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Bailey MJ, Holzhausen EA, Morgan ZEM, Naik N, Shaffer JP, Liang D, Chang HH, Sarnat J, Sun S, Berger PK, Schmidt KA, Lurmann F, Goran MI, Alderete TL. Postnatal exposure to ambient air pollutants is associated with the composition of the infant gut microbiota at 6-months of age. Gut Microbes 2022; 14:2105096. [PMID: 35968805 PMCID: PMC9466616 DOI: 10.1080/19490976.2022.2105096] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Epidemiological studies in adults have shown that exposure to ambient air pollution (AAP) is associated with the composition of the adult gut microbiome, but these relationships have not been examined in infancy. We aimed to determine if 6-month postnatal AAP exposure was associated with the infant gut microbiota at 6 months of age in a cohort of Latino mother-infant dyads from the Southern California Mother's Milk Study (n = 103). We estimated particulate matter (PM2.5 and PM10) and nitrogen dioxide (NO2) exposure from birth to 6-months based on residential address histories. We characterized the infant gut microbiota using 16S rRNA amplicon sequencing at 6-months of age. At 6-months, the gut microbiota was dominated by the phyla Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. Our results show that, after adjusting for important confounders, postnatal AAP exposure was associated with the composition of the gut microbiota. As an example, PM10 exposure was positively associated with Dialister, Dorea, Acinetobacter, and Campylobacter while PM2.5 was positively associated with Actinomyces. Further, exposure to PM10 and PM2.5 was inversely associated with Alistipes and NO2 exposure was positively associated with Actinomyces, Enterococcus, Clostridium, and Eubacterium. Several of these taxa have previously been linked with systemic inflammation, including the genera Dialister and Dorea. This study provides the first evidence of significant associations between exposure to AAP and the composition of the infant gut microbiota, which may have important implications for future infant health and development.
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Affiliation(s)
- Maximilian J. Bailey
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | | | | | - Noopur Naik
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Justin P. Shaffer
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Donghai Liang
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Howard H. Chang
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jeremy Sarnat
- Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Shan Sun
- Department of Bioinformatics and Genomics, University of North Carolina at Charlotte, Charlotte, NC, USA
| | - Paige K. Berger
- Department of Pediatrics, The Saban Research Institute, Children’s Hospital of Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Kelsey A. Schmidt
- Department of Pediatrics, The Saban Research Institute, Children’s Hospital of Los Angeles, University of Southern California, Los Angeles, CA, USA
| | | | - Michael I. Goran
- Department of Pediatrics, The Saban Research Institute, Children’s Hospital of Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Tanya L. Alderete
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA,CONTACT Tanya L. Alderete Department of Integrative Physiology, University of Colorado, Boulder, CO80309, USA
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Thomas J, Thomson EM. Modulation by Ozone of Glucocorticoid-Regulating Factors in the Lungs in Relation to Stress Axis Reactivity. TOXICS 2021; 9:toxics9110290. [PMID: 34822681 PMCID: PMC8622418 DOI: 10.3390/toxics9110290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 12/17/2022]
Abstract
Exposure to air pollutants increases levels of circulating glucocorticoid stress hormones that exert profound effects relevant to health and disease. However, the nature and magnitude of tissue-level effects are modulated by factors that regulate local glucocorticoid activity; accordingly, inter-individual differences could contribute to susceptibility. In the present study, we characterized effects of ozone (O3) inhalation on glucocorticoid-regulating factors in the lungs of rat strains with contrasting hypothalamic–pituitary–adrenal stress axis responses. Hyper-responsive Fischer (F344) and less responsive Lewis (LEW) rats were exposed to air or 0.8 ppm O3 for 4 h by nose-only inhalation. Levels of the high-specificity and -affinity corticosteroid-binding globulin protein increased in the lungs of both strains proportional to the rise in corticosterone levels following O3 exposure. Ozone reduced the ratio of 11β-hydroxysteroid dehydrogenase type 1 (HSDB1)/HSDB2 mRNA in the lungs of F344 but not LEW, indicating strain-specific transcriptional regulation of the major glucocorticoid metabolism factors that control tissue-level action. Intercellular adhesion molecule (ICAM)-1 and total elastase activity were increased by O3 in both strains, consistent with extravasation and tissue remodeling processes following injury. However, mRNA levels of inflammatory markers were significantly higher in the lungs of O3-exposed LEW compared to F344. The data show that strain differences in the glucocorticoid response to O3 are accompanied by corresponding changes in regulatory factors, and that these effects are collectively associated with a differential inflammatory response to O3. Innate differences in glucocorticoid regulatory factors may modulate the pulmonary effects of inhaled pollutants, thereby contributing to differential susceptibility.
