Ripasudil alleviated the inflammation of RPE cells by targeting the miR-136-5p/ROCK/NLRP3 pathway

Background Inflammation of RPE cells led to different kinds of eye diseases and affected the normal function of the retina. Furthermore, higher levels of ROCK1 and ROCK2 induced injury of endothelial cells and many inflammatory diseases of the eyes. Ripasudil, which was used for the treatment of glaucoma, was one kind of the inhibitor of ROCK1 and ROCK2, but whether ripasudil could relieve the LPS-induced inflammation and damage of RPE cells was not clear. Methods We used LPS to stimulate ARPE-19 cells, the RPE cell line. After that, we detected the levels of ROCK1 and ROCK2 by western-blotting after the stimulation of LPS and treatment of ripasudil. Then luciferase reporter assays were used to confirm the targeting effect of miR-136-5p on ROCK1 and ROCK2. At last, the levels of NLRP3, ASC, caspase1, IL-1 beta and IL-18 were detected with the western-blotting after the knockdown of miR-136-5p. Results The levels of ROCK1, ROCK2 and miR-136-5p in ARPE-19 cells were promoted after the stimulation of LPS. After the treatment of ripasudil, the expression levels of ROCK1, ROCK2 and miR-136-5p were suppressed. The expression of ROCK1 and ROCK2 was targeted and inhibited by the miR-136-5p. The levels of inflammation related proteins NLRP3, ASC, caspase1, IL-1 beta and IL-18 was also inhibited after the treatment of ripasudil. However, the expression of these proteins was rescued after the knockdown of miR-136-5p. Conclusion Ripasudil relieved the inflammatory injury of RPE cells by upregulating miR-136-5p, therefore inhibiting the expression of ROCK1, ROCK2, NLRP3, ASC, caspase1, IL-1 beta and IL-18.