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1.
The efficacy of Withania somnifera (Ws) to limit myocardial injury after ischemia and reperfusion was explored and compared to that of Vit E, a reference standard known to reduce mortality and infarct size due to myocardial infarction. Wistar rats (150–200 g) were divided into six groups and received orally saline (sham, control group), Ws-50/kg (Ws control and treated group) and Vit E-100 mg/kg (Vit E control and treated group) respectively for 1 month. On the 31st day, rats of the control, Vit E and Ws treated groups were anesthetized and subjected to 45 min occlusion of the LAD coronary artery followed by 60 min reperfusion. Hemodynamic parameters: systolic, diastolic and mean arterial pressure (SAP, DAP, MAP), heart rate (HR), left ventricular end diastolic pressure (LVEDP), left ventricular peak (+) LVdP/dt and (–) LVdP/dt were monitored. Hearts were removed and processed for histopathological and biochemical studies: Myocardial enzyme viz, creatin phosphokinase (CPK), and antioxidant parameters: malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) were estimated. Postischemic reperfusion produced significant cardiac necrosis, depression of left ventricular functions (MAP, LVEDP, (+) and (–) LVdP/dt) and a significant fall in GSH (p < 0.01), SOD, CAT(p < 0.05), LDH and CPK (p < 0.01) as well as an increase in MDA level (p < 0.05) in the control group rats as compared to sham group. The changes in levels of protein and GPx was however, not significant. Ws and Vit E favorably modulated most of the hemodynamic, biochemical and histopathological parameters though no significant restoration in GSH, MAP (with Vit E) were observed. Ws on chronic administration markedly augmented antioxidants (GSH, GSHPx, SOD, CAT) while Vit E did not stimulate the synthesis of endogenous antioxidants compared to sham. Results indicate that Ws significantly reduced myocardial injury and emphasize the beneficial action of Ws as a cardioprotective agent.  相似文献   

2.
Renal ischemia/reperfusion (I/R) injury resulting in acute renal failure, is a major clinical problem due to its high mortality rate. Renal I/R increases the reactive oxygen species, secretion of inflammatory cytokines, chemokines and other factors. This suggests that initiating the apoptosis process in the presence of oxidative stress may play a role in life-threatening conditions, such as ischemia. Ischemia reperfusion-induced renal damage can result in renal failure and death. Although many treatment procedures have been carried out to reduce or destroy renal I/R damage in experimental models, so far, a routine method of treatment has not yet been found. For this reason, the current study was planned to investigate the possible protective effects of evodiamine on tissue damage caused by ischemia-reperfusion in kidney tissue in rats and an experimental renal I/R model was used for this purpose. Four groups were formed in the study: the control, sham control, ischemia reperfusion (I/R), and evodiamine (10 mg/kg) + I/R groups. The effects of evodiamine against kidney I/R injury were investigated. TAS (total oxidant status), TOS (total oxidant status), interleukin-1β (IL-1β), IL-6, IL-10 and tumor necrosis factor-α levels were determined by enzyme-linked immunosorbent assay. The oxidative stress index was calculated from TAS and TOS levels. In addition, the renal ischemia reperfusion injury was examined histopathologically. The IL-10 and TAS levels in the I/R group decreased when compared with the control and Sham groups, while these levels increased in the evodiamine group. Histopathologic examination revealed that caspase 3 and nuclear factor-κB levels decreased in the evodiamine group compared with the I/R group. The application of evodiamine significantly reduced ischemia reperfusion-induced kidney damage due to its antioxidant, anti-inflammatory and antiapoptotic properties.  相似文献   

