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1.
The in-vitro antioxidant activities of different concentrations of the water, alcoholic, petroleum ether and ethyl acetate extracts of the dried leaves of Clerodendron colebrookianum Walp, and in-vivo antioxidant activity of the water extract was studied in experimental rat models. The results obtained from in-vitro lipid peroxidation induced by FeSO4-ascorbate in rat liver homogenate showed a significant inhibition of lipid peroxidation by different extracts of C. colebrookianum leaf. Water extracts at concentrations (w/v) of 1:30, 1:50, 1:200 and 1:1000 showed the strongest inhibitory activity over the other organic extracts, suggesting maximum antioxidant effect. Chronic feeding of the water extract to Wistar albino rats (both sexes, 150-200 g) in 1 or 2 g kg-1/day doses for 14 days significantly increased the ferric reducing ability of plasma by 19% and 40% on the seventh day, and by 45% and 57% on the fourteenth day of treatment, respectively. Thiobarbituric acid reactive substances (TBARS), as a marker of lipid peroxidation, and some cellular antioxidants (superoxide dismutase, catalase and reduced glutathione) were estimated in heart, liver and kidney. There was a significant reduction in hepatic and renal TBARS with both the doses, without any change in myocardial TBARS. There was no change in the level of antioxidants in heart, liver and kidney, except for the hepatic superoxide dismutase. The findings of this study showed that the leaf extract of C. colebrookianum increased the antioxidant capacity of blood and had an inhibitory effect on the basal level of lipid peroxidation of liver and kidney. This lends scientific support to the therapeutic use of the plant leaves, as claimed by the tribal medicine of North-East India.  相似文献   

2.
The antioxidative effects of mulberroside A and oxyresveratrol obtained from Mori Cortex were examined. Mulberroside A and oxyresveratrol showed an inhibitory effect against FeSO4/H2O2-induced lipid peroxidation in rat microsomes and a scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical. The anti-inflammatory effects of mulberroside A and oxyresveratrol using the carrageenin-induced model of inflammation were investigated in rats. Mulberroside A and oxyresveratrol significantly reduced paw edema. To investigate the mechanism of the anti-inflammatory action of these compounds, we examined the effects of oxyresveratrol on lipopolysaccharide (LPS)-induced responses in murine macrophage cell line RAW 264.7. Exposure of LPS-stimulated cells to oxyresveratrol inhibited nitrite accumulation in the culture medium. Oxyresveratrol also inhibited the LPS-stimulated increase of inducible nitric oxide synthase (iNOS) expression in a concentration-dependent manner; however, it had little effect on iNOS enzyme activity, suggesting that the inhibitory activity of oxyresveratrol is mainly due to the inhibition of iNOS expression rather than iNOS enzyme activity. Oxyresveratrol significantly inhibited LPS-evoked nuclear translocation of NF-kappaB and cyclooxygenase-2 (COX-2) activity in RAW 264.7 cells. The results suggest that the anti-inflammatory properties of oxyresveratrol might be correlated with inhibition of the iNOS expression through down-regulation of NF-kappaB binding activity and significant inhibition of COX-2 activity.  相似文献   

3.
In traditional medicine the fresh leaves and juice of Sedum telephium L. are used as wound-healing promoters. Cell adhesion represents a primary event in wound repair and in tissue homeostasis, and therefore we have investigated the effect of Sedum juice and its main fractions, polysaccharides and flavonols, on human fibroblast (MRC5) adhesion to fibronectin and laminin. Our findings revealed that total Sedum juice strongly inhibited cell adhesion to laminin and fibronectin (EC50 1.03+/-0.12 mg mL(-1)). This anti-adhesive feature was concentrated mainly in the two polysaccharide fractions (EC50 values comprised between 0.09 and 0.44 mg mL(-1)). The flavonol fractions did not seem to contribute to this effect. A first attempt to elucidate the polysaccharide-related anti-adhesive feature of Sedum juice was also performed. The results confirmed that natural polysaccharides, with chemical structures different from heparin, were able to interfere with integrin-mediated cell behaviour and they contributed to the outstanding effects of Sedum juice and to the role of polysaccharides in cell-matrix interaction.  相似文献   

