Alteration of micro-RNAs (miRNAs) expression, including miRNA-122a, -146a and -205 family members, can have profound effects on inflammatory and IFN pathways (miRNA-146a), known as hallmarks of COVID-19. SARS-CoV-2-infected patients were recruited at Policlinico Umberto I Hospital of Sapienza University of Rome (Italy). MiRNA-122a, -146a, -205 and IFI27 (Interferon Alpha Inducible Protein 27) levels were screened in SARS-CoV-2 patients (n = 14) and healthy controls (n = 10) by real-time RT-PCR assays. Then, miRNA-146a rs2910164 GC single-nucleotide polymorphism (SNP) was genotyped in a larger group of COVID-19 patients (n = 129), and its relationship with severe disease [Intensive Care Unit (ICU) support or survival/death] was assessed. SARS-CoV-2-positive patients had increased PCR, D-Dimer and Fibrinogen levels compared to healthy controls (p < .05 for all measurements). MiRNA-122a and -146a serum levels were upregulated in COVID-19 patients (miRNA-122a: p = .002; miRNA-146a: p < .001). Decreased IFI27 levels were observed in COVID-19 patients with higher miRNA-146a levels (p = .047). Moreover, miRNA-146a rs2910164 C/G genotypes distributions were similar in COVID-19 patients and in validated European healthy subjects (n = 37,214). MiRNA-146a SNP was not associated with severe COVID-19 outcome (ICU or death). MiRNA-122a and -146a levels were elevated in SARS-CoV-2 infected patients, with miRNA-146a upregulation possibly contributing to IFN pathways dysregulation (e.g., reduced IFI27 levels) observed in severe COVID-19, although there is no evidence for the involvement of rs2910164 SNP.
Keywords: COVID-19; IFI27; IFN response; ISG; SARS-CoV-2; inflammation; miRNA-122a; miRNA-146a and miRNA-205; miRNA-146a rs2910164 SNP.