In silico screening of chalcones and their derivatives as potential inhibitors of spike proteins and ACE2 enzymes for SARS-CoV-2 treatment

The COVID-19 pandemic causing acute respiratory syndrome is a significant public health problem. Drugs that can treat this disease are currently a high priority. The SARS-CoV-2 spike protein and human ACE2 enzyme receptor, which both play important roles in virus entry into the host cell, are promising therapeutic targets for inhibiting viral infection. This research evaluates the potential of chalcone compounds to inhibit the spike proteins and ACE2 enzymes through molecular docking in silico approaches. Based on the ChemFaces database, we collected 92 chalcone compounds. These compounds were further docked to target the active sites of spike protein and human ACE2. After comparing the binding energies of the 92 compounds to artemisinin, ribavirin, and lopinavir, which have inhibitory activity to these protein targets of SARS-CoV-2, we chose 20 out of the 92 compounds that had a higher ability to inhibit the protein targets than the reference inhibitors. Next, five phytochemical compounds with the best binding energy were selected, which included flavanomarein, sarcandrone B, sarcandrone A, calyxin H, and sieboldin. Then, Lipinski's 5 rule was used to evaluate the druglike properties of these compounds. Predictive ADME/tox filtering tests were also applied to the top docked compounds. The results suggest that sarcandrone B has good pharmacokinetic properties, which should be further explored as an anti-SARS-CoV-2. To confirm these findings, experimental studies are recommended.

Coumarins and chalcones against SARS-CoV-2

Coronavirus disease-2019 (COVID-19) is a contagious infection caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), leading to a pandemic and traumatizing the world. To prevent the spread of virus, infected people were isolated as per the strict protocols. Due to the genome sequence of the virus being strikingly similar to that of SARS-CoV, many antiviral medicines previously approved to treat SARS and MERS are now being repurposed for the plausible treatment COVID-19. To combat SARS-CoV-2, a slew of experimental and clinical medicine and vaccine trials are currently underway worldwide. In the fight against COVID-19 infection, a variety of natural substances are also being searched extensively. Coumarins and chalcones are two important natural chemical classes. They can be found in a wide range of natural products and have many pharmacological effects. SARS-CoV-2 and other coronaviruses were successfully treated with these drugs, which showed significant antiviral activity. This chapter discusses the possible role of coumarins and chalcones in SARS-CoV-2 infection treatment. © 2023 Elsevier Inc. All rights reserved.

Studies of Cytotoxicity Effects, SARS-CoV-2 Main Protease Inhibition, and in Silico Interactions of Synthetic Chalcones.

SARS-CoV-2 main protease (Mpro ) plays an essential role in proteolysis cleavage that promotes coronavirus replication. Thus, attenuating the activity of this enzyme represents a strategy to develop antiviral agents. We report inhibitory effects against Mpro of 40 synthetic chalcones, and cytotoxicity activities, hemolysis, and in silico interactions of active compounds. Seven of them bearing a (E)-3-(furan-2-yl)-1-arylprop-2-en-1-one skeleton (10, 28, and 35-39) showed enzyme inhibition with IC50 ranging from 13.76 and 36.13 µM. Except for 35 and 36, other active compounds were not cytotoxic up to 150 µM against THP-1 and Vero cell lines. Compounds 10, and 35-39 showed no hemolysis while 28 was weakly hemotoxic at 150 µM. Moreover, molecular docking showed interactions between compound 10 and Mpro (PDBID 5RG2 and 5RG3) with proximity to cys145 and His41, suggesting a covalent binding. Products of the reaction between chalcones and cyclohexanethiol indicated that this binding could be a Michael addition type.

Natural and Semi-Synthetic Flavonoid Anti-SARS-CoV-2 Agents for the Treatment of Long COVID-19 Disease and Neurodegenerative Disorders of Cognitive Decline.

The aim of this review is to highlight the beneficial attributes of flavonoids, a diverse family of widely-distributed polyphenolic phytochemicals that have beneficial cell and tissue protective properties. Phytochemicals are widely distributed in plants, herbs and shrubs used in traditional complimentary medical formulations for centuries. The bioactive components that convey beneficial medicinal effects in these complex herbal preparations are now being identified using network pharmacology and molecular docking procedures that identify their molecular targets. Flavonoids have anti-oxidant, anti-inflammatory, antiviral, antibacterial and anti-cancer properties that have inspired the development of potent multifunctional derivatised flavonoids of improved efficacy. The antiviral properties of flavonoids and the emergence of the severe acute respiratory syndrome (SARS-CoV-2) pandemic has resulted in a resurgence of interest in phytochemicals in the search for efficacious compounds that can prevent viral infection or replication, with many promising plant compounds identified. Promising semi-synthetic flavonoid derivatives have also been developed that inhibit multiple pathological neurodegenerative processes; these offer considerable promise in the treatment of diseases of cognitive decline. Clinical trials are currently being undertaken to evaluate the efficacy of dietary supplements rich in flavonoids for the treatment of virally-mediated diseases. Such trials are expected to identify flavonoids with cell and tissue protective properties that can be harnessed in biomedical applications that may serve as supportive adjunctive procedures to conventional anti-viral drug therapies against diseases such as COVID-19.

Interaction of panduratin A and derivatives with the SARS-CoV-2 main protease (mpro): a molecular docking study.

Panduratin A (Pa-A) is a prenylated cyclohexenyl chalcone isolated from the rhizomes of the medicinal and culinary plant Boesenbergia rotunda (L.) Mansf., commonly called fingerroots. Both an ethanolic plant extract and Pa-A have shown a marked antiviral activity against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), responsible for the COVID-19 pandemic disease. Pa-A functions as a protease inhibitor inhibiting infection of human cells by the virus. We have modeled the interaction of Pa-A, and 26 panduratin analogues with the main protease (Mpro) of SARS-CoV-2 using molecular docking. The natural product 4-hydroxypanduratin showed a higher Mpro binding capacity than Pa-A and isopanduratin A. The interaction with MPro of all known panduratin derivatives (Pa-A to Pa-Y) have been compared, together with more than 60 reference products. Three compounds emerged as potential robust MPro binders: Pa-R, Pa-V, Pa-S, with a binding capacity significantly higher than 4-OH-Pa-A and Pa-A. The empirical energy of interaction (ΔE) calculated with the best compound in the panduratin series, Pa-R bound to Mpro, surpassed that measured with the top reference protease inhibitors such a ruprintrivir, lufotrelvir, and glecaprevir. Structure-binding relationships are discussed. Compounds with a flavanone moiety (PA-R/S) are the best binders, better than those with a chromene unit (Pa-F/G). The extended molecules (such as Pa-V) exhibit good Mpro binding, but the dimeric compound Pa-Y is too long and protrudes outside the binding cavity. The work provides novel ideas to guide the design of new molecules interacting with Mpro.Communicated by Ramaswamy H. Sarma.

Panduratin A is the main bioactive molecule in extracts of the medicinal plant Boesenbergia rotunda.Extracts of B. rotunda and Pa-A have shown activity against the virus SARS-CoV-2.We modeled the interaction of 27 panduratin derivatives with the main protease (M^pro) of the virus.Three molecules (Pa-R/V/S) revealed high M^pro binding capacity compared to reference compounds.Structure­binding relationships are discussed, to guide the design of compounds to treat COVID-19.

Exploring the mechanism of Platycodonis Radix-Licorice for prevention and treatment of COVID-19 based on network pharmacology and molecular docking

Objective: To investigate the possible mechanism of Platycodonis Radix-Licorice drug pair in the intervention of COVID-19 by using network pharmacology and molecular docking technique. Methods The database TCMSP was retrieved for the chemical constituents and targets of Platycodonis Radix-Licorice drug pair. Coronavirus disease targets were screened by the Gene Cards, OMIM,TTD, PharmGkb and DrugBank database. Cytoscape 3.7.2 software was used to construct the drug-component-target network. The PPI(protein-protein interaction) network was obtained by drug-disease intersection targets, and the core genes were found through CytoNCA plug-in. Meanwhile, GO(gene ontology) analysis and KEGG(Kyoto encyclopedia of genes and genomes) pathway analysis were performed by using Bioconductor database to predict the mechanism. AutoDock Tools 1.5.6 software was used to simulate the molecular docking of the main active ingredients with the novel coronavirus key binding site protein [SARS-CoV-2 main protease(severe acute respiratory syndrome coronavirus 2 main protease, Mpro) and ACE2(angiotensin converting enzyme 2)]. Results A total of 7 active ingredients of Platycodonis Radix,92 active ingredients of Licorice,2766 drug targets, and 674 disease targets were obtained, and 67 drug-disease common targets were excavated. The key targets involved RELA,STAT1,MAPK3,TP53,MAPK1,MAPK8,STAT3,MAPK14,IL1 B and TNF by the database STRING and CytoNCA plug-in.Go enrichment analysis showed that the main functions of Platycodonis Radix-Licorice drug pair on the intervention of COVID-19 were antioxidant reaction, cell respond to chemical stress, regulation of apoptotic signaling pathways, reaction to lipopolysaccharides and reaction to bacteria-derived molecules, etc.. KEGG pathways involved Coronavirus disease-COVID-19 pathway, IL-17 signaling pathway and so on, were mainly associated with immune response, inflammation-related pathways, inhibition of viral infection, and other inhibition of cancer. The molecular docking results showed that glepidotin A,quercetin, licochalcone a and luteolin had good binding ability with Mpro and ACE2. Conclusion Platycodonis Radix-Licorice drug pair act on SARS-CoV-2 through multiple components, multiple targets, and multiple channel combination. And the main active ingredients have a fine binding ability with Mpro and ACE2. The method can provide theoretical support for the possibility of traditional Chinese medicine(TCM) against COVID-19.

Flavonoids as an effective sensitizer for anti-cancer therapy: insights into multi-faceted mechanisms and applicability towards individualized patient profiles.

Cost-efficacy of currently applied treatments is an issue in overall cancer management challenging healthcare and causing tremendous economic burden to societies around the world. Consequently, complex treatment models presenting concepts of predictive diagnostics followed by targeted prevention and treatments tailored to the personal patient profiles earn global appreciation as benefiting the patient, healthcare economy, and the society at large. In this context, application of flavonoids as a spectrum of compounds and their nano-technologically created derivatives is extensively under consideration, due to their multi-faceted anti-cancer effects applicable to the overall cost-effective cancer management, primary, secondary, and even tertiary prevention. This article analyzes most recently updated data focused on the potent capacity of flavonoids to promote anti-cancer therapeutic effects and interprets all the collected research achievements in the frame-work of predictive, preventive, and personalized (3P) medicine. Main pillars considered are: - Predictable anti-neoplastic, immune-modulating, drug-sensitizing effects; - Targeted molecular pathways to improve therapeutic outcomes by increasing sensitivity of cancer cells and reversing their resistance towards currently applied therapeutic modalities.

In silico pharmacokinetic and molecular docking studies of natural flavonoids and synthetic indole chalcones against essential proteins of SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is distinctly infective and there is an ongoing effort to find a cure for this pandemic. Flavonoids exist in many diets as well as in traditional medicine, and their modern subset, indole-chalcones, are effective in fighting various diseases. Hence, these flavonoids and structurally similar indole chalcones derivatives were studied in silico for their pharmacokinetic properties including absorption, distribution, metabolism, excretion, toxicity (ADMET) and anti-SARS-CoV-2 properties against their proteins, namely, RNA dependent RNA polymerase (rdrp), main protease (Mpro) and Spike (S) protein via homology modelling and docking. Interactions were studied with respect to biology and function of SARS-CoV-2 proteins for activity. Functional/structural roles of amino acid residues of SARS-CoV-2 proteins and, the effect of flavonoid and indole chalcone interactions which may cause disease suppression are discussed. The results reveal that out of 23 natural flavonoids and 25 synthetic indole chalcones, 30 compounds are capable of Mpro deactivation as well as potentially lowering the efficiency of Mpro function. Cyanidin may inhibit RNA polymerase function and, Quercetin is found to block interaction sites on the viral spike. These results suggest flavonoids and their modern pharmaceutical cousins, indole chalcones are capable of fighting SARS-CoV-2. The in vitro anti-SARS-CoV-2 activity of these 30 compounds needs to be studied further for complete understanding and confirmation of their inhibitory potential.