Withanolides from Withania somnifera as an immunity booster and their therapeutic options against COVID-19

Unraveling antiviral efficacy of multifunctional immunomodulatory triterpenoids against SARS-COV-2 targeting main protease and papain-like protease

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be over, but its variants continue to emerge, and patients with mild symptoms having long COVID is still under investigation. SARS-CoV-2 infection leading to elevated cytokine levels and suppressed immune responses set off cytokine storm, fatal systemic inflammation, tissue damage, and multi-organ failure. Thus, drug molecules targeting the SARS-CoV-2 virus-specific proteins or capable of suppressing the host inflammatory responses to viral infection would provide an effective antiviral therapy against emerging variants of concern. Evolutionarily conserved papain-like protease (PLpro) and main protease (Mpro) play an indispensable role in the virus life cycle and immune evasion. Direct-acting antivirals targeting both these viral proteases represent an attractive antiviral strategy that is also expected to reduce viral inflammation. The present study has evaluated the antiviral and anti-inflammatory potential of natural triterpenoids: azadirachtin, withanolide_A, and isoginkgetin. These molecules inhibit the Mpro and PLpro proteolytic activities with half-maximal inhibitory concentrations (IC50) values ranging from 1.42 to 32.7 μM. Isothermal titration calorimetry (ITC) analysis validated the binding of these compounds to Mpro and PLpro. As expected, the two compounds, withanolide_A and azadirachtin, exhibit potent anti-SARS-CoV-2 activity in cell-based assays, with half-maximum effective concentration (EC50) values of 21.73 and 31.19 μM, respectively. The anti-inflammatory roles of azadirachtin and withanolide_A when assessed using HEK293T cells, were found to significantly reduce the levels of CXCL10, TNFα, IL6, and IL8 cytokines, which are elevated in severe cases of COVID-19. Interestingly, azadirachtin and withanolide_A were also found to rescue the decreased type-I interferon response (IFN-α1). The results of this study clearly highlight the role of triterpenoids as effective antiviral molecules that target SARS-CoV-2-specific enzymes and also host immune pathways involved in virus-mediated inflammation.

In silico evaluation of pharmacokinetics properties of withanolides and simulation of their biological activities against Alzheimer's disease

The withanolides are naturally occurring steroidal lactones found mainly in plants of the Solanaceae family. The subtribe Withaninae includes species like Withania sominifera, which are a source of many bioactive withanolides. In this work, we selected and evaluate the ADMET-related properties of 91 withanolides found in species of the subtribe Withaninae computationally, to predict the relationship between their structures and their pharmacokinetic profiles. We also evaluated the interaction of these withanolides with known targets of Alzheimer's disease (AD) through molecular docking and molecular dynamics. Withanolides presented favorable pharmacokinetic properties, like high gastrointestinal absorption, lipophilicity (logP ≤ 5), good distribution and excretion parameters, and a favorable toxicity profile. The specie Withania aristata stood out as an interesting source of the promising withanolides classified as 5-ene with 16-ene or 17-ene. These withanolides presented a favourable pharmacokinetic profile and were also highlighted as the best candidates for inhibition of AD-related targets. Our results also suggest that withanolides are likely to act as cholinesterase inhibitors by interacting with the catalytic pocket in an energy favorable and stable way.Communicated by Ramaswamy H. Sarma.

Steroidal lactones from Withania somnifera effectively target Beta, Gamma, Delta and Omicron variants of SARS-CoV-2 and reveal a decreased susceptibility to viral infection and perpetuation: a polypharmacology approach

Prevention from disease is presently the cornerstone of the fight against COVID-19. With the rapid emergence of novel SARS-CoV-2 variants, there is an urgent need for novel or repurposed agents to strengthen and fortify the immune system. Existing vaccines induce several systemic and local side-effects that can lead to severe consequences. Moreover, elevated cytokines in COVID-19 patients with cancer as co-morbidity represent a significant bottleneck in disease prognosis and therapy. Withania somnifera (WS) and its phytoconstituent(s) have immense untapped immunomodulatory and therapeutic potential and the anticancer potential of WS is well documented. To this effect, WS methanolic extract (WSME) was characterized using HPLC. Withanolides were identified as the major phytoconstituents. In vitro cytotoxicity of WSME was determined against human breast MDA-MB-231 and normal Vero cells using MTT assay. WSME displayed potent cytotoxicity against MDA-MB-231 cells (IC50: 66 µg/mL) and no effect on Vero cells in the above range. MD simulations of Withanolide A with SARS-CoV-2 main protease and spike receptor-binding domain as well as Withanolide B with SARS-CoV spike glycoprotein and SARS-CoV-2 papain-like protease were performed using Schrödinger. Stability of complexes followed the order 6M0J-Withanolide A > 6W9C-Withnaolide B > 5WRG-Withanolide B > 6LU7-Withanolide A. Maximum stable interaction(s) were observed between Withanolides A and B with SARS-CoV-2 and SARS-CoV spike glycoproteins, respectively. Withanolides A and B also displayed potent binding to pro-inflammatory markers viz. serum ferritin and IL-6. Thus, WS phytoconstituents have the potential to be tested further in vitro and in vivo as novel antiviral agents against COVID-19 patients having cancer as a co-morbidity.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-023-00184-y.

