Antioxidant effects of Yerba Mate tea.
Hogans-VJ; Coppes Petricorena-ZL; Harris-GK; Leonard-SS
Free Radicals in Montevideo, Montevideo, Uruguay, September 2-6, 2007. Montevideo, Uruguay: The Center for Free Radical and Biomedical Research - Uruguay, 2007 Sep; :125
Yerba Mate (llex paraguayensis) tea is indigenous to Paraguay, Argentina, Brazil and Uruguay and is cultivated in other South American countries. The tea is made from the leaves of the Yerba Mate holly tree. The native Indians of Paraguay and Brazil have used Yerba Mate for health remedies since before the sixteenth century. The tea is traditionally believed to promote perspiration, immunity, digestion, memory, and weight loss. Our research explored the antioxidant effects of Yerba Mate (YM) tea using a chemical reaction, enzymatic reaction, and radicals produced by Cr(VI)-stimulated RAW 264.7 cells. We also investigated YM tea's effect on cellular O2 consumption, DNA damage and lipid peroxidaton. YM tea samples were prepared using an infusion method and several concentrations were used to measure antioxidant effects. An electron spin resonance trapping technique was used to analyze free radicals and the effect of YM tea. Results showed a significant decrease in trapped hydroxyl radicals produced from the Fenton reaction after addition of all concentrations of YM tea. A significant, yet less dramatic, reduction in superoxide radicals generated from an enzymatic xanthine/xanthine oxidase reaction was also seen with all concentrations of YM tea in a concentration dependent manner. The presence of YM tea significantly reduced Cr(VI)-induced radical formation in RAW 264.7 cells in a concentration dependent manner. Controls and measurements which confirm scavenging of the radicals, rather than the inhibition of enzymatic reactions were performed in all assays. We also performed the following cellular assays using RAW 264.7 cells: measurement of O2 consumption, COMET assay for DNA damage, and the measurement of lipid peroxidation. Our results showed that YM tea reduced the amount of O2 consumed in cells after stimulation by exposure to Cr(VI). YM tea also inhibited .OH radical generated DNA damage in a concentration dependent manner and inhibited lipid peroxidation in H2O2-exposed cells. These data indicate that YM tea possesses potent antioxidant and DNA-protective activity, properties that are common to natural anti-cancer agents. This study may help to explain the mechanisms behind the reported antioxidant and anti-cancer effects of YM tea.
Organic-compounds; Cell-biology; Antigens; Antioxidants; Antioxidation; Lipid-peroxidation; DNA-damage
Abstract; Conference/Symposia Proceedings
Free Radicals in Montevideo, September 2-6, 2007, Montevideo, Uruguay
University of Pittsburgh at Pittsburgh