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1.
Ju EM  Lee SE  Hwang HJ  Kim JH 《Life sciences》2004,74(8):1013-1026
The antioxidant and anticancer properties of a medicinal plant, Betula platyphylla var. japonica were investigated. The total methanol extract of B. platyphylla var. japonica had protective effects against hydrogen peroxide (H2O2) in the Chinese hamster lung fibroblast (V79-4) cell line and induced apoptotic cell death in human promyelocytic leukemia (HL-60) cells, a cancer cell line. B. platyphylla var. japonica extract significantly increased cell viability against H2O2. The extract also showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (IC50 2.4 microg/ml) and lipid peroxidation inhibitory activity (IC50 below 4.0 microg/ml). Furthermore, B. platyphylla var. japonica extract reduced the number of V79-4 cells arrested in G2/M in response to H2O2 treatment and increased the activities of several cellular antioxidant enzymes, including superoxide dismutase, catalase and glutathione peroxidase. Treatment with B. platyphylla var. japonica extract induced cytotoxicity and apoptosis in HL-60 cells, as shown by nucleosomal DNA fragmentation, increases in the subdiploid cell population, and fluorescence microscopy. B. platyphylla var. japonica extract gradually increased the expression of pro-apoptotic Bax and led to the activation of caspase-3 and cleavage of PARP. These findings suggest that B. platyphylla var. japonica exhibits potential antioxidant and anticancer properties.  相似文献   

2.
Plants are still to be explored for new anti-cancer compounds because overall success in cancer treatment is still not satisfactory. As a new possible source for such compounds, the lichens are recently taking a great attention. We, therefore, explored both the genotoxic and anti-growth properties of lichen species Parmelia sulcata Taylor. The chemical composition of P. sulcata was analyzed with comprehensive gas chromatography–time of flight mass spectrometry. Anti-growth effect was tested in human breast cancer cell lines (MCF-7 and MDA-MB-231) by the MTT and ATP viability assays, while the genotoxic activity was studied by assays for micronucleus, chromosomal aberration and DNA fragmentation in human lymphocytes culture. Cell death modes (apoptosis/necrosis) were morphologically assessed. P. sulcata inhibited the growth in a dose-dependent manner up to a dose of 100 μg/ml and induced caspase-independent apoptosis. It also showed genotoxic activity at doses (>125 μg/ml) higher than that required for apoptosis. These results suggest that P. sulcata may induce caspase-independent apoptotic cell death at lower doses, while it may be genotoxic at relatively higher doses.  相似文献   

3.
Spondias pinnata, a commonly distributed tree in India, previously proven for various pharmacological properties and also reported for efficient anti-oxidant, free radical scavenging and iron chelating activity, continuing this, the present study is aimed to investigate the role of 70 % methanolic extract of S. pinnata bark (SPME) in promoting apoptosis in human lung adenocarcinoma cell line (A549) and human breast adenocarcinoma cell line (MCF-7). These two malignant cell lines and a normal cell line were treated with increasing concentrations of SPME and cell viability is calculated. SPME showed significant cytotoxicity to both A549 and MCF-7 cells with an IC50 value of 147.84 ± 3.74 and 149.34 ± 13.30 μg/ml, respectively, whereas, comparatively no cytotoxicity was found in normal human lung fibroblast cell line (WI-38): IC50 932.38 ± 84.44 μg/ml. Flow cytometric analysis and confocal microscopic studies confirmed that SPME is able to induce apoptosis in both malignant cell lines. Furthermore, immunoblot result proposed the pathway of apoptosis induction by increasing Bax/Bcl-2 ratio in both cell types, which results in the activation of the caspase-cascade and ultimately leads to the cleavage of Poly adeno ribose polymerase. For the first time this study proved the anticancer potential of SPME against human lung and breast cancer by inducing apoptosis through the modulation of Bcl-2 family proteins. This might take S. pinnata in light to investigate it for further development as therapeutic anticancer source.  相似文献   

4.
Expression of a Rhodococcus-derived oxygenase gene in Escherichia coli yielded indigo metabolites with cytotoxic activity against cancer cells. Bioactivity-guided fractionation of these indigo metabolites led to the isolation of trisindoline as the agent responsible for the observed in vitro cytotoxic activity against cancer cells. While the cytotoxicity of etoposide, a common anticancer drug, was dramatically decreased in multidrug-resistant (MDR) cancer cells compared with treatment of parental cells, trisindoline was found to have similar cytotoxicity effects on both parental and MDR cell lines. In addition, the cytotoxic effects of trisindoline were resistant to P-glycoprotein overexpression, one of the most common mechanisms of drug resistance in cancer cells, supporting its use to kill MDR cancer cells.  相似文献   

