title: DIESEL particulate exposed macrophages alter endothelial cell expression of eNOS, iNOS, MCP1, and glutathione synthesis genes.
abstract: There is considerable debate regarding inhaled diesel exhaust particulate (DEP) causing impairments in vascular reactivity. Although there is evidence that inhaled particles can translocate from the lung into the systemic circulation, it has been suggested that inflammatory factors produced in the lung following macrophage particle engulfment also pass into the circulation. To investigate these differing hypotheses, we used in vitro systems to model each exposure. By using a direct exposure system and a macrophage-endothelial cell co-culture model, we compared the effects of direct DEP exposure and exposure to inflammatory factors produced by DEP-treated macrophages, on endothelial cell mRNA levels for eNOS, iNOS, endothelin-1, and endothelin-converting-enzyme-1. As markers of oxidative stress, we measured the effects of DEP treatment on glutathione (GSH) synthesis genes and on total GSH. In addition, we analyzed the effect of DEP treatment on monocyte chemo-attractant protein-1. Direct DEP exposure increased endothelial GCLC and GCLM as well as total GSH in addition to increased eNOS, iNOS, and Mcp1 mRNA. Alternatively, inflammatory factors released from DEP-exposed macrophages markedly up-regulated endothelial iNOS and Mcp1 while modestly down-regulating eNOS. These data support both direct exposure to DEP and the release of inflammatory cytokines as explanations for DEP-induced impairments in vascular reactivity.
authors.affiliation: Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, United States. weldyc@u.washington.edu
authors.forename: Chad S
authors.initials: CS
authors.lastname: Weldy
authors.forename: Hui-Wen
authors.initials: HW
authors.lastname: Wilkerson
authors.forename: Timothy V
authors.initials: TV
authors.lastname: Larson
authors.forename: James A
authors.initials: JA
authors.lastname: Stewart
authors.forename: Terrance J
authors.initials: TJ
authors.lastname: Kavanagh
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D002460:Cell Line; D018932:Chemokine CCL2 / Q000235:genetics; D018920:Coculture Techniques; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D005721:Glutamate-Cysteine Ligase / Q000235:genetics; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D052247:Nitric Oxide Synthase Type II / Q000235:genetics; D052250:Nitric Oxide Synthase Type III / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D000393:Air Pollutants; C491768:Ccl2 protein, mouse; D018932:Chemokine CCL2; D012333:RNA, Messenger; D001335:Vehicle Emissions; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496317:Nos2 protein, mouse; C496315:Nos3 protein, mouse; C560749:GCLM protein, mouse; D005721:Glutamate-Cysteine Ligase