Withania somnifera root extract in the regulation of lead-induced oxidative damage in male mouse

Impact of plant extracts on hepatic redox metabolism upon lead exposure: a systematic review of preclinical in vivo evidence

The liver is a central target organ of heavy metals toxicity, and secondary metabolites of several plant species are suggested to attenuate lead (Pb)-induced hepatotoxicity through antioxidant and anti-inflammatory mechanisms. We used a systematic review framework to map the impact of plant extracts and bioactive secondary metabolites on immunological markers and liver redox metabolism in preclinical models of Pb exposure. This is a systematic review performed according to PRISMA guidelines. The structured research of publications was done through PubMed, Scopus, Web of Science, and Embase databases, selecting and analyzing 41 original studies included via the eligibility criteria. Evidence indicates that Pb-exposure increases reactive oxygen/nitrogen species (ROS/RNS) production by δ-aminolevulinic acid auto-oxidation, xanthine dehydrogenase, and xanthine oxidase upregulation. Pb exposure also inhibits antioxidant enzymes, potentiating ROS/NOS levels and reactive cell damage. Plant extracts rich in flavonoids, tannins, alkaloids, anthocyanins, and vitamins exerted hepatoprotective effects by chelating and decreasing Pb bioaccumulation. In addition, plant extracts reinforce exogenous and endogenous antioxidant defenses, attenuating liver oxidative stress and cell death. The lack of blinded evaluators and randomized experimental groups were the main sources of bias identified, which need to be controlled in toxicological studies aimed at identifying natural products applied to the prevention or treatment of Pb poisoning.

Biodiversity, Biochemical Profiling, and Pharmaco-Commercial Applications of Withania somnifera: A Review

Withania somnifera L. Dunal (Ashwagandha), a key medicinal plant native to India, is used globally to manage various ailments. This review focuses on the traditional uses, botany, phytochemistry, and pharmacological advances of its plant-derived constituents. It has been reported that at least 62 crucial and 48 inferior primary and secondary metabolites are present in the W. somnifera leaves, and 29 among these found in its roots and leaves are chiefly steroidal compounds, steroidal lactones, alkaloids, amino acids, etc. In addition, the whole shrub parts possess various medicinal activities such as anti-leukotriene, antineoplastic, analgesic, anti-oxidant, immunostimulatory, and rejuvenating properties, mainly observed by in vitro demonstration. However, the course of its medical use remains unknown. This review provides a comprehensive understanding of W. somnifera, which will be useful for mechanism studies and potential medical applications of W. somnifera, as well as for the development of a rational quality control system for W. somnifera as a therapeutic material in the future.

Chemical Composition, Biological Activity, and Health-Promoting Effects of Withania somnifera for Pharma-Food Industry Applications

The Withania genus comes from the Solanaceae family and includes around 23 species, spread over some areas of the Mediterranean, Asia, and East Africa. Widely used in traditional medicine for thousands of years, these plants are rich in secondary metabolites, with special emphasis on steroidal lactones, named withanolides which are used as ingredients in numerous formulations for a plethora of diseases, such as asthma, diabetes, arthritis, impotence, amnesia, hypertension, anxiety, stress, cancer, neurodegenerative, and cardiovascular diseases, and many others. Among them, Withania somnifera (L.) Dunal is the most widely addressed species from a pharmacological and agroindustrial point of view. In this sense, this review provides an overview of the folk uses, phytochemical composition, and biological activity, such as antioxidant, antimicrobial, anti-inflammatory, and cytotoxic activity of W. somnifera, although more recently other species have also been increasingly investigated. In addition, their health-promoting effects, i.e., antistress, anxiolytic, adaptogenic, antirheumatoid arthritis, chemoprotective, and cardiorespiratory-enhancing abilities, along with safety and adverse effects are also discussed.

