Bilberry anthocyanin-rich extract protects against retinal photooxidative damage via activation of HO-1 and inhibition of NF-κB

Abstract

Bilberry anthocyanins are functional ingredients for preventing retinal degeneration. This study was to determine whether the molecular mechanism of bilberry anthocyanin-rich extract (BAE) protection of retinal pigment epithelial (RPE) cells and retina against photooxidative damage via heme oxygenase-1 (HO-1) upregulation in vitro and in vivo. Results shown that BAE protected ARPE-19 cells from visible light-induced damage, reduced the intracellular reactive oxygen species levels, and up-regulated the expression of HO-1. Pigmented rabbits were treated with BAE (250 and 500 mg/kg/day) for 2 weeks pre-illumination and 1 week post-illumination until sacrifice. The expression of HO-1 in the retina was up-regulated after BAE treatment. BAE significantly suppressed the photooxidation-induced increase in expression of interleukine-6 protein. BAE also attenuated the expression of inflammation-related gene nuclear factor kappa B (NF-κB). Thus, BAE reduced retinal photooxidative damage through activating the HO-1 expression and suppressing NF-κB activation.

Keywords

• bilberry anthocyanins
• heme oxygenase-1
• nuclear factor-κb
• light-induced retinal degeneration
• retinoprotection
• retinal pigment epithelial cells