Background: The regulatory potency of circular RNA (circRNA) has been acknowledged in multiple human diseases, including ischaemic stroke (IS). However, only a few circRNAs were investigated in this disorder. We aimed to uncover the role of circ_0001360 in cell models of IS in vitro.
Methods: SK-N-SH cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to simulate IS pathology conditions in vitro. Quantitative real-time PCR (qPCR) and western blot were applied for expression detection. Cell viability, proliferation and apoptosis were investigated by CCK-8, EdU and flow cytometry assays. The predicted binding of miR-671-5p to circ_0001360 or BMF 3'UTR was validated by dual-luciferase reporter and RIP assays. Proteins on the NF-κB pathway were quantified by western blot to assess NF-κB pathway activity.
Results: Circ_0001360 was upregulated in SK-N-SH cells after OGD/R treatment. OGD/R provoked SK-N-SH cell growth impairment, apoptosis and inflammation, while circ_0001360 knockdown relieved these injuries. Circ_0001360 targeted miR-671-5p, and miR-671-5p deficiency recovered SK-N-SH cell injury that was repressed by circ_0001360 knockdown. MiR-671-5p directly combined with BMF and repressed BMF expression. Accordingly, circ_0001360 targeted miR-671-5p to regulate the expression of BMF. Circ_0001360 knockdown weakened the phosphorylated levels of P65 and IκBα, while further miR-671-5p deficiency or BMF overexpression restored their expression levels.
Conclusion: Circ_0001360 contributed to OGD/R-caused SK-N-SH cell injury via targeting the miR-671-5p/BMF network and activating the NF-κB pathway, thus participating in the development of IS.
Keywords: BMF; Circ_0001360; OGD/R; SK-N-SH; ischaemic stroke; miR-671-5p.