3.
Withania somnifera has been an important herb in the Ayurvedic and indigenous medical systems for centuries in India. However, these grow as weeds mostly in the wastelands, which receive contaminated water from municipal and industrial sources. In the present investigation, plants of Withania somnifera were exposed to various concentrations of arsenate (AsV) and arsenite (AsIII) (0, 10, 25, 50, 100 μM) for 10 days and analysed for accumulation of arsenic (As) and physiological and biochemical changes. Plants showed more As accumulation upon exposure to AsIII (320 μg g−1 DW in roots and 161 μg g−1 DW in leaves) than to AsV (173 μg g−1 DW in roots and 100 μg g−1 DW in leaves) after 10 days of treatment. Consequently, AsIII exposure caused more toxicity to plants as compared to that AsV, as evaluated in terms of the level of photosynthetic pigments and oxidative stress parameters (superoxide, hydrogen peroxide and lipid peroxidation), particularly at higher concentrations and on longer durations. Plants could tolerate low concentrations (variable for AsIII and AsV) until longer durations (10 days) and high concentrations for shorter durations (1–5 days) through increase in antioxidant enzymes and by augmented synthesis of thiols. In conclusion, As tolerance potential of Withania plants on one hand advocates its prospective use for remediation under proper supervision and on the other demonstrates possible threat of As entry into humans due to medicinal uses.  相似文献   

4.
Complex signal-transduction cascades are known to be involved in regulating cardiomyocyte function, death and survival during acute cardiac ischemia-reperfusion process, but detailed survival signalling pathways are not clear. This review presents and discusses the recent findings bearing upon the evidence on the cardioprotective effect of sphingosine-1-phosphate (S1P) and bradykinin in acute cardiac ischemia-reperfusion and underlying signalling mechanisms, particularly, through activation of P21 activated kinase.  相似文献   

5.
Medicinal plants are extensively utilized in traditional and herbal medicines, both in India and around the world due to the presence of diverse low molecular weight natural products such as flavonoids, alkaloids, terpenoids and sterols. Flavonoids which have health benefits for humans are the large class of phenylpropanoid-derived secondary metabolites and are mostly glycosylated by UDP-glycosyltransferases (UGTs). Although large numbers of different UGTs are known from higher plants, very few protein structures have been reported till now. In the present study, the three-dimensional model of flavonoid specific glycosyltransferases (WsFGT) from Withania somnifera was constructed based on the crystal structure of plant UGTs. The resulted model was assessed by various tools and the final refined model revealed GT-B type fold. Further, to understand the sugar donors and acceptors interactions with the active site of WsFGT, docking studies were performed. The amino acids from conserved PSPG box were interacted with sugar donor while His18, Asp110, Trp352 and Asn353 were important for catalytic function. This structural and docking information will be useful to understand the glycosylation mechanism of flavonoid glucosides.

Abbreviations

DOPE - Discrete Optimized Potential Energy, PDB - Protein Data Bank, PSPG - Plant Secondary Product Glycosyltransferase, RMSD - Root Mean Squared Deviation, UDP - Uridine diphosphate, UGT - UDP-glycosyltransferases.  相似文献   

6.
Four (1, 8-10) and six known (2-7) withanolides were isolated from the leaves of Withania somnifera. Among the new compounds, 10 possessed the rare 3-O-sulfate group with the saturation in A ring and 9 contained unusual 1,4-dien-3-one group. Compound 8 did not have usual 2,3 unsaturation in A ring while 1 had the rare C-16 double bond. The structures of all the compounds were elucidated by spectroscopic methods and chemical transformation.  相似文献   

7.
Xi JK  Jin YZ  Cui X  Xu Z 《生理学报》2007,59(5):553-561
局部缺血部位快速再灌注虽然保护了心肌,但也引起再灌注损伤。目前还没有减轻再灌注损伤的特效疗法,但近年来研究显示,G蛋白耦联受体(Gprotein-coupledreceptor,GPCR)的激动剂、胰岛素和缺血后处理可以在各种实验条件和各类动物模型中有效抵抗再灌注损伤。这些干预手段启动的心脏保护机制可能包括激活再灌注损伤补救激酶(reperfus ioninjury salvage kinase,RISK)途径、抑制糖原合酶激酶-3β(glycogen synthase kinase3β,GSK-3β)以及抑制线粒体膜通透性转换孔(mitochondrial permeabili tytransition pore,mPTP)开放等。这些研究成果有利于开发治疗急性心肌梗死的有效临床手段。  相似文献   

