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

Synthesis of novel (R)-carvone-tagged thiazolidinone as anticancer leads: characterization, in vitro antiproliferative evaluation and in silico studies

This work describes the successful synthesis of a series of three novel thiazolidinone-carvone-O-alkyl hybrids through a two-step approach involving heterocyclization and O-alkylation reactions. Comprehensive structural characterization of the obtained products was achieved using NMR and HRMS spectroscopic techniques. This study assessed in vitro antiproliferative activity of synthesized thiazolidinone-carvone-O-alkyl hybrids (5a-c) against various human cancer cell lines, viz. HT-1080 (fibrosarcoma), A-549 (lung cancer), MCF-7 (breast cancer) and MDA-MB-231 (breast cancer). MTT assay revealed promising results for compounds 5b and 5c, demonstrating good antiproliferative activity against A-549 and MCF-7 cell lines comparable to the positive control, Doxorubicin. Compound 5a, harbouring an O-acetoxy group, displayed limited anticancer activity against MCF-7 and MDA-MB-231 cells, with IC50 values of 69.33 ± 0.42 µM and >100 µM, respectively. Docking results confirmed that the compounds 5a-c binds at the active site of p21 with docking scores -2.0, -4.8, and -7.0 kcal/mol, respectively. Compound 5a-c also showed good binding potential against Bcl2 protein with docking score of -4.9, -6.0, -5.5 kcal/mol, respectively. Furthermore, binding energy analysis and dynamics simulation studies of compounds towards p21 and Bcl2 yielded promising results. In PAK4 assay, compound 5c showed comparable potency (IC50 6.76 µM) with the standard control UC2288 (IC50 6.40 µM), while in BCL-2 TR-FRET assay, 5c exhibited good inhibition (IC50 1.78 µM) as compared to Venetoclax (IC50 0.016 µM). In conclusion, compounds 5a-c could be used as a structural framework for the discovery of novel therapeutics to combat different types of cancer.Communicated by Ramaswamy H. Sarma.

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.

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.