Targeting zinc metalloenzymes in coronavirus disease 2019

Several lines of evidence support a link between the essential element zinc and the coronavirus disease 2019 (COVID-19). An important fact is that zinc is present in proteins of humans and of viruses. Some zinc sites in viral enzymes may serve as drug targets and may liberate zinc ions, thus leading to changes in intracellular concentration of zinc ions, while increased intracellular zinc may induce biological effects in both the host and the virus. Drugs such as chloroquine may contribute to increased intracellular zinc. Moreover, clinical trials on the use of zinc alone or in addition to other drugs in the prophylaxis/treatment of COVID-19 are ongoing. Thereby, we aim to discuss the rationale for targeting zinc metalloenzymes as a new strategy for the treatment of COVID-19.