Silicosis is an occupational lung disease resulting from the inhalation of silica particles which causes chronic inflammation and progressive pulmonary fibrosis. Phagocytosis of inhaled silica particles by alveolar macrophages (AM) and subsequent activation of AM is a crucial step in the pathogenesis of silicosis; however, the participation of specific intracellular signaling pathways in regulating this process remains largely unknown. The goal of this study is to test the central hypothesis that silica induced production of TNF alpha sustains inflammation by activating the Akt signaling pathway in AM.
The specific aims of this proposed research are: 1) to assess the cellular fate of AM following exposure to silica, 2) to determine the effects of silica on the Akt signaling pathways in AM, and 3) to elucidate the ability of silica induced TNF alpha production to stimulate the Akt signaling pathway and alter call fate (apoptosis vs. survival). Defining the function of this signaling pathway in regulating AM activation and cell fate is of interest because a better understanding of the molecular events involved may permit targeting of key biochemical pathways for more effective diagnosis and treatment of occupational lung diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32ES013044-03
Application #
7091620
Study Section
Special Emphasis Panel (ZRG1-F10 (20))
Program Officer
Humble, Michael C
Project Start
2004-07-01
Project End
2007-06-30
Budget Start
2006-07-01
Budget End
2007-06-30
Support Year
3
Fiscal Year
2006
Total Cost
$52,048
Indirect Cost
Name
University of Montana
Department
Other Health Professions
Type
Schools of Pharmacy
DUNS #
010379790
City
Missoula
State
MT
Country
United States
Zip Code
59812
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Beamer, Celine A; Holian, Andrij (2005) Scavenger receptor class A type I/II (CD204) null mice fail to develop fibrosis following silica exposure. Am J Physiol Lung Cell Mol Physiol 289:L186-95