4.
目的对费菜(Sedum aizoon L.)茎叶正丁醇萃取物的化学成分进行研究。方法采用硅胶柱色谱、ODS柱色谱、Sephadex LH-20柱色谱和HPLC分离纯化,依据理化性质和光谱数据确定化合物的结构。结果从费菜茎叶体积分数为70%的乙醇提取物的正丁醇层分离鉴定了13个单体化合物,分别为苯乙醇-O-β-D-葡萄糖苷(benzylethyl-O-β-D-glucopyranoside,1)、vanilloloside(2)、苯乙醇-O-β-D-吡喃木糖-(1→2)-β-D-吡喃葡萄糖苷(benzylethyl-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside,3)、1-氰基-3-O-β-D-吡喃葡萄糖-(Z)-1-甲基-1-丙烯(1-cyano-3-O-β-D-glucopyranosyloxy-(Z)-1-methyl-1-propene,4)、7-O-没食子酰-D-景天庚酮糖(7-O-galloyl-D-sedoheptulose,5)、表百脉根苷(epilotaustralin,6)、蒺藜酸(terrestric acid,7)、 cinnamoside(8)、inotodisaccharide(9)、β-D-glucopyranosyl-(1→3)-arbutin(10)、3-O-[α-L-arabinopyranosyl(1→6)-β-D-glucopyranosyl]-5-hydroxymegastigma-6,7-dien-9-one(11)、roseoside(12)and vomifoliol-3′-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside(13)。结论化合物5-13为首次从景天属植物中分离得到。  相似文献   

5.
费菜茎叶的化学成分   总被引:1,自引:0,他引:1  
目的对费菜(Sedum aizoonL.)茎叶的化学成分进行研究。方法采用硅胶柱色谱?ODS柱色谱、Sephadex LH-20柱色谱和HPLC柱色谱分离纯化,依据理化性质和光谱数据确定化合物的结构。结果从费菜茎叶体积分数为70%的乙醇提取物的乙酸乙酯层中分离得到11个化合物,分别鉴定为:山柰酚(kaempferol,1)、槲皮素(quercetin,2)、杨梅素(myricetin,3)、木樨草素(luteolin,4)、山柰酚-3-O-α-L-鼠李糖苷(kaempferol-3-O-α-L-rhamnosid,5)、草质素-8-O-α-D-来苏糖苷(herbace-tin-8-O-α-D-lyxoside,6)、草质素-8-O-β-D-木糖苷(herbacetin-8-O-β-D-xylopyranoside,7)、对羟基苯酚(1,4-benzenediol,8)、没食子酸(gallic acid,9)、没食子酸甲酯(methyl gallate,10)、β-谷甾醇(β-sitostero,11)。结论化合物4、7、8为首次从该植物中分离得到,化合物5、6为首次从本属植物中得到。  相似文献   

6.
In-vitro and in-vivo immunomodulatory effects of syringin   总被引:2,自引:0,他引:2  
Syringin was found to possess immunomodulatory activity by which it inhibited the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum through suppression of C3-convertase of the classical complement. In this study, we examined its in-vitro and in-vivo activity on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, CD4+ T cell and CD8+ cytotoxic T cell (CTLL-2) proliferation, and croton oil-, arachidonic acid- and fluorescein-isothiocynate (FITC)-induced mouse ear oedema model. Syringin significantly inhibited both TNF-alpha production from lipopolysaccharide (LPS)-stimulated RAW264.7 cells and CD8+ T cell (CTLL-2) proliferation in a dose-dependent manner, whereas neither NO production nor CD4+ T cell proliferation were blocked even by high concentrations of syringin. In the invivo experiments, syringin also significantly suppressed FITC-induced ear oedema in mice but not the ear oedema induced by croton or arachidonic acid. These results suggest that syringin may be implicated as an immunomodulator having an anti-allergic effect rather than an anti-inflammatory effect. The anti-allergic effect of syringin seems to be due, in part, to inhibition of TNF-alpha production and cytotoxic T cell proliferation.  相似文献   