Pharmacoinformatic approach to identify potential phytochemicals against SARS-CoV-2 spike receptor-binding domain in native and variants of concern

Severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) pathogenesis is initiated by the binding of SARS-CoV-2 spike (S) protein with the angiotensin-converting enzyme 2 receptor (ACE2R) on the host cell surface. The receptor-binding domain (RBD) of the S protein mediates the binding and is more prone to mutations resulting in the generation of different variants. Recently, molecules with the potential to inhibit the interaction of S protein with ACE2R have been of interest due to their therapeutic value. In this context, the present work was performed to identify potential RBD binders from the Indian medicinal plant's phytochemical database through virtual screening, molecular docking, and molecular dynamic simulation. Briefly, 1578 compounds filtered from 9596 phytochemicals were chosen for screening against the RBD of the native SARS-CoV-2 S protein. Based on the binding energy, the top 30 compounds were selected and re-docked individually against the native and five variants of concern (VOCs: alpha, beta, gamma, delta, and omicron) of SARS-CoV-2. Four phytochemicals, namely withanolide F, serotobenine, orobanchol, and gibberellin A51, were found to be potential RBD binders in native and all SARS-CoV-2 VOCs. Among the four, withanolide F exhibited lower binding energy (- 10.84 to - 8.56 kcal/mol) and better ligand efficiency (- 0.3 to - 0.25) against all forms of RBD and hence was subjected to a 100 ns MD simulation which confirmed its stringent binding to the RBDs in native and VOCs. The study prioritizes withanolide F as a prospective COVID-19 (Coronavirus disease) therapeutic agent based on the observations. It warrants deeper investigations into the four promising leads for understanding their precise therapeutic value.

New perspective on the immunomodulatory activity of ginsenosides: Focus on effective therapies for post-COVID-19

More than 700 million confirmed cases of Coronavirus Disease-2019 (COVID-19) have been reported globally, and 10-60% of patients are expected to exhibit "post-COVID-19 symptoms," which will continue to affect human life and health. In the absence of safer, more specific drugs, current multiple immunotherapies have failed to achieve satisfactory efficacy. Ginseng, a traditional Chinese medicine, is often used as an immunomodulator and has been used in COVID-19 treatment as a tonic to increase blood oxygen saturation. Ginsenosides are the main active components of ginseng. In this review, we summarize the multiple ways in which ginsenosides affect post-COVID-19 symptoms, including inhibition of lipopolysaccharide, tumor necrosis factor signaling, modulation of chemokine receptors and inflammasome activation, induction of macrophage polarization, effects on Toll-like receptors, nuclear factor kappa-B, the mitogen-activated protein kinase pathway, lymphocytes, intestinal flora, and epigenetic regulation. Ginsenosides affect virus-mediated tissue damage, local or systemic inflammation, immune modulation, and other links, thus alleviating respiratory and pulmonary symptoms, reducing the cardiac burden, protecting the nervous system, and providing new ideas for the rehabilitation of patients with post-COVID-19 symptoms. Furthermore, we analyzed its role in strengthening body resistance to eliminate pathogenic factors from the perspective of ginseng-epidemic disease and highlighted the challenges in clinical applications. However, the benefit of ginsenosides in modulating organismal imbalance post-COVID-19 needs to be further evaluated to better validate the pharmacological mechanisms associated with their traditional efficacy and to determine their role in individualized therapy.

Withania somnifera extracts induced attenuation of HIV-1: a mechanistic approach to restrict viral infection

BACKGROUND

Several anti-retroviral drugs are available against Human immunodeficiency virus type-1, but have multiple adverse side effects. Hence, there is an incessant compulsion for effectual anti-retroviral agents with minimal or no intricacy. Traditionally, natural products have been the most successful source for the development of new medications. Withania somnifera, also known as Ashwagandha, is the utmost treasured medicinal plant used in Ayurveda, which holds the potential to give adaptogenic, immunomodulatory, and antiviral effects. However, its effect on HIV-1 replication at the cellular level has never been explored. Herein, we focused on the anti-HIV-1 activity and the probable mechanism of action of hydroalcoholic and aqueous extracts of Withania somnifera roots and its phytomolecules.

METHODS

The cytotoxicity of the extracts was determined through MTT assay, while the in vitro anti-HIV-1 activity was assessed in TZM-bl cells against the HIV-1 strains of X4 and R5 subtypes. Results were confirmed in peripheral blood mononuclear cells, using the HIV-1 p24 antigen assay. Additionally, the mechanism of action was determined through the Time of Addition assay, which was further validated through the series of enzymatic assays, i.e. HIV-1 Integrase, Reverse transcriptase, and Protease assays. To explore the role of the identified active metabolites of Withania somnifera in antiretroviral activity, molecular docking analyses were performed against these key HIV-1 replication enzymes.

RESULTS

The hydroalcoholic and aqueous extracts of Withania somnifera roots were found to be safer at the sub-cytotoxic concentrations and exhibited their ability to inhibit replication of two primary isolates of HIV-1 through cell-associated and cell-free assays, in dose-dependent kinetics. Several active phytomolecules found in Withania somnifera successfully established hydrogens bonds in the active binding pocket site residues responsible for the catalytic activity of HIV replication and therefore, signifying their role in the attenuation of HIV-1 infection as implied through the in silico molecular docking studies.