8.
Shoot multiplication was achieved in vitro from shoot tips of aseptically germinated seedlings of Withania somnifera L. using low concentrations of 6-benzyladenine (BA), viz. 2.2, 4.4 and 8.9 M. Maximum number of shoots were obtained when 2.3 M 2,4-dichlorophenoxyacetic acid (2,4-D) or 2.5 M indolebutyric acid (IBA) was added to medium containing 4.4 M BA during initiation of shoot multiplication, but not when added later. Direct multiple shoot initiation was also obtained from germinating seeds in the presence of BA alone. Rooting was successful in excised shoots grown on growth regulator-free MS medium. Rooted shoots were successfully established in soil in a greenhouse.  相似文献   

9.
目的:研究雷米普利与BQ-123合用对大鼠在体心肌缺血/再灌注损伤的影响。方法:健康雄性Wistar大鼠随机分为5组,制备缺血30min再灌注120min模型,采用雷米普利、BQ-123单用及两药联合应用的方式处理实验动物。观察两药合用对大鼠在体心肌缺血/再灌注损伤的保护作用。观察动物心率、血压、心电图ST-段变化,记录缺血期室性心律失常;检测血浆CK及LDH活力;心肌HE染色和TIC染色,定性和定量检测心肌梗死情况。结果:与I/R组比较,各给药组ST-段均明显降低;缺血期室性心律失常(VA)出现时间明显推迟且持续时间明显缩短,联合给药组作用更为显著;心律失常发生率明显降低;血浆CK及LDH活力显著降低且联合给药组降低更为显著;梗死面积明显缩小,心肌损伤程度明显减轻,其中联合给药组变化更为显著。结论:雷米普利、BQ-123单用及联合应用均对大鼠在体心肌缺血/再灌注损伤有保护作用,且两药合用在推迟缺血期VA的出现时间,缩短其持续时间,减少CK及LDH漏出,缩小心肌梗死面积方面优于两药各自单用。  相似文献   

10.
A phospholipase inhibitor (WSG) has been purified from Withania somnifera using gel-filtration and ion-exchange chromatographies. The WSG is an acidic glycoprotein. Its molecular mass as determined by SDS-PAGE was 27kDa. It neutralized the enzyme activity and pharmacological properties such as cytotoxicity, edema, and myotoxicity of a multi-toxic Indian cobra venom phospholipase (NNXIa-PLA) but failed to neutralize the neurotoxicity. The glycan part of the molecule does not appear to be involved in any of the pharmacological properties studied. The results suggest that the neutralization of the pharmacological effects of the toxic phospholipase is brought about by inhibition of the enzyme activity by formation of a complex between the WSG and the toxic phospholipase. We report the purification and characterization of a glycoprotein phospholipase A inhibitor from Withania somnifera, medicinal plant.  相似文献   

11.
Different parts of plant species belonging to Solanaceae and Fabaceae families were screened for L-asparaginase enzyme (E.C.3.5.1.1.). Among 34 plant species screened for L-asparaginase enzyme, Withania somnifera L. Was identified as a potential source of the enzyme on the basis of high specific activity of the enzyme. The enzyme was purified and characterized from W. Somnifera, a popular medicinal plant in South East Asia and Southern Europe. Purification was carried out by a combination of protein precipitation with ammonium sulfate as well as Sephadex-gel filtration. The purified enzyme is a homodimer, with a molecular mass of 72±0.5 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresisand size exclusion chromatography. The enzyme has a pH optimum of 8.5 and an optimum temperature of 37℃. The Km value for the enzyme is 6.1×10-2 mmol/L. This is the first report for L-asparaginase from W. Somnifera, a traditionally used Indian medicinal plant.  相似文献   

