Regulation of hazardous exposure by protective exposure: modulation of phase II detoxification and lipid peroxidation by Camellia sinensis and Swertia chirata.

Abstract

Many natural compounds are now known to 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 a programme on evaluation of food, beverage, and traditional medicinal plants for their anticarcinogenic activity, their effects on detoxification enzymes were also studied. The present report deals with Camellia sinensis and Swertia chirata. The effect of water infusions as well as crude and purified components of these plants on glutathione-S-transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) was analyzed in mice that were exposed to the chemical carcinogen DMBA. All the four enzymes were found to be activated in different degrees following treatment. The effect of Theaflavin, a component of black tea, was highly significant. The activation of the enzymes was accompanied by significant reduction in lipid peroxidation. The observation suggest the chemopreventive potential of both Camellia sinensis and Swertia chirata.