Figure 1. Potential mechanisms mediating increased risk of hemorrhagic stroke in COVID-19 patients. The RBD of SARS-CoV-2’ spike protein interacts with ACE2, leading to ACE2 downregulation. ACE2 deficiency impairs endothelial function in cerebral arteries and determines an increase in Ang-II levels, which elevates BP through activation of AT1 receptors (AT1R). Simultaneously, reduced ACE2 leads to a decrease in Ang (1-7) levels, weakening its vasculo-protective effects mediated by Mas receptor (MasR) activation.