Phytochemical characterization, biochemical profiling and evaluation of anticancer potential of methanolic extract of Withania somnifera stem.

OBJECTIVES: Phytotherapy employs phytoconstituents/phytomedicines derived from plants for treating and preventing illnesses. Withania somnifera is known in the Indian Ayurveda Pharmacopoeia for its medicinal applications and pharmacological properties. In this study, we examined the biological activity spectrum of Withania somnifera methanolic extract of stem (WSME), which is valued as a "Rasayana" due to its extensive range of medicinal uses. METHODS: WSME was subjected to TPC and TFC quantification and bioactive components were characterized using LC-MS. Its antioxidant potential was gauged by DPPH and H2O2 radical scavenging assays, while antibacterial efficacy was assessed against S. aureus and E. coli using disc diffusion assay. In vitro anticancer activity was evaluated against human breast cancer MDA-MB-231 cells while toxicity was evaluated against normal Vero cells using MTT assay. RESULTS: WSME, rich in Withaferin A, showed TPC of 4.73 ± 0.15 mg GAE/g and TFC of 94.94 ± 6.15 mg QE/g dry weight of extract. It exhibited significant antioxidant activity (43.28 and 66.8 % inhibition at 1,000 µg/mL using DPPH and H2O2 assays, respectively) and mild antibacterial effects against S. aureus (300-500 mg/mL). WSME induced cell death in MDA-MB-231 cells and significantly inhibited their growth (IC50: 66 µg/mL, P value<0.05) without affecting normal Vero cells in the studied range of 25-400 µg/mL (IC50: 6.09 mg/mL, P value>0.05). CONCLUSIONS: The present study lends support to further testing of WSME against other cancer cell lines and animal models of cancer. These preclinical studies would provide further validation to its prospective use as an adjunct in human breast cancer therapy.

An update on existing therapeutic options and status of novel anti-metastatic agents in breast cancer: Elucidating the molecular mechanisms underlying the pleiotropic action of Withania somnifera (Indian ginseng) in breast cancer attenuation.

Major significant advancements in pharmacology and drug technology have been made to heighten the impact of cancer therapies, improving the life expectancy of subjects diagnosed with malignancy. Statistically, 99% of breast cancers occur in women while 0.5-1% occur in men, the female gender being the strongest breast cancer risk factor. Despite several breakthroughs, breast cancer continues to have a worldwide impact and is one of the leading causes of mortality. Additionally, resistance to therapy is a crucial factor enabling cancer cell persistence and resurgence. As a result, the search and discovery of novel modulatory agents and effective therapies capable of controlling tumor progression and cancer cell proliferation is critical. Withania somnifera (L.) Dunal (WS), commonly known as Indian ginseng, has long been used traditionally for the treatment of several ailments in the Indian context. Recently, WS and its phytoconstituents have shown promising anti-breast cancer properties and, as such, can be employed as prophylactic as well as therapeutic adjuncts to the main line of breast cancer treatment. The present review is an attempt to explore and provide experimental evidences in support of the prophylactic and therapeutic potential of WS in breast cancer, along with a deeper insight into the multiple molecular mechanisms and novel targets through which it acts against breast and other hormonally-induced cancers viz. ovarian, uterine and cervical. This exploration might prove crucial in providing better understanding of breast cancer progression and metastasis and its use as an adjunct in improving disease prognosis and therapeutic outcome.

Structural interactions of phytoconstituent(s) from cinnamon, bay leaf, oregano, and parsley with SARS-CoV-2 nucleocapsid protein: A comparative assessment for development of potential antiviral nutraceuticals.

