ACE2 and COVID-19
The angiotensin-converting enzyme 2 (ACE2) receptor is part of the dual
system - renin-angiotensin-system (RAS) - consisting of an
ACE-Angiotensin-II-AT1R axis and an
ACE-2-Angiotensin-(1-7)-Mas axis. AT1R is involved in
most of the effects of Ang II, including oxidative stress
generation,22 which in turn upregulates
AT1R 23. In metabolic disorders and
with older age, there is an upregulation of the AT1R
axis leading to pro-inflammatory, pro-fibrotic effects in the
respiratory system, and to insulin resistance.24SARS-CoV-2 binds to its receptor ACE2 and exploits it for entry into the
cell. The ACE2 downregulation, as a result of SARS-Cov-2 binding,
enhances the AT1R axis. 25