Detection of Dichlorvos Adducts
in a Hepatocyte Cell
Line
- Publication date
- Publisher
Abstract
The toxicity of dichlorvos (DDVP),
an organophosphate (OP) pesticide,
classically results from modification of the serine in the active
sites of cholinesterases. However, DDVP also forms adducts on unrelated
targets such as transferrin and albumin, suggesting that DDVP could
cause perturbations in cellular processes by modifying noncholinesterase
targets. Here we identify novel DDVP-modified targets in lysed human
hepatocyte-like cells (HepaRG) using a direct liquid chromatography–mass
spectrometry (LC–MS) assay of cell lysates incubated with DDVP
or using a competitive pull-down experiments with a biotin-linked
organophosphorus compound (10-fluoroethoxyphosphinyl-<i>N</i>-biotinamidopentyldecanamide; FP-biotin), which competes with DDVP
for similar binding sites. We show that DDVP forms adducts to several
proteins important for the cellular metabolic pathways and differentiation,
including glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and actin.
We validated the results using purified proteins and enzymatic assays.
The study not only identified novel DDVP-modified targets but also
suggested that the modification directly inhibits the enzymes. The
current approach provides information for future hypothesis-based
studies to understand the underlying mechanism of toxicity of DDVP
in non-neuronal tissues. The MS data have been deposited to the ProteomeXchange
with identifier PXD001107