Stigmasterol for 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.

AbstractTo attain promising pharmacotherapies, researchers have applied drug repurposing (DR) techniques to discover the candidate medicines to combat the coronavirus disease 2019 (COVID-19) outbreak. Although many DR approaches have been introduced for treating different diseases, only structure-based DR (SBDR) methods can be employed as the first therapeutic option against the COVID-19 pandemic because they rely on the rudimentary information about the diseases such as the sequence of the severe acute respiratory syndrome coronavirus 2 genome. Hence, to try out new treatments for the disease, the first attempts have been made based on the SBDR methods which seem to be among the proper choices for discovering the potential medications against the emerging and re-emerging infectious diseases. Given the importance of SBDR approaches, in the present review, well-known SBDR methods are summarized, and their merits are investigated. Then, the databases and software applications, utilized for repurposing the drugs against COVID-19, are introduced. Besides, the identified drugs are categorized based on their targets. Finally, a comparison is made between the SBDR approaches and other DR methods, and some possible future directions are proposed.

The ongoing COVID-19 pandemic has resulted in a global panic because of its continual evolution and recurring spikes. This serious malignancy is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the outbreak, millions of people have been affected from December 2019 till now, which has led to a great surge in finding treatments. Despite trying to handle the pandemic with the repurposing of some drugs, such as chloroquine, hydroxychloroquine, remdesivir, lopinavir, ivermectin, etc., against COVID-19, the SARS-CoV-2 virus continues its out-of-control spread. There is a dire need to identify a new regimen of natural products to combat the deadly viral disease. This article deals with the literature reports to date of natural products showing inhibitory activity towards SARS-CoV-2 through different approaches, such as in vivo, in vitro, and in silico studies. Natural compounds targeting the proteins of SARS-CoV-2—the main protease (Mpro), papain-like protease (PLpro), spike proteins, RNA-dependent RNA polymerase (RdRp), endoribonuclease, exoribonuclease, helicase, nucleocapsid, methyltransferase, adeno diphosphate (ADP) phosphatase, other nonstructural proteins, and envelope proteins—were extracted mainly from plants, and some were isolated from bacteria, algae, fungi, and a few marine organisms.