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Landwehr KR, Mead-Hunter R, O'Leary RA, Kicic A, Mullins BJ, Larcombe AN. The respiratory health effects of acute in vivo diesel and biodiesel exhaust in a mouse model. CHEMOSPHERE 2024; 362:142621. [PMID: 38880256 DOI: 10.1016/j.chemosphere.2024.142621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/28/2024] [Accepted: 06/14/2024] [Indexed: 06/18/2024]
Abstract
BACKGROUND Biodiesel, a renewable diesel fuel that can be created from almost any natural fat or oil, is promoted as a greener and healthier alternative to commercial mineral diesel without the supporting experimental data to back these claims. The aim of this research was to assess the health effects of acute exposure to two types of biodiesel exhaust, or mineral diesel exhaust or air as a control in mice. Male BALB/c mice were exposed for 2-hrs to diluted exhaust obtained from a diesel engine running on mineral diesel, Tallow biodiesel or Canola biodiesel. A room air exposure group was used as a control. Twenty-four hours after exposure, a variety of respiratory related end point measurements were assessed, including lung function, responsiveness to methacholine and airway and systemic immune responses. RESULTS Tallow biodiesel exhaust exposure resulted in the greatest number of significant effects compared to Air controls, including increased airway hyperresponsiveness (178.1 ± 31.3% increase from saline for Tallow biodiesel exhaust exposed mice compared to 155.8 ± 19.1 for Air control), increased airway inflammation (63463 ± 13497 cells/mL in the bronchoalveolar lavage of Tallow biodiesel exhaust exposed mice compared to 40561 ± 11800 for Air exposed controls) and indications of immune dysregulation. In contrast, exposure to Canola biodiesel exhaust resulted in fewer significant effects compared to Air controls with a slight increase in airway resistance at functional residual capacity and indications of immune dysregulation. Exposure to mineral diesel exhaust resulted in significant effects between that of the two biodiesels with increased airway hyperresponsiveness and indications of immune dysregulation. CONCLUSION These data show that a single, brief exposure to biodiesel exhaust can result in negative health impacts in a mouse model, and that the biological effects of exposure change depending on the feedstock used to make the biodiesel.
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Affiliation(s)
- Katherine R Landwehr
- Occupation, Environment and Safety, School of Population Health, Curtin University, P.O. Box U1987, Perth, WA, 6845, Australia; Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA, 6009, Australia.
| | - Ryan Mead-Hunter
- Occupation, Environment and Safety, School of Population Health, Curtin University, P.O. Box U1987, Perth, WA, 6845, Australia
| | - Rebecca A O'Leary
- Department of Primary Industries and Regional Development, Perth, WA, 6151, Australia
| | - Anthony Kicic
- Occupation, Environment and Safety, School of Population Health, Curtin University, P.O. Box U1987, Perth, WA, 6845, Australia; Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA, 6009, Australia; Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Nedlands, Perth, WA, 6009, Australia; Centre for Cell Therapy and Regenerative Medicine, The University of Western Australia, Perth, WA, 6009, Australia
| | - Benjamin J Mullins
- Occupation, Environment and Safety, School of Population Health, Curtin University, P.O. Box U1987, Perth, WA, 6845, Australia
| | - Alexander N Larcombe
- Occupation, Environment and Safety, School of Population Health, Curtin University, P.O. Box U1987, Perth, WA, 6845, Australia; Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA, 6009, Australia
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Paget TL, Larcombe AN, Pinniger GJ, Tsioutsias I, Schneider JP, Parkinson-Lawrence EJ, Orgeig S. Mucopolysaccharidosis (MPS IIIA) mice have increased lung compliance and airway resistance, decreased diaphragm strength, and no change in alveolar structure. Am J Physiol Lung Cell Mol Physiol 2024; 326:L713-L726. [PMID: 38469649 DOI: 10.1152/ajplung.00445.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 12/18/2023] [Accepted: 01/18/2024] [Indexed: 03/13/2024] Open
Abstract
