Premium
Detection of benzo(a)pyrene diol epoxide‐DNA adducts in mononuclear white blood cells by CE immunoassay and its application to studying the effect of glutathione depletion
Author(s) -
LeBlanc Adrienne,
Shen Shengwen,
Lew Kristi,
Weinfeld Michael,
Chris Le X.
Publication year - 2009
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200800391
Subject(s) - glutathione , chemistry , benzo(a)pyrene , adduct , carcinogen , dna , pyrene , microbiology and biotechnology , biochemistry , epoxide , immunoassay , buthionine sulfoximine , enzyme , immunology , biology , antibody , organic chemistry , catalysis
High levels of benzo(a)pyrene diol epoxide (BPDE)‐DNA adducts in white blood cells have been indicated as a risk factor for lung cancer. Sensitive, specific, fast and cost‐efficient techniques for the detection of BPDE‐DNA adducts in white blood cells are required for routine human biomonitoring. In the present study, an immunoassay based on CE/LIF was developed for the detection of BPDE‐DNA adducts in mononuclear white blood cells (MNCs). Although glutathione (GSH) conjugation catalyzed by glutathione‐ S ‐transferase (GST) is considered to be the major pathway for inactivating BPDE, the effect of GSH depletion on BPDE‐DNA adduct formation in MNCs has not been assessed. Therefore, we applied the newly developed method to study the effect of GSH depletion by d,l ‐buthionine‐[S,R]‐sulfoximine (BSO) on the level of DNA adducts. We found that pretreatment of MNCs with 150 μM BSO for 2 h prior to BPDE exposure increased the level of BPDE‐DNA adducts appreciably (by ∼70%). Further investigations revealed that the 2‐h BSO treatment neither decreased the GSH level instantly nor affected GST activity; rather, it prevented the induction of GSH in response to subsequent BPDE incubation. The blocked synthesis of GSH might be responsible for the elevated level of BPDE‐DNA adducts in MNCs after BSO and BPDE treatment.