The Positive Role and Mechanism of Herbal Medicine in Parkinson's Disease

Parkinson's disease (PD) is a complex neurodegenerative disease, manifested by the progressive functional impairment of the midbrain nigral dopaminergic neurons. Due to the unclear underlying pathogenesis, disease-modifying drugs for PD remain elusive. In Asia, such as in China and India, herbal medicines have been used in the treatment of neurodegenerative disease for thousands of years, which recently attracted considerable attention because of the development of curative drugs for PD. In this review, we first summarized the pathogenic factors of PD including protein aggregation, mitochondrial dysfunction, ion accumulation, neuroinflammation, and oxidative stress, and the related recent advances. Secondly, we summarized 32 Chinese herbal medicines (belonging to 24 genera, such as Acanthopanax, Alpinia, and Astragalus), 22 Chinese traditional herbal formulations, and 3 Indian herbal medicines, of which the ethanol/water extraction or main bioactive compounds have been extensively investigated on PD models both in vitro and in vivo. We elaborately provided pictures of the representative herbs and the structural formula of the bioactive components (such as leutheroside B and astragaloside IV) of the herbal medicines. Also, we specified the potential targets of the bioactive compounds or extractions of herbs in view of the signaling pathways such as PI3K, NF-κB, and AMPK which are implicated in oxidative and inflammatory stress in neurons. We consider that this knowledge of herbal medicines or their bioactive components can be favorable for the development of disease-modifying drugs for PD.

Role of medicinal plants against neurodegenerative diseases

Diseases with a significant loss of neurons, structurally and functionally are termed as neurodegenerative diseases. Due to the present therapeutic interventions and progressive nature of diseases, a variety of side effects have risen up, thus leading the patients to go for an alternative medication. The role of medicinal plants in such cases has been beneficial because of their exhibition via different cellular and molecular mechanisms. Alleviation in inflammatory responses, suppression of the functionary aspect of pro-inflammatory cytokines like a tumor, improvement in antioxidative properties is among few neuroprotective mechanisms of traditional plants. Variation in transcription and transduction pathways play a vital role in the preventive measures of plants in such diseases. Neurodegenerative diseases are generally caused by depletion of proteins, oxidative and inflammatory stress, environmental changes and so on, with aging being the most important cause. Natural compounds can be used in order to treat neurodegenerative diseases Medicinal plants such as Ginseng, Withania somnifera, Bacopa monnieri, Ginkgo biloba, etc. are some of the medicinal plants for prevention of neurological symptoms. This review deals with the use of different medicinal plants for the prevention of neurodegenerative diseases.

Withania somnifera (L.) Dunal - Modern perspectives of an ancient Rasayana from Ayurveda

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera (L.) Dunal, commonly known as Ashwagandha, is an important medicinal plant that has been used in Ayurvedic and indigenous medicine for more than 3000 years. According to Charaka Samhita, Susruta Samhita and other ancient texts, Ashwagandha is known as Balya (increases strength), Brusya (sexual performance enhancer), vajikari (spermatogenic), Kamarupini (libido-enhancing), Pustida (nourishing).

AIM OF THE REVIEW

This review article documented and critically assessed W. somnifera regarding its ethnopharmacology, traditional use, botanical description, phytochemicals present, pharmacological activities, clinical trials, and marketed formulations.

MATERIALS AND METHODS

The sources of information used in the study are traditional Ayurvedic books like Charaka Samhita, Susruta Samhita, Astanga Hridaya etc, government reports, dissertations, books, research articles and databases like Science-Direct, SciFinder, Web of Science, PubMed, Wiley Online Library, and ACS Publications on Ashwagandha and Withania somnifera (L.) Dunal.

