Differential microRNAs expression in calcified versus rheumatic aortic valve disease

Background: The aortic valve (AV) is the most commonly affected valve in valvular heart diseases (VHDs). The objective of the study is to identify microRNA (miRNA) molecules expressed in VHDs and the differential expression patterns of miRNA in AVs with either calcification or rheumatism etiologies. Methods: Human AVs were collected during valve replacement surgery. RNA was extracted and miRNA containing libraries were prepared and sequenced using the next generation sequencing (NGS) approach. miRNAs identified as differentially expressed between the two etiologies were validated by quantitative real-time polymerase chain reaction (qPCR). The receiver operating characteristic (ROC) curve analysis was performed to examine the ability of relevant miRNA to differentiate between calcification and rheumatism etiologies. Results: Rheumatic and calcified AV samples were prepared for the NGS and were successfully sequenced. The expression was validated by the qPCR approach in 46 AVs, 13 rheumatic, and 33 calcified AVs, confirming that miR-145-5p, miR-199a-5p, and miR-5701 were significantly higher in rheumatic AVs as compared with calcified AVs. ROC curve analysis revealed that miR-145-5p had a sensitivity of 76.92% and a specificity of 94.12%, area under the curve (AUC) = 0.88 (P =.0001), and miR-5701 had a sensitivity of 84.62% and a specificity of 76.47%, AUC = 0.78 (P =.0001), whereas miR-199a-5p had a sensitivity of 84.62%, and a specificity of 57.58%, AUC = 0.73 (P =.0083). Conclusion: We documented differential miRNA expression between AV disease etiologies. The miRNAs identified in this study advance our understanding of the mechanisms underlining AV disease.