The LncRNA H19 Binding to Let-7b Promotes Hippocampal Glial Cell Activation and Epileptic Seizures by Targeting Stat3 in a Rat Model of Temporal Lobe Epilepsy

Objectives: Glial cell activation contributes to the inflammatory response and occurrence of epilepsy. Our preliminary study demonstrated that the long non-coding RNA, H19, promotes hippocampal glial cell activation during epileptogenesis. However, the precise mechanisms underlying this effect remain unclear.

Materials And Methods: H19 and let-7b were overexpressed or silenced using an adeno-associated viral vector in vivo. Their expression in a kainic acid-induced epilepsy model was evaluated by real-time quantitative PCR, fluorescence in situ hybridization, and cytoplasmic and nuclear RNA isolation. A dual-luciferase reporter assay was used to evaluate the direct binding of let-7b to its target genes and H19. Western blot, video camera monitoring and Morris water maze were performed to confirm the role of H19 and let7b on epileptogenesis.

Results: H19 was increased in rat hippocampus neurons after status epilepticus, which might be due to epileptic seizure-induced hypoxia. Increased H19 aggravated the epileptic seizures, memory impairment and mossy fibre sprouting of the epileptic rats. H19 could competitively bind to let-7b to suppress its expression. Overexpression of let-7b inhibited hippocampal glial cell activation, inflammatory response and epileptic seizures by targeting Stat3. Moreover, overexpressed H19 reversed the inhibitory effect of let-7b on glial cell activation.

Conclusions: LncRNA H19 could competitively bind to let-7b to promote hippocampal glial cell activation and epileptic seizures by targeting Stat3 in a rat model of temporal lobe epilepsy.