Circulating microRNAs as Biomarkers of Various Forms of Epilepsy

Epilepsy is a group of disorders characterized by a cluster of clinical and EEG signs leading to the formation of abnormal synchronous excitation of neurons in the brain. Epilepsy is one of the most common neurological disorders worldwide. Epilepsy is characterized by aberrant expression patterns, both at the level of matrix transcripts and at the level of regulatory RNA sequences. Aberrant expression of a number of microRNAs can mark a particular epileptic syndrome, which will improve the quality of differential diagnosis. In this work, the expression profile of six microRNAs was analyzed: hsa-miR-106b-5p, hsa-miR-134-5p, hsa-miR-122-5p, hsa-miR-132-3p, hsa-miR-155-5p, hsa-miR-206-5p in the blood plasma of patients suffering from temporal lobe epilepsy TLE (n=52), juvenile myoclonic epilepsy JME (n=42) in comparison with healthy volunteers. The expression analysis was carried out using RT-PCR, mathematical processing of the data was carried out according to the Livak method. A statistically significant change in the expression of hsa-miR-106b-5p, hsa-miR-134-5p, hsa-miR-122-5p, hsa-miR-132-3p was found. An increase in the expression of hsa-miR-134-5p and hsa-miR-122-5p was registered in the group of patients with TLE compared to the control, as well as an increase in the expression of hsa-miR-132-3p and hsa-miR-106b-5p in the JME group compared to the control. hsa-miR-122-5p, 106b-5p, 132-3p are also able to discriminate TLE from JME. Additionally, a number of microRNAs are able to discriminate patients with drug-resistant and drug-sensitive forms of epilepsy from the control, as well as patients with hippocampal sclerosis and patients without hippocampal sclerosis from the control. Our data allow us to propose these microRNAs as plasma biomarkers of various epileptic syndromes.