Mucopolysaccharidosis type IIIA (MPS IIIA) is characterized by neurological and skeletal pathologies caused by reduced activity of the lysosomal hydrolase, sulfamidase, and the subsequent primary accumulation of undegraded heparan sulfate (HS). Respiratory pathology is considered secondary in MPS IIIA and the mechanisms are not well understood. Changes in the amount, metabolism, and function of pulmonary surfactant, the substance that regulates alveolar interfacial surface tension and modulates lung compliance and elastance, have been reported in MPS IIIA mice. Here we investigated changes in lung function in 20-wk-old control and MPS IIIA mice with a closed and open thoracic cage, diaphragm contractile properties, and potential parenchymal remodeling. MPS IIIA mice had increased compliance and airway resistance and reduced tissue damping and elastance compared with control mice. The chest wall impacted lung function as observed by an increase in airway resistance and a decrease in peripheral energy dissipation in the open compared with the closed thoracic cage state in MPS IIIA mice. Diaphragm contractile forces showed a decrease in peak twitch force, maximum specific force, and the force-frequency relationship but no change in muscle fiber cross-sectional area in MPS IIIA mice compared with control mice. Design-based stereology did not reveal any parenchymal remodeling or destruction of alveolar septa in the MPS IIIA mouse lung. In conclusion, the increased storage of HS which leads to biochemical and biophysical changes in pulmonary surfactant also affects lung and diaphragm function, but has no impact on lung or diaphragm structure at this stage of the disease.NEW & NOTEWORTHY Heparan sulfate storage in the lungs of mucopolysaccharidosis type IIIA (MPS IIIA) mice leads to changes in lung function consistent with those of an obstructive lung disease and includes an increase in lung compliance and airway resistance and a decrease in tissue elastance. In addition, diaphragm muscle contractile strength is reduced, potentially further contributing to lung function impairment. However, no changes in parenchymal lung structure were observed in mice at 20 wk of age.
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Affiliation(s)
- Tamara L Paget
- Mechanisms in Cell Biology and Diseases Research Concentration, Clinical & Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Alexander N Larcombe
- Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth, Western Australia, Australia
- Occupation, Environment & Safety, School of Population Health, Curtin University, Perth, Western Australia, Australia
| | - Gavin J Pinniger
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Irene Tsioutsias
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
| | - Jan Philipp Schneider
- Hannover Medical School, Institute of Functional and Applied Anatomy, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
| | - Emma J Parkinson-Lawrence
- Mechanisms in Cell Biology and Diseases Research Concentration, Clinical & Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Sandra Orgeig
- Mechanisms in Cell Biology and Diseases Research Concentration, Clinical & Health Sciences, University of South Australia, Adelaide, South Australia, Australia
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Landwehr KR, Mead-Hunter R, O'Leary RA, Kicic A, Mullins BJ, Larcombe AN. Respiratory Health Effects of In Vivo Sub-Chronic Diesel and Biodiesel Exhaust Exposure. Int J Mol Sci 2023; 24:ijms24065130. [PMID: 36982203 PMCID: PMC10049281 DOI: 10.3390/ijms24065130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/01/2023] [Accepted: 03/03/2023] [Indexed: 03/30/2023] Open
Abstract
Biodiesel, which can be made from a variety of natural oils, is currently promoted as a sustainable, healthier replacement for commercial mineral diesel despite little experimental data supporting this. The aim of our research was to investigate the health impacts of exposure to exhaust generated by the combustion of diesel and two different biodiesels. Male BALB/c mice (n = 24 per group) were exposed for 2 h/day for 8 days to diluted exhaust from a diesel engine running on ultra-low sulfur diesel (ULSD) or Tallow or Canola biodiesel, with room air exposures used as control. A variety of respiratory-related end-point measurements were assessed, including lung function, responsiveness to methacholine, airway inflammation and cytokine response, and airway morphometry. Exposure to Tallow biodiesel exhaust resulted in the most significant health impacts compared to Air controls, including increased airway hyperresponsiveness and airway inflammation. In contrast, exposure to Canola biodiesel exhaust resulted in fewer negative health effects. Exposure to ULSD resulted in health impacts between those of the two biodiesels. The health effects of biodiesel exhaust exposure vary depending on the feedstock used to make the fuel.
