ACE2 and acute respiratory distress syndrome: In ARDS, the pulmonary circulation and Renin-Angiotensin System (RAS) play a very important role; this is where ACE2 becomes notorious since low expression leads to an increase in capillary permeability that triggers pulmonary edema, possibly mediated by an increase in Ang II and its stimulation on AT1R receptors, where other mediators such as eicosanoids, prostaglandins E2 and I2 that regulate changes in capillary permeability also participate (78).