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Friberg M, Behndig AF, Bosson JA, Muala A, Barath S, Dove R, Glencross D, Kelly FJ, Blomberg A, Mudway IS, Sandström T, Pourazar J. Human exposure to diesel exhaust induces CYP1A1 expression and AhR activation without a coordinated antioxidant response. Part Fibre Toxicol 2023; 20:47. [PMID: 38062420 PMCID: PMC10704793 DOI: 10.1186/s12989-023-00559-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 12/04/2023] [Indexed: 12/18/2023] Open
Abstract
BACKGROUND Diesel exhaust (DE) induces neutrophilia and lymphocytosis in experimentally exposed humans. These responses occur in parallel to nuclear migration of NF-κB and c-Jun, activation of mitogen activated protein kinases and increased production of inflammatory mediators. There remains uncertainty regarding the impact of DE on endogenous antioxidant and xenobiotic defences, mediated by nuclear factor erythroid 2-related factor 2 (Nrf2) and the aryl hydrocarbon receptor (AhR) respectively, and the extent to which cellular antioxidant adaptations protect against the adverse effects of DE. METHODS Using immunohistochemistry we investigated the nuclear localization of Nrf2 and AhR in the epithelium of endobronchial mucosal biopsies from healthy subjects six-hours post exposure to DE (PM10, 300 µg/m3) versus post-filtered air in a randomized double blind study, as a marker of activation. Cytoplasmic expression of cytochrome P450s, family 1, subfamily A, polypeptide 1 (CYP1A1) and subfamily B, Polypeptide 1 (CYP1B1) were examined to confirm AhR activation; with the expression of aldo-keto reductases (AKR1A1, AKR1C1 and AKR1C3), epoxide hydrolase and NAD(P)H dehydrogenase quinone 1 (NQO1) also quantified. Inflammatory and oxidative stress markers were examined to contextualize the responses observed. RESULTS DE exposure caused an influx of neutrophils to the bronchial airway surface (p = 0.013), as well as increased bronchial submucosal neutrophil (p < 0.001), lymphocyte (p = 0.007) and mast cell (p = 0.002) numbers. In addition, DE exposure enhanced the nuclear translocation of the AhR and increased the CYP1A1 expression in the bronchial epithelium (p = 0.001 and p = 0.028, respectively). Nuclear translocation of AhR was also increased in the submucosal leukocytes (p < 0.001). Epithelial nuclear AhR expression was negatively associated with bronchial submucosal CD3 numbers post DE (r = -0.706, p = 0.002). In contrast, DE did not increase nuclear translocation of Nrf2 and was associated with decreased NQO1 in bronchial epithelial cells (p = 0.02), without affecting CYP1B1, aldo-keto reductases, or epoxide hydrolase protein expression. CONCLUSION These in vivo human data confirm earlier cell and animal-based observations of the induction of the AhR and CYP1A1 by diesel exhaust. The induction of phase I xenobiotic response occurred in the absence of the induction of antioxidant or phase II xenobiotic defences at the investigated time point 6 h post-exposures. This suggests DE-associated compounds, such as polycyclic aromatic hydrocarbons (PAHs), may induce acute inflammation and alter detoxification enzymes without concomitant protective cellular adaptations in human airways.
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Affiliation(s)
- M Friberg
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - A F Behndig
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - J A Bosson
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Ala Muala
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - S Barath
- Department of Respiratory Medicine and Allergy, Lund University Hospital, Lund, Sweden
| | - R Dove
- Wolfson Institute for Population Health, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - D Glencross
- MRC Centre for Environment and Health, Imperial College London, London, UK
- NIHR Health Protection Research Unit in Environmental Exposures and Health, Imperial College London, London, UK
| | - F J Kelly
- MRC Centre for Environment and Health, Imperial College London, London, UK
- NIHR Health Protection Research Unit in Environmental Exposures and Health, Imperial College London, London, UK
| | - A Blomberg
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - I S Mudway
- MRC Centre for Environment and Health, Imperial College London, London, UK
- NIHR Health Protection Research Unit in Environmental Exposures and Health, Imperial College London, London, UK
| | - T Sandström
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - J Pourazar
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden.
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2
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Majumder N, Kodali V, Velayutham M, Goldsmith T, Amedro J, Khramtsov VV, Erdely A, Nurkiewicz TR, Harkema JR, Kelley EE, Hussain S. Aerosol physicochemical determinants of carbon black and ozone inhalation co-exposure induced pulmonary toxicity. Toxicol Sci 2023; 191:61-78. [PMID: 36303316 PMCID: PMC9887725 DOI: 10.1093/toxsci/kfac113] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Air pollution accounts for more than 7 million premature deaths worldwide. Using ultrafine carbon black (CB) and ozone (O3) as a model for an environmental co-exposure scenario, the dose response relationships in acute pulmonary injury and inflammation were determined by generating, characterizing, and comparing stable concentrations of CB aerosols (2.5, 5.0, 10.0 mg/m3), O3 (0.5, 1.0, 2.0 ppm) with mixture CB + O3 (2.5 + 0.5, 5.0 + 1.0, 10.0 + 2.0). C57BL6 male mice were exposed for 3 h by whole body inhalation and acute toxicity determined after 24 h. CB itself did not cause any alteration, however, a dose response in pulmonary injury/inflammation was observed with O3 and CB + O3. This increase in response with mixtures was not dependent on the uptake but was due to enhanced reactivity of the particles. Benchmark dose modeling showed several-fold increase in potency with CB + O3 compared with CB or O3 alone. Principal component analysis provided insight into response relationships between various doses and treatments. There was a significant correlation in lung responses with charge-based size distribution, total/alveolar deposition, oxidant generation, and antioxidant depletion potential. Lung tissue gene/protein response demonstrated distinct patterns that are better predicted by either particle dose/aerosol responses (interleukin-1β, keratinocyte chemoattractant, transforming growth factor beta) or particle reactivity (thymic stromal lymphopoietin, interleukin-13, interleukin-6). Hierarchical clustering showed a distinct signature with high dose and a similarity in mRNA expression pattern of low and medium doses of CB + O3. In conclusion, we demonstrate that the biological outcomes from CB + O3 co-exposure are significantly greater than individual exposures over a range of aerosol concentrations and aerosol characteristics can predict biological outcome.
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Affiliation(s)
- Nairrita Majumder
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Vamsi Kodali
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Morgantown, West Virginia 26508, USA
| | - Murugesan Velayutham
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Travis Goldsmith
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Jessica Amedro
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Valery V Khramtsov
- Department of Biochemistry and Molecular Medicine, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Aaron Erdely
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Morgantown, West Virginia 26508, USA
| | - Timothy R Nurkiewicz
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Morgantown, West Virginia 26508, USA
| | - Jack R Harkema
- Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan 48824, USA
| | - Eric E Kelley
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Morgantown, West Virginia 26508, USA
| | - Salik Hussain
- Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Center for Inhalation Toxicology (iTOX), School of Medicine, West Virginia University, Morgantown, West Virginia 26506, USA
- Health Effects Laboratory Division, National Institute for Occupational Safety and Health (NIOSH), Morgantown, West Virginia 26508, USA
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3
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Aghapour M, Ubags ND, Bruder D, Hiemstra PS, Sidhaye V, Rezaee F, Heijink IH. Role of air pollutants in airway epithelial barrier dysfunction in asthma and COPD. Eur Respir Rev 2022; 31:31/163/210112. [PMID: 35321933 PMCID: PMC9128841 DOI: 10.1183/16000617.0112-2021] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 11/13/2021] [Indexed: 12/12/2022] Open
Abstract
Chronic exposure to environmental pollutants is a major contributor to the development and progression of obstructive airway diseases, including asthma and COPD. Understanding the mechanisms underlying the development of obstructive lung diseases upon exposure to inhaled pollutants will lead to novel insights into the pathogenesis, prevention and treatment of these diseases. The respiratory epithelial lining forms a robust physicochemical barrier protecting the body from inhaled toxic particles and pathogens. Inhalation of airborne particles and gases may impair airway epithelial barrier function and subsequently lead to exaggerated inflammatory responses and airway remodelling, which are key features of asthma and COPD. In addition, air pollutant-induced airway epithelial barrier dysfunction may increase susceptibility to respiratory infections, thereby increasing the risk of exacerbations and thus triggering further inflammation. In this review, we discuss the molecular and immunological mechanisms involved in physical barrier disruption induced by major airborne pollutants and outline their implications in the pathogenesis of asthma and COPD. We further discuss the link between these pollutants and changes in the lung microbiome as a potential factor for aggravating airway diseases. Understanding these mechanisms may lead to identification of novel targets for therapeutic intervention to restore airway epithelial integrity in asthma and COPD. Exposure to air pollution induces airway epithelial barrier dysfunction through several mechanisms including increased oxidative stress, exaggerated cytokine responses and impaired host defence, which contributes to development of asthma and COPD. https://bit.ly/3DHL1CA
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Affiliation(s)
- Mahyar Aghapour
- Infection Immunology Group, Institute of Medical Microbiology, Infection Control and Prevention, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University, Magdeburg, Germany.,Immune Regulation Group, Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Niki D Ubags
- Faculty of Biology and Medicine, University of Lausanne, Service de Pneumologie, CHUV, Epalinges, Switzerland
| | - Dunja Bruder
- Infection Immunology Group, Institute of Medical Microbiology, Infection Control and Prevention, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University, Magdeburg, Germany.,Immune Regulation Group, Helmholtz Center for Infection Research, Braunschweig, Germany
| | - Pieter S Hiemstra
- Dept of Pulmonology, Leiden University Medical Center, Leiden, The Netherlands
| | - Venkataramana Sidhaye
- Pulmonary and Critical Care Medicine, Environmental Health and Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Fariba Rezaee
- Center for Pediatric Pulmonary Medicine, Cleveland Clinic Children's, Cleveland, OH, USA.,Dept of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Irene H Heijink
- University of Groningen, University Medical Center Groningen, Depts of Pathology and Medical Biology and Pulmonology, Groningen Research Institute for Asthma and COPD (GRIAC), Groningen, The Netherlands
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4
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Long E, Schwartz C, Carlsten C. Controlled human exposure to diesel exhaust: a method for understanding health effects of traffic-related air pollution. Part Fibre Toxicol 2022; 19:15. [PMID: 35216599 PMCID: PMC8876178 DOI: 10.1186/s12989-022-00454-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 02/03/2022] [Indexed: 12/17/2022] Open
Abstract
Diesel exhaust (DE) is a major component of air pollution in urban centers. Controlled human exposure (CHE) experiments are commonly used to investigate the acute effects of DE inhalation specifically and also as a paradigm for investigating responses to traffic-related air pollution (TRAP) more generally. Given the critical role this model plays in our understanding of TRAP’s health effects mechanistically and in support of associated policy and regulation, we review the methodology of CHE to DE (CHE–DE) in detail to distill critical elements so that the results of these studies can be understood in context. From 104 eligible publications, we identified 79 CHE–DE studies and extracted information on DE generation, exposure session characteristics, pollutant and particulate composition of exposures, and participant demographics. Virtually all studies had a crossover design, and most studies involved a single DE exposure per participant. Exposure sessions were typically 1 or 2 h in duration, with participants alternating between exercise and rest. Most CHE–DE targeted a PM concentration of 300 μg/m3. There was a wide range in commonly measured co-pollutants including nitrogen oxides, carbon monoxide, and total organic compounds. Reporting of detailed parameters of aerosol composition, including particle diameter, was inconsistent between studies, and older studies from a given lab were often cited in lieu of repeating measurements for new experiments. There was a male predominance in participants, and over half of studies involved healthy participants only. Other populations studied include those with asthma, atopy, or metabolic syndrome. Standardization in reporting exposure conditions, potentially using current versions of engines with modern emissions control technology, will allow for more valid comparisons between studies of CHE–DE, while recognizing that diesel engines in much of the world remain old and heterogeneous. Inclusion of female participants as well as populations more susceptible to TRAP will broaden the applicability of results from CHE–DE studies.
