Browsing by Subject "Asthma"
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Item Open Access A Heterotopic Xenograft Model of Human Airways for Investigating Fibrosis in Asthma.(American journal of respiratory cell and molecular biology, 2017-03) Hackett, Tillie-Louise; Ferrante, Sarah C; Hoptay, Claire E; Engelhardt, John F; Ingram, Jennifer L; Zhang, Yulong; Alcala, Sarah E; Shaheen, Furquan; Matz, Ethan; Pillai, Dinesh K; Freishtat, Robert JLimited in vivo models exist to investigate the lung airway epithelial role in repair, regeneration, and pathology of chronic lung diseases. Herein, we introduce a novel animal model in asthma-a xenograft system integrating a differentiating human asthmatic airway epithelium with an actively remodeling rodent mesenchyme in an immunocompromised murine host. Human asthmatic and nonasthmatic airway epithelial cells were seeded into decellularized rat tracheas. Tracheas were ligated to a sterile cassette and implanted subcutaneously in the flanks of nude mice. Grafts were harvested at 2, 4, or 6 weeks for tissue histology, fibrillar collagen, and transforming growth factor-β activation analysis. We compared immunostaining in these xenografts to human lungs. Grafted epithelial cells generated a differentiated epithelium containing basal, ciliated, and mucus-expressing cells. By 4 weeks postengraftment, asthmatic epithelia showed decreased numbers of ciliated cells and decreased E-cadherin expression compared with nonasthmatic grafts, similar to human lungs. Grafts seeded with asthmatic epithelial cells had three times more fibrillar collagen and induction of transforming growth factor-β isoforms at 6 weeks postengraftment compared with nonasthmatic grafts. Asthmatic epithelium alone is sufficient to drive aberrant mesenchymal remodeling with fibrillar collagen deposition in asthmatic xenografts. Moreover, this xenograft system represents an advance over current asthma models in that it permits direct assessment of the epithelial-mesenchymal trophic unit.Item Open Access A novel role for primary cilia in airway remodeling.(American journal of physiology. Lung cellular and molecular physiology, 2017-08) Trempus, Carol S; Song, Weifeng; Lazrak, Ahmed; Yu, Zhihong; Creighton, Judy R; Young, Bethany M; Heise, Rebecca L; Yu, Yen Rei; Ingram, Jennifer L; Tighe, Robert M; Matalon, Sadis; Garantziotis, StavrosPrimary cilia (PC) are solitary cellular organelles that play critical roles in development, homeostasis, and disease pathogenesis by modulating key signaling pathways such as Sonic Hedgehog and calcium flux. The antenna-like shape of PC enables them also to facilitate sensing of extracellular and mechanical stimuli into the cell, and a critical role for PC has been described for mesenchymal cells such as chondrocytes. However, nothing is known about the role of PC in airway smooth muscle cells (ASMCs) in the context of airway remodeling. We hypothesized that PC on ASMCs mediate cell contraction and are thus integral in the remodeling process. We found that PC are expressed on ASMCs in asthmatic lungs. Using pharmacological and genetic methods, we demonstrated that PC are necessary for ASMC contraction in a collagen gel three-dimensional model both in the absence of external stimulus and in response to the extracellular component hyaluronan. Mechanistically, we demonstrate that the effect of PC on ASMC contraction is, to a small extent, due to their effect on Sonic Hedgehog signaling and, to a larger extent, due to their effect on calcium influx and membrane depolarization. In conclusion, PC are necessary for the development of airway remodeling by mediating calcium flux and Sonic Hedgehog signaling.Item Open Access Airway fibroblasts in asthma manifest an invasive phenotype.(American journal of respiratory and critical care medicine, 2011-06) Ingram, Jennifer L; Huggins, Molly J; Church, Tony D; Li, Yuejuan; Francisco, Dave C; Degan, Simone; Firszt, Rafael; Beaver, Denise M; Lugogo, Njira L; Wang, Ying; Sunday, Mary E; Noble, Paul W; Kraft, MonicaRationale
Invasive cell phenotypes have been demonstrated in malignant transformation, but not in other diseases, such as asthma. Cellular invasiveness is thought to be mediated by transforming growth factor (TGF)-β1 and matrix metalloproteinases (MMPs). IL-13 is a key T(H)2 cytokine that directs many features of airway remodeling through TGF-β1 and MMPs.Objectives
We hypothesized that, in human asthma, IL-13 stimulates increased airway fibroblast invasiveness via TGF-β1 and MMPs in asthma compared with normal controls.Methods
Fibroblasts were cultured from endobronchial biopsies in 20 subjects with mild asthma (FEV(1): 90 ± 3.6% pred) and 17 normal control subjects (FEV(1): 102 ± 2.9% pred) who underwent bronchoscopy. Airway fibroblast invasiveness was investigated using Matrigel chambers. IL-13 or IL-13 with TGF-β1 neutralizing antibody or pan-MMP inhibitor (GM6001) was added to the lower chamber as a chemoattractant. Flow cytometry and immunohistochemistry were performed in a subset of subjects to evaluate IL-13 receptor levels.Measurements and main results