CONCLUSIONS

Our research identified both the hydroalcoholic and aqueous extracts of Withania somnifera roots as potent inhibitors of HIV-1 infection. The in silico analyses also indicated the key components of Withania somnifera with the highest binding affinity against the HIV-1 Integrase by 12-Deoxywithastramonolide and 27-Hydroxywithanone, HIV-1 Protease by Ashwagandhanolide and Withacoagin, and HIV-1 Reverse transcriptase by Ashwagandhanolide and Withanolide B, thereby showing possible mechanisms of HIV-1 extenuation. Overall, this study classified the role of Withania somnifera extracts and their active compounds as potential agents against HIV-1 infection.

Phytochemicals of Withania somnifera as a Future Promising Drug against SARS-CoV-2: Pharmacological Role, Molecular Mechanism, Molecular Docking Evaluation, and Efficient Delivery

Coronavirus disease (COVID-19) has killed millions of people since first reported in Wuhan, China, in December 2019. Intriguingly, Withania somnifera (WS) has shown promising antiviral effects against numerous viral infections, including SARS-CoV and SARS-CoV-2, which are contributed by its phytochemicals. This review focused on the updated testing of therapeutic efficacy and associated molecular mechanisms of WS extracts and their phytochemicals against SARS-CoV-2 infection in preclinical and clinical studies with the aim to develop a long-term solution against COVID-19. It also deciphered the current use of the in silico molecular docking approach in developing potential inhibitors from WS targeting SARS-CoV-2 and host cell receptors that may aid the development of targeted therapy against SARS-CoV-2 ranging from prior to viral entry until acute respiratory distress syndrome (ARDS). This review also discussed nanoformulations or nanocarriers in achieving effective WS delivery to enhance its bioavailability and therapeutic efficacy, consequently preventing the emergence of drug resistance, and eventually therapeutic failure.

Ashwagandha (Withania somnifera)—Current Research on the Health-Promoting Activities: A Narrative Review

In recent years, there has been a significant surge in reports on the health-promoting benefits of winter cherry (Withania somnifera), also known as Ashwagandha. Its current research covers many aspects of human health, including neuroprotective, sedative and adaptogenic effects and effects on sleep. There are also reports of anti-inflammatory, antimicrobial, cardioprotective and anti-diabetic properties. Furthermore, there are reports of reproductive outcomes and tarcicidal hormone action. This growing body of research on Ashwagandha highlights its potential as a valuable natural remedy for many health concerns. This narrative review delves into the most recent findings and provides a comprehensive overview of the current understanding of ashwagandha’s potential uses and any known safety concerns and contraindications.

Withanolides of Athenaea velutina with potential inhibitory properties against SARS coronavirus main protease (mpro): molecular modeling studies

Since the global COVID-19 pandemic began, the scientific community has dedicated efforts to finding effective antiviral drugs to treat or minimize the effects caused by the SARS-CoV-2 coronavirus. Some targets can act as inhibitor substrates, highlighting the Main Protease (Mpro), which plays an essential role in the translation and transcription of the virus cycle. Withanolides, a class of natural C28 steroidal lactones, are compounds of interest as possible inhibitors of Mpro and other critical targets of the virus, such as papain-like protease. In this study, the isolation of a new withanolide (1), along with the known 27-deoxywithaferin A (2) and 27-deoxy-2,3-dihydrowithaferin A (3), from the leaves of Athenaea velutina (Solanaceae) is described. Their structures were determined using spectroscopic and spectrometric methods (NMR, IR, HRESIMS). Moreover, the interaction and the stability of withanolides 1-3 and withanolide D (4), previously isolated of Acnistus arborescens, against the Mpro target through molecular docking, molecular dynamics, and binding free energy simulations were analyzed. The molecular dynamics results indicated that the complexes formed by the molecular docking simulations between the Mpro target with each of the withanolides 1-4 exhibited good stability during the simulations due to a slight change in the structure of complexes. The binding free energy results suggested that withanolide (1) can be a natural candidate against COVID-19 disease.Communicated by Ramaswamy H. Sarma.

Pharmacological potential of Withania somnifera (L.) Dunal and Tinospora cordifolia (Willd.) Miers on the experimental models of COVID-19, T cell differentiation, and neutrophil functions

