TRIM46 contributes to high glucose-induced ferroptosis and cell growth inhibition in human retinal capillary endothelial cells by facilitating GPX4 ubiquitination

作者：Jingfa Zhang, Qinghua Qiu, Haiyan Wang, Chong Chen, Dawei Luo · 发表于：Experimental Cell Research · 年份：2021 · DOI：10.1016/j.yexcr.2021.112800 · 被引用次数：146 · 研究领域：Ferroptosis and cancer prognosis、Retinal Diseases and Treatments、interferon and immune responses

PURPOSE: Increased permeability of retinal capillary endothelial cells is a key feature in the progression of diabetic retinopathy (DR). Precisely why and how diabetes causes dysfunction in retinal capillary endothelial cells is not well understood, making it challenging to explore more advanced therapeutics. METHODS: Cell proliferation was assessed by the Cell Counting Kit-8 assay. Ferroptosis was evaluated by measuring lipid reactive oxygen species levels by flow cytometry and determining malondialdehyde, superoxide dismutase, and glutathione peroxidase levels through biochemical assays. Western blot analysis and quantitative PCR were respectively used to check the expression of proteins and RNAs. Co-immunoprecipitation assays were used to confirm the interaction between TRIM46 and GPX4. RESULTS: High glucose (HG, 25 mM glucose) significantly suppressed cell growth, which could be reversed by the ferroptosis inhibitor, ferrostatin-1. HG treatment time-dependently induced ferroptosis in human retinal capillary endothelial cells (HRCECs) and induced TRIM46 expression. Lentiviral-mediated overexpression of TRIM46 decreased cell resistance against HG-induced ferroptosis, whereas knockdown showed the opposite effect. Administration of RSL3, a ferroptosis agonist, was able to reverse the protective effects of TRIM46 silencing. TRIM46 interacted with GPX4, an important enzyme that suppresses ferroptosis, and promoted GPX4 ubiquitination. Furthermore, lentiviral-mediated overexpres...