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Affiliation(s)
- Erin Long
- Faculty of Medicine, University of British Columbia, 317 - 2194 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Carley Schwartz
- Department of Medicine, Division of Respiratory Medicine, University of British Columbia, 2775 Laurel Street 7th Floor, Vancouver, BC, V5Z 1M9, Canada
| | - Christopher Carlsten
- Department of Medicine, Division of Respiratory Medicine, University of British Columbia, 2775 Laurel Street 7th Floor, Vancouver, BC, V5Z 1M9, Canada.
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5
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Long E, Carlsten C. Controlled human exposure to diesel exhaust: results illuminate health effects of traffic-related air pollution and inform future directions. Part Fibre Toxicol 2022; 19:11. [PMID: 35139881 PMCID: PMC8827176 DOI: 10.1186/s12989-022-00450-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/31/2022] [Indexed: 12/03/2022] Open
Abstract
Air pollution is an issue of increasing interest due to its globally relevant impacts on morbidity and mortality. Controlled human exposure (CHE) studies are often employed to investigate the impacts of pollution on human health, with diesel exhaust (DE) commonly used as a surrogate of traffic related air pollution (TRAP). This paper will review the results derived from 104 publications of CHE to DE (CHE-DE) with respect to health outcomes. CHE-DE studies have provided mechanistic evidence supporting TRAP’s detrimental effects on related to the cardiovascular system (e.g., vasomotor dysfunction, inhibition of fibrinolysis, and impaired cardiac function) and respiratory system (e.g., airway inflammation, increased airway responsiveness, and clinical symptoms of asthma). Oxidative stress is thought to be the primary mechanism of TRAP-induced effects and has been supported by several CHE-DE studies. A historical limitation of some air pollution research is consideration of TRAP (or its components) in isolation, limiting insight into the interactions between TRAP and other environmental factors often encountered in tandem. CHE-DE studies can help to shed light on complex conditions, and several have included co-exposure to common elements such as allergens, ozone, and activity level. The ability of filters to mitigate the adverse effects of DE, by limiting exposure to the particulate fraction of polluted aerosols, has also been examined. While various biomarkers of DE exposure have been evaluated in CHE-DE studies, a definitive such endpoint has yet to be identified. In spite of the above advantages, this paradigm for TRAP is constrained to acute exposures and can only be indirectly applied to chronic exposures, despite the critical real-world impact of living long-term with TRAP. Those with significant medical conditions are often excluded from CHE-DE studies and so results derived from healthy individuals may not apply to more susceptible populations whose further study is needed to avoid potentially misleading conclusions. In spite of limitations, the contributions of CHE-DE studies have greatly advanced current understanding of the health impacts associated with TRAP exposure, especially regarding mechanisms therein, with important implications for regulation and policy.
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Affiliation(s)
- Erin Long
- Faculty of Medicine, University of British Columbia, 317 - 2194 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Christopher Carlsten
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, 2775 Laurel Street 7th Floor, Vancouver, BC, V5Z 1M9, Canada.
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6
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Phillippi DT, Daniel S, Pusadkar V, Youngblood VL, Nguyen KN, Azad RK, McFarlin BK, Lund AK. Inhaled diesel exhaust particles result in microbiome-related systemic inflammation and altered cardiovascular disease biomarkers in C57Bl/6 male mice. Part Fibre Toxicol 2022; 19:10. [PMID: 35135577 PMCID: PMC8827295 DOI: 10.1186/s12989-022-00452-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/31/2022] [Indexed: 12/13/2022] Open
Abstract
Background The gut microbiota plays a vital role in host homeostasis and is associated with inflammation and cardiovascular disease (CVD) risk. Exposure to particulate matter (PM) is a known mediator of inflammation and CVD and is reported to promote dysbiosis and decreased intestinal integrity. However, the role of inhaled traffic-generated PM on the gut microbiome and its corresponding systemic effects are not well-characterized. Thus, we investigated the hypothesis that exposure to inhaled diesel exhaust particles (DEP) alters the gut microbiome and promotes microbial-related inflammation and CVD biomarkers. 4–6-week-old male C57Bl/6 mice on either a low-fat (LF, 10% fat) or high-fat (HF, 45% fat) diet were exposed via oropharyngeal aspiration to 35 μg DEP suspended in 35 μl saline or saline only (CON) 2x/week for 30 days. To determine whether probiotics could prevent diet or DEP exposure mediated alterations in the gut microbiome or systemic outcomes, a subset of animals on the HF diet were treated orally with 0.3 g/day (~ 7.5 × 108 CFU/day) of Winclove Ecologic® Barrier probiotics throughout the study. Results Our results show that inhaled DEP exposure alters gut microbial profiles, including reducing Actinobacteria and expanding Verrucomicrobia and Proteobacteria. We observed increased circulating LPS, altered circulating cytokines (IL-1α, IL-3, IL-13, IL-15, G-CSF, LIF, MIP-2, and TNF-α), and CVD biomarkers (siCAM, PAI-1, sP-Selectin, thrombomodulin, and PECAM) in DEP-exposed and/or HF diet mice. Furthermore, probiotics attenuated the observed reduction of Actinobacteria and expansion of Proteobacteria in DEP-exposed and HF-diet mice. Probiotics mitigated circulating cytokines (IL-3, IL-13, G-CSF, RANTES, and TNF- α) and CVD biomarkers (siCAM, PAI-1, sP-Selectin, thrombomodulin, and PECAM) in respect to DEP-exposure and/or HF diet. Conclusion Key findings of this study are that inhaled DEP exposure alters small intestinal microbial profiles that play a role in systemic inflammation and early CVD biomarkers. Probiotic treatment in this study was fundamental in understanding the role of inhaled DEP on the microbiome and related systemic inflammatory and CVD biomarkers. Supplementary Information The online version contains supplementary material available at 10.1186/s12989-022-00452-3.
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Affiliation(s)
- Danielle T Phillippi
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, EESAT - 215, 1704 W. Mulberry, Denton, TX, 76203, USA
| | - Sarah Daniel
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, EESAT - 215, 1704 W. Mulberry, Denton, TX, 76203, USA
| | - Vaidehi Pusadkar
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA
| | - Victoria L Youngblood
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, EESAT - 215, 1704 W. Mulberry, Denton, TX, 76203, USA
| | - Kayla N Nguyen
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, EESAT - 215, 1704 W. Mulberry, Denton, TX, 76203, USA
| | - Rajeev K Azad
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA.,Department of Mathematics, University of North Texas, Denton, TX, 76203, USA
| | - Brian K McFarlin
- Department of Biological Sciences, University of North Texas, Denton, TX, 76203, USA.,UNT Applied Physiology Laboratory, University of North Texas, Denton, TX, 76203, USA
| | - Amie K Lund
- Department of Biological Sciences, Advanced Environmental Research Institute, University of North Texas, EESAT - 215, 1704 W. Mulberry, Denton, TX, 76203, USA.
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Abstract
Rationale: Outdoor air pollution contributes to asthma development and exacerbations, yet its effects on airway pathology have not been defined in children. Objectives: To explore the possible link between air pollution and airway pathology, we retrospectively examined the relationship between environmental pollutants and pathological changes in bronchial biopsy specimens from children undergoing a clinically indicated bronchoscopy. Methods: Structural and inflammatory changes (basement membrane [BM] thickness, epithelial loss, eosinophils, neutrophils, macrophages, mast cells, and lymphocytes) were quantified in biopsy specimens by using immunohistochemistry. The association between exposure to particulate matter less than 10 μm in aerodynamic diameter (PM10), SO2 and NO2 and biopsy findings was evaluated by using a generalized additive model with Gamma family to allow for overdispersion, adjusted for atmospheric pressure, temperature, humidity, and wheezing. Results: Overall, 98 children were included (age 5.3 ± 2.9 yr; 53 with wheezing/45 without wheezing). BM thickness increased with prolonged exposure to PM10 (rate ratio [RR], 1.29; 95% confidence interval [CI], 1.09–1.52), particularly in children with wheezing. Prolonged exposure to PM10 was also associated with eosinophilic inflammation in children with wheezing (RR, 3.16; 95% CI, 1.35–7.39). Conversely, in children without wheezing, increased PM10 exposure was associated with a reduction of eosinophilic inflammation (RR, 0.12; 95% CI, 0.02–0.6) and neutrophilic inflammation (RR, 0.36; 95% CI, 0.14–0.89). Moreover, NO2 exposure was also linked to reductions in neutrophil infiltration (RR, 0.57; 95% CI, 0.34–0.93) and eosinophil infiltration (RR, 0.33; 95% CI, 0.14–0.77). Conclusions: Different patterns of association were observed in children with wheezing and in children without wheezing. In children without wheezing, exposure to PM10 and NO2 was linked to reduced eosinophilic and neutrophilic inflammation. Conversely, in children with wheezing, prolonged exposure to PM10 was associated with increased BM thickness and eosinophilic inflammation, suggesting that it might contribute to asthma development by promoting airway remodeling and inflammation.
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Kelly FJ, Fussell JC. Toxicity of airborne particles-established evidence, knowledge gaps and emerging areas of importance. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2020; 378:20190322. [PMID: 32981440 PMCID: PMC7536031 DOI: 10.1098/rsta.2019.0322] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/02/2020] [Indexed: 05/03/2023]
Abstract
Epidemiological research has taught us a great deal about the health effects of airborne particulate matter (PM), particularly cardiorespiratory effects of combustion-related particles. This has been matched by toxicological research to define underlying mechanistic pathways. To keep abreast of the substantial challenges that air pollution continues to throw at us requires yet more strides to be achieved. For example, being aware of the most toxic components/sources and having a definitive idea of the range of associated disease outcomes. This review discusses approaches designed to close some of these knowledge gaps. These include a focus on particles arising from non-exhaust PM at the roadside and microplastics-both of which are becoming more relevant in the light of a shift in PM composition in response to global pressure to reduce combustion emissions. The application of hypothesis-free approaches in both mechanistic studies and epidemiology in unveiling unexpected relationships and generating novel insights is also discussed. Previous work, strengthening the evidence for both the adverse effects and benefits of intervention tell us that the sooner we act to close knowledge gaps, increase awareness and develop creative solutions, the sooner we can reduce the public health burden attributable to these complex and insidious environmental pollutants. This article is part of a discussion meeting issue 'Air quality, past present and future'.
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Affiliation(s)
- Frank J. Kelly
- NIHR Health Protection Research Unit in Environmental Exposures and Health, School of Public Health, Imperial College London, Sir Michael Uren Building, White City Campus, 80-92 Wood Lane, London W12 0BZ, UK
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Miller MR, Poland CA. Nanotoxicology: The Need for a Human Touch? SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2001516. [PMID: 32697439 DOI: 10.1002/smll.202001516] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 04/28/2020] [Indexed: 06/11/2023]
Abstract
With the ever-expanding number of manufactured nanomaterials (MNMs) under development there is a vital need for nanotoxicology studies that test the potential for MNMs to cause harm to health. An extensive body of work in cell cultures and animal models is vital to understanding the physicochemical characteristics of MNMs and the biological mechanisms that underlie any detrimental actions to cells and organs. In human subjects, exposure monitoring is combined with measurement of selected health parameters in small panel studies, especially in occupational settings. However, the availability of further in vivo human data would greatly assist the risk assessment of MNMs. Here, the potential for controlled inhalation exposures of MNMs in human subjects is discussed. Controlled exposures to carbon, gold, aluminum, and zinc nanoparticles in humans have already set a precedence to demonstrate the feasibility of this approach. These studies have provided considerable insight into the potential (or not) of nanoparticles to induce inflammation, alter lung function, affect the vasculature, reach the systemic circulation, and accumulate in other organs. The need for further controlled exposures of MNMs in human volunteers - to establish no-effect limits, biological mechanisms, and provide vital data for the risk assessment of MNMs - is advocated.