12.
The low flow state that results from ischemia and reperfusion injury is a potentially reversible process that is important in numerous clinical situations. However, the point in time during the course of reperfusion where tissue injury becomes irreversible is unknown. This experiment evaluated the continuum of tissue damage in skeletal muscle after ischemic insult by quantifying the number of flowing capillaries and percentage muscle necrosis in a male Wistar rat skeletal muscle model. A gracilis muscle flap was raised on the vascular pedicle of 39 male Wistar rats and examined at 832x using intravital videomicroscopy. The numbers of flowing capillaries in five consecutive high-power fields were counted for baseline values. The flap was then subjected to 4 hours of global ischemia (except in sham animals, n = 7) by placing a microvascular clamp on the pedicle artery and vein. Upon reperfusion, flowing capillaries were counted in the same five high-power fields at intervals of 5, 15, 30, and 60 minutes, then at 2 to 8 (1-hour intervals), 24, and 48 hours. The gracilis muscle was then harvested at these intervals during reperfusion and assessed for viability. Compared with baseline, flowing capillaries from the ischemia and reperfusion group (mean +/- SEM) decreased significantly in the first 8 hours of reperfusion (7.7 +/- 0.2 to 3.2 +/- 0.3, p < 0.001) with minimal change noted from 8 to 48 hours. Percentage muscle necrosis increased progressively in ischemia and reperfusion preparations from 1 to 7 hours of reperfusion (16.5 +/- 2.6 percent to 38.9 +/- 1.2 percent, p < 0.001). No significant change in muscle necrosis in the ischemia and reperfusion group was noted between 7 and 48 hours. Sham preparations showed no change in the number of flowing capillaries through 3 hours of reperfusion, with a slight decrease at 24 hours. This rat gracilis microcirculation skeletal muscle model demonstrates a heterogeneous reperfusion injury. The decrease in flowing capillaries correlated with the increase in percentage necrosis and appeared to stabilize at the 7- to 8-hour interval. This finding may have important implications for the timing of interventions aimed at minimizing tissue damage from ischemia-reperfusion.  相似文献   

13.
Ayurvedic medicines prepared in India consist of Withania somnifera roots as one of the main ingredients. It is consumed as a dietary supplement around the world. The leaves of W. somnifera were used in the treatment of tumors and inflammation in several Asian countries. We have isolated twelve withanolides such as withaferin A (1), sitoindoside IX (2), 4-(1-hydroxy-2, 2-dimethylcyclpropanone)-2, 3-dihydrowithaferin A (3), 2, 3-dihydrowithaferin A (4), 24, 25-dihydro-27-desoxywithaferin A (5), physagulin D (1-->6)-beta-D-glucopyranosyl- (1-->4)-beta-D-glucopyranoside (6), 27-O-beta-D-glucopyranosylphysagulin D (7), physagulin D (8), withanoside IV (9), and 27-O-beta-D-glucopyranosylviscosalactone B (10), 4, 16-dihydroxy-5beta, 6beta-epoxyphysagulin D (11), viscosalactone B (12) from the leaves of this species. Compounds 1-12 and diacetylwithaferin A (13) were tested for their antiproliferative activity on NCI-H460 (Lung), HCT-116 (Colon), SF-268 (Central Nervous System; CNS and MCF-7 (Breast) human tumor cell lines. The inhibitory concentration to afford 50% cell viability (IC50) for these compounds was determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. Withaferin A and its derivatives exhibited inhibitory concentrations (50%) ranging from 0.24 +/- 0.01 to 11.6 +/- 1.9 microg/mL. Viscosalactone B (12) showed the 50% inhibition at concentrations ranging from 0.32 +/- 0.05 to 0.47 +/- 0.15 microg/mL whereas its 27-O-glucoside derivative (10) exhibited IC50 between 7.9 +/- 2.9 and 17.3 +/- 3.9 microg/ml. However, Physagulin D type withanolides showed either weak or no activity at 30 microg/mL. Therefore, incorporation of withanolides in the diet may prevent or decrease the growth of tumors in human.  相似文献   

