Elimination of Deleterious Effects of Free Radicals in Murine Skin Carcinogenesis byBlack Tea Infusion, Theaflavins & Epigallocatechin Gallate

Abstract

In recent years, numerous reports have been published on the identification of novel, naturally occurring ‍antioxidants from plants, animals, microbial sources and processed food products. Most natural antioxidants are ‍phenolic compounds, which have a modulatory role on physiological functions and biotransformation reactions ‍involved in the detoxification process, thereby affording protection from cytotoxic, genotoxic and metabolic actions ‍of environmental toxicants. As part of our program on evaluation of food, beverage and traditional medicinal plants ‍for their anticarcinogenic activity, the present report deals with the evaluation of aqueous infusion of Black tea ‍(Camellia sinensis), Black tea extract (80% Theaflavins) & EGCG on mice exposed to the chemical carcinogen ‍DMBA. All the four detoxification enzymes studied viz, GST, GPx, SOD and CAT were found to be activated to ‍different degrees following treatment with black tea and two of its active compounds. The activation of the enzymes ‍was accompanied by significant reduction in lipid peroxidation. The effect on apoptosis and cell proliferation was ‍also studied in mice skin following administration of DMBA. Theaflavins, and EGCG significantly inhibited cell ‍proliferation and induced apoptosis. The observation suggests chemopreventive potential of black tea infusion, ‍black tea extract Theaflavins and the compound EGCG.‍

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