MicroRNA and epilepsy: profiling, functions and potential clinical applications

Purpose of reviewThis review provides a synthesis of recent profiling studies investigating microRNA (miRNA) changes in experimental and human epilepsy, and outlines mechanistic, therapeutic and diagnostic potentials of this research area for clinical practice.Recent findingsA series of studies in experimental and human epilepsy have undertaken large-scale expression profiling of miRNAs, key regulatory molecules in cells controlling protein levels. Levels of over 100 different miRNAs were found to either increase or decrease in the hippocampus, of which more than 20 were identified in more than one study, including higher levels of miR-23a, miR-34a, miR-132 and miR-146a. Altered levels of enzymes involved in miRNA biogenesis and function, including Dicer and Argonaute 2, have also been found in epileptic brain tissue. Functional studies using oligonucleotide-based inhibitors support roles for miRNAs in the control of cell death, synaptic structure, inflammation and the immune response. Finally, data show brain injuries that precipitate epilepsy generate unique miRNA profiles in biofluids.SummarymiRNA represents a potentially important mechanism controlling protein levels in epilepsy. As such, miRNAs might be targeted to prevent or disrupt epilepsy as well as serve as diagnostic biomarkers of epileptogenesis.