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Affiliation(s)
- Katherine R Landwehr
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth, WA 6845, Australia
- Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA 6009, Australia
| | - Ryan Mead-Hunter
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth, WA 6845, Australia
| | - Rebecca A O'Leary
- Department of Primary Industries and Regional Development, Perth, WA 6151, Australia
| | - Anthony Kicic
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth, WA 6845, Australia
- Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA 6009, Australia
- Department of Respiratory and Sleep Medicine, Perth Children's Hospital, Nedlands, Perth, WA 6009, Australia
- Centre for Cell Therapy and Regenerative Medicine, The University of Western Australia, Perth, WA 6009, Australia
| | - Benjamin J Mullins
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth, WA 6845, Australia
| | - Alexander N Larcombe
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth, WA 6845, Australia
- Respiratory Environmental Health, Wal-yan Respiratory Research Centre, Telethon Kids Institute, Perth Children's Hospital, Nedlands, Perth, WA 6009, Australia
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Respiratory mechanics during methacholine bolus and continuous infusion protocols in asthma model. Respir Physiol Neurobiol 2021; 292:103705. [PMID: 34062282 DOI: 10.1016/j.resp.2021.103705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 11/22/2022]
Abstract
Balb/c mice respiratory mechanics was studied in two intravenous methacholine (MCh) protocols: bolus and continuous infusion. The Constant Phase Model (CPM) was used in this study. The harmonic distortion index (kd) was used to assess the respiratory system nonlinearity. The analysis of variance showed difference between groups (OVA vs control) and among doses for both protocols. Bolus protocol posttest: there was a difference between OVA and control at 0.3 and 1 mg/kg doses (p<0.0001 and p<0.001) for Rn. Infusion: there was a difference between OVA and control at 192 μg.kg-1.min-1 dose for Rn, G and H, (p<0.01; p<0.001; p<0.001). An increment was found in kd values near to the observed peak values in bolus protocol. The bolus protocol could better differentiate inflamed and non-inflamed airway resistance, whereas the differences between OVA and control in continuous infusion protocol were associated to airway- and, mainly, parenchyma-related parameters. Moreover, the bolus protocol presented a higher nonlinear degree compared to the infusion protocol.
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Islas-Weinstein L, Marquina-Castillo B, Mata-Espinosa D, Paredes-González IS, Chávez J, Balboa L, Marín Franco JL, Guerrero-Romero D, Barrios-Payan JA, Hernandez-Pando R. The Cholinergic System Contributes to the Immunopathological Progression of Experimental Pulmonary Tuberculosis. Front Immunol 2021; 11:581911. [PMID: 33679685 PMCID: PMC7930380 DOI: 10.3389/fimmu.2020.581911] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 12/22/2020] [Indexed: 01/08/2023] Open
Abstract
The cholinergic system is present in both bacteria and mammals and regulates inflammation during bacterial respiratory infections through neuronal and non-neuronal production of acetylcholine (ACh) and its receptors. However, the presence of this system during the immunopathogenesis of pulmonary tuberculosis (TB) in vivo and in its causative agent Mycobacterium tuberculosis (Mtb) has not been studied. Therefore, we used an experimental model of progressive pulmonary TB in BALB/c mice to quantify pulmonary ACh using high-performance liquid chromatography during the course of the disease. In addition, we performed immunohistochemistry in lung tissue to determine the cellular expression of cholinergic system components, and then administered nicotinic receptor (nAChR) antagonists to validate their effect on lung bacterial burden, inflammation, and pro-inflammatory cytokines. Finally, we subjected Mtb cultures to colorimetric analysis to reveal the production of ACh and the effect of ACh and nAChR antagonists on Mtb growth. Our results show high concentrations of ACh and expression of its synthesizing enzyme choline acetyltransferase (ChAT) during early infection in lung epithelial cells and macrophages. During late progressive TB, lung ACh upregulation was even higher and coincided with ChAT and α7 nAChR subunit expression in immune cells. Moreover, the administration of nAChR antagonists increased pro-inflammatory cytokines, reduced bacillary loads and synergized with antibiotic therapy in multidrug resistant TB. Finally, in vitro studies revealed that the bacteria is capable of producing nanomolar concentrations of ACh in liquid culture. In addition, the administration of ACh and nicotinic antagonists to Mtb cultures induced or inhibited bacterial proliferation, respectively. These results suggest that Mtb possesses a cholinergic system and upregulates the lung non-neuronal cholinergic system, particularly during late progressive TB. The upregulation of the cholinergic system during infection could aid both bacterial growth and immunomodulation within the lung to favor disease progression. Furthermore, the therapeutic efficacy of modulating this system suggests that it could be a target for treating the disease.
