlorinated pool attendance, airway epithelium defects and the risks of allergic diseases in adolescents: Interrelationships revealed by circulating biomarkers. ENVIRONMENTAL RESEARCH 2015; 140:119-26. [PMID: 25863185 DOI: 10.1016/j.envres.2015.03.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/09/2015] [Accepted: 03/30/2015] [Indexed: 05/26/2023]
Abstract
It has been suggested that allergic diseases might be epithelial disorders driven by various environmental stressors but the epidemiological evidence supporting this concept is limited. In a cross-sectional study of 835 school adolescents (365 boys; mean age, 15.5 yr), we measured the serum concentrations of Club cell protein (CC16), surfactant-associated protein D (SP-D) and of total and aeroallergen-specific IgE. We used the serum CC16/SP-D concentration ratio as an index integrating changes in the permeability (SP-D) and secretory function (CC16) of the airway epithelium. In both sexes, early swimming in chlorinated pools emerged as the most consistent and strongest predictor of low CC16 and CC16/SP-D ratio in serum. Among girls, a low CC16/SP-D ratio was associated with increased odds (lowest vs. highest tertile) for pet sensitization (OR 2.97, 95% CI 1.19-8.22) and for hay fever in subjects sensitized to pollen (OR 4.12, 95% CI 1.28-14.4). Among boys, a low CC16/SP-D ratio was associated with increased odds for house-dust mite (HDM) sensitization (OR 2.01, 95% CI 1.11-3.73), for allergic rhinitis in subjects sensitized to HDM (OR 3.52, 95% CI 1.22-11.1) and for asthma in subjects sensitized to any aeroallergen (OR 3.38, 95% CI 1.17-11.0), HDM (OR 5.20, 95% CI 1.40-24.2) or pollen (OR 5.82, 95% CI 1.51-27.4). Odds for allergic sensitization or rhinitis also increased with increasing SP-D or decreasing CC16 in serum. Our findings support the hypothesis linking the development of allergic diseases to epithelial barrier defects due to host factors or environmental stressors such as early swimming in chlorinated pools.
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Affiliation(s)
- Alfred Bernard
- Louvain Centre for Toxicology and Applied Pharmacology, Faculty of Medicine, Catholic University of Louvain, Brussels, Belgium.
| | - Marc Nickmilder
- Louvain Centre for Toxicology and Applied Pharmacology, Faculty of Medicine, Catholic University of Louvain, Brussels, Belgium
| | - Xavier Dumont
- Louvain Centre for Toxicology and Applied Pharmacology, Faculty of Medicine, Catholic University of Louvain, Brussels, Belgium
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Chapman DG, Tully JE, Nolin JD, Janssen-Heininger YM, Irvin CG. Animal models of allergic airways disease: where are we and where to next? J Cell Biochem 2015; 115:2055-64. [PMID: 25043224 DOI: 10.1002/jcb.24881] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 07/09/2014] [Indexed: 01/13/2023]
Abstract
In a complex inflammatory airways disease such as asthma, abnormalities in a plethora of molecular and cellular pathways ultimately culminate in characteristic impairments in respiratory function. The ability to study disease pathophysiology in the setting of a functioning immune and respiratory system therefore makes mouse models an invaluable tool in translational research. Despite the vast understanding of inflammatory airways diseases gained from mouse models to date, concern over the validity of mouse models continues to grow. Therefore the aim of this review is twofold; firstly, to evaluate mouse models of asthma in light of current clinical definitions, and secondly, to provide a framework by which mouse models can be continually refined so that they continue to stand at the forefront of translational science. Indeed, it is in viewing mouse models as a continual work in progress that we will be able to target our research to those patient populations in whom current therapies are insufficient.