IL-13 significantly stimulated invasion in asthmatic airway fibroblasts, compared with normal control subjects. Inhibitors of both TGF-β1 and MMPs blocked IL-13-induced invasion in asthma, but had no effect in normal control subjects. At baseline, in airway tissue, IL-13 receptors were expressed in significantly higher levels in asthma, compared with normal control subjects. In airway fibroblasts, baseline IL-13Rα2 was reduced in asthma compared with normal control subjects.Conclusions
IL-13 potentiates airway fibroblast invasion through a mechanism involving TGF-β1 and MMPs. IL-13 receptor subunits are differentially expressed in asthma. These effects may result in IL-13-directed airway remodeling in asthma.Item Open Access Analysis of DNA methylation at birth and in childhood reveals changes associated with season of birth and latitude.(Clinical epigenetics, 2023-09) Kadalayil, Latha; Alam, Md Zahangir; White, Cory Haley; Ghantous, Akram; Walton, Esther; Gruzieva, Olena; Merid, Simon Kebede; Kumar, Ashish; Roy, Ritu P; Solomon, Olivia; Huen, Karen; Eskenazi, Brenda; Rzehak, Peter; Grote, Veit; Langhendries, Jean-Paul; Verduci, Elvira; Ferre, Natalia; Gruszfeld, Darek; Gao, Lu; Guan, Weihua; Zeng, Xuehuo; Schisterman, Enrique F; Dou, John F; Bakulski, Kelly M; Feinberg, Jason I; Soomro, Munawar Hussain; Pesce, Giancarlo; Baiz, Nour; Isaevska, Elena; Plusquin, Michelle; Vafeiadi, Marina; Roumeliotaki, Theano; Langie, Sabine AS; Standaert, Arnout; Allard, Catherine; Perron, Patrice; Bouchard, Luigi; van Meel, Evelien R; Felix, Janine F; Jaddoe, Vincent WV; Yousefi, Paul D; Ramlau-Hansen, Cecilia H; Relton, Caroline L; Tobi, Elmar W; Starling, Anne P; Yang, Ivana V; Llambrich, Maria; Santorelli, Gillian; Lepeule, Johanna; Salas, Lucas A; Bustamante, Mariona; Ewart, Susan L; Zhang, Hongmei; Karmaus, Wilfried; Röder, Stefan; Zenclussen, Ana Claudia; Jin, Jianping; Nystad, Wenche; Page, Christian M; Magnus, Maria; Jima, Dereje D; Hoyo, Cathrine; Maguire, Rachel L; Kvist, Tuomas; Czamara, Darina; Räikkönen, Katri; Gong, Tong; Ullemar, Vilhelmina; Rifas-Shiman, Sheryl L; Oken, Emily; Almqvist, Catarina; Karlsson, Robert; Lahti, Jari; Murphy, Susan K; Håberg, Siri E; London, Stephanie; Herberth, Gunda; Arshad, Hasan; Sunyer, Jordi; Grazuleviciene, Regina; Dabelea, Dana; Steegers-Theunissen, Régine PM; Nohr, Ellen A; Sørensen, Thorkild IA; Duijts, Liesbeth; Hivert, Marie-France; Nelen, Vera; Popovic, Maja; Kogevinas, Manolis; Nawrot, Tim S; Herceg, Zdenko; Annesi-Maesano, Isabella; Fallin, M Daniele; Yeung, Edwina; Breton, Carrie V; Koletzko, Berthold; Holland, Nina; Wiemels, Joseph L; Melén, Erik; Sharp, Gemma C; Silver, Matt J; Rezwan, Faisal I; Holloway, John WBackground
Seasonal variations in environmental exposures at birth or during gestation are associated with numerous adult traits and health outcomes later in life. Whether DNA methylation (DNAm) plays a role in the molecular mechanisms underlying the associations between birth season and lifelong phenotypes remains unclear.Methods
We carried out epigenome-wide meta-analyses within the Pregnancy And Childhood Epigenetic Consortium to identify associations of DNAm with birth season, both at differentially methylated probes (DMPs) and regions (DMRs). Associations were examined at two time points: at birth (21 cohorts, N = 9358) and in children aged 1-11 years (12 cohorts, N = 3610). We conducted meta-analyses to assess the impact of latitude on birth season-specific associations at both time points.Results
We identified associations between birth season and DNAm (False Discovery Rate-adjusted p values < 0.05) at two CpGs at birth (winter-born) and four in the childhood (summer-born) analyses when compared to children born in autumn. Furthermore, we identified twenty-six differentially methylated regions (DMR) at birth (winter-born: 8, spring-born: 15, summer-born: 3) and thirty-two in childhood (winter-born: 12, spring and summer: 10 each) meta-analyses with few overlapping DMRs between the birth seasons or the two time points. The DMRs were associated with genes of known functions in tumorigenesis, psychiatric/neurological disorders, inflammation, or immunity, amongst others. Latitude-stratified meta-analyses [higher (≥ 50°N), lower (< 50°N, northern hemisphere only)] revealed differences in associations between birth season and DNAm by birth latitude. DMR analysis implicated genes with previously reported links to schizophrenia (LAX1), skin disorders (PSORS1C, LTB4R), and airway inflammation including asthma (LTB4R), present only at birth in the higher latitudes (≥ 50°N).Conclusions
