Dataset Information

Transcriptome profiling of the newborn mouse lung response to acute ozone exposure

ABSTRACT: Ozone is a major air pollutant in highly populated areas. High levels of ambient ozone have been associated with decreased lung function and increased exacerbations of asthma in children and adults. However, the effects of ozone on the newborn’s lung are largely unknown. This study was aimed at profiling the newborn lung response to ozone at the transcriptome level to define the impact of ozone pollutant on the developing postnatal lung. Newborn mice were exposed to ozone or filtered normal air for 3 h. Total RNA was isolated from lung tissues at 6 and 24 h after completion of exposure and was subjected to gene expression analysis using Whole Mouse Genome Gene Expression 4X44K Microarrays (G2519F-014868, Agilent Technologies). Transcriptome analysis of the postnatal lung indicated that 455 genes were down-regulated and 166 genes were up-regulated by at least 1.5 fold at 6 h post-ozone exposure (t-test, p<0.05). At 24 h post exposure, 543 genes were down-regulated and 323 genes were up-regulated in the lungs of ozone-exposed newborn mice, compared to filtered air-exposed newborn mice (t-test, p<0.05). After controlling for false discovery rate, 50 genes were significantly down-regulated and only 4 genes were up-regulated at 24 h post ozone-exposure (q<0.05). Gene ontology enrichment analysis revealed that cell cycle-associated functions including cell division/proliferation, cellular assembly and organization were the predominant pathways negatively regulated by ozone exposure. These findings suggest that elevated ozone pollution may interfere with lung development and growth in the early age.

ORGANISM(S): Mus musculus

PROVIDER: GSE45166 | GEO | 2014/03/12

SECONDARY ACCESSION(S): PRJNA193099

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Ozone is a major air pollutant in highly populated areas. High levels of ambient ozone have been associated with decreased lung function and increased exacerbations of asthma in children and adults. However, the effects of ozone on the newbornM-bM-^@M-^Ys lung are largely unknown. This study was aimed at profiling the newborn lung response to ozone at the transcriptome level to define the impact of ozone pollutant on the developing postnatal lung. Newborn mice were exposed to ozone or filtered normal air for 3 h. Total RNA was isolated from lung tissues at 6 and 24 h after completion of exposure and was subjected to gene expression analysis using Whole Mouse Genome Gene Expression 4X44K Microarrays (G2519F-014868, Agilent Technologies). Transcriptome analysis of the postnatal lung indicated that 455 genes were down-regulated and 166 genes were up-regulated by at least 1.5 fold at 6 h post-ozone exposure (t-test, p<0.05). At 24 h post exposure, 543 genes were down-regulated and 323 genes were up-regulated in the lungs of ozone-exposed newborn mice, compared to filtered air-exposed newborn mice (t-test, p<0.05). After controlling for false discovery rate, 50 genes were significantly down-regulated and only 4 genes were up-regulated at 24 h post ozone-exposure (q<0.05). Gene ontology enrichment analysis revealed that cell cycle-associated functions including cell division/proliferation, cellular assembly and organization were the predominant pathways negatively regulated by ozone exposure. These findings suggest that elevated ozone pollution may interfere with lung development and growth in the early age. Three-day old BALB/c mice were exposed for 3 h to ozone (1000 parts per billion). Age-matching littermate controls were exposed for 3 h to filtered normal air. Whole lung tissue was collected 6 and 24 h after completion of exposure to ozone or filtered air and was subjected to microarray analysis. Each time point was performed separately with its own filtered air littermate controls. Pups were cross-fostered during exposure so that all pups were with a dam during exposure. A total of 6-8 mice were initially included in each group and time point. Of these, n=4 mouse lungs were randomly selected for use in gene expression analysis.

