Ferrostatin-1 alleviates tissue and cell damage in diabetic retinopathy by improving the antioxidant capacity of the Xc(-)-GPX4 system

Diabetic retinopathy (DR) is a common microvascular complication leading to a high blindness rate among patients with diabetes. Ferroptosis is a type of cell death caused by the accumulation of iron-dependent lipid peroxides. Studies have shown that ferroptosis plays an important role in DR. The rat model of DR was constructed and treated with Ferrostatin-1 (Ferr-1). Haematoxylin and eosin (HE) were used to detect the degree of retinopathy. Oxidative stress levels were detected by ELISA. Perl’s staining was used to detect iron deposition in retinal tissues. Ferritin levels were measured by ELISA. The expression of GPX4 was detected by immunohistochemistry (IHC). GSH/GSSG kit was used to detect the content and proportion of reduced/oxidized glutathione. Western blot was used to detect the expression of ferroptosis-related proteins. TUNEL assay was used to detect cell apoptosis. The expression of GSDMD was detected by fluorescence in situ hybridization (FISH). Western blot was used to detect the expression of apoptosis and pyroptosis-related proteins. Then, high glucose (HG)-induced retinal epithelial cell line ARPE-19 was treated by Erastin (ferroptosis activator) and Ferr-1. CCK-8, ELISA, western blot, flow cytometry, and immunofluorescence (IF) staining were used to detect oxidative stress levels, ferroptosis and cell damage. The mechanism was further explored by adding ferroptosis agonist Erastin. In vitro and in vivo results showed that oxidative stress was increased in DR model, resulting in ferroptosis and tissue or cell damage. After administration of Ferr-1, the antioxidant capacity was improved, ferroptosis levels were reduced and tissue or cell damage was alleviated. In vitro results showed that Ferr-1 reversed the impacts of Erastin on oxidative stress, ferroptosis, and cell damage in HG-induced ARPE-19 cells. Ferr-1 alleviated tissue and cell damage by improving the antioxidant capacity of the Xc(-)-GPX4 system.