RESULTS

Traditional uses of Ashwagandha in Ayurveda are very prominent in several texts where formulations with various dosage forms have been mentioned in Charaka Samhita, Susruta Samhita, Astanga Hridaya, different nighantus etc. The drugs were identified based on their composition containing Ashwagandha as one of the major ingredients and their medicinal uses. Phytochemical studies on W. somnifera revealed the presence of important chemical constituents such as flavonoids, phenolic acids, alkaloids, saponins, tannins, and withanolides. The phytochemicals showed various pharmacological activities like anti-cancer, immunomodulatory, cardioprotective, neuroprotective, anti-aging, anti-stress/adaptogenic and anti-diabetic. Various clinical trials show that the plant extract and its bioactive compounds are used in the prevention and treatment of many diseases, such as arthritis, impotence, amnesia, anxiety, cancer, neurodegenerative and cardiovascular diseases, and others.

CONCLUSIONS

Pharmacological data reviewed here revealed that W. somnifera is a potential source for the treatment of a wide range of diseases especially anxiety and other CNS disorders. From its ancient use to its modern application it has been proven to be non-toxic and effective clinically for human health and wellness. W. somnifera based herbal formulation has been marketed in the form of supplement, extract, capsule, powder etc. This review will be helpful to correlate the mechanism of action with the phytochemical profile of this well-known plant from Ayurveda.

Withania somnifera alleviates parkinsonian phenotypes by inhibiting apoptotic pathways in dopaminergic neurons

Maneb (MB) and paraquat (PQ) are environmental toxins that have been experimentally used to induce selective damage of dopaminergic neurons leading to the development of Parkinson's disease (PD). Although the mechanism of this selective neuronal toxicity in not fully understood, oxidative stress has been linked to the pathogenesis of PD. The present study investigates the mechanisms of neuroprotection elicited by Withania somnifera (Ws), a herb traditionally recognized by the Indian system of medicine, Ayurveda. An ethanolic root extract of Ws was co-treated with the MB-PQ induced mouse model of PD and was shown to significantly rescue canonical indicators of PD including compromised locomotor activity, reduced dopamine in the substantia nigra and various aspects of oxidative damage. In particular, Ws reduced the expression of iNOS, a measure of oxidative stress. Ws also significantly improved the MB + PQ mediated induction of a pro-apoptotic state by reducing Bax and inducing Bcl-2 protein expression, respectively. Finally, Ws reduced expression of the pro-inflammatory marker of astrocyte activation, GFAP. Altogether, the present study suggests that Ws treatment provides nigrostriatal dopaminergic neuroprotection against MB-PQ induced Parkinsonism by the modulation of oxidative stress and apoptotic machinery possibly accounting for the behavioural effects.

Withania somnifera ameliorates lead-induced augmentation of adrenergic response in rat portal vein

OBJECTIVES

Present study was undertaken to elucidate the ameliorating potential of Withania somnifera root extract (WRE) against lead-induced augmentation of adrenergic response in rat portal vein.

MATERIALS AND METHODS

In-vitro studies were conducted on effect of lead alone and lead+WRE on rat-isolated portal vein while in-vivo studies were done in three groups of 12 rats each; Group-II and III received 0.5% lead acetate and 1.0% WRE + 0.5% lead acetate, respectively, in drinking water for 12 weeks whereas group-I served as control. Adrenaline and noradrenaline levels in brain and blood were determined by HPLC assay while vascular reactivity of portal vein to lead and WRE was determined by measuring the isometric tension.

RESULTS

Following in-vitro exposure, lead did not alter the contractile effect of phenylephrine. In-vivo studies revealed that contractile effect of lead on portal vein was significantly potentiated and it was antagonized by prazosin (10(-7) M) and WRE (1%). WRE treatment significantly reduced elevated blood noradrenaline (37.80%) and restored noradrenaline level in brain (39.39%) in lead-exposed animals. These values were almost comparable to the control group. But it failed to significantly affect the blood and brain adrenaline levels.

CONCLUSIONS

Results suggest that following pre-exposure of rats to WRE, lead-induced augmentation of alpha 1-adrenoceptors mediated response was reversed possibly by regulating catecholamine release from nerve endings. Thus, WRE may be useful in therapeutic management of lead-induced hypertension.

