Evaluation of the bioavailability of major withanolides of Withania somnifera using an in vitro absorption model system

Optimized medium composition in Physalis alkekengi callus culture altered nitric oxide level for inducing antioxidant enzyme activities and secondary metabolites

Physalis alkekengi L. is a valuable medicinal plant from the Solanaceae family and has multiple therapeutic applications. This study aimed to develop an optimized protocol for callogenesis in P. alkekengi to obtain friable calluses with high biomass. The effect of different concentrations of picloram, casein hydrolysate (CH), basal media (Murashige and Skoog (MS) and Gamborg (B5)), and static magnetic field (SMF) were investigated on the callus induction and growth, signaling molecules, and enzymatic and non-enzymatic antioxidants. Results showed that CH (200 mgL-1) and SMF4 mT for 90 min increased callus induction and fresh weight in P. alkekengi, while different concentrations of picloram reduced callogenesis. Hypocotyl explants showed various callogenesis and metabolic responses depending on the basal medium type. The 2B5 medium supplied with CH 200 (mgL-1) induced friable and cream calluses with high biomass (0.62 g) compared to the MS medium (control). The maximum activity of superoxide dismutase and catalase activities was identified in the 2B5 medium and peroxidase in the 2MS medium. The highest total phenolic (129.44 µg g-1DW) content and phenylalanine-ammonia lyase activity were obtained in the 2MS medium, and total withanolides (49.86 µg g-1DW) and DPPH radical scavenging activity were observed in the 2B5 medium. The 2MS medium boosted the hydrogen peroxide and nitric oxide levels, while their contents alleviated in the 2B5 medium, although these parameters were higher than the control. The findings of this study suggest that an effective protocol for successful callogenesis in P. alkekengi and the nutrient composition of culture medium by affecting the level of signaling molecules can control the antioxidant defense system and callus growth.

Establishment of Physalis alkekengi cell suspension culture: time-dependent behavior of genes related to the steroidal compounds, key enzymes, and physalins under static magnetic field

Cell suspension culture has the potential to be a valuable source for the bioactive compound productions. In this study, an optimized procedure was established for callus and cell suspension culture of Physalis alkekengi for the first time, and the impact of static magnetic field (SMF, 6 mT) was studied on the high-value metabolic compounds through investigation of signaling molecules and gene expressions at the late log-to-stationary phase. Results showed that the growth regulators of 6-benzyl amino purine (BAP, 1.5 mg-1 L) and 1-naphthaleneacetic acid (NAA, 0.4 mg-1 L) induced the highest fresh weight, callus rate, callus index, and total withanolides. Cell suspension culture was established in the liquid MS medium supplied with BAP (1.5 mg-1 L) and NAA (0.1 mg-1 L). SMF application decreased slightly the cell growth and viability and enhanced the number of round-shaped cells. The hydrogen peroxide (H2O2) and nitric oxide (NO) levels increased at an all-time series after SMF exposure, and their maximum contents were observed after 12 h. A significant alteration of malondialdehyde content was also identified after 12 h of SMF exposure. The expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), 1-deoxyD-xylulose 5-phosphate synthase (DXS), squalene synthase (SQS), sterol Δ7-reductase (DWF5), and C-7,8 sterol isomerase (HYD1) genes was upregulated significantly after 24 and 48 h. An increase in the total withanolides was related to more activity of HMGR and DXS enzymes in SMF-exposed cells and the maximum physalin A (12.8 mg g-1 DW) and physalin B (1.92 mg g-1 DW) obtained after 24 h compared to controls. Findings suggest that SMF can play a supportive factor in inducing steroidal compounds in P. alkekengi through modulating H2O2 and NO levels and the related-gene expressions.

