Gender-Dependent Mechanisms of Alpha-Tocopherol Protection from Benzo[a]pyrene Exposure in Rats

Thesis poster fair presentation.Polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene (BP), are environmental pollutants linked to increased disease susceptibilities. Alpha-Tocopherol (aT) supplementation decreases BP-DNA adducts in smokers, particularly women; but the mechanism is unknown. To test the hypothesis that aT protection from BP exposure is gender-dependent, male and female rats received 7 daily subcutaneous (SQ) injections of aT (100 mg aT/ kg body wt) or vehicle, followed by a single ip injection of BP (20 mg/kg, spiked with 3H-BP) on day 9. Urine and bile were collected pre- and post-BP. Plasma and tissues were collected 5 or 24 hr post-BP. aT supplementation increased aT levels in females greater than males. Compared to vehicle, aT supplementation increased total urinary and biliary excretion of BP and/or BP metabolites more than 2.5-fold in females, but decreased total BP and/or BP metabolite excretion in males (p