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Published on: December 27, 2016
Heptachlor and the mitogen-activated protein kinase module in human lymphocytes
1Department of Medical Pharmacology and Toxicology, School of Medicine, University of California, Davis 95616, USA.
Toxicology
|August 15, 1998
Summary
The organochlorine pesticide heptachlor affects immune cell signaling by altering mitogen-activated protein kinase (MAPK) pathways. Heptachlor exposure increases activated MAPK levels, suggesting a negative feedback mechanism in immune cells.
Area of Science:
- Environmental Toxicology
- Immunology
- Molecular Biology
Background:
- Organochlorine pesticides like heptachlor pose health risks due to persistence and potential carcinogenicity.
- Heptachlor acts as a tumor promoter, inducing differentiation in leukemia cells and down-regulating the p53 tumor suppressor gene.
Purpose of the Study:
- To investigate the heptachlor signaling pathway in human lymphocytes.
- To understand the role of mitogen-activated protein kinases (MAPKs) in immune cell response to heptachlor.
Main Methods:
- Human CEM x174 lymphocytic cells were treated with heptachlor.
- Levels of MAPK cascade proteins, including ERK1, ERK2, MEK1, and MEKK, were analyzed.
- Expression of activated (phosphorylated) ERK1 and ERK2 was measured.
Main Results:
- Heptachlor reduced cellular levels of basal MAPK cascade proteins.
- A significant increase in activated ERK1 and ERK2 was observed following heptachlor treatment.
- The results indicate MAPK activation without basal enzyme accumulation.
Conclusions:
- Mitogen-activated protein kinases are key intermediates in immune cell signal transduction upon heptachlor exposure.
- The observed MAPK activation suggests a potential negative feedback mechanism in the immune response pathway.
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