7.
In attempt to increase the accumulation of topotecan in tumours and improve its anti-cancer activity, PEGylated liposome (H-PEG) containing topotecan was prepared. The in-vitro cytotoxicity, in-vivo biodistribution pattern and anti-tumour effect of H-PEG were studied systemically. Compared with free topotecan or conventional liposome (H-Lip), H-PEG improved the cytotoxic effect of topotecan against human ovarian carcinoma A2780 and human colon carcinoma HCT-8 cells. The IC50 value (concentration leading to 50% cell-killing) of H-PEG decreased 5 fold (P<0.01) and 9 fold (P<0.01) against A2780 and HCT-8 cells compared with H-Lip, respectively. The results of biodistribution studies in sarcoma S(180) tumour-bearing mice showed that liposomal encapsulation increased the concentration of total topotecan and the ratio of lactone form in plasma. H-PEG resulted in a 70-fold and 3.7-fold increase in AUC(0-->24 h) compared with free topotecan and H-Lip, respectively. Moreover, H-PEG increased the accumulation of topotecan in tumours and the relative tumour uptake ratio compared with free topotecan was 5.2, and higher than that of H-Lip. The anti-cancer effect studies in murine heptocarcinoma H(22) tumour-bearing mice showed that H-PEG improved the therapeutic efficiency of topotecan and decreased the toxicity of topotecan to a certain extent compared with H-Lip. These results indicated that PEG-modified liposome might be an efficient carrier of topotecan.  相似文献   

8.
The species Campomanesia adamantium (Cambess.) O. Berg is native to the Brazilian Cerrado and has medicinal properties. Currently, researchers have been working on its domestication, bringing the possibility of its use in the elaboration of sustainable products. In this context, the objective was to analyze the extraction yield at concentrations of 2% (m/v) and 5% (m/v) and the photoprotective effect of different extracts of C. adamantium leaves obtained with different concentrations of ethanol and water, also, determine the preparation method with the greatest potential for phytocosmetic applications. Spectrophotometric methods were used to determine the levels of phenolic compounds, flavonoids, and antioxidant activity of the samples, as well as the sun protection factor (SPF), critical wavelength (λc), and UVA/UVB of the samples, besides the profile in the UV/Vis, infrared and UHPLC-DAD. The extraction concentration of 2% (m/v) showed yields significantly higher than 5% (m/v) by the independent t-test of the extracting solvent. Infrared scanning demonstrated the presence of functional groups associated with phenolic compounds. Through polynomial regression, it was found that ethanol concentrations between 75 and 100% are ideal for obtaining extracts rich in phenolic compounds, with antioxidant and photoprotective potential, but the concentration of 50% was more adequate to obtain a greater yield. Gallic acid, rutin, and 5,7-dihydroxy-6-methylflavanone were identified. All proportions of ethanol:water resulted in critical wavelength between 375 and 379 nm, and UVA/UVB ratio between 1.17 ± 0.01 and 1.53 ± 0.07 which indicate a good distribution of UV absorption and possible photoprotection in the UVA region.  相似文献   

