Silencing of circular RNA‑ZYG11B exerts a neuroprotective effect against retinal neurodegeneration

Ischemic retinal diseases are the major cause of vision impairment worldwide. Currently, there are no available treatments for ischemia-induced retinal neurodegeneration. Circular RNAs (circRNAs) have emerged as important regulators of several biological processes and human diseases. The present study investigated the role of circRNA-ZYG11B (circ-ZYG11B; hsa_circ_0003739) in retinal neurodegeneration. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) demonstrated that circZYG11B expression was markedly increased during retinal neurodegeneration in vivo and in vitro. Cell Counting Kit-8, TUNEL and caspase-3 activity assays revealed that silencing of circZYG11B was able to protect against oxidative stress-or hypoxic stress-induced retinal ganglion cell (RGC) injury. Furthermore, immunofluorescence staining and hematoxylin and eosin staining revealed that silencing of circZYG11B alleviated ischemia/reperfusion-induced retinal neurodegeneration, as indicated by reduced RGC injury and decreased retinal reactive gliosis. In addition, luciferase reporter, biotin-coupled miRNA capture and RNA immunoprecipitation assays revealed that circZYG11B could regulate RGC function through circZYG11B/microRNA-620/PTEN signaling. Clinically, RT-qPCR assays demonstrated that circZYG11B expression was markedly increased in the aqueous humor of patients with glaucoma. In conclusion, circZYG11B may be considered a promising target for the diagnosis and treatment of retinal ischemic diseases. Key words: retinal ischemia, ischemia/reperfusion, circular RNA, retinal neurodegeneration