RESUMEN
Despite reported health benefits of urban greenspace (gs), the epidemiological evidence is less clear for allergic disease. To address a limitation of previous research, we examined the associations of medium- and high-resolution residential gs measures and tree and/or grass canopies with allergic outcomes for children enrolled in the longitudinal cincinnati childhood allergy and air pollution study (ccaaps). We estimated residential gs based on 400â¯m radial buffers around participant addresses (nâ¯=â¯478) using the normalized differential vegetation index (ndvi) and land cover-derived urban greenspace (ugs) (tree and grass coverage, combined and separate) at 30â¯m and 1.5-2.5â¯m resolution, respectively. Associations between outdoor aeroallergen sensitization and allergic rhinitis at age 7 and residential gs measures at different exposure windows were examined using multivariable logistic regression models. A 10% increase in ugs-derived grass coverage was associated with an increased risk of sensitization to grass pollens (adjusted odds ratio [aor]: 1.27; 95% confidence intervalâ¯=â¯1.02-1.58). For each 10% increase in ugs-derived tree canopy coverage, nonstatistically significant decreased odds were found for grass pollen sensitization, tree pollen sensitization, and sensitization to either (aor rangeâ¯=â¯0.87-0.94). Results similar in magnitude to ugs-tree canopy coverage were detected for ndvi and allergic sensitizations. High-resolution (down to 1.5â¯m) gs measures of grass- and tree-covered areas showed associations in opposite directions for different allergy outcomes. These data suggest that measures strongly correlated with tree canopy (e.g., ndvi) may be insufficient to detect health effects associated with proximity to different types of vegetation or help elucidate mechanisms related to specific gs exposure pathways.
Asunto(s)
Contaminación del Aire/estadística & datos numéricos , Alérgenos/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Rinitis Alérgica/epidemiología , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Oportunidad Relativa , Polen , Desarrollo Sostenible/tendencias , ÁrbolesRESUMEN
BACKGROUND: Recent literature suggests that children who are vitamin D deficient are uniquely susceptible to the effects of traffic-related air pollution (TRAP) exposure. This is highly significant because large segments of the population reside in zones of high TRAP exposure. OBJECTIVE: We sought to determine whether vitamin D supplementation mitigates the effect of TRAP exposure on asthma development, asthma exacerbation, and/or airway inflammation and to determine the timing of vitamin D supplementation that confers maximal health benefit. METHODS: Using established mouse models of asthma, we examined the effect of prenatal and postnatal vitamin D supplementation on asthma development, as well as the utility of vitamin D as a treatment for established asthma in the context of diesel exhaust particle (DEP) exposure. RESULTS: DEP and allergen coexposure resulted in increased airway hyperresponsiveness (AHR) and accumulation of pathogenic TH2/TH17 cells in the lungs of vitamin D-deficient mice compared with control mice. Prenatal and postnatal vitamin D supplementation significantly attenuated the development of AHR and decreased pulmonary accumulation of TH2/TH17 cells after coexposure to TRAP and allergen but not to allergen alone. Restoration of normal vitamin D status had no effect on AHR once asthma was already established. CONCLUSIONS: Our data establish that vitamin D confers protection against asthma development specifically in the context of TRAP exposure. Although vitamin D replacement did not reverse established asthma, restoration of normal vitamin D status in early life significantly attenuated the development of AHR in the setting of DEP-exacerbated allergic asthma and reduced numbers of lung TH2/TH17 cells, which portend the development of severe asthma.
Asunto(s)
Asma , Pulmón , Células Th17 , Células Th2 , Contaminación por Tráfico Vehicular/efectos adversos , Emisiones de Vehículos/toxicidad , Vitamina D/farmacología , Animales , Asma/inducido químicamente , Asma/inmunología , Asma/patología , Asma/prevención & control , Modelos Animales de Enfermedad , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Células Th17/inmunología , Células Th17/patología , Células Th2/inmunología , Células Th2/patologíaRESUMEN
Atopic dermatitis (AD) is a complex multifactorial inflammatory skin disease that affects ~280 million people worldwide. About 85% of AD cases begin in childhood, a significant portion of which can persist into adulthood. Moreover, a typical progression of children with AD to food allergy, asthma or allergic rhinitis has been reported ("allergic march" or "atopic march"). AD comprises highly heterogeneous sub-phenotypes/endotypes resulting from complex interplay between intrinsic and extrinsic factors, such as environmental stimuli, and genetic factors regulating cutaneous functions (impaired barrier function, epidermal lipid, and protease abnormalities), immune functions and the microbiome. Though the roles of high-throughput "omics" integrations in defining endotypes are recognized, current analyses are primarily based on individual omics data and using binary clinical outcomes. Although individual omics analysis, such as genome-wide association studies (GWAS), can effectively map variants correlated with AD, the majority of the heritability and the functional relevance of discovered variants are not explained or known by the identified variants. The limited success of singular approaches underscores the need for holistic and integrated approaches to investigate complex phenotypes using trans-omics data integration strategies. Integrating omics layers (e.g., genome, epigenome, transcriptome, proteome, metabolome, lipidome, exposome, microbiome), which often have complementary and synergistic effects, might provide the opportunity to capture the flow of information underlying AD disease manifestation. Overlapping genes/candidates derived from multiple omics types include FLG, SPINK5, S100A8, and SERPINB3 in AD pathogenesis. Overlapping pathways include macrophage, endothelial cell and fibroblast activation pathways, in addition to well-known Th1/Th2 and NFkB activation pathways. Interestingly, there was more multi-omics overlap at the pathway level than gene level. Further analysis of multi-omics overlap at the tissue level showed that among 30 tissue types from the GTEx database, skin and esophagus were significantly enriched, indicating the biological interconnection between AD and food allergy. The present work explores multi-omics integration and provides new biological insights to better define the biological basis of AD etiology and confirm previously reported AD genes/pathways. In this context, we also discuss opportunities and challenges introduced by "big omics data" and their integration.