FLIO and the Influence of Oral Lutein Supplementation on Macular Pigment

The human macula is a small area of the retina responsible for central vision. The yellow macular pigment contains three carotenoids, lutein ((3R,3'R,6'R)-lutein), zeaxanthin ((3R,3'R)-zeaxanthin), and meso-zeaxanthin ((3R,3'S;meso)-zeaxanthin). The human body is unable to synthesize lutein and zeaxanthin, thus needs to be obtained from dietary sources such as green leafy vegetables and supplements. The function of the macular pigment is to act as a filter by absorbing blue light that may attenuate photochemical damage of the retina. Furthermore, it protects against light induced oxidative damage by functioning as an antioxidant; scavenging free radicals. A growing body of evidence has established a link between the concentrations of the macular pigment carotenoids, the macular pigment optical density (MPOD) levels, visual performance and the risk of macular degeneration.

The ability of the macular pigment to absorb or filter blue light can be measured as macular pigment optical density (MPOD), which is directly related to the quantity of lutein and zeaxanthin in the macula. Furthermore, preliminary data showed that macular pigment can be evaluated using Fluorescence lifetime imaging ophthalmoscopy (FLIO). In a previous study the investigators have shown that FLIO provides contrast for macular pigment in patients with AMD and healthy subjects.

The purpose of this study is to investigate the effects of oral lutein supplementation on macular pigment density using FLIO and MPOD measurements in healthy subjects and patients with age-related macular degeneration (AMD) over a course of 6 months. Furthermore, the investigators will assess whether compositional and functional alterations of the gut metagenome may be related to age-related macular degeneration, and the effects of lutein supplementation on the gut. In addition, to blood samples, stool samples will be analysed accordingly to the currently running study on "The role of the gut metagenome on the development of ophthalmic diseases" ClinicalTrials.gov Identifier: NCT02438111. Faecal analyses will provide insight to how oral lutein supplementation effects the gut microbiota and how it is influenced by serum lutein Levels.

Objective is to investigate the effects of lutein supplementation on macular pigment density using FLIO and MPOD measurements in patients with age-related macular degeneration and healthy subjects over a course of 6 months.