9.
Quercetin is well known to possess the strongest protective effect against UV light-induced lipoperoxidation. However, the absolute water insolubility of quercetin is a key step that may limit its bioavailability and, thus, its 'in vivo' employment as a photoprotective agent. The aim of the present paper was to evaluate 'in vitro' the antioxidant and photoprotective properties and the interaction with model membranes of three new semisynthetic quercetin derivatives, quercetin-3-O-acetate (Q-ac), quercetin-3-O-propionate (Q-pr) and quercetin-3-O-palmitate (Q-pal), obtained by esterification of the C-3 OH function with an aliphatic side-chain of different length. The antioxidant activity of quercetin and of its three esters was assessed in two 'in vitro' experimental models: (a) the bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical; (b) UV radiation-induced peroxidation in multilamellar vesicles (MLVs). Differential scanning calorimetry on dimyristoylphosphatidylcholine MLVs and unilamellar vesicles was employed to investigate the interaction of the drugs tested with model membranes. Finally, the stability following UV light exposure and the lipophilicity and water solubility of quercetin and its three esters were examined. The findings obtained demonstrated that the esterification with an opportune aliphatic side chain of the OH function located at the C-3 position allows the production of new quercetin derivatives, which may be good candidates as photoprotective agents. In particular, one could speculate that the esterification with a short side-chain (such as in Q-ac and Q-prop) provides the suitable chemico-physical features not only to maintain the antioxidant and photoprotective effectiveness of the parent drug, but also to be able to migrate through the aqueous environment and to interact with and cross phospholipid membranes.  相似文献   

10.
The effects of various extracts from oriental medicinal herbs on mast cell-mediated allergic reactions have been investigated. Among the extracts, Arecae semen was the most potent inhibitor of antigen-induced degranulation in RBL-2H3 mast cells. A. semen inhibited DNP-BSA- and compound 48/80-induced degranulation in RBL-2H3 mast cells with IC(50) values of approximately 53 and 52 microg mL(-1), respectively, and inhibited compound 48/80-induced systemic anaphylaxis by 46% at 300 mg kg(-1) in mice. A. semen also inhibited the expression of TNF-alpha and the activation of mitogen activated protein kinase, ERK1/2, which is critical for the production of inflammatory cytokines in mast cells, as indicated by the suppression of the activating phosphorylation of ERK1/2. These results suggest that A. semen may be useful for the treatment of various immediate and delayed allergic diseases.  相似文献   

11.
The aim of the present study was to investigate the antioxidant activity of aqueous extracts of Toona sinensis (TS; 0-100 microg/mL) and gallic acid (0-50 microg/mL), with the purified natural phenolic components evaluated using different antioxidant models. It was found that the TS extracts and gallic acid possess effective antioxidant activity against various oxidative systems in vitro, including the scavenging of free and superoxide anion radicals, reducing power, and metal chelation. However, antioxidant activity in terms of metal chelation was not observed for the gallic acid. Moreover, TS extracts and gallic acid appear to possess powerful antioxidant properties with respect to oxidative modification of human LDL induced by CuSO4, AAPH or sodium nitroprusside, as assessed by the relative electrophoretic mobility, TBARS formation, and cholesterol degradation of oxidized LDL. Furthermore, AAPH-induced oxidative hemolysis, lipid peroxidation, and decline in superoxide dismutase (SOD) activity in human erythrocytes were prevented by both the TS extracts and the gallic acid. Our findings suggest that T. sinensis may act as a chemopreventative agent, providing antioxidant properties and offering effective protection from atherogenesis.  相似文献   

12.
Three successive extracts of Clerodendrum infortunatum L. leaves have been studied for their potential as antioxidants in 1,1-diphenyl-2-picrylhydrazyl (DPPH) model. The scavenging activity of ethanol extract was found to be high when compared to petroleum ether and chloroform extracts. Hence, it was selected to evaluate the beneficial properties using in vitro and in vivo models. The antioxidant and its protective effects against CCl(4) induced oxidative stress in rats were significantly high. Further, to validate the traditional therapeutic claim, wound healing activity of the plant extracts was also carried out. Among the three extracts tested the petroleum ether and ethanol extracts exhibited a significant response. The presence of high antioxidant and pharmacological properties correlates to the total phenolic contents in the plant Clerodendrum infortunatum L.  相似文献   

