DOES MICRORNAS IN SALIVARY EXOSOME REFLECT THE STATE OF COVID-19 INFECTION? (REVIEW ARTICLE)

Abstract

MicroRNA (miRNA) is a single-stranded RNA that can be found in various biological samples, including saliva. These molecules regulate gene expression at the posttranscriptional level. In recent years, miRNAs have been studied as biological markers to help establish the disease's diagnosis, severity, and prognosis. The miRNA molecule has prognostic potential to identify severe vs. light and identify asymptomatic infections problematic in the spread of epidemics or COVID-19 pandemic. It has been reported that Angiotensin-Converting Enzyme 2 (ACE-2) is the primary receptor expressed on the host cell for SARS-CoV-2. ACE-2 molecule plays an essential role in the entry of SARS-CoV-2 into cells to subsequently cause late infection (COVID-19). The ACE-2 molecule is reported to be expressed by the oral mucosal epithelium. Thus, cells in oral mucosal tissues that express ACE-2, especially tongue epithelial cells, are oral niches that can act as intermediaries or reservoirs potential for COVID-19 transmission. Both virus and host microRNA (miRNA) play an important role in the pathology of viral infection. Here we review some papers related to the potential salivary microRNA (miRNA) exosome as a biomarker of COVID-19 infection. Therefore, miRNA in oral niches is important to be explored.