Anti-epileptic effect of 2-deoxy-D-glucose by activation of miR-194/KATP signaling pathway.

Abstract

Epilepsy is a syndrome of central nervous system dysfunction caused by many reasons, which is mainly characterized by abnormal discharge of neurons in the brain. Therefore, finding new targets for epilepsy therapy has always been the focus and hotspot in neurological research field. Studies have found that 2-deoxy-D-glucose (2-DG) exerts anti-epileptic effect by up-regulation of KATP channel subunit Kir6.1, Kir6.2 mRNA and protein. By using the database of TargetScan and miRBase to perform complementary pairing analysis on the sequences of miRNA and related target genes, it predicted that miR-194 might be the upstream signaling molecule of KATP channel. This study aims to explore the mechanism by which 2-DG exerts its anti-epileptic effect by regulating KATP channel subunits Kir6.1 and Kir6.2 via miR-194. A magnesium-free epilepsy model was established and randomly divided into a control group, an epilepsy group (EP group), an EP+2-DG group, and miR-194 groups (including EP+miR-194 mimic, EP+miR-194 mimic+2-DG, EP+miR-194 mimic control, EP+miR-194 inhibitor, EP+miR-194 inhibitor+2-DG, and EP+miR-194 inhibitor control groups). The 2-DG was used to intervene miR-194 mimics, patch-clamp method was used to detect the spontaneous recurrent epileptiform discharges, real-time PCR was used to detect neuronal miR-194, Kir6.1, and Kir6.2 expressions, and the protein levels of Kir6.1 and Kir6.2were detected by Western blotting. Compared with the control group, there was no significant difference in the amplitude of spontaneous discharge potential in the EP group (P>0.05), but the frequency of spontaneous discharge was increased (P<0.05). Compared with the EP group, the frequency of spontaneous discharge was decreased (P<0.05). Compared with the EP+miR-194 mimic control group, the mRNA and protein expressions of Kir6.1 and Kir6.2 in the EP+miR-194 mimic group were down-regulated (all P<0.05). Compared with the EP+miR-194 inhibitor control group, the mRNA and protein expressions of Kir6.1 and Kir6.2 in the EP+miR-194 inhibitor group were up-regulated (all P<0.05). After pretreatment with miR-194 mimics, the mRNA and protein expression levels of KATP channel subunits Kir6.1 and Kir6.2 were decreased (all P<0.05). Compared with the EP+2-DG group, the mRNA and protein expression levels of Kir6.1 and Kir6.2 in the EP+miR-194 mimic+2-DG group were down-regulated (all P<0.05) and the mRNA and protein expression levels of Kir6.1 and Kir6.2 in the EP+miR-194 inhibitor+2-DG group were up-regulated (all P<0.05). The 2-DG might play an anti-epilepsy effect by up-regulating KATP channel subunits Kir6.1 and Kir6.2via miR-194.