Baicalein Significantly Protects Human Retinal Pigment Epithelium Cells Against H2O2-Induced Oxidative Stress by Scavenging Reactive Oxygen Species and Downregulating the Expression of Matrix Metalloproteinase-9 and Vascular Endothelial Growth Factor

Abstract Purpose: Age-related macular degeneration is a leading cause of blindness in the elderly. At a later stage, neovascular or exudative age-related macular degeneration can lead to severe central vision loss that is related to aging-associated cumulative oxidative stress of the human retinal pigment epithelium (hRPE) cells. Early prevention with antioxidants is mandatory. The aim of this study was to determine whether and how baicalein can act as an antioxidant. Methods: The methods used included lactate dehydrogenase, 2′,7′-dichloro-fluorescein diacetate, or enzyme-linked immunosorbent assay to measure cell viability, oxygen free radical levels, or the levels of vascular endothelial growth factor (VEGF)/matrix metalloproteinase-9 (MMP-9), respectively. Results: H2O2 dose-dependently reduced the cell viability of hRPE cells. This negative effect was dose-dependently (with a lower effect at 20 μM) and significantly counteracted by pretreatment with baicalein (50 μM). Treatment with H2O2 significantly...