Modulation of hepatic cytochromes P450 and phase II enzymes by dietary doses of sulforaphane in rats: Implications for its chemopreventive activity.

The principal objectives of our study were to ascertain whether sulforaphane, at dietary levels of intake, modulates rat hepatic cytochrome P450 and phase II enzyme systems and to evaluate the impact of such changes in the chemopreventive activity of this isothiocyanate. Animals were exposed to sulforaphane in their drinking water for 10 days, equivalent to daily doses of 3 and 12 mg/kg. Depentylation of pentoxyresorufin decreased and was paralleled by a decline in CYP2B apoprotein levels.

Black tea intake modulates the excretion of urinary mutagens in rats exposed to 6-aminochrysene: induction of cytochromes P450 by 6-aminochrysene in the rat.

Rats were exposed to black tea (2.5% w/v) as their sole drinking liquid for either 1 day (short-term) or 1 month (long-term), while controls received water. After exposure, all animals received a single oral dose of 6-aminochrysene and urine was collected for 72 h.