5.
Theileria annulata, a protozoan parasite of cattle and domestic buffaloes, is transmitted by ticks of the genus Hyalomma, and causes a disease named Mediterranean or tropical theileriosis. In this research 50 cattle naturally infected with Theileria annulata were treated with the extract of the plant Peganum harmala. The treatment was continued for 5 days, the dose of the extract being 5 mg/kg per day. After the treatment, 39 cattle responded to the treatment and recovered, but 11 did not respond to the treatment and died. The recovery rate of animals treated with the extract of the plant Peganum harmala was 78%.  相似文献   

6.
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8.
It is now widely accepted that dietary phytochemicals inhibit cancer progression and enhance the effects of conventional chemotherapy. In this report, we comparatively studied the cellular and molecular aspects of apoptosis induction by the methanolic extract of Baneh fruit skin in comparison to Doxorubicin (Dox), a well-known anticancer drug, in human breast cancer T47D cells. The MTT assay was used to determine the antiproliferative effects. The flow cytometric and microscopic analyses were done to evaluate the apoptosis induction. Furthermore, western blot analyses have been done to study the role of key molecular players of apoptosis including caspase 3 and PARP. The Baneh extract showed strong antiproliferative activity against T47D cells in a dose- and time-dependent manner that was comparable to and even stronger than Dox in certain concentrations. Analysis of Baneh-treated cells by flow cytometry and fluorescence microscopy indicated strong apoptosis induction and nuclear morphological alterations similar to or greater than Dox. Finally, molecular analysis of apoptosis by western blotting proved activation of caspase 3 followed by poly ADP ribose polymerase (PARP) cleavage more efficiently in Baneh than in Dox treated cancer cells. These findings indicate that Baneh extract contains phytochemicals which act as inhibitor of cell proliferation and inducer of apoptosis in human breast cancer T47D cells that makes it a potentially good candidate for new anticancer drug development.  相似文献   

9.
High-throughput screening of protein-protein and protein-peptide interactions is of high interest both for biotechnological and pharmacological applications. Here, we propose the use of the noncoded amino acids o-nitrotyrosine and p-iodophenylalanine as spectroscopic probes in combination with circular dichroism and fluorescence quenching techniques (i.e., collisional quenching and resonance energy transfer) as a means to determine the peptide orientation in complexes with SH3 domains. Proline-rich peptides bind SH3 modules in two alternative orientations, according to their sequence motifs, classified as class I and class II. The method was tested on an SH3 domain from a yeast myosin that is known to recognize specifically class I peptides. We exploited the fluorescence quenching effects induced by o-nitrotyrosine and p-iodophenylalanine on the fluorescence signal of a highly conserved Trp residue, which is the signature of SH3 domains and sits directly in the binding pocket. In particular, we studied how the introduction of the two probes at different positions of the peptide sequence (i.e., N-terminally or C-terminally) influences the spectroscopic properties of the complex. This approach provides clear-cut evidence of the orientation of the binding peptide in the SH3 pocket. The chemical strategy outlined here can be easily extended to other protein modules, known to bind linear sequence motifs in a highly directional manner.  相似文献   

10.
In this work, we describe the ability of living trophozoites of Giardia lamblia to hydrolyze extracellular ATP. In the absence of any divalent cations, a low level of ATP hydrolysis was observed (0.78 ± 0.08 nmol Pi × h−1 × 10−6 cells). The ATP hydrolysis was stimulated by MgCl2 in a dose-dependent manner. Half maximum stimulation of ATP hydrolysis was obtained with 0.53 ± 0.07 mM. ATP was the best substrate for this enzyme. The apparent Km for ATP was 0.21 ± 0.04 mM. In the pH range from 5.6 to 8.4, in which cells were viable, this activity was not modified. The Mg2+-stimulated ATPase activity was insensitive to inhibitors of intracellular ATPases such as vanadate (P-ATPases), bafilomycin A1 (V-ATPases), and oligomycin (F-ATPases). Inhibitors of acid phosphatases (molybdate, vanadate and fluoride) or alkaline phosphatases (levamizole) had no effect on the ecto-ATPase activity. The impermeant agent DIDS and suramin, an antagonist of P2 purinoreceptors and inhibitor of some ecto-ATPases, decreased the enzymatic activity in a dose-dependent manner, confirming the external localization of this enzyme. Besides ATP, trophozoites were also able to hydrolyse ADP and 5´ AMP, but the hydrolysis of these nucleotides was not stimulated by MgCl2. Our results are indicative of the occurrence of a G. lamblia ecto-ATPase activity that may have a role in parasite physiology.  相似文献   