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Affiliation(s)
- Jith Thomas
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON K1A 0K9, Canada;
| | - Errol M. Thomson
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON K1A 0K9, Canada;
- Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
- Correspondence: ; Tel.: +1-613-941-7151
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Thomas J, Stalker A, Breznan D, Thomson EM. Ozone-dependent increases in lung glucocorticoids and macrophage response: Effect modification by innate stress axis function. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2021; 86:103662. [PMID: 33878450 DOI: 10.1016/j.etap.2021.103662] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 04/13/2021] [Accepted: 04/15/2021] [Indexed: 06/12/2023]
Abstract
Although considerable inter-individual variability exists in health effects associated with air pollutant exposure, underlying reasons remain unclear. We examined whether innate differences in stress axis function modify lung glucocorticoid and macrophage responses to ozone (O3). Highly-stress responsive Fischer (F344) and less responsive Lewis (LEW) rats were exposed for 4 h by nose-only inhalation to air or O3 (0.8 ppm). Ozone increased corticosterone recovered by bronchoalveolar lavage in both strains (F344 > LEW). Higher corticosterone in F344 was associated with a blunted response to O3 of macrophage pro-inflammatory genes compared to LEW. Pharmacological inhibition of O3-dependent corticosterone production in F344 enhanced the inflammatory gene response to O3, mimicking the LEW phenotype. Examination of potential impacts of glucocorticoids on macrophage function using a human monocyte-derived macrophage cell line (THP-1) showed that cortisol modified phagocytosis in a macrophage phenotype-dependent manner. Overall, our data implicate endogenous glucocorticoids in the regulation of pulmonary macrophage responses to O3.
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Affiliation(s)
- Jith Thomas
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9, Canada
| | - Andrew Stalker
- Biologic and Radiopharmaceutical Drugs Directorate, Centre for Biologics Evaluation, Health Canada, Ottawa, Ontario, K1A 0K9, Canada
| | - Dalibor Breznan
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9, Canada
| | - Errol M Thomson
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, K1A 0K9, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, K1H 8M5, Canada.
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Thomson EM, Filiatreault A, Williams A, Rider CF, Carlsten C. Exposure to Diesel Exhaust and Plasma Cortisol Response: A Randomized Double-Blind Crossover Study. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:37701. [PMID: 33769847 PMCID: PMC7997608 DOI: 10.1289/ehp8923] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/19/2021] [Accepted: 03/10/2021] [Indexed: 05/16/2023]
Affiliation(s)
- Errol M Thomson
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada
- Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Alain Filiatreault
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada
| | - Andrew Williams
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, Ontario, Canada
| | - Christopher F Rider
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Chris Carlsten
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
- School of Population and Public Health, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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Thomson EM, Christidis T, Pinault L, Tjepkema M, Colman I, Crouse DL, van Donkelaar A, Martin RV, Hystad P, Robichaud A, Ménard R, Brook JR, Burnett RT. Self-rated stress, distress, mental health, and health as modifiers of the association between long-term exposure to ambient pollutants and mortality. ENVIRONMENTAL RESEARCH 2020; 191:109973. [PMID: 32810502 DOI: 10.1016/j.envres.2020.109973] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Individual and neighbourhood-scale socioeconomic characteristics modify associations between exposure to air pollution and mortality. The role of stress, which may integrate effects of social and environmental exposures on health, is unknown. We examined whether an individual's perspective on their own well-being, as assessed using self-rated measures of stress and health, modifies the pollutant-mortality relationship. METHODS The Canadian Community Health Survey (CCHS)-mortality cohort includes respondents from surveys administered between 2001 and 2012 linked to vital statistics and postal codes from 1981 until 2016. Annual fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) exposure estimates were attached to a sample of cohort members aged 30-89 years (n = 398,300 respondents/3,848,400 person-years). We examined whether self-rated stress, distress, mental health, and general health modified associations between long-term exposure to each pollutant (three-year moving average with one-year lag) and non-accidental mortality using Cox survival models, adjusted for individual- (i.e. socioeconomic and behavioural) and neighbourhood-scale covariates. RESULTS In fully-adjusted models, the relationship between exposure to pollutants and mortality was stronger among those with poor self-rated mental health, including a significant difference for NO2 (hazard ratio (HR) = 1.15, 95% CI 1.06-1.25 per IQR) compared to those with very good/excellent mental health (HR = 1.05, 95% CI 1.01-1.08; Cochran's Q = 4.01; p < 0.05). Poor self-rated health was similarly associated with higher pollutant-associated HRs, but only in unadjusted models. Stress and distress did not modify pollutant-mortality associations. CONCLUSIONS Poor self-rated mental and general health were associated with increased mortality attributed to exposure to ambient pollutants.
