Vitamin C Inhibits Angiotensin-Converting Enzyme-2 in Isolated Rat Aortic Ring

Aims: The study aimed to assess the inhibitory effect of Vitamin C on angiotensin-converting enzyme 2. Background: Coronavirus disease 2019 (COVID-19) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which uses angiotensin-converting enzyme 2 (ACE-II) as the first route to infect human cells. Accordingly, agents with potential inhibition of ACE-II receptors might be effective in the prevention and management of COVID-19. Objective: The goal of this work was to assess the possible inhibitory effect of ACE-II on ascorbic acid using an ex vivo approach based on the inhibition of diminazene-induced vasorelaxation. Materials and Methods: In the present study, diminazene was used as a known specific inhibitor of ACE-II. Then, the vasorelaxant effect of ascorbic acid on diminazene-induced relaxation was examined using isolated aortic rings. All experiments of this study were evaluated on isolated aortic rings precontracted by epinephrine. Results: The results confirmed that diminazene-induced vasorelaxation in a dose-dependent manner. More interestingly, ascorbic acid inhibited diminazene-induced vasorelaxation in a dose-dependent manner. Conclusion: This investigation provides valuable experimental proof of the efficacy of ascorbic acid (Vitamin C) on inhibiting ex vivo vascular angiotensin-converting enzyme II, which is known among the pharmacological targets of anti-COVID-19 drugs.