In this large epigenome-wide meta-analysis study, we provide evidence for (i) associations between DNAm and season of birth that are unique for the seasons of the year (temporal effect) and (ii) latitude-dependent variations in the seasonal associations (spatial effect). DNAm could play a role in the molecular mechanisms underlying the effect of birth season on adult health outcomes.Item Open Access Asthma medication usage is significantly reduced following bariatric surgery.(Surgical endoscopy, 2019-06) Guerron, Alfredo D; Ortega, Camila B; Lee, Hui-Jie; Davalos, Gerardo; Ingram, Jennifer; Portenier, DanaIntroduction
Asthma is an important healthcare problem affecting millions in the United States. Additionally, a large proportion of patients with asthma suffer from obesity. These patients exhibit poor asthma control and reduced therapy response, increasing utilization of healthcare resources. Pulmonary symptoms improve after bariatric surgery (BS), and we hypothesized that asthma medication usage would decrease following BS.Methods
A retrospective data analysis was performed in adult patients from a single institution's database. Patients with obesity using at least one asthma medication pre-operatively who underwent BS were studied for up to 3-years post-operation. Poisson generalized linear mixed models for repeated measures were used to evaluate the effects of time and procedure type on the number of asthma medication.Results
Bariatric patients with at least one prescribed asthma medication (mean 1.4 ± 0.6) were included (n = 751). The mean age at time of operation was 46.8 ± 11.6 years, mean weight was 295.9 ± 57 lbs, and mean body mass index (BMI) was 49 ± 8.2 kg/m2; 87.7% were female, 33.4% had diabetes, 44.2% used gastroesophageal reflux disease (GERD) medication, and 64.4% used hypertension medication. The most common procedure was Roux-en-Y gastric bypass (79%), followed by sleeve gastrectomy (10.7%), adjustable gastric banding (8.1%), and duodenal switch (2.3%). The mean number of prescribed asthma medications among all procedures decreased by 27% at 30 days post-operation (p < 0.0001), 37% at 6 months (p < 0.0001), 44% at 1 year (p < 0.0001), and 46% at 3 years (p < 0.0001) after adjusting for risk factors. No significant differences in medication use over time between procedure types were observed. In the adjusted analysis, the mean number of asthma medications was 12% higher in patients using at least one GERD medication (p = 0.015) and 8% higher with 10-unit increase in pre-operative BMI (p = 0.006).Conclusion
BS significantly decreases asthma medication use starting 30 days post-operation with a sustained reduction for up to 3 years.Item Open Access Asthma, Airflow Obstruction, and Eosinophilic Airway Inflammation Prevalence in Western Kenya: A Population-Based Cross-Sectional Study.(International journal of public health, 2023-01) Navuluri, Neelima; Lagat, David; Egger, Joseph R; Birgen, Elcy; Diero, Lameck; Murdoch, David M; Thielman, Nathan; Kussin, Peter S; Que, Loretta G; Paul, DevonObjectives: Determine the prevalence of airway disease (e.g., asthma, airflow obstruction, and eosinophilic airway inflammation) in Kenya, as well as related correlates of airway disease and health-related quality of life. Methods: A three-stage, cluster-randomized cross-sectional study in Uasin Gishu County, Kenya was conducted. Individuals 12 years and older completed questionnaires (including St. George's Respiratory Questionnaire for COPD, SGRQ-C), spirometry, and fractional exhaled nitric oxide (FeNO) testing. Prevalence ratios with 95% confidence intervals (CIs) were calculated. Multivariable models were used to assess correlates of airflow obstruction and high FeNO. Results: Three hundred ninety-two participants completed questionnaires, 369 completed FeNO testing, and 305 completed spirometry. Mean age was 37.5 years; 64% were women. The prevalence of asthma, airflow obstruction on spirometry, and eosinophilic airway inflammation was 21.7%, 12.3% and 15.7% respectively in the population. Women had significantly higher SGRQ-C scores compared to men (15.0 vs. 7.7). Wheezing or whistling in the last year and SGRQ-C scores were strongly associated with FeNO levels >50 ppb after adjusting for age, gender, BMI, and tobacco use. Conclusion: Airway disease is a significant health problem in Kenya affecting a young population who lack a significant tobacco use history.Item Open Access Beta-arrestin-2 regulates the development of allergic asthma.