ABSTRACT
italic>Anoectochilus roxburghii liquid (spray, a hospital preparation of Wu Mengchao Hepatobiliary Hospital of Fujian Medical University) has shown a good clinical treatment effect during the COVID-19 pandemic, but its material basis and mechanism of action are still unclear. In this study, network pharmacology and molecular docking methods were used to predict the molecular mechanism of A. roxburghii liquid against COVID-19, and pharmacodynamic experiments in vitro were conducted to study the interaction between the current targets with clear preventive and therapeutic effects and the key components of A. roxburghii liquid. UPLC-MS and database were used to compare and analyze the active ingredients in the liquid, and 17 potential active ingredients with good drug-like properties were screened by in vivo pharmacokinetics process in SwissADME database. SwissTargetPrediction and GeneCards were searched to find 93 common targets. Cytoscape 3.8.2 software was used to construct the "component-target" network map, and the Metascape platform was used for gene function annotation and pathway enrichment analysis. It was found that the extract could regulate the positive response to external stimuli, inflammatory response, cytokine production and other biological processes by binding the active ingredients such as isorhamnetin, kaempferol, luteolin, quercetin and apigenin to the common targets (NOS3, MPO, MMP3, etc.), and play an anti-COVID-19 role. In the angiotensin-converting enzyme 2 (ACE2) activity inhibition assay, it was found that the stock solution of A. roxburghii liquid (for spray), and the supernatant after removing polysaccharides (mainly containing flavonoids) could to some extent inhibit the activity of ACE2. Crucially, in the experiment of 2019-nCOV-S pseudovirus infecting HEK-293T-ACE2 cells, we found that A. roxburghii liquid may exert anti-COVID-19 effects by blocking the binding of SARS-CoV-S protein to ACE2.