Identification and functional analysis of circular RNAs induced in rats by middle cerebral artery occlusion

CircRNAs (Circular RNAs) are believed to be involved in a multitude of biological processes and can play crucial roles as miRNA (microRNA) sponges. The aim of this study was to explore the relationship between circRNAs and ischemic stroke induced by middle cerebral artery occlusion (MCAO) in rats. The expression profiles of circRNAs in brain tissues were screened by high-throughput sequencing (HTS) to identify novel differentially expressed circRNAs (DECs). Quantitative real-time (qRT)-PCR was used to confirm circRNA expression data arising from HTS. In addition, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to investigate mRNA function and to understand the characteristics of circRNAs. Finally, we created a circRNA-miRNA network. In total, 14,694 DECs, from 6 brain tissues, were screened; of these, 87 DECs showed a significant fold change >2 (p < 0.05). CircRNAs showing significant upregulation included circRNA.17737, circRNA.8828 and circRNA.14479, while circRNA.1059, circRNA.9967 and circRNA.6952 were significant downregulation. The results were in accordance with HTS, showing that the HTS produced reliable data. Herein, we explored the relationship between circRNAs and ischemic stroke induced by MCAO in rats. Our data provide a new and better understanding of the molecular mechanisms associated with ischemic stroke. The precise role of DECs associated with MCAO and target miRNAs should be validated in further studies.