The Potential Pharmacological Effects of Natural Product Withaferin A in Cancer: Opportunities and Challenges for Clinical Translation

Cancer is one of the biggest health concerns with a complex pathophysiology. Currently, available chemotherapeutic drugs are showing deleterious side effects, and tumors often show resistance to treatment. Hence, extensive research is required to develop new treatment strategies to fight against cancer. Natural resources from plants are at the forefront of hunting novel drugs to treat various types of cancers. Withaferin A (WA) is a naturally occurring withanolide, a biologically active component obtained from the plant Ashwagandha. Various in vitro and in vivo oncological studies have reported that Withaferin A (WA) has shown protection from cancer. WA shows its activity by inhibiting the growth and proliferation of malignant cells, apoptosis, and inhibiting angiogenesis, metastasis, and cancer stem cells (CSCs). In addition, WA also showed chemo- and radio-sensitizing properties. Besides the beneficiary pharmacological activities of WA, a few aspects like pharmacokinetic properties, safety, and toxicity studies are still lacking, hindering this potent natural product from entering clinical development. In this review, we have summarized the various pharmacological mechanisms shown by WA in in vitro and in vivo cancer studies and the challenges that must be overcome for this potential natural product's clinical translation to be effective.

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.

Withanolides: Promising candidates for cancer therapy

Natural products have played a significant role throughout history in the prevention and treatment of numerous diseases, particularly cancers. As a natural product primarily derived from various medicinal plants in the Withania genus, withanolides have been shown in several studies to exhibit potential activities in cancer treatment. Consequently, understanding the molecular mechanism of withanolides could herald the discovery of new anticancer agents. Withanolides have been studied widely, especially in the last 20 years, and attracted the attention of numerous researchers. Currently, over 1200 withanolides have been classified, with approximately a quarter of them having been reported in the literature to be able to modulate the survival and death of cancer cells through multiple avenues. To what extent, though, has the anticancer effects of these compounds been studied? How far are they from being developed into clinical drugs? What are their potential, characteristic features, and challenges? In this review, we elaborate on the current knowledge of natural compounds belonging to this class and provide an overview of their natural sources, anticancer activity, mechanism of action, molecular targets, and implications for anticancer drug research. In addition, direct targets and clinical research to guide the design and implementation of future preclinical and clinical studies to accelerate the application of withanolides have been highlighted.

Pharmacokinetics and bioequivalence of Withania somnifera (Ashwagandha) extracts - A double blind, crossover study in healthy adults

Introduction

Withania somnifera (WS) or ashwagandha is an adaptogenic plant used extensively in traditional medicines and as a food supplement. Despite a long history of use and numerous clinical trials, the human pharmacokinetics of withanolides, the active phytochemicals in WS extracts, have not been fully evaluated. This study evaluated the oral pharmacokinetics and bioequivalence of active withanolides in human plasma after administration of a single dose of two commercial ashwagandha extracts containing equal amounts of total withanolides.

Methods

This randomized, double-blind, single-dose crossover study of 16 healthy human volunteers evaluated the acute oral bioavailability of withanolides and the bioequivalence of two WS extracts, WS-35 and WS-2.5. WS-35 was standardized to total withanolides not less than 40% comprising not less than 35% withanolide glycosides and WS-2.5 was standardized to 2.5% withanolides. The clinical dosages were normalized to 185 mg of total withanolide in each extract at the bioequivalent dosages. The pharmacokinetic parameters of withanolide A, withanoside IV, withaferin A, and total withanolides were quantified in the blood plasma using a validated LC-MS/MS method.

Results

The half-life, C-max, and mean residence time of the total withanolides were 5.18, 5.62 and 4.13 times significantly higher and had lower systemic clearance with WS-35 than with WS-2.5 extract. Considering the plasma AUC 0-inf of total withanolides per mg of each WS extract administered orally, WS-35 was 280.74 times more bioavailable than WS-2.5.

Conclusion

The results of this study highlight the importance of withanolide glycosides in improving the pharmacokinetics of WS extracts. Owing to its superior pharmacokinetic profile, WS-35, with 35% withanolide glycosides, is a promising candidate for further studies on Withania somnifera.

