Age specific responses to acute inhalation of diffusion flame soot particles: Cellular injury and the airway antioxidant response
Authors: Van Winkle, Laura S.; Chan, Jackie K.W.1; Anderson, Donald S.1; Kumfer, Benjamin M.; Kennedy, Ian M.2; Wexler, Anthony S.3; Wallis, Christopher3; Abid, Aamir D.2; Sutherland, Katherine M.1; Fanucchi, Michelle V.4
Source: Inhalation Toxicology, Volume 22, Supplement 2 to issue 1, December 2010 , pp. 70-83(14)
Publisher: Informa Healthcare
Abstract:Current studies of particulate matter (PM) are confounded by the fact that PM is a complex mixture of primary (crustal material, soot, metals) and secondary (nitrates, sulfates, and organics formed in the atmosphere) compounds with considerable variance in composition by sources and location. We have developed a laboratory-based PM that is replicable, does not contain dust or metals and that can be used to study specific health effects of PM composition in animal models. We exposed both neonatal (7 days of age) and adult rats to a single 6-h exposure of laboratory generated fine diffusion flame particles (DFP; 170 µg/m3), or filtered air. Pulmonary gene and protein expression as well as indicators of cytotoxicity were evaluated 24 h after exposure. Although DFP exposure did not alter airway epithelial cell composition in either neonates or adults, increased lactate dehydrogenase activity was found in the bronchoalveolar lavage fluid of neonates indicating an age-specific increase in susceptibility. In adults, 16 genes were differentially expressed as a result of DFP exposure whereas only 6 genes were altered in the airways of neonates. Glutamate cytsteine ligase protein was increased in abundance in both DFP exposed neonates and adults indicating an initiation of antioxidant responses involving the synthesis of glutathione. DFP significantly decreased catalase gene expression in adult airways, although catalase protein expression was increased by DFP in both neonates and adults. We conclude that key airway antioxidant enzymes undergo changes in expression in response to a moderate PM exposure that does not cause frank epithelial injury and that neonates have a different response pattern than adults.
Document Type: Research Article
Affiliations: 1: 2Center for Health and the Environment, University of California Davis, Davis, California, USA 2: 4Department of Mechanical and Aerospace Engineering, University of California Davis, Davis, California, USA 3: 3Air Quality Research Center, University of California Davis, Davis, California, USA 4: 6Department of Environmental Health Sciences, School of Public Health, University of Alabama, Birmingham, Alabama, USA
Publication date: December 1, 2010
- In this: publication
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- In this Subject: Internal Medicine
- By this author: Van Winkle, Laura S. ; Chan, Jackie K.W. ; Anderson, Donald S. ; Kumfer, Benjamin M. ; Kennedy, Ian M. ; Wexler, Anthony S. ; Wallis, Christopher ; Abid, Aamir D. ; Sutherland, Katherine M. ; Fanucchi, Michelle V.