MicroRNAs as biomarkers of coronavirus disease 2019 (COVID-19): a scoping review

Abstract Background. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus which was identified as the infectious agent responsible for coronavirus disease 2019 (COVID-19). MicroRNAs (miRNAs) are small non-coding RNAs that can be potential biomarkers of several diseases. The aim of this scoping review was to identify which miRNAs could be biomarkers of COVID-19 and their roles. Methods. A literature search was performed based on PubMed, PubMed Central, BVS/BIREME, Web of Science, Scopus, EBSCOhost, ProQuest, Embase, and Cochrane Library for studies published until January 28th, 2021. Animal and human studies that described miRNAs as biomarkers of SARS-CoV-2 infection/COVID-19 were included. Studies with a purely computational approach were excluded. Results. A total of 1,797 records were identified, seven of which met the eligibility criteria. Six studies were conducted in humans (samples derived from blood) and one was performed in an animal model (lung tissue). The most important miRNAs identified were miR-195-5p, miR-618, miR-146a-5p, miR-21-5p, miR-15b-5p, miR-142-3p, miR-155, miR-208a, miR-499, miR-103a-2-5p, miR-200c-3p, miR-2115-3p, and members of the let-7 family. Among these miRNAs, miR-146a-5p, miR-21-5p, miR-15b-5p, and members of the let-7 family may be important as they were deregulated in more than one study. Dysregulated miRNAs appear to play key roles in viral replication, proliferation of infected cells, immune response, inflammation, or cardiovascular dysfunction. Conclusion. MiRNAs may be used as potential diagnostic or severity biomarkers, predictive biomarkers, biomarkers of T-cell immune response, and as therapeutic targets of COVID-19. Further studies are required to investigate and validate the role of miRNAs as biomarkers of COVID-19.