Network pharmacology and molecular docking identified IL-6 as a critical target of Qing Yan He Ji against COVID-19.

Since the coronavirus disease 2019 (COVID-19) outbreak, although have controlled, severe acute respiratory syndrome coronavirus 2 is constantly mutating and affects people's health. FDA has approved Paxlovid and Molnupiravir for COVID-19 treatment, however, they have not been approved for children under 12 years old. Therefore, it is urgent to explore new drugs for treating COVID-19 in children. As a traditional Chinese medicine, Qing Yan He Ji (QYHJ) has been widely used as an antiviral in our hospital. Therefore, we presumed that it may be ideal for treating COVID-19 and explored its therapeutic effect in patients with COVID-19. The targets and underlying mechanisms of QYHJ against COVID-19 in children were investigated using bioinformatics. QYHJ target sets, and related target genes of COVID-19 were retrieved from public databases. Subsequently, gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed to investigate the potential mechanism of QYHJ against COVID-19. Finally, molecular docking was carried out to analyze the affinity between the effective molecule and the target protein. A total of 15 bioactive ingredients of QYHJ and 111 predicted potential targets of QYHJ against COVID-19 were screened. A protein-protein interaction network and subnetworks identified 21 core target genes. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that QYHJ functions against COVID-19 primarily through antiviral and anti-inflammatory effects. Molecular docking of interleukin-6 (IL-6) revealed that 5 active compounds had relatively stable binding activities with IL-6. Molecular dynamics simulation was performed for molecular docking results, showing IL-6-(4aS,6aR,6aS,6bR,8aR,10R,12aR,14bS)-10-hydroxy-2,2,6a,6b,9,9,12a-heptamethyl-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylic acid (4aS) complex, IL-6-stigmasterol complex, IL-6-poriferasterol complex, IL-6-sitosterol complex, and IL-6-beta-sitosterol complex had relatively good binding stability. In conclusion, the multi-component and multi-target intervention of QYHJ against COVID-19 is closely related to antiviral and anti-inflammatory activities, which provides a theoretical basis for clinical application.