Cytokine release syndrome (CRS) due to severe acute respiratory coronavirus-2 (SARS-CoV-2) infection leads to life-threatening pneumonia which has been associated with coronavirus disease (COVID-19) pathologies. Centuries-old Asian traditional medicines such as Withania somnifera (L.) Dunal (WS) and Tinospora cordifolia (Willd.) Miers (TC) possess potent immunomodulatory effects and were used by the AYUSH ministry, in India during the COVID-19 pandemic. In the present study, we investigated WS and TC's anti-viral and immunomodulatory efficacy at the human equivalent doses using suitable in vitro and in vivo models. While both WS and TC showed immuno-modulatory potential, WS showed robust protection against loss in body weight, viral load, and pulmonary pathology in the hamster model of SARS-CoV2. In vitro pretreatment of mice and human neutrophils with WS and TC had no adverse effect on PMA, calcium ionophore, and TRLM-induced ROS generation, phagocytosis, bactericidal activity, and NETs formation. Interestingly, WS significantly suppressed the pro-inflammatory cytokines-induced Th1, Th2, and Th17 differentiation. We also used hACE2 transgenic mice to further investigate the efficacy of WS against acute SARS-CoV2 infection. Prophylactic treatment of WS in the hACE2 mice model showed significant protection against body weight loss, inflammation, and the lung viral load. The results obtained indicate that WS promoted the immunosuppressive environment in the hamster and hACE2 transgenic mice models and limited the worsening of the disease by reducing inflammation, suggesting that WS might be useful against other acute viral infections. The present study thus provides pre-clinical efficacy data to demonstrate a robust protective effect of WS against COVID-19 through its broader immunomodulatory activity.

Identification and structural studies of natural inhibitors against SARS-CoV-2 viral RNA methyltransferase (NSP16)

Pathogenic RNA viruses are emerging as one of the major threats and posing challenges to human community. RNA viruses have an exceptionally shorter generation time and easy to adapt in host cells. The recent emergence of SARS-CoV-2, a long RNA virus, has shown us how difficult it is to overcome this kind of pandemic without understanding the viral infection and replication mechanisms. It is essential to comprehend replications of the viral genome, including RNA polymerization and the final capping process. The mRNAs of SARS-CoV-2 coronaviruses are protected at their 5'-ends by cap structure. The cap-like system plays a significant role in viral translational process, viral RNA stability, and scatting in detecting innate immune recognition in host cells. Two coronavirus enzymes, Nsp14 and Nsp16, critically help in the formation of capping and are considered as potential drug targets for antiviral therapy. Natural and herbal medicines have a past record of treating various acute respiratory diseases. In this work, we have exploited 56000 natural compounds to screen potential inhibitors against NSP16. In silico virtual screening, docking and Molecular Dynamics (MD) simulation studies were performed to understand how these potential inhibitors are bound to NSP16. We observed that the most highly screened compound binds to protein molecules with a high dock score, primarily through hydrophobic interactions and hydrogen bonding, as previously reported for NSP16. Compound-13 (2-hydroxy-N-({1-[2-hydroxy-1-(hydroxymethyl)ethyl]piperidin-3-yl}methyl)-5-methylbenzamide) and compound-51 (N-(2-isobutoxybenzyl)-N,2-dimethyl-2,8-diazaspiro[4.5]decane-3-carboxamide) occupied in active site along with good pharmokinetices properties. In conclusion, the selected compounds could be used as a novel therapeutic against SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

Chantriolides F-P, Highly Oxidized Withanolides with Hepatoprotective Activity from Tacca chantrieri

Eleven highly oxidized withanolides, chantriolides F-P (1-11), together with six known analogues (12-17), were isolated from the rhizomes of Tacca chantrieri. Their structures were established on the basis of comprehensive spectroscopic data analysis and comparison with published NMR data, and their absolute configurations were further confirmed by experimental ECD data and single crystal X-ray diffraction analysis. The structures of compounds 5-8 contained a chlorine atom substituted at C-3. Compounds 1 and 12 are a pair of epimers isomerized at C-24 and C-25, while compounds 9 and 16 are isomerized at C-1, C-7, C-24, and C-25. Next, the hepatoprotective effect of all the isolates was evaluated on tert-butyl hydroperoxide (t-BHP)-injured AML12 hepatocytes. Compounds 5-11 and 16 significantly enhanced cell viability. Compound 8 decreased reactive oxygen species accumulation and increased glutathione level in t-BHP injured AML12 hepatocytes through promoting nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2).

Withania somnifera (L.) Dunal (Ashwagandha) for the possible therapeutics and clinical management of SARS-CoV-2 infection: Plant-based drug discovery and targeted therapy

Coronavirus disease 2019 (COVID-19) pandemic has killed huge populations throughout the world and acts as a high-risk factor for elderly and young immune-suppressed patients. There is a critical need to build up secure, reliable, and efficient drugs against to the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Bioactive compounds of Ashwagandha [Withania somnifera (L.) Dunal] may implicate as herbal medicine for the management and treatment of patients infected by SARS-CoV-2 infection. The aim of the current work is to update the knowledge of SARS-CoV-2 infection and information about the implication of various compounds of medicinal plant Withania somnifera with minimum side effects on the patients' organs. The herbal medicine Withania somnifera has an excellent antiviral activity that could be implicated in the management and treatment of flu and flu-like diseases connected with SARS-CoV-2. The analysis was performed by systematically re-evaluating the published articles related to the infection of SARS-CoV-2 and the herbal medicine Withania somnifera. In the current review, we have provided the important information and data of various bioactive compounds of Withania somnifera such as Withanoside V, Withanone, Somniferine, and some other compounds, which can possibly help in the management and treatment of SARS-CoV-2 infection. Withania somnifera has proved its potential for maintaining immune homeostasis of the body, inflammation regulation, pro-inflammatory cytokines suppression, protection of multiple organs, anti-viral, anti-stress, and anti-hypertensive properties. Withanoside V has the potential to inhibit the main proteases (Mpro) of SARS-CoV-2. At present, synthetic adjuvant vaccines are used against COVID-19. Available information showed the antiviral activity in Withanoside V of Withania somnifera, which may explore as herbal medicine against to SARS-CoV-2 infection after standardization of parameters of drug development and formulation in near future.