13.
The aim of this study was to evaluate the in-vitro release rates and in-vivo effectiveness of a controlled release, intravaginal dosage form of bromocriptine mesilate. The dimeticone (poly(dimethylsiloxane)) elastomer vaginal ring contained 3 mg bromocriptine mesilate and low molecular weight gelatin in a ratio of 1:3, and 10% propylene glycol. The daily release rate of the drug was designed to be 10% of the total administered dose and was confirmed with release experiments under sink conditions. The effect of the vaginal ring preparation on plasma prolactin level in the rabbit was investigated over a 10-day period. The results showed that the vaginal ring of bromocriptine mesilate significantly decreased the plasma prolactin level of the test group (P < 0.001-0.05) compared with the control and placebo groups. It was concluded that bromocriptine mesilate was effectively absorbed from rabbit vagina and that this controlled release intravaginal ring preparation of bromocriptine mesilate was effective in decreasing the plasma prolactin level in rabbits for ten days.  相似文献   

14.
15.
An increasing demand for natural additives has shifted the attention from synthetic to natural antioxidants and antifungal agents. This study was carried out to evaluate the antifungal and antioxidant activities of methanol, chloroform, and aqueous extracts of Annona squamosa Linn. leaves. The antifungal activities of all extracts of A. squamosa leaves against five different strains of fungi (Alternaria alternata, Candida albicans, Fusarium solani, Microsporum canis, and Aspergillus niger) were evaluated by the agar well diffusion method and the minimum inhibitory concentration of each extract was assessed by antifungal susceptibility using the broth microdilution method. The antioxidant potential of each extract was determined by free radicals (1,1-diphenyl-2-picrylhydrazyl, nitric oxide, and hydrogen peroxide) scavenging activity and reducing power property of A. squamosa leaves. Both organic and aqueous extracts were found to express dose-dependent inhibition against all tested fungi strains in both agar well diffusion and broth dilution methods. The free radical scavenging activity and reducing power property of all extracts were found to be concentration dependent, with the methanol extract exhibiting higher antioxidant activity than the chloroform extract, which was more effective than the aqueous extract of A. squamosa leaves. Results of phytochemical analysis of extracts showed the presence of glycosides, saponins, tannins, flavonoids, phenols, etc. The results obtained from in vitro studies of antifungal and antioxidant activities clearly suggest that the methanol, chloroform, and aqueous extracts of A. squamosa leaves possess antifungal and antioxidant activity.  相似文献   

16.
Buprenorphine is a mu-opioid receptor partial agonist with enhanced safety and comparable efficacy to methadone for treatment of opioid dependence. The sublingual formulation of buprenorphine, approved for treatment of opioid dependence, produces variable buprenorphine blood levels and requires frequent dosing that limits patient compliance. To achieve stable buprenorphine levels that may improve patient outcome, an implantable sustained buprenorphine delivery system was developed. Each implant consists of ethylene vinyl acetate copolymer and 90 mg buprenorphine HCl, and measures 26 mm in length and 2.4 mm in diameter. Steady-state release in-vitro was 0.5 mg/implant/day. In-vivo pharmacokinetics and safety were examined for up to 52 weeks in beagle dogs receiving 8, 16 or 24 subcutaneous implants. Plasma buprenorphine concentrations correlated with the number of implants administered. Peak buprenorphine concentrations were generally reached within 24 h after implantation. Steady-state plasma levels were attained between 3 and 8 weeks, and were maintained for study duration, with a calculated mean release rate of 0.14+/-0.04 mg/implant/day. There were no test-article-related adverse effects. This delivery system can provide long-term stable systemic buprenorphine levels, and may increase patient compliance, thereby improving outcome for opioid-dependent patients.  相似文献   

