Angiotensin-converting enzyme 2 (ACE2) and COVID-19
COVID-19 is more severe in older adults and/or patients with
comorbidities, such as diabetes, obesity, kidney disease or
hypertension, suggesting a role for insulin
resistance.15 Although differences exist between
countries, the same risk factors for severity were found globally16-20, suggesting common mechanisms. Moreover, the
severe outcomes of COVID-19 - including lung damage, cytokine storm or
endothelial damage - appear to exist globally, again suggesting common
mechanisms.
The angiotensin-converting enzyme 2 (ACE-2) is part of the dual system,
the renin-angiotensin-system (RAS), including the
ACE-Angiotensin-II-AT1R axis. AT1R is
involved in most Angiotensin II effects, including oxidative stress
generation, pro-inflammatory, pro-fibrotic effects in the respiratory
system, endothelial damage and insulin resistance.21,22 SARS-CoV-2 binds to and downregulates ACE-2,
enhancing the AT1R axis 23, likely to
be associated with insulin resistance 24,25 but also
to severe outcomes of COVID-19.