SARS-CoV-2 has been responsible for causing 6,218,308 deaths globally till date and has garnered worldwide attention. The lack of effective preventive and therapeutic drugs against SARS-CoV-2 has further worsened the scenario and has bolstered research in the area. The N-terminal and C-terminal RNA binding domains (NTD and CTD) of SARS-CoV-2 nucleocapsid protein represent attractive therapeutic drug targets. Naturally occurring compounds are an excellent source of novel drug candidates due to their structural diversity and safety. Ten major bioactive compounds were identified in ethanolic extract (s) of Cinnamomum zeylanicum, Cinnamomum tamala, Origanum vulgare, and Petroselinum crispum using HPLC and their cytotoxic potential was determined against cancer and normal cell lines by MTT assay to ascertain their biological activity in vitro. To evaluate their antiviral potential, the binding efficacy to NTD and CTD of SARS-CoV-2 nucleocapsid protein was determined using in silico biology tools. In silico assessment of the phytocomponents revealed that most of the phytoconstituents displayed a druglike character with no predicted toxicity. Binding affinities were in the order apigenin > catechin > apiin toward SARS-CoV-2 nucleocapsid NTD. Toward nucleocapsid CTD, the affinity decreased as apigenin > cinnamic acid > catechin. Remdesivir displayed lesser affinity with NTD and CTD of SARS-CoV-2 nucleocapsid proteins than any of the studied phytoconstituents. Molecular dynamics (MD) simulation results revealed that throughout the 100 ns simulation, SARS-CoV-2 nucleocapsid protein NTD-apigenin complex displayed greater stability than SARS-CoV-2 nucleocapsid protein NTD-cinnamic acid complex. Hence, apigenin, catechin, apiin and cinnamic acid might prove as effective prophylactic and therapeutic candidates against SARS-CoV-2, if examined further in vitro and in vivo. PRACTICAL APPLICATIONS: Ten major bioactive compounds were identified in the extract(s) of four medicinally important plants viz. Cinnamomum zeylanicum, Cinnamomum tamala, Origanum vulgare and Petroselinum crispum using HPLC and their biological activity was also evaluated against cancer and normal cell lines. Interestingly, while all extract(s) wielded significant cytotoxicity against cancer cells, no significant toxicity was found against normal cells. The outcome of the results prompted evaluation of the antiviral potential of the ten bioactive compounds using in silico biology tools. The present study emphasizes on the application of computational approaches to understand the binding interaction and efficacy of the ten bioactive compounds from the above plants with SARS-CoV-2 nucleocapsid protein N-terminal and C-terminal RNA binding domains in preventing and/or treating COVID-19 using in silico tools. Druglikeness and toxicity profiles of the compounds were carried out to check the therapeutic application of the components. Additionally, molecular dynamics (MD) simulation was performed to check the stability of ligand-protein complexes. The results provided useful insights into the structural binding interaction(s) that can be exploited for the further development of potential antiviral agents targeting SARS-CoV-2 especially since no specific therapy is still available to combat the rapidly evolving virus and the existing treatment is more or less symptomatic which makes search for novel antiviral agents all the more necessary and crucial.

Effects of tert-butyl hydroperoxide on Ca(2+) ATPase activity in isolated rat hepatocytes and its reversal by antioxidants.

Calcium ions play an importantrole in various physiological processes such as nerve impulse transmission, muscle contraction, hormone action, blood clotting. They ions act as an intracellular second messenger, relaying information within cells to regulate their activity. To understand the mechanism of hepatotoxicity of t-BHP, studies were carried out using freshly isolated rat hepatocytes. The effect of t-BHP on Ca(2+) accumulation and Ca(2+) uptake by rat hepatocytes was monitored using 45Ca(2+). It caused decrease in 15% accumulation of 45Ca(2+) in comparison to the control group. t-BHP also significantly decreased the Ca(2+) ATPase activity in isolated hepatocytes .This decrease in Ca(2+) ATPase activity by t-BHP was reversed 40% by naturally occurring antioxidant glutathione (GSH) and 20% by the synthetic antioxidant butylated hydroxy toluene (BHT). These results indicate that the hepatotoxic action of t-BHP involves oxidative stress as evident by the protection accorded by various antioxidants employed in the study as well as impairment of intracellular calcium homeostasis which can lead to liver cell injury.