Clinical trial registration

CTRI/2020/10/028397 [registered on:13/10/2020] (Trial prospectively registered) http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=42149&EncHid=&userName=CTRI/2020/10/028397.

AS1411 aptamer tagged PEGylated liposomes as a smart nanocarrier for tumor-specific delivery of Withaferin A for mitigating pulmonary metastasis

Metastasis is the most challenging health problem contributing to about 90 % of cancer-related deaths worldwide. Metastatic tumors are highly aggressive and resistant to the most available therapeutic options. Hence, innovative therapeutic approaches are required to target metastatic tumors selectively. In this study, we prepared AS1411 functionalized Withaferin A loaded PEGylated nanoliposomes (ALW) and investigated its therapeutic effect in B16F10 induced in pulmonary metastasis mice models. The prepared formulations' size and morphological properties were evaluated using dynamic light scattering system and Transmission electron microscope. ALW had spherical-shaped nanosized particles with a size of 118 nm and an encapsulation efficacy of 82.5 %. TEM analysis data indicated that ALW has excellent dispersibility and uniform spherical nano-size particles. ALW inhibited cell viability, and induced cell apoptosis of B16F10. In vivo, the pulmonary metastasis study in C57BL/6 mice revealed that the ALW significantly (p < 0.01) improved the encapsulated WA anti-metastatic activity and survival rate compared to WA or LW treated groups. ALW significantly (p < 0.01) downregulated the levels of IL-6, TNF-α, and IL-1β and significantly reduced the lung collagen hydroxyproline, hexosamine, and uronic acid content in metastatic tumor bearing animals compared to WA or LW. Gene expression levels of MMPs and NF-κB were downregulated in ALW treated metastatic pulmonary tumor-bearing mice. These findings demonstrate that the AS1411 functionalized Withaferin A loaded PEGylated nanoliposomes could be a promising nanoliposomal formulation for targeting metastatic tumors.

Potential Therapeutic Agents on Alzheimer's Disease through Molecular Docking and Molecular Dynamics Simulation Study of Plant-Based Compounds

Globally Alzheimer's disease (AD) is a highly complex, heterogeneous, and multifactorial neurological disease. AD is categorized clinically through a steady loss in memory and progressive decline of cognitive function. So far, there is no effective cure is available for the treatment of AD. Here, we identified Plant-based compounds (PBCs) from seven therapeutic plants through pharmacophore and pharmacokinetics approaches. Subsequently, we retrieved 65 AD associated proteins by Text Mining approach .We observed the interactions between 39 PBCs with 65 AD-associated targets by using molecular docking. Further, we carried out Molecular dynamics simulation analysis to predict the steady binding of top drug-target complexes. The entire MD simulation results analysis was evidence that seven drug-target complexes consistently interacted during the in silico experiment. The top complexes were the target CHLE interacted with 2 PBCs (Pseudojujubogenin and Anahygrine), target VDAC1 interacted with Withanolide R, target THOP1 interacted with Withaolide R, target AOFB interacted with 2 PBCs (Nardostachysin and Viscosalactone B), and target ACHE interacted with the drug (12-Deoxywithastramonolide). These PBCs have stably and flexibly interacted at the protein's active site region. Our results suggest that these PBCs and targets are potential therapeutic candidates for molecular development in AD.

