DNA methylation by dimethyl sulfoxide and methionine sulfoxide triggered by hydroxyl radical and implications for epigenetic modifications.
ABSTRACT In this Letter, we demonstrate the formation of m(5)dC from dC or in DNA by dimethylsulfoxide (DMSO) and methionine sulfoxide (MetO), under physiological conditions in the presence of the Fenton reagent in vitro. DMSO reportedly affects the cellular epigenetic profile, and enhances the metastatic potential of cultured epithelial cells. The methionine sulfoxide reductase (Msr) gene was suggested to be a metastatis suppressor gene, and the accumulation of MetO in proteins may induce metastatic cancer. Our findings are compatible with these biological data and support the hypothesis that chemical cytosine methylation via methyl radicals is one of the mechanisms of DNA hypermethylation during carcinogenesis. In addition to m(5)dC, the formation of 8-methyldeoxyguanosine (m(8)dG) was also detected in DNA under the same reaction conditions. The m(8)dG level in human DNA may be a useful indicator of DNA methylation by radical mechanisms.
- SourceAvailable from: Frederick E Domann[show abstract] [hide abstract]
ABSTRACT: Epigenetic modifications represent mechanisms by which cells may effectively translate multiple signaling inputs into phenotypic outputs. Recent research is revealing that redox metabolism is an increasingly important determinant of epigenetic control that may have significant ramifications in both human health and disease. Numerous characterized epigenetic marks, including histone methylation, acetylation, and ADP-ribosylation, as well as DNA methylation, have direct linkages to central metabolism through critical redox intermediates such as NAD(+), S-adenosyl methionine, and 2-oxoglutarate. Fluctuations in these intermediates caused by both normal and pathologic stimuli may thus have direct effects on epigenetic signaling that lead to measurable changes in gene expression. In this comprehensive review, we present surveys of both metabolism-sensitive epigenetic enzymes and the metabolic processes that may play a role in their regulation. To close, we provide a series of clinically relevant illustrations of the communication between metabolism and epigenetics in the pathogenesis of cardiovascular disease, Alzheimer disease, cancer, and environmental toxicity. We anticipate that the regulatory mechanisms described herein will play an increasingly large role in our understanding of human health and disease as epigenetics research progresses.Antioxidants & Redox Signaling 10/2010; 15(2):551-89. · 8.20 Impact Factor
- Radiotherapy and Oncology - RADIOTHER ONCOL. 01/2011; 99.