ROS-mediated Different Homeostasis of Murine Corneal Epithelial Progenitor Cell Line under Oxidative Stress

The role of ROS in stem cell biology has not been fully illustrated and understood. Here we compared the different responses and investigated the mechanism underlying oxidative stress induced by hydrogen peroxide (H₂O₂) between murine corneal epithelial progenitor cell line (TKE2) and mature murine corneal epithelial cells (MCE). TKE2 showed a different homeostasis and strong resistance to H₂O₂. TKE2 reduced the production of ROS, inhibited ROS generation enzyme NADPH oxidase 4 (NOX4), and increased dual specificity phosphatase 6 (DUSP6). Furthermore, TKE2 activated nuclear factor (erythroid-derived 2)-like 2 (NRF2) signaling pathway, regulated miR-125B1 and miR-29B1, and elevated levels of antioxidants glutathione S-transferase P (GSTP) and superoxide dismutases (SOD). The association with ROS of the cells was also verified by RNA interference approach and pharmacological antagonization. In addition, TKE2 enhanced the autophagy after exposure to H₂O₂. The novel evidence suggests that TKE2 cells have different homeostasis and strong antioxidant properties against oxidative stress via the regulation of ROS formation and pathway.