Study on the Mechanism of miR-143 in the Activation of Astrocytes Induced by Oxygen-glucose Deprivation/Reperfusion

OBJECTIVE To explore the effect of miR-143/HIPK2 axis on the astrocyte activation induced by oxygen-glucose deprivation/reperfusion(OGD/R). METHODS The expression of GFAP, an astrocyte specific activation marker, and HIPK2 protein kinase were detected by Western blotting, and the level of miR-143 was detected by real time PCR in astrocyte with OGD/R treatment for 0, 3, 6, 12 h. GFAP expression detected by immunofluorescence staining after OGD/R treatment for 6 h. The control group was transfected with Anti-Con and Anti-miR-143, also the OGD/R model group was transfected with Anti-Con and Anti-miR-143. The expression of GFAP was detected by Western blotting. The method of luciferase reporter gene was used to verify whether HIPK2 was the target of miR-143. Astrocytes were transfected with miR-143/miR-Con and Anti-miR-143/Anti-miR-Con followed by HIPK2 examination using Western blotting. Astrocytes cultured in vitro were divided into five treatment groups:control group with Anti-Con intervention, OGD/R model group with Anti-Con intervention, OGD/R model group with Anti-miR-143 intervention, OGD/R model group with Anti-miR-143 and siRNA Con cointervention, and OGD/R model group with Anti-miR-143 and HIPK2 siRNA cointervention. GFAP expression was detected by Western blotting. RESULTS Compared with the control group, GFAP expression in astrocytes increased to the peak value(P<0.01), confirmed by immunofluorescent staining HIPK2 expression decreased to the lowest value (P<0.001), the expression of miR-143 in astrocytes increased after OGD/R 6 h treatment(P<0.01). Compared with control group with Anti-Con intervention, GFAP expression in OGD/R group with Anti-Con intervention was upregulated(P<0.01). Compared with OGD/R group with Anti-Con intervention, GFAP expression was downregulated in OGD/R group with Anti-miR-143 intervention(P<0.05). miR-143 significantly inhibited HIPK2 gene activity, but had no significant inhibitory effect on its binding site mutants. Compared with OGD/R group with Anti-miR-143 and siRNA Con cointervention, GFAP expression level in astrocytes in OGD/R group with Anti-miR-143 and HIPK2 siRNA cointervention was upregulated(P<0.05). CONCLUSION OGD/R induces activation of astrocytes through miR-143/HIPK2 axis.