EN
INTRODUCTION: Epilepsy frequently develops as a result of brain insult, for example: brain injury, status epilepticus, or stroke, however currently there are no tools allowing us to predict which patients suffering from trauma will eventually develop epilepsy or how severe it is going to be. In recent years small non-coding RNAs are proposed as biomarkers for neurological diseases. Particularly microRNAs are interesting candidates, as several of them were described changing their levels in the brain of epileptic subjects. There is evidence suggesting that microRNAs levels are altered also in the plasma, making them attractive candidates for peripheral biomarkers of epilepsy. AIM(S): This study was conducted to evaluate usefulness of plasma miRNAs as biomarkers of epileptogenesis and epilepsy. METHOD(S): In our studies we used the rat model of temporal lobe epilepsy. The status epilepticus was evoked by the stimulation of left lateral nucleus of amygdala. Animals were continuously video and EEG monitored for 6 months. Blood was collected at 14, 30, 60, and 90 days after stimulation from tail vein. Blood plasma was separated and processed using Affymetrix miRNA 4.1 array strip microarrays. RESULTS: We have compared miRNA levels between sham operated (n=12) and stimulated animals (n=15); p<0.01 was used as a cut off. We have detected 14 miRNA differentiating between sham operated and stimulated animals at 14 days, 6 at 30 d, 16 at 60d, and 11 at 90 days. We have also compared the miRNAs levels between animals with high (30–70 seizures/day) and low (1–5 seizures/day) number of seizures. We found differences in levels of 11 miRNA at 14 d, 7 at 30 d, 11 at 60 d and 8 at 90 d (at p<0.01). CONCLUSIONS: Levels of miRNA in plasma are altered during epileptogenesis and differentiate between animals with frequent and rare seizures. miRNA may become a useful biomarker of epileptogenesis/epilepsy as well as severity of the disease. FINANCIAL SUPPORT: This work was supported by the FP7-HEALTH project 602102 (EPITARGET) and Polish Ministry of Science and Education grant W19/7.PR/2014.