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Affiliation(s)
- Mark R Miller
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Craig A Poland
- Centre for Inflammation Research, University of Edinburgh, Edinburgh, UK
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10
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Farcas MT, Stefaniak AB, Knepp AK, Bowers L, Mandler WK, Kashon M, Jackson SR, Stueckle TA, Sisler JD, Friend SA, Qi C, Hammond DR, Thomas TA, Matheson J, Castranova V, Qian Y. Acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) filaments three-dimensional (3-D) printer emissions-induced cell toxicity. Toxicol Lett 2019; 317:1-12. [PMID: 31562913 DOI: 10.1016/j.toxlet.2019.09.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 08/30/2019] [Accepted: 09/14/2019] [Indexed: 10/26/2022]
Abstract
During extrusion of some polymers, fused filament fabrication (FFF) 3-D printers emit billions of particles per minute and numerous organic compounds. The scope of this study was to evaluate FFF 3-D printer emission-induced toxicity in human small airway epithelial cells (SAEC). Emissions were generated from a commercially available 3-D printer inside a chamber, while operating for 1.5 h with acrylonitrile butadiene styrene (ABS) or polycarbonate (PC) filaments, and collected in cell culture medium. Characterization of the culture medium revealed that repeat print runs with an identical filament yield various amounts of particles and organic compounds. Mean particle sizes in cell culture medium were 201 ± 18 nm and 202 ± 8 nm for PC and ABS, respectively. At 24 h post-exposure, both PC and ABS emissions induced a dose dependent significant cytotoxicity, oxidative stress, apoptosis, necrosis, and production of pro-inflammatory cytokines and chemokines in SAEC. Though the emissions may not completely represent all possible exposure scenarios, this study indicate that the FFF could induce toxicological effects. Further studies are needed to quantify the detected chemicals in the emissions and their corresponding toxicological effects.
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Affiliation(s)
- Mariana T Farcas
- Pathology and Physiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA; Pharmaceutical and Pharmacological Sciences, School of Pharmacy, West Virginia University, Morgantown, WV, 26505, USA.
| | - Aleksandr B Stefaniak
- Field Studies Branch, Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Alycia K Knepp
- Field Studies Branch, Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Lauren Bowers
- Field Studies Branch, Respiratory Health Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - William K Mandler
- Pathology and Physiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Michael Kashon
- Biostatistics and Epidemiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Stephen R Jackson
- Exposure Assessment Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Todd A Stueckle
- Allergy and Clinical Immunology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Jenifer D Sisler
- Pathology and Physiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Sherri A Friend
- Pathology and Physiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
| | - Chaolong Qi
- Engineering and Physical Hazards Branch, Division of Applied Research & Technology, National Institute for Occupational Safety and Health, Cincinnati, OH, USA.
| | - Duane R Hammond
- Engineering and Physical Hazards Branch, Division of Applied Research & Technology, National Institute for Occupational Safety and Health, Cincinnati, OH, USA.
| | - Treye A Thomas
- Office of Hazard Identification and Reduction, U.S. Consumer Product Safety Commission, Rockville, MD, USA.
| | - Joanna Matheson
- Office of Hazard Identification and Reduction, U.S. Consumer Product Safety Commission, Rockville, MD, USA.
| | - Vincent Castranova
- Pharmaceutical and Pharmacological Sciences, School of Pharmacy, West Virginia University, Morgantown, WV, 26505, USA.
| | - Yong Qian
- Pathology and Physiology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA.
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11
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The Impact of Selected Biofuels on the Skoda Roomster 1.4TDI Engine’s Operational Parameters. ENERGIES 2019. [DOI: 10.3390/en12071388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Road transport is increasing all around the globe and biofuels have come to the forefront of public interest. According to Article 3, Directive 2009/28/EC, each member state has to ensure that an energy share from renewable sources in all forms of transportation reaches at least 10% of the final consumption of energy in transportation until 2020. The blending of biofuels is one of the methods available to member states to meet this target and it might even be expected to be a main contributor. This article analyses and compares selected biofuels, their chemical properties and their influence on engine operational parameters. The operational parameters of the diesel engine of the Skoda Roomster 1.4 TDI were measured on a chassis dynamometer according to the NEDC driving cycle, and pure diesel fuel, HVO and a blend of fuels (diesel fuel, HVO and butanol) were used for comparison. Operation on biofuels shows a slight decrease in performance parameters up to 10% and an increase in emission production (especially CO in the case of D50H30B20). Positive influences of biofuels were proven with a decrease in exhaust gas opacity and particulate matter production, up to 50% in the case of D50H30B20.
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12
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Yen YC, Yang CY, Mena KD, Cheng YT, Yuan CS, Chen PS. Jumping on the bed and associated increases of PM 10, PM 2.5, PM 1, airborne endotoxin, bacteria, and fungi concentrations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 245:799-809. [PMID: 30502709 DOI: 10.1016/j.envpol.2018.11.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 11/16/2018] [Accepted: 11/17/2018] [Indexed: 06/09/2023]
Abstract
Jumping on the bed is a favorite behavior of children; however, no study has investigated the increased air pollutants resulting from jumping on the bed. Therefore, we aimed to investigate the elevated concentrations of particulate matter (PM) and bioaerosols from jumping on the bed and making the bed. Simulation of jumping on the bed and making the bed was performed at sixty schoolchildren's houses in Taiwan. PM10, PM2.5, PM1 (PM with aerodynamic diameter less than 10, 2.5, and 1 μm, respectively) and airborne bacteria, fungi and endotoxin concentrations were simultaneously measured over simulation and background periods. Our results show the increase of PM10, PM2.5, PM1, airborne bacteria and fungi through the behavior of jumping on the bed (by 414 μg m-3, 353 μg m-3, 349 μg m-3, 6569 CFU m-3 and 978 CFU m-3, respectively). When making the bed, the PM10, PM2.5, PM1, airborne bacteria and fungi also significantly increased by 4.69 μg m-3, 4.09 μg m-3, 4.15 μg m-3, 8569 CFU m-3, and 779 CFU m-3, respectively. Airborne endotoxin concentrations significantly increased by 21.76 EU m-3 following jumping on the bed and making the bed. Moreover, when jumping on the bed, higher PM2.5 and PM1 concentrations in houses with furry pets rather than no furry pets, and less airborne fungi in apartments than in townhouses were found. For making the bed, lower airborne fungi was found in houses using essential oils rather than no essential oils using. The airborne endotoxin concentrations were positively associated with furry pets and smokers in the homes and negatively correlated to the home with window opening with a statistical significance during the periods of jumping on the bed and making the bed. In conclusion, significant increases of PM and bioaerosols during jumping on the bed and making the bed may need to be concerned.
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Affiliation(s)
- Yu-Chuan Yen
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung City, Taiwan
| | - Chun-Yuh Yang
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung City, Taiwan
| | - Kristina Dawn Mena
- Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, University of Texas Health Science Center at Houston, TX, United States
| | - Yu-Ting Cheng
- Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
| | - Chung-Shin Yuan
- Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Pei-Shih Chen
- Department of Public Health, College of Health Science, Kaohsiung Medical University, Kaohsiung City, Taiwan; Institute of Environmental Engineering, College of Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan; Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan.
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13
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Olvera Alvarez HA, Kubzansky LD, Campen MJ, Slavich GM. Early life stress, air pollution, inflammation, and disease: An integrative review and immunologic model of social-environmental adversity and lifespan health. Neurosci Biobehav Rev 2018; 92:226-242. [PMID: 29874545 PMCID: PMC6082389 DOI: 10.1016/j.neubiorev.2018.06.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 05/30/2018] [Accepted: 06/01/2018] [Indexed: 01/21/2023]
Abstract
Socially disadvantaged individuals are at greater risk for simultaneously being exposed to adverse social and environmental conditions. Although the mechanisms underlying joint effects remain unclear, one hypothesis is that toxic social and environmental exposures have synergistic effects on inflammatory processes that underlie the development of chronic diseases, including cardiovascular disease, diabetes, depression, and certain types of cancer. In the present review, we examine how exposure to two risk factors that commonly occur with social disadvantage-early life stress and air pollution-affect health. Specifically, we identify neuroimmunologic pathways that could link early life stress, inflammation, air pollution, and poor health, and use this information to propose an integrated, multi-level model that describes how these factors may interact and cause health disparity across individuals based on social disadvantage. This model highlights the importance of interdisciplinary research considering multiple exposures across domains and the potential for synergistic, cross-domain effects on health, and may help identify factors that could potentially be targeted to reduce disease risk and improve lifespan health.
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Affiliation(s)
- Hector A Olvera Alvarez
- School of Nursing, University of Texas at El Paso, Health Science and Nursing Building, Room 359, 500 West University Avenue, El Paso, TX, USA.
| | - Laura D Kubzansky
- Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Matthew J Campen
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM, USA
| | - George M Slavich
- Cousins Center for Psychoneuroimmunology and Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA, USA
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14
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Dai Y, Ren D, Bassig BA, Vermeulen R, Hu W, Niu Y, Duan H, Ye M, Meng T, Xu J, Bin P, Shen M, Yang J, Fu W, Meliefste K, Silverman D, Rothman N, Lan Q, Zheng Y. Occupational exposure to diesel engine exhaust and serum cytokine levels. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2018; 59:144-150. [PMID: 29023999 PMCID: PMC6438621 DOI: 10.1002/em.22142] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 09/05/2017] [Accepted: 09/07/2017] [Indexed: 05/27/2023]
Abstract
The International Agency for Research on Cancer has classified diesel engine exhaust (DEE) as a human lung carcinogen. Given that inflammation is suspected to be an important underlying mechanism of lung carcinogenesis, we evaluated the relationship between DEE exposure and the inflammatory response using data from a cross-sectional molecular epidemiology study of 41 diesel engine testing workers and 46 unexposed controls. Repeated personal exposure measurements of PM2.5 and other DEE constituents were taken for the diesel engine testing workers before blood collection. Serum levels of six inflammatory biomarkers including interleukin (IL)-1, IL-6, IL-8, tumor necrosis factor (TNF)-α, macrophage inflammatory protein (MIP)-1β, and monocyte chemotactic protein (MCP)-1 were analyzed in all subjects. Compared to unexposed controls, concentrations of MIP-1β were significantly reduced by ∼37% in DEE exposed workers (P < 0.001) and showed a strong decreasing trend with increasing PM2.5 concentrations in all subjects (Ptrend < 0.001) as well as in exposed subjects only (Ptrend = 0.001). Levels of IL-8 and MIP-1β were significantly lower in workers in the highest exposure tertile of PM2.5 (>397 µg/m3 ) compared to unexposed controls. Further, significant inverse exposure-response relationships for IL-8 and MCP-1 were also found in relation to increasing PM2.5 levels among the DEE exposed workers. Given that IL-8, MIP-1β, and MCP-1 are chemokines that play important roles in recruitment of immunocompetent cells for immune defense and tumor cell clearance, the observed lower levels of these markers with increasing PM2.5 exposure may provide insight into the mechanism by which DEE promotes lung cancer. Environ. Mol. Mutagen. 59:144-150, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Yufei Dai
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Dianzhi Ren
- Chaoyang Center for Disease Control and prevention, Chaoyang, China
| | - Bryan A. Bassig
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Roel Vermeulen
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Wei Hu
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Yong Niu
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Huawei Duan
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Meng Ye
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Tao Meng
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Jun Xu
- Hong Kong University, Hong Kong, China
| | - Ping Bin
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Meili Shen
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
| | - Jufang Yang
- Chaoyang Center for Disease Control and prevention, Chaoyang, China
| | - Wei Fu
- Chaoyang Center for Disease Control and prevention, Chaoyang, China
| | - Kees Meliefste
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Debra Silverman
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Nathaniel Rothman
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Qing Lan
- Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute. Rockville, Maryland, U.S.A
| | - Yuxin Zheng
- Key Laboratory of Chemical Safety and Health, National Institute for Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention. Beijing, China
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15
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Bassig BA, Dai Y, Vermeulen R, Ren D, Hu W, Duan H, Niu Y, Xu J, Shiels MS, Kemp TJ, Pinto LA, Fu W, Meliefste K, Zhou B, Yang J, Ye M, Jia X, Meng T, Wong JYY, Bin P, Hosgood HD, Hildesheim A, Silverman DT, Rothman N, Zheng Y, Lan Q. Occupational exposure to diesel engine exhaust and alterations in immune/inflammatory markers: a cross-sectional molecular epidemiology study in China. Carcinogenesis 2017; 38:1104-1111. [PMID: 28968774 PMCID: PMC5862277 DOI: 10.1093/carcin/bgx081] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 07/28/2017] [Indexed: 12/22/2022] Open
Abstract
The relationship between diesel engine exhaust (DEE), a known lung carcinogen, and immune/inflammatory markers that have been prospectively associated with lung cancer risk is not well understood. To provide insight into these associations, we conducted a cross-sectional molecular epidemiology study of 54 males highly occupationally exposed to DEE and 55 unexposed male controls from representative workplaces in China. We measured plasma levels of 64 immune/inflammatory markers in all subjects using Luminex bead-based assays, and compared our findings to those from a nested case-control study of these markers and lung cancer risk, which had been conducted among never-smoking women in Shanghai using the same multiplex panels. Levels of nine markers that were associated with lung cancer risk in the Shanghai study were altered in DEE-exposed workers in the same direction as the lung cancer associations. Among these, associations with the levels of CRP (β= -0.53; P = 0.01) and CCL15/MIP-1D (β = 0.20; P = 0.02) were observed in workers exposed to DEE and with increasing elemental carbon exposure levels (Ptrends <0.05) in multivariable linear regression models. Levels of a third marker positively associated with an increased lung cancer risk, CCL2/MCP-1, were higher among DEE-exposed workers compared with controls in never and former smokers, but not in current smokers (Pinteraction = 0.01). The immunological differences in these markers in DEE-exposed workers are consistent with associations observed for lung cancer risk in a prospective study of Chinese women and may provide some insight into the mechanistic processes by which DEE causes lung cancer.
