A latest report shows that elevated blood glucose levels facilitate SARS-CoV-2 replication and ACE2 expression in monocytes accumulated in the lung of COVID-19 patients, which induces mitochondrial reactive oxygen species (ROS) production by stabilizing hypoxia-inducible factor-1α (HIF-1α) and promoting glycolysis (Codo et al., 2020). This evidence concerns the gene ACE2 and COVID-19.