Downregulation of circAsxl2 Relieves Neuronal Injury Induced by oxygen-glucose deprivation/reperfusion.

Abstract

Circular RNAs (circRNAs) have been shown to play an important role in cerebral ischemia-reperfusion (I/R) injury. However, the role of circAsxl2 (mmu_circ_0000346) in cerebral I/R injury remains unclear. Mouse brain neuronal cell line (HT-22) was used to perform oxygen-glucose deprivation/reperfusion (OGD/R) treatment. The levels of circAsxl2, microRNA (miR)-130b-5p and forkhead box O3 (FOXO3) were determined using quantitative real-time PCR. Cell viability and apoptosis were measured using cell counting kit 8 assay and flow cytometry. Commercial kits were used to assess cell cytotoxicity, inflammation and oxidative stress. Protein expression was analyzed by western blot. RNA interaction was verified using dual-luciferase reporter assay, RIP assay and RNA pull-down assay. CircAsxl2 was highly expressed in OGD/R-induced HT-22 cells, and its silencing could alleviate OGD/R-induced apoptosis, inflammation and oxidative stress in HT-22 cells. MiR-130b-5p was sponged by circAsxl2, and its inhibitor could overturn the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury. FOXO3 was targeted by miR-130b-5p and its expression was positively regulated by circAsxl2. In addition, the regulation of circAsxl2 knockdown on OGD/R-induced neuronal injury also was reversed by FOXO3 overexpression. CircAsxl2/miR-130b-5p/FOXO3 axis accelerated OGD/R-induced neuronal injury, which might provide effective strategies for treating cerebral I/R injury.