14.
In vitro studies were initiated with Withania somnifera (L.) Dun. for rapid micropropagation of selected chemotypes using nodes, internodes, hypocotyls and embryo explants. Direct regeneration of shoot buds was observed in MS basal medium supplemented with various concentrations of either benzyladenine (BA) or thidiazouron (TDZ) depending on the explant. Nodal explants formed multiple shoots both from pre-existing and de novo buds on Murashige and Skoog's medium (MS) containing 0.1–5.0 mg l−1 BA and a ring of de novo shoot buds on MS medium containing 0.2 and 0.3 mg l−1 TDZ. Internodal explants formed shoot buds on MS with 1.0 and 5.0 mg l−1 BA while the hypocotyl explants gave rise to multiple shoots only on MS with 0.5 mg l−1 BA. Isolated embryos gave rise to many shoot buds on MS with 0.2 and 0.3 mg l−1 TDZ. The shoot buds elongated and rooted either on MS medium with 0.01 mg l−1 BA or on half strength MS medium lacking growth regulators, which depended upon the growth regulator used in the shoot bud induction medium. Except for the embryo-derived plantlets, all other plantlets could be acclimatized with 100% success. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

15.
Flavonoids are a large class of phenylpropanoid-derived secondary metabolites, which are usually glycosylated by UDP-glycosyltransferases with one or more sugar groups. Here, we report the cloning and biochemical characterization of a flavonoid glycosyltransferase gene from Withania somnifera (WsGT), which is an important medicinal plant used in Ayurvedic formulations. Using PCR primers, designed for a highly conserved region of previously reported glycosyltransferases, we were able to isolate the corresponding fragment of the WsGT gene. Rapid amplification of cDNA ends (RACE) was then employed to isolate full-length cDNA, which had an open reading frame of 1,371 bp that encode for 456 amino acids. Phylogenetic analysis indicated that WsGT was similar to that of family 1 GT-B glycosyltransferase. Biochemical analysis revealed that WsGT interacts with UDP-glucose and was capable of regiospecifically glycosylating flavonoid-7-ols, such as apigenin, naringenin, luteolin, diadzein and genistein. Expression profiling studies showed that WsGT was highly expressed in young and mature leaves of W. somnifera. Furthermore, exposure to salicylic acid enhanced the expression of WsGT in the leaves and heat shock treatment resulted in decreased expression of WsGT after an initial increase. This may suggest the role of WsGT in response to abiotic/biotic stresses.  相似文献   

16.
Venom hyaluronidases help in rapid spreading of the toxins by destroying the integrity of the extra-cellular matrix of the tissues in the victims. A hyaluronidase inhibitor (WSG) is purified from a folk medicinal plant, Withania somnifera. The glycoprotein inhibited the hyaluronidase activity of cobra (Naja naja) and viper (Daboia russelii) venoms, which was demonstrated by zymogram assay and staining of the skin tissues for differential activity. WSG completely inhibited the activity of the enzyme at a concentration of 1:1 w/w of venom to WSG. Thus we are able to demonstrate that the glycoprotein inhibits hyaluronidase activity of the venoms. External application of the plant extract as an antidote in rural parts of India to snakebite victims appears to have a scientific basis.  相似文献   

17.
Squalene synthase (SQS: EC 2.5.1.21) is a potential branch point regulatory enzyme and represents the first committed step to diverge the carbon flux from the main isoprenoid pathway towards sterol biosynthesis. In the present study, cloning and characterization of Withania somnifera squalene synthase (WsSQS) cDNA was investigated subsequently followed by its heterologous expression and preliminary enzyme activity. Two different types of WsSQS cDNA clones (WsSQS1and WsSQS2) were identified that contained an open reading frames of 1,236 and 1,242 bp encoding polypeptides of 412 and 414 amino acids respectively. Both WsSQS isoforms share 99 % similarity and identity with each other. WsSQS deduced amino acids sequences, when compared with SQS of other plant species, showed maximum similarity and identity with Capsicum annuum followed by Solanum tuberosum and Nicotiana tabacum. To obtain soluble recombinant enzymes, 24 hydrophobic amino acids were deleted from the carboxy terminus and expressed as 6X His-Tag fusion protein in Escherichia coli. Approximately 43 kDa recombinant protein was purified using Ni-NTA affinity chromatography and checked on SDS-PAGE. Preliminary activity of the purified enzymes was determined and the products were analyzed by gas chromatograph-mass spectrometer (GC-MS). Quantitative real-time PCR (qRT-PCR) analysis showed that WsSQS expresses more in young leaves than mature leaves, stem and root.  相似文献   

