Chlorella vulgaris, a green algae, protects against retinal degeneration in vitro and in vivo

Abstract

This study aimed to examine whether the extract of Chlorella vulgaris (ECV) could attenuate against retinal degeneration. Oxidative stress was evoked in transformed retinal ganglion cells (RGC-5) by L-buthionine-(S,R)-sulfoximine (BSO) plus glutamate. Cell viability decreased after exposure of BSO plus glutamate in RGC-5 cells, however, pre-treatment of ECV attenuated cell death in a concentration-dependent manner. The up-regulated expression of cleaved PARP, caspase-9, and caspase-3 caused by BSO plus glutamate was dose-dependently attenuated by the pre-treatment of ECV. To induce in vivo retinal degeneration in rat, we administered N-methyl-D-aspartate (NMDA) by intravitreal injection. NMDA to the retina affected the thickness of inner plexiform layer (IPL) and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) positive cells in ganglion cell layer (GCL). Importantly, the thinning of IPL and increased TUNEL positive cells were attenuated by ECV. These findings indicate that ECV can protect retinal cells from oxidative stress-induced damages in vitro and in vivo, suggesting that C. vulgaris may be used as a useful supplement to prevent retinal degeneration.