(J Clin Invest, 2003-08) Walker, Julia KL; Fong, Alan M; Lawson, Barbara L; Savov, Jordan D; Patel, Dhavalkumar D; Schwartz, David A; Lefkowitz, Robert JAsthma is a chronic inflammatory disorder of the airways that is coordinated by Th2 cells in both human asthmatics and animal models of allergic asthma. Migration of Th2 cells to the lung is key to their inflammatory function and is regulated in large part by chemokine receptors, members of the seven-membrane-spanning receptor family. It has been reported recently that T cells lacking beta-arrestin-2, a G protein-coupled receptor regulatory protein, demonstrate impaired migration in vitro. Here we show that allergen-sensitized mice having a targeted deletion of the beta-arrestin-2 gene do not accumulate T lymphocytes in their airways, nor do they demonstrate other physiological and inflammatory features characteristic of asthma. In contrast, the airway inflammatory response to LPS, an event not coordinated by Th2 cells, is fully functional in mice lacking beta-arrestin-2. beta-arrestin-2-deficient mice demonstrate OVA-specific IgE responses, but have defective macrophage-derived chemokine-mediated CD4+ T cell migration to the lung. This report provides the first evidence that beta-arrestin-2 is required for the manifestation of allergic asthma. Because beta-arrestin-2 regulates the development of allergic inflammation at a proximal step in the inflammatory cascade, novel therapies focused on this protein may prove useful in the treatment of asthma.Item Open Access Characteristics of primary care and rates of pediatric hospitalizations in Brazil.(Revista de saude publica, 2020-01) Lisboa, Lívia Anniele Sousa; Queiroz, Rejane Christine de Sousa; Thomaz, Erika Bárbara Abreu Fonseca; Silva, Núbia Cristina da; Rocha, Thiago Augusto Hernandes; Vissoci, João Ricardo Nickenig; Staton, Catherine Ann; Lein, Adriana; Simões, Vanda Maria Ferreira; Thumé, Elaine; Facchini, Luiz AugustoObjective
To evaluate the association among characteristics of primary health care center (PHCC) with hospitalizations for primary care sensitive conditions (PCSC) in Brazil.Method
In this study, a cross-sectional ecological study was performed. This study analyzed the 27 capitals of Brazil's federative units. Data were aggregated from the following open access databases: National Program for Access and Quality Improvement in Primary Care, the Hospital Information System of Brazilian Unified Health System and Annual Population Census conducted by the Brazilian Institute of Geography and Statistics. Associations were estimated among characteristics of primary care with the number of three PCSC as the leading causes of hospitalization in children under-5 population in Brazil: asthma, diarrhea, and pneumonia.Results
In general, PHCC showed limited structural adequacy (37.3%) for pediatric care in Brazil. The capitals in South and Southeast regions had the best structure whereas the North and Northeast had the worst. Fewer PCSC hospitalizations were significantly associated with PHCC which presented appropriate equipment (RR: 0.98; 95%CI: 0.97-0.99), structural conditions (RR: 0.98; 95%CI: 0.97-0.99), and signage/identification of professionals and facilities (RR: 0.98; 95%CI: 0.97-0.99). Higher PCSC hospitalizations were significantly associated with PHCC with more physicians (RR: 1.23, 95%CI: 1.02-1.48), it forms (RR: 1.01, 95%CI: 1.01-1.02), and more medications (RR: 1.02, 95%CI: 1.01-1.03).Conclusion
Infrastructural adequacy of PHCC was associated with less PCSC hospitalizations, while availability medical professional and medications were associated with higher PCSC hospitalizations.Item Open Access Cutting edge: distinct glycolytic and lipid oxidative metabolic programs are essential for effector and regulatory CD4+ T cell subsets.(J Immunol, 2011-03-15) Michalek, Ryan D; Gerriets, Valerie A; Jacobs, Sarah R; Macintyre, Andrew N; MacIver, Nancie J; Mason, Emily F; Sullivan, Sarah A; Nichols, Amanda G; Rathmell, Jeffrey CStimulated CD4(+) T lymphocytes can differentiate into effector T cell (Teff) or inducible regulatory T cell (Treg) subsets with specific immunological roles. We show that Teff and Treg require distinct metabolic programs to support these functions. Th1, Th2, and Th17 cells expressed high surface levels of the glucose transporter Glut1 and were highly glycolytic. Treg, in contrast, expressed low levels of Glut1 and had high lipid oxidation rates. Consistent with glycolysis and lipid oxidation promoting Teff and Treg, respectively, Teff were selectively increased in Glut1 transgenic mice and reliant on glucose metabolism, whereas Treg had activated AMP-activated protein kinase and were dependent on lipid oxidation. Importantly, AMP-activated protein kinase stimulation was sufficient to decrease Glut1 and increase Treg generation in an asthma model. These data demonstrate that CD4(+) T cell subsets require distinct metabolic programs that can be manipulated in vivo to control Treg and Teff development in inflammatory diseases.Item Open Access Development of a real-world database for asthma and COPD: The SingHealth-Duke-NUS-GSK COPD and Asthma Real-World Evidence (SDG-CARE) collaboration.(BMC medical informatics and decision making, 2023-01) Lam, Sean Shao Wei; Fang, Andrew Hao Sen; Koh, Mariko Siyue; Shantakumar, Sumitra; Yeo, See-Hwee; Matchar, David Bruce; Ong, Marcus Eng Hock; Poon, Ken Mei Ting; Huang, Liming; Harikrishan, Sudha; Milea, Dominique; Burke, Des; Webb, Dave; Ragavendran, Narayanan; Tan, Ngiap Chuan; Loo, Chian MinPurpose
