Document Type


Publication Date


Publication Title

Proceedings of the National Academy of Sciences of the United States of America


Department of Chemistry


The role of glutathione and cytochrome P-450 in the production of DNA damage by chromium(VI) was examined in chicken embryo hepatocytes by the alkaline elution technique. Cellular levels of glutathione and cytochrome P-450 were altered by treating the hepatocytes with N-acetyl-L-cysteine, buthionine sulfoximine, isopentanol, or beta-naphthoflavone. A dramatic increase in chromium(VI)-induced DNA strand breaks was observed after increasing glutathione levels in the cells. Chromium(VI)-induced DNA strand breaks were even more numerous when the level of cytochrome P-450 was also increased. Upon depletion of glutathione levels and induction of cytochrome P-450 or cytochrome P-448, little or no DNA strand breaks or DNA interstrand cross-links were observed after chromium(VI) treatment. Chromium(VI)-induced DNA-protein cross-links generally decreased after either increases or decreases in cellular levels of glutathione or cytochrome P-450 or P-448. These results suggest that glutathione enhances chromium(VI)-induced DNA damage through metabolic activation of chromium(VI). The possible production of reactive chromium species upon metabolism by glutathione and cytochrome P-450 or P-448 and their involvement in DNA damage is discussed.

Original Citation

Cupo DY, Wetterhahn KE. Modification of chromium(VI)-induced DNA damage by glutathione and cytochromes P-450 in chicken embryo hepatocytes. Proc Natl Acad Sci U S A. 1985;82(20):6755-6759. doi:10.1073/pnas.82.20.6755