Objectives: It is well known that the carotenoids lutein (L) and zeaxanthin (Z) improve eye health and an accumulating evidence base suggests cognitive benefits as well. The present study investigated underlying neural mechanisms using functional magnetic resonance imaging (fMRI). It was hypothesized that lower L and Z concentrations would be associated with neurobiological inefficiency (i.
View Article and Find Full Text PDFBackground: Increased consumption of lutein and zeaxanthin has been shown to increase macular pigment optical density (MPOD) in some individuals. Most interventions either obtained infrequent measures of MPOD or measured MPOD at a single retinal locus.
Purpose: The aim of this study was to measure acute changes in MPOD at four retinal loci during lutein intervention.
Purpose: To determine whether anthocyanin-enriched bilberry extracts modulate pre- or posttranslational levels of oxidative stress defense enzymes heme-oxygenase (HO)-1 and glutathione S-transferase-pi (GST-pi) in cultured human retinal pigment epithelial (RPE) cells.
Methods: Confluent ARPE-19 cells were preincubated with anthocyanin and nonanthocyanin phenolic fractions of a 25% enriched extract of bilberry (10(-6)-1.0 mg/mL) and, after phenolic removal, cells were oxidatively challenged with H(2)O(2).
Light absorption by macular pigment may attenuate visual discomfort, or photophobia, for targets composed of short-wavelength light. Macular pigment optical density (MPOD) and photophobia light thresholds were measured psychophysically in 10 subjects. The energy necessary to induce photophobia for a short-wavelength target relative to a long-wavelength target was linearly related to MPOD, as well as estimates of peak MPOD and integrated macular pigment.
View Article and Find Full Text PDFJ Agric Food Chem
October 2006
Increasing intakes of carotenoid-rich plant foods can increase serum carotenoid concentrations and macular pigment optical density (MPOD) in most, but not all, individuals. Research objectives for this study were to (1) characterize tissue lutein (L) and beta-carotene (BC) concentrations in carotenoid-rich spinach (Spinacia oleracea L.) cultigens and (2) determine serum carotenoid and MPOD responses in human subjects consuming spinach cultigens differing in tissue L and BC concentrations.
View Article and Find Full Text PDFTwo carotenoids found in egg yolk, lutein and zeaxanthin, accumulate in the macular retina where they may reduce photostress. Increases in serum lutein and zeaxanthin were observed in previous egg interventions, but no study measured macular carotenoids. The objective of this project was to determine whether increased consumption of eggs would increase retinal lutein and zeaxanthin, or macular pigment.
View Article and Find Full Text PDFThe dietary carotenoids lutein (L) and zeaxanthin (Z) are the principal components of macular pigment (MP). Protection of the central retina by MP is suggested, but data are limited. Dietary practices and serum carotenoid concentrations were investigated in 98 adults, 45-73 y old, in relation to MP.
View Article and Find Full Text PDFDietary intake of certain carotenoids has been associated with a reduced risk of disease. Kale (Brassica oleracea L. Acephala Group) has the highest levels of carotenoids lutein and beta-carotene, and is an excellent source of minerals among the green leafy vegetable crops.
View Article and Find Full Text PDFOf the many carotenoids found within human tissue, only the carotenoids within the human retina can be assessed noninvasively at present. Such assessment should eventually provide a more complete understanding of the functional role of retinal lutein (L) and zeaxanthin (Z) (termed macular pigment, MP) in human vision. The emerging data allow for some initial observations.
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