Asthma is the most common chronic disease among children and current management focuses on control using medications and avoidance of factors that exacerbate the disease. Exposure to outdoor and indoor air pollutants, including nitrogen dioxide (NO2), which is a byproduct of combustion, has been associated with worsening asthma morbidity. Recent evidence suggests that hourly peak concentrations of ambient NO2 are associated with increases in emergency department visits and hospitalizations in people with asthma, prompting the EPA to modify the NAAQS standard for ambient NO2 to include an hourly concentration limit of 100ppb. Investigations by members of this research group have shown an association between higher mean concentrations of indoor NO2 and worsening respiratory symptoms in Baltimore children with asthma. Combustion sources, such as gas stoves, are unique to the indoor environment and produce short-term peak concentrations of NO2 that are not captured in mean concentrations measured over several days. However, the effect of peak indoor NO2 concentrations on asthma health is unknown. We hypothesize that these peak concentrations contribute to worse asthma and are more strongly linked to respiratory health than daily or weekly averages of NO2 concentrations. To study the effect of short-term and peak NO2 concentrations on asthma symptoms and lung function in children with asthma, we propose to add continuous monitoring of indoor NO2 concentrations and the administration of comprehensive time activity diaries in a subgroup (n=40) of children with asthma already enrolled in an existing study, The Center for Childhood Asthma in the Urban Environment ASTHMA-DIET Study. This proposal has three novel aims. First, to determine whether daily peak indoor NO2 concentrations are associated with asthma morbidity in inner city children, we will examine the effect of daily peak indoor NO2 concentrations on lung function and symptoms in children with asthma. Second, to determine whether daily average indoor NO2 concentrations are associated with asthma morbidity in inner city children, we will examine the relationship between 24-hour average NO2 concentrations and asthma outcomes. Finally, we will use detailed time activity diaries to determine the relative contribution of indoor sources to short-term variability in NO2 concentrations in inner-city homes. Results from this study will identify potential sources of elevated NO2 concentrations and inform whether future intervention studies can be directed at short-term increases in NO2 concentrations, which may be more cost-effective and feasible than strategies aimed at continuous NO2 reduction.

Dr. Diette is Associate Professor of Medicine at the Johns Hopkins University School of Medicine, where he has joint appointments in Epidemiology and Environmental Health Sciences at the Bloomberg School of Public Health. Since joining the faculty, Dr. Diette has served as mentor to more than 20 trainees, including 14 postdoctoral fellows. With rare exception, his mentees have gone on to highly productive academic careers, garnering honors and receiving NIH grant support (NRSA, K23, R21, R01 U01 and Project Leader on program grants). The majority of his professional life has been dedicated to the conduct of research, presentation and dissemination of findings and establishing a steady base of research funding from the NIH and other sources. The focus of Dr. Diette's career has been on patient-oriented research in asthma, especially race-based health care disparities and environmental determinants of the disease. The main purpose of this K24 proposal is to provide relief from clinical and administrative duties in order to expand the POR program and dedicate additional time and energy to current and future trainees. Thus, the overall aims of this proposal are: Aim 1: To enhance the candidate's capacity to mentor clinician scientists in patient-oriented research; and Aim 2: To expand the candidate's clinical research program in directions that create new scientific opportunities for him and his mentees. Dr. Diette directs the ASTHMA-DIET, a program award examining how diet contributes to asthma susceptibility in children and co-directs the Hopkins DISCOVER program, which investigates mechanisms by which allergens and pollutants provoke inflammation and oxidative stress. These programs are the research homes for his current mentees. These multi-project programs bring together broad scientific expertise from allergists, pulmonologists, adult and pediatric medicine, biostatisticians, epidemiologists, environmental health engineers and others. While substantial evidence now exists for the role of the indoor environment in pediatric asthma, there is insufficient evidence of the biologic mechanisms by which allergens and pollutants may provoke inflammation and oxidative stress in inner city adults. As adults with asthma endure the majority (90%) of mortality attributed to the disease, treatments are inadequate, especially in the area of environmental control. A major focus of this proposal will be to expand the present research program from inner city children to also include inner city adults. The proposed cohort of 100 inner city adults with asthma will examine the extent to which indoor particulate matter provokes oxidative stress and inflammation. With this expansion in the research program, the candidate will provide the foundation for future trials in adults of home-based multi- component environmental interventions, goals which are concordant with the career goals of current mentees and will establish the infrastructure for future mentees with a research interest in adult asthma.

