Which ones, when and why should renin-angiotensin system inhibitors work against COVID-19?

• Published in: Advances in biological regulation Vol. 81; p. 100820
• Main Authors: Montanari, Mariele, Canonico, Barbara, Nordi, Evelyn, Vandini, Daniela, Barocci, Simone, Benedetti, Serena, Carlotti, Eugenio, Zamai, Loris
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-08-2021; Elsevier BV; Published by Elsevier Ltd
• Subjects: ACE2; ADAM17; ADAM17 Protein - antagonists & inhibitors; ADAM17 Protein - biosynthesis; Angiotensin; Angiotensin I - metabolism; Angiotensin-converting enzyme 2; Angiotensin-Converting Enzyme 2 - antagonists & inhibitors; Angiotensin-Converting Enzyme 2 - biosynthesis; Coronaviruses; COVID-19; COVID-19 - metabolism; COVID-19 Drug Treatment; Endocrine system; Enzymes; Gene Expression Regulation, Enzymologic; Humans; Hyperactivity; Hypertension; Hypotheses; Inflammation; Peptide Fragments - metabolism; Peptides; Positive feedback; RAS inhibitors; Renin; Renin-Angiotensin System; SARS-CoV-2 - metabolism; Severe acute respiratory syndrome; Severe acute respiratory syndrome coronavirus 2; Spike Glycoprotein, Coronavirus - antagonists & inhibitors; Spike Glycoprotein, Coronavirus - metabolism; Spike N-Terminal domain; Thromboembolism; Thrombosis; Up-Regulation; Vaccines; Viral diseases; Zinc-chelating agents; Zinc-metalloproteases; ADAM17; RAS inhibitors; Zinc-chelating agents; Renin-angiotensin system; Zinc-metalloproteases; Spike N-Terminal domain
• ISSN: 2212-4926; 2212-4934
• DOI: 10.1016/j.jbior.2021.100820

The article describes the possible pathophysiological origin of COVID-19 and the crucial role of renin-angiotensin system (RAS), providing several “converging” evidence in support of this hypothesis. SARS-CoV-2 has been shown to initially upregulate ACE2 systemic activity (early phase), which can subsequently induce compensatory responses leading to upregulation of both arms of the RAS (late phase) and consequently to critical, advanced and untreatable stages of COVID-19 disease. The main and initial actors of the process are ACE2 and ADAM17 zinc-metalloproteases, which, initially triggered by SARS-CoV-2 spike proteins, work together in increasing circulating Ang 1–7 and Ang 1–9 peptides and downstream (Mas and Angiotensin type 2 receptors) pathways with anti-inflammatory, hypotensive and antithrombotic activities. During the late phase of severe COVID-19, compensatory secretion of renin and ACE enzymes are subsequently upregulated, leading to inflammation, hypertension and thrombosis, which further sustain ACE2 and ADAM17 upregulation. Based on this hypothesis, COVID-19-phase-specific inhibition of different RAS enzymes is proposed as a pharmacological strategy against COVID-19 and vaccine-induced adverse effects. The aim is to prevent the establishment of positive feedback-loops, which can sustain hyperactivity of both arms of the RAS independently of viral trigger and, in some cases, may lead to Long-COVID syndrome.