Analysis of plasma miRNAs expression profile in different subtypes of ischemic stroke

Objective To investigate the changes of circulating miRNAs expression profiles in different subtypes of ischemic stroke according to the Trial of Org 10 172 in Acute Stroke Treatment. Methods We selected 16 patients diagnosed as acute ischemic stroke at first time in the Department of Neurology, the Affiliated Hospital of Medical College Qingdao University from November to December in 2012. They were divided into large artery atherosclerosis (LAA) stroke group (n=8) and small artery occlusive (SAO) stroke group (n=8). At the same time, 8 healthy checkup subjects were selected as control. High-throughput sequencing was used to detect the expression profiles of miRNAs in the plasma, and the high-throughput sequencing results were validated by quantitative real-time polymerase chain reaction. We performed the miRNAs variance analysis and associated bioinformatics analysis. Results Thirty hundred and sixty-nine miRNAs were detected in LAA group, SAO group and the control group. We found remarkable differences (fold change>2, P 2, P 2, P 2, P<0.01) in SAO group. The expression levels of miR-146b-5p, miR-23a-3p and miR-451a were validated in accordance with the results of real-time PCR. Target gene prediction and functional analysis revealed that target genes regulated by differential expression of miRNAs were mainly associated with cell proliferation, adhesion, metabolism and other biological functions. Conclusion miRNAs are differently expressed in the plasma of LAA group, SAO group and healthy control group, which suggest that miRNAs might play different roles in the pathogenesis of LAA stroke and SAO stroke by regulating downstream target genes. Key words: Brain ischemia; Stroke; microRNAs; High-throughput screening assays; Atherosclerosis