In Silico Insight into the Inhibitory Effects of Active Antidiabetic Compounds from Medicinal Plants Against SARS-CoV-2 Replication and Post-translational Modification

Background: The recent reemergence of the coronavirus (COVID-19) caused by the virus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has prompted the search for effective treatments in the forms of drugs and vaccines. Aim(s): In this regard, we performed an in silico study on 39 active antidiabetic compounds of medicinal plants to provide insight into their possible inhibitory potentials against SARS-CoV-2 replications and post-translational modifications. Top 12 active antidiabetic compounds with potential for dual inhibition of the replications and post-translational modifications of SARS-CoV-2 were ana-lyzed. Result(s): Boswellic acids, celastrol, rutin, sanguinarine, silymarin, and withanolides expressed binding energy for 3-chymotrypsin-like protease (3CLpro) (-8.0 to-8.9 Kcal/mol), papain-like protease (PLpro) (-9.1 to-10.2 Kcal/mol), and RNA-dependent RNA polymerase (RdRp) (-8.5 to-9.1 Kcal/-mol) which were higher than the reference drugs (Lopinavir and Remdesivir) used in this study. Sanguinarine, silymarin, and withanolides are the most druggable phytochemicals among other phy-tochemicals as they follow Lipinski's rule of five analyses. Sanguinarine, silymarin, and withano-lides expressed moderate solubility with no hepatotoxicity, while silymarin and withanolides could not permeate the blood-brain barrier and showed no Salmonella typhimurium reverse mutation as-say (AMES) toxicity, unlike sanguinarine from the predictive absorption, distribution, metabolism, elimination, and toxicity (ADMET) studies. Conclusion(s): Sanguinarine, silymarin, and withanolides could be proposed for further experimental studies for their development as possible phytotherapy for the COVID-19 pandemic.Copyright © 2022 Bentham Science Publishers.

A Computational Insight on the Inhibitory Potential of 8-Hydroxydihydrosanguinarine (8-HDS), a Pyridone Containing Analog of Sanguinarine, against SARS CoV2.

The unprecedented global pandemic of COVID-19 has created a daunting scenario urging an immediate generation of therapeutic strategy. Interventions to curb the spread of viral infection primarily include setting targets against the virus. Here in this study we target S protein to obstruct the viral attachment and entry and also the M pro to prevent the viral replication. For this purpose, the interaction of S protein and M pro with phytocompounds, sanguinarine and eugenol, and their derivatives were studied using computational tools. Docking studies gave evidence that 8-hydroxydihydrosanguinarine (8-HDS), a derivative of sanguinarine, showed maximum binding affinity with both the targets. The binding energies of the ligand with S protein and M pro scored to be ΔGb -9.4 Kcal/mol and ΔGb -10.3 Kcal/mol, respectively. MD simulation studies depict that the phytocompound could effectively cause structural perturbations in the targets which would affect their functions. 8-Hydroxydihydrosanguinarine distorts the α-helix in the secondary structure of M pro and RBD site of S protein. Protein-protein interaction study in presence of 8-hydroxydihydrosanguinarine also corroborate the above findings which indicate that this polyphenol interferes in the coupling of S protein and ACE2. The alterations in protonation of M pro suggest that the protein structure undergoes significant structural changes at neutral pH. ADME property of 8-hydroxydihydrosanguinarine indicates this could be a potential drug. This makes the phyto-alkaloid a possible therapeutic molecule for anti COVID-19 drug design.

DNA intercalators alkaloids as Potential candidates to fight COVID-19 disease: Systematic review

The main objective of the current systematic review was to report the antiviral and anti-inflammatory effects of bioactive molecules class known as alkaloids against SARS-COV-2 disease. These bioactive compounds were characterized by their potential replication inhibitory ability by DNA intercalating effect, and might be powerful agents against infections caused by several viruses, therefore it can be a viable strategy for COVID-19 management. PubMed, ScienceDirect, Google Scholar and SpringerLink, databases have been chosen to look for keywords like DNA intercalators, alkaloids, antiviral activity, anti-inflammatory effect, coronavirus, SARS-CoV-2. Two reviewers have evaluated the quality of 60 articles extracted from the four databases till 15th of May 2021, using inclusions and exclusions criteria, 25 papers were accepted and treated in this systematic review, performed based on PRISMA protocol. Results disclosed that alkaloids have key roles in viral replication inhibition, quinine and emetine showed a noticeable therapeutic effect against SARS-COV-2 virus, however emetine revealed modifications in the electrocardiogram (ECG), unlike sanguinarine and berberine that showed low human toxicity. Tetrandrine, fangchinoline and cepharantine could be classified as remedies in case of Coronavirus ailment. Chelidonine, coptisine, skimmianine, protropine, palmatine, cinchonine, harmine and dictamine represented important agents for clinical researches or as precursors for antiviral drug’s formulation.

Therapeutic potential of plant secondary metabolites in treatment of respiratory viral diseases: A review

Respiratory viral infections are a major public health concern because of their global occurrence, ease of spread and considerable morbidity and mortality. Medical treatments for viral respiratory diseases primarily involve providing relief from symptoms like pain and discomfort rather than treating the infection. Very few antiviral medications have been approved with restrictive usage, high cost, unwanted side effects and limited availability. Plants with their unique metabolite composition and high remedial values offer unique preventive and therapeutic efficacy in treatment of viral infections. The present review is focused on the types and mode of action of plant secondary metabolites that have been used successfully ί in the treatment of infections caused by respiratory viruses like Influenza, SARS, MERS, RSV etc. Plant metabolites such as phenolics, alkaloids, terpenoids and oligosaccharides inhibit attachment and entry of the virus. Others such as flavonoids, viz quercetin and baicalein, alkaloids viz sanguinarine, berberine and emetine, specific lipids and fatty acids prevent viral replication and protein synthesis. These metabolites have the potential to be used as lead molecules that can be optimized to develop potent drugs for effectively combating pandemics caused by respiratory viruses.