11.
We have characterized a phosphatase activity present on the external surface of Leishmania amazonensis, using intact living parasites. This enzyme hydrolyzes the substrate p-nitrophenylphosphate (p-NPP) at the rate of 25.70+/-1.17 nmol Pi x h(-1) x 10(-7)cells. The dependence on p-NPP concentration shows a normal Michaelis-Menten kinetics for this ecto-phosphatase activity present a V(max) of 31.93+/-3.04 nmol Pi x h(-1) x 10(-7)cells and apparent K(m) of 1.78+/-0.32 mM. Inorganic phosphate inhibited the ecto-phoshatase activity in a dose-dependent manner with the K(i) value of 2.60 mM. Experiments using classical inhibitor of acid phosphatase, such as ammonium molybdate, as well as inhibitors of phosphotyrosine phosphatase, such as sodium orthovanadate and [potassiumbisperoxo(1,10-phenanthroline)oxovanadate(V)] (bpV-PHEN), inhibited the ecto-phosphatase activity, with the K(i) values of 0.33 microM, 0.36 microM and 0.25 microM, respectively. Zinc chloride, another classical phosphotyrosine phosphatase inhibitor, also inhibited the ecto-phosphatase activity in a dose-dependent manner with K(i) 2.62 mM. Zinc inhibition was reversed by incubation with reduced glutathione (GSH) and cysteine, but not serine, showing that cysteine residues are important for enzymatic activity. Promastigote growth in a medium supplemented with 1mM sodium orthovanadate was completely inhibited as compared to the control medium. Taken together, these results suggest that L. amazonensis express a phosphohydrolase ectoenzyme with phosphotyrosine phosphatase activity.  相似文献   

12.

Background

Clinical use of chemotherapeutic drug, cisplatin is limited by its toxicity and drug resistance. Therefore, efforts continue for the discovery of novel combination therapies with cisplatin, to increase efficacy and reduce its toxicity. Here, we screened 16 medicinal plant extracts from Northeast part of India and found that leaf extract of Zanthoxylumarmatum DC. (ZALE) induced cytotoxicity as well as an effect on the increasing of the efficiency of chemotherapeutic drugs (cisplatin, mitomycin C and camptothecin). This work shows detail molecular mechanism of anti-cancer activity of ZALE and its potential for combined treatment regimens to enhance the apoptotic response of chemotherapeutic drugs.

Results

ZALE induced cytotoxicity, nuclear blebbing and DNA fragmentation in HeLA cells suggesting apoptosis induction in human cervical cell line. However, the apoptosis induced was independent of caspase 3 activation and poly ADP ribose polymerase (PARP) cleavage. Further, ZALE activated Mitogen-activated protein kinases (MAPK) pathway as revealed by increased phosphorylation of extracellular-signal-regulated kinases (ERK), p38 and c-Jun N-terminal kinase (JNK). Inhibition of ERK activation but not p38 or JNK completely blocked the ZALE induced apoptosis suggesting an ERK dependent apoptosis. Moreover, ZALE generated DNA double strand breaks as suggested by the induction γH2AX foci formation. Interestingly, pretreatment of certain cancer cell lines with ZALE, sensitized the cancer cells to cisplatin and other chemotherapeutic drugs. Enhanced caspase activation was observed in the synergistic interaction among chemotherapeutic drugs and ZALE.

Conclusion

Purification and identification of the bio-active molecules from the ZALE or as a complementary treatment for a sequential treatment of ZALE with chemotherapeutic drugs might be a new challenger to open a new therapeutic window for the novel anti-cancer treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s40659-015-0037-4) contains supplementary material, which is available to authorized users.  相似文献   

13.
Posidonia oceanica (L.) Delile is an endemic Mediterranean sea-grass distributed in the infralittoral zones, where it forms meadows playing a recognized ecological role in the coastal marine habitat. Although its use as a traditional herbal remedy is poorly documented, recent literature reports interesting pharmacological activities as antidiabetic, antioxidant and vasoprotective. Differently from previous literature, this study presents a hydrophilic extraction method that recovers metabolites that may be tested in biological buffers. We showed for the first time in the highly invasive HT1080 human fibrosarcoma cell line that our hydrophilic extract from P. oceanica was able to strongly decrease gene and protein expression of gelatinases MMP-2 and MMP-9 and to directly inhibit in a dose-dependent manner gelatinolytic activity in vitro. Moreover, we have revealed that our extract strongly inhibited HT1080 cell migration and invasion. Biochemical analysis of the hydrophilic extract showed that catechins were the major constituents with minor contribution of gallic acid, ferulic acid and chlorogenic plus a fraction of uncharacterized phenols. However, if each individual compound was tested independently, none by itself was able to induce a direct inhibition of gelatinases as strong as that observed in total extract, opening up new routes to the identification of novel compounds. These results indicate that our hydrophilic extract from P. oceanica might be a source of new pharmacological natural products for treatment or prevention of several diseases related to an altered MMP-2 and MMP-9 expression.  相似文献   

