Renin-angiotensin-aldosterone system and COVID-19 infection

Alexandre, Joachim; Cracowski, Jean-Luc; Richard, Vincent; Bouhanick, Béatrice

Summary With the multiplication of COVID-19 cases due to SARS COV2, some concerns about angiotensin-converting enzyme 1 (ACE1) inhibitors (ACEi) and angiotensin II type 1 receptor blockers (ARB) have emerged. Because SARS COV2 utilizes ACE2 (angiotensin-converting enzyme 2) as a membrane receptor to enter target cells, the fear that ACEi or ARB might increase the risk of developing severe or fatal severe acute respiratory syndrome in case of COVID-19 infection emerged. The present article discusses these concerns. ACE2 is a membrane-bound enzyme (carboxypeptidase) that contributes to the inactivation of angiotensin II and therefore physiologically counters angiotensin II effects. Due to different structural structures with ACE1, ACE2 is insensitive to ACEIs. Although ARBs and ACEi have been shown to upregulate ACE2 tissue expression in experimental animals, evidence was not always consistent in human studies. Therefore, to date, the exact impact of bot ARBs and ACEis on COVID-19 infection remains unknown and preliminary results are in favor of a protective role of ACEis and ARBs. Finally, some studies support the hypothesis that elevated ACE2 membrane expression and tissue activity by administration of ARB and/or infusion of soluble ACE2 could confer protective properties against inflammatory tissue damage in COVID-19 infection. In summary, based on the currently available evidence and as recommended by several medical societies, ACEi or ARB should not be discontinued because of concerns with COVID-19 infection, except when the hemodynamic situation is precarious and case-by-case adjustment is required.