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Affiliation(s)
- Errol M Thomson
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, ON, Canada.
| | | | - Lauren Pinault
- Health Analysis Division, Statistics Canada, Ottawa, ON, Canada
| | | | - Ian Colman
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON, Canada
| | | | - Aaron van Donkelaar
- Department of Physics & Atmospheric Science, Dalhousie University, Halifax, NS, Canada; Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, MO, USA
| | - Randall V Martin
- Department of Physics & Atmospheric Science, Dalhousie University, Halifax, NS, Canada; Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, MO, USA; Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA
| | - Perry Hystad
- College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA
| | - Alain Robichaud
- Air Quality Research Division, Environment and Climate Change Canada, Dorval, QC, Canada
| | - Richard Ménard
- Air Quality Research Division, Environment and Climate Change Canada, Dorval, QC, Canada
| | - Jeffrey R Brook
- Dalla Lana School of Public Health, University of Toronto, ON, Canada
| | - Richard T Burnett
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada
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Thomson EM. Air Pollution, Stress, and Allostatic Load: Linking Systemic and Central Nervous System Impacts. J Alzheimers Dis 2020; 69:597-614. [PMID: 31127781 PMCID: PMC6598002 DOI: 10.3233/jad-190015] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Air pollution is a risk factor for cardiovascular and respiratory morbidity and mortality. A growing literature also links exposure to diverse air pollutants (e.g., nanoparticles, particulate matter, ozone, traffic-related air pollution) with brain health, including increased incidence of neurological and psychiatric disorders such as cognitive decline, dementia (including Alzheimer’s disease), anxiety, depression, and suicide. A critical gap in our understanding of adverse impacts of pollutants on the central nervous system (CNS) is the early initiating events triggered by pollutant inhalation that contribute to disease progression. Recent experimental evidence has shown that particulate matter and ozone, two common pollutants with differing characteristics and reactivity, can activate the hypothalamic-pituitary-adrenal (HPA) axis and release glucocorticoid stress hormones (cortisol in humans, corticosterone in rodents) as part of a neuroendocrine stress response. The brain is highly sensitive to stress: stress hormones affect cognition and mental health, and chronic stress can produce profound biochemical and structural changes in the brain. Chronic activation and/or dysfunction of the HPA axis also increases the burden on physiological stress response systems, conceptualized as allostatic load, and is a common pathway implicated in many diseases. The present paper provides an overview of how systemic stress-dependent biological responses common to particulate matter and ozone may provide insight into early CNS effects of pollutants, including links with oxidative, inflammatory, and metabolic processes. Evidence of pollutant effect modification by non-chemical stressors (e.g., socioeconomic position, psychosocial, noise), age (prenatal to elderly), and sex will also be reviewed in the context of susceptibility across the lifespan.
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Affiliation(s)
- Errol M Thomson
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, ON, Canada
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Bailey MJ, Naik NN, Wild LE, Patterson WB, Alderete TL. Exposure to air pollutants and the gut microbiota: a potential link between exposure, obesity, and type 2 diabetes. Gut Microbes 2020; 11:1188-1202. [PMID: 32347153 PMCID: PMC7524284 DOI: 10.1080/19490976.2020.1749754] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Work has shown that increased exposure to air pollutants independently contributes to obesity and type 2 diabetes risk, yet the exact mechanisms underlying these associations have not been fully characterized. The current review summarizes recent findings regarding the impact of inhaled and ingested air pollutants on the gut microbiota. Animal and human studies provide evidence that air pollutants, such as particulate matter, nitrogen oxides, and ozone, have the potential to alter the gut microbiota. Further, studies suggest that such exposure-induced alterations to the gut microbiota may contribute to increased risk for obesity and type 2 diabetes through inflammatory pathways. Future work is needed to fully understand the complex interactions between air pollution, the gut microbiome, and human health. Additionally, advanced sequencing methods for gut microbiome research present unique opportunities to study the underlying pathways that link increased air pollution exposure with obesity and type 2 diabetes risk.