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Affiliation(s)
- Bryan A Bassig
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Yufei Dai
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Roel Vermeulen
- Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Dianzhi Ren
- Chaoyang Center for Disease Control and Prevention, Chaoyang, Liaoning, China
| | - Wei Hu
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Huawei Duan
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Yong Niu
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Jun Xu
- Hong Kong University, Hong Kong, Hong Kong
| | - Meredith S Shiels
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Troy J Kemp
- HPV Immunology Laboratory, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Ligia A Pinto
- HPV Immunology Laboratory, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Wei Fu
- Chaoyang Center for Disease Control and Prevention, Chaoyang, Liaoning, China
| | - Kees Meliefste
- Division of Environmental Epidemiology, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Baosen Zhou
- China Medical University, Shenyang, Liaoning, China
| | - Jufang Yang
- Chaoyang Center for Disease Control and Prevention, Chaoyang, Liaoning, China
| | - Meng Ye
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Xiaowei Jia
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Tao Meng
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Jason YY Wong
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Ping Bin
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - H Dean Hosgood
- Division of Epidemiology, Albert Einstein College of Medicine, New York, NY, USA
| | - Allan Hildesheim
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Debra T Silverman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Nathaniel Rothman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
| | - Yuxin Zheng
- Key Laboratory of Chemical Safety and Health, National Institute of Occupational Health and Poison Control, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Qing Lan
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, DHHS, Rockville, MD, USA
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16
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Akopian AN, Fanick ER, Brooks EG. TRP channels and traffic-related environmental pollution-induced pulmonary disease. Semin Immunopathol 2016; 38:331-8. [PMID: 26837756 PMCID: PMC4896490 DOI: 10.1007/s00281-016-0554-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 01/19/2016] [Indexed: 12/21/2022]
Abstract
Environmental pollutant exposures are major risk factors for adverse health outcomes, with increased morbidity and mortality in humans. Diesel exhaust (DE) is one of the major harmful components of traffic-related air pollution. Exposure to DE affects several physiological systems, including the airways, and pulmonary diseases are increased in highly populated urban areas. Hence, there are urgent needs to (1) create newer and lesser polluting fuels, (2) improve exhaust aftertreatments and reduce emissions, and (3) understand mechanisms of actions for toxic effects of both conventional and cleaner diesel fuels on the lungs. These steps could aid the development of diagnostics and interventions to prevent the negative impact of traffic-related air pollution on the pulmonary system. Exhaust from conventional, and to a lesser extent, clean fuels, contains particulate matter (PM) and more than 400 additional chemical constituents. The major toxic constituents are nitrogen oxides (NOx) and polycyclic aromatic hydrocarbons (PAHs). PM and PAHs could potentially act via transient receptor potential (TRP) channels. In this review, we will first discuss the associations between DE from conventional as well as clean fuel technologies and acute and chronic airway inflammation. We will then review possible activation and/or potentiation of TRP vanilloid type 1 (TRPV1) and ankyrin 1 (TRPA1) channels by PM and PAHs. Finally, we will discuss and summarize recent findings on the mechanisms whereby TRPs could control the link between DE and airway inflammation, which is a primary determinant leading to pulmonary disease.
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Affiliation(s)
- Armen N Akopian
- Department of Endodontics, School of Dentistry, UT Health Science Center at San Antonio, San Antonio, TX, 78229, USA
| | - E Robert Fanick
- Office of Automotive Engineering, Southwest Research Institute, San Antonio, TX, 78228, USA
| | - Edward G Brooks
- Department of Pediatrics, Division of Immunology and Infectious Disease, School of Medicine, UT Health Science Center at San Antonio, San Antonio, TX, 78229, USA.
- Center for Airway Inflammation Research, UT Health Science Center at San Antonio, 8403 Floyd Curl Drive, STRF Microbiology MC 8259, San Antonio, TX, 78229, USA.
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17
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Dai Y, Zhang X, Zhang R, Zhao X, Duan H, Niu Y, Huang C, Meng T, Ye M, Bin P, Shen M, Jia X, Wang H, Yu S, Zheng Y. Long-term exposure to diesel engine exhaust affects cytokine expression among occupational population. Toxicol Res (Camb) 2016; 5:674-681. [PMID: 30090380 PMCID: PMC6060680 DOI: 10.1039/c5tx00462d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 01/31/2016] [Indexed: 11/21/2022] Open
Abstract
Diesel engine exhaust (DEE) is a predominant contributor to urban air pollution. The International Agency for Research on Cancer classified DEE as a group I carcinogen. Inflammatory response is considered to be associated with various health outcomes including carcinogenesis. However, human data linking inflammation with long-term DEE exposure are still lacking. In this study, a total of 137 diesel engine testing workers with an average exposure of 8.2 years and 108 unexposed controls were enrolled. Peripheral blood samples were collected from all subjects, and the association of DEE exposure with inflammatory biomarkers was analyzed. Overall, DEE exposed workers had a significant increase in the C-reactive protein (CRP) and a significant decrease in cytokines including interleukin (IL)-1β, IL-6, IL-8, and macrophage inflammatory protein (MIP)-1β compared to controls after adjusting for age, BMI, smoking status, and alcohol use, and findings were highly consistent when stratified by smoking status. In addition, exposure time dependent patterns for IL-6 and CRP were also found (Ptrend = 0.006 and 0.026, respectively); however, the levels of IL-1β and MIP-1β were significantly lower in subjects with a DEE working time of less than 10 years compared with the controls and then recovered to control levels in workers exposed for >10 years. There were no significant differences in blood cell counts and major lymphocyte subsets between exposed workers and the controls. Our results provide epidemiological evidence for the relationship between DEE exposure and immunotoxicity considering the important roles of cytokines in immunological processes.
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Affiliation(s)
- Yufei Dai
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Xiao Zhang
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Rong Zhang
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
- Department of Toxicology , School of Public Health , Hebei Medical University , Shijiazhuang , 050017 , China
| | - Xuezheng Zhao
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
- Beijing Xicheng District Tianqiao Community Health Service Center , Beijing , 100050 , China
| | - Huawei Duan
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Yong Niu
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Chuanfeng Huang
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Tao Meng
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Meng Ye
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Ping Bin
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Meili Shen
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
| | - Xiaowei Jia
- School and Hospital of Stomatology , Peking University , Beijing , 100081 , China
| | - Haisheng Wang
- Luoyang Center for Disease Control and Prevention , Luoyang , Henan Province 471000 , China
| | - Shanfa Yu
- Henan Provincial Institute for Occupational Health , Zhengzhou , 450052 , China
| | - Yuxin Zheng
- Key Laboratory of Chemical Safety and Health , National Institute for Occupational Health and Poison Control , Chinese Center for Disease Control and Prevention , Beijing , 10050 , China . ; ; Tel: +86-10-83132593
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Nicodemus-Johnson J, Naughton KA, Sudi J, Hogarth K, Naurekas ET, Nicolae DL, Sperling AI, Solway J, White SR, Ober C. Genome-Wide Methylation Study Identifies an IL-13-induced Epigenetic Signature in Asthmatic Airways. Am J Respir Crit Care Med 2016; 193:376-85. [PMID: 26474238 PMCID: PMC4803084 DOI: 10.1164/rccm.201506-1243oc] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/15/2015] [Indexed: 01/12/2023] Open
Abstract
RATIONALE Epigenetic changes to airway cells have been proposed as important modulators of the effects of environmental exposures on airway diseases, yet no study to date has shown epigenetic responses to exposures in the airway that correlate with disease state. The type 2 cytokine IL-13 is a key mediator of allergic airway diseases, such as asthma, and is up-regulated in response to many asthma-promoting exposures. OBJECTIVES To directly study the epigenetic response of airway epithelial cells (AECs) to IL-13 and test whether IL-13-induced epigenetic changes differ between individuals with and without asthma. METHODS Genome-wide DNA methylation and gene expression patterns were studied in 58 IL-13-treated and untreated primary AEC cultures and validated in freshly isolated cells of subjects with and without asthma using the Illumina Human Methylation 450K and HumanHT-12 BeadChips. IL-13-mediated comethylation modules were identified and correlated with clinical phenotypes using weighted gene coexpression network analysis. MEASUREMENTS AND MAIN RESULTS IL-13 altered global DNA methylation patterns in cultured AECs and were significantly enriched near genes associated with asthma. Importantly, a significant proportion of this IL-13 epigenetic signature was validated in freshly isolated AECs from subjects with asthma and clustered into two distinct modules, with module 1 correlated with asthma severity and lung function and module 2 with eosinophilia. CONCLUSIONS These results suggest that a single exposure of IL-13 may selectively induce long-lasting DNA methylation changes in asthmatic airways that alter specific AEC pathways and contribute to asthma phenotypes.