14.
We characterized ouabain-insensitive Na+-ATPase activity present in the plasma membrane of Leishmania amazonensis and investigated its possible role in the growth of the parasite. An increase in Na+ concentration in the presence of 1mM ouabain, increased the ATPase activity with a V(max) of 154.1+/-13.5nmol Pi x h(-1) x mg(-1) and a K0.5 of 28.9+/-7.7mM. Furosemide and sodium orthovanadate inhibited the Na+-stimulated ATPase activity with an IC(50) of 270microM and 0.10microM, respectively. Furosemide inhibited the growth of L. amazonensis after 48h incubation, with maximal effect after 96h. The IC50 for furosemide was 840. On the other hand, ouabain (1mM) did not change the growth of the parasite. Taken together, these results show that L. amazonensis expresses a P-type, ouabain-insensitive Na+-ATPase that could be involved with the growth of the parasite.  相似文献   

15.
An efficient hairy root induction system for an important endangered medicinal plant, Dracocephalum kotschyi, was developed through Agrobacterium rhizogenes-mediated transformation by modifying the co-cultivation medium using five bacterial strains, A4, ATCC15834, LBA9402, MSU440, and A13 (MAFF-02-10266). A drastic increase in transformation frequency was observed when a Murashige and Skoog medium lacking NH4NO3 KH2PO4, KNO3 and CaCl2 was used, resulting in hairy root induction frequencies of 52.3 %, 69.6 %, 48.6 %, 89.0 %, and 80.0 % by A4, A13, LBA9402, MSU440, and ATCC15834 strains, respectively. For shoot induction, hairy roots and unorganized tumors induced by strain ATCC15834 were placed on an MS media supplemented with 0.1, 0.25, 0.5, and 1 mg/l BA plus 0.1 mg/l NAA. The high frequency of shoot regeneration and number of shoot were obtained in the medium containing 0.25 mg/l BA and 0.1 mg/l NAA. Root induction occurred from the base of regenerated shoots on the MS medium supplemented with 0.5 mg/l IBA after 10 days.  相似文献   

16.
An indigenous Bacillus thuringiensis strain B.t.LDC-391 producing cytocidal proteins against human colon cancer cell line, HCT-116, was subjected to phenotypic and genotypic characterization to evaluate its relatedness to B.anthracis. The morphological features of this strain were meta-analyzed with data of other parasporin and insecticidal protein producing Bacillus thuringiensis strains. The conventional biochemical analysis and antibiotic sensitivity test proved it as an ampicillin resistant which is a salient feature, absent in B.anthracis Ames. PCR analysis showed the absence of cyt and parasporin related genes in the genome of B.t.LDC-391. But the strain was positive for cap gene. The sequencing and bio-informatic analysis of cap gene and 16S rDNA of B.t.LDC-391 placed it closer to B.thuringiensis and revealed significant divergence from that of any B.anthracis strain. However our strain lacked β- hemolysis on human erythrocytes which is a common feature of B.anthracis strains and parasporin producers.  相似文献   

17.
A total of seventy-five symbiotic bacterial strains isolated from root nodules of wild Sophora alopecuroides grown in different regions of China's Loess Plateau were characterized. Based on the combined RFLP patterns, thirty-five genotypes were defined among the rhizobia and they were classified into nine genomic species, including Mesorhizobium alhagi and M. gobiense as the main groups, as well as Agrobacterium tumefaciens, M. amorphae, Phyllobacterium trifolii, Rhizobium giardinii, R. indigoferae, Sinorhizobium fredii and S. meliloti as the minor groups according to the 16S rRNA and recA gene analyses. Five and three lineages of nodA and nifH were found, respectively, in these strains, implying that the symbiotic genes of the S. alopecuroides rhizobia had different origins or had divergently evolved. Results of correspondence analysis showed that there was a correlation between rhizobial genotypes and the geographic origins. Possible lateral transfer of the recA and 16S rRNA genes between the P. trifolii and A. tumefaciens strains, and that of symbiotic genes (nodA, nifH) between different genera, was shown by discrepancies of the phylogenetic relationships of the four gene loci. These results revealed diverse rhizobia associated with wild S. alopecuroides grown in different regions of China's Loess Plateau, and demonstrated for the first time the existence of symbiotic A. tumefaciens strains in root nodules of S. alopecuroides.  相似文献   

