Suppressing effect of tannic acid on UV and chemically induced chromosome aberrations in cultured mammalian cells.

Abstract

UV-induced structural chromosome aberrations were suppressed by post-treatment with tannic acid (m-galoyl gallic acid) in cultured Chinese hamster ovary cells. A significant decrease in the frequencies of chromosome aberrations in the presence of tannic acid was observed in cells treated with mitomycin C or methylmethanesulfonate but not with X-rays or bleomycin. The effects of tannic acid were dependent on the DNA pre-replicational G1 phase of the cell cycle. Furthermore, tannic acid enhanced the liquid-holding effect on UV-irradiated cells at G1 phase. On the other hand, the number of surviving UV-irradiated cells increased in the presence of tannic acid. These results suggest the possibility of promotion by tannic acid of an excision repair system of mammalian cells.