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Affiliation(s)
| | | | | | | | | | - Dan L. Nicolae
- Department of Human Genetics
- Section of Genetic Medicine, Department of Medicine, and
- Department of Statistics, University of Chicago, Chicago, Illinois
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Muala A, Rankin G, Sehlstedt M, Unosson J, Bosson JA, Behndig A, Pourazar J, Nyström R, Pettersson E, Bergvall C, Westerholm R, Jalava PI, Happo MS, Uski O, Hirvonen MR, Kelly FJ, Mudway IS, Blomberg A, Boman C, Sandström T. Acute exposure to wood smoke from incomplete combustion--indications of cytotoxicity. Part Fibre Toxicol 2015; 12:33. [PMID: 26511835 PMCID: PMC4625445 DOI: 10.1186/s12989-015-0111-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 10/21/2015] [Indexed: 12/16/2022] Open
Abstract
Background Smoke from combustion of biomass fuels is a major risk factor for respiratory disease, but the underlying mechanisms are poorly understood. The aim of this study was to determine whether exposure to wood smoke from incomplete combustion would elicit airway inflammation in humans. Methods Fourteen healthy subjects underwent controlled exposures on two separate occasions to filtered air and wood smoke from incomplete combustion with PM1 concentration at 314 μg/m3 for 3 h in a chamber. Bronchoscopy with bronchial wash (BW), bronchoalveolar lavage (BAL) and endobronchial mucosal biopsies was performed after 24 h. Differential cell counts and soluble components were analyzed, with biopsies stained for inflammatory markers using immunohistochemistry. In parallel experiments, the toxicity of the particulate matter (PM) generated during the chamber exposures was investigated in vitro using the RAW264.7 macrophage cell line. Results Significant reductions in macrophage, neutrophil and lymphocyte numbers were observed in BW (p < 0.01, <0.05, <0.05, respectively) following the wood smoke exposure, with a reduction in lymphocytes numbers in BAL fluid (<0.01. This unexpected cellular response was accompanied by decreased levels of sICAM-1, MPO and MMP-9 (p < 0.05, <0.05 and <0.01). In contrast, significant increases in submucosal and epithelial CD3+ cells, epithelial CD8+ cells and submucosal mast cells (p < 0.01, <0.05, <0.05 and <0.05, respectively), were observed after wood smoke exposure. The in vitro data demonstrated that wood smoke particles generated under these incomplete combustion conditions induced cell death and DNA damage, with only minor inflammatory responses. Conclusions Short-term exposure to sooty PAH rich wood smoke did not induce an acute neutrophilic inflammation, a classic hallmark of air pollution exposure in humans. While minor proinflammatory lymphocytic and mast cells effects were observed in the bronchial biopsies, significant reductions in BW and BAL cells and soluble components were noted. This unexpected observation, combined with the in vitro data, suggests that wood smoke particles from incomplete combustion could be potentially cytotoxic. Additional research is required to establish the mechanism of this dramatic reduction in airway leukocytes and to clarify how this acute response contributes to the adverse health effects attributed to wood smoke exposure. Trial registration NCT01488500 Electronic supplementary material The online version of this article (doi:10.1186/s12989-015-0111-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ala Muala
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Gregory Rankin
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Maria Sehlstedt
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Jon Unosson
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Jenny A Bosson
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Annelie Behndig
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Jamshid Pourazar
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Robin Nyström
- Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University, Umeå, Sweden
| | - Esbjörn Pettersson
- Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University, Umeå, Sweden
| | - Christoffer Bergvall
- Department of Environmental Science and Analytical Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
| | - Roger Westerholm
- Department of Environmental Science and Analytical Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden
| | - Pasi I Jalava
- Department of Environmental Science, University of Eastern Finland, Kuopio, Finland
| | - Mikko S Happo
- Department of Environmental Science, University of Eastern Finland, Kuopio, Finland
| | - Oskari Uski
- Department of Environmental Science, University of Eastern Finland, Kuopio, Finland
| | | | - Frank J Kelly
- Environmental Research Group, MRC-PHE Centre for Environment and Health, King's College London, London, UK
| | - Ian S Mudway
- Environmental Research Group, MRC-PHE Centre for Environment and Health, King's College London, London, UK
| | - Anders Blomberg
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden
| | - Christoffer Boman
- Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University, Umeå, Sweden
| | - Thomas Sandström
- Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine, Umeå University, Umeå, Sweden.
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Kelly FJ, Fussell JC. Air pollution and public health: emerging hazards and improved understanding of risk. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2015; 37:631-49. [PMID: 26040976 PMCID: PMC4516868 DOI: 10.1007/s10653-015-9720-1] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/28/2015] [Indexed: 05/19/2023]
Abstract
Despite past improvements in air quality, very large parts of the population in urban areas breathe air that does not meet European standards let alone the health-based World Health Organisation Air Quality Guidelines. Over the last 10 years, there has been a substantial increase in findings that particulate matter (PM) air pollution is not only exerting a greater impact on established health endpoints, but is also associated with a broader number of disease outcomes. Data strongly suggest that effects have no threshold within the studied range of ambient concentrations, can occur at levels close to PM2.5 background concentrations and that they follow a mostly linear concentration-response function. Having firmly established this significant public health problem, there has been an enormous effort to identify what it is in ambient PM that affects health and to understand the underlying biological basis of toxicity by identifying mechanistic pathways-information that in turn will inform policy makers how best to legislate for cleaner air. Another intervention in moving towards a healthier environment depends upon the achieving the right public attitude and behaviour by the use of optimal air pollution monitoring, forecasting and reporting that exploits increasingly sophisticated information systems. Improving air quality is a considerable but not an intractable challenge. Translating the correct scientific evidence into bold, realistic and effective policies undisputedly has the potential to reduce air pollution so that it no longer poses a damaging and costly toll on public health.
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Affiliation(s)
- Frank J Kelly
- NIHR Health Protection Research Unit in Health Impact of Environmental Hazards, MRC-PHE Centre for Environment and Health, Facility of Life Sciences and Medicine, King's College London, 150 Stamford Street, London, SE1 9NH, UK,
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Kelly FJ, Fussell JC. Linking ambient particulate matter pollution effects with oxidative biology and immune responses. Ann N Y Acad Sci 2015; 1340:84-94. [DOI: 10.1111/nyas.12720] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 01/12/2015] [Accepted: 01/21/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Frank J. Kelly
- MRC-PHE Centre for Environment and Health; Facility of Life Sciences and Medicine; King's College; London United Kingdom
| | - Julia C. Fussell
- MRC-PHE Centre for Environment and Health; Facility of Life Sciences and Medicine; King's College; London United Kingdom
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Barton DB, Betteridge BC, Earley TD, Curtis CS, Robinson AB, Reynolds PR. Primary alveolar macrophages exposed to diesel particulate matter increase RAGE expression and activate RAGE signaling. Cell Tissue Res 2014; 358:229-38. [PMID: 24859220 DOI: 10.1007/s00441-014-1905-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 04/28/2014] [Indexed: 01/03/2023]
Abstract
Receptors for advanced glycation end-products (RAGE) are members of the immunoglobulin superfamily of cell-surface receptors implicated in mechanisms of pulmonary inflammation. In the current study, we test the hypothesis that RAGE mediates inflammation in primary alveolar macrophages (AMs) exposed to diesel particulate matter (DPM). Quantitative RT-PCR and immunoblotting revealed that RAGE was up-regulated in Raw264.7 cells, an immortalized murine macrophage cell line and primary AMs exposed to DPM for 2 h. Because DPM increased RAGE expression, we exposed Raw264.7 cells and primary AMs isolated from RAGE null and wild-type (WT) mice to DPM prior to the assessment of inflammatory signaling intermediates. DPM led to the activation of Rat sarcoma GTPase (Ras), p38 MAPK and NF-κB in WT AMs and, when compared to WT AMs, these intermediates were diminished in DPM-exposed AMs isolated from RAGE null mice. Furthermore, cytokines implicated in inflammation, including IL-4, IL-12, IL-13 and TNFα, were all significantly decreased in DPM-exposed RAGE null AMs compared to similarly exposed WT AMs. These results demonstrate that diesel-induced inflammatory responses by primary AMs are mediated, at least in part, via RAGE signaling mechanisms. Further work may show that RAGE signaling in both alveolar epithelial cells and resident macrophages is a potential target in the treatment of inflammatory lung diseases exacerbated by environmental pollution.
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Affiliation(s)
- David B Barton
- Department of Physiology and Developmental Biology, Brigham Young University, 3054 Life Sciences Building, Provo, UT, 84602, USA
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Muala A, Sehlstedt M, Bion A, Österlund C, Bosson JA, Behndig AF, Pourazar J, Bucht A, Boman C, Mudway IS, Langrish JP, Couderc S, Blomberg A, Sandström T. Assessment of the capacity of vehicle cabin air inlet filters to reduce diesel exhaust-induced symptoms in human volunteers. Environ Health 2014; 13:16. [PMID: 24621126 PMCID: PMC4007775 DOI: 10.1186/1476-069x-13-16] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/05/2014] [Indexed: 05/05/2023]
Abstract
BACKGROUND Exposure to particulate matter (PM) air pollution especially derived from traffic is associated with increases in cardiorespiratory morbidity and mortality. In this study, we evaluated the ability of novel vehicle cabin air inlet filters to reduce diesel exhaust (DE)-induced symptoms and markers of inflammation in human subjects. METHODS Thirty healthy subjects participated in a randomized double-blind controlled crossover study where they were exposed to filtered air, unfiltered DE and DE filtered through two selected particle filters, one with and one without active charcoal. Exposures lasted for one hour. Symptoms were assessed before and during exposures and lung function was measured before and after each exposure, with inflammation assessed in peripheral blood five hours after exposures. In parallel, PM were collected from unfiltered and filtered DE and assessed for their capacity to drive damaging oxidation reactions in a cell-free model, or promote inflammation in A549 cells. RESULTS The standard particle filter employed in this study reduced PM10 mass concentrations within the exposure chamber by 46%, further reduced to 74% by the inclusion of an active charcoal component. In addition use of the active charcoal filter was associated by a 75% and 50% reduction in NO2 and hydrocarbon concentrations, respectively. As expected, subjects reported more subjective symptoms after exposure to unfiltered DE compared to filtered air, which was significantly reduced by the filter with an active charcoal component. There were no significant changes in lung function after exposures. Similarly diesel exhaust did not elicit significant increases in any of the inflammatory markers examined in the peripheral blood samples 5 hour post-exposure. Whilst the filters reduced chamber particle concentrations, the oxidative activity of the particles themselves, did not change following filtration with either filter. In contrast, diesel exhaust PM passed through the active charcoal combination filter appeared less inflammatory to A549 cells. CONCLUSIONS A cabin air inlet particle filter including an active charcoal component was highly effective in reducing both DE particulate and gaseous components, with reduced exhaust-induced symptoms in healthy volunteers. These data demonstrate the effectiveness of cabin filters to protect subjects travelling in vehicles from diesel exhaust emissions.
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Affiliation(s)
- Ala Muala
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Maria Sehlstedt
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Anne Bion
- Renault Technocentre, Guyancourt, France
| | - Camilla Österlund
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
- Swedish Defence Research Agency, FOI, Umeå, Sweden
| | - Jenny A Bosson
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Annelie F Behndig
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Jamshid Pourazar
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Anders Bucht
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
- Swedish Defence Research Agency, FOI, Umeå, Sweden
| | - Christoffer Boman
- Department of Applied Physics and Electronics, Thermochemical Energy Conversion Laboratory, Umeå University, Umeå, Sweden
| | - Ian S Mudway
- MRC-PHE Centre for Environment and Health, School of Biomedical Sciences, King’s College London, London, UK
| | - Jeremy P Langrish
- BHF/University Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | | | - Anders Blomberg
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
| | - Thomas Sandström
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
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Effects of diesel exposure on lung function and inflammation biomarkers from airway and peripheral blood of healthy volunteers in a chamber study. Part Fibre Toxicol 2013; 10:60. [PMID: 24321138 PMCID: PMC4029460 DOI: 10.1186/1743-8977-10-60] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 07/24/2013] [Indexed: 11/18/2022] Open
Abstract
Background Exposure to diesel exhaust causes inflammatory responses. Previous controlled exposure studies at a concentration of 300 μg/m3 of diesel exhaust particles mainly lasted for 1 h. We prolonged the exposure period and investigated how quickly diesel exhaust can induce respiratory and systemic effects. Methods Eighteen healthy volunteers were exposed twice to diluted diesel exhaust (PM1 ~300 μg/m3) and twice to filtered air (PM1 ~2 μg/m3) for 3 h, seated, in a chamber with a double-blind set-up. Immediately before and after exposure, we performed a medical examination, spirometry, rhinometry, nasal lavage and blood sampling. Nasal lavage and blood samples were collected again 20 h post-exposure. Symptom scores and peak expiratory flow (PEF) were assessed before exposure, and at 15, 75, and 135 min of exposure. Results Self-rated throat irritation was higher during diesel exhaust than filtered air exposure. Clinical signs of irritation in the upper airways were also significantly more common after diesel exhaust exposure (odds ratio=3.2, p<0.01). PEF increased during filtered air, but decreased during diesel exhaust exposure, with a statistically significant difference at 75 min (+4 L/min vs. -10 L/min, p=0.005). Monocyte and total leukocyte counts in peripheral blood were higher after exposure to diesel exhaust than filtered air 20 h post-exposure, and a trend (p=0.07) towards increased serum IL-6 concentrations was also observed 20 h post-exposure. Conclusions Diesel exhaust induced acute adverse effects such as symptoms and signs of irritation, decreased PEF, inflammatory markers in healthy volunteers. The effects were first seen at 75 min of exposure.
