Methylxanthines as Potential Inhibitor of SARS-CoV-2: an In Silico Approach

Rajan Rolta; Deeksha Salaria; Bhanu Sharma; Oladoja Awofisayo; Olatomide A Fadare; Sonum Sharma; Chirag N Patel; Vikas Kumar; Anuradha Sourirajan; David J Baumler; Kamal Dev

doi:10.1007/s40495-021-00276-3

Methylxanthines as Potential Inhibitor of SARS-CoV-2: an In Silico Approach

Curr Pharmacol Rep. 2022;8(2):149-170. doi: 10.1007/s40495-021-00276-3. Epub 2022 Mar 8.

Authors

Affiliations

¹ Faculty of Applied Sciences and Biotechnology, Shoolini University, Solan, Himachal Pradesh India.
² Department of Pharmaceutical and Medical Chemistry, University of Uyo, Uyo, Nigeria.
³ Organic Chemistry Research Lab, Obafemi Awolowo University, Ile-Ife, Nigeria.
⁴ Department of Botany, Bioinformatics and Climate Change Impacts Management, University School of Science, Gujarat University, Ahmedabad, India.
⁵ University Institute of Biotechnology, Chandigarh University, Gharuan, Mohali, Punjab India.
⁶ Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN USA.

Abstract

The aim of the present study was to test the binding affinity of methylxanthines (caffeine/theine, methylxanthine, theobromine, theophylline and xanthine) to three potential target proteins namely Spike protein (6LZG), main protease (6LU7) and nucleocapsid protein N-terminal RNA binding domain (6M3M) of SARS-CoV-2. Proteins and ligand were generated using AutoDock 1.5.6 software. Binding affinity of methylxanthines with SARS-CoV-2 target proteins was determined using Autodock Vina. MD simulation of the best interacting complexes was performed using GROMACS 2018.3 (in duplicate) and Desmond program version 2.0 (academic version) (in triplicate) to study the stabile interaction of protein-ligand complexes. Among the selected methylxanthines, theophylline showed the best binding affinity with all the three targets of SARS-CoV-2 (6LZG - 5.7 kcal mol^-1, 6LU7 - 6.5 kcal mol^-1, 6M3M - 5.8 kcal mol^-1). MD simulation results of 100 ns (in triplicate) showed that theophylline is stable in the binding pockets of all the selected SARS-CoV-2 proteins. Moreover, methylxanthines are safer and less toxic as shown by high LD₅₀ value with Protox II software as compared to drug chloroquine. This research supports the use of methylxanthines as a SARS-CoV-2 inhibitor. It also lays the groundwork for future studies and could aid in the development of a treatment for SARS-CoV-2 and related viral infections.

Supplementary information: The online version contains supplementary material available at 10.1007/s40495-021-00276-3.

Keywords: 6M3M; AutoDock Vina; MD simulation; Main protease (6LU7); Methylxanthines; SARS-CoV-2 spike protein (6LZG).

Publication types

Review