Analysis of crotonaldehyde- and acetaldehyde-derived 1,N2-propanodeoxyguanosine adducts in DNA from human tissues using liquid chromatography-electrospray ionization-tandem mass spectrometry

TOXI 95

Siyi Zhang, zhan0505@umn.edu1, Peter W. Villalta, villa001@umn.edu2, Mingyao Wang, wangx126@umn.edu2, and Stephen S. Hecht, hecht002@umn.edu2. (1) Department of Medicinal Chemistry and The Cancer Center, University of Minnesota, 420 Delaware St SE - MMC 806, Minneapolis, MN 55455, (2) University of Minnesota Cancer Center, 420 Delaware St SE - MMC 806, Minneapolis, MN 55455
Crotonaldehyde, a mutagen and carcinogen, reacts with deoxyguanosine (dGuo) to generate diastereomeric 1,N2-propanodeoxyguanosine (Cro-dG) adducts. They can also be formed through the consecutive reaction of two acetaldehyde molecules with dGuo. Considering the importance of DNA adducts in carcinogenesis, we have developed a sensitive and specific LC-ESI-MS/MS method to explore the presence of Cro-dG adducts in DNA from various human tissues. DNA isolated from human tissues was enzymatically hydrolyzed in the presence of [15N5]Cro-dG as an internal standard. The Cro-dG adducts were enriched from the hydrolysate by solid phase extraction and analyzed by LC-ESI-MS/MS, using selected reaction monitoring. This method allows the quantitation of the Cro-dG adducts at concentrations of 4 fmol/µmol dGuo starting with 1 mg of DNA. Using this method, DNA from human liver, lung and blood were analyzed. The Cro-dG adducts were detected more frequently in human lung DNA than in liver DNA. The results from this study demonstrated the presence of these adducts in human tissues and the differences between liver and lung DNA require further study.
 

General Papers
9:00 AM-11:30 AM, Wednesday, 13 September 2006 Moscone Center -- Room 308, Oral

Division of Chemical Toxicology

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006