Detection of DNA adducts derived from the reactive metabolite of furan, cis-2-butene-1,4-dial.
Furan is a toxic and carcinogenic compound used in industry and commonly found in the environment. The mechanism of furan's carcinogenesis is not well-understood and may involve both genotoxic and nongenotoxic pathways. Furan undergoes oxidation by cytochrome P450 to cis-2-butene-1,4-dial, which is thought to mediate furan's toxic effects. Consistently, cis-2-butene-1,4-dial readily reacts with glutathione, amino acids, and nucleosides. To determine the importance of DNA alkylation in furan-induced carcinogenesis, we developed an assay for the detection of cis-2-butene-1,4-dial-derived DNA adducts. DNA samples were treated with O-benzyl-hydroxylamine, which reacts with the aldehyde functionality of the DNA adducts. Enzyme hydrolysates of these samples were then analyzed by capillary electrospray tandem mass spectrometry with selected reaction monitoring. The dCyd and dAdo adducts were detected in digests of DNA treated with nanomolar concentrations of cis-2-butene-1,4-dial. In addition, these adducts were present in DNA isolated from Ames assay strain TA104 treated with mutagenic concentrations of cis-2-butene-1,4-dial. These data support the hypothesis that cis-butene-1,4-dial is a genotoxic metabolite of furan. This method will allow us to explore the role of these adducts in furan-induced carcinogenesis.
Division of Environmental Health and Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Michael C
MC
Byrns
Choua C
CC
Vu
Jonathan W
JW
Neidigh
José-Luis
JL
Abad
Roger A
RA
Jones
Lisa A
LA
Peterson
D000447:Aldehydes / Q000032:analysis* / Q000633:toxicity; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000737:chemistry / Q000187:drug effects; D018736:DNA Adducts / Q000032:analysis; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D012015:Reference Standards; D012486:Salmonella typhimurium / Q000187:drug effects / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet
D000447:Aldehydes; D018736:DNA Adducts; D007202:Indicators and Reagents; C015977:malealdehyde; D004247:DNA