Sex differences in the inhibition of gamma-tocopherol metabolism by a single dose of dietary sesame oil in healthy subjects.
BACKGROUND
Gamma-tocopherol has unique properties that may be beneficial in sustaining optimal human health, but hepatic vitamin E metabolism enhances gamma-tocopherol turnover.


OBJECTIVE
Our aim was to determine the extent to which dietary sesame lignans alter human alpha- and gamma-tocopherol metabolism and elimination as carboxyethyl hydroxychromanols (CEHCs).


METHODS
Healthy participants (n = 5 women and 5 men) in a randomized, crossover study (with 4-wk washout) consumed muffins prepared with either corn oil or unrefined sesame oil (sesamin, 94 mg; sesamolin, 42 mg), along with a capsule containing a 1:1 molar ratio of deuterium-labeled d(6)-alpha- and d(2)-gamma-tocopherol acetates ( approximately 50 mg each). Plasma and urine were collected up to 72 h; unlabeled and labeled tocopherol and CEHC concentrations were determined by liquid chromatography-mass spectrometry.


RESULTS
Sesame oil muffin consumption in men, but not in women, decreased (P < 0.05) areas under plasma d(2)-gamma-CEHC concentration-time curves (area under the curve) and maximum concentrations. However, in both sexes urinary d(2)-gamma-CEHCs were decreased for 24 h following sesame oil muffin consumption.


CONCLUSIONS
In humans, gamma-tocopherol metabolism can be inhibited by the simultaneous consumption of gamma-tocopherol and sesame lignans. The observed differences between men and women with respect to vitamin E metabolism warrant further investigation.
Department of Food Science, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Jan
J
Frank
Sangeun
S
Lee
Scott W
SW
Leonard
Jeffrey K
JK
Atkinson
Afaf
A
Kamal-Eldin
Maret G
MG
Traber
D015992:Body Mass Index; D002853:Chromatography, Liquid; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D013058:Mass Spectrometry; D012016:Reference Values; D012715:Sesame Oil; D012727:Sex Characteristics; D024502:alpha-Tocopherol / Q000378:metabolism; D024504:gamma-Tocopherol / Q000008:administration & dosage / Q000378:metabolism*
D008055:Lipids; D012715:Sesame Oil; D024504:gamma-Tocopherol; D024502:alpha-Tocopherol