Effects of Goji vs. Fiber on Macular Degeneration

Age-Related Macular Degeneration Clinical Trial

— GOJI  

Official title:

Effects of Goji Berry Intake on Risk of Age-related Macular Degeneration: A Randomized Clinical Trial

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06237127
• Other study ID #: 2082960
• Status: Recruiting
• Phase: N/A
• Start date: April 29, 2024
• Est. completion date: June 30, 2027

Study information

• Verified date: May 2024
• Source: University of California, Davis
• Contact: Denise Macias, CCRP
• Phone: (916) 734-6303
• Email: dcmacias[@]ucdavis.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The goal of this project is to conduct a clinical trial in 60 participants ranging from age 50-95 with small drusen who are at risk for age-related macular degeneration (AMD). The study will evaluate the effects of 28g of goji berry intake or an equivalent amount and type of fiber, five days a week for six months, on visual health, gut microbiome profiles, skin carotenoid measures, and lipoprotein profiles.

Description:

Age-related macular degeneration (AMD) is the third leading cause of blindness worldwide. The disease occurs when the macula in the central retina develops lesions due, in part, to the loss of the protection of macular pigments zeaxanthin, lutein, and meso-zeaxanthin, which are responsible for light filtering and oxidative defense. The major risk factor for AMD is aging, and currently, no definitive prevention for AMD exists.

Goji berry (Lycium Barbarum) is a fruit that has been used as traditional medicine in Asian countries for more than 2,000 years. Modern science has identified potential benefits of the berry in oxidant defense, immune regulation, diabetes, and vision in animal and cell models. Nonetheless, evidence regarding the effects of goji berries on human health is scarce. The bioactive components of goji berries include zeaxanthin, lutein, Lycium Barbarum polysaccharides-protein complex, betaine, cerebroside, minerals, and vitamins. Importantly, goji berries contain the highest concentration of zeaxanthin among all commonly consumed foods.

Previous clinical studies have shown that goji berries have a high bioavailability of zeaxanthin, and that macular pigment optical density (MPOD) was increased after supplementation. This study uses macular pigment optical volume (MPOV; a measure that integrates MPOD across multiple macular eccentricities) as the primary outcome measure. It is unknown if the changes in MPOV will be associated with other functional changes or anatomic conditions in the eye among a population with small drusen, a risk factor for AMD. In addition, the impact of goji berry intake on the gut microbiome profile and associated metabolites is unknown, and potentially important in understanding the mechanism(s) of action.

Participants who meet the eligibility criteria will be enrolled and will be randomized 1:1 to the goji berry arm or fiber arm of the study. Over the course of approximately 180 days, participants will consume the assigned food item five days per week and attend three study visits.

Study visits will include ophthalmic imaging and testing, skin carotenoid measurements, completion of a food record, height, weight, handgrip strength, blood pressure measurement, and fasting blood collection. At 2 timepoints participants will be asked to provide a stool sample (collected within 24 hours of visit).

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 60
• Est. completion date: June 30, 2027
• Est. primary completion date: June 30, 2026
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 50 Years to 95 Years

Eligibility

Inclusion Criteria:

• Diagnosis of small drusen by a retinal specialist

• Willingness and ability to comply with the study protocol

• 50 - 95 years of age

Exclusion Criteria:

• Dislike of, or allergy to, goji berries or any of the ingredients in the fiber-rich wafers and gummies (wheat, corn, oats, soy, natural orange flavor, xylitol, annatto, pectin, or other food ingredients)

• Consumption of > 2 alcoholic drinks per day

• Indications of substance or alcohol abuse

• Current or planned use of a blood thinner (e.g., Coumadin, Warfarin) at any time during study

• Use of multi-vitamin or any other supplements that contain lutein and/or zeaxanthin (if willing to stop the supplement, subject can be enrolled 6 months from stop date)

• Taking any new medications started within the past 6 months, or changes in medication regimen planned in the next 6 months (stable use greater than 6 months is not exclusionary)

• Any planned international travel during the study

• Consuming >3 servings/day of a combination of spinach, kale, lettuce, orange bell peppers, corn, parsley, squash, broccoli, pumpkin, edamame

• Regularly consuming >3 eggs/day

• Currently participating in any other interventional research study

• Diagnosed with inflammatory bowel disease, irritable bowel syndrome, other gastrointestinal disorder, undergoing cancer therapy or immunocompromised, or diagnosis of another condition where lutein, zeaxanthin and/or fiber supplementation would be contraindicated or would interfere with ability to participate in the study

• Any physical characteristic or condition that precludes ability to perform study procedures

• Medical or psychiatric condition that, in the opinion of the Investigator, would compromise study findings or prevent the participant from completing the study

Related Conditions & MeSH terms

• Age-Related Macular Degeneration
• Macular Degeneration

Intervention

Dietary Supplement:
• Goji berry
Participants will be instructed to consume 28 grams of goji berries 5 days a week for 6 months
• Fiber
Participants will be instructed to consume the fiber supplements 5 days a week for 6 months

Locations

Country	Name	City	State
United States	UC Davis Eye Center, Tschannen Eye Institute	Sacramento	California

Sponsors (2)

Lead Sponsor	Collaborator
University of California, Davis	United States Department of Agriculture (USDA)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Macular pigment optical volume (MPOV)	MPOV provides an objective measure of macular pigments by using dual wavelength autofluorescence using the Heidelberg Spectralis to obtain HRA + OCT measures	Day 0 and Day 180
Secondary	Stool microbiome	Metagenomic sequencing	Day 0 and Day 180
Secondary	Spectral Domain-Ocular Coherence Tomography (SD-OCT)	Central subfield thickness will be measured using the OCT instrument's algorithm	Day 0 and Day 180
Secondary	Fundus autofluorescence (FAF)	Blue FAF imaging will be performed to assess variations in lipofuscin autofluorescence	Day 0 and Day 180
Secondary	Color Fundus Photography (CFP)	CFP imaging uses a standard retinal camera.	Day 0 and Day 180
Secondary	Microperimetry testing	Microperimetry will be tested according to a standard protocol using a Nidek MP-1 instrument	Day 0 and Day 180
Secondary	Dark adaptometry	Dark adaptometry will be assessed using a standard protocol.	Day 0 and Day 180
Secondary	Plasma microbial metabolites	Biogenic amines will be measures by LC-MS	Day 0 and Day 180
Secondary	Plasma lutein and zeaxanthin	Plasma concentrations of lutein and zeaxanthin will be measured by LC-MS	Day 0 and Day 180
Secondary	Lipoprotein profile	Lipoprotein profiles will be measured according to standard protocols	Day 0 and Day 180
Secondary	HDL particle characteristics	Plasma will also be used to isolate and characterize HDL particles.	Day 0 and Day 180
Secondary	Peripheral blood mononuclear cells (PBMC) gene expression changes	PBMCs will be collected to monitor gene expression changes.	Day 0 and Day 180
Secondary	Cognitive function	Cognitive function will be assessed using web-based CANTAB tests	Day 0 and Day 180
Secondary	Handgrip strength	Handgrip strength will be measured using a Jamar hand dynamometer	Day 0 and Day 180