Effect of dietary zeaxanthin on tissue distribution of zeaxanthin and lutein in quail.
OBJECTIVE
The xanthophyll carotenoids (lutein and zeaxanthin) are hypothesized to delay progression of age-related macular degeneration. The quail has a cone-dominant retina that accumulates carotenoids. The purpose of these experiments was to characterize the carotenoid composition of retina, serum, liver, and fat in quail and to determine whether dietary enrichment with zeaxanthin alters zeaxanthin or lutein concentrations in these tissues.


METHODS
Quail were fed for 6 months with a commercial turkey diet (T group; n = 8), carotenoid-deficient diet (C- group; n = 8), or a carotenoid-deficient diet supplemented with 35 mg 3R,3'R-zeaxanthin per kilogram of food, (Z+ group; n = 8). Zeaxanthin was derived from Sphingobacterium multivorum (basonym Flavobacterium). Carotenoids in serum, retina, liver, and fat were analyzed by HPLC.


RESULTS
As in the primate fovea, the retina accumulated zeaxanthin, lutein, and cryptoxanthin, and preferentially absorbed zeaxanthin (P < 0.005). In contrast, lutein was preferentially absorbed by liver (P < 0.01) and fat (P < 0.0001). In supplemented females, zeaxanthin increased approximately 4-fold in retina, and 74-, 63- and 22-fold in serum, liver, and fat, respectively. In males, zeaxanthin was elevated approximately 3-fold in retina, and 42-, 17-, and 12-fold in serum, liver, and fat, respectively. Birds fed the Z+ diet absorbed a higher fraction of dietary lutein into serum, but lutein was reduced in the retina (P < 0.05).


CONCLUSIONS
Xanthophyll profiles in quail mimic those in primates. Dietary supplements of zeaxanthin effectively increased zeaxanthin concentrations in serum, retina, liver, and fat. The robust response to zeaxanthin supplementation identifies the quail as an animal model for exploration of factors regulating delivery of dietary carotenoids to the retina.
Toyoda
Yoko
Y
Schepens Eye Research Institute and Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA.
Thomson
Lauren R
LR
Langner
Andrea
A
Craft
Neal E
NE
Garnett
Kevin M
KM
Nichols
Cathleen R
CR
Cheng
Kimberly M
KM
Dorey
C Kathleen
CK
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003370:Coturnix / Q000378:metabolism*; D004032:Diet; D019587:Dietary Supplements; D007408:Intestinal Absorption; D008099:Liver / Q000378:metabolism; D014975:Lutein / Q000378:metabolism*; D012160:Retina / Q000378:metabolism; D014018:Tissue Distribution; D024341:Xanthophylls; D065146:Zeaxanthins; D019207:beta Carotene / Q000008:administration & dosage* / Q000031:analogs & derivatives / Q000378:metabolism*
D024341:Xanthophylls; D065146:Zeaxanthins; D019207:beta Carotene; D014975:Lutein