Evaluation the Protective Effect of Withania somnifera Extract on the Level of Sex Hormone in Morphine Addicted Female Rats

Morphine is one of the most types of phenanthrene alkaloid opioid used to soothe the acute and chronic pain via narcotic and analgesic medical employment. Increasingly constantly used of opioid in the public and medication practical important knowledge improve that. Morphine show pernicious has effects on numerous tissue for instance ovary, liver and lung morphine side effects instruct for existence of oxidative role due to generation of reactive oxygen species in the affected tissue. Last decades researchers proved that natural substance provides protective role against toxic effect. Thus, withania somnifera consider as antioxidant substance provide protective versus the toxic substance as morphine. The present study wase aimed to evaluate the protective role of withania somnifera extract on the level of sex hormone in morphine addicted female rats. In conclusion, the present study confirmed a truth evidence of a protective roles of withania somnifera  against the morphine addiction in female rats.

Plant-derived active compounds as a potential nucleocapsid protein inhibitor of SARS-CoV-2: an in-silico study

The coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2. This virus has a high mismatch repair proofreading ability due to its unique exonuclease activity, making it knotty to treat. The nucleocapsid protein can serve as a potential antiviral drug target, as this protein is responsible for multiple captious functions during the viral life cycle. Herein, we have investigated the potential to repurpose active antiviral compounds of plant origins for treating the SARS-CoV-2 infection. In the present study, we followed the molecular docking methodology to screen druggable natural plants' active compounds against the nucleocapsid protein of SARS-CoV-2. The virtual screening of all 68 compounds revealed that the top seven active compounds, such as withanolide D, hypericin, silymarin, oxyacanthine, withaferin A, Acetyl aleuritolic acid, and rhein, exhibit good binding affinity with druggable ADME properties, toxicity, and Pass prediction. The stability of the docked complexes was studied by conducting molecular simulations of 100 ns. MM-GBSA calculated the binding free energy uncovered that withanolide D, hypericin, and silymarin result in highly stable binding conformations in three different sites of the nucleocapsid protein. However, further investigation is needed in order to validate the candidacy of these inhibitors for clinical trials. HighlightsNatural plants' active compounds may aid in the inhibition of SARS-CoV-2 replication and COVID-19 therapeutics.Hypericin, silymarin, withanolide D, oxyacanthine, withaferin A, Acetyl aleuritolic acid, and rhein are effective against SARS-CoV-2 N protein.Studied natural plants' active compounds could be useful against COVID-19 and its associated organs comorbidities.ADMET properties of selected compounds favor these compounds as druggable candidates.Communicated by Ramaswamy H. Sarma.

3β-Acetoxy-21α-H-hop-22(29)ene, a novel multitargeted phytocompound against SARS-CoV-2: in silico screening

The present pandemic disease COVID-19 demands an urgent need for more efficient antiviral drugs against SARS-CoV-2. Computational drug designing and discovery enable us to explore ethnomedicinal plants as a source of various lead molecules that can be used against present and future pathogens. Adiantum latifolium Lam., a common fern, is resistant to pathogens mainly due to the presence of various phytochemicals having antimicrobial properties. In our previous study, 3β-acetoxy-21α-H-hop-22(29)ene, a terpenoid has been characterized from the methanol extract of leaves of A. latifolium. The manuscript evaluates the antiviral potency of the compound against SARS-CoV-2 through molecular docking method. Proteins essential for SARS-CoV-2 multiplication in host cells are the target sites. The study revealed strong binding affinity of the compound for all the ten proteins selected, including seven nonstructural proteins, two structural proteins and one receptor protein, with a binding energy of -4.67 to -8.76 kcal/mol. MDS and MMPBSA analysis of the best ranked complex further confirmed the results. The multitargeted compound can be considered as a natural lead molecule in drug designing against COVID-19, but requires wet-lab experimentation and clinical trials.Communicated by Ramaswamy H. Sarma.

Withania somnifera: Progress towards a Pharmaceutical Agent for Immunomodulation and Cancer Therapeutics

Chemotherapy is one of the prime treatment options for cancer. However, the key issues with traditional chemotherapy are recurrence of cancer, development of resistance to chemotherapeutic agents, affordability, late-stage detection, serious health consequences, and inaccessibility. Hence, there is an urgent need to find innovative and cost-effective therapies that can target multiple gene products with minimal adverse reactions. Natural phytochemicals originating from plants constitute a significant proportion of the possible therapeutic agents. In this article, we reviewed the advances and the potential of Withania somnifera (WS) as an anticancer and immunomodulatory molecule. Several preclinical studies have shown the potential of WS to prevent or slow the progression of cancer originating from various organs such as the liver, cervix, breast, brain, colon, skin, lung, and prostate. WS extracts act via various pathways and provide optimum effectiveness against drug resistance in cancer. However, stability, bioavailability, and target specificity are major obstacles in combination therapy and have limited their application. The novel nanotechnology approaches enable solubility, stability, absorption, protection from premature degradation in the body, and increased circulation time and invariably results in a high differential uptake efficiency in the phytochemical’s target cells. The present review primarily emphasizes the insights of WS source, chemistry, and the molecular pathways involved in tumor regression, as well as developments achieved in the delivery of WS for cancer therapy using nanotechnology. This review substantiates WS as a potential immunomodulatory, anticancer, and chemopreventive agent and highlights its potential use in cancer treatment.

