ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have triggered a recent pandemic of respiratory disease and affected almost every country all over the world. A large amount of natural bioactive compounds are under clinical investigation for various diseases. In particular, marine natural compounds are gaining more attention in the new drug development process. The present study aimed to identify potential marine-derived inhibitors against the target proteins of COVID-19 using a computational approach. Currently, 16 marine clinical-level compounds were selected for computational screening against the 4 SARS-CoV-2 main proteases. Computational screening resulted from the best drug candidates for each target based on the binding affinity scores and amino acid interactions. Among these, five marine-derived compounds, namely, chrysophaentin A (-6.6 kcal/mol), geodisterol sulfates (-6.6 kcal/mol), hymenidin (-6.4 kcal/mol), plinabulin (-6.4 kcal/mol), and tetrodotoxin (-6.3 kcal/mol) expressed minimized binding energy and molecular interactions, such as covalent and hydrophobic interactions, with the SARS CoV-2 main protease. Using molecular dynamic studies, the root-mean-square deviation (RMSD), root-mean-square fluctuation (RMSF), radius of gyration (ROG), and hydrogen bond (H-Bond) values were calculated for the SARS-CoV-2 main protease with a hymenidin docked complex. Additionally, in silico drug-likeness and pharmacokinetic property assessments of the compounds demonstrated favorable druggability. These results suggest that marine natural compounds are capable of fighting SARS-CoV-2. Further in vitro and in vivo studies need to be carried out to confirm their inhibitory potential.
ABSTRACT
SARS-CoV-2 is a newly identified coronavirus that causes the respiratory disease called coronavirus disease 2019 (COVID-19). With an urgent need for therapeutics, we lack a full understanding of the molecular basis of SARS-CoV-2-induced cellular damage and disease progression. Here, we conducted transcriptomic analysis of human PBMCs, identified significant changes in mitochondrial, ion channel, and protein quality-control gene products. SARS-CoV-2 proteins selectively target cellular organelle compartments, including the endoplasmic reticulum and mitochondria. M-protein, NSP6, ORF3A, ORF9C, and ORF10 bind to mitochondrial PTP complex components cyclophilin D, SPG-7, ANT, ATP synthase, and a previously undescribed CCDC58 (coiled-coil domain containing protein 58). Knockdown of CCDC58 or mPTP blocker cyclosporin A pretreatment enhances mitochondrial Ca2+ retention capacity and bioenergetics. SARS-CoV-2 infection exacerbates cardiomyocyte autophagy and promotes cell death that was suppressed by cyclosporin A treatment. Our findings reveal that SARS-CoV-2 viral proteins suppress cardiomyocyte mitochondrial function that disrupts cardiomyocyte Ca2+ cycling and cell viability.