共查询到20条相似文献,搜索用时 31 毫秒
1.
Senger MR Seibt KJ Ghisleni GC Dias RD Bogo MR Bonan CD 《Cell biology and toxicology》2011,27(3):199-205
Aluminum is a metal that is known to impact fish species. The zebrafish has been used as an attractive model for toxicology
and behavioral studies, being considered a model to study environmental exposures and human pathologies. In the present study,
we have investigated the effect of aluminum exposure on brain acetylcholinesterase activity and behavioral parameters in zebrafish.
In vivo exposure of zebrafish to 50 μg/L AlCl3 for 96 h at pH 5.8 significantly increased (36%) acetylthiocholine hydrolysis in zebrafish brain. There were no changes in
acetylcholinesterase (AChE) activity when fish were exposed to the same concentration of AlCl3 at pH 6.8. In vitro concentrations of AlCl3 varying from 50 to 250 μM increased AChE activity (28% to 33%, respectively). Moreover, we observed that animals exposed
to AlCl3 at pH 5.8 presented a significant decrease in locomotor activity, as evaluated by the number of line crossings (25%), distance
traveled (14.1%), and maximum speed (24%) besides an increase in the absolute turn angle (12.7%). These results indicate that
sublethal levels of aluminum might modify behavioral parameters and acetylcholinesterase activity in zebrafish brain. 相似文献
2.
Kristin Andersland Guro F. Jølle Olav Sand Trude M. Haug 《The Journal of membrane biology》2010,235(2):121-129
Certain antimicrobial peptides from multicellular animals kill a variety of tumor cells at concentrations not affecting normal
eukaryotic cells. Recently, it was reported that also plantaricin A (PlnA), which is a peptide pheromone with strain-specific
antibacterial activity produced by Lactobacillus plantarum, permeabilizes cancerous rat pituitary cells (GH4 cells), whereas normal rat anterior pituitary cells are resistant to the peptide. To examine whether the preferential permeabilization
of cancerous cells is a general feature of PlnA, we studied its effect on primary cultures of cells from rat liver (hepatocytes,
endothelial, and Kupffer cells) and rat kidney cortex, as well as two epithelial cell lines of primate kidney origin (Vero
cells from green monkey and human Caki-2 cells). The Vero cell line is derived from normal cells, whereas the Caki-2 cell
line is derived from a cancerous tumor. The membrane effects were studied by patch clamp recordings and microfluorometric
(fura-2) monitoring of the cytosolic concentrations of Ca2+ ([Ca2+]i) and fluorophore. In all the tested cell types except Kupffer cells, exposure to 10–100 μM PlnA induced a nearly instant
permeabilization of the membrane, indicated by the following criteria: increased membrane conductance, membrane depolarization,
increased [Ca2+]i, and diffusional loss of fluorophore from the cytosol. At a concentration of 5 μM, PlnA had no effect on any of the cell
types. The Kupffer cells were permeabilized by 500 μM PlnA. We conclude that the permeabilizing effect of PlnA is not restricted
to cancerous cells. 相似文献
3.
4.
Jacqueline Capataz-Tafur Gabriela Trejo-Tapia Mario Rodríguez-Monroy Gabriela Sepúlveda-Jiménez 《Plant Cell, Tissue and Organ Culture》2011,106(1):169-177
Arabinogalactan proteins (AGPs) are glycoproteins present at cell surfaces. Although exact functions of AGPs remain elusive,
they are implicated in plant growth and development. The aim of this study was to evaluate the role of AGPs in the process
of cell aggregation of Beta vulgaris L. suspension cultures. It was observed that B. vulgaris suspension cultures accumulated AGPs in parallel form to its cell growth. The AGPs maximum content in the stationary phase
was 0.330 mg g−1 dry weight (DW) in the cell wall (CW) and 1.534 mg g−1 DW in the culture medium (CM), generating cell aggregates >500 μm (93.21% DW). The addition of tunicamycin (TM) caused a
reduction of AGPs content in CW and CM of 46 and 64%, respectively. These changes were associated with inhibition of growth
and the reduction of the cell aggregates >500 μm (50.0% DW). When TM was removed from the CM, cell growth, aggregation, and
AGPs content on CW and CM were recovered. Precipitation of AGPs with Yariv reagent generated a reduction of 61.14% of AGPs
content in CW and a total inhibition of AGPs secretion in CM. This Yariv treatment generated a reduction in the cell aggregates
>500 μm of 51.31% of DW. When the Yariv reagent was removed from the culture, cells did not recover their AGPs accumulation.