Habb-e-Asgand, polyherbal Unani formulation, protects liver and antioxidative enzymes against paracetamol induced hepatotoxicity

Abstract Context: Habb-e-Asgand, a polyherbal Homeopathy/Unani drug from Hamdard Wakf Laboratory, India, used in arthritis, gout and joint pain, is a mixture of many herbal medicinal plants. Scientific attempts to test and validate its efficacy are meager. Objective: To evaluate the hepatoprotective and antioxidative potential of Habb-e-Asgand against paracetamol toxicity. Materials and methods: Swiss albino male mice (n = 5/group) were treated with Habb-e-Asgand (250 mg/kg, body weight (b.w.) in normal saline orally for 14 days followed by a single dose of paracetamol (400 mg/kg b.w./normal saline) intraperitoneally 24 h before euthanization. We estimated liver function (LFTs) using diagnostic kits, while antioxidant enzymes, cytochrome P450 (CYP) and lipid peroxidation (LPO) were measured using spectrophotometric methods. Results: Paracetamol alone induced LFTs enzymes significantly (p < 0.05 and p < 0.01, 0.001), serum glutamate pyruvate transaminase (SGPT, ∼70%), serum glutamate oxaloacetate transaminase (SGOT, ∼20%), alkaline phosphatase (ALP, ∼20%), total bilirubin (∼30%), CYP activity (∼50%) and LPO (∼45%), while it significantly inhibited the activity of antioxidant enzymes glutathione reductase (GR, ∼35%), glutathione peroxidase (GPx, ∼40%), glutathione S-tranferase (GST, ∼16%), catalase (CAT, ∼84%) and glutathione (GSH, ∼30%) contents. Habb-e-Asgand alone and in combination of paracetamol significantly (p < 0.05, 0.01, 0.001) decreased LFT levels (20-25%), CYP activity (∼45%) and LPO level (∼25%), while it induced antioxidant enzyme activity (GR, ∼15%; GPx, ∼17%; GST, ∼20% and CAT, ∼60%). Discussion: Paracetamol metabolites may be mediating production of reactive oxidant species (ROS) and liver injury, which are attenuated by Habb-e-Asgand antioxidant constituents. Conclusion: Habb-e-Asgand may be used as a prophylaxis for ROS related liver injury.

Withania somnifera root extract ameliorates hypobaric hypoxia induced memory impairment in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera (WS) root extract has been used traditionally in ayurvedic system of medicine as a memory enhancer and anti-stress agent.

AIM OF THE STUDY

To evaluate the neuroprotective and prophylactic potential of WS root extract in ameliorating hypobaric hypoxia (HH) induced memory impairment and to explore the underlying molecular mechanism.

MATERIALS AND METHODS

WS root extract was administered to male Sprague Dawley rats during a period of 21 days pre-exposure and 07 days exposure to a simulated altitude of 25,000 ft. Spatial memory was assessed by Morris Water Maze. Neurodegeneration, corticosterone, acetylcholine (Ach) levels, acetylcholine esterase (AchE) activity, oxidative stress markers and nitric oxide (NO) concentration were assessed in the hippocampus. Synaptic and apoptotic markers were also investigated by immunoblotting. To study the role of NO in regulating corticosterone mediated signaling, the neuronal nitric oxide synthase (n-NOS) inhibitor, L-Nitro-arginine methyl ester (L-Name) and NO agonist sodium nitroprusside (SNP) were administered from 3rd to 7th day of hypoxic exposure.

RESULTS

Administration of WS root extract prevented HH induced memory impairment and neurodegeneration along with decreased NO, corticosterone, oxidative stress and AchE activity in hippocampal region. Inhibition of NO synthesis by administration of L-Name reduced corticosterone levels in hippocampus during hypoxic exposure while co-administration of corticosterone increased neurodegeneration. Administration of sodium nitroprusside (SNP) along with WS root extract supplementation during hypoxic exposure increased corticosterone levels and increased the number of pyknotic cells.