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Affiliation(s)
- David G Chapman
- Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont; Woolcock Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
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Zeki AA, Bratt JM, Chang KY, Franzi LM, Ott S, Silveria M, Fiehn O, Last JA, Kenyon NJ. Intratracheal instillation of pravastatin for the treatment of murine allergic asthma: a lung-targeted approach to deliver statins. Physiol Rep 2015; 3:3/5/e12352. [PMID: 25969462 PMCID: PMC4463814 DOI: 10.14814/phy2.12352] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Systemic treatment with statins mitigates allergic airway inflammation, TH2 cytokine production, epithelial mucus production, and airway hyperreactivity (AHR) in murine models of asthma. We hypothesized that pravastatin delivered intratracheally would be quantifiable in lung tissues using mass spectrometry, achieve high drug concentrations in the lung with minimal systemic absorption, and mitigate airway inflammation and structural changes induced by ovalbumin. Male BALB/c mice were sensitized to ovalbumin (OVA) over 4 weeks, then exposed to 1% OVA aerosol or filtered air (FA) over 2 weeks. Mice received intratracheal instillations of pravastatin before and after each OVA exposure (30 mg/kg). Ultra performance liquid chromatography – mass spectrometry was used to quantify plasma, lung, and bronchoalveolar lavage fluid (BALF) pravastatin concentration. Pravastatin was quantifiable in mouse plasma, lung tissue, and BALF (BALF > lung > plasma for OVA and FA groups). At these concentrations pravastatin inhibited airway goblet cell hyperplasia/metaplasia, and reduced BALF levels of cytokines TNFα and KC, but did not reduce BALF total leukocyte or eosinophil cell counts. While pravastatin did not mitigate AHR, it did inhibit airway hypersensitivity (AHS). In this proof-of-principle study, using novel mass spectrometry methods we show that pravastatin is quantifiable in tissues, achieves high levels in mouse lungs with minimal systemic absorption, and mitigates some pathological features of allergic asthma. Inhaled pravastatin may be beneficial for the treatment of asthma by having direct airway effects independent of a potent anti-inflammatory effect. Statins with greater lipophilicity may achieve better anti-inflammatory effects warranting further research.
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Affiliation(s)
- Amir A Zeki
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
| | - Jennifer M Bratt
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
| | | | - Lisa M Franzi
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
| | - Sean Ott
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
| | - Mark Silveria
- U.C. Davis, West Coast Metabolomics Center (WCMC) University of California, Davis, California
| | - Oliver Fiehn
- U.C. Davis, West Coast Metabolomics Center (WCMC) University of California, Davis, California King Abdulaziz University, Biochemistry Department, Jeddah, Saudi Arabia
| | - Jerold A Last
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
| | - Nicholas J Kenyon
- University of California, Davis, California Department of Internal Medicine, University of California, Davis, California Division of Pulmonary, Critical Care and Sleep Medicine, University of California, Davis, California Center for Comparative Respiratory Biology and Medicine (CCRBM) University of California, Davis, California
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Zhuang J, Zhao L, Zang N, Xu F. Prenatal nicotinic exposure augments cardiorespiratory responses to activation of bronchopulmonary C-fibers. Am J Physiol Lung Cell Mol Physiol 2015; 308:L922-30. [PMID: 25747962 PMCID: PMC4421788 DOI: 10.1152/ajplung.00241.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 03/01/2015] [Indexed: 12/26/2022] Open
Abstract
Rat pups prenatally exposed to nicotine (PNE) present apneic (lethal ventilatory arrest) responses during severe hypoxia. To clarify whether these responses are of central origin, we tested PNE effects on ventilation and diaphragm electromyography (EMGdi) during hypoxia in conscious rat pups. PNE produced apnea (lethal ventilatory arrest) identical to EMGdi silencing during hypoxia, indicating a central origin of this apneic response. We further asked whether PNE would sensitize bronchopulmonary C-fibers (PCFs), a key player in generating central apnea, with increase of the density and transient receptor potential cation channel subfamily V member 1 (TRPV1) expression of C-fibers/neurons in the nodose/jugular (N/J) ganglia and neurotrophic factors in the airways and lungs. We compared 1) ventilatory and pulmonary C-neural responses to right atrial bolus injection of capsaicin (CAP, 0.5 μg/kg), 2) bronchial substance P-immunoreactive (SP-IR) fiber density, 3) gene and protein expressions of TRPV1 in the ganglia, and 4) nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) protein in bronchoalveolar lavage fluid (BALF) and TrkA and TrkB genes in the ganglia between control and PNE pups. PNE markedly strengthened the PCF-mediated apneic response to CAP via increasing pulmonary C-neural sensitivity. PNE also enhanced bronchial SP-IR fiber density and N/J ganglia neural TRPV1 expression associated with increased gene expression of TrkA in the N/G ganglia and decreased NGF and BDNF in BALF. Our results suggest that PNE enhances PCF sensitivity likely through increasing PCF density and TRPV1 expression via upregulation of neural TrkA and downregulation of pulmonary BDNF, which may contribute to the PNE-promoted central apnea (lethal ventilatory arrest) during hypoxia.