Dr. Murugappan Ramanathan is a junior faculty member in the Department of Otolaryngology-Head & Neck Surgery at the Johns Hopkins School of Medicine where his clinical practice is dedicated to the medical and surgical management of nasal and sinus disorders. His previous research focused on impaired sinonasal epithelial innate immune responses in patients with chronic sinusitis. With the support of this Mentored Career Development Award, Dr. Ramanathan seeks to better understand the impact of indoor environmental exposure (particulate matter and allergens) on oxidative stress based sinonasal inflammation regulated by the Nrf2 anti- oxidant pathway. Dr. Ramanathan will enhance his research knowledge and skills with coursework in environmental health and air pollution, receive directed mentorship by an interdisciplinary team of experienced researchers, and be immersed in the interdisciplinary research and clinical environments of the Johns Hopkins School of Medicine, Johns Hopkins Bloomberg School of Public Health, and the Center for Childhood Asthma in the Urban Environment. This Career Development Award will provide Dr. Ramanathan with the resources that he needs to become an independent investigator and future leader in environmental exposure related sinonasal inflammation research. Building on his prior research experience in chronic sinonasal inflammation, Dr. Ramanathan has now transitioned his focus towards examining how the indoor environmental pollutants and allergens propagate oxidative stress related sinonasal inflammation. He is also interested in how the novel drug targetable transcription factor, Nrf2, may control the mucosal inflammatory state. In Aim 1a, he will determine the role of Nrf2 in regulating indoor particulate matter (PM) induced sinonasal inflammation in an allergic rhinitis mouse model. Aim 1b will use sinonasal epithelial cells grown in culture from control and chronic sinusitis patients and expose them in vitro to indoor PM or environmental mouse allergen. Subsequently, levels of inflammation, oxidative stress, and Nrf2 dependent antioxidants will be measured. In Aim 1c, Dr. Ramanathan will use asthmatic patients from the existing NIEHS ASTHMA-DIET study and correlate sinonasal levels of inflammation, oxidative stress, and levels of Nrf2 regulated antioxidants after intranasal mouse allergen challenge. Finally, in Aim 2, Dr. Ramanathan will use sulforaphane for chemoprotection to enhance levels of Nrf2 regulated antioxidants in both animal and cell culture models prior to environmental exposures. The process of performing these experiments will provide the candidate with the necessary guidance, coursework, and practical training towards becoming an independent investigator as well as furthering the basic science knowledge of sinonasal inflammation. Public Health Relevance: Chronic rhinosinusitis afflicts greater than 30 million individuals yearly and is among the most common conditions for which patients seek medical care in the US. While the pathogenesis of this disease is multi-factorial, very little research has examined the role of environmental exposure. This proposal will study the role of a critical pathway that may regulate environmentally induced inflammation in the nose and sinus and may ultimately lead to more effective therapies for chronic sinusitis.

Second-hand tobacco-smoke (SHS) has a profoundly negative impact on the health of exposed individuals. In adults, where the long-term impacts of SHS exposure are more apparent, SHS is responsible for 50,000 deaths annually. In children, the effects of SHS are likely even more profound. Children exposed to SHS have median nicotine metabolite levels twice those of adults, and SHS exposure is a substantial source of childhood morbidity; resulting in lower respiratory illnesses; cough, phlegm, wheeze, and breathlessness; middle ear disease; and a lower level of lung function. A critical need in the area of research into the health consequences of SHS is the development of effective tools for assessing the early biological response to SHS. These tools could facilitate rapid insights into the causes and consequences of differences in the response to SHS exposure; and, unlike direct measures of SHS exposure levels, could also be used to assess the likely long-term health effects of interventions to minimize SHS exposure in both children and adults. Using genome-wide microarray technologies for assessing mRNA and miRNA expression together with the concept that tobacco smoke creates an airway-wide field of epithelial cell injury, we have developed innovative genomic biomarkers to assess the biologic response to SHS by profiling cells that can be collected from the mouth or nose using minimally invasive procedures. These biomarkers combine the expression levels of multiple genes or miRNAs into composite measures of tobacco-smoke exposure thereby amplifying the tobacco-smoke signal while dampening the otherwise noisy expression levels of individual genes. Preliminary studies show that expression biomarkers measured in buccal or nasal epithelium distinguish young adults with SHS exposure from unexposed individuals. The studies proposed here will validate these biomarkers for assessing the biological response to SHS in 80 SHS-exposed and 80 unexposed children participating in the CCCEH, DISCOVER and ASTHMA-DIET cohorts. Biomarkers of tobacco-smoke exposure derived from microarray-based measurements of nasal or buccal epithelial mRNA or miRNA expression will be compared to measures of SHS exposure derived from questionnaire, air sampling and cotinine. The repeatability of the genomic biomarker measurements will be assessed by repeat sampling of 40 children after 6 months. The proposed research applies innovative tools for measuring the biological response to SHS exposure to multiple established cohorts with carefully characterized exposures, including children at risk for SHS-related disease. The studies bring together a team with expertise in pulmonary medicine, epidemiology, genomics, and biostatistics, a long-term interest in understanding responses to tobacco smoke, and an established record of effective collaboration, to take a critical step in establishing the potential and feasibility of applying these SHS-exposure assessment tools to large-scale epidemiology and gene-environment studies. By measuring the response to exposure, rather than the exposure itself, these studies have the potential to broadly change the paradigm for research into the effects of environmental exposures.