CONCLUSION

WS root extract ameliorated HH induced memory impairment and neurodegeneration in hippocampus through NO mediated modulation of corticosterone levels.

In vitro protective effects of Withania somnifera (L.) dunal root extract against hydrogen peroxide and β-amyloid(1-42)-induced cytotoxicity in differentiated PC12 cells

Withania somnifera L. Dunal (Solanaceae), also known as 'ashwagandha' in Sanskrit and as 'Indian ginseng', is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as traditionally used, against H(2)O(2)- and Aβ((1-42))-induced cytotoxicity which are current targets for novel approaches to treat dementia, especially dementia of the Alzheimer's type (AD). In this study, an aqueous extract prepared from the dried roots of W. somnifera was assessed for potential protective effects against H(2)O(2)- and Aβ((1-42))-aggregated fibril cytotoxicity by an MTT assay using a differentiated rat pheochromocytoma PC12 cell line. The results suggest that pretreatments of differentiated PC12 cells with aqueous extracts of W. somnifera root significantly protect differentiated PC12 cells against both H(2)O(2)- and Aβ((1-42))-induced cytotoxicity, in a concentration dependent manner. To investigate the compounds that could explain the observed effects, the W. somnifera extract was analysed by liquid chromatography-serial mass spectrometry and numerous withanolide derivatives, including withaferin A, were detected. These results demonstrate the neuroprotective properties of an aqueous extract of W. somnifera root and may provide some explanation for the putative ethnopharmacological uses of W. somnifera for cognitive and other neurodegenerative disorders that are associated with oxidative stress.

The chemopreventive effects of Protandim: modulation of p53 mitochondrial translocation and apoptosis during skin carcinogenesis

Protandim, a well defined dietary combination of 5 well-established medicinal plants, is known to induce endogenous antioxidant enzymes, such as manganese superoxide dismutase (MnSOD). Our previous studies have shown through the induction of various antioxidant enzymes, products of oxidative damage can be decreased. In addition, we have shown that tumor multiplicity and incidence can be decreased through the dietary administration of Protandim in the two-stage skin carcinogenesis mouse model. It has been demonstrated that cell proliferation is accommodated by cell death during DMBA/TPA treatment in the two-stage skin carcinogenesis model. Therefore, we investigated the effects of the Protandim diet on apoptosis; and proposed a novel mechanism of chemoprevention utilized by the Protandim dietary combination. Interestingly, Protandim suppressed DMBA/TPA induced cutaneous apoptosis. Recently, more attention has been focused on transcription-independent mechanisms of the tumor suppressor, p53, that mediate apoptosis. It is known that cytoplasmic p53 rapidly translocates to the mitochondria in response to pro-apoptotic stress. Our results showed that Protandim suppressed the mitochondrial translocation of p53 and mitochondrial outer membrane proteins such as Bax. We examined the levels of p53 and MnSOD expression/activity in murine skin JB6 promotion sensitive (P+) and promotion-resistant (P-) epidermal cells. Interestingly, p53 was induced only in P+ cells, not P- cells; whereas MnSOD is highly expressed in P- cells when compared to P+ cells. In addition, wild-type p53 was transfected into JB6 P- cells. We found that the introduction of wild-type p53 promoted transformation in JB6 P- cells. Our results suggest that suppression of p53 and induction of MnSOD may play an important role in the tumor suppressive activity of Protandim.