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Affiliation(s)
- Jianguo Zhuang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Lei Zhao
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Na Zang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Fadi Xu
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
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Robichaud A, Fereydoonzad L, Schuessler TF. Delivered dose estimate to standardize airway hyperresponsiveness assessment in mice. Am J Physiol Lung Cell Mol Physiol 2015; 308:L837-46. [PMID: 25637610 DOI: 10.1152/ajplung.00343.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/23/2015] [Indexed: 11/22/2022] Open
Abstract
Airway hyperresponsiveness often constitutes a primary outcome in respiratory studies in mice. The procedure commonly employs aerosolized challenges, and results are typically reported in terms of bronchoconstrictor concentrations loaded into the nebulizer. Yet, because protocols frequently differ across studies, especially in terms of aerosol generation and delivery, direct study comparisons are difficult. We hypothesized that protocol variations could lead to differences in aerosol delivery efficiency and, consequently, in the dose delivered to the subject, as well as in the response. Thirteen nebulization patterns containing common protocol variations (nebulization time, duty cycle, particle size spectrum, air humidity, and/or ventilation profile) and using increasing concentrations of methacholine and broadband forced oscillations (flexiVent, SCIREQ, Montreal, Qc, Canada) were created, characterized, and studied in anesthetized naïve A/J mice. A delivered dose estimate calculated from nebulizer-, ventilator-, and subject-specific characteristics was introduced and used to account for protocol variations. Results showed that nebulization protocol variations significantly affected the fraction of aerosol reaching the subject site and the delivered dose, as well as methacholine reactivity and sensitivity in mice. From the protocol variants studied, addition of a slow deep ventilation profile during nebulization was identified as a key factor for optimization of the technique. The study also highlighted sensitivity differences within the lung, as well as the possibility that airway responses could be selectively enhanced by adequate control of nebulizer and ventilator settings. Reporting results in terms of delivered doses represents an important standardizing element for assessment of airway hyperresponsiveness in mice.
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Affiliation(s)
- Annette Robichaud
- SCIREQ Scientific Respiratory Equipment, Inc., Montreal, Quebec, Canada
| | - Liah Fereydoonzad
- SCIREQ Scientific Respiratory Equipment, Inc., Montreal, Quebec, Canada
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13
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Gammon ST, Foje N, Brewer EM, Owers E, Downs CA, Budde MD, Leevy WM, Helms MN. Preclinical anatomical, molecular, and functional imaging of the lung with multiple modalities. Am J Physiol Lung Cell Mol Physiol 2014; 306:L897-914. [DOI: 10.1152/ajplung.00007.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In vivo imaging is an important tool for preclinical studies of lung function and disease. The widespread availability of multimodal animal imaging systems and the rapid rate of diagnostic contrast agent development have empowered researchers to noninvasively study lung function and pulmonary disorders. Investigators can identify, track, and quantify biological processes over time. In this review, we highlight the fundamental principles of bioluminescence, fluorescence, planar X-ray, X-ray computed tomography, magnetic resonance imaging, and nuclear imaging modalities (such as positron emission tomography and single photon emission computed tomography) that have been successfully employed for the study of lung function and pulmonary disorders in a preclinical setting. The major principles, benefits, and applications of each imaging modality and technology are reviewed. Limitations and the future prospective of multimodal imaging in pulmonary physiology are also discussed. In vivo imaging bridges molecular biological studies, drug design and discovery, and the imaging field with modern medical practice, and, as such, will continue to be a mainstay in biomedical research.
