ACE2 and COVID-19: Since ACE2 negatively regulates RAAS activation mainly by converting angiotensin 1 and 2 into angiotensin 1–9 and 1–7, respectively, a downregulation of ACE2, accompanied by a simultaneous increase of pro-hypertensive angiotensin 2 levels in COVID-19 patients, have been suggested to contribute to increased blood pressure in the post-COVID period [104,125].