Electroconvulsive stimulation alters levels of BDNF-associated microRNAs

Electroconvulsive therapy (ECT) is the most effective antidepressant treatment available yet its mechanism of action remains incompletely understood. Electroconvulsive stimulation (ECS), a rat model of electroconvulsive therapy, induces expression of brain derived neurotrophic factor (BDNF) within the brain but the precise means by which this occurs and by which it contributes to the antidepressant effects of ECS are unknown. MicroRNAs (miRNAs), a class of endogenous small non-coding RNA species, may play a role as BDNF can both regulate and be regulated by miRNAs. We examined expression of BDNF-associated miRNAs in rat brain and blood following either acute (x1) or chronic (x10) ECS. Fourteen BDNF-associated miRNA species were identified for investigation using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). We found that levels of miRNA miR-212 were significantly increased in rat dentate gyrus following both acute and chronic ECS. MiR-212 levels also increased in whole blood following chronic ECS and this positively correlated with miR-212 levels in the dentate gyrus. Our results suggest that alterations in miRNA expression may be informative about the mechanism of action of ECS/ECT.