Lotus Seedpod Proanthocyanidins Protect Against Light-Induced Retinal Damage via Antioxidative Stress, Anti-Apoptosis, and Neuroprotective Effects.

BACKGROUND Over-exposure to visible white light can cause retinal damage. Lotus seedpod proanthocyanidins (LSPCs) possess a variety of biological activities, including potent antioxidant and protective effects. Herein, this study observed whether LSPCs can protect against light exposure-induced retinal damage. MATERIAL AND METHODS We randomly separated 40 Prague-Dawley rats into a control group, a light exposure-induced retinal injury model group, and low-dose (50 mg/kg), medium-dose (100 mg/kg), and high-dose (100 mg/kg) LSPCs groups. Light-induced retinal damage models were established by 5000±200 Lx light treatment for 6 h. Five days and 0.5 h before the light treatment, rats in the LSPCs groups were separately administered 50, 100, and 200 mg/kg LSPCs by gavage. After 7 days, H&E staining of retinal sections was performed and the thickness of the ONL was measured. Oxidative stress-related markers and antioxidant enzymes were measured in serum by biochemical testing. TUNEL staining of retinal sections was also performed. Apoptosis-relevant proteins were examined by RT-qPCR and western blotting. GFAP expression was examined with immunohistochemistry. RESULTS Our H&E staining showed that LSPCs can prevent retinal degeneration following light exposure. Histological analysis showed a significant reduction in the ONL thickness of light exposure-induced retinal injury rats, but LSPCs substantially improved the ONL thickness. LSPCs markedly ameliorated the light-induced increase in levels of MDA, NO, and NOS, and decrease in activity of GSH-Px and SOD. Moreover, LSPCs treatment alleviated light-induced retinal apoptosis and limited the light-induced increase in GFAP expression. CONCLUSIONS LSPCs effectively attenuated light-induced retinal damage through antioxidative stress, anti-apoptosis, and neuroprotective effects.