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

Abstract

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 microM BSO for 2 h prior to BPDE exposure increased the level of BPDE-DNA adducts appreciably (by approximately 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.

2D Graphene Oxide/Fe-MOF Nanozyme Nest with Superior Peroxidase-Like Activity and Its Application for Detection of Woodsmoke Exposure Biomarker

“…Thus, ultrasensitive analysis of BPDE–DNA is significant for the assessment and prevention of cancer risk at an early stage. Approaches to quantify the level of BPDE–DNA in blood include high performance liquid chromatography (HPLC) and gas/liquid chromatography–mass spectrometry (GC/LC-MS), both of which are extremely costly, time-consuming, and unreachable for onsite/household assessment. , Immunoassays, including ELISA, lateral flow immunoassays, and nanomaterial-based immunoassays, offer rapid and convenient alternatives to chromatography for BPDE–DNA detection. − A validation of an immunoassay-based capillary electrophoresis-laser-induced fluorescence (CE-LIF) method to analyze the concentration of BPDE–DNA in blood was reported by LeBlanc et al in 2009 . Wang and co-workers designed an immunoassay employing fluorescence imaging to count the amount of OliGreen dye specifically adsorbed to ssDNA for the quantification of BPDE–DNA .…”

Exposure of sea bream (Sparus aurata) to toxic concentrations of benzo[a]pyrene: possible human health effect

“…9, the maximum GSH depletion was observed in cells exposed to FOE obtained from fish exposed to B (Kiruthiga et al, 2010). Although GSH conjugation of B[a]P activated metabolites is believed to be an important mechanism in detoxification of this environmental and dietary carcinogen (Srivastava et al, 2002), the depletion of GSH may shift the cell redox status towards oxidative stress, and has deep effects on different cellular systems (LeBlanc et al, 2009). Taken together, these findings evidence that exposure of blood cells to B[a]P through fresh fish products, at a level achievable through the human daily diet, induces only a modest toxic effect (as demonstrated by the significant depletion in intracellular GSH content in absence of changes in cell viability), and thus seem to suggest that exposure to B[a]P through this kind of food is not a major health problem for consumers.…”

Capillary electrophoresis–based immunoassay and aptamer assay: A review

“…The resultant limit of detection was 3 nM . Since that time, this format has been widely used for example for analyzing hormones , proteins , peptides , DNA adducts , and also to check for drugs and their abuse . In several publications, a thermally reversible hydrogel was used as a buffer additive to improve reproducibility .…”

“…In several publications, a thermally reversible hydrogel was used as a buffer additive to improve reproducibility . More details about the practical applications of this format are summarized in Table .…”