18.
Machiah DK  Gowda TV 《Biochimie》2006,88(6):701-710
A post-synaptic neurotoxic phospholipase A(2) (PLA(2)) has been purified from Indian cobra Naja naja venom. It was associated with a peptide in the venom. The association was disrupted using 8 M urea. It is denoted to be a basic protein by its behavior on both ion exchange chromatography and electrophoresis. It is toxic to mice, LD(50) 1.9 mg/kg body weight (ip). It is proved to be post-synaptic PLA(2) by chymographic experiment using frog nerve-muscle preparation. A glycoprotein, (WSG) was isolated from a folk medicinal plant Withania somnifera. The WSG inhibited the phospholipase A(2) activity of NN-XIa-PLA(2,) isolated from the cobra venom, completely at a mole-to-mole ratio of 1:2 (NN-XIa-PLA(2): WSG) but failed to neutralize the toxicity of the molecule. However, it reduced the toxicity as well as prolonged the death time of the experimental mice approximately 10 times when compared to venom alone. The WSG also inhibited several other PLA(2) isoforms from the venom to varying extent. The interaction of the WSG with the PLA(2) is confirmed by fluorescence quenching and gel-permeation chromatography. Chemical modification of the active histidine residue of PLA(2) using p-brophenacyl bromide resulted in the loss of both catalytic activity as well as neurotoxicity of the molecule. These findings suggest that the venom PLA(2) has multiple sites on it; perhaps some of them are overlapping. Application of the plant extract on snakebite wound confirms the medicinal value associated with the plant.  相似文献   

19.
The lipophilic antioxidant Trolox C, a vitamin E analog, was administered to isolated, buffer-perfused rabbit hearts subjected to 25 min of global stop-flow ischemia and 30 min of reperfusion. In six hearts, Trolox C (200 microM) was infused for 15 min immediately prior to ischemia and for the first 15 min of reperfusion. Six control hearts received only vehicle. Gas chromatography analysis confirmed that effective myocardial levels of Trolox were attained. At 30 min reperfusion, the recovery of left ventricular developed pressure was 56 +/- 3% of baseline in control hearts versus 70 +/- 4% in Trolox-treated hearts (p < .01). There was also significant improvement in recovery of Trolox-treated hearts in diastolic pressure and both maximum and minimum values of the first derivative of left ventricular pressure (dP/dt). Creatine phosphokinase release into the coronary effluent at 30 min of reperfusion was 16.5 +/- 8.4 IU/min in untreated and 6.3 +/- 1.0 IU/min (p < .05) in Trolox-treated hearts. Thus Trolox C, a lipophilic antioxidant, attenuated myocardial injury during stop-flow ischemia and reperfusion.  相似文献   

20.
We studied the influence of Withania somnifera (Ws) root extract (100 mg/kg body weight) on parkinsonism induced by 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine (MPTP; i.p, 20 mg/kg body weight for 4 days), via the analysis of behavioral features and the oxidant-antioxidant imbalance in the midbrain of mice. A significant alteration in behavior, increased levels of thiobarbituric acid reactive substance (TBARS), and increased activities of superoxide dismutase (SOD) and catalase (CAT) were noticed in this region of brain in MPTP-treated mice. Oral treatment with the root extract resulted in a significant improvement in the mice’s behavoiur and antioxidant status, along with a significant reduction in the level of lipid peroxidation. The results indicated that at least part of the chronic stress-induced pathology may be due to oxidative stress, which is mitigated by Ws. Further studies are needed to assess the precise mechanism to support the clinical use of the plant as an antiparkinsonic drug.  相似文献   

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