Is there any relationship between serum zinc levels and angiotensin-converting enzyme 2 gene expression in patients with coronavirus disease 2019?

Background: The level of angiotensin-converting enzyme 2 (ACE2) expression in different tissues is essential in the sensitivity, symptoms and consequences of COVID-19 infection. It seems that zinc is involved in the structure of the ACE2 enzyme has been identified; nonetheless, the relationship between ACE2 expression and zinc serum levels in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected patients is still unclear. This study aimed to evaluate the expression of ACE2 in peripheral blood-derived immune cells of COVID-19 patients and its relationship with serum zinc levels.Methods: Thirty healthy subjects and thirty patients with COVID-19 were enrolled in this study. The COVID-19 infection was confirmed by positive real-time polymerase chain reaction (RT-PCR) and radiological data. Pe-ripheral blood samples were taken from healthy subjects and COVID-19 patients. Whole blood samples were also used to measure ACE2 gene expression by RT-PCR technique. The correlation matrix evaluated the relationship between ACE2 expression, serum zinc levels, and other related variables.Results: The outcomes showed no considerable alteration in serum zinc levels between patients and the control group. Likewise, the ACE2 gene expression results showed a significant decrease in this receptor's expression in COVID-19 patients compared with the healthy subjects. A significant positive correlation was observed between serum zinc level and ACE2 gene expression in patients with COVID-19.Conclusion: The immune system seems to reduce the mRNA expression of the ACE2 in the peripheral blood leukocytes following SARS-CoV-2 infection. Moreover, zinc deficiency can make patients more susceptible to SARS-CoV-2 infection.