Coal dust alters β-naphthoflavone-induced aryl hydrocarbon receptor nuclear translocation in alveolar type II cells

Authors

Mohamed M. Ghanem, West Virginia University
Lori A. Battelli, West Virginia University
Brandon F. Law, National Institute for Occupational Safety and Health
Vincent Castranova, National Institute for Occupational Safety and Health
Michael L. Kashon, National Institute for Occupational Safety and Health
Joginder Nath, West Virginia University
Ann F. Hubbs, West Virginia University

Author ORCID Identifier

https://orcid.org/0000-0001-6769-7875

N/A

https://orcid.org/0000-0002-3658-6547

N/A

N/A

N/A

https://orcid.org/0000-0001-8631-5123

Document Type

Article

Publication Date

2009

College/Unit

Eberly College of Arts and Sciences

Department/Program/Center

Biology

Abstract

Background

Many polycyclic aromatic hydrocarbons (PAHs) can cause DNA adducts and initiate carcinogenesis. Mixed exposures to coal dust (CD) and PAHs are common in occupational settings. In the CD and PAH-exposed lung, CD increases apoptosis and causes alveolar type II (AT-II) cell hyperplasia but reduces CYP1A1 induction. Inflammation, but not apoptosis, appears etiologically associated with reduced CYP1A1 induction in this mixed exposure model. Many AT-II cells in the CD-exposed lungs have no detectable CYP1A1 induction after PAH exposure. Although AT-II cells are a small subfraction of lung cells, they are believed to be a potential progenitor cell for some lung cancers. Because CYP1A1 is induced via ligand-mediated nuclear translocation of the aryl hydrocarbon receptor (AhR), we investigated the effect of CD on PAH-induced nuclear translocation of AhR in AT-II cells isolated from in vivo-exposed rats. Rats received CD or vehicle (saline) by intratracheal (IT) instillation. Three days before sacrifice, half of the rats in each group started daily intraperitoneal injections of the PAH, β-naphthoflavone (BNF).

Results

Fourteen days after IT CD exposure and 1 day after the last intraperitoneal BNF injection, AhR immunofluorescence indicated that proportional AhR nuclear expression and the percentage of cells with nuclear AhR were significantly increased in rats receiving IT saline and BNF injections compared to vehicle controls. However, in CD-exposed rats, BNF did not significantly alter the nuclear localization or cytosolic expression of AhR compared to rats receiving CD and oil.

Conclusion

Our findings suggest that during particle and PAH mixed exposures, CD alters the BNF-induced nuclear translocation of AhR in AT-II cells. This provides an explanation for the modification of CYP1A1 induction in these cells. Thus, this study suggests that mechanisms for reduced PAH-induced CYP1A1 activity in the CD exposed lung include not only the effects of inflammation on the lung as a whole, but also reduced PAH-associated nuclear translocation of AhR in an expanded population of AT-II cells.

Digital Commons Citation

Ghanem, Mohamed M.; Battelli, Lori A.; Law, Brandon F.; Castranova, Vincent; Kashon, Michael L.; Nath, Joginder; and Hubbs, Ann F., "Coal dust alters β-naphthoflavone-induced aryl hydrocarbon receptor nuclear translocation in alveolar type II cells" (2009). Faculty & Staff Scholarship. 2828.
https://researchrepository.wvu.edu/faculty_publications/2828

Source Citation

Ghanem, M.M., Battelli, L.A., Law, B.F. et al. Coal dust alters β-naphthoflavone-induced aryl hydrocarbon receptor nuclear translocation in alveolar type II cells. Part Fibre Toxicol 6, 21 (2009). https://doi.org/10.1186/1743-8977-6-21

Comments

© 2009 Ghanem et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.