The SingHealth-Duke-GlaxoSmithKline COPD and Asthma Real-world Evidence (SDG-CARE) collaboration was formed to accelerate the use of Singaporean real-world evidence in research and clinical care. A centerpiece of the collaboration was to develop a near real-time database from clinical and operational data sources to inform healthcare decision making and research studies on asthma and chronic obstructive pulmonary disease (COPD).Methods
Our multidisciplinary team, including clinicians, epidemiologists, data scientists, medical informaticians and IT engineers, adopted the hybrid waterfall-agile project management methodology to develop the SingHealth COPD and Asthma Data Mart (SCDM). The SCDM was developed within the organizational data warehouse. It pulls and maps data from various information systems using extract, transform and load (ETL) pipelines. Robust user testing and data verification was also performed to ensure that the business requirements were met and that the ETL pipelines were valid.Results
The SCDM includes 199 data elements relevant to asthma and COPD. Data verification was performed and found the SCDM to be reliable. As of December 31, 2019, the SCDM contained 36,407 unique patients with asthma and COPD across the spectrum from primary to tertiary care in our healthcare system. The database updates weekly to add new data of existing patients and to include new patients who fulfil the inclusion criteria.Conclusions
The SCDM was systematically developed and tested to support the use RWD for clinical and health services research in asthma and COPD. This can serve as a platform to provide research and operational insights to improve the care delivered to our patients.Item Open Access Effect of the S-nitrosoglutathione reductase inhibitor N6022 on bronchial hyperreactivity in asthma.(Immunity, inflammation and disease, 2018-06) Que, Loretta G; Yang, Zhonghui; Lugogo, Njira L; Katial, Rohit K; Shoemaker, Steven A; Troha, Janice M; Rodman, David M; Tighe, Robert M; Kraft, MonicaRationale
Patients with asthma demonstrate depletion of the endogenous bronchodilator GSNO and upregulation of GSNOR.Objectives
An exploratory proof of concept clinical study of N6022 in mild asthma to determine the potential bronchoprotective effects of GSNOR inhibition. Mechanistic studies aimed to provide translational evidence of effect.Methods
Fourteen mild asthma patients were treated with intravenous N6022 (5 mg) or placebo and observed for 7 days, with repeated assessments of the provocative dose of methacholine causing a 20% fall in FEV1 (methacholine PC20 FEV1), followed by a washout period and crossover treatment and observation. In vitro studies in isolated eosinophils investigated the effect of GSNO and N6022 on apoptosis.Measurements and main results
This was a negative trial as it failed to reach its primary endpoint, which was change from baseline in methacholine PC20 FEV1 at 24 h. However, our exploratory analysis demonstrated significantly more two dose-doubling increases in PC20 FEV1 for N6022 compared with placebo (21% vs 6%, P < 0.05) over the 7-day observation period. Furthermore, a significant treatment effect was observed in the change in PC20 FEV1 from baseline averaged over the 7-day observation period (mean change: +0.82 mg/ml [N6022] from 1.34 mg/ml [baseline] vs -0.18 mg/ml [placebo] from 1.16 mg/ml [baseline], P = 0.023). N6022 was well tolerated in mild asthmatics. In vitro studies demonstrated enhanced eosinophilic apoptosis with N6022.Conclusions
In this early phase exploratory proof of concept trial in asthma, N6022 did not significantly alter methacholine PC20 FEV1 at 24 h, but did have a treatment effect at 7 days compared to baseline. Further investigation of the efficacy of S-nitrosoglutathione reductase inhibition in a patient population with eosinophilic asthma is warranted.Item Open Access Exogenous leptin enhances markers of airway fibrosis in a mouse model of chronic allergic airways disease.(Respiratory research, 2022-05-24) Ihrie, Mark D; McQuade, Victoria L; Womble, Jack T; Hegde, Akhil; McCravy, Matthew S; Lacuesta, Cyrus Victor G; Tighe, Robert M; Que, Loretta G; Walker, Julia KL; Ingram, Jennifer LBackground
Asthma patients with comorbid obesity exhibit increased disease severity, in part, due to airway remodeling, which is also observed in mouse models of asthma and obesity. A mediator of remodeling that is increased in obesity is leptin. We hypothesized that in a mouse model of allergic airways disease, mice receiving exogenous leptin would display increased airway inflammation and fibrosis.Methods