Protective effect of Withania somnifera root powder on lipid peroxidation and antioxidant status in gentamicin-induced nephrotoxic rats

We investigated the protective effect of Withania somnifera root powder (used in ayurvedic medicine in India) on gentamicin (GEN) induced nephrotoxicity in male Wistar rats. The root powder was administered orally to rats for 14 days before GEN treatment and thereafter with GEN for 8 days. Nephrotoxicity was manifested in GEN-treated rats as significant increases in urea, creatinine, uric acid, non protein nitrogen, urinary protein, N-acetyl-beta-D-glucosaminidase, thiobarbituric acid reactive substances, hydroperoxides, followed by a significant reduction in glutathione peroxidase, superoxide dismutase, catalase, and reduced glutathione in liver and kidney tissues, histopathologically confirmed by tubular necrosis. W. somnifera treatment altered the antioxidant status and significantly reversed the levels as seen microscopically. The results show that the root powder of W. somnifera with the presence of natural antioxidants, bioflavanoids, and other bioactive compounds scavenged the free radicals generated by GEN and ameliorated the severity of GEN-induced nephrotoxicity by enhancing the antioxidant system and protecting the cellular integrity of kidney and liver tissues.

Protective Role of Tinospora cordifolia against Lead-induced Hepatotoxicity

The importance of Tinospora cordifolia stem and leaves extract was investigated for its possible hepatoprotective effect in Swiss albino male mice against lead nitrate induced toxicity. Oral administration of plant extracts prevented the occurrence of lead nitrate induced liver damage. The decreased level of tissue enzymes, i.e., superoxide dismutase (SOD), catalase (CAT) and increased level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and acid phosphatase (ACP) were observed in mice treated with lead. Administration of aqueous stem extract (400 mg/kg body weight, orally) and aqueous leaves extract (400 mg/kg body weight, orally) along with the lead nitrate (5 mg/kg body weight, i.p. for 30 days) increased the activities of SOD and CAT and decreased the levels of AST, ALT, ALP, and ACP enzymes in mice. These biochemical observations were supplemented by histopathology/histological examinations of liver section. Results of this study revealed that plant extract could afford protection against lead-induced hepatic damage.

Neuroprotective effects of Withania somnifera dunal.: A possible mechanism

Present study was carried out to understand the possible mechanism of neuroprotective action of the root extract of Withania somnifera Dunal (WS). The study is focused on WS mediated inhibition of nitric oxide production, which is known to mediate neurodegeneration during stress. Adult mice (28 +/- 5 g) were exposed to restraint stress for 30 days. Activity of NADPH diaphorase (NADPH-d) and factors (Acetylcholine, serotonin and corticosterone), which regulates NADPH-d activity were studied. Treatment with WS extract for 30 days during stress, significantly reversed the stress induced NADPH-d activation. Observations suggest that inhibition of NADPH-d by WS is not a direct effect of extract on NADPH-d, instead it inhibits via suppressing corticosterone release and activating cholineacetyltransferase, which in turn increase serotonin level in hippocampus to inhibit NADPH-d. Together, the main mechanism underlying the neuroprotective effects of WS can be attributed to its role in the down regulation of nNOS and neurochemical alterations of specific neurotransmitter systems. These observations thus suggest that WS root extract could be developed as a potential preventive or therapeutic drug for stress induced neurological disorders.

Protandim, a fundamentally new antioxidant approach in chemoprevention using mouse two-stage skin carcinogenesis as a model

Oxidative stress is an important contributor to cancer development. Consistent with that, antioxidant enzymes have been demonstrated to suppress tumorigenesis when being elevated both in vitro and in vivo, making induction of these enzymes a more potent approach for cancer prevention. Protandim, a well-defined combination of widely studied medicinal plants, has been shown to induce superoxide dismutase (SOD) and catalase activities and reduce superoxide generation and lipid peroxidation in healthy human subjects. To investigate whether Protandim can suppress tumor formation by a dietary approach, a two-stage mouse skin carcinogenesis study was performed. At the end of the study, the mice on a Protandim-containing basal diet had similar body weight compared with those on the basal diet, which indicated no overt toxicity by Protandim. After three weeks on the diets, there was a significant increase in the expression levels of SOD and catalase, in addition to the increases in SOD activities. Importantly, at the end of the carcinogenesis study, both skin tumor incidence and multiplicity were reduced in the mice on the Protandim diet by 33% and 57% respectively, compared with those on basal diet. Biochemical and histological studies revealed that the Protandim diet suppressed tumor promoter-induced oxidative stress (evidenced by reduction of protein carbonyl levels), cell proliferation (evidenced by reduction of skin hyperplasia and suppression of PKC/JNK/Jun pathway), and inflammation (evidenced by reduction of ICAM-1/VCAM-1 expression, NF-κB binding activity, and nuclear p65/p50 levels). Overall, induction of antioxidant enzymes by Protandim may serve as a practical and potent approach for cancer prevention.

