Oroxylin A is a severe acute respiratory syndrome coronavirus 2‐spiked pseudotyped virus blocker obtained from Radix Scutellariae using angiotensin‐converting enzyme II/cell membrane chromatography

Gao, Jiapan; Ding, Yuanyuan; Wang, Yuejin; Liang, Peida; Zhang, Liyang; Liu, Rui

The current worldwide outbreak of the coronavirus disease 2019 (COVID‐19) has been declared a public health emergency. The angiotensin‐converting enzyme II (ACE2) has been reported as the primary host‐cell receptor for severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), the causative virus of COVID‐19. In this study, we screened ACE2 ligands from Radix Scutellariae and investigated its suppressive effect on SARS‐CoV‐2 spiked pseudotyped virus in vitro. HEK293T cells stably expressing ACE2 receptors (ACE2 cells) were used to provide the receptor for the ACE2/cell membrane chromatography (CMC) method used for analysis. The SARS‐CoV‐2‐spiked pseudotyped virus was used to examine the anti‐viropexis effect of the screened compounds in ACE2 cells. Molecular docking and the surface plasmon resonance (SPR) assay were used to determine the binding properties. Oroxylin A exhibited an appreciable suppressive effect against the entrance of the SARS‐CoV‐2‐spiked pseudotyped virus into ACE2 cells, which showed good binding to ACE2 as determined using SPR and CMC. Oroxylin A was shown to be a potential candidate in the treatment for COVID‐19 by virtue of its blocking the entrance of SARS‐CoV‐2 into ACE2 cells by specifically binding to the ACE2 receptor.