Evaluating anticancer properties of Withaferin A—a potent phytochemical

Withaferin A is a C28 steroidal lactone derived from the plant Withania somnifera, commonly known as Ashwagandha. Withaferin A has received great attention for its anticancer properties noted in cancer cells of various origins. Extracts of Withania somnifera have been used in traditional Ayurvedic and Unani Indian medicine for their various pharmacological benefits. In recent years, Withania somnifera or Ashwagandha extract has become popularized as a health supplement marketed for its stress and anxiety reducing effects. Withaferin A is one of the most studied withanolides extracted from Withania somnifera that has gained great attention for its anticancer, anti-inflammatory, metabolic, and pro-apoptotic effects. Extensive in vivo and in vitro studies have depicted Withaferin A’s interactions with key role players in cancerous activity of the cell to exert its pro-apoptotic effects. Withaferin A interactions with NF-κB, STAT, Hsp90, ER-α, p53, and TGF-β have noted inhibition in cancer cell proliferation and cell cycle arrest in G2/M stage, ultimately leading to apoptosis or cell death. This review highlights pro-apoptotic properties of Withaferin A including generation of reactive oxidative species, Par-4 activation, endoplasmic reticulum stress (ER) induction, and p53 activation. Analysis of Withaferin A’s involvement in various oncogenic pathways leading to malignant neoplasm and its pharmacologic activity in conjunction with various cancer drugs provides promising evidence in therapeutic potential of Withaferin A as a cancer treatment.

Natural withanolides, an update

Covering: March 2010 to December 2020. Previous review: Nat. Prod. Rep., 2011, 28, 705This review summarizes the latest progress and perspectives on the structural classification, biological activities and mechanisms, metabolism and pharmacokinetic investigations, biosynthesis, chemical synthesis and structural modifications, as well as future research directions of the promising natural withanolides. The literature from March 2010 to December 2020 is reviewed, and 287 references are cited.

In Vitro Study of the Bioavailability and Bioaccessibility of the Main Compounds Present in Ayahuasca Beverages

Ayahuasca is a psychoactive beverage that contains the psychoactive compound N,N-dimethyltryptamine and β-carboline alkaloids. This study aims at determining in vitro the bioavailability and bioaccessibility of the main compounds present in decoctions of four individual plants, in a commercial mixture and in four mixtures of two individual plants used in the preparation of Ayahuasca. The samples were subjected to an in vitro digestion process, and the Caco-2 cell line was used as an absorption model. The integrity and permeability of the cell monolayer were evaluated, as well as the cytotoxicity of the extracts. After digestion and cell incubation, the compounds absorbed by the cell monolayer were quantified by high-performance liquid chromatography coupled to a diode array detector. The results showed that compounds such as N,N-dimethyltryptamine, Harmine, Harmaline, Harmol, Harmalol and Tetrahydroharmine were released from the matrix during the in vitro digestion process, becoming bioaccessible. Similarly, some of these compounds, after being incubated with the cell monolayer, were absorbed, becoming bioavailable. The extracts did not show cytotoxicity after cell incubation, and the integrity and permeability of the cell monolayer were not compromised.

Plasma Metabolome Profiling by High-Performance Chemical Isotope-Labelling LC-MS after Acute and Medium-Term Intervention with Golden Berry Fruit (Physalis peruviana L.), Confirming Its Impact on Insulin-Associated Signaling Pathways

Purpose: Golden berry (Physalis peruviana L.) is an exotic fruit exported from Colombia to different countries around the world. A review of the literature tends to demonstrate a hypoglycaemic effect with an improvement in insulin sensitivity after oral ingestion of fruit extracts in animal models. However, little is known about their potential effects in humans, and very little is known about the mechanisms involved. This study aimed at identifying discriminant metabolites after acute and chronic intake of golden berry. Method: An untargeted metabolomics strategy using high-performance chemical isotope-labelling LC-MS was applied. The blood samples of eighteen healthy adults were analysed at baseline, at 6 h after the intake of 250 g of golden berry (acute intervention), and after 19 days of daily consumption of 150 g (medium-term intervention). Results: Forty-nine and 36 discriminant metabolites were identified with high confidence, respectively, after the acute and medium-term interventions. Taking into account up- and downregulated metabolites, three biological networks mainly involving insulin, epidermal growth factor receptor (EGFR), and the phosphatidylinositol 3-kinase pathway (PI3K/Akt/mTOR) were identified. Conclusions: The biological intracellular networks identified are highly interconnected with the insulin signalling pathway, showing that berry intake may be associated with insulin signalling, which could reduce some risk factors related to metabolic syndrome. Primary registry of WHO.

