Camellia japonica hyperoside exhibits anti-age-related macular degeneration effects in an ARPE-19 cell model by inhibiting apoptosis via JNK-Nrf2/HO-1 activation

ETHNOPHARMACOLOGICAL RELEVANCE: Camellia japonica is recognized for its edible and therapeutic value in East Asia, and has anti-inflammatory, antioxidative, and antiasthmatic properties. However, the active compound and the modes of action are unclear. AIM OF THE STUDY: To evaluate the anti-AMD effect of hyperoside isolated from the leaves and twigs of Camellia japonica and to explore the underlying mechanisms using an ARPE-19 AMD cell model. MATERIAL AND METHODS: blue light treatment; Lutein, treatment with 25 μM lutein as a positive control; and three Hyperoside groups, treated with 37.5, 75, or 150 μM hyperoside. The antiapoptotic effect of hyperoside was evaluated using flow cytometry and TUNEL assays, and the intrinsic apoptotic pathway proteins (Bcl-xL, Bad, and Bim) were analyzed via western blotting. The interactions of hyperoside with JNK and p38 MAPKs were determined using western blotting, and molecular docking. The antioxidative effect of hyperoside was measured via DPPH and ABTS radical scavenging assays; Nrf2/HO-1 activation and SOD-1 stimulation were analyzed using western blotting and immunofluorescence assay. The anticarbonyl effect (4-HNE and MDA) was measured using western blotting. RESULTS: Hyperoside was nontoxic to ARPE-19 cells up to 150 μM. It dose-dependently decreased A2E and blue light-induced AMD in ARPE-19 cells by upregulating the antiapoptotic Bcl-2 protein (Bcl-xL) and downregulating the proapoptotic Bcl-2 proteins (Bad and Bim). Hyperoside dephosphorylated JNK and p38 MAPKs in a dose-dependent manner, eradicated DPPH and ABTS radicals, and activated Nrf2/HO-1 and SOD-1. It also decreased the levels of 4-HNE and MDA. CONCLUSION: We conclude that C. japonica hyperoside could be a promising anti-AMD drug.