Alterations in the expression of serum-derived exosome-enclosed inflammatory microRNAs in Covid-19 patients.

Introduction: MicroRNAs in exosomes play a role in biological processes such as inflammation and Epithelial-mesenchymal transition (EMT). In EMT, epithelial cells undergo phenotypic changes and become similar to mesenchymal cells. EMT increases the invasion and metastasis of cancer cells. We aimed to evaluate the expression levels of miRNA-21, miRNA-218, miRNA-155, and miRNA-10b, which are effective in the pathway of inflammation and EMT in serum-derived exosome of COVID-19 patients.

Method: Blood samples were taken from 30 patients with COVID-19 and five healthy individuals as a control group. After separating the serum from the collected blood, the exosomes were purified from the serum. Relative expression of microRNAs was measured by real-time PCR method.

Results: The relative expression of miRNA-21, miRNA-218, and miRNA-155 in serum-derived exosomes of patients with COVID-19 had a significant increase (p < 0.0001). Also, the relative expression of miRNA-10b was significantly increased in the patient group (p < 0.01), but the changes in the expression level of miRNA-10b were not as significant as the changes in the expression level of other microRNAs.

Conclusion: miRNA-21, miRNA-218, miRNA-155, and miRNA-10b are involved in the pathogenesis of COVID-19 disease, and their transmission by exosomes leads to pathogenic lesions and problems in other parts of the body.