Abstract
Bilberry (Vaccinium myrtillus) is herbaceous perennial and a native of North Europe, and the fruit shows dark-blue or purple-black color. Bilberry extracts have been utilized as a popular supplement for asthenopia and recovery of visual function. However, the pharmacologic affects and the mechanism of action have not been investigated. On the other hand, glaucoma and diabetic retinopathy are representative ocular diseases of visual loss in Japan. These ocular diseases relate on retinal damage and neovascularization in retina. Therefore, we examined the effects of bilberry extracts on 1) retinal ganglion cell (RGC) damage and 2) retinal angiogenesis using in vitro and in vivo models.
1) Bilberry extracts and its main constituents, anthocyanidin (delphinidin, cyanidin, and malvidin), inhibited peroxynitrite (reactive oxygene species : ROS) -induced radical activation and the cell death of RGC-5 (a rat ganglion cell-line transformed using E1A virus). Furthermore, intravitreous injection of bilberry extracts inhibited N-methyl-D-aspartic acid (NMDA) -induced retinal damage in mice.
2) Bilberry extracts inhibited vascular endothelial growth factor (VEGF) -induced tube formation, proliferation, and migration of human umbilical vein endothelial cells (HUVECs). Furthermore, intravitreous injection of bilberry extracts inhibited the neovascular tufts of oxygen-induced retinopathy in mice.
These findings indicate the possibility that bilberry extracts are useful in the prophylaxis and therapy against ocular diseases such as retinal damage and neovascularization.