Elucidation of plasma protein binding, blood partitioning, permeability, CYP phenotyping and CYP inhibition studies of Withanone using validated UPLC method: An active constituent of neuroprotective herb Ashwagandha

ETHNOPHARMACOLOGICAL RELEVANCE

Withanone (WN), an active constituent of Withania somnifera commonly called Ashwagandha has remarkable pharmacological responses along with neurological activities. However, for a better understanding of the pharmacokinetic and pharmacodynamic behavior of WN, a comprehensive in-vitro ADME (absorption, distribution, metabolism, and excretion) studies are necessary.

AIM OF THE STUDY

A precise, accurate, and sensitive reverse-phase ultra-performance liquid chromatographic method of WN was developed and validated in rat plasma for the first time. The developed method was successfully applied to the in-vitro ADME investigation of WN.

MATERIAL AND METHODS

The passive permeability of WN was assayed using PAMPA plates and the plasma protein binding (PPB) was performed using the equilibrium dialysis method. Pooled liver microsomes of rat (RLM) and human (HLM) were used for the microsomal stability, CYP phenotyping, and inhibition studies. CYP phenotyping was evaluated using the specific inhibitors. CYP inhibition study was performed using specific probe substrates along with WN or specific inhibitors.

RESULTS

WN was found to be stable in the simulated gastric and intestinal environment and has a high passive permeability at pH 4.0 and 7.0 in PAMPA assay. The PPB of WN at 5 and 20 μg/mL concentrations were found to be high i.e. 82.01 ± 1.44 and 88.02 ± 1.15%, respectively. The in vitro half-life of WN in RLM and HLM was found to be 59.63 ± 2.50 and 68.42 ± 2.19 min, respectively. CYP phenotyping results showed that WN was extensively metabolized by CYP 3A4 and1A2 enzymes in RLM and HLM. However, the results of CYP Inhibition studies showed that none of the CYP isoenzymes were potentially inhibited by WN in RLM and HLM.

CONCLUSION

The in vitro results of pH-dependent stability, plasma stability, permeability, PPB, blood partitioning, microsomal stability, CYP phenotyping, and CYP inhibition studies demonstrated that WN could be a better phytochemical for neurological disorders.

Red laser-mediated alterations in seed germination, growth, pigments and withanolide content of Ashwagandha [Withania somnifera (L.) Dunal]

Withania somnifera (L.) Dunal, generally well-known as Ashwagandha, is part of Indian traditional medicinal systems like Ayurveda, Siddha, and Unani for over 3000 years for treating an array of disorders. The chief bioactive component of this plant is the withanolides, a group of C₂₈-steroidal lactone triterpenoids. These compounds are present in very low concentrations and hence cell culture methods have been used to enhance their production. Low-level laser irradiation has been reported to have elicited the seed germination, agronomical characters, biosynthesis of bioactive compounds in some plants. Therefore, the objective of the study was to investigate the effect of red (He-Ne) laser irradiation on seed germination, growth characters, pigment contents and withanolide content in W. somnifera. The seeds were inoculated onto two different combinations of Murashige and Skoog (MS) media and incubated for germination. The highest germination percentage was observed in ½ MS with pH 6.5 and GA₃ presoaking followed by ½ MS with different pH. Four different doses of Helium-Neon (He-Ne) laser (10, 15, 20 and 25 J/cm²) were used to irradiate the seeds at 632.8 nm and germinated in vitro on ½ MS with pH 6.5. The maximum germination percentage, 63.88% was noted from seeds irradiated with 25 J/cm² (P = 0.04). The highest total length of 13.33 cm was observed in the seedlings irradiated with 25 J/cm² groups (P = 0.008). The highest total chlorophyll content of 329.5 μg/g fresh weight (FW) was observed for seedlings irradiated with 15 J/cm² (P = 0.02) and the highest carotenoid content of 49.6 μg/g FW was observed for 25 J/cm² treated seedlings. Further, primary root length was measured and found to be highest (11.14 cm) in seedlings irradiated with 10 J/cm² and the highest number of lateral roots were observed for 15 and 25 J/cm² groups. The significant amount of Withanolide A (WA) 0.52 μg/g dry weight (DW) and 0.60 μg/g DW was noted in 15 (P = 0.01) and 20 J/cm² (P = 0.002) groups, respectively than control. The present investigation thus reveals the positive impact of red laser on the germination of seeds, growth characters and withanolide contents under in vitro environment.

