Recent studies indicate that circular ribonucleic acids (circRNAs) are involved in a variety of human diseases. The roles of circRNAs in traumatic spinal cord injury (SCI) remain unknown, however. We performed RNA-seq to analyze the circRNA expression profile in rat spinal cord after SCI and to investigate the relevant mechanisms. In all, 150 circRNAs were significantly differentially expressed in rat spinal cord after SCI by a fold-change ≥2 and p value ≤0.05. Among these, 99 circRNAs were upregulated, while 51 were downregulated. Gene ontology, Kyoto Encyclopedia of Genes and Genomes pathway analyses, and circRNA/miocroRNA (miRNA) interaction networks were conducted to predict the potential roles of circRNAs in the process of SCI. In addition, the expression levels of six selected circRNAs were verified successfully by quantitative real-time polymerase chain reaction. Further study identified circRNA_07079 and circRNA_01282 as being associated with SCI, and they may participate in the pathophysiology of SCI through circRNA-targeted miRNA-messenger RNA axis. In summary, the results of our study revealed the expression profiles and potential functions of differentially expressed circRNAs in traumatic SCI in rats; this may provide new clues for studying the mechanisms underlying SCI and also present novel molecular targets for clinical therapy of SCI.
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