Circ_0000011 promotes cerebral ischemia/reperfusion injury via miR-27a-3p-dependent regulation of NRIP1

Background: Cerebral ischemia/reperfusion (I/R) can result in brain function impairments. Circular RNAs (circRNAs) have emerged as vital regulators in cerebral I/R injury. However, the functions of mmu_circ_0000011 in cerebral I/R injury are still unclear. Thus, in this study, we aimed to explore the effect of mmu_circ_0000011 on cerebral I/R injury. Methods: Oxygen-glucose deprivation and reperfusion (OGD/R)-induced HT-22 cells were used to mimic the condition of cerebral I/R injury in vitro. Cell Counting Kit-8 (CCK-8) assay, lactate dehydrogenase (LDH) assay, 5’-ethynyl-2’-deoxyuridine (EdU) assay and flow cytometry analysis were utilized to assess cell viability, LDH release, proliferation and apoptosis, respectively. qRT-PCR and western blot were performed to determined the levels of circ_0000011, miR-27a-3p and NRIP1. Dual-luciferase reporter assay and RNA pull-down assay were utilized to analyze the targeting relation of circ_0000011, miR-27a-3p and NRIP1. Results: OGD/R treatment inhibited HT-22 cell viability and promoted LDH release, cell apoptosis and inflammation. Circ_0000011 level was increased in OGD/R-induced HT-22 cells. Silencing of circ_0000011 promoted cell proliferation and inhibited LDH release, apoptosis and inflammation in OGD/R-treated HT-22 cells. For mechanism analysis, circ_0000011 was demonstrated to sponge miR-27a-3p, which directly targeted NRIP1. MiR-27a-3p inhibition or NRIP1 overexpression ameliorated the impacts of circ_0000011 silencing on cell proliferation, LDH release, apoptosis and inflammation in OGD/R-treated HT-22 cells. Conclusions: Circ_0000011 promotes OGD/R-induced HT-22 cell impairments by elevating NRIP1 through sponging miR-27a-3p.