System biology-based investigation of Silymarin to trace hepatoprotective effect

Silymarin is used as a hepatoprotective agent since ancient times which could be via its potent anti-oxidant effect. However, the mode of silymarin for the hepatoprotective effect has not been established with the targets involved in hepatic cirrhosis. The present study investigated the multiple interactions of the flavonolignans from Silybum marianum with targets involved in hepatic cirrhosis using a series of system biology approaches. Chemo-informative tools and databases i.e. DIGEP-Pred and DisGeNET were used to predict the targets of flavonolignans and proteins involved in liver cirrhosis respectively. Further, STRING was used to enrich the protein-protein interaction for the flavonolignans-modulated targets. Similarly, molecular docking was performed using AutoDock Vina. Additionally, molecular dynamics simulation and MM-PBSA calculations were carried out for the lead-hit complexes by GROMACS. Thirteen flavonolignans were identified from S. marianum, in which silymonin exhibited the highest drug-likeness score i.e. 1.09. Similarly, CTNNB1 was found to be regulated by the 12 different flavonolignans and was majorly expressed within the compound(s)-protein(s)-pathway(s) network. Further, silymonin had the highest binding affinity; binding energy -9.2 kcal/mol with the CTNNB1 and formed very stable hydrogen bond interactions with Arg332, Ser336, Lys371, and Arg475 throughout 100 ns molecular dynamic production run. The binding free energy of CTNNB1-silymonin complex was found to be -15.83 ± 2.71 kcal/mol. The hepatoprotective property of S. marianum may be due to the presence of silymonin and silychristin; this could majorly modulate CTNNB1, HMOX1, and CASP8 in combination with other flavonolignans. Our findings further suggest designing the in-vitro and in-vivo studies to validate the interaction of flavonolignans with identified targets to strengthen present findings of S. marianum as a hepatoprotective..

Perspectives on nano-nutraceuticals to manage pre and post COVID-19 infections

Optimized therapeutic bio-compounds supported by bio-acceptable nanosystems (i.e., precise nanomedicine) have ability to promote health via maintaining body structure, organ function, and controlling chronic and acute effects. Therefore, nano-nutraceuticals (designed to neutralize virus, inhibit virus bindings with receptors, and support immunity) utilization can manage COVID-19 pre/post-infection effects. To explore these approaches well, our mini-review explores optimized bio-active compounds, their ability to influence SARS-CoV-2 infection, improvement in performance supported by precise nanomedicine approach, and challenges along with prospects. Such optimized pharmacologically relevant therapeutic cargo not only affect SARS-CoV-2 but will support other organs which show functional alternation due to SARS-CoV-2 for example, neurological functions. Hence, coupling the nutraceuticals with the nano-pharmacology perspective of higher efficacy via targeted delivery action can pave a novel way for health experts to plan future research needed to manage post COVID-19 infection effect where a longer efficacy with no side-effects is a key requirement.

Insights into the potential of withanolides as Phosphodiesterase-4 (PDE4D) inhibitors

Medicinal herbs have been used as traditional medicines for centuries. The molecular mechanism of action of their bioactive molecules against various diseases or therapeutic targets is still being explored. Here, the active compounds (withanolides) of a well-known Indian medicinal herb, Ashwagandha (Withania somnifera), have been studied for their most potential therapeutic targets and their mechanism of action using ligand-based screening and receptor-based approaches. Ligand-based screening predicted the six top therapeutic targets, namely, Protein kinase C alpha (PRKCA), Protein kinase C delta (PRKCD), Protein kinase C epsilon (PRKCE), Androgenic Receptor (AR), Cycloxygenase-2 (PTGS-2) and Phosphodiesterase-4D (PDE4D). Further, when these predictions were validated using receptor-based studies, i.e. molecular docking, molecular dynamics simulation and free energy calculations, it was found that PDE4D was the most potent target for four withanolides, namely, Withaferin-A, 17-Hydroxywithaferin-A, 27-Hydroxywithanone and Withanolide-R. These compounds had a better binding affinity and similar interactions as that of an already known inhibitor (Zardaverine) of PDE4D. These results warrant further in-vitro and in-vivo investigations to examine their therapeutic potential as an inhibitor of PDE4D.Communicated by Ramaswamy H. Sarma.

