Identification of SARS-CoV-2 spike protein inhibitors from Urtica dioica to develop herbal-based therapeutics against COVID-19

Objective: The high transmission rate and mutations of SARS-CoV-2 have made it a global pandemic, and the shortage of any effective clinical treatment has created such a commotion. There are some synthetic antiviral drugs, such as remdesivir and lopinavir that are being repurposed to treat SARS-CoV-2, but all of these demonstrate extreme side effects in humans. Hence, promoting herbal-based drug development has become crucial as they are cost-effective and have lesser or no side effects. Urtica dioica is abundant in the Himalayan region and the compounds present in it have shown significant antiviral and anti-SARS activity. Therefore, molecular docking studies were performed to identify SARS-CoV-2 spike protein inhibitors from U. dioica to combat the COVID-19 disease. Materials and Methods: Compounds from U. dioica were screened using the bioinformatic approach, and subsequently, these compounds were docked with the S1 subunit of the COVID-19 spike protein (PDB ID: 6YOR). Molecular docking was carried out using the PyRx software (0.8 version) and further examined by employing the Discovery Studio Visualizer. Results: About all the selected compounds showed significant binding energy (e.g., beta-sitosterol: −10.3 kcal/mol) in contrast to the control chloroquine phosphate. This binding was observed with the spike protein residues that were common in the old strain and the more contagious newly modified B.1.1.7 strain of SARS-CoV-2. Conclusions: Thus, our study can be used in effective drug development against SARS-CoV-2 and its mutant strains also.