Lutein and zeaxanthin isomers ameliorate photoreceptor degeneration in Pde6^rd10 mice

Abstract

Purpose : Oxidative stress and endoplasmic reticulum stress are major factors underlying photoreceptor degeneration. Lutein and zeaxanthin isomers (L/Zi), consisting of lutein, zeaxanthin and mesozeaxanthin carotenoids, are found widely in many foods and protect against cell damage by ameliorating oxidative stress in retina. In this study, we examined the effect of L/Zi supplementation in a mouse model of retinitis pigmentosa with photoreceptor degeneration.

Methods : L/Zi (10 mg/kg body weight) dissolved in sunflower oil (SFO, 1 mg/ml) or equal volume of SFO as vehicle was administered by daily oral gavage to the Pde6^rd10 (rd10) mice in treatment group (n=5) and vehicle group (n=6), respectively from P6 to P20. ERG was tested to show the functional change of retina. GRP78 and ERp29 were tested by western blot and immunostaining in the in treatment group (n=4) and vehicle group (n=4).

Results : ERG amplitudes were significantly higher in the L/Zi treated group than in the vehicle control group. GRP78 was downregulated and ERp29 was upregulated by L/Zi treatment.

Conclusions : Treatment with L/Zi can ameliorate photoreceptor degeneration in rd10 mice. This treatment effect is probably related to the decrease of oxidative stress and endoplasmic reticulum stress by the L/Zi treatment. Future studies will examine the potential for L/Zi in other inherited forms of photoreceptor degeneration involving oxidative stress and endoplasmic reticulum stress.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.