The effects of subchronic arsenate exposure on gene expression in the mouse lung
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Russell Thomas
PROVIDER: E-GEOD-21193 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Publications
Genome-wide analysis of DNA methylation and gene expression changes in the mouse lung following subchronic arsenate exposure.
Boellmann Frank F Zhang Lu L Clewell Harvey J HJ Schroth Gary P GP Kenyon Elaina M EM Andersen Melvin E ME Thomas Russell S RS
Toxicological sciences : an official journal of the Society of Toxicology 20100728 2
Alterations in DNA methylation have been proposed as a mechanism for the complex toxicological effects of arsenic. In this study, whole-genome DNA methylation and gene expression changes were evaluated in lungs from female mice exposed for 90 days to 50 ppm arsenate (As) in drinking water. DNA methylation changes were measured using reduced representation bisulfite deep sequencing. Differential methylation was observed in approximately 700 and 1900 start and transcribed regions, respectively. Th ...[more]
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2010-07-28 | E-GEOD-23179 | biostudies-arrayexpress
Project description:Hydrogen sulfide (H2S) is a naturally occurring gas that is also associated with several industries. The potential for widespread human inhalation exposure to this toxic gas is recognized as a public health concern. The nasal epithelium is particularly susceptible to H2S-induced pathology. Injury to and regeneration of the nasal respiratory mucosa occurred in animals with ongoing H2S exposure suggesting that the regenerated respiratory epithelium undergoes an adaptive response and becomes resistant to further H2S induced toxicity. To better understand this adaptive response, twenty-four naive 10-week old male Sprague-Dawley rats were exposed to air or 200 ppm H2S in a nose-only exposure system for 3h/d for 1 or 5 consecutive days. Nasal respiratory epithelial cells at the site of injury and regeneration were laser capture microdissected and gene expression profiles were generated at time 3h, 6h, 24h, and 144h post initial exposure using the Affymetrix Rat Genome 430 2.0 microarray. Gene ontology enrichment analysis identified early gene changes in such functional categories as signal transduction, inflammatory/defense response, cell cycle, and response to oxidative stress. Later gene changes occurred in categories involved in cell cycle, DNA repair, transport, and micro-tubule-based movement. These data contribute to our understanding of the nasal epithelial cells? response to inhaled environmental toxicants. A better understanding of the H2S cytotoxicity mechanism will improve human risk assessment. Experiment Overall Design: Twenty-four naive 10-week old male Sprague-Dawley rats were exposed to air or 200 ppm H2S in a nose-only exposure system for 3h/d for 1 or 5 consecutive days. Nasal respiratory epithelial cells at the site of injury and regeneration were laser capture microdissected and gene expression profiles were generated at time 3h, 6h, 24h, and 144h post initial exposure using the Affymetrix Rat Genome 430 2.0 microarray.
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