Five-week-old male and female C57BL/6J mice were challenged with intranasal house dust mite (HDM) allergen or saline 5 days per week for 6 weeks (n = 6-9 per sex, per group). Following each HDM exposure, mice received subcutaneous recombinant human leptin or saline. At 48 h after the final HDM challenge, lung mechanics were evaluated and the mice were sacrificed. Bronchoalveolar lavage was performed and differential cell counts were determined. Lung tissue was stained with Masson's trichrome, periodic acid-Schiff, and hematoxylin and eosin stains. Mouse lung fibroblasts were cultured, and whole lung mRNA was isolated.Results
Leptin did not affect mouse body weight, but HDM+leptin increased baseline blood glucose. In mixed-sex groups, leptin increased mouse lung fibroblast invasiveness and increased lung Col1a1 mRNA expression. Total lung resistance and tissue damping were increased with HDM+leptin treatment, but not leptin or HDM alone. Female mice exhibited enhanced airway responsiveness to methacholine with HDM+leptin treatment, while leptin alone decreased total respiratory system resistance in male mice.Conclusions
In HDM-induced allergic airways disease, administration of exogenous leptin to mice enhanced lung resistance and increased markers of fibrosis, with differing effects between males and females.Item Open Access Exploring Associations Between Prenatal PFAS Exposure and Childhood Asthma(2021-04-28) Bogar, LanePer- and polyfluoroalkyl substances (PFAS) are a large class of man-made chemicals used extensively in consumer and industrial products, making them ubiquitous in the built and natural environment. These chemicals pose a cause for concern, as there is increasing experimental and epidemiological evidence suggesting that exposure is associated with adverse health outcomes, especially prenatal PFAS exposure during critical periods of development. This study explored the associations between prenatal PFAS exposure, measured via maternal serum levels collected during pregnancy, and childhood asthma incidence in a cohort of 155 women, and 165 of their children from North Carolina. PFAS were detected in all serum samples and levels were similar to those in the general population. Statistical analyses incorporated potential predictors and covariates, including sex, age and race. After adjusting for these factors, statistically significant associations with asthma were found. Future efforts are needed to examine prenatal PFAS exposures and respiratory outcomes in later life.Item Open Access Factors Related to Biologic Adherence and Outcomes Among Moderate-to-Severe Asthma Patients.(The journal of allergy and clinical immunology. In practice, 2022-09) Osazuwa-Peters, Oyomoare L; Greiner, Melissa A; Oberle, Amber; Oakes, Megan; Thomas, Sheila M; Bosworth, HaydenBackground
Adherence barriers to asthma biologics may not be uniform across administration settings for patients with moderate-to-severe asthma.Objective
To examine differences in asthma biologic adherence and associated factors, as well as association with a 1-year all-cause emergency department (ED) visit, across administration settings.Methods
A retrospective study of biologic naïve moderate-to-severe asthma patients with initial biologic therapy between January 1, 2016, and April 30, 2020, in the Optum Clinformatics Data Mart was performed. Three administration settings were identified: Clinic-only (outpatient office/infusion center), Home (self-administration), and Hybrid setting (mixture of clinic and self-administration). Asthma biologic adherence was the proportion of observed over expected biologic dose administrations received within 6 months from initial therapy. Factors associated with adherence were identified by administration setting, using Poisson regression analyses. A relationship between a 1-year all-cause ED visit and adherence was assessed for each administration setting using Cox regression analyses.Results
The study cohort was 3932 patients. Biologics adherence was 0.75 [0.5, 1] in Clinic setting, the most common administration setting, and 0.83 [0.5, 1] in both Home and Hybrid settings. Specialist access was consistently associated with better biologic adherence, whereas Black race, Hispanic ethnicity, lower education, Medicare only insurance, and higher patient out-of-pocket cost were associated with worse biologic adherence in some settings. In the Hybrid setting, hazard for a 1-year all-cause ED visit decreased with biologic adherence.Conclusions