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Effects of diesel exhaust particles on primary cultured healthy human conjunctival epithelium. Ann Allergy Asthma Immunol 2012; 110:39-43. [PMID: 23244657 DOI: 10.1016/j.anai.2012.10.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 10/11/2012] [Accepted: 10/23/2012] [Indexed: 11/20/2022]
Abstract
BACKGROUND Air pollution from road traffic is a serious public health problem. Epidemiologic studies have demonstrated adverse health effects associated with environmental pollution. Diesel exhaust is a major contributor to ambient particulate matter air pollution. We studied the effects of exposure to diesel exhaust particles on allergic conjunctivitis using cultured conjunctival epithelial cells obtained from healthy people. OBJECTIVE To identify the factors involved in the human conjunctival epithelial response to diesel exhaust in vitro. METHODS Healthy individuals underwent conjunctival biopsy, and the samples were incubated on conjunctival epithelial sheets. We investigated the effects of exposure to diesel exhaust using GeneChip arrays. The adhesion molecules and cytokines showing increased expression on GeneChip arrays were verified by real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS The GeneChip array showed increased expression of adhesion molecules, cytokines, chemokines, and growth factors after exposure to diesel exhaust. Real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay confirmed that the expression of intercellular adhesion molecule 1 and interleukin 6, in particular, were significantly upregulated. CONCLUSION Our experimental data confirm that exposure to diesel exhaust particles increases inflammatory factor expression in human conjunctiva and thereby contributes to allergic conjunctival responses.
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Zhao C, Liao J, Chu W, Wang S, Yang T, Tao Y, Wang G. Involvement of TLR2 and TLR4 and Th1/Th2 shift in inflammatory responses induced by fine ambient particulate matter in mice. Inhal Toxicol 2012; 24:918-27. [PMID: 23121301 DOI: 10.3109/08958378.2012.731093] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Can Zhao
- Department of Respiratory Medicine, Peking University First Hospital,
Beijing, China
| | - Jiping Liao
- Department of Respiratory Medicine, Peking University First Hospital,
Beijing, China
| | - Weili Chu
- Department of Respiratory Medicine, Peking University First Hospital,
Beijing, China
| | - Suxia Wang
- Department of Electron Microscopy, Peking University First Hospital,
Beijing, China
| | - Tongsheng Yang
- Department of the Animal Centre, Peking University First Hospital,
Beijing, China
| | - Yinghong Tao
- Department of the Animal Centre, Peking University First Hospital,
Beijing, China
| | - Guangfa Wang
- Department of Respiratory Medicine, Peking University First Hospital,
Beijing, China
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Abstract
PURPOSE OF REVIEW Epidemiologic investigation has associated traffic-related air pollution with adverse human health outcomes. The capacity of diesel exhaust particles (DEPs), a major emission source air pollution particle, to initiate an airway inflammation has subsequently been investigated. We review the recent controlled human exposures to diesel exhaust and DEPs, and summarize the investigations into the associations between this emission source air pollution particle and airway inflammation. RECENT FINDINGS Using bronchoalveolar lavage, bronchial biopsies, and sputum collection, studies have demonstrated inflammation in the airways of healthy individuals after exposure to diesel exhaust and DEPs. This inflammation has included neutrophils, eosinophils, mast cells, and lymphocytes. Elevated expression and concentrations of inflammatory mediators have similarly been observed in the respiratory tract after diesel exhaust and DEP exposure. An increased sensitivity of asthmatic individuals to the proinflammatory effects of DEPs has not been confirmed. SUMMARY Inflammation after diesel exhaust and DEP exposure is evident at higher concentrations only; there appears to be a threshold dose for DEPs approximating 300 μg/m. The lack of a biological response to DEPs at lower concentrations may reflect a contribution of gaseous constituents or interactions between DEPs and gaseous air pollutants to the human inflammatory response and function loss.
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Hackett TL, Singhera GK, Shaheen F, Hayden P, Jackson GR, Hegele RG, Van Eeden S, Bai TR, Dorscheid DR, Knight DA. Intrinsic Phenotypic Differences of Asthmatic Epithelium and Its Inflammatory Responses to Respiratory Syncytial Virus and Air Pollution. Am J Respir Cell Mol Biol 2011; 45:1090-100. [DOI: 10.1165/rcmb.2011-0031oc] [Citation(s) in RCA: 158] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Miyata R, van Eeden SF. The innate and adaptive immune response induced by alveolar macrophages exposed to ambient particulate matter. Toxicol Appl Pharmacol 2011; 257:209-26. [PMID: 21951342 DOI: 10.1016/j.taap.2011.09.007] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 08/09/2011] [Accepted: 09/08/2011] [Indexed: 12/16/2022]
Abstract
Emerging epidemiological evidence suggests that exposure to particulate matter (PM) air pollution increases the risk of cardiovascular events but the exact mechanism by which PM has adverse effects is still unclear. Alveolar macrophages (AM) play a major role in clearing and processing inhaled PM. This comprehensive review of research findings on immunological interactions between AM and PM provides potential pathophysiological pathways that interconnect PM exposure with adverse cardiovascular effects. Coarse particles (10 μm or less, PM(10)) induce innate immune responses via endotoxin-toll-like receptor (TLR) 4 pathway while fine (2.5 μm or less, PM(2.5)) and ultrafine particles (0.1 μm or less, UFP) induce via reactive oxygen species generation by transition metals and/or polyaromatic hydrocarbons. The innate immune responses are characterized by activation of transcription factors [nuclear factor (NF)-κB and activator protein-1] and the downstream proinflammatory cytokine [interleukin (IL)-1β, IL-6, and tumor necrosis factor-α] production. In addition to the conventional opsonin-dependent phagocytosis by AM, PM can also be endocytosed by an opsonin-independent pathway via scavenger receptors. Activation of scavenger receptors negatively regulates the TLR4-NF-κB pathway. Internalized particles are subsequently subjected to adaptive immunity involving major histocompatibility complex class II (MHC II) expression, recruitment of costimulatory molecules, and the modulation of the T helper (Th) responses. AM show atypical antigen presenting cell maturation in which phagocytic activity decreases while both MHC II and costimulatory molecules remain unaltered. PM drives AM towards a Th1 profile but secondary responses in a Th1- or Th-2 up-regulated milieu drive the response in favor of a Th2 profile.
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Affiliation(s)
- Ryohei Miyata
- The James Hogg iCAPTURE Centre, University of British Columbia, St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, Canada
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Farina F, Sancini G, Mantecca P, Gallinotti D, Camatini M, Palestini P. The acute toxic effects of particulate matter in mouse lung are related to size and season of collection. Toxicol Lett 2011; 202:209-17. [DOI: 10.1016/j.toxlet.2011.01.031] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 01/27/2011] [Accepted: 01/31/2011] [Indexed: 11/26/2022]
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Yoshizaki K, Brito JM, Toledo AC, Nakagawa NK, Piccin VS, Junqueira MS, Negri EM, Carvalho ALN, Oliveira APLD, Lima WTD, Saldiva PHN, Mauad T, Macchione M. Subchronic effects of nasally instilled diesel exhaust particulates on the nasal and airway epithelia in mice. Inhal Toxicol 2011; 22:610-7. [PMID: 20429853 DOI: 10.3109/08958371003621633] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Diesel exhaust is the major source of ultrafine particles released during traffic-related pollution. Subjects with chronic respiratory diseases are at greater risk for exacerbations during exposure to air pollution. This study evaluated the effects of subchronic exposure to a low-dose of diesel exhaust particles (DEP). Sixty male BALB/c mice were divided into two groups: (a) Saline: nasal instillation of saline (n = 30); and (b) DEP: nasal instillation of 30 microg of DEP/10 microl of saline (n = 30). Nasal instillations were performed 5 days a week, over 30 and 60 days. Animals were anesthetized with pentobarbital sodium (50 mg/kg intraperitoneal [i.p.]) and sacrificed by exsanguination. Bronchoalveolar lavage (BAL) fluid was performed to evaluate the inflammatory cell count and the concentrations of the interleukin (IL)-4, IL-10, and IL-13 by enzyme-linked immunosorbent assay (ELISA). The gene expression of oligomeric mucus/gel-forming (Muc5ac) was evaluated by real-time polymerase chain reaction (PCR). Histological analysis in the nasal septum and bronchioles was used to evaluate the bronchial and nasal epithelium thickness as well as the acidic and neutral nasal mucus content. The saline group (30 and 60 days) did not show any changes in any of the parameters. However, the instillation of DEP over 60 days increased the expression of Muc5ac in the lungs and the acid mucus content in the nose compared with the 30-day treatment, and it increased the total leukocytes in the BAL and the nasal epithelium thickness compared with saline for 60 days. Cytokines concentrations in the BAL were detectable, with no differences among the groups. Our data suggest that a low-dose of DEP over 60 days induces respiratory tract inflammation.
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Affiliation(s)
- K Yoshizaki
- Laboratory of Experimental Atmospheric Pollution (LPAE), University of São Paulo, Avenida Dr. Arnaldo 455, São Paulo, Brazil
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Hesterberg TW, Long CM, Lapin CA, Hamade AK, Valberg PA. Diesel exhaust particulate (DEP) and nanoparticle exposures: what do DEP human clinical studies tell us about potential human health hazards of nanoparticles? Inhal Toxicol 2010; 22:679-94. [PMID: 20462394 DOI: 10.3109/08958371003758823] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Engineered nanoparticles (ENPs) are increasingly tested in cellular and laboratory-animal experiments for hazard potential, but there is a lack of health effects data for humans exposed to ENPs. However, human data for another source of nanoparticle (NP) exposure are available, notably for the NPs contained in diesel exhaust particulate (DEP). Studies of human volunteers exposed to diesel exhaust (DE) in research settings report DEP-NP number concentrations (i.e., >10(6) particles/cm(3)) that exceed number concentrations reported for worst-case exposure conditions for workers manufacturing and handling ENPs. Recent human DE exposure studies, using sensitive physiological instrumentation and well-characterized exposure concentrations and durations, suggest that elevated DE exposures from pre-2007 engines may trigger short-term changes in, for example, lung and systemic inflammation, thrombogenesis, vascular function, and brain activity. Considerable uncertainty remains both as to which DE constituents underlie the observed responses (i.e., DEP NPs, DEP mass, DE gases), and as to the implications of the observed short-term changes for the development of disease. Even so, these DE human clinical data do not give evidence of a unique toxicity for NPs as compared to other small particles. Of course, physicochemical properties of toxicological relevance may differ between DEP NPs and other NPs, yet overall, the DE human clinical data do not support the idea that elevated levels of NPs per se (at least in the DEP context) must be acutely toxic by virtue of their nano-sized nature alone.
