Anticancer Research - ۱۹۹۶

Crocetin is a major component in the fruit of Gardenia jasminoides Ellis, a Chinese herbal medicine. In the work, we investigate the protective action and mechanism against benzo(a)pyrene [B(a)P]-induced genotoxicity and neoplastic transformation with a non-toxic dose of crocetin (۰.۰۱-۰.۱۰ mM) for ۱ hour prior to the administration of ۰.۱ mM B(a)P. B(a)P genotoxicity was inhibited significantly by crocetin in a dose responsive manner. Pretreating C۳H۱۰T۱/۲ cells with crocetin (۰.۱ mM) also caused a decrease in the covalent binding of B(a)P-diol-epoxide to DNA, to about half that of cells without crocetin treatment. Crocetin also inhibited B(a)P-induced transformations. When the culture was treated with crocetin (۰.۰۱, ۰.۰۵ and ۰.۱۰ mM) for ۷ days, the transformation frequencies were lower than that of the culture without crocetin treatment. Furthermore, pretreating cells with crocetin (۰.۰۱-۰.۱۰ mM) also caused an increase in the activity of GSH S-transferase (GST) to ۱۸-۷۱% that of the cells without crocetin treatment. These results suggest that the inhibition by crocetin of B(a)P-induced genotoxicity and neoplastic transformation in C۳H۱۰T۱/۲ cells is due to a mechanism that increases the activity of GST and decreases the formation of a B(a)P-DNA adduct.