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Affiliation(s)
- Leon Islas-Weinstein
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
| | - Brenda Marquina-Castillo
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
| | - Dulce Mata-Espinosa
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
| | - Iris S. Paredes-González
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
| | - Jaime Chávez
- Department of Bronchial Hyperreactivity, National Institute of Respiratory Diseases (Mexico), Mexico City, Mexico
| | - Luciana Balboa
- Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental del National Scientific and Technical Research Council (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - José Luis Marín Franco
- Laboratorio de Inmunología de Enfermedades Respiratorias, Instituto de Medicina Experimental del National Scientific and Technical Research Council (CONICET), Academia Nacional de Medicina, Buenos Aires, Argentina
| | - Daniel Guerrero-Romero
- Departamento de Matemáticas, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Jorge Alberto Barrios-Payan
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
| | - Rogelio Hernandez-Pando
- Division of Experimental Pathology, Department of Pathology, National Institute of Medical Sciences and Nutrition Salvador Zubirán, México City, Mexico
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Oliveira MA, Lino-Alvarado AE, Moriya HT, Vitorasso RL. Drug class effects on respiratory mechanics in animal models: access and applications. Exp Biol Med (Maywood) 2021; 246:1094-1103. [PMID: 33601911 DOI: 10.1177/1535370221993095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Assessment of respiratory mechanics extends from basic research and animal modeling to clinical applications in humans. However, to employ the applications in human models, it is desirable and sometimes mandatory to study non-human animals first. To acquire further precise and controlled signals and parameters, the animals studied must be further distant from their spontaneous ventilation. The majority of respiratory mechanics studies use positive pressure ventilation to model the respiratory system. In this scenario, a few drug categories become relevant: anesthetics, muscle blockers, bronchoconstrictors, and bronchodilators. Hence, the main objective of this study is to briefly review and discuss each drug category, and the impact of a drug on the assessment of respiratory mechanics. Before and during the positive pressure ventilation, the experimental animal must be appropriately sedated and anesthetized. The sedation will lower the pain and distress of the studied animal and the plane of anesthesia will prevent the pain. With those drugs, a more controlled procedure is carried out; further, because many anesthetics depress the respiratory system activity, a minimum interference of the animal's respiration efforts are achieved. The latter phenomenon is related to muscle blockers, which aim to minimize respiratory artifacts that may interfere with forced oscillation techniques. Generally, the respiratory mechanics are studied under appropriate anesthesia and muscle blockage. The application of bronchoconstrictors is prevalent in respiratory mechanics studies. To verify the differences among studied groups, it is often necessary to challenge the respiratory system, for example, by pharmacologically inducing bronchoconstriction. However, the selected bronchoconstrictor, doses, and administration can affect the evaluation of respiratory mechanics. Although not prevalent, studies have applied bronchodilators to return (airway resistance) to the basal state after bronchoconstriction. The drug categories can influence the mathematical modeling of the respiratory system, systemic conditions, and respiratory mechanics outcomes.
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Affiliation(s)
- Maria A Oliveira
- Department of Pharmacology, Institute of Biomedical Science, University of Sao Paulo (USP) Sao Paulo, SP 05508-000, Brazil
| | - Alembert E Lino-Alvarado
- Biomedical Engineering Laboratory - University of Sao Paulo (USP) Sao Paulo, SP 05508-010, Brazil
| | - Henrique T Moriya
- Biomedical Engineering Laboratory - University of Sao Paulo (USP) Sao Paulo, SP 05508-010, Brazil
| | - Renato L Vitorasso
- Biomedical Engineering Laboratory - University of Sao Paulo (USP) Sao Paulo, SP 05508-010, Brazil
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Vitorasso RDL, de Oliveira MA, Tavares-de-Lima W, Moriya HT. Respiratory mechanics evaluation of mice submitted to intravenous methacholine: Bolus vs. continuous infusion. Exp Biol Med (Maywood) 2020; 245:680-689. [PMID: 32183551 DOI: 10.1177/1535370220912393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
IMPACT STATEMENT Respiratory mechanics studies are associated with fundamental research and translational studies; the present work thus investigates this particular matter. Our current research describes differences and similarities between two different ways of administrating a very prevalent bronchoconstrictor (methacholine) in an aging process scenario. The core issue of our work is related with troubles we find with the bolus protocol and the application of the mathematical model used to assess the respiratory mechanics. Our findings reveal the continuous infusion as an alternative to these problems and we hope to provide the proper foundations to a more reliable assessment in the respiratory field.
