Upregulation of EphA2 is associated with apoptosis in response to H2O2 and UV radiation-induced cataracts.

ABSTRACT

In this article, we examine the role of erythropoietin-producing hepatocellular receptor A2 (EphA2) in the apoptosis of lens epithelial cells (LECs) in H2O2 and UV radiation-induced cataracts. We treated SRA01/04 cells with H2O2 or ultraviolet (UV) radiation to create a cataract cell model. We constructed a cataract lens model by exposing mice to UV radiation. We used CCK8 assays, Annexin V-FITC analysis, and immunohistochemical staining to explore proliferation and apoptosis of the cataract model. Thereafter, we used quantitative real-time PCR (qPCR) analysis, Western blot assays, and immunofluorescence to determine gene and protein expression levels. We also employed Crispr/Cas9 gene editing to create an EphA2 knockout in SRA01/04 cells. Results: H2O2 or UV radiation induced SRA01/04 cells showed EphA2 gene upregulation. CCK8 and apoptosis assays showed that EphA2 over-expression (OE) reduced epithelial cell apoptosis, but knockout of EphA2 induced it in response to H2O2 and UV radiation, respectively. Mutation of the EphA2 protein kinase domain (c.2003G > A, p. G668D) had a limited effect on cell apoptosis. In vivo, the EphA2 protein level increased in the lenses of UV-treated mice. Our results showed that EphA2 was upregulated in SRA01/04 cells in response to H2O2 and UV radiation. Mutation of the EphA2 protein kinase domain (c.2003G > A, p. G668D) had a limited effect on H2O2 and UV radiation-induced cell apoptosis. We confirmed this change with an experiment on UV-treated mice. The present study established a novel association between EphA2 and LEC apoptosis.