Exploring the Multifaceted Therapeutic Potential of Withaferin A and Its Derivatives

Withaferin A (WA), a manifold studied, C28-steroidal lactone withanolide found in Withania somnifera. Given its unique beneficial effects, it has gathered attention in the era of modern science. Cancer, being considered a "hopeless case and the leading cause of death worldwide, and the available conventional therapies have many lacunae in the form of side effects. The poly pharmaceutical natural compound, WA treatment, displayed attenuation of various cancer hallmarks by altering oxidative stress, promoting apoptosis, and autophagy, inhibiting cell proliferation, reducing angiogenesis, and metastasis progression. The cellular proteins associated with antitumor pathways were also discussed. WA structural modifications attack multiple signal transduction pathways and enhance the therapeutic outcomes in various diseases. Moreover, it has shown validated pharmacological effects against multiple neurodegenerative diseases by inhibiting acetylcholesterinases and butyrylcholinesterases enzyme activity, antidiabetic activity by upregulating adiponectin and preventing the phosphorylation of peroxisome proliferator-activated receptors (PPARγ), cardioprotective activity by AMP-activated protein kinase (AMPK) activation and suppressing mitochondrial apoptosis. The current review is an extensive survey of various WA associated disease targets, its pharmacokinetics, synergistic combination, modifications, and biological activities.

Withanolides from the genus Physalis: a review on their phytochemical and pharmacological aspects

Objectives

Withanolides are a group of modified C28 ergostane-type steroids with a C-22, C-26 δ-lactone side chain or a C-23, C-26 γ-lactone side chain. They enjoy a limited distribution in the plant kingdom and predominantly occur in several genera of Solanaceae. Of which, the genus Physalis is an important resource for this type of natural molecules. The present review aims to comprehensively illustrate the structural characteristics and classification of withanolides, and particularly focus on the progression on phytochemical and pharmacological aspects of withanolides from Physalis ranging from January 2015 to June 2019.

Key findings

Approximately 351 natural withanolides with novel and unique structures have so far been identified from genus Physalis, mainly isolated from the species of P. angulata and P. peruviana. Withanolides demonstrated diverse biological activity, such as anticancer, anti-inflammatory, antimicrobial, immunoregulatory, trypanocidal and leishmanicidal activity. Their observed pharmacological functions supported the uses of Physalis species in traditional or folk medicines.

Summary

Due to their unique structure skeleton and potent bioactivities, withanolides are regarded to be promising drug candidates, particularly for developing anticancer and anti-inflammatory agents. Further investigations for discovering novel withanolides of genus Physalis, exploiting their pharmacological values and evaluating their potency as therapeutic agents are significant work.

Safety and pharmacokinetics of Withaferin-A in advanced stage high grade osteosarcoma: A phase I trial

Background

Withaferin-A (WA), an active principle obtained from a traditional Indian herb known as Ashwagandha or the Indian ginseng, has been shown to prevent and cure urethane-induced lung tumors in mice, and also inhibit the growth of transplanted sarcoma in mice.

Objectives

In this study, we evaluated the safety and pharmacokinetics of WA in patients with advanced stage high-grade osteosarcoma.