Ayurveda Rasayana as antivirals and immunomodulators: potential applications in COVID-19

Coronavirus disease (COVID-19) has been declared as a pandemic by the World Health Organization with rapid spread across 216 countries. COVID-19 pandemic has left its imprints on various health systems globally and caused immense social and economic disruptions. The scientific community across the globe is in a quest for digging the effective treatment for COVID-19 and exploring potential leads from traditional systems of healthcare across the world too. Ayurveda (Indian traditional system of medicine) has a comprehensive aspect of immunity through Rasayana which is a rejuvenation therapy. Here we attempt to generate the potential leads based on the classical text from Ayurveda in general and Rasayana in particular to develop effective antiviral and/or immunomodulator for potential or adjunct therapy in SARS-CoV-2. The Rasayana acts not only by resisting body to restrain or withstand the strength, severity or progression of a disease but also by promoting power of the body to prevent the manifestation of a disease. These Rasayana herbs are common in practice as immunomodulator, antiviral and protectives. The studies on Rasayana can provide an insight into the future course of research for the plausible development of effective management of COVID-19 by the utilization and development of various traditional systems of healthcare. Keeping in view the current pandemic situation, there is an urgent need of developing potential medicines. This study proposes certain prominent medicinal plants which may be further studied for drug development process and also in clinical setup under repurposing of these herbs.

In Silico Evaluation of Iranian Medicinal Plant Phytoconstituents as Inhibitors against Main Protease and the Receptor-Binding Domain of SARS-CoV-2

The novel coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initially appeared in Wuhan, China, in December 2019. Elderly individuals and those with comorbid conditions may be more vulnerable to this disease. Consequently, several research laboratories continue to focus on developing drugs to treat this infection because this disease has developed into a global pandemic with an extremely limited number of specific treatments available. Natural herbal remedies have long been used to treat illnesses in a variety of cultures. Modern medicine has achieved success due to the effectiveness of traditional medicines, which are derived from medicinal plants. The objective of this study was to determine whether components of natural origin from Iranian medicinal plants have an antiviral effect that can prevent humans from this coronavirus infection using the most reliable molecular docking method; in our case, we focused on the main protease (Mpro) and a receptor-binding domain (RBD). The results of molecular docking showed that among 169 molecules of natural origin from common Iranian medicinal plants, 20 molecules (chelidimerine, rutin, fumariline, catechin gallate, adlumidine, astragalin, somniferine, etc.) can be proposed as inhibitors against this coronavirus based on the binding free energy and type of interactions between these molecules and the studied proteins. Moreover, a molecular dynamics simulation study revealed that the chelidimerine-Mpro and somniferine-RBD complexes were stable for up to 50 ns below 0.5 nm. Our results provide valuable insights into this mechanism, which sheds light on future structure-based designs of high-potency inhibitors for SARS-CoV-2.

Computational and network pharmacology studies of Phyllanthus emblica to tackle SARS-CoV-2

Background

Since December 2019, SARS-CoV-2 had been a significant threat globally, which has accounted for about two million deaths. Several types of research are undergoing and have reported the significant role of repurposing existing drugs and natural lead in the treatment of COVID-19. The plant Phyllanthus emblica (Synonym-Emblica officinalis) (Euphorbiaceae) is a rich source of vitamin C, and its use as an antiviral agent has been well established.

Purpose

The present study was undertaken to investigate the potency of the several components of Phyllanthus emblica against three protein targets of 2019-nCoV viz. NSP15 endoribonuclease, main protease, and receptor binding domain of prefusion spike protein using molecular docking and dynamics studies.

Methods

The docking simulation studies were carried out using Schrödinger maestro 2018-1 MM share version, while dynamics studies were conducted to understand the binding mechanism and the complexes' stability studies.

Results

Out of sixty-six tested compounds, Chlorogenic acid, Quercitrin, and Myricetin were most effective in showing the highest binding energy against selected protein targets of SARS-CoV-2. The network pharmacology analysis study confirmed these compounds' role in modulating the immune response, inflammatory cascade, and cytokine storm through different signaling pathways.

Conclusion

Current pharmacoinformatic approach shows possible role of Phyllanthus emblica in the treatment and management of COVID-19.

Gene set enrichment analysis of PPAR-γ regulators from Murraya odorata Blanco

BACKGROUND

Peroxisome proliferator-activated receptor gamma (PPAR-γ) is reported to regulate insulin sensitivity and progression of Type 2 diabetes mellitus (T2DM). Hence the present study is aimed to identify PPAR-γ regulators from Murraya odorata Blanco and predict their role to manage T2DM.

METHODS

Multiple in-silico tools and databases like SwissTargetPrediction, ADVERPred, PubChem, and MolSoft, were used to retrieve the information related to bioactives, targets, druglikeness character, and probable side effects as applicable. Similarly, the Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used to identify the regulated pathways. Further, the bioactives-protein-pathways network interaction was constructed using Cytoscape. Finally, molecular docking was performed using Autodock4.

RESULTS

Twenty-five bioactives were shortlisted in which six were predicted as PPAR-γ modulators. Among them, stigmasterol was predicted to possess the best binding affinity towards PPAR-γ and possessed no side effects. Similarly, n-hexadecanoic acid was predicted to modulate the highest number of proteins, and protein CD14 was targeted by the highest number of bioactives. Further, the PI3K-Akt pathway was predicted as the maximum modulated genes.

