Abstract
Purpose :
Sea buckthorn is a plant that belongs to the Elaeagnaceae family. It produces yellow or orange berries that are abundant in vitamins, minerals, amino acids, flavones, and fatty acids. Recent studies have shown that sea buckthorn seeds and pomace exhibit neuroprotective effects against light-induced retinal degeneration in rabbits. However, the effect of sea buckthorn juice remains unclear. In this study, we aimed to compare the neuroprotective effects of oil- and water-soluble fractions of sea buckthorn juice against light-induced retinal degeneration in rats.
Methods :
Sea buckthorn berries were crushed and separated into juice and pomace. The juice was then separated into oil-soluble fraction (OSF) and water-soluble fraction (WSF) by centrifugation. The fractions were orally administered at doses of 150 mg/kg (low) and 500 mg/kg (high) to 8-week-old male Sprague—Dawley rats before and 12 h after light exposure (7000 lux for 24 h). Photoreceptor function was evaluated by determining the amplitude of the b-wave of electroretinogram on the day after light exposure. To assess retinal structure, the thickness of the outer nuclear layer (ONL) was measured using optical coherence tomography seven days after light exposure.
Results :
Light exposure reduced the amplitude of b-wave, while treatment with low- and high-dose OSF retained high b-wave amplitude in a dose-dependent manner. The high OSF group (821.9±448.3 µV, p<0.01) demonstrated a significant neuroprotective effect when compared with the vehicle group. The low WSF (369.7±249.1 µV) and high WSF (245.0±265.9 µV) groups did not exhibit neuroprotective effects when compared with the vehicle group (419.5±195.0 µV). Structural analysis showed that light exposure decreased the thickness of ONL, while treatment with high-dose OSF (47.0±13.7 µm, p<0.05) retained significantly higher ONL thickness than the vehicle group. The low WSF (42.0±13.6 µm) and high WSF (30.4±10.9 µm) groups did not show neuroprotective effects when compared with the vehicle group (39.8±11.7 µm).
Conclusions :
As the OSF of sea buckthorn juice showed potent neuroprotective effects by suppressing photoreceptor cell death, it may be used as a potential diet-based approach for the treatment of age-related macular degeneration.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.