Protection And Mechanism Of ROCK Inhibitor Y-27632against Oxidative Stress In Corneal Epithelium

Purpose. We recently reported that Y-27632, a member of the ROCK inhibitorfamily, has increased the cloning efficiency of rabbit limbal stem/progenitor cells byimproving their adherence and ROS scavenging. Here we investigated the protectionand mechanisms of Y-27632against H₂O₂-induced oxidative stress by using mousecornea and mouse corneal stem/progenitor cells （TKE2）.Methods. In vitro and in vivo oxidative stress models were established byhydrogen peroxide （H₂O₂） treatment in cultured TKE2cells and mouse cornea. Cellmorphology and proliferation capacity were conducted to measure the effects ofY-27632on cell viability. Cellular oxidant-antioxidant balance was examined by ROSstaining and NOX4fluorescence staining. The activity of NRF2-ARE signalingpathway was measured by immunostaining and quantitative Real time-PCR.Results. Y-27632protected the mouse TKE2cells and mouse cornea fromH₂O₂-induced oxidative stress. The main mechanisms included:（1） Y-27632prevented the up-regulation of NOX4and decreased the ROS accumulation inducedby H₂O₂treatment.（2） Y-27632prevented the overexpression of NRF2signalpathway and the downstream genes including NAD（P）H quinone oxidoreductase andglutathione S-transferase induced by H₂O₂.Conclusions. Y-27632alleviated the oxidative stress in corneal epithelium invitro and in vivo by preventing the overexpression of NOX4and NRF2.