Protective effect of Withania somnifera root powder in relation to lipid peroxidation, antioxidant status, glycoproteins and bone collagen on adjuvant-induced arthritis in rats

The present investigation was carried out to evaluate the protective effect of Withania somnifera Linn. Dunal (family-Solanaceae), commonly known as Ashwagandha, on adjuvant-induced arthritic rats. Results were compared with those for Indomethacin, a nonsteroidal anti-inflammatory drug. Arthritis was induced by intradermal injection of complete Freund's adjuvant (0.1 mL) into the right hind paw of Wistar albino rats. Withania somnifera root powder (1000 mg/kg/day) and Indomethacin (3 mg/kg/day) were orally administered for 8 days (from 11th to 18th day) after adjuvant injection. The anti-arthritic effect of W. somnifera root powder was assessed by measuring changes in lipid peroxidation, antioxidant status, and glycoprotein levels in plasma and spleen of arthritic animals. In addition, cartilage degradation was also assessed by estimating bone collagen, and urinary constituents in arthritic animals. Results of the present investigation showed significant increase in the level of lipid peroxides, glycoproteins, and urinary constituents with the depletion of antioxidant status and bone collagen in arthritic animals. These biochemical alterations observed were ameliorated significantly by oral administration of W. somnifera root powder (1000 mg/kg body weight) in arthritic animals. The results of this study clearly indicate that W. somnifera root powder is capable of rectifying the above biochemical changes in adjuvant arthritis.

Protective effect of Withania somnifera (Solanaceae) on collagen glycation and cross-linking

Modification of collagen such as non-enzymatic glycation and cross-linking plays an important role in diabetic complications and age-related diseases. We evaluate the effect of Withania somnifera on glucose-mediated collagen glycation and cross-linking in vitro. Extent of glycation, viscosity, collagen-linked fluorescence and pepsin solubility were assessed in different experimental procedures to investigate the effect of W. somnifera. Tail tendons obtained from rats (Rattus norvegicus) weighing 250-275 g were incubated with 50 mM glucose and 100 mg of metformin or Withania root powder or ethanolic extract of Withania under physiological conditions of temperature and pH for 30 days. Formation of advanced glycation end products (AGE) was measured by fluorescent method whereas the cross-linking of collagen was assessed by pepsin digestion and viscosity measurements. Tendon collagen incubated with glucose showed an increase in glycation, AGE and cross-linking of collagen. The collagen incubated with W. somnifera and metformin ameliorates these modifications. The ethanolic extract of Withania showed more prominent effect than Withania root powder. The activity of ethanolic extract of Withania is comparable to metformin, a known antiglycating agent. In conclusion, Withania could have therapeutic role in the prevention of glycation induced pathogenesis in diabetes mellitus and aging.

The protective effect of a purified extract of Withania somnifera against doxorubicin-induced cardiac toxicity in rats

The therapeutic value of doxorubicin as an effective antineoplastic agent is limited by its cardiotoxic side-effects. The administration of doxorubicin (10 mg/kg) to male Wistar rats induced necrosis and apoptosis in heart tissues. It also caused oxidative stress damage as evidenced by the elevation of malondialdehyde and protein carbonyl levels and catalase activity, accompanied by the concurrent depletion of total antioxidant capacity and of superoxide dismutase level in cardiac tissues. The doxorubicin-induced cardiotoxicity and oxidative stress damage were also accompanied by increases of myeloperoxidase activity, total calcium content, and the expression of Bcl-2 protein in heart tissues. Most of these doxorubicin-induced biochemical and histological alterations were effectively attenuated by prior administration of purified standardized extract (1.5% withanolides; manufactured by Idea Sphere Inc., American Fork, UT, USA) of Withania somnifera (300 mg/kg). Thus, Withania may play a role in the protection against cardiotoxicity and thus might be a useful adjuvant therapy where doxorubicin is the cancer-treating drug.