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Affiliation(s)
- Maximillian J. Bailey
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Noopur N. Naik
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Laura E. Wild
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - William B. Patterson
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA
| | - Tanya L. Alderete
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO, USA,CONTACT Tanya L. Alderete University of Colorado Boulder, Department of Integrative Physiology, Ramaley Biology Building, 1800 Colorado Avenue, N379, Boulder, CO80309
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Rose M, Filiatreault A, Guénette J, Williams A, Thomson EM. Ozone increases plasma kynurenine-tryptophan ratio and impacts hippocampal serotonin receptor and neurotrophic factor expression: Role of stress hormones. ENVIRONMENTAL RESEARCH 2020; 185:109483. [PMID: 32278163 DOI: 10.1016/j.envres.2020.109483] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 06/11/2023]
Abstract
Air pollution is associated with adverse impacts on the brain, including cognitive decline and increased incidence of dementia, depression and anxiety; however, underlying mechanisms remain unclear. We have shown that both ozone and particulate matter activate the hypothalamic-pituitary-adrenal (HPA) axis, increasing plasma glucocorticoids and altering mRNA profiles in multiple tissues including the brain. HPA axis dysregulation has been associated with central nervous system impacts, including key effects in the hippocampus; accordingly, we hypothesized that pollutant-dependent increases in glucocorticoid levels impact biological pathways relevant to brain health. Fischer-344 rats were treated with metyrapone (0 or 50 mg/kg), a glucocorticoid synthesis inhibitor, and exposed to ozone (0 or 0.8 ppm) for 4 h (n = 5/group) to investigate the role of glucocorticoids in ozone-dependent effects on tryptophan metabolism and expression of serotonin receptors and neurotrophic factors. Ozone increased plasma levels of the tryptophan metabolite kynurenine (~2-fold) and decreased tryptophan levels (~1.2 fold). Hippocampal expression of serotonin receptors exhibited differential regulation following exposure, and expression of key neurotrophic factors (brain-derived neurotrophic factor, vascular endothelial growth factor A, insulin-like growth factor-1, tyrosine kinase receptor B, b-cell lymphoma 2) was decreased. Some, but not all effects were abrogated by metyrapone treatment, suggesting both glucocorticoid-dependent and -independent regulation. Exposure to exogenous corticosterone (10 mg/kg) followed by clean air reproduced the ozone effects that were blocked with metyrapone, confirming the specificity of effects to glucocorticoids. These results indicate that ozone can modify pathways relevant to brain health and establish a role for the HPA axis in mediating these effects.
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Affiliation(s)
- Mercedes Rose
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, K1A 0K9, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, K1H 8M5, Canada
| | - Alain Filiatreault
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, K1A 0K9, Canada
| | - Josée Guénette
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, K1A 0K9, Canada
| | - Andrew Williams
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, K1A 0K9, Canada
| | - Errol M Thomson
- Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, Ottawa, K1A 0K9, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, K1H 8M5, Canada.
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Fouladi F, Bailey MJ, Patterson WB, Sioda M, Blakley IC, Fodor AA, Jones RB, Chen Z, Kim JS, Lurmann F, Martino C, Knight R, Gilliland FD, Alderete TL. Air pollution exposure is associated with the gut microbiome as revealed by shotgun metagenomic sequencing. ENVIRONMENT INTERNATIONAL 2020; 138:105604. [PMID: 32135388 PMCID: PMC7181344 DOI: 10.1016/j.envint.2020.105604] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 05/17/2023]
Abstract
Animal work indicates exposure to air pollutants may alter the composition of the gut microbiota. This study examined relationships between air pollutants and the gut microbiome in young adults residing in Southern California. Our results demonstrate significant associations between exposure to air pollutants and the composition of the gut microbiome using whole-genome sequencing. Higher exposure to 24-hour O3 was associated with lower Shannon diversity index, higher Bacteroides caecimuris, and multiple gene pathways, including L-ornithine de novo biosynthesis as well as pantothenate and coenzyme A biosynthesis I. Among other pollutants, higher NO2 exposure was associated with fewer taxa, including higher Firmicutes. The percent variation in gut bacterial composition that was explained by air pollution exposure was up to 11.2% for O3 concentrations, which is large compared to the effect size for many other covariates reported in healthy populations. This study provides the first evidence of significant associations between exposure to air pollutants and the compositional and functional profile of the human gut microbiome. These results identify O3 as an important pollutant that may alter the human gut microbiome.
