RESUMO
The degeneration of retinal pigment epithelium (RPE) cells in the sub retinal pigment epithelial space and choroid is an initial pathological characteristic for the age-related macular degeneration which is the leading cause of severe vision loss in old people. Moreover, oxidative stress is implicated as a major inducer of RPE cell death. Here, we assessed the correlation between the H2O2-induced RPE cell death and glutamine metabolism. We found under low glutamine supply (20 %), the ARPE-19 cells were more susceptive to H2O2-induced apoptosis. Moreover, the glutamine uptake and the glutaminase (GLS) were suppressed by H2O2 treatments. Moreover, we observed miR-23a was upregulated by H2O2 treatments and overexpression of miR-23a significantly sensitized ARPE-19 cells to H2O2. Importantly, Western blotting and luciferase assay demonstrated GLS1 is a direct target of miR-23a in RPE cells. Inhibition of the H2O2-induced miR-23a by antagomiR protected the RPE cells from the oxidative stress-induced cell death. In addition, recovery of GLS1 expression in miR-23a overexpressed RPE cells rescued the H2O2-induced cell death. This study illustrated a mechanism for the protection of the oxidative-induced RPE cell death through the recovery of glutamine metabolism by inhibition of miR-23a, contributing to the discovery of novel targets and the developments of therapeutic strategies for the prevention of RPE cells from oxidative stress.