Abstract
Purpose :
To examine whether either free lutein or lutein esters supplementation affects macular pigment optical density and oxidative biomarkers.
Methods :
Subject: The study protocol was approved by the Ethics Committee of Shimane University and written informed consent was obtained from all subjects.
Twenty healthy subjects were recruited into this prospective, randomized, double-blind comparative study.
Methods: MPOD levels were measured by resonance Raman spectroscopy.
The serum lutein concentrations and MPOD levels were measured at baseline, 3 and 6 months after the start of supplementation.
Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured using the diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free-radical analyzer. Wilcoxon signed-rank test was used in the study.
Results :
In the macular pigment optical density (MPOD) levels, 3 months after the start of supplementation, the MPOD levels increased in both groups compared with baseline. After the end of supplementation, the MPOD levels remained elevated in both groups. In serum lutein concentration, at 3 months, the rate was 89% in the free lutein group and 97% in the lutein esters group, but there was no significant difference between the two groups. Compared with the 3rd month and 6th month, the ester type decreased significantly.
In BAP test, there is statistically significant difference between the baseline and after 6 months in free lutein type. There is no statistically significant difference any points the ester group.
In d-ROM test, there is no statistically significant difference any points the both group.
Conclusions :
The MPOD levels at 6 months were higher than at 3 months in both supplement groups, although the serum lutein concentrations decreased.
Although the mechanism of the result of SH and BAP tests is not known yet, lutein oral administration suppresses oxidative stress.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.