Acteoside alleviates high glucose-induced ROS accumulation and ferroptosis in ARPE-19 cells by activating the NRF2 signaling pathway.

OBJECTIVE: The role of Acteoside (ACT) in regulating ferroptosis of retinal pigment epithelial (RPE) cells in diabetic retinopathy (DR) through the NRF2 pathway was investigated. METHODS: An in vitro DR model was constructed by inducing ARPE-19 cells with 33 mmol/L high glucose (HG), and a C57BL/6 mouse DR model was established via intraperitoneal injection of STZ and treated with different doses of ACT. Ferroptosis was assessed using CCK-8 assay, kits, BODIPY-C11 staining, and Western blot. NRF2 nuclear translocation was examined by immunofluorescence. Retinal damage was evaluated by HE staining. RESULTS: Compared to the NG group, the HG group showed significantly reduced ARPE-19 cell viability, increased intracellular Fe2+ levels and lipid peroxidation, decreased GSH content, and downregulated expression of GPX4 and SLC7A11. Ferroptosis inhibitors Fer-1 and DFO significantly ameliorated HG-induced reductions in cell viability and increases in lipid peroxidation. Further ACT intervention markedly reversed the HG-induced promotion of ferroptosis. Additionally, ACT significantly promoted NRF2 nuclear translocation, and silencing NRF2 weakened ACT's inhibitory effect on ferroptosis. In animal experiments, mice in ACT intervention groups exhibited significantly alleviated retinal tissue damage, reduced tissue Fe2+, 4-HNE, and MDA levels, increased GSH content, and upregulated expression of NRF2, GPX4, and SLC7A11 proteins, with a dose-dependent trend. CONCLUSION: ACT alleviated HG-induced ROS accumulation and ferroptosis in ARPE-19 cells by activating the NRF2 pathway, and ACT upregulated NRF2 and inhibited ferroptosis in the retina of DR mice, thereby ameliorating retinal injury.