18.
The bio-efficacy of Aloe vera leaf extract and bacterial insecticide, Bacillus sphaericus larvicidal activity was assessed against the first to fourth instars larvae of Aedes aegypti, under the laboratory conditions. The plant material was shade dried at room temperature and powdered coarsely. A. vera and B. sphaericus show varied degrees of larvicidal activity against various instars larvae of A. aegypti. The LC50 of A. vera against the first to fourth instars larvae were 162.74, 201.43, 253.30 and 300.05 ppm and the LC90 442.98, 518.86, 563.18 and 612.96 ppm, respectively. B. sphaericus against the first to fourth instars larvae the LC50 values were 68.21, 79.13, 93.48, and 107.05 ppm and the LC90 values 149.15, 164.67, 183.84, and 201.09 ppm, respectively. However, the combined treatment of A. vera + B. sphaericus (1:2) material shows highest larvicidal activity of the LC50 values 54.80, 63.11, 74.66 and 95.10 ppm; The LC90 values of 145.29, 160.14, 179.74 and 209.98 ppm, against A. aegypti in all the tested concentrations than the individuals and clearly established that there is a substantial amount of synergist act. The present investigation clearly exhibits that both A. vera and B. sphaericus materials could serve as a potential larvicidal agent. Since, A. aegypti is a container breeder vector mosquito this user and eco-friendly and low-cost vector control strategy could be a viable solution to the existing dengue disease burden. Therefore, this study provides first report on the mosquito larvicidal activity the combined effect of A. vera leaf extract and B. sphaericus against as target species of A. aegypti.  相似文献   

19.
Phosphatidylinositol (4,5) bisphosphate, [PtdIns(4,5)P2], is a signaling lipid involved in many important processes in animal cells such as cytoskeleton organization, intracellular vesicular trafficking, secretion, cell motility, regulation of ion channels, and nuclear signaling pathways. In the last years PtdIns(4,5)P2 and its synthesizing enzyme, phosphatidylinositol phosphate kinase (PIPK), has been intensively studied in plant cells, revealing a key role in the control of polar tip growth. Analysis of the PIPK members from Arabidopsis thaliana, Oryza sativa and Physcomitrella patens showed that they share some regulatory features with animal PIPKs but also exert plant-specific modes of regulation. This review aims at giving an overview on the PIPK family from Arabidopsis thaliana and Physcomitrella patens. Even though their basic structure, modes of activation and physiological role is evolutionary conserved, modules responsible for plasma membrane localization are distinct for different PIPKs, depending on differences in physiological and/or developmental status of cells, such as polarized and non-polarized.  相似文献   

20.

Background and Aims

Manipulation of plant structure can strongly affect light distribution in the canopy and photosynthesis. The aim of this paper is to find a plant ideotype for optimization of light absorption and canopy photosynthesis. Using a static functional structural plant model (FSPM), a range of different plant architectural characteristics was tested for two different seasons in order to find the optimal architecture with respect to light absorption and photosynthesis.

Methods

Simulations were performed with an FSPM of a greenhouse-grown tomato crop. Sensitivity analyses were carried out for leaf elevation angle, leaf phyllotaxis, leaflet angle, leaf shape, leaflet arrangement and internode length. From the results of this analysis two possible ideotypes were proposed. Four different vertical light distributions were also tested, while light absorption cumulated over the whole canopy was kept the same.

Key Results

Photosynthesis was augmented by 6 % in winter and reduced by 7 % in summer, when light absorption in the top part of the canopy was increased by 25 %, while not changing light absorption of the canopy as a whole. The measured plant structure was already optimal with respect to leaf elevation angle, leaflet angle and leaflet arrangement for both light absorption and photosynthesis while phyllotaxis had no effect. Increasing the length : width ratio of leaves by 1·5 or increasing internode length from 7 cm to 12 cm led to an increase of 6–10 % for light absorption and photosynthesis.

Conclusions

At high light intensities (summer) deeper penetration of light in the canopy improves crop photosynthesis, but not at low light intensities (winter). In particular, internode length and leaf shape affect the vertical distribution of light in the canopy. A new plant ideotype with more spacious canopy architecture due to long internodes and long and narrow leaves led to an increase in crop photosynthesis of up to 10 %.  相似文献   

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