Project description:To investigate the biochemical and genetic alterations that occur in response to cigarette smoke exposure among airway epithelial cells from different sites in the lungs, we performed microarray-based analysis using small airway epithelial cells (SAEC) and normal human bronchial epithelial cells (NHBE) following 24 h of cigarette smoke extract (CSE). In microarray-based analysis, the small airway showed higher susceptibility to CS compared to the large airway, such as enhanced expression of inflammatory-related pathways including the TNF signaling pathway. Among the TNF-related genes, PTGS2, also known as COX-2, showed the greatest difference in expression levels, with higher CSE-induced increments of both mRNA and protein expression in SAEC compared to NHBE.
Project description:Introduction: Prenatal and postnatal cigarette smoke exposure enhances the risk of developing asthma. Despite this as well as other smoking related risks, 11% of women still smoke during pregnancy. We hypothesized that cigarette smoke exposure during prenatal development generates long lasting differential methylation altering transcriptional activity that correlates with disease. Methods: In a house dust mite (HDM) model of allergic airway disease, we measured airway hyperresponsiveness (AHR) and airway inflammation between mice exposed prenatally to cigarette smoke (CS) or filtered air (FA). DNA methylation and gene expression were then measured in lung tissue. Results: We demonstrate that HDM-treated CS mice develop a more severe allergic airway disease compared to HDM-treated FA mice including increased AHR and airway inflammation. While DNA methylation changes between the two HDM-treated groups failed to reach genome-wide significance, 99 DMRs had an uncorrected p-value < 0.001. 6 of these 99 DMRs were selected for validation, based on the immune function of adjacent genes, and only 2 of the 6 DMRs confirmed the bisulfite sequencing data. Additionally, genes near these 6 DMRs (Lif, Il27ra, Tle4, Ptk7, Nfatc2, and Runx3) are differentially expressed between HDM-treated CS mice and HDM-treated FA mice. Conclusions: Our findings confirm that prenatal exposure to cigarette smoke is sufficient to modify allergic airway disease, however, it is unlikely that specific methylation changes account for the exposure-response relationship. These findings highlight the important role in utero cigarette smoke exposure plays in the development of allergic airway disease.
Project description:Introduction: Prenatal and postnatal cigarette smoke exposure enhances the risk of developing asthma. Despite this as well as other smoking related risks, 11% of women still smoke during pregnancy. We hypothesized that cigarette smoke exposure during prenatal development generates long lasting differential methylation altering transcriptional activity that correlates with disease. Methods: In a house dust mite (HDM) model of allergic airway disease, we measured airway hyperresponsiveness (AHR) and airway inflammation between mice exposed prenatally to cigarette smoke (CS) or filtered air (FA). DNA methylation and gene expression were then measured in lung tissue. Results: We demonstrate that HDM-treated CS mice develop a more severe allergic airway disease compared to HDM-treated FA mice including increased AHR and airway inflammation. While DNA methylation changes between the two HDM-treated groups failed to reach genome-wide significance, 99 DMRs had an uncorrected p-value < 0.001. 6 of these 99 DMRs were selected for validation, based on the immune function of adjacent genes, and only 2 of the 6 DMRs confirmed the bisulfite sequencing data. Additionally, genes near these 6 DMRs (Lif, Il27ra, Tle4, Ptk7, Nfatc2, and Runx3) are differentially expressed between HDM-treated CS mice and HDM-treated FA mice. Conclusions: Our findings confirm that prenatal exposure to cigarette smoke is sufficient to modify allergic airway disease, however, it is unlikely that specific methylation changes account for the exposure-response relationship. These findings highlight the important role in utero cigarette smoke exposure plays in the development of allergic airway disease. Lung DNA methylation profiles of mice exposed in utero to cigarette smoke (CS) then treated with house dust mite (HDM, n = 8) or saline (n = 6), or exposed in utero to filtered air (FA) then treated with HDM (n = 9) or saline (n = 6)
Project description:Chronic obstructive pulmonary disease (COPD) is a disease state characterized by poorly reversible, limited airflow that is usually both progressive and associated with an abnormal inflammatory response of the lung. One cause of COPD is chronic exposure to airborne materials such as cigarette smoke (CS), which leads to impaired respiratory function in damaged tissues. Damaged epithelial tissue initiates repair processes including proliferation and re-differentiation until there is complete regeneration of a pseudostratified epithelium. These repair processes in airway epithelial tissues are essential for maintaining normal airway function. However, impairment of epithelial repair leads to architectural changes through region-dependent remodeling processes that are associated with a fixed airflow limitation in COPD. To fully understand what factors mostly contribute to airway remodeling heterogeneity in COPD pathogenesis, we used two in vitro human airway epithelial 3D culture models, namely, MucilAir™ and SmallAir™ tissues, which are derived from large and small airway epithelial cells, respectively. To focus on regional heterogeneity of the respiratory tract, tissues from a single donor were used to eliminate potential donor-to-donor differences in responses to external stimuli. We exposed the tissues to different concentrations of whole CS (low, middle, and high), and examined the transcriptome at different post-exposure periods (4, 24, 48, and 72 h post-exposure).