Asthma biologic adherence varied by administration setting. Efforts to improve asthma biologic adherence should consider promoting self-administration when beneficial, improving prior specialist access, and targeting patients with higher risk of suboptimal adherence particularly Black and Hispanic patients.Item Open Access Give Me Some Room to Breathe! Can Targeting SPHK2 Reduce Airway Smooth Muscle Thickening in Asthma?(American journal of respiratory cell and molecular biology, 2020-01) Ingram, Jennifer LItem Open Access IL-13 in asthma and allergic disease: asthma phenotypes and targeted therapies.(The Journal of allergy and clinical immunology, 2012-10) Ingram, Jennifer L; Kraft, MonicaDecades of research in animal models have provided abundant evidence to show that IL-13 is a key T(H)2 cytokine that directs many of the important features of airway inflammation and remodeling in patients with allergic asthma. Several promising focused therapies for asthma that target the IL-13/IL-4/signal transducer and activator of transcription 6 pathway are in development, including anti-IL-13 mAbs and IL-4 receptor antagonists. The efficacy of these new potential asthma therapies depends on the responsiveness of patients. However, an understanding of how IL-13-directed therapies might benefit asthmatic patients is confounded by the complex heterogeneity of the disease. Recent efforts to classify subphenotypes of asthma have focused on sputum cellular inflammation profiles, as well as cluster analyses of clinical variables and molecular and genetic signatures. Researchers and clinicians can now evaluate biomarkers of T(H)2-driven airway inflammation in asthmatic patients, such as serum IgE levels, sputum eosinophil counts, fraction of exhaled nitric oxide levels, and serum periostin levels, to aid decision making in clinical trials and drug development and to identify subsets of patients who might benefit from therapies. Although it is unlikely that these therapies will benefit all asthmatic patients with this heterogeneous disease, advances in understanding asthma subphenotypes in relation to clinical variables and T(H)2 cytokine responses offer the opportunity to improve the efficacy and safety of proposed therapies for asthma.Item Open Access Improving the Efficiency of Care for Pediatric Patients Hospitalized With Asthma.(Hospital pediatrics, 2017-01) Bartlett, Kathleen W; Parente, Victoria M; Morales, Vanessa; Hauser, Jillian; McLean, Heather SAsthma exacerbations are a leading cause of hospitalization among children. Despite the existence of national pediatric asthma guidelines, significant variation in care persists. At Duke Children's Hospital, we determined that our average length of stay (ALOS) and cost for pediatric asthma admissions exceeded that of our peers. Our aim was to reduce the ALOS of pediatric patients hospitalized with asthma from 2.9 days to 2.6 days within 12 months by implementing an asthma pathway within our new electronic health record.We convened a multidisciplinary committee charged with reducing variability in practice, ALOS, and cost of inpatient pediatric asthma care, while adhering to evidence-based guidelines. Interventions were tested through multiple "plan-do-study-act" cycles. Control charts of the ALOS were constructed and annotated with interventions, including testing of an asthma score, implementation of order sets, use of a respiratory therapy-driven albuterol treatment protocol, and provision of targeted education. Order set usage was audited as a process measure. Readmission rates were monitored as a balancing measure.The ALOS of pediatric patients hospitalized with asthma decreased significantly from 2.9 days to 2.3 days. Comparing baseline with intervention variable direct cost data revealed a savings of $1543 per case. Improvements occurred in the context of high compliance with the asthma pathway order sets. Readmission rates remained stable throughout the study period.Implementation of an asthma care pathway based on the electronic health record improved the efficiency and variable direct costs of hospital care, reduced variability in practice, and ensured adherence to high-quality national guidelines.Item Open Access Interleukin-13 induces collagen type-1 expression through matrix metalloproteinase-2 and transforming growth factor-β1 in airway fibroblasts in asthma.(The European respiratory journal, 2014-02) Firszt, Rafael; Francisco, Dave; Church, Tony D; Thomas, Joseph M; Ingram, Jennifer L; Kraft, MonicaAirway remodelling is a feature of asthma that contributes to loss of lung function. One of the central components of airway remodelling is subepithelial fibrosis. Interleukin (IL)-13 is a key T-helper 2 cytokine and is believed to be the central mediator of allergic asthma including remodelling, but the mechanism driving the latter has not been elucidated in human asthma. We hypothesised that IL-13 stimulates collagen type-1 production by the airway fibroblast in a matrix metalloproteinase (MMP)- and transforming growth factor (TGF)-β1-dependent manner in human asthma as compared to healthy controls. Fibroblasts were cultured from endobronchial biopsies in 14 subjects with mild asthma and 13 normal controls that underwent bronchoscopy. Airway fibroblasts were treated with various mediators including IL-13 and specific MMP-inhibitors. IL-13 significantly stimulated collagen type-1 production in asthma compared to normal controls. Inhibitors of MMP-2 significantly attenuated collagen production in asthma but had no effect in normal controls. IL-13 significantly increased total and active forms of TGF-β1, and this activation was blocked using an MMP-2 inhibitor. IL-13 activated endogenous MMP-2 in asthma patients as compared to normal controls. In an ex vivo model, IL-13 potentiates airway remodelling through a mechanism involving TGF-β1 and MMP-2. These effects provide insights into the mechanism involved in IL-13-directed airway remodelling in asthma.Item Open Access Is chronic asthma associated with shorter leukocyte telomere length at midlife?