Interindividual variability of lutein bioavailability in healthy men: characterization, genetic variants involved, and relation with fasting plasma lutein concentration

Abstract

Background: Lutein accumulates in the macula and brain, where it is assumed to play physiologic roles. The bioavailability of lutein is assumed to display a high interindividual variability that has been hypothesized to be attributable, at least partly, to genetic polymorphisms. Objectives: We characterized the interindividual variability in lutein bioavailability in humans, assessed the relation between this variability and the fasting blood lutein concentration, and identified single nucleotide polymorphisms (SNPs) involved in this phenomenon. Design: In a randomized, 2-way crossover study, 39 healthy men consumed a meal that contained a lutein supplement or the same meal for which lutein was provided through a tomato puree. The lutein concentration was measured in plasma chylomicrons isolated at regular time intervals over 8 h postprandially. Multivariate statistical analyses were used to identify a combination of SNPs associated with the postprandial chylomicron lutein response (0-8-h area under the curve). A total of 1785 SNPs in 51 candidate genes were selected. Results: Postprandial chylomicron lutein responses to meals were very variable (CV of 75% and 137% for the lutein-supplement meal and the meal with tomato-sourced lutein, respectively). Postprandial chylomicron lutein responses measured after the 2 meals were positively correlated (r = 0.68, P , 0.0001) and positively correlated to the fasting plasma lutein concentration (r = 0.51, P , 0.005 for the lutein-supplement-containing meal). A significant (P = 1.9 3 10 24 )and validated partial least-squares regression model, which included 29 SNPs in 15 genes, explained most of the variance in the postprandial chylomicron lutein response. Conclusions: The ability to respond to lutein appears to be, at least in part, genetically determined. The ability is explained, in large part, by a combination of SNPs in 15 genes related to both lutein and chylomicron metabolism. Finally, our results suggest that the ability to respond to lutein and blood lutein status are related. This trial was registered at clinicaltrials.gov as NCT02100774. Am J Clin Nutr 2014;100:168-75.

A Combination of Single-Nucleotide Polymorphisms Is Associated with Interindividual Variability in Dietary β-Carotene Bioavailability in Healthy Men

“…Thirty-five healthy, nonobese, nonsmoking men were recruited for the study. This number was close to the number of subjects that allowed us to identify combinations of SNPs that were associated with both lutein (28) and vitamin E (29) bioavailability. Subjects reported normal energy consumption (i.e., ;2500 kcal/d) with <2% alcohol as total energy intake.…”

“…Chylomicrons were prepared from plasma samples as previously described (28,29,33,34). Immediately after recovery, chylomicrons were stored at 280°C before b-carotene analysis.…”

The urinary phenolic acid profile varies between younger and older adults after a polyphenol-rich meal despite limited differences in in vitro colonic catabolism

“…In older adults (40-50 years old), a higher urinary concentration of phenolic metabolites of anthocyanin such as syringic acid, p-coumaric acid, 4-hydroxybenzoic acid, and homovanillic acid was associated with higher bifidobacteria level (> 4.47 vs. < 1.18 log 10 copies per g faeces) [17]. Research into the bioavailability and metabolism of (poly)phenols, has so far been mostly limited to young adults [21][22][23][24][25][26], and inter-individual factors likely to impact on the outcome measures have rarely been studied in depth [27][28][29][30][31][32][33]. One study, in particular, looked at the effect of ageing on the absorption, metabolism, and excretion of epicatechin in healthy younger and older subjects after the consumption of cocoa flavanols, with little difference observed between subjects; the study did not, however, consider the colonic metabolism of epicatechin, or phenolic acids production [34].…”

A 3-hydroxy %-end group in xanthophylls is preferentially oxidized to a 3-oxo ε-end group in mammals

“…The postprandial response of lutein in chylomicrons showed large interindividual differences. The responses were related to single nucleotide polymorphisms in 15 genes known to participate in the intestinal absorption of lutein and chylomicron metabolism ( 41 ). It is most likely that genetic variants of an unknown dehydrogenase responsible for the oxidation of lutein to 3 ′ -hydroxy-, -caroten-3-one affect the long-term accumulations of lutein and zeaxanthin in human plasma, macula lutea, and other tissues.…”