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Sehlstedt M, Dove R, Boman C, Pagels J, Swietlicki E, Löndahl J, Westerholm R, Bosson J, Barath S, Behndig AF, Pourazar J, Sandström T, Mudway IS, Blomberg A. Antioxidant airway responses following experimental exposure to wood smoke in man. Part Fibre Toxicol 2010; 7:21. [PMID: 20727160 PMCID: PMC2936868 DOI: 10.1186/1743-8977-7-21] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Accepted: 08/20/2010] [Indexed: 11/21/2022] Open
Abstract
Background Biomass combustion contributes to the production of ambient particulate matter (PM) in rural environments as well as urban settings, but relatively little is known about the health effects of these emissions. The aim of this study was therefore to characterize airway responses in humans exposed to wood smoke PM under controlled conditions. Nineteen healthy volunteers were exposed to both wood smoke, at a particulate matter (PM2.5) concentration of 224 ± 22 μg/m3, and filtered air for three hours with intermittent exercise. The wood smoke was generated employing an experimental set-up with an adjustable wood pellet boiler system under incomplete combustion. Symptoms, lung function, and exhaled NO were measured over exposures, with bronchoscopy performed 24 h post-exposure for characterisation of airway inflammatory and antioxidant responses in airway lavages. Results Glutathione (GSH) concentrations were enhanced in bronchoalveolar lavage (BAL) after wood smoke exposure vs. air (p = 0.025), together with an increase in upper airway symptoms. Neither lung function, exhaled NO nor systemic nor airway inflammatory parameters in BAL and bronchial mucosal biopsies were significantly affected. Conclusions Exposure of healthy subjects to wood smoke, derived from an experimental wood pellet boiler operating under incomplete combustion conditions with PM emissions dominated by organic matter, caused an increase in mucosal symptoms and GSH in the alveolar respiratory tract lining fluids but no acute airway inflammatory responses. We contend that this response reflects a mobilisation of GSH to the air-lung interface, consistent with a protective adaptation to the investigated wood smoke exposure.
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Affiliation(s)
- Maria Sehlstedt
- Department of Public Health and Clinical Medicine, Division of Medicine, Umeå University, Umeå, Sweden
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Semlali A, Jacques E, Koussih L, Gounni AS, Chakir J. Thymic stromal lymphopoietin-induced human asthmatic airway epithelial cell proliferation through an IL-13-dependent pathway. J Allergy Clin Immunol 2010; 125:844-50. [PMID: 20236697 DOI: 10.1016/j.jaci.2010.01.044] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 01/22/2010] [Accepted: 01/25/2010] [Indexed: 12/11/2022]
Abstract
BACKGROUND Thymic stromal lymphopoietin (TSLP) plays a pivotal role in the initiation of allergic airway inflammation. This cytokine is produced by several cell types, including human epithelial cells. OBJECTIVE We sought to determine the effect of TSLP on proliferation and repair of epithelial cells isolated from asthmatic patients and healthy subjects. METHODS Expression of TSLP receptor (TSLPR) and its response to inhaled corticosteroids was evaluated on bronchial biopsy specimens of healthy control subjects and asthmatic patients by means of immunohistochemistry. TSLPR, TSLP, and IL-13 mRNA expression was determined by means of quantitative PCR, and protein expression was measured by means of ELISA and Western blotting in epithelial cells isolated from asthmatic subjects compared with those isolated from healthy control subjects. The effect of TSLP on cell proliferation and wound healing was performed. RESULTS TSLPR is expressed by bronchial epithelial cells in bronchial biopsy specimens and in cultured cells, with no difference between asthmatic patients and healthy control subjects. Inhaled corticosteroids did not affect this expression. TSLP mRNA and protein levels were significantly higher in epithelial cells isolated from asthmatic patients compared with those from healthy control subjects. TSLP stimulated IL-13 production by bronchial epithelial cells. TSLP induced airway epithelial cell proliferation and enhanced epithelial injury repair. This effect was abrogated with IL-13 neutralization. CONCLUSIONS Our data indicate that epithelial cells express TSLPR and that TSLP induces bronchial epithelial cell proliferation and increases injury repair through IL-13 production. This suggests that TSLP and IL-13 loops play a homeostatic role on epithelial cell proliferation and repair.
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Affiliation(s)
- Abdelhabib Semlali
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie du Québec, Université Laval, Quebec City, Quebec
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Non-cancer health effects of diesel exhaust: A critical assessment of recent human and animal toxicological literature. Crit Rev Toxicol 2009; 39:195-227. [DOI: 10.1080/10408440802220603] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Sehlstedt M, Andersen GN, Nilsson K, Blomberg A, Mincheva-Nilsson L, Waldenström A, Rantapää-Dahlqvist S, Sandström T. Suppressed signal transduction in the bronchial epithelium of patients with systemic sclerosis. Respir Med 2008; 103:301-8. [PMID: 18819788 DOI: 10.1016/j.rmed.2008.08.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 07/16/2008] [Accepted: 08/11/2008] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Systemic sclerosis (SSc) is an autoimmune disorder, which frequently affects the lungs, with manifestations of interstitial lung disease (ILD) with lung fibrosis and of pulmonary hypertension. The pathogenesis remains largely unrecognised. OBJECTIVE The aim of this study was to elucidate the inflammation in the bronchial mucosa in patients with SSc. SUBJECTS AND METHODS Twenty-three subjects diagnosed with SSc participated. Twelve of the SSc patients showed signs of ILD, four were smokers and seven were treated with oral corticosteroids. Seventeen non-smoking, age- and sex-matched healthy subjects served as controls. Bronchoscopy was performed to sample endobronchial mucosal biopsies, which were immunohistochemically stained using a panel of antibodies against inflammatory markers. RESULTS The number of neutrophils was significantly elevated in the submucosa of SSc patients, regardless of ILD, or whether the subject was smoking or using oral corticosteroids. No up-regulation of neutrophil chemoattractants or cytokines was seen in the bronchial epithelium. The signal transduction pathways and adhesion molecule expression tended to be suppressed or unchanged in SSc patients compared with controls. CONCLUSION It is concluded that SSc is associated with a chronic neutrophilic inflammation in the bronchial mucosal, with signs of suppressed signal transduction, regardless of the presence of interstitial lung disease.
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Affiliation(s)
- Maria Sehlstedt
- Department of Respiratory Medicine and Allergy, University Hospital, 901 85 Umeå, Sweden.
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Chen E, Schreier HMC, Strunk RC, Brauer M. Chronic traffic-related air pollution and stress interact to predict biologic and clinical outcomes in asthma. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:970-5. [PMID: 18629323 PMCID: PMC2453169 DOI: 10.1289/ehp.11076] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2007] [Accepted: 02/26/2008] [Indexed: 05/04/2023]
Abstract
BACKGROUND Previous research has documented effects of both physical and social environmental exposures on childhood asthma. However, few studies have considered how these two environments might interact to affect asthma. OBJECTIVE This study aimed to test interactions between chronic exposure to traffic-related air pollution and chronic family stress in predicting biologic and clinical outcomes in children with asthma. METHOD Children with asthma (n = 73, 9-18 years of age) were interviewed about life stress, and asthma-relevant inflammatory markers [cytokine production, immunoglobulin E (IgE), eosinophil counts] were measured. Parents reported on children's symptoms. Children completed daily diaries of symptoms and peak expiratory flow rate (PEFR) measures at baseline and 6 months later. Exposure to traffic-related air pollution was assessed using a land use regression model for nitrogen dioxide concentrations. RESULTS NO(2) by stress interactions were found for interleukin-5 (beta for interaction term = -0.31, p = 0.02), IgE (interaction beta = -0.29, p = 0.02), and eosinophil counts (interaction beta = -0.24, p = 0.04). These interactions showed that higher chronic stress was associated with heightened inflammatory profiles as pollution levels decreased. Longitudinally, NO(2) by stress interactions emerged for daily diary symptoms (interaction beta = -0.28, p = 0.02), parent-reported symptoms (interaction beta = -0.25, p = 0.07), and PEFR (interaction beta = 0.30, p = 0.03). These interactions indicated that higher chronic stress was associated with increases over time in symptoms and decreases over time in PEFR as pollution levels decreased. CONCLUSIONS The physical and social environments interacted in predicting both biologic and clinical outcomes in children with asthma, suggesting that when pollution exposure is more modest, vulnerability to asthma exacerbations may be heightened in children with higher chronic stress.
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Affiliation(s)
- Edith Chen
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
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Pourazar J, Blomberg A, Kelly FJ, Davies DE, Wilson SJ, Holgate ST, Sandström T. Diesel exhaust increases EGFR and phosphorylated C-terminal Tyr 1173 in the bronchial epithelium. Part Fibre Toxicol 2008; 5:8. [PMID: 18460189 PMCID: PMC2405801 DOI: 10.1186/1743-8977-5-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Accepted: 05/06/2008] [Indexed: 01/13/2023] Open
Abstract
Background Epidemiological studies have demonstrated adverse health effects of environmental pollution. Diesel exhaust (DE) is a major contributor to particulate matter pollution. DE exposure has been shown to induce a pronounced inflammatory response in the airways, together with an enhanced epithelial expression of cytokines such as IL-8, Gro-α, IL-13 and activation of redox sensitive transcription factors (NFκB, AP-1), and MAP kinases (p38, JNK). The aim of the present investigation was to elucidate the involvement of the epidermal growth factor receptor (EGFR) signalling pathway in the epithelial response to DE in-vivo. Results Immunohistochemical staining was used to quantify the expression of the EGFR, phosphorylated Tyrosine residues, MEK and ERK in the bronchial epithelium of archived biopsies from 15 healthy subjects following exposure to DE (PM10, 300 μg/m3) and air. DE induced a significant increases in the expression of EGFR (p = 0.004) and phosphorylated C-terminal Tyr 1173 (p = 0.02). Other investigated EGFR tyrosine residues, Src related tyrosine (Tyr 416), MEK and ERK pathway were not changed significantly by DE. Conclusion Exposure to DE (PM10, 300 μg/m3) caused enhanced EGFR expression and phosphorylation of the tyrosine residue (Tyr 1173) which is in accordance with the previously demonstrated activation of the JNK, AP-1, p38 MAPK and NFkB pathways and associated downstream signalling and cytokine production. No effects were seen on the MEK and ERK pathway suggesting that at the investigated time point (6 hours post exposure) there was no proliferative/differentiation signalling in the bronchial epithelium. The present findings suggest a key role for EGFR in the bronchial response to diesel exhaust.
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Affiliation(s)
- Jamshid Pourazar
- Department of Respiratory Medicine and Allergy, University Hospital, Umeå, Sweden.
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Abstract
"Would you tell me please, which way I ought to go from here," asked Alice. "That depends a good deal on where you want to go to," said the cat. (Lewis Carroll, Alice's Adventures in Wonderland) A large number of epidemiological studies show positive correlations between increasing levels of particulate matter (PM) in urban air and short-term morbidity and mortality for diverse acute cardiopulmonary diseases. Brought about by PM increments, inflammation is thought to exacerbate preexisting inflammatory diseases. Experimental evidence suggests a hierarchical oxidative stress model, in which a weakened antioxidant defense, as observed in disease or induced by inhaled particles, increases the PM ability to cause lung inflammation, accounting for exacerbations that occur in asthmatics and in patients with chronic obstructive lung disease. The role of PM-induced inflammation leading to acute cardiovascular events such as arrhythmia, heart failure, and myocardial infarction is more speculative. There is neither clear-cut evidence in humans that inhaled PM could get as far as blood circulation nor that proinflammatory mediators are significantly released from inflamed lung tissues, nor that blood coagulability is critically altered. As a whole, data in humans indicate that short-term inflammatory responses to PM are not always detected; they are usually mild and loosely correlated with functional changes. Among these studies, the diversity of PM characteristics, dose metrics, and endpoints hampers a clear discerning of inflammatory mechanism(s). Thus, the question arises as to whether inflammation represents the mechanism of acute cardiopulmonary PM toxicities in susceptible individuals, or rather an event that may coexist with other relevant mechanism(s). This review article discusses the evidence in humans linking short-term PM increments to inflammation and to exacerbations of cardiopulmonary diseases. Although there is a large amount of data available, there still remains a gulf between the number of epidemiological and panel studies and that of controlled exposures. Research on controlled exposure needs expanding, so that the results of time-series and panel studies will be better understood and short-term standards for human exposure may be more confidently allocated.
