The Expression Profiles and Role of Circular RNA in Peripheral Blood of Myocardial Infarction Patients

Abstract

Background: Myocardial infarction (MI) is one of the most widespread illnesses seriously harmful to human health. However, the mechanisms of its pathogenesis have not yet been completely proved. circRNA is one kind of non-coding RNA, recently published data suggests that circRNAs play a crucial role in heart diseases, but their expression profiles and role in MI patients are not yet completely defined. Methods: RNAs from peripheral blood samples were recruited for high-throughput RNA-seq analysis; The junction site part of circRNAs was confirmed by PCR with divergent primers; ROC curves were created to estimate the diagnostic value of circRNAs for MI; The expression level of circRNAs in clinical and cell samples were detected by RT-qPCR; MiRNA target site in exons of circRNA loci was verified by using miRanda, The binding sites of miRNA and mRNA were predicted by RNAhybrid; The regulatory roles of circSLC8A1 in cardiomyocytes were detected by TUNEL and Immunoblotting.Results: A total of 3862 circRNAs were detected to be remarkably changed, including 2738 circRNAs being upregulated, 1124 circRNAs being downregulated. circTMEM165, circUBAC2, circZNF609, circANKRD12, and circSLC8A1 were upregulated in MI and had closed loop structure. The results of ROC curves revealed that these five circRNAs had good sensitivity and specificity for MI diagnosis. Moreover, we created networks among circRNAs, miRNAs and mRNAs to predict the regulatory roles of circRNAs in MI. Besides that, we also demonstrated that circSLC8A1 contributed to cardiomyocytes apoptosis. Conclusions: In this study, we depicted the expression profiles of circular RNA in peripheral blood of myocardial infarction patients, revealed the five circRNAs may be very beneficial for MI diagnosis and regarded as possible biomarkers. Moreover, we also revealed that circSLC8A1 played a critical role in cardiomyocytes apoptosis.