Computational study for identifying promising therapeutic agents of hydroxychloroquine analogues against SARS-CoV-2

Potential preventative impact of aloe-emodin nanoparticles on cerebral stroke-associated myocardial injury by targeting myeloperoxidase: In supporting with In silico and In vivo studies

The present study examined the potential neuroprotective effects of aloe-emodin (AE) nanoparticles on the cerebral stroke-associated target protein myeloperoxidase (MPO). We investigated the binding interactions between AE and MPO through molecular docking and molecular dynamics simulations. Molecular docking results indicated that AE exhibited a binding energy of -6.9 kcal/mol, whereas it was -7.7 kcal/mol for 2-{[3,5-bis(trifluoromethyl)benzyl]amino}-n-hydroxy-6-oxo-1,6-dihydropyrimidine-5-carboxamide (CCl). Furthermore, molecular dynamics studies demonstrated that AE possesses a stronger binding affinity (-57.137 ± 13.198 kJ/mol) than does CCl (-22.793 ± 30.727 kJ/mol), suggesting that AE has a more substantial inhibitory effect on MPO than does CCl. Despite the therapeutic potential of AE for neurodegenerative disorders, its bioavailability is limited within the body. A proposed hypothesis to enhance the bioavailability of AE is its conversion into aloe-emodin nanoparticles (AENP). The AENPs synthesized through a fabrication method were spherical with a consistent diameter of 104.4 ± 7.9 nm and a polydispersity index ranging from 0.525 to 0.586. In rats experiencing cerebral stroke, there was a notable increase in cerebral infarction size; abnormalities in electrocardiogram (ECG) and electroencephalogram (EEG) patterns; a decrease in brain and cardiac antioxidant activities; and an increase in myeloperoxidase levels compared to those in normal rats. Compared with AE treatment, AENP treatment significantly ameliorated cerebral infarction, normalized ECG and EEG patterns, enhanced brain and cardiac antioxidant activities, and reduced MPO levels in stroke rats. Histopathological evaluations revealed pronounced alterations in the rat hippocampus, with pyknotic nuclei, disarray and loosely packed cells, deterioration of cardiac muscle fibers, and extensive damage to cardiac myocytes, in contrast to those in normal rats. AENP treatment mitigated these pathological changes more effectively than AE treatment in both brain and cardiac cells. These findings support that AENP provides considerable protection against stroke-associated myocardial infarction.

Computational Studies of Selected Transition Metal Complexes as Potential Drug Candidates against the SARS-CoV-2 Virus

The earth has witnessed the greatest global health crisis due to the outbreak of the SARS-CoV-2 virus in late 2019, resulting in the pandemic COVID-19 with 3.38 million mortality and 163 million infections across 222 nations. Therefore, there is an urgent need for an effective therapeutic option against the SARS-CoV-2 virus. Transition metal complexes with unique chemical, kinetic and thermodynamic properties have recently emerged as the viable alternative for medicinal applications. Herein, the potential application of selected antiviral transition metal-based compounds against the SARS-CoV-2 virus was explored in silico. Initially, the transition metal-based antiviral compounds (1-5) were identified based on the structural similarity of the viral proteins (proteases, reverse transcriptase, envelop glycoproteins, etc.) of HIV, HCV, or Influenza virus with the proteins (S-protein, RNA-dependent RNA polymerase, proteases, etc) of SARS-CoV-2 virus. Hence the complexes (1-5) were subjected to ADME analysis for toxicology and pharmacokinetics report and further for the molecular docking calculations, selectively with the viral proteins of the SARS-CoV-2 virus. The molecular docking studies revealed that the iron-porphyrin complex (1) and antimalarial drug, ferroquine (2) could be the potential inhibitors of Main protease (Mpro) and spike proteins respectively of SARS-CoV-2 virus. The complex 1 exhibited high binding energy of -11.74 kcal/mol with the Mpro of SARS-CoV-2. Similarly ferroquine exhibitred binding energy of -7.43 kcal/mol against spike protein of SARS-CoV-2. The complex 5 also exhibited good binding constants values of -7.67, -8.68 and -7.82 kcal/mol with the spike protein, Mpro and RNA dependent RNA polymerase (RdRp) proteins respectively. Overall, transition metal complexes could provide an alternative and viable therapeutic solution for COVID-19.