Contribution of hydrogen peroxide to the cytotoxicity of green tea and red wines.
Green tea and red wine are claimed to have health benefits because of their high content of polyphenolic compounds, but they have also been reported as mutagenic in some test systems. In this paper, we show that a commonly used cell culture medium, Dulbecco's modified Eagle's medium (DMEM), catalyses oxidation of green tea and red wines to generate H(2)O(2). The level of H(2)O(2) produced from green tea accounted for all of the cytotoxic effects of this beverage on PCl2 cells. By contrast, H(2)O(2) was only responsible for part of the cytotoxicity of the red wines examined. Our data illustrate the danger of extrapolating from cell culture studies to predict the effects of complex beverages in vivo.
Department of Biochemistry, Faculty of Medicine, National University of Singapore MD 7 #03-08, 8 Medical Drive, Singapore 117597, Singapore.
Phing Chian
PC
Chai
Lee Hua
LH
Long
Barry
B
Halliwell
D000818:Animals; D001628:Beverages / Q000633:toxicity*; D002374:Catalase / Q000378:metabolism; D002470:Cell Survival / Q000502:physiology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D016877:Oxidants / Q000378:metabolism*; D010084:Oxidation-Reduction; D016716:PC12 Cells; D010936:Plant Extracts / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D051381:Rats; D013662:Tea / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity*; D014920:Wine / Q000633:toxicity*
D016877:Oxidants; D010936:Plant Extracts; D013662:Tea; D006861:Hydrogen Peroxide; D002374:Catalase