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Affiliation(s)
- Seth T. Gammon
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Nathan Foje
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Elizabeth M. Brewer
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
| | - Elizabeth Owers
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Charles A. Downs
- Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, Georgia; and
| | - Matthew D. Budde
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - W. Matthew Leevy
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - My N. Helms
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
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Sardella A, Voisin C, Dumont X, Marcucci F, Bernard A. Nasal epithelium biomarkers in young children: associations with allergic sensitization and environmental stressors. Pediatr Pulmonol 2013; 48:571-8. [PMID: 23169618 DOI: 10.1002/ppul.22717] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 10/02/2012] [Indexed: 11/09/2022]
Abstract
BACKGROUND Recent studies suggest that allergic diseases might have their onset in early epithelial barrier defects. To test this hypothesis, we assessed associations between nasal epithelium biomarkers, environmental stressors, and the risks of allergic sensitization. METHODS In a cross-sectional study of 288 kindergarten children (mean age, 5.7 years), we measured aeroallergen-specific IgE in nasal mucosa and the concentrations of urea, albumin, and Clara cell protein (CC16) in nasal lavage fluid (NALF). Albumin and CC16 in NALF were expressed per liter or as a ratio to urea. We also calculated the NALF CC16/albumin ratio as an index integrating the permeability and the secretory function of the nasal epithelium. RESULTS Median NALF concentrations of CC16 and albumin were 8.2 µg/L and 34.5 mg/L, respectively. While there were no significant gender differences when proteins were expressed per liter, the CC16 to albumin and CC16 to urea ratios in NALF were higher in girls than in boys (P = 0.02 and 0.055, respectively. The nasal epithelial barrier function, as reflected by these NALF biomarkers, was positively influenced by probiotics and age, and negatively by environmental stressors such as pool chlorine. The risk of house dust mite (HDM) sensitization increased with decreasing log NALF CC16 concentration, whether expressed per liter (2.59, 95% CI: 1.15-5.82, P = 0.02), as a ratio to urea (1.98, 95% CI: 0.96-4.06, P = 0.06), or as a ratio to albumin (OR, 2.03, 95% CI: 1.10-3.74, P = 0.02). Children in the highest and intermediate tertiles of the NALF albumin/urea ratio were three times more likely to be sensitized to HDM than those in the lowest tertile (both P = 0.04). CONCLUSION Defects in the nasal epithelium barrier function of young children, as reflected by the concentrations of CC16 and albumin in NALF, are associated with environmental factors, including pool chlorine, and with increased risks of HDM sensitization.
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Affiliation(s)
- Antonia Sardella
- Louvain Centre for Toxicology and Applied Pharmacology, Faculty of Medicine, Catholic University of Louvain, Brussels, Belgium
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Walker JKL, Kraft M, Fisher JT. Assessment of murine lung mechanics outcome measures: alignment with those made in asthmatics. Front Physiol 2013; 3:491. [PMID: 23408785 PMCID: PMC3569663 DOI: 10.3389/fphys.2012.00491] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 12/17/2012] [Indexed: 01/13/2023] Open
Abstract
Although asthma is characterized as an inflammatory disease, recent reports highlight the importance of pulmonary physiology outcome measures to the clinical assessment of asthma control and risk of asthma exacerbation. Murine models of allergic inflammatory airway disease have been widely used to gain mechanistic insight into the pathogenesis of asthma; however, several aspects of murine models could benefit from improvement. This review focuses on aligning lung mechanics measures made in mice with those made in humans, with an eye toward improving the translational utility of these measures. A brief description of techniques available to measure murine lung mechanics is provided along with a methodological consideration of their utilization. How murine lung mechanics outcome measures relate to pulmonary physiology measures conducted in humans is discussed and we recommend that, like human studies, outcome measures be standardized for murine models of asthma.
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Affiliation(s)
- Julia K L Walker
- Division of Pulmonary, Allergy and Critical Care Medicine, Duke University Medical Center Durham, NC, USA
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Morty RE, Matalon S. “Real-time visualization of lung function: from micro to macro”. Am J Physiol Lung Cell Mol Physiol 2013; 304:L1-3. [DOI: 10.1152/ajplung.00279.2012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Rory E. Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
- Department of Internal Medicine (Pulmonology), University Hospital Giessen and Marburg, Giessen, Germany; and
| | - Sadis Matalon
- Department of Anesthesiology, University of Alabama at Birmingham, Alabama
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Domnik NJ, Seaborn G, Vincent SG, Akl SG, Redfearn DP, Fisher JT. OVA-induced airway hyperresponsiveness alters murine heart rate variability and body temperature. Front Physiol 2012; 3:456. [PMID: 23227012 PMCID: PMC3514704 DOI: 10.3389/fphys.2012.00456] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 11/15/2012] [Indexed: 01/07/2023] Open
Abstract
