Recipient Organization
UNIVERSITY OF CALIFORNIA, DAVIS
410 MRAK HALL
DAVIS,CA 95616-8671
Performing Department
(N/A)
Non Technical Summary
Age-related macular degeneration (AMD) destroys the macula, the part of the retina that confers sharp, clear and color vision. The disease risk increases with age and affects women more than men. No options yet exist to reduce the risk of early AMD, but the dietary carotenoids lutein and zeaxanthin, which are concentrated in the macula, show promise, since they block damaging blue light and modulate oxidative stress. Goji berries contain the highest amount of zeaxanthin among all known dietary sources, and along with the lutein and a distinctive polysaccharide, may offer an approach to reduce the risk of AMD. We have recently shown that goji berry intake for 90 days significantly increased a biomarker of lutein and zeaxanthin in the macula in healthy adults. Here we propose to assess the effects of goji berry intake for 180 days among participants at-risk for AMD, and compare their multiple ocular outcomes to a control group consuming calorie- and fiber-matched gummies Our study will also profile gut microbiome changes using shallow shotgun metagenomic sequencing, assess differences in associated plasma microbial metabolites, and follow plasma levels of lutein and zeaxanthin. This three-year randomized clinical trial addresses the AFRI Program Area Priority "Food and Human Health" using a whole foods approach. If successful, the results can give consumers and health care providers new food-based options to reduce the risk of AMD and promote better eye health. The results may also stimulate development of goji berries as a viable specialty crop in the United States.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
Age-related macular degeneration (AMD) destroys the macula, the part of the retina that conferssharp, clear and color vision. The disease risk increases with age and affects women more thanmen. No options yet exist to reduce the risk of early AMD, but the dietary carotenoids lutein andzeaxanthin, which are concentrated in the macula, show promise, since they block damaging bluelight and modulate oxidative stress. Goji berries contain the highest amount of zeaxanthin amongall known dietary sources, and along with the lutein and a distinctive polysaccharide, may offer anapproach to reduce the risk of AMD. We have recently shown that goji berry intake for 90 dayssignificantly increased a biomarker of lutein and zeaxanthin in the macula in healthy adults. Herewe propose to assess the effects of goji berry intake for 180 days among participants at-risk forAMD, and compare their multiple ocular outcomes to a control group consuming calorie- and fibermatchedgummies Our study will also profile gut microbiome changes using shallow shotgunmetagenomic sequencing, assess differences in associated plasma microbial metabolites, and followplasma levels of lutein and zeaxanthin. This three-year randomized clinical trial addresses the AFRIProgram Area Priority "Food and Human Health" using a whole foods approach. If successful, theresults can give consumers and health care providers new food-based options to reduce the risk ofAMD and promote better eye health. The results may also stimulate development of goji berries asa viable specialty crop in the United States.
Project Methods
Participants will be randomized into a prospective, parallel-arm, unblinded trial to consume either 28g of organic goji berries or 28g or calorie- and fiber-matched gummies, five days per week for 180 days. The primary outcome, MPOD, along with the secondary measures of plasma L and Z, and other functional and anatomic ocular measures will be collected at baseline, and again at 90 and 180 days. Three-day food records will be collected within one week prior to each of the three study visits, and within one week of the day 45 and day 135 timepoints. Stool samples will be collected at home within one week of the day 0 and day 180 study visits.Twenty-eight grams of goji berries is considered a single serving. The control food will be gummies, matched to calorie and fiber content to 28g of goji berries.The primary outcome measure, MPOD will be assessed by the psychophysical method of heterochromatic flicker photometry using a macul.ar densitometer. Other visual function and anatomic assessments will include Best corrected visual acuity (BCVA), Low-luminance visual acuity (LLVA), Contrast sensitivity, Microperimetry, dark adaptometry and Spectral domain-optical coherence tomography.The gut microbiome composition will be analyzed using shallow shotgun metagenomic sequencing of stool.Analysis of lutein and zeaxanthin in the goji berries and plasma of participants will be conducted.Changes in MPOD and plasma L and Z over time will be examined using repeated measures regression models. Multivariate analyses of the microbiome data will be performed using Principal Coordinate Analysis. A two-sample t-test will be applied on the change from baseline to day 180 to assess the differences in change after intake of goji berries compared to the gummy control group. Spearman's correlations will be used to analyze the relationships between changes in dietary variables and changes in gut microbiome and microbial metabolite profiles, between changes in plasma L and L and changes in macular function-related outcomes, and between changes in gut microbiome and microbial metabolite profiles and changes in macular function outcomes.