Circulating miRNAs are Down-regulated in Asthmatic Patients; Case-control Study

<b>Purpose:</b> Microribonucleic acids (miRNAs) play an important role as non-invasive biomarkers and predictors of inflammatory disease activity. This study aimed to determine differences in expression profiles of miRNAs in patients with asthma compared to healthy controls (HC). <b>Study Design and Methods:</b> In this study, we evaluated a panel of 84 miRNAs in plasma from 3 asthmatic patients and three healthy controls (HC), and we observed decreased levels of miR-17-5p, miR-18a-5p, miR-106b-5p, miR-126-3p, miR-223-3p y miR-374a-5p which were validated in an independent group. Real-time PCR was performed to compare the expression level of each miRNA in a group of 27 asthmatic patients and 27 healthy controls. <b>Results:</b> Correlations between miRNAs and body mass index (BMI) and forced expiratory volume during the first second (FEV1) were also determined. Asthmatic patients had lower levels of miR-17-5p(p=0.026), miR-106-5p (p=0.022), miR-126-3p (p=0.041, and miR-223-3p (p=0.13) than healthy controls. miRNAs did not correlate with BMI and FEV₁. <b>Conclusion:</b> Data suggest that circulating miRNAs described in this study could be employed as biomarkers for asthma prediction.