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Affiliation(s)
- Farnaz Fouladi
- University of North Carolina at Charlotte, Charlotte, NC, USA
| | | | | | - Michael Sioda
- University of North Carolina at Charlotte, Charlotte, NC, USA
| | - Ivory C Blakley
- University of North Carolina at Charlotte, Charlotte, NC, USA
| | - Anthony A Fodor
- University of North Carolina at Charlotte, Charlotte, NC, USA
| | | | - Zhanghua Chen
- University of Southern California, Los Angeles, CA, USA
| | | | | | - Cameron Martino
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, USA; Bioinformatics and Systems Biology Program, University of California San Diego, La Jolla, CA, USA
| | - Rob Knight
- Center for Microbiome Innovation, University of California San Diego, La Jolla, CA, USA; Department of Computer Science and Engineering, University of California San Diego, La Jolla, CA, USA; Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
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Kodavanti UP. Susceptibility Variations in Air Pollution Health Effects: Incorporating Neuroendocrine Activation. Toxicol Pathol 2019; 47:962-975. [PMID: 31594484 PMCID: PMC9353182 DOI: 10.1177/0192623319878402] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
Diverse host factors/phenotypes may exacerbate or diminish biological responses induced by air pollutant exposure. We lack an understanding of biological indicators of environmental exposures that culminate in a physiological response versus those that lead to adversity. Variations in response phenotype might arise centrally and/or at the local tissue level. In addition to genetic differences, the current evidence supports the roles of preexisting cardiopulmonary diseases, diabetes, diet, adverse prenatal environments, neurobehavioral disorders, childhood infections, microbiome, sex, and psychosocial stressors in modifying the susceptibility to air pollutant exposures. Animal models of human diseases, obesity, nutritional inadequacies, and neurobehavioral conditions have been compared with healthy controls to understand the causes of variations in susceptibility. Although psychosocial stressors have been associated with increased susceptibility to air pollutant effects, the contribution of neuroendocrine stress pathways in mediating these effects is just emerging. The new findings of neuroendocrine activation leading to systemic metabolic and immunological effects of air pollutants, and the potential contribution to allostatic load, emphasize the consideration of these mechanisms into susceptibility. Variations in susceptibility to air pollution health effects are likely to underlie host genetic and physiological conditions in concert with disrupted neuroendocrine circuitry that alters physiological stability under the influence of stressors.
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Affiliation(s)
- Urmila P Kodavanti
- Environmental Public Health Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
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Mumby S, Chung KF, Adcock IM. Transcriptional Effects of Ozone and Impact on Airway Inflammation. Front Immunol 2019; 10:1610. [PMID: 31354743 PMCID: PMC6635463 DOI: 10.3389/fimmu.2019.01610] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 06/27/2019] [Indexed: 12/24/2022] Open
Abstract
Epidemiological and challenge studies in healthy subjects and in individuals with asthma highlight the health impact of environmental ozone even at levels considered safe. Acute ozone exposure in man results in sputum neutrophilia in 30% of subjects particularly young children, females, and those with ongoing cardiopulmonary disease. This may be associated with systemic inflammation although not in all cases. Chronic exposure amplifies these effects and can result in the formation of asthma-like symptoms and immunopathology. Asthmatic patients who respond to ozone (responders) induce a greater number of genes in bronchoalveolar (BAL) macrophages than healthy responders with up-regulation of inflammatory and immune pathways under the control of cytokines and chemokines and the enhanced expression of remodeling and repair programmes including those associated with protease imbalances and cell-cell adhesion. These pathways are under the control of several key transcription regulatory factors including nuclear factor (NF)-κB, anti-oxidant factors such as nuclear factor (erythroid-derived 2)-like 2 NRF2, the p38 mitogen activated protein kinase (MAPK), and priming of the immune system by up-regulating toll-like receptor (TLR) expression. Murine and cellular models of acute and chronic ozone exposure recapitulate the inflammatory effects seen in humans and enable the elucidation of key transcriptional pathways. These studies emphasize the importance of distinct transcriptional networks in driving the detrimental effects of ozone. Studies indicate the critical role of mediators including IL-1, IL-17, and IL-33 in driving ozone effects on airway inflammation, remodeling and hyperresponsiveness. Transcription analysis and proof of mechanisms studies will enable the development of drugs to ameliorate the effects of ozone exposure in susceptible individuals.
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Affiliation(s)
- Sharon Mumby
- Respiratory Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Kian Fan Chung
- Respiratory Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Ian M Adcock
- Respiratory Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom
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