Premium
Kinetics of 14 C distribution after tracer dose of 14 C‐lutein in an adult woman
Author(s) -
Moura Fabiana F.,
Ho Charlene C.,
Getachew Girma,
Hickenbottom Sabrina,
Clifford Andrew J.
Publication year - 2005
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/s11745-005-1471-4
Subject(s) - lutein , urine , feces , xanthophyll , chemistry , carotenoid , endocrinology , medicine , zoology , food science , biology , biochemistry , microbiology and biotechnology
Lutein is an oxygenated carotenoid (xanthophyll) found in dark green leafy vegetables. High intakes of lutein may lower the risk of age‐related macular degeneration. Current understanding of human lutein metabolism as it might occur in vivo is incomplete. Therefore, we conducted a feasibility study where we dosed a normal adult woman with 14 C‐lutein (125 nmol, 36 nCi 14 C), dissolved in olive oil (0.5 g/kg body weight) and mixed in a banana shake. Blood, urine, and feces collected before the dose was administered served to establish baseline values. There‐after, blood was collected for 63 d following the dose, while feces and urine were collected for 2 wk post‐dose. The 14 C contents in plasma, urine, and feces were measured by accelerator MS. The 14 C first appeared in plasma 1 h after dosing and reached its highest level,≈2.08% of dose/L plasma, at 14 h post‐dose. The plasma pattern of 14 C did not include a chylomicrons/VLDL (intestinal) peak like that when the same subject received 14 C‐β‐carotene (a previous test), suggesting that lutein was handled differently from β‐carotene by plasma lipoproteins. Lutein had an elimination half‐life ( t 1/2 ) of≈10 d. Forty‐five percent of the dose of 14 C was eliminated in feces and 10% in urine in the first 2 d after dosing. Quantifying human lutein metabolism is a fertile area for future research.