In addition, cell cultures did not recover their ability to grow and aggregate. These results indicate that AGPs are molecules
required in the cellular aggregation process of B. vulgaris L. suspension cultures. 相似文献
5.
The increasing applications of silicon dioxide (SiO2) nanomaterials have been widely concerned over their biological effects and potential hazard to human health. In this study,
we explored the effects of SiO2 nanoparticles (15, 30, and 100 nm) and their micro-sized counterpart on cultured human epidermal Keratinocyte (HaCaT) cells.
Cell viability, cell morphology, reactive oxygen species (ROS), DNA damage (8-OHdG, γH2AX and comet assay) and apoptosis were
assessed under control and SiO2 nanoparticles exposed conditions. As observed in the Cell Counting Kit-8 (CCK-8) assay, exposure to 15, 30 or 100 nm SiO2 nanoparticles at dosage levels between 0 and 100 μg/ml decreased cell viability in a concentration- and size dependent manner
and the IC50 of 24 hour exposure was 19.4 ± 1.3, 27.7 ± 1.5 and 35.9 ± 1.6 μg/ml for 15, 30 and 100 nm SiO2 nanoparticles, respectively. Morphological examination revealed cell shrinkage and cell wall missing after SiO2 nanoparticle exposure. Increase in intracellular ROS level and DNA damage as well as apoptosis were also observed in SiO2 nanoparticle-exposed HaCaT cells. Exposure to SiO2 nanoparticles results in a concentration- and size-dependent cytotoxicity and DNA damage in cultural HaCaT cells which is
closely correlated to increased oxidative stress. 相似文献
6.
Ling Li Jun Qin Qiang Feng Hao Tang Rong Liu Liqing Xu Zhinan Chen 《Molecular biotechnology》2011,47(1):9-17
While heparin has been shown to eliminate cell aggregation in suspension adaptations of insect and HEK293 cells for virus-based
cell cultures, the role of heparin in long period serum-free suspension adaptation of the anchorage-dependent Chinese hamster
ovary (CHO) cell lines remains inconclusive. In this paper, we explore the potential application of heparin in suspension
adaptation of CHO cell line which produces an anti-human chimeric antibody cHAb18. Heparin showed a concentration-dependent
inhibition of CHO–TS28 cell-to-cell adhesion, with a significant inhibitory effect occurring when the concentration exceeded
250 μg/ml (P < 0.001). Heparin also exhibited a cell aggregation elimination role at all concentrations (P < 0.001). Furthermore, heparin promoted cell growth and antibody secretion, with the highest cell density ((99.83 ± 12.21) × 104 cells/ml, P = 0.034) and maximum antibody yield ((9.46 ± 0.94) mg/l, P < 0.001) both occurring at 250 μg/ml heparin. When agitated, cell aggregates were effectively dispersed by 250 μg/ml heparin
and a single-cell suspension culture process was promoted. In suspension adapted CHO–TS28 cells, cell growth rates and specific
antibody productivity were maintained; while antigen-binding activity improved slightly. Together, our results show that heparin
may promote suspension adaptation of anchorage-depended CHO cells by resisting cell aggregation without reducing cell growth,
antibody secretion, and antigen-binding activity. 相似文献
7.
I S Komolov A A Bulatov Iu K Trunin S Iu Serpukhovitin E I Marova I I Dedov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(4):421-424
This paper describes the development of method of preparing cell suspension obtained from surgical material of patients with pituitary adenomas and acromegaly as well as the procedure of subsequent long-term cultivation in monolayers of the cells isolated. As judged by visual inspection and measurement of growth hormone and prolactin secretion, tumor pituitary cells kept viability and functional activity for at least 6 days of growing in vitro. Immunocytochemical visualization of somato- and lactotrophs of the same histological preparations permitted us to show that vast majority of cultured cells is represented by somatotrophs; however, a small portion of cell population is represented by lactotrophs and lactosomatotrophs. The peculiarities of cytoarchitectonics in two types of cell cultures of human somatotropinomas were studied. 相似文献
8.
