Arch Biochem Biophys. 2003 Aug; 416(2): 196-201.

Black tea extract supplementation decreases oxidative damage in Jurkat T cells.

Erba D, Riso P, Foti P, Frigerio F, Criscuoli F, Testolin G.

Department of Food Science and Microbiology, University of Milan, Via Celoria, 2, 20133 Milan, Italy. daniela.erba@unimi.it

The purpose of this study was to investigate the protective effect of black tea (BT) extract against induced oxidative damage in Jurkat T-cell line. Cells supplemented with 10 or 25 mg/L BT were subjected to oxidation with ferrous ions. Malondialdehyde (MDA) production as marker of lipid peroxidation, DNA single strand breaks as marker of DNA damage, and modification of the antioxidant enzyme activity, glutathione peroxidase (GPX) were measured. Results show the efficacy of BT polyphenols to decrease DNA oxidative damage and to affect GPX activity (P<0.05), while no effect was shown on MDA production. The succeeding investigation of the activity of caffeine and epigallocatechin gallate demonstrated their antioxidant potential with respect to the cellular markers evaluated. In conclusion, this study supports the protective effect of BT against ferrous ions induced oxidative damage to DNA and the ability of BT to affect the enzyme antioxidant system of Jurkat cells.