Oxidative damage in liver after perinatal intoxication with lead and/or cadmium

Lead acetate (300 mg Pb/L) and/or cadmium acetate (10mg Cd/L) in blood and liver were administrated as drinking water to pregnant Wistar rats from day 1 of pregnancy to parturition (day 0) or until weaning (day 21), to investigate the toxic effects in blood and in the liver. Both metals produced mycrocitic anaemia in the pups as well as oxidative damage in the liver, as suggested by the significant increase in TBARS production and the high catalase activity. Moreover, intense alkaline and acid phosphatase activity, used as biomarkers of liver adaptation to damaging factors, was observed. In addition, the toxikinetics are different for Pb and Cd: while Cd is a hepatotoxic from day 0, Pb is not until day 21. Finally, simultaneous perinatal administration of both metals seems to protect, at least, in the liver TBARS production against the toxicity produced by Cd or Pb separately.

Neuroprotective effects of Withania somnifera on 6-hydroxydopamine induced Parkinsonism in rats

6-Hydroxydopamine (6-OHDA) is one of the most widely used rat models for Parkinson's disease. There is ample evidence in the literature that 6-OHDA elicits its toxic manifestations through oxidant stress. In the present study, we evaluated the anti-parkinsonian effects of Withania somnifera extract, which has been reported to have potent anti-oxidant, anti-peroxidative and free radical quenching properties in various diseased conditions. Rats were pretreated with 100, 200 and 300 mg/kg b.w. of the W. somnifera extract orally for 3 weeks. On day 21, 2 microL of 6-OHDA (10 microg in 0.1% in ascorbic acid-saline) was infused into the right striatum while sham operated group received 2 microL of the vehicle. Three weeks after 6-OHDA injections, rats were tested for neurobehavioral activity and were killed 5 weeks after lesioning for the estimation of lipidperoxidation, reduced glutathione content, activities of glutathione-S-transferase, glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase, catecholamine content, dopaminergic D2 receptor binding and tyrosine hydroxylase expression. W. somnifera extract was found to reverse all the parameters significantly in a dose-dependent manner. Thus, the study demonstrates that the extract of W. somnifera may be helpful in protecting the neuronal injury in Parkinson's disease.

Antioxidant approach to disease management and the role of 'Rasayana' herbs of Ayurveda

The disease preventive and health promotive approach of 'Ayurveda', which takes into consideration the whole body, mind and spirit while dealing with the maintenance of health, promotion of health and treating ailments is holistic and finds increasing acceptability in many regions of the world. Ancient Ayurvedic physicians had developed certain dietary and therapeutic measures to arrest/delay ageing and rejuvenating whole functional dynamics of the body system. This revitalization and rejuvenation is known as the 'Rasayan chikitsa' (rejuvenation therapy). Traditionally, Rasayana drugs are used against a plethora of seemingly diverse disorders with no pathophysiological connections according to modern medicine. Though, this group of plants generally possesses strong antioxidant activity, only a few have been investigated in detail. Over about 100 disorders like rheumatoid arthritis, hemorrhagic shock, CVS disorders, cystic fibrosis, metabolic disorders, neurodegenerative diseases, gastrointestinal ulcerogenesis and AIDS have been reported as reactive oxygen species mediated. In this review, the role of free radicals in these diseases has been briefly reviewed. 'Rasayana' plants with potent antioxidant activity have been reviewed for their traditional uses, and mechanism of antioxidant action. Fifteen such plants have been dealt with in detail and some more plants with less work have also been reviewed briefly.