Kaempferol 3-O-rutinoside for COVID-19

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.

AbstractHypericum perforatum and Echinacea are reported to have antiviral activities against several viral infections. In this study, H. perforatum (St. John’s Wort) and Echinacea were tested in vitro using Vero E6 cells for their anti-viral effects against the newly identified Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) through its infectious cycle from 0 to 48 h post infection. The hypericin of H. perforatum and the different parts (roots, seeds, aerial) of two types of Echinacea species (Echinacea purpurea and Echinacea angustifolia) were tested for their anti-viral activities to measure the inhibition of viral load using quantitative real-time polymerase chain reaction (qRT-PCR) on cell culture assay. Interestingly, the H. perforatum-Echinacea mixture (1:1 ratio) of H. perforatum and Echinacea was tested as well on SARS-CoV-2 and showed crucial anti-viral activity competing H. perforatum then Echinacea effects as anti-viral treatment. Therefore, the results H. perforatum and Echinacea species, applied in this study showed significant anti-viral and virucidal effects in the following order of potency: H. perforatum, H. perforatum-Echinacea mixture, and Echinacea on SARS-CoV-2 infectious cycle. Additionally, molecular simulation analysis of the compounds with essential proteins (Mpro and RdRp) of the SARS-CoV-2 revealed the most potent bioactive compounds such as Echinacin, Echinacoside, Cyanin, Cyanidin 3-(6''-alonylglucoside, Quercetin-3-O-glucuronide, Proanthocyanidins, Rutin, Kaempferol-3-O-rutinoside, and Quercetin-3-O-xyloside. Thus, based on the outcome of this study, it is demanding the setup of clinical trial with specific therapeutic protocol.