Cigarette smokers differ in their handling of natural (RRR) and synthetic (all rac) α-tocopherol: A biokinetic study in apoE4 male subjects

We have compared the biokinetics of deuterated natural (RRR) and synthetic (all rac) α-tocopherol in male apoE4-carrying smokers and nonsmokers. In a randomized, crossover study subjects underwent two 4-week treatments (400 mg/day) with undeuterated RRR- and all rac-α-tocopheryl acetate around a 12-week washout. Before and after each supplementation period subjects underwent a biokinetic protocol (48 h) with 150 mg deuterated RRR- or all rac-α-tocopheryl acetate. During the biokinetic protocols, the elimination of endogenous plasma α-tocopherol was significantly faster in smokers (P < 0.05). However, smokers had a lower uptake of deuterated RRR than nonsmokers, but there was no difference in uptake of deuterated all rac. The supplementation regimes significantly raised plasma α-tocopherol (P < 0.001) with no differences in response between smokers and nonsmokers or between α-tocopherol forms. Smokers had significantly lower excretion of α-carboxyethyl-hydroxychroman than nonsmokers following supplementation (P < 0.05). Nonsmokers excreted more α-carboxyethyl-hydroxychroman following RRR than all rac; however, smokers did not differ in excretion between forms. At baseline, smokers had significantly lower ascorbate (P < 0.01) and higher F2-isoprostanes (P < 0.05). F2-isoprostanes in smokers remained unchanged during the study, but increased in nonsmokers following α-tocopherol supplementation. These data suggest that apoE4-carrying smokers and nonsmokers differ in their handling of natural and synthetic α-tocopherol.