alpha-tocopherol dietary supplement decreases titers of antibody against 5-hydroxymethyl-2 '-deoxyuridine (HMdU)

This study evaluated the effects of vitamin E (alpha-tocopherol) on oxidati ve DNA damage in a randomized double-blind Phase II chemoprevention trial. Oxidative DNA damage was measured by the level of auto-antibody (Ab) agains t 5-hydroxymethyl-2'-deoxyuridine (HMdU) in plasma, After the baseline scre ening, eligible subjects (n = 3); plasma samples from 28 subjects were avai lable for this study) were randomized to receive 15, 60, or 200 mg of alpha -tocopherol per day for 28 days. Biomarkers were measured twice at baseline -on day 1 (visit 1) and day 3 (visit 2)-and twice after intervention-on day 17 (visit 3) and day 31 (visit 4), At baseline, there was a highly signifi cant inverse correlation between anti-HMdU Ab titer and plasma vitamin E le vel (r = -0.53; P = 0.004; n = 28). Smoking did not affect baseline anti-HM dU Ab titer; however, anti-HMdU Ab titer Levels at baseline were significan tly lower in subjects with above-median (0.75 ounce/day) alcohol consumptio n (P = 0.008). No significant change in anti-HMdU Ab level occurred at eith er visit 3 or visit 4 for subjects on the lowest dose, 15 mg alpha-tocopher ol per day, Subjects receiving 60 mg of alpha-tocopherol per day had a sign ificant decrease in anti-HMdU Ab level at visits 3 and 4 compared with base line (P = 0.049 and P = 0.02, respectively). However, subjects receiving th e highest dose, 200 mg/day, had less consistent results: a significant decr ease in anti-HMdU Ab level was seen at visit 4 (P = 0.04) but not at visit 3, Our results demonstrate an inverse relationship between alpha-tocopherol and anti-HMdU Abs in plasma; oxidative DNA damage an be modulated by short -term dietary supplementation of alpha-tocopherol in some subjects.