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Affiliation(s)
- Maria Luisa Scapellato
- Dipartimento di Medicina Ambientale e Sanità Pubblica, Università degli Studi di Padova, Padova, Italy.
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Allahverdian S, Harada N, Singhera GK, Knight DA, Dorscheid DR. Secretion of IL-13 by airway epithelial cells enhances epithelial repair via HB-EGF. Am J Respir Cell Mol Biol 2007; 38:153-60. [PMID: 17717322 PMCID: PMC2214672 DOI: 10.1165/rcmb.2007-0173oc] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Inappropriate repair after injury to the epithelium generates persistent activation, which may contribute to airway remodeling. In the present study we hypothesized that IL-13 is a normal mediator of airway epithelial repair. Mechanical injury of confluent airway epithelial cell (AEC) monolayers induced expression and release of IL-13 in a time-dependent manner coordinate with repair. Neutralizing of IL-13 secreted from injured epithelial cells by shIL-13Ralpha2.FC significantly reduced epithelial repair. Moreover, exogenous IL-13 enhanced epithelial repair and induced epidermal growth factor receptor (EGFR) phosphorylation. We examined secretion of two EGFR ligands, epidermal growth factor (EGF) and heparin-binding EGF (HB-EGF), after mechanical injury. Our data showed a sequential release of the EGF and HB-EGF by AEC after injury. Interestingly, we found that IL-13 induces HB-EGF, but not EGF, synthesis and release from AEC. IL-13-induced EGFR phosphorylation and the IL-13-reparative effect on AEC are mediated via HB-EGF. Finally, we demonstrated that inhibition of EGFR tyrosine kinase activity by tyrphostin AG1478 increases IL-13 release after injury, suggesting negative feedback between EGFR and IL-13 during repair. Our data, for the first time, showed that IL-13 plays an important role in epithelial repair, and that its effect is mediated through the autocrine release of HB-EGF and activation of EGFR. Dysregulation of EGFR phosphorylation may contribute to a persistent repair phenotype and chronically increased IL-13 release, and in turn result in airway remodeling.
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Affiliation(s)
- Sima Allahverdian
- James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, St. Paul's Hospital, Room 166, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6 Canada
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Li R, Meng Z. Effects of SO2 derivatives on expressions of MUC5AC and IL-13 in human bronchial epithelial cells. Arch Toxicol 2007; 81:867-74. [PMID: 17520240 DOI: 10.1007/s00204-007-0212-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Accepted: 04/19/2007] [Indexed: 10/23/2022]
Abstract
Sulfur dioxide (SO2) is a common air pollutant, and inhaled SO2 in airway epithelium easily forms its soluble derivatives in vivo (bisulfite and sulfite), which are toxic to the respiratory system and related to the exacerbation of asthma. To investigate the effects of SO2 derivatives on the expressions of asthma related genes (MUC5AC and IL-13), the mRNA and protein levels of the two genes in cultured human bronchial epithelial (BEP2D) cells were analyzed using real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assay, immunocytochemistry method and enzyme-linked immunosorbent assay (ELISA), respectively. The results showed that the mRNA expressions of MUC5AC and IL-13 were significantly increased at different concentrations of SO2 derivatives (0.0001, 0.001, 0.01, 0.1 and 1.0 mM), and the maximum appeared at 0.01 mM for MUC5AC (3.9-fold) or at 0.001 mM for IL-13 (4.7-fold). Meanwhile, SO2 derivatives significantly increased the mRNA levels at 0, 0.5, 1, 4 and 24 h post-exposure with the maximum at 4 h post-exposure (25-fold for MUC5AC and 41-fold for IL-13). Furthermore, the protein levels of MUC5AC and IL-13 in BEP2D cells were significantly increased at different concentrations and different time courses exposed to SO2 derivatives, along with the maximum at 4 h post-exposure. These results lead to a conclusion that SO2 derivatives can increase the expressions of MUC5AC and IL-13 genes on the transcription and translation levels, and it suggests that SO2 derivatives can induce mucus over-production and inflammation responses in human bronchial epithelial cells and may have relations with asthma diseases. This might be one of the possible mechanisms that SO2 aggravates asthma disease.
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Affiliation(s)
- Ruijin Li
- Institute of Environmental Medicine and Toxicology, Shanxi University, Taiyuan 030006, China
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Törnqvist H, Mills NL, Gonzalez M, Miller MR, Robinson SD, Megson IL, Macnee W, Donaldson K, Söderberg S, Newby DE, Sandström T, Blomberg A. Persistent endothelial dysfunction in humans after diesel exhaust inhalation. Am J Respir Crit Care Med 2007; 176:395-400. [PMID: 17446340 DOI: 10.1164/rccm.200606-872oc] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Exposure to combustion-derived air pollution is associated with an early (1-2 h) and sustained (24 h) rise in cardiovascular morbidity and mortality. We have previously demonstrated that inhalation of diesel exhaust causes an immediate (within 2 h) impairment of vascular and endothelial function in humans. OBJECTIVES To investigate the vascular and systemic effects of diesel exhaust in humans 24 hours after inhalation. METHODS Fifteen healthy men were exposed to diesel exhaust (particulate concentration, 300 microg/m(3)) or filtered air for 1 hour in a double-blind, randomized, crossover study. Twenty-four hours after exposure, bilateral forearm blood flow, and inflammatory and fibrinolytic markers were measured before and during unilateral intrabrachial bradykinin (100-1,000 pmol/min), acetylcholine (5-20 microg/min), sodium nitroprusside (2-8 microg/min), and verapamil (10-100 microg/min) infusions. MEASUREMENTS AND MAIN RESULTS Resting forearm blood flow, blood pressure, and basal fibrinolytic markers were similar 24 hours after either exposure. Diesel exhaust increased plasma cytokine concentrations (tumor necrosis factor-alpha and interleukin-6, p < 0.05 for both) but appeared to reduce acetylcholine (p = 0.01), and bradykinin (p = 0.08) induced forearm vasodilatation. In contrast, there were no differences in either endothelium-independent (sodium nitroprusside and verapamil) vasodilatation or bradykinin-induced acute plasma tissue plasminogen activator release. CONCLUSIONS Twenty-four hours after diesel exposure, there is a selective and persistent impairment of endothelium-dependent vasodilatation that occurs in the presence of mild systemic inflammation. These findings suggest that combustion-derived air pollution may have important systemic and adverse vascular effects for at least 24 hours after exposure.
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Affiliation(s)
- Håkan Törnqvist
- Department of Respiratory Medicine and Allergy, Umeå University Hospital, SE-901 85 Umeå, Sweden
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Bosson J, Pourazar J, Forsberg B, Adelroth E, Sandström T, Blomberg A. Ozone enhances the airway inflammation initiated by diesel exhaust. Respir Med 2006; 101:1140-6. [PMID: 17196810 DOI: 10.1016/j.rmed.2006.11.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 10/26/2006] [Accepted: 11/16/2006] [Indexed: 11/16/2022]
Abstract
Exposure to air pollution is associated with adverse health effects, with particulate matter (PM) and ozone (O(3)) both indicated to be of considerable importance. Diesel engine exhaust (DE) and O(3) generate substantial inflammatory effects in the airways. However, as yet it has not been determined whether a subsequent O(3) exposure would add to the diesel-induced airway inflammatory effects. Healthy subjects underwent two separate exposure series: A 1-h DE exposure at a PM-concentration of 300 microg/m(3), followed after 5h by a 2-h exposure to filtered air and 0.2 ppm O(3), respectively. Induced sputum was collected 18 h after the second exposure. A significant increase in the percentage of neutrophils (PMN) and concentration of myeloperoxidase (MPO) was seen in sputum post DE+O(3) vs. DE+air (p<0.05 and <0.05, respectively). Significant associations were observed between the responses in MPO concentration and total PMN cells (p=0.001), and also between MPO and matrix metalloproteinase-9 (MMP-9) (p<0.001). The significant increase of PMN and MPO after the DE+O(3) exposures, compared to DE+air, denotes an O(3)-induced magnification of the DE-induced inflammation. Furthermore, the correlation between responses in MPO and number of PMNs and MMP-9 illustrate that the PMNs are activated, resulting in a more potent inflammatory response. The present study indicates that O(3) exposure adds significantly to the inflammatory response that is established by diesel exhaust. This interaction between exposure to particulate pollution and O(3) in sequence should be taken into consideration when health effects of air pollution are considered.
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Affiliation(s)
- Jenny Bosson
- Department of Respiratory Medicine and Allergy, University Hospital, SE-901 85 Umeå, Sweden.
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Toner SM, Sodeman DA, Prather KA. Single particle characterization of ultrafine and accumulation mode particles from heavy duty diesel vehicles using aerosol time-of-flight mass spectrometry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:3912-21. [PMID: 16830561 DOI: 10.1021/es051455x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The aerodynamic size and chemical composition of individual ultrafine and accumulation mode particle emissions (Da = 50-300 nm) were characterized to determine mass spectral signatures for heavy duty diesel vehicle (HDDV) emissions that can be used for atmospheric source apportionment. As part of this study, six in-use HDDVs were operated on a chassis dynamometer using the heavy heavy-duty diesel truck (HHDDT) five-cycle driving schedule under different simulated weight loads. The exhaust emissions were passed through a dilution/residence system to simulate atmospheric dilution conditions, after which an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS) was used to sample and characterize the HDDV exhaust particles in real-time. This represents the first study where refractory species including elemental carbon and metals are characterized directly in HDDV emissions using on-line mass spectrometry. The top three particle classes observed with the UF-ATOFMS comprise 91% of the total particles sampled and show signatures indicative of a combination of elemental carbon (EC) and engine lubricating oil. In addition to the vehicle make/year, the effects of driving cycle and simulated weight load on exhaust particle size and composition were investigated.
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Affiliation(s)
- Stephen M Toner
- Department of Chemistry and Biochemistry, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093-0314, USA
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Pourazar J, Mudway IS, Samet JM, Helleday R, Blomberg A, Wilson SJ, Frew AJ, Kelly FJ, Sandström T. Diesel exhaust activates redox-sensitive transcription factors and kinases in human airways. Am J Physiol Lung Cell Mol Physiol 2005; 289:L724-30. [PMID: 15749742 DOI: 10.1152/ajplung.00055.2005] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Diesel exhaust (DE) is a major component of airborne particulate matter. In previous studies we have described the acute inflammatory response of the human airway to inhaled DE. This was characterized by neutrophil, mast cell, and lymphocyte infiltration into the bronchial mucosa with enhanced epithelial expression of IL-8, Gro-alpha, and IL-13. In the present study, we investigated whether redox-sensitive transcription factors were activated as a consequence of DE exposure, consistent with oxidative stress triggering airway inflammation. In archived biopsies from 15 healthy subjects exposed to DE [particulates with a mass median diameter of <10 mum, 300 microg/m3] and air, immunohistochemical staining was used to quantify the expression of the transcription factors NF-kappaB (p65) and AP-1 (c-jun and c-fos), as well their upstream MAPKs, p38 and JNK, in the bronchial epithelium. In addition, phosphorylation of tyrosine residues was examined. DE induced a significant increase in the nuclear translocation of NF-kappaB (P = 0.02), AP-1 (P = 0.02), phosphorylated JNK (P = 0.04), and phosphorylated p38 (P = 0.01), as well as an increase in total (cytoplasmic + nuclear) immunostaining of phosphorylated p38 (P = 0.03). A significant increase in nuclear phosphorylated tyrosine was also observed (P < 0.05). These observations demonstrate that DE activates redox-sensitive transcription factors in vivo consistent with oxidative stress triggering the increased synthesis of proinflammatory cytokines.
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Affiliation(s)
- Jamshid Pourazar
- Dept. of Respiratory Medicine and Allergy, Univ. Hospital, SE-901 85 Umeå, Sweden
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