To the editor
We read interesting correspondence reported by Liu et al.[1] We would like to remind the forgotten aspects of ACE 2 enzyme.
ACE 2 enzyme doesn’t only hydrolyze angiotensin proteins, it also hydrolyzes ghrelin, Apelin-13 and other proteins.[2] ARB and ACEI may increase ACE2 enzyme, which may increase the infection and decrease apelin-13 and ghrelin levels.
Ghrelin and Apelin-13 are reported to be neuroprotective.[3,4] Also, after ischemic injury, ghrelin seems to improve recovery.[4] In COVID patients, taking these drugs may be more prone to stroke and other neurological complications. Decrease in ghrelin levels may increase the virus induced acute lung injury.5
Decreased level of these hormones may be responsible from several complications in COVID-19.
The other aspects of diseases and drugs that may effect ACE2 expression[1] is they may also effect the response of drugs targetting COVID-19. We don’t know if vaccine efficiency may also be affected by these factors.
Footnotes
Conflict of Interest
None declared.
References
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