Project description:Background: Ozone (O3) is the predominant oxidant air pollutant associated with respiratory inflammation, lung dysfunction, and worsening preexisting airway diseases. We determined that TNFR signlaing pathway plays a key role in lung injury and inflammation caused by O3 in mice. However, downstream molecular mechanisms underlying TNFR pathway have not been investigated. Methods: To investigate the role of TNFR pathway in gene expression changes, Tnfr1/2-deficient (Tnfr-/-) and wild-type (Tnfr+/+, C57BL/6J) mice were exposed to air or 0.3-ppm O3. Total RNAs were isolated from lung homogenates and cDNA microarray analyses were performed to elucidate TNFR-directed transcriptomics in basal lungs (air-exposed) as well as in the lung exposed to time course of O3 (24, 48, and 72 hr). Results: O3 caused time-dependent changes in lung gene expressions with the greatest transcriptome changes at 48-72 hr of exposure in Tnfr+/+ mice. At early time of exposure (24 hr), acute phase and inflammatory responses gene as well as redox and lipid metabolism genes were increased by O3 while cell cycle and DNA damage repair genes were markedly increased by O3 at later time points (48-72 hr). Compared to Tnfr+/+ mice, Tnfr-/- mice had lowered expression of inflammatory response and vascular disorder-related genes at baseline (air). After O3 exposure, Tnfr-/- had enhanced expression of immune and inflammatory genes at 24 hr, indicating compensatory or adpative poentiation of immunity in Tnfr-/- mice. At 48 hr of O3 exposure, Tnfr-/- mice showed suppressed expression of genes involved in epithelial proliferation, inflammatory cell influxes and epithelial injury, compared to Tnfr+/+ mice. At 72 hr of O3 exposure, neurodegeneration and neurotransmitter transport genes were suppressed in Tnfr-/- than in Tnfr+/+. Conclusion: Overall, deficiency of TNFR-mediated signaling in mouse lungs altered transcriptomes to protect lungs from O3-induced inflammation, cell proliferation, oxidative stress, and neuronal disorders.

Project description:Rationale: Previous work demonstrated that pre-exposure to ozone primes innate immunity and increases TLR4-mediated response to subsequent stimulation with lipopolysaccharide (LPS). To further explore the pulmonary innate immune response to ozone exposure, we investigated the effect of ozone in combination with Pam3CYS, a synthetic TLR2/TLR1 agonist. Methods: Bronchoalveolar lavage (BAL) and lungs were harvested from C57Bl/6 mice after exposure to ozone or filtered air followed by saline or Pam3CYS 24 hours later. Cells and cytokines in the BAL, surface expression of TLRs on macrophages, and lung RNA genomic expression profiles were examined. Results: We demonstrate an increased BAL cell influx, increased IL-6 and KC, and decreased MIP-1α and TNF-α in response to Pam3CYS as a result of ozone pre-exposure. We also observed increased cell surface expression of TLR4, TLR2 and TLR1 on macrophages as a result of ozone alone or in combination with Pam3CYS. Gene expression analysis of lung tissue revealed a significant increase in expression of genes related to injury repair and cell cycle as a result of ozone exposure. When comparing Pam3CYS treated animals to saline treated animals with or without ozone, genes associated with inflammation were significantly increased. Potentially novel ozone exposure candidate genes (CCK, RELM-α and β) were identified. Conclusion: Our results extend previous findings with ozone/LPS to other TLRs PAMPs and suggest that ozone priming of innate immunity is a general mechanism. Gene expression profiling of lung tissue identified transcriptional networks and genes that contribute to the priming of innate immunity at the molecular level. Mice were exposed to either 2ppm ozone or filtered air (FA) for 3 hours. 24 hours following ozone exposure, mice from either the ozone or FA group were treated intratracheally with either 100ug of Pam3CYS in saline or saline alone. Animals were euthanized 4 or 24 hours post-Pam3CYS exposure. RNA from whole lung tissue from 4 animals per group was profiled.

Dataset Information

Transcriptome profiling of the newborn mouse lung response to acute ozone exposure

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure