Cytoprotective Effect of Rho Kinase Inhibitors against Oxidative Stress inTrabecular Meshwork Cells

ABSTRACT

Purpose@#We evaluated the protective effect of trabecular outflow drugs, Rho kinase (ROCK) inhibitors against oxidative stressin trabecular meshwork cells. @*Methods@#Primary-cultured human trabecular meshwork cells (HTMCs) were exposed to ROCK inhibitors at 10 and 20 μMY-27632, ripasudil or fasudil for 24 hours, after pretreatment with 200 μM hydrogen peroxide for 30 min. The cell viabilities andmetabolic activities were assessed using the Trypan Blue dye exclusion test and MTT assay, respectively. Reactive oxygen species(ROS) production was measured using the H2DCFDA assay, and the degree of apoptosis was measured with flow cytometryusing annexin-propidium iodide double staining. @*Results@#In HTMCs, Y-27632 suppressed ROS production. Ripasudil and fasudil increased the metabolic activities and decreasedthe degrees of apoptosis. Fasudil showed the most cytoprotective effects among the three ROCK inhibitors tested. @*Conclusions@#Against oxidative stress, ROCK inhibitors decreased apoptosis accompanied by decreased ROS production, especiallyfasudil. ROCK inhibitors may therefore have cytoprotective properties in addition to increasing trabecular outflow.