You are here:
THE DEVELOPMENT OF AN IN VITRO ASSAY FOR EVALUATING THE BINDING OF PERFLUOROALKYL ACIDS (PFAAS) TO THE PEROXISOME PROLIFERATOR-ACTIVATED RECEPTORS (PPARS)
Citation:
TAKACS, M. AND B. D. ABBOTT. THE DEVELOPMENT OF AN IN VITRO ASSAY FOR EVALUATING THE BINDING OF PERFLUOROALKYL ACIDS (PFAAS) TO THE PEROXISOME PROLIFERATOR-ACTIVATED RECEPTORS (PPARS). Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Description:
The purpose of this work was to evaluate the binding of PFAAs to PPAR receptors and determine the potential for activation or antagonism of the pathway during embryonic development. Activation of mouse and human PPAR isoforms by perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) was investigated using a transient transfection cell assay. Cos-1 cells were cultured in DMEM with fetal bovine serum (FBS) and transfected with mouse or human PPAR? Luciferase reporter plasmids in 96-well plates. To evaluate PPAR? activation, cells were exposed to freshly prepared solutions of PFOA (0.5- 40 ?M), PFOS (1-250 ?M), the PPAR? agonist (WY14643 [10 ?M]), or antagonist (MK866 [20 ?M]), positive (agonist and antagonist), and negative control (DMEM, water, and 0.1% DMSO). Activity was measured using the Luciferase reporter assay following treatment for 24 hours. PFOA maximally activated mouse PPAR? at 40 ?M with a 1-2 fold inhibition when challenged with MK866. Human PPAR? had maximal activity at 30-40 ?M PFOA with a 2-3 fold inhibition by MK866. PFOS maximally activated mouse and human PPAR? at 120 ?M with a 1-2 fold inhibition for mouse PPAR? and a 1-3 fold inhibition for human PPAR? by MK866. The suppression of activity by the antagonist was not significant in the mouse PPAR ? construct exposed to PFOA or PFOS. However, in the human PPAR ? construct there was a significant difference in suppression at 3, 10, 15, 20, 30, and 40 ?M for PFOA (P<0.05) and 10, 60, 90, and 120 ?M for PFOS (P<0.05). In conclusion, this study has characterized the dose response and differences between mouse and human PPAR? activation by PFOA and PFOS. On-going work will use this model to evaluate other PFAAs and extend the method to mouse and human PPAR? and ?. This abstract does not necessarily reflect U.S. EPA policy.