Asthma is a common and complex disorder. In the U.S., the burden of asthma is enormous, with a disproportionate impact on vulnerable groups including young children, African-Americans and those living in the inner city. These most vulnerable people often inhabit an environment that has excessive pollution levels, including high levels of indoor pollutants and allergens. Furthermore, the diet of low-income, inner city African-Americans is markedly inconsistent with national nutritional guidelines, and has a pattern that may leave them especially vulnerable to the effects of inhaled pollutants and allergens. To address the critical questions of the role of dietary intake and the indoor environment on childhood asthma, we propose a panel study of children living in urban neighborhoods enriched with African-American and lower income participants. We have already shown that in the neighborhoods of the proposed study participants that in-home pollutant levels, including particulate matter (PM) and nitrogen dioxide (NO2), greatly exceed the outdoor levels and suburban indoor levels and that these in-home pollutants are independently associated with increased asthma morbidity. Furthermore, we have already demonstrated that the diet in this high-risk population is poor and is of a pattern that is inconsistent with dietary patterns that have been shown to protect against asthma. We plan to examine the effect of the poor "inner city" diet on susceptibility of asthmatic children to in-home pollutant (PM and NO2) exposure (Aim 1), and to identify barriers and enabling factors to implementing dietary and environmental modifications in inner city homes of children with asthma (Aim 2). To address these aims will plan to recruit 200 children with asthma, ages 5-12, in inner city Baltimore, each of whom will undergo 3 seven-day monitoring periods (at baseline, 3 months and 6 months) where they will undergo indoor air monitoring, dietary and respiratory assessments, nasal lavage, exhaled nitric oxide measurements, urine collection and blood draw for markers of inflammation and oxidative stress. Importantly, the aims in this application build upon the well-established infrastructure of a group of experienced investigators with diverse but highly integrated areas of expertise. This real-world field-based study will complement the findings from Projects 2 and 3 by demonstrating the clinical effect of diet on response to indoor pollutants, and by providing corroborative evidence of the oxidative stress and inflammatory pathways by which they may act. Projects 2 and 3 will similarly examine the effects of diet on response to pollutants, but in controlled settings using human subjects and animal.

Asthma is a common disorder among children. Children with asthma have multiple and complex environmental exposures, including inhalable pollutants and allergens. The response to inhaled exposures is characterized by airway inflammation, and possibly by activation of oxidative stress pathways. In the U.S., the burden of asthma is enormous, with a disproportionate impact on vulnerable groups including young children, African-Americans and those living in the inner city. These most vulnerable people often inhabit an environment that has excessive outdoor pollution levels, as well as high levels of indoor allergens and pollutants. We plan to address the critical questions of the role of the indoor environment on childhood asthma, we propose a panel study of children living in urban neighborhoods enriched with African-American and lower income participants. This real world field-based study will complement the findings from Projects 2, 3 and 4, which will similarly examine the effects of PM and allergen, but in controlled settings using human subjects, animal models and cell systems. We will recruit atopic asthmatics, including those with and without sensitization to mouse allergen, as well as normal controls, to address the following Specific Aims: Aim 1 .A: To determine the contribution of indoor PM to day-to-day variation in lung function and asthma control, among inner city children with atopic asthma. Aim IB: To determine if higher indoor PM exposure is associated with biomarkers of inflammation and oxidative stress. Aim 2A: To determine if mouse IgE-positive asthmatics with high mouse allergen exposure have greater susceptibility to PM than other atopic asthmatics (mouse IgE-negative and/or with low mouse allergen exposure). Aim 2.B: To determine if mouse IgE-positive asthmatics with high mouse allergen exposure (> 0.5 ug/g of Mus m 1) have elevated biomarkers of inflammation and oxidative stress in response to PM compared to those who are mouse IgE-E negative or who have low mouse allergen exposure.