Altered autonomic (ANS) tone in chronic respiratory disease is implicated as a factor in cardiovascular co-morbidities, yet no studies address its impact on cardiovascular function in the presence of murine allergic airway (AW) hyperresponsiveness (AHR). Since antigen (Ag)-induced AHR is used to model allergic asthma (in which ANS alterations have been reported), we performed a pilot study to assess measurement feasibility of, as well as the impact of allergic sensitization to ovalbumin (OVA) on, heart rate variability (HRV) in a murine model. Heart rate (HR), body temperature (TB), and time- and frequency-domain HRV analyses, a reflection of ANS control, were obtained in chronically instrumented mice (telemetry) before, during and for 22 h after OVA or saline aerosolization in sensitized (OVA) or Alum adjuvant control exposed animals. OVA mice diverged significantly from Alum mice with respect to change in HR during aerosol challenge (P < 0.001, Two-Way ANOVA; HR max change Ctrl = +80 ± 10 bpm vs. OVA = +1 ± 23 bpm, mean ± SEM), and displayed elevated HR during the subsequent dark cycle (P = 0.006). Sensitization decreased the TB during aerosol challenge (P < 0.001). Sensitized mice had decreased HRV prior to challenge (SDNN: P = 0.038; Low frequency (LF) power: P = 0.021; Low/high Frequency (HF) power: P = 0.042), and increased HRV during Ag challenge (RMSSD: P = 0.047; pNN6: P = 0.039). Sensitized mice displayed decreased HRV subsequent to OVA challenge, primarily in the dark cycle (RMSSD: P = 0.018; pNN6: P ≤ 0.001; LF: P ≤ 0.001; HF: P = 0.040; LF/HF: P ≤ 0.001). We conclude that implanted telemetry technology is an effective method to assess the ANS impact of allergic sensitization. Preliminary results show mild sensitization is associated with reduced HRV and a suppression of the acute TB-response to OVA challenge. This approach to assess altered ANS control in the acute OVA model may also be beneficial in chronic AHR models.
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Affiliation(s)
- N J Domnik
- Department of Biomedical and Molecular Sciences (Physiology Program), Queen's University Kingston, ON, Canada
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18
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Hansbro PM, Scott GV, Essilfie AT, Kim RY, Starkey MR, Nguyen DH, Allen PD, Kaiko GE, Yang M, Horvat JC, Foster PS. Th2 cytokine antagonists: potential treatments for severe asthma. Expert Opin Investig Drugs 2012; 22:49-69. [PMID: 23126660 DOI: 10.1517/13543784.2013.732997] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Asthma is a major disease burden worldwide. Treatment with steroids and long acting β-agonists effectively manage symptoms in many patients but do not treat the underlying cause of disease and have serious side effects when used long term and in children. Therapies targeting the underlying causes of asthma are urgently needed. T helper type 2 (Th2) cells and the cytokines they release are clinically linked to the presentation of all forms of asthma. They are the primary drivers of mild to moderate and allergic asthma. They also play a pathogenetic role in exacerbations and more severe asthma though other factors are also involved. Much effort using animal models and human studies has been dedicated to the identification of the pathogenetic roles of these cells and cytokines and whether inhibition of their activity has therapeutic benefit in asthma. AREAS COVERED We discuss the current status of Th2 cytokine antagonists for the treatment of asthma. We also discuss the potential for targeting Th2-inducing cytokines, Th2 cell receptors and signaling as well as the use of Th2 cell antagonists, small interfering oligonucleotides, microRNAs, and combination therapies. EXPERT OPINION Th2 antagonists may be most effective in particular asthma subtypes/endotypes where specific cytokines are known to be active through the analysis of biomarkers. Targeting common receptors and pathways used by these cytokines may have additional benefit. Animal models have been valuable in identifying therapeutic targets in asthma, however the results from such studies need to be carefully interpreted and applied to appropriately stratified patient cohorts in well-designed clinical studies and trials.
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Affiliation(s)
- Philip M Hansbro
- The University of Newcastle, Priority Research Centre for Asthma and Respiratory Disease and Hunter Medical Research Institute, Level 2, Kookaburra Circuit, New Lambton Heights, Newcastle, New South Wales, 2305, Australia.
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Roth HM, Wadsworth SJ, Kahn M, Knight DA. The airway epithelium in asthma: developmental issues that scar the airways for life? Pulm Pharmacol Ther 2012; 25:420-6. [PMID: 23022283 DOI: 10.1016/j.pupt.2012.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 08/19/2012] [Accepted: 09/11/2012] [Indexed: 11/30/2022]
Abstract
While allergies are very common, affecting ∼40% of the population in most Western countries, only a proportion of allergic people develop asthma. This highlights the importance of tissue and cell specific mechanisms that contribute to the disease. As the interface between the inhaled environment and the internal environment of the lung, the epithelium normally possesses numerous mechanisms to maintain an effective protective barrier. However, the inability of the airway epithelium of asthmatics to effectively defend the lung against normally innocuous inhaled agents strongly suggests that asthma must involve defects in the epithelial barrier rather than being primarily an allergic disease. Evidence is accumulating that in asthma, the epithelium does not go through normal stages of development and differentiation and as a consequence, remain somewhat "immature". This in turn leads to a chronic cycle of dysregulated damage and repair which ultimately impacts on the airways function by increasing inflammation, but also by initiating processes that ultimately lead to changes to the structure and function of the airway.
