In their article, Esler et al.[1] note that angiotensin-converting enzyme 2 (ACE2) acts as a SARS-CoV-2 receptor and angiotensin receptor blockers increase ACE2 expression. They hypothesize that angiotensin receptor blockers (ARB) could perhaps be harmful in the COVID-19 pandemic.
Studies have found that patients with high blood pressure are more likely to develop acute respiratory distress syndrome (ARDS) or progress from ARDS to death in COVID-19 pneumonia [2,3].
Regarding the role of the renin–angiotensin system in ARDS, other authors found different results.
Kuba et al.[4,5] using ACE2 knockout mice showed that ACE2 protects murine lungs from ARDS. Injection of SARS-CoV Spike into mice worsened acute lung failure in vivo that could be attenuated by blocking the renin–angiotensin pathway.
ACE2 converts angiotensin II to angiotensin-(1–7). In other animal models, ACE2 activity was reduced in ARDS and treatment with a cyclic form of angiotensin-(1–7) attenuated the inflammatory response and decreased lung injury scores [6]. These data indicate that ACE2 plays an important role in ARDS development and the activation of pulmonary renin–angiotensin system influences the pathogenesis of ARDS.
At the present time, we do not know whether the upregulation of ACE2 in lung can be harmful or beneficial for patients with SARS-CoV-2 infection.
It will be very important to know whether in the studies performed by researchers in China, among patients with hypertension, there was a higher mortality in patients taking ARB than in patients treated with other antihypertensive drugs.
ACKNOWLEDGEMENTS
Conflicts of interest
There are no conflicts of interest.
REFERENCES
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