(Am J Respir Crit Care Med, 2014-08-15) Belsky, Daniel W; Shalev, Idan; Sears, Malcolm R; Hancox, Robert J; Lee Harrington, Hona; Houts, Renate; Moffitt, Terrie E; Sugden, Karen; Williams, Benjamin; Poulton, Richie; Caspi, AvshalomRATIONALE: Asthma is prospectively associated with age-related chronic diseases and mortality, suggesting the hypothesis that asthma may relate to a general, multisystem phenotype of accelerated aging. OBJECTIVES: To test whether chronic asthma is associated with a proposed biomarker of accelerated aging, leukocyte telomere length. METHODS: Asthma was ascertained prospectively in the Dunedin Multidisciplinary Health and Development Study cohort (n = 1,037) at nine in-person assessments spanning ages 9-38 years. Leukocyte telomere length was measured at ages 26 and 38 years. Asthma was classified as life-course-persistent, childhood-onset not meeting criteria for persistence, and adolescent/adult-onset. We tested associations between asthma and leukocyte telomere length using regression models. We tested for confounding of asthma-leukocyte telomere length associations using covariate adjustment. We tested serum C-reactive protein and white blood cell counts as potential mediators of asthma-leukocyte telomere length associations. MEASUREMENTS AND MAIN RESULTS: Study members with life-course-persistent asthma had shorter leukocyte telomere length as compared with sex- and age-matched peers with no reported asthma. In contrast, leukocyte telomere length in study members with childhood-onset and adolescent/adult-onset asthma was not different from leukocyte telomere length in peers with no reported asthma. Adjustment for life histories of obesity and smoking did not change results. Study members with life-course-persistent asthma had elevated blood eosinophil counts. Blood eosinophil count mediated 29% of the life-course-persistent asthma-leukocyte telomere length association. CONCLUSIONS: Life-course-persistent asthma is related to a proposed biomarker of accelerated aging, possibly via systemic eosinophilic inflammation. Life histories of asthma can inform studies of aging.Item Open Access Long-term dynamics of death rates of emphysema, asthma, and pneumonia and improving air quality.(Int J Chron Obstruct Pulmon Dis, 2014) Kravchenko, J; Akushevich, I; Abernathy, AP; Holman, S; Ross, WG; Lyerly, HKBACKGROUND: The respiratory tract is a major target of exposure to air pollutants, and respiratory diseases are associated with both short- and long-term exposures. We hypothesized that improved air quality in North Carolina was associated with reduced rates of death from respiratory diseases in local populations. MATERIALS AND METHODS: We analyzed the trends of emphysema, asthma, and pneumonia mortality and changes of the levels of ozone, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and particulate matters (PM2.5 and PM10) using monthly data measurements from air-monitoring stations in North Carolina in 1993-2010. The log-linear model was used to evaluate associations between air-pollutant levels and age-adjusted death rates (per 100,000 of population) calculated for 5-year age-groups and for standard 2000 North Carolina population. The studied associations were adjusted by age group-specific smoking prevalence and seasonal fluctuations of disease-specific respiratory deaths. RESULTS: Decline in emphysema deaths was associated with decreasing levels of SO2 and CO in the air, decline in asthma deaths-with lower SO2, CO, and PM10 levels, and decline in pneumonia deaths-with lower levels of SO2. Sensitivity analyses were performed to study potential effects of the change from International Classification of Diseases (ICD)-9 to ICD-10 codes, the effects of air pollutants on mortality during summer and winter, the impact of approach when only the underlying causes of deaths were used, and when mortality and air-quality data were analyzed on the county level. In each case, the results of sensitivity analyses demonstrated stability. The importance of analysis of pneumonia as an underlying cause of death was also highlighted. CONCLUSION: Significant associations were observed between decreasing death rates of emphysema, asthma, and pneumonia and decreases in levels of ambient air pollutants in North Carolina.