Organic compounds from diesel exhaust particles elicit a proinflammatory response in human airway epithelial cells and induce cytochrome p450 1A1 expression.
Diesel exhaust particles (DEP) are known to enhance inflammatory responses in human volunteers. In cultured human bronchial epithelial (16HBE) cells, they induce the release of proinflammatory cytokines after triggering transduction pathways, including nuclear factor (NF)-kappaB activation and mitogen-activated protein kinase (MAPK) phosphorylation. This study compares the effects of native DEP (nDEP), organic extracts of DEP (OE-DEP), and carbonaceous particles, represented by stripped DEP (sDEP) and carbon black particles (CB), in order to clarify their respective roles. OE-DEP and nDEP induce granulocyte macrophage colony-stimulating factor (GM-CSF) release, NF-kappaB activation, and MAPK phosphorylation. The carbonaceous core generally induces less intense effects. Reactive oxygen species are produced in 16HBE cells and are involved in GM-CSF release and in the stimulation of NF-kappaB DNA binding by nDEP and OE-DEP. We demonstrate, for the first time, in airway epithelial cells in vitro that nDEP induce the expression of the CYP1A1, a cytochrome P450 specifically involved in polycyclic aromatic hydrocarbons metabolism, thereby demonstrating the critical role of organic compounds in the DEP-induced proinflammatory response. Understanding the respective contributions of DEP components in these effects is important for vehicle manufacturers in order to improve their exhaust gas post-treatment technologies. In conclusion, the DEP-induced inflammatory response in airway epithelial cells mainly involves organic compounds such as PAH, which induce CYP1A1 gene expression.
Bonvallot
V
V
Laboratoire de Cytophysiologie et Toxicologie Cellulaire, Université Paris VII Denis Diderot, 2, place Jussieu, 75251 Paris cedex 05, France. bonvallot@paris7.jussieu.fr
Baeza-Squiban
A
A
Baulig
A
A
Brulant
S
S
Boland
S
S
Muzeau
F
F
Barouki
R
R
Marano
F
F
D002478:Cells, Cultured; D019363:Cytochrome P-450 CYP1A1 / Q000187:drug effects / Q000235:genetics*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism; D016328:NF-kappa B / Q000187:drug effects / Q000378:metabolism; D009930:Organic Chemicals / Q000009:adverse effects / Q000737:chemistry; D010766:Phosphorylation; D017382:Reactive Oxygen Species / Q000378:metabolism; D020545:Respiratory Mucosa / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D001335:Vehicle Emissions / Q000009:adverse effects*
D016328:NF-kappa B; D009930:Organic Chemicals; D017382:Reactive Oxygen Species; D001335:Vehicle Emissions; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D019363:Cytochrome P-450 CYP1A1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases