Nitric oxide induced by Indian ginseng root extract inhibits Infectious Bursal Disease virus in chicken embryo fibroblasts in vitro

A comprehensive review of phytochemicals of Withania somnifera (L.) Dunal (Solanaceae) as antiviral therapeutics

Viruses have caused millions and billions of infections and high mortality rates without successful immunization due to a lack of antiviral drugs approved for clinical use. Therefore, the discovery of novel antiviral drugs is impertinent and natural products are excellent alternative sources. Withania somnifera (L.) Dunal (Solanaceae) is recognized as one of the most significant herbs in the Ayurvedic system and it had been utilized in various biological actions for more than 3000 years. This review aimed to discuss the therapeutic effects and associated molecular mechanisms of Withania somnifera (WS) and its phytochemicals, withanolides against various viruses in preclinical and clinical settings towards developing potential inhibitors which could target virus proteins or their respective host cell receptors. WS was reported to attenuate coronavirus disease 2019 (COVID-19), serve as a potential ligand against the herpes simplex virus (HSV) DNA polymerase, suppress Alzheimer’s disease progression by inhibiting the cytotoxicity induced by the human immunodeficiency virus 1 (HIV-1)-activated beta-amyloid (Aβ), and attenuate the neuraminidase activity of H1N1 influenza. WS root extracts have also reduced the mortality rates and stress levels in tilapia infected with tilapia lake virus (TiLV), and stimulated antiviral nitric oxide formation in chicks infected with infectious bursal disease (IBD). With increasing evidence from previous literatures, further in vitro and in vivo investigations of WS against other viral infections may provide promising results.

Graphical Abstract

Culinary spices and herbs in managing early and long-COVID-19 complications: A comprehensive review

Human race is preparing for the upsurge and aftermath of COVID-19 pandemic complicated by novel variants, new waves, variable mortality rate, and post-COVID complications. Despite use of repurposed drugs, symptomatic treatments and licensing of multiple vaccines, the daily number of cases and rate of transmission are significant. Culinary spices and herbs have been historically used in pandemic and non-pandemic times to reduce respiratory viral burden. Specific food items and culinary spices can boost the levels of protective immunity and also offer therapeutic benefits against impervious bugs via well-known as well as less-known but scientifically testable mechanisms. Here, we analyzed the phytochemicals profile of Ayurvedic herbs and inferred from the clinical trials/observational studies to provide a focused and succinct perspective on the relevance of "food-based" traditional decoction to moderate COVID-19 disease and long-COVID via modulation of immunity and reinstatement of homeostasis. We also underscore the druggable targets in pathogenesis of COVID-19 which are relevant to the ongoing clinical trials using spices and herbs. This information will provide a strong scientific rationale for standardization of the traditional herbs-based therapies and adopting the use of herbs, spices, and their formulations for reducing SARS-CoV-2 transmission, long-COVID symptoms, and COVID-19 disease progression.

In silico analysis and molecular docking studies of natural compounds of Withania somnifera against bovine NLRP9

CONTEXT

NLRP9 is a member of nucleotide-binding domain leucine-rich repeat-containing receptors and is found to be associated with many inflammatory diseases. In the current scenario, the identification of promising anti-inflammatory compounds from natural sources by repurposing approach is still relevant for the early prevention and effective management of the disease.

METHODS

In the present study, we docked bioactives of Ashwagandha (Withanoside IV, Withanoside V, Withanolide A, Withanolide B, and Sitoindoside IX) and two control drugs against bovine NLRP9 protein. ADME/T analysis was used to determine the physiochemical properties of compounds and standard drugs. Molecular modeling was used to evaluate the correctness and quality of protein structures. In silico docking analysis revealed Withanolide B had the highest binding affinity score of -10.5 kcal/mol, whereas, among control drugs, doxycycline hydrochloride was most effective (-10.3 kcal/mol). The results of this study revealed that bioactives of Withania somnifera could be promising inhibitors against bovine NLRP9. In the present study, molecular simulation was used to measure protein conformational changes over time. The Rg value was found to be 34.77A°. RMSD and B-factor were also estimated to provide insights into the flexibility and mobile regions of protein structure. A functional protein network interaction was constructed from information collected from non-curative sources as protein-protein interactions (PPI) that play an important role in determining the function of the target protein and the ability of the drug molecule. Thus, in the present situation, it is important to identify bioactives with the potential to combat inflammatory diseases and provide strength and immunity to the host. However, there is still a need to study in vitro and in vivo to further support these findings.

Withaniasomnifera phytochemicals possess SARS-CoV-2 RdRp and human TMPRSS2 protein binding potential

ABSTRACT

Coronavirus disease-19 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has infected approximately 26 million people and caused more than 6 million deaths globally. Spike (S)-protein on the outer surface of the virus uses human trans-membrane serine protease-2 (TMPRSS2) to gain entry into the cell. Recent reports indicate that human dipeptidyl peptidase-4 inhibitors (DPP4 or CD26) could also be utilized to check the S-protein mediated viral entry into COVID-19 patients. RNA dependent RNA polymerase (RdRp) is another key virulence protein of SARS-CoV-2 life cycle. The study aimed to identify the potential anti-SARS-CoV-2 inhibitors present in Withania somnifera (Solanaceae) using computer aided drug discovery approach. Molecular docking results showed that flavone glycoside, sugar alcohol, and flavonoid present in W. somnifera showed - 11.69, - 11.61, - 10.1, - 7.71 kcal/mole binding potential against S-protein, CD26, RdRp, and TMPRSS2 proteins. The major standard inhibitors of the targeted proteins (Sitagliptin, VE607, Camostat mesylate, and Remdesivir) showed the - 7.181, - 6.6, - 5.146, and - 7.56 kcal/mole binding potential. Furthermore, the lead phytochemicals and standard inhibitors bound and non-bound RdRp and TMPRSS2 proteins were subjected to molecular dynamics (MD) simulation to study the complex stability and change in protein conformation. The result showed energetically favorable and stable complex formation in terms of RMSD, RMSF, SASA, Rg, and hydrogen bond formation. Drug likeness and physiochemical properties of the test compounds exhibited satisfactory results. Taken together, the present study suggests the presence of potential anti-SARS-CoV-2 phytochemicals in W. somnifera that requires further validation in in vitro and in vivo studies.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s42535-022-00404-4.

Frequently Used Allopathic and Traditional Medicine for COVID-19 Treatment and Feasibility of Their Integration

To date, no satisfactory treatment for COVID-19 is available. This review reported few recent updates regarding the drugs (allopathy/traditional medicines) used for the treatment of COVID-19 concerning clinical studies. Content of the article spotlight the contribution of allopathic and Ayurvedic drugs to the scientific basis for utilization as a potential therapy against COVID-19 infection and provide new insights on the integration of allopathy and traditional medicine. It advocated the combination of these two systems of treatment will ascertain their integrations, and there would be a good possibility and scope for developing a model of integration in the management of COVID-19. Provided discussion may help researchers, physicians, and healthcare policymakers to encourage for effective and integrated use of allopathic and Ayurvedic medicines to control the COVID-19 pandemic more effectively.

Phytochemicals present in Indian ginseng possess potential to inhibit SARS-CoV-2 virulence: A molecular docking and MD simulation study

Coronaviruses are deadly and contagious pathogens that affects people in different ways. Researchers have increased their efforts in the development of antiviral agents against coronavirus targeting Mpro protein (main protease) as an effective drug target. The present study explores the inhibitory potential of characteristic and non-characteristic Withania somnifera (Indian ginseng) phytochemicals (n ≈ 100) against SARS-Cov-2 Mpro protein. Molecular docking studies revealed that certain W. somnifera compounds exhibit superior binding potential (-6.16 to -12.27 kcal/mol) compared to the standard inhibitors (-2.55 to -6.16 kcal/mol) including nelfinavir and lopinavir. The non-characteristic compounds (quercetin-3-rutinoside-7-glucoside, rutin and isochlorogenic acid B) exhibited higher inhibitory potential in comparison to characteristic W. somnifera compounds withanolide and withanone. Molecular dynamics (MD) simulation studies of the complex for 100 ns confirm favorable and stable binding of the lead molecule. The MMPBSA calculation of the last 10 ns of the protein-ligand complex trajectory exhibited stable binding of quercetin-3-rutinoside-7-glucoside at the active site of SARS-Cov-2 Mpro. Taken together, the study demonstrates that the non-characteristic compounds present in W. somnifera possess enhanced potential to bind SARS-Cov-2 Mpro active site. We further recommend in vitro and in vivo experimentation to validate the anti-SARS-CoV-2 potential of these lead molecules.

Withania somnifera (L.) Dunal: Opportunity for Clinical Repurposing in COVID-19 Management

As the COVID-19 pandemic is progressing, the therapeutic gaps in conventional management have highlighted the need for the integration of traditional knowledge systems with modern medicine. Ayurvedic medicines, especially Ashwagandha (Withania somnifera (L.) Dunal, WS), may be beneficial in the management of COVID-19. WS is a widely prescribed Ayurvedic botanical known as an immunomodulatory, antiviral, anti-inflammatory, and adaptogenic agent. The chemical profile and pharmacological activities of WS have been extensively reported. Several clinical studies have reported its safety for use in humans. This review presents a research synthesis of in silico, in vitro, in vivo, and clinical studies on Withania somnifera (L.) Dunal (WS) and discusses its potential for prophylaxis and management of COVID-19. We have collated the data from studies on WS that focused on viral infections (HIV, HSV, H1N1 influenza, etc.) and noncommunicable diseases (hypertension, diabetes, cancer, etc.). The experimental literature indicates that WS has the potential for 1) maintaining immune homeostasis, 2) regulating inflammation, 3) suppressing pro-inflammatory cytokines, 4) organ protection (nervous system, heart, lung, liver, and kidney), and 5) anti-stress, antihypertensive, and antidiabetic activities. Using these trends, the review presents a triangulation of Ayurveda wisdom, pharmacological properties, and COVID-19 pathophysiology ranging from viral entry to end-stage acute respiratory distress syndrome (ARDS). The review proposes WS as a potential therapeutic adjuvant for various stages of COVID-19 management. WS may also have beneficial effects on comorbidities associated with the COVID-19. However, systematic studies are needed to realize the potential of WS for improving clinical outcome of patients with COVID-19.

Emerging trends from COVID-19 research registered in the Clinical Trials Registry - India

Since the beginning of the year, the deadly coronavirus pandemic, better known as coronavirus disease 2019 (COVID-19), brought the entire world to an unprecedented halt. In tandem with the global scenario, researchers in India are actively engaged in the conduct of clinical research to counter the pandemic. This review attempts to provide a comprehensive overview of the COVID-19 research in India including design aspects, through the clinical trials registered in the Clinical Trials Registry - India (CTRI) till June 5, 2020. One hundred and twenty two registered trials on COVID-19 were extracted from the CTRI database. These trials were categorized into modern medicine (n=42), traditional medicine (n=67) and miscellaneous (n=13). Of the 42 modern medicine trials, 28 were on repurposed drugs, used singly (n=24) or in combination (n=4). Of these 28 trials, 23 were to evaluate their therapeutic efficacy in different severities of the disease. There were nine registered trials on cell- and plasma-based therapies, two phytopharmaceutical trials and three vaccine trials. The traditional medicine trials category majorly comprised Ayurveda (n=45), followed by homeopathy (n=14) and others (n=8) from Yoga, Siddha and Unani. Among the traditional medicine category, 31 trials were prophylactic and 36 were therapeutic, mostly conducted on asymptomatic or mild-to-moderate COVID-19 patients. This review would showcase the research being conducted on COVID-19 in the country and highlight the research gaps to steer further studies.

Coronil, a Tri-Herbal Formulation, Attenuates Spike-Protein-Mediated SARS-CoV-2 Viral Entry into Human Alveolar Epithelial Cells and Pro-Inflammatory Cytokines Production by Inhibiting Spike Protein-ACE-2 Interaction

PURPOSE

Coronil is a tri-herbal formulation containing extracts from Withania somnifera, Tinospora cordifolia, and Ocimum sanctum. Recently, it was shown that Coronil rescued humanized zebrafish from SARS-CoV-2 induced pathologies. Based on reported computational studies on the phytochemicals present in Coronil, it could be a potential inhibitor of SARS-CoV-2 entry into the host cell and associated cytokines' production.

METHODS

Through an ELISA-based biochemical assay, effects of Coronil on interaction between ACE-2 and different mutants of viral spike (S) protein, crucial for viral invasion of host cell, were evaluated. Additionally, using recombinant pseudoviruses having SARS-CoV-2 spike (S) protein in their envelopes and firefly luciferase reporter in their genomes, effects of Coronil on virus entry into human alveolar epithelial cells were evaluated through luciferase assay. UHPLC profiled Coronil also modulated S-protein mediated production of pro-inflammatory cytokines in A549 cells, like interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α), as evaluated through RT-qPCR and ELISA.

RESULTS

Coronil effectively inhibited the interaction of ACE-2 not only with the wild-type S protein (SWT) but also with its currently prevalent and more infectious variant (SD614G) and another mutant (SW436R) with significantly higher affinity toward ACE-2. Treatment with Coronil significantly reduced the increased levels of IL-6, IL-1β, and TNF-α in A549 cells incubated with different S-protein variants in a dose-dependent manner. Likewise, it also prevented the SARS-CoV-2 S-protein pseudotyped vesicular stomatitis virus (VSVppSARS-2S) mediated cytokine response in these cells by reducing entry of pseudoviruses into host cells.

CONCLUSION

Coronil prevented SARS-CoV-2 S-protein mediated viral entry into A549 cells by inhibiting spike protein-ACE-2 interactions. SARS-CoV-2 S protein induced inflammatory cytokine response in these cells was also moderated by Coronil.

Identification of bioactive molecule from Withania somnifera (Ashwagandha) as SARS-CoV-2 main protease inhibitor

SARS-CoV-2 is the causative agent of COVID-19 and has been declared as pandemic disease by World Health Organization. Lack of targeted therapeutics and vaccines for COVID-2019 have triggered the scientific community to develop new vaccines or drugs against this novel virus. Many synthetic compounds and antimalarial drugs are undergoing clinical trials. The traditional medical practitioners widely use Indian medicinal plant Withania somnifera (Ashwagandha) natural constituents, called withanolides for curing various diseases. The main protease (M^pro) of SARS-CoV-2 plays a vital role in disease propagation by processing the polyproteins which are required for its replication. Hence, it denotes a significant target for drug discovery. In the present study, we evaluate the potential of 40 natural chemical constituents of Ashwagandha to explore a possible inhibitor against main protease of SARS-CoV-2 by adopting the computational approach. The docking study revealed that four constituents of Ashwagandha; Withanoside II (-11.30 Kcal/mol), Withanoside IV (-11.02 Kcal/mol), Withanoside V (-8.96 Kcal/mol) and Sitoindoside IX (-8.37 Kcal/mol) exhibited the highest docking energy among the selected natural constituents. Further, MD simulation study of 100 ns predicts Withanoside V possess strong binding affinity and hydrogen-bonding interactions with the protein active site and indicates its stability in the active site. The binding free energy score also correlates with the highest score of -87.01 ± 5.01 Kcal/mol as compared to other selected compounds. In conclusion, our study suggests that Withanoside V in Ashwagandha may be serve as a potential inhibitor against M^pro of SARS-CoV-2 to combat COVID-19 and may have an antiviral effect on nCoV.Communicated by Ramaswamy H. Sarma.

Therapeutic opportunities to manage COVID-19/SARS-CoV-2 infection: Present and future

A severe form of respiratory disease - COVID-19, caused by SARS-CoV-2 infection, has evolved into a pandemic resulting in significant morbidity and mortality. The unabated spread of the disease is due to lack of vaccine and effective therapeutic agents against this novel virus. Hence, the situation demands an immediate need to explore all the plausible therapeutic and prophylactic strategies that can be made available to stem the spread of the disease. Towards this effort, the current review outlines the key aspects of the pathobiology associated with the morbidity and mortality in COVID-19 patients, which includes a viral response phase and an exaggerated host response phase. The review also summarizes therapeutic agents that are currently being explored along with those with potential for consideration. The broad groups of therapeutic agents discussed include those that: (i) block viral entry to host cells, (ii) block viral replication and survival in host cells, and (iii) dampen exaggerated host immune response. The various kinds of pharmaceutical prophylactic options that may be followed to prevent COVID-19 have also been discussed.

Dietary supplementation with Withania somnifera root powder ameliorates experimentally induced Infectious Bursal Disease in chicken

Infectious Bursal Disease (IBD) is an economically important, immunosuppressive viral disease of chicken. Withania somnifera, a well-known Indian medicinal plant and functional food, finds extensive ethnomedicinal and ethnoveterinary use in the subcontinent. Root extracts of Withania somnifera have been shown to inhibit IBD virus (IBDV) in vitro. The effect of dietary supplementation with whole root powder of Withania somnifera was studied in chicken experimentally infected with IBDV. Dietary supplementation with the root powder improved erythrocytic indices, biochemical parameters, bursal weight index, and lymphocyte stimulation indices, and reduced histopathological insult in the infected birds. Viral load decreased to less than one-fourth in the birds receiving dietary supplementation with Withania somnifera root powder. It could be concluded that continued supplementation of IBDV-infected chicken with Withania somnifera root powder alleviated virus-induced stress and histological and immunological alterations and reduced viral persistence in the host.