17.
Sedum telephium ssp. maximum is a medicinal plant that possesses anti-inflammatory, analgesic and keratolytic properties. We investigated the anti-inflammatory activity of its methanolic extract (STME) in rat peritoneal macrophages (MPhis) stimulated with lipopolysaccharide from Salmonella enteritidis. After stimulation with 10 microg/ml of LPS, MPhis were coincubated with different doses of STME (8, 16 and 32 microg/ml) or RPMI medium alone using different times of incubation. STME reduced levels of tumor necrosis factor-alpha, both mRNA and its protein, and significantly decreased IL-1beta and IL-6 production. Moreover, STME inhibited inducible nitric oxide synthase expression and blunted nitrite release and inhibited both extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase activation in lipopolysaccharide-stimulated MPhis. Data show that STME might be useful as a potential anti-inflammatory agent.  相似文献   

18.
Our objectives were to study the biological activity of a novel gemcitabine-cardiolipin conjugate (NEO6002) and compare that with gemcitabine. Cytotoxicity in vitro was determined against several gemcitabine-sensitive parental and gemcitabine-resistant cancer cell lines using the sulforhodamine B assay. The in vivo toxicity was examined by changes in body weight and hematologic indices of conventional mice. Immunodeficient SCID mice bearing P388 and BxPC-3 tumor xenografts were used to evaluate the in-vivo therapeutic efficacy. Both NEO6002 and gemcitabine showed pro-apoptotic and cytotoxic effects against all gemcitabine-sensitive cell lines tested. Unlike gemcitabine, the cytotoxicity of NEO6002 was independent of nucleoside transporter (NT) inhibitors, indicating a different internalization route of NEO6002. The conjugate demonstrated a favorable activity not only in ARAC-8C, a NT-deficient gemcitabine-resistant human leukemia cell line, but also in several other gemcitabine-resistant cell lines. At the in-vivo level, a comparative toxicity study showed a significant body weight loss and a decrease in white blood cell counts in gemcitabine-treated mice, whereas the influence of NEO6002 was mild. Treatment of NEO6002 at 27 micromol/kg increased the median survival of CD2F1 mice bearing P388 cells by up to 73%, while at the same doses and schedule of gemcitabine resulted in toxic deaths of all treated mice. At a dose of 18 micromol/kg, NEO6002 inhibited the growth of BxPC-3 xenografts by 52%, while only 32% of tumor inhibition was achieved with gemcitabine. We conclude that NEO6002 may be an effective chemotherapeutic agent with improved tolerability and can potentially circumvent NT-deficient, gemcitabine-resistant tumors.  相似文献   

19.
Various in-vitro and in-vivo methods for evaluation of the duration of antibacterial activity were compared using a controlled-release polyurethane matrix developed for the prevention of surface bacterial adhesion and growth. Cefadroxil was incorporated into this polyurethane matrix by a solvent casting method before the matrix was coated with polyurethane in tetrahydrofuran solution. The release of cefadroxil from the matrix into distilled water at 37 degrees C was measured by HPLC. The morphological change of matrices before and after release studies was investigated by scanning electron microscopy (SEM). The duration of antimicrobial activity of the matrix against Escherichia coli and Staphylococcus aureus was evaluated by measuring the diameters of the inhibition zone and the optical density of the broth. The matrices were also implanted subcutaneously in rats and the duration of the antibacterial activity was determined by measuring the inhibition zone. The results showed that duration of antibacterial activity of the polyurethane matrix was successfully determined in-vitro by these methods, and the results differed from the conventional in-vitro release study. It was also possible to determine the duration of action of the matrix in-vivo by implanting the matrix in rats, and then measuring the antibacterial activity of the matrix at predetermined time intervals. While a good correlation was observed between the in-vitro and in-vivo methods used in this study to evaluate the duration of the antibacterial activity of the polymeric matrix, the conventional in-vitro release study did not coincide with these results.  相似文献   

20.
景天三七的现代研究进展   总被引:1,自引:0,他引:1  
刘学杰  王姣  仲英 《齐鲁药事》2007,26(5):295-296
景天三七是传统的药用植物,本文主要对其化学成分、药理作用、毒性试验、临床民间应用、目前的开发状况等做系统的阐述。  相似文献   

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