MicroRNA­28­3p inhibits angiotensin­converting enzyme 2 ectodomain shedding in 293T cells treated with the spike protein of severe acute respiratory syndrome coronavirus 2 by targeting A disintegrin and metalloproteinase 17.

Severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) is the virus that causes coronavirus disease 2019. Angiotensin­converting enzyme 2 (ACE2) is the SARS­CoV binding site and is ubiquitously expressed in endothelial cells of several organs, with the highest levels in the cardiovascular system, kidney and lungs. A disintegrin and metalloproteinase 17 (ADAM17) is involved in ectodomain shedding of ACE2. In the present study, reverse­transcription­quantitative PCR, transfection, TUNNEL assay, dual­luciferase activity assay and western blotting were conducted to investigate the effects of microRNA (miR)­28­3p on ADAM17­dependent shedding of the ACE2 ectodomain following treatment with the spike protein (S­protein) of SARS­CoV­2. It was found that miR­28­3p was significantly downregulated in 293T cells treated with 100 ng/ml of S­protein for 24 h at 37˚C, which led to upregulation of ADAM17. In addition, the expression of ADAM17 and miR­28­3p were negatively correlated based on Pearson's correlation test in 293T cells treated with S­protein for 24 h. Overexpression of miR­28­3p and inhibition of ADAM17 regulated 293T cell viability, apoptosis and ACE2 ectodomain shedding. It was also demonstrated that ADAM17 was the target gene of miR­28­3p and that miR­28­3p negatively regulated ADAM17 expression. Notably, the inhibition of ADAM17 expression blocked the effects of miR­28­3p inhibitor on proliferation, apoptosis and ACE2 ectodomain shedding in 293T cells treated with S­protein. The findings of the present study suggested that miR­28­3p inhibits ADAM17­dependent ACE2 ectodomain shedding in 293T cells treated with the S­protein of SARS­CoV­2, which suggested the potential therapeutic role of miR­28­3p mimic in the prevention and treatment of patients with SARS­CoV­2.