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Affiliation(s)
- Hollis M Roth
- UBC James Hogg Research Centre, Institute for Heart + Lung Health, Canada
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20
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Llanora GV, Ming LJ, Wei LM, van Bever HP. House dust mite sensitization in toddlers predict persistent wheeze in children between eight to fourteen years old. Asia Pac Allergy 2012; 2:181-6. [PMID: 22872820 PMCID: PMC3406297 DOI: 10.5415/apallergy.2012.2.3.181] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Accepted: 07/02/2012] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Identifying toddlers at increased risk of developing persistent wheeze provides an opportunity for risk-reducing interventions. House dust mite (HDM) allergen sensitization might identify this group of high-risk children. OBJECTIVE We examined whether a positive skin prick test (SPT) to at least 1 of the 3 HDMs in wheezing toddlers, would serve as a predictor for persistent wheeze at age 8 to 14 years old. METHODS A cohort of 78 children, who had wheezing episodes, and underwent SPT to 3 HDMs between the ages of 2 to 5 years old, were enrolled. SPT results were obtained from the National University Hospital database. Four to 9 years later, the children, currently between 8 to 14 years old, were re-assessed for persistence of asthma symptoms and other atopic disorders via a telephone interview. A validated questionnaire on current wheezing and asthma, developed by the International Study of Asthma and Allergies in Childhood, was used. Fisher's exact test was used to evaluate the association between persistence of asthma and a positive SPT. RESULTS Of the 78 children who participated in the study, 42 (53.8%) had a positive SPT and 36 (46.2%) had a negative SPT. Of these, 18 (42.9%) of SPT positive and 7 (19.4%) of SPT negative children had persistence of asthma symptoms. There is a significant association between a positive SPT during the preschool years, and persistence of asthma (p = 0.0314 [<0.05]). CONCLUSION HDM sensitization at ages 2 to 5 years old in wheezing children predicts persistence of asthma after 4 to 9 years. This in turn may have benefits for management of asthma in this high-risk group.
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Affiliation(s)
- Genevieve V Llanora
- Department of Paediatrics, National University Hospital Singapore, Singapore 119228, Singapore
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Orchestrating house dust mite-associated allergy in the lung. Trends Immunol 2011; 32:402-11. [PMID: 21783420 DOI: 10.1016/j.it.2011.06.006] [Citation(s) in RCA: 303] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 05/21/2011] [Accepted: 06/16/2011] [Indexed: 12/14/2022]
Abstract
House dust mites (HDM; Dermatophagoides sp.) are one of the commonest aeroallergens worldwide and up to 85% of asthmatics are typically HDM allergic. Allergenicity is associated both with the mites themselves and with ligands derived from mite-associated bacterial and fungal products. Murine models of allergic airways disease for asthma research have recently switched from the use of surrogate allergen ovalbumin together with adjuvant to use of the HDM extract. This has accelerated understanding of how adaptive and innate immunity generate downstream pathology. We review the myriad ways in which HDM allergic responses are orchestrated. Understanding the molecular pathways that elicit HDM-associated pathology is likely to reveal novel targets for therapeutic intervention.
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Mattila P, Joenväärä S, Renkonen J, Toppila-Salmi S, Renkonen R. Allergy as an epithelial barrier disease. Clin Transl Allergy 2011; 1:5. [PMID: 22410284 PMCID: PMC3294629 DOI: 10.1186/2045-7022-1-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 06/10/2011] [Indexed: 02/06/2023] Open
Abstract
The objective of this review is to focus on putative modified epithelial functions related to allergy. The dysregulation of the epithelial barrier might result in the allergen uptake, which could be the primary defect in the pathogenesis of allergic reaction. We review the literature of the role of respiratory epithelium as an active barrier, how allergens are transported through it and how it senses the hostile environmental allergens and other dangerous stimuli.
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Affiliation(s)
- Pirkko Mattila
- Transplantation Laboratory & Infection Biology Research Program, Haartman Institute, University of Helsinki & Helsinki University Central Hospital, HUSLAB, Helsinki, Finland.
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