LncRNA FGD5-AS1 acts as a competing endogenous RNA for miRNA-223 to lessen oxygen-glucose deprivation and simulated reperfusion (OGD/R)-induced neurons injury

The purpose of this study was to evaluate whether FGD5-AS1 participates in oxygen-glucose deprivation and simulated reperfusion (OGD/R)-induced neurons injury and the detailed mechanism. An OGD/R model was established using the primary cortical neuron isolated from the brains of Sprague-Dawley rats. qRT-PCR and western blot were performed to de-tect the RNA and protein expression levels, respectively. Cell counting kit 8 (CCK8) and flow cytometry assays were used to evaluate the proliferation and apoptosis of neurons. The luciferase reporter assay was used to verify the interaction between lncRNA FGD5-AS1 and miRNA-223. We found that the expression of FGD5-AS1 is decreased in neurons suffering from OGD/R. Up-regulation of FGD5-AS1 could recover proliferation and inhibit apoptosis of OGD/R-injured neurons. In addition, the interaction between FGD5-AS1 and miRNA-223 were verified. The expression of miRNA-223 was negatively correlated with the level of FGD5-AS1. In turn, the expression of insulin-like growth factor-1 receptor (IGFIR, a target gene of miR-223) was positively associated with the level of FGD5-AS1. Simultaneously down-regulating miR-223 and over-expressing FGD5-AS1 as well as IGF1R exhibited an additional effect of extenuating OGD/R damage i.e. increasing neuron proliferation and reducing neuron apoptosis. In conclusion, our findings indicated that FGD5-AS1 may protect the neuron against OGD/R injury via acting as a ceRNA for miR-223 to mediate IGF1R expression, which contributes to a deeper understanding of ischemic stroke and provide a promising therapeutic target for this disease.