Recent players in the field of acute myocardial infarction biomarkers: Circulating cell-free DNA or microRNAs?

摘要

We read with great interest the letter recently published by Bliks0en et al. in the International Journal of Cardiology, where the authors reported for the first time that a significant increase of circulating mitochondrial DNA (mitDNA) has been observed after acute myocardial infarction (AMI) both in human and mice [1]. This is an indication for novel cardiac biomarker and therapeutic target for AMI. In fact, increased plasma cell-free DNA (cf-DNA) after AMI has also been demonstrated in several other studies [2-4], And we think that circulating mitDNA could be part of plasma cf-DNA, which includes both mitDNA and nuclear DNA. Meanwhile, circulating cardiac microRNAs (miRNAs) have also been found to be consistently elevated in the early stages of AMI and proposed to be the promising biomarkers for AMI [5,6]. Since circulating cf-DNA and miRNAs are all nucleotide-based biomarkers, comparisons shown in the currently available studies may help to provide some insights on the advantages and disadvantages of them. Here we compare them in several aspects for the diagnosis and prognosis of AMI, such as release kinetics into the blood, area under curve (AUC), specificity, sensitivity, and detection method, with the gold standard, cardiac troponin T (cTnT) and troponin I (cTnI), and attempt to predict the underline mechanisms related to the prognosis and complications of AMI.