CONCLUSIONS

The anti-diabetic property of the Murraya odorata Blanco of fruit pulp may be due to the presence of n-hexadecanoic acid and stigmasterol; may also involve in the regulation of the PI3K-Akt pathway which needs further investigated by in-vitro and in-vivo protocols.

Rac1, A Potential Target for Tumor Therapy

RAS-related C3 botulinum toxin substrate 1 (Rac.1) is one of the important members of Rho GTPases. It is well known that Rac1 is a cytoskeleton regulation protein that regulates cell adhesion, morphology, and movement. Rac1 is highly expressed in different types of tumors, which is related to poor prognosis. Studies have shown that Rac1 not only participates in the tumor cell cycle, apoptosis, proliferation, invasion, migration and angiogenesis, but also participates in the regulation of tumor stem cell, thus promoting the occurrence of tumors. Rac1 also plays a key role in anti-tumor therapy and participates in immune escape mediated by the tumor microenvironment. In addition, the good prospects of Rac1 inhibitors in cancer prevention and treatment are exciting. Therefore, Rac1 is considered as a potential target for the prevention and treatment of cancer. The necessity and importance of Rac1 are obvious, but it still needs further study.

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.

Identification of PTP1B regulators from Cymbopogon citratus and its enrichment analysis for diabetes mellitus

PTP1B is identified as the insulin signaling pathway downregulator; involved in pancreatic β-cell apoptosis. Further, it associates in regulating multiple pathways in diabetes mellitus; kindled us to identify the binding affinity of bioactives from Cymbopogon citratus by targeting PTP1B and identify the probably associated with it; further identifying the probable pathways involved in diabetes mellitus. In this regard, ChEBI database was used to retrieve bio-actives from C. citrates and 3D structures for the same were obtained from the PubChem database. The energy of bioactives was minimized and converted into ligand and the docking was carried using autodock 4.0 against PTP1B. Further, multiple characters of bio-actives like drug-likeness score, ADMET profile, probable adverse effects, and boiled egg model for bioavailability were also studied. Swertiajaponin was predicted for the highest drug-likeness score i.e. 0.26. However, swertiajaponin was predicted with the highest probable side effect of nephrotoxicity with pharmacological activity of 0.478. Similarly, swertiajaponin was predicted for the highest binding affinity with PTP1B with the binding energy of - 8.3 kcal/mol. Likewise, KEGG identified 80 pathways associated with PTP1B modulation in which 7 pathways were involved in diabetes mellitus in which FoxO signaling pathway was predicted to have the least false discovery rate by modulating 7 genes. Swertiajaponin could act as the potent inhibitor of PTP1B; scored highest druglikeness score but possessed minimum GIT absorptivity; further, PTP1B was identified to be linked with multiple pathways that are concerned with diabetes mellitus.

Screening of JAK-STAT modulators from the antiviral plants of Indian traditional system of medicine with the potential to inhibit 2019 novel coronavirus using network pharmacology

The majority of the bioactives under investigation were predicted to target TNF receptor-associated factor 5 in the Janus kinase/signal transducers and activators of the transcription pathway. Similarly, druglikeness prediction identified vitexilactone to possess the highest druglikeness score, i.e., 0.88. Furthermore, proteins targeted in the Janus kinase/signal transducers and activators of transcription pathway were also predicted to regulate multiple pathways, i.e., ErbB, AGE-RAGE, NF-kappa B, Measles, insulin, mTOR, chemokine, Ras, and pathways associated with infectious and non-infectious pathogenesis, where the immune system is compromised. Similarly, the docking study identified sesaminol 2-O-β-D-gentiobioside to possess the highest binding affinity with 3CLpro, PLpro, and spike proteins. Furthermore, phylogeny comparison identified the common protein domains with other stains of microbes like murine hepatitis virus strain A59, avian infectious bronchitis virus, and porcine epidemic diarrhea virus CV777.

Combination of system biology to probe the anti-viral activity of andrographolide and its derivative against COVID-19

The present study aimed to investigate the binding affinity of andrographolide and its derivative i.e., 14-deoxy-11,12-didehydroandrographolide with targets related to COVID-19 and their probable role in regulating multiple pathways in COVID-19 infection. SMILES of both compounds were retrieved from the PubChem database and predicted for probably regulated proteins. The predicted proteins were queried in STRING to evaluate the protein-protein interaction, and modulated pathways were identified concerning the KEGG database. Drug-likeness and ADMET profile of each compound was evaluated using MolSoft and admetSAR 2.0, respectively. Molecular docking was carried using Autodock 4.0. Andrographolide and its derivative were predicted to have a high binding affinity with papain-like protease, coronavirus main proteinase, and spike protein. Molecular dynamics simulation studies were performed for each complex which suggested the strong binding affinities of both compounds with targets. Network pharmacology analysis revealed that both compounds modulated the immune system by regulating chemokine signaling, Rap1 signaling, cytokine-cytokine receptor interaction, MAPK signaling, NF-kappa B signaling, RAS signaling, p53 signaling, HIF-1 signaling, and natural killer cell-mediated cytotoxicity. The study suggests strong interaction of andrographolide and 14-deoxy-11,12-didehydroandrographolide against COVID-19 associated target proteins and exhibited different immunoregulatory pathways.