Methods

A phase I dose escalation study was planned using the classical 3 + 3 design (C33D). Dose escalation cohorts comprised of 72, 108, 144 and 216 mg of WA administered in two to four divided doses per day. Three patients were enrolled in each cohort and the last patient was observed for at least 30 days for any dose-limiting toxicity before progressing to a higher cohort. Pharmacokinetic studies were performed using high performance liquid chromatography (HPLC) technique with sensitivity up to 50 ng/ml. Safety evaluation including clinical examination, detailed history of adverse events, Liver Function Tests , Renal Function Tests and complete blood counts were performed at each visit. WA was administered daily till progression. Common Terminology Criteria for Adverse Events (CTCAE) version 3.0 was used for grading adverse events.

Results

The formulation used was generally well tolerated. Eleven adverse events of grade 1 or grade 2 severity were observed. No grade 3 or grade 4 adverse events were observed. Elevation of liver enzymes (5/11) and skin rash (2/11) was the most common adverse events. Other adverse effects include fatigue, fever, edema, and diarrhea (one each). None of the patients had detectable levels of WA in circulation.

Conclusion

The formulation was well tolerated. However, WA appears to have low oral bioavailability. Further studies with improved formulations are warranted.

Hepatoprotective effect of withanolide-rich fraction in acetaminophen-intoxicated rat: decisive role of TNF-α, IL-1β, COX-II and iNOS

CONTEXT

Overdose of acetaminophen (APAP) is common in humans and is often associated with hepatic damage. Withania somnifera (L.) Dunal (Solanaceae) shows multiple pharmacological activities including antioxidant and anti-inflammatory potential.

OBJECTIVE

To evaluate the possible mechanism of hepatoprotective activity of withanolide-rich fraction (WRF) isolated from a methanolic extract of Withania somnifera roots.

MATERIALS AND METHODS

Hepatotoxicity was induced by oral administration of APAP (750 mg/kg, p.o.) for 14 d. The control group received the vehicle. APAP-treated animals were given either silymarin (25 mg/kg) or graded doses of WRF (50, 100 and 200mg/kg) 2 h prior to APAP administration. Animals were killed on 15th day and blood and liver tissue samples were collected for the further analysis.

RESULTS

In WRF-treated group, there was significant and dose-dependent (p < 0.01 and p < 0.001) decrease in serum bilirubin, ALP, AST and ALT levels with significant and dose-dependent (p < 0.01 and p < 0.001) increase in hepatic SOD, GSH and total antioxidant capacity. The level of MDA and NO decreased significantly (p < 0.01) by WRF treatment. Up-regulated mRNA expression of TNF-α, IL-1β, COX-II and iNOS was significantly down-regulated (p < 0.001) by WRF. Histological alternations induced by APAP in liver were restored to near normality by WRF pretreatment.

CONCLUSION

WRF may exert its hepatoprotective action by alleviating inflammatory and oxido-nitrosative stress via inhibition of TNF-α, IL-1β, COX-II and iNOS.

Withania somnifera: From prevention to treatment of cancer

The identification of bioactive molecules that have potential to interrupt carcinogenesis continues to garner research interest. In particular, molecules that have dietary origin are most attractive because of their safety, cost-effectiveness and feasibility of oral administration. Nutraceuticals have played an important role in the overall well-being of humans for many years, with or without rigorous evidence backing their health claims. Traditional medicine systems around the world have utilized plants that have medicinal properties for millennia, providing an opportunity for modern day researchers to assess their efficacies against ailments such as cancer. Withania somnifera (WS) is a plant that has been used in Ayurveda (an ancient form of medicine in Asia) and in the recent past, has been demonstrated to have anti-tumorigenic properties in experimental models. While scientific research performed on WS has exploded in the past decade, much regarding the mode of action and molecular targets involved remains unknown. In this review, we discuss the traditional uses of the plant, the experimental evidence supporting its chemopreventive potential as well as roadblocks that need to be overcome in order for WS to be evaluated as a chemopreventive agent in humans.