Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2011
Publication Date: 3/29/2012
Citation: Traber, M.G., Leonard, S.W., Fu, X., Grusak, M.A., Booth, S.L. 2012. Plasma alpha-tocopherol transport studied using deuterium-labeled collard greens [abstract]. Journal of Federation of American Societies for Experimental Biology. 26:365.5. Interpretive Summary:
Technical Abstract: To evaluate the bioavailability and plasma transport of deuterium labeled (d)-alpha-tocopherol (aT) from food, we used collard greens grown in deuterated water as a source of d-aT. A single serving of 120 g steamed d-collard greens (1.2 +/- 0.1 mg d-aT) was eaten by each of 20 healthy adults with a standard breakfast; blood samples were obtained up to 72 h. Plasma aT concentrations were measured using LC/MS in negative mode; the ion abundances of daT and unlabeled aT were determined using selected ion monitoring to detect d-aT isotopomers; predominant one were m/z 438-442. The (m/z 438-442)/(m/z 434-446) ratio was 0.63 in collard greens, which was used to correct the plasma d-aT abundance. Peak plasma d-aT concentrations (250 +/- 130 nmol/L; 1.2% +/- 0.6% total a-T) occurred at 9 to 16 h with an estimated absorption of ~36%. The post-peak exponential disappearance rate was 0.6 +/- 0.2 pools/d, equivalent to a half-life of 29 +/- 8 h. This is the first time that aT bioavailability from food with naturally incorporated d-aT has been measured. Our findings confirm the relatively limited absorption and slow plasma disappearance of physiologic d-aT doses.