ACE2 and diabetes mellitus: This evidence suggests a worst clinical scenario in DM including (i) higher ACE2 expression facilitating the SARS-CoV-2 infection, and (ii) a reduced ACE2/ACE ratio post SARS-CoV-2 infection triggering an heightened inflammatory and oxidative responses in diabetic patients increase the risk of a more severe form of COVID-19, especially in the acute pulmonary and severe hyperinflammation phase (Volpe et al., 2018).