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Affiliation(s)
- Renato de L Vitorasso
- Biomedical Engineering Laboratory, University of Sao Paulo (USP), Sao Paulo 05508-010, Brazil
| | - Maria A de Oliveira
- Department of Pharmacology, Institute of Biomedical Science USP, Sao Paulo 05508-000, Brazil
| | - Wothan Tavares-de-Lima
- Department of Pharmacology, Institute of Biomedical Science USP, Sao Paulo 05508-000, Brazil
| | - Henrique T Moriya
- Biomedical Engineering Laboratory, University of Sao Paulo (USP), Sao Paulo 05508-010, Brazil
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Bates JHT. CORP: Measurement of lung function in small animals. J Appl Physiol (1985) 2017; 123:1039-1046. [PMID: 28798197 DOI: 10.1152/japplphysiol.00243.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 08/02/2017] [Accepted: 08/02/2017] [Indexed: 11/22/2022] Open
Abstract
The measurement of lung function in mice and rats is crucial for understanding how well small animal models of pulmonary disease recapitulate human clinical pathology but brings with it the challenge of making accurate measurements in animals as small as a mouse. Overcoming these challenges can be achieved in a number of ways, each based on a model idealization of how the lung works as a mechanical system. Accordingly, it is important to understand the theoretical basis on which an assessment of lung function rests to interpret experimental measurements appropriately. It is also crucial to attend to a number of practical issues that determine the quality of the measurements. The most accurate measurements of lung function in small animals are provided by the forced oscillation technique that provides lung resistance and elastance and its multifrequency generalization known as impedance. Measurement quality is maximized when the greatest possible degree of control is exerted over the amplitude and frequency with which air is oscillated in and out of the lungs, the mean or end-expiratory transpulmonary pressure pertaining to when the oscillations are applied, and the immediate past volume history of the lungs. It is also crucial that no spontaneous breathing efforts occur during the measurement period. Finally, there is no substitute for the skill in animal handling and surgical preparation that comes with practice; such a skill should be in place before embarking on any important series of experiments.
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Affiliation(s)
- Jason H T Bates
- Department of Medicine, University of Vermont, Burlington, Vermont
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Larcombe AN, Janka MA, Mullins BJ, Berry LJ, Bredin A, Franklin PJ. The effects of electronic cigarette aerosol exposure on inflammation and lung function in mice. Am J Physiol Lung Cell Mol Physiol 2017; 313:L67-L79. [DOI: 10.1152/ajplung.00203.2016] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 03/24/2017] [Accepted: 03/28/2017] [Indexed: 11/22/2022] Open
Abstract
Electronic cigarette usage is increasing worldwide, yet there is a paucity of information on the respiratory health effects of electronic cigarette aerosol exposure. This study aimed to assess whether exposure to electronic cigarette (e-cigarette) aerosol would alter lung function and pulmonary inflammation in mice and to compare the severity of any alterations with mice exposed to mainstream tobacco smoke. Female BALB/c mice were exposed for 8 wk to tobacco smoke, medical air (control), or one of four different types of e-cigarette aerosol. E-cigarette aerosols varied depending on nicotine content (0 or 12 mg/ml) and the main excipient (propylene glycol or glycerin). Twenty-four hours after the final exposure, we measured pulmonary inflammation, lung volume, lung mechanics, and responsiveness to methacholine. Mice exposed to tobacco cigarette smoke had increased pulmonary inflammation and responsiveness to methacholine compared with air controls. Mice exposed to e-cigarette aerosol did not have increased inflammation but did display decrements in parenchymal lung function at both functional residual capacity and high transrespiratory pressures. Mice exposed to glycerin-based e-cigarette aerosols were also hyperresponsive to methacholine regardless of the presence or absence of nicotine. This study shows, for the first time, that exposure to e-cigarette aerosol during adolescence and early adulthood is not harmless to the lungs and can result in significant impairments in lung function.
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Affiliation(s)
- Alexander N. Larcombe
- Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia
- Health, Safety and Environment, School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Maxine A. Janka
- Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia
| | - Benjamin J. Mullins
- Fluid Dynamics Research Group, Curtin University, Perth, Western Australia, Australia
- Health, Safety and Environment, School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Luke J. Berry
- Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia
| | - Arne Bredin
- Fluid Dynamics Research Group, Curtin University, Perth, Western Australia, Australia
| | - Peter J. Franklin
- School of Population Health, University of Western Australia, Crawley, Western Australia, Australia; and
- Environmental Health Directorate, Department of Health, Shenton Park, Perth, Western Australia, Australia
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