Project description:Although a number of animal model studies have addressed changes in gene expression in the parenchyma and their relationship to emphysema, much less is known about the pathogenesis of cigarette smoke-induced small airway remodeling. In this study, we exposed rat tracheal explants to whole smoke for 15 minutes, and then cultured the explants in air. The airway transcriptome was evaluated using RAE 230_2 GeneChips. By 2 hours after starting smoke exposure, expression levels of 502 genes were changed up or down by more than 1.5 times (p values <0.01 or less), and by 24 hours, 1870 genes were significantly changed up or down. These included genes involved in anti-oxidant protection, epithelial defense and remodeling, inflammatory mediators and transcription factors, and a number of unexpected genes including the MMP-12 inducer, tachykinin-1 (substance P). Pre-treatment of the explants with 1 x 10-7 M dexamethasone reduced the number of significantly changed genes by approximately 47% at 2 hr and 68% at 24 hours, and in almost all instances, reduced the magnitude of the smoke-induced changes. We conclude that even a very brief exposure to cigarette smoke can lead to rapid changes in the expression of a large number of genes in rat tracheal explants, and that these effects are directly mediated by smoke, without a need for exogenous inflammatory cells. Steroids, contrary to the usual belief, are able to ameliorate many of these changes, at least in this very acute model.
Project description:Although a number of animal model studies have addressed changes in gene expression in the parenchyma and their relationship to emphysema, much less is known about the pathogenesis of cigarette smoke-induced small airway remodeling. In this study we exposed rat tracheal explants to whole smoke for 15 minutes, and then cultured the explants in air. The airway transcriptome was evaluated using RAE 230_2 gene chips. By 2 hours after starting smoke exposure, expression levels of 502 genes were changed up or down by more than 1.5 times (p values <0.01 or less) and by 24 hours 1870 genes were significantly changed up or down. These included genes involved in anti-oxidant protection, epithelial defense and remodeling, inflammatory mediators and transcription factors, and a number of unexpected genes including the MMP-12 inducer, tachykinin-1 (substance P). Pre-treatment of the explants with 1 x 10-7 M dexamethasone reduced the number of significantly changed genes by approximately 47% at 2 hr and 68% at 24 hours and in almost all instances reduced the magnitude of the smoke-induced changes. We conclude that even a very brief exposure to cigarette smoke can lead to rapid changes in the expression of a large number of genes in rat tracheal explants, and that these effects are directly mediated by smoke, without a need for exogenous inflammatory cells. Steroids, contrary to the usual belief, are able to ameliorate many of these changes, at least in this very acute model. Experiment Overall Design: 4x tracheal explants (approx 2-3ug) from each rat (n=6 rats) exposed to control (air), smoke (10 puffs of cigarette smoke, delivered during 15 mins), dexamethasone and dexamethasone + cigarette smoke were used for RNA extraction and hybridization on Rat230_2 Affymetrix microarrays. 1 rat, 4 explants and 4 condiditons. n= 6 rats per group/condition 12 animals = 48 samples total (47 went into analysis because 1 sample failing QC metrics)
Project description:To study the effect of cigarette smoke exposure on Sars-Cov2 infection, we directly exposed mucociliary air-liquid interface (ALI) cultures derived from primary human nonsmoker airway basal stem cells (ABSCs) to short term cigarette smoke and infected them with live SARS-CoV-2. We set out to examine the underlying mechanisms governing the increased susceptibility of cigarette smoke exposed ALI cultures to SARS-CoV-2 infection by usingle cell profiling of the cultures, which showed that interferon response genes were induced in SARS-CoV-2 infected airway epithelial cells in ALI cultures but smoking exposure together with SARS-CoV-2 infection reduced the interferon response.
Project description:Airway epithelial cells are the first cells of the lungs to be exposed to the toxic agents contained within cigarette smoke. Accordingly, the response of these cells to this challenge is of considerable interest in the context of diseases in which cigarette smoke is a major aetiological factor. We used Affymetrix microarrays to study the effects of repeated cigarette smoke challenge on three-dimensional human lung airway epithelial cultures.
Project description:Our study discusses the importance of studying sex-specific differences in the response of the airway epithelium to chronic injury. It focuses on tracheal epithelial cells from male and female mice exposed to chronic cigarette smoke and found evidence of sex-specific differences in gene expression and epithelial plasticity. Understanding these differences could lead to more effective personalized treatments for respiratory diseases.