Simões-Gurgel Claudia Cordeiro Lívia da Silva de Castro Tatiana Carvalho Callado Cátia Henriques Albarello Norma Mansur Elisabeth 《Plant Cell, Tissue and Organ Culture》2011,106(3):537-545
The effects of different levels of Murashige and Skoog (MS) basal medium, 2,4-dichlorophenoxyacetic acid (2,4-D), and sucrose
on anthocyanin production and biomass accumulation of cell suspension cultures of Cleome rosea were investigated. Cultures were established in liquid MS medium containing 30 g l−1 sucrose and supplemented with 0.90 μM 2,4-D. Proliferating cell suspension cultures achieved the highest growth capacity,
a fourfold increase in biomass accumulation, following subculture at the exponential growth phase, 14–18 days of culture.
Moreover, the presence of 2,4-D was essential for anthocyanin production and biomass accumulation. On the other hand, increasing
levels of sucrose above 30 g l−1 resulted in a drastic reduction in biomass accumulation. Anthocyanin production was highest in cell suspension cultures grown
on half-strength MS medium (1/2 MS), 30 g l−1 sucrose, and 0.45 μM 2,4-D. These cell suspension cultures were mainly composed of small aggregates of spherical cells with
similar morphology observed in anthocyanin-producing and non-producing cultures. Moreover, microscopic analysis of anthocyanin-producing
cultures showed the presence of mixtures of non-pigmented, low-pigmented, and high-pigmented cells. 相似文献
9.
Wei XJ Wu J Ni YD Lu LZ Zhao RQ 《In vitro cellular & developmental biology. Animal》2011,47(10):735-741
Previous studies have shown that the in ovo injection of equol can markedly improve the water-holding capacity of muscles
of broilers chickens at 7 wk of age through promotion of the antioxidant status. We aimed to investigate directly the antioxidant
effects of equol on muscle cells in broilers. Muscle cells were separated from leg muscle of embryos on the 11th day of incubation
and treated with equol and H2O2, either alone or together. Cells were pretreated with medium containing 1, 10, or 100 μM equol for 1 h prior to the addition
of 1 mM H2O2 for a further 1 h. Photomicrographs of cells were obtained. Cell viability, malondialdehyde (MDA) content, and L-lactate
dehydrogenase (LDH) activity in the cell supernatant, as well as intracellular total superoxide dismutase (T-SOD) and glutathione
peroxidase (GSH-Px) activities were determined. Treatment with 1 mM H2O2 caused serious damage to cells, indicated by comets with no clear head region but a very apparent tail of DNA fragments.
Pretreatment with low (1 μM) but not high concentrations of equol (10 μM) inhibited cell damage, while 100 μM equol caused
more serious damage than H2O2 alone. Pretreatment with 1 μM equol had no effect on cell viability, while pretreatment with 10 and 100 μM equol significantly
decreased cell viability in a dose-dependent manner. Compared with H2O2 alone, pretreatment with low-dosage equol markedly decreased LDH activity and MDA production in the supernatant, significantly
increased intracellular T-SOD activity (P < 0.05) and tended to increase intracellular GSH-Px activity (0.05 < P < 0.1). Pretreatment with high-dosage equol (10 and 100 μM) significantly enhanced LDH activity, but had no effect on MDA
content, T-SOD or GSH-Px activity induced by H2O2, except for an obvious increase in GSH-Px activity caused by 10 μM equol. These results indicate that equol at low dosage
can prevent skeletal muscle cell damage induced by H2O2, while pretreatment with high-dosage equol shows a synergistic effect with H2O2 in inducing cell damage. 相似文献
10.
Chow-Chin Tong Yew-Keong Choong Nor-Aini-B Umar Mohamed-Mustapha Noordin Suhaila Mohamed 《World journal of microbiology & biotechnology》2009,25(4):687-695
Ganoderma lucidum powder using hot water and methanol extraction methods indicated a twofold more active cytotoxic activity with IC50 of 44 ± 3.8 μg/ml in the latter method. The representative dose-response curves of the G. lucidum crude extracts on J558 cell-lines revealed that there were great similarities between the curves which reflected rapid killing
activities. The percentage viability of the J558 cell exposed to these crude extracts was dose dependent only up to 150 μg/ml.
After which, there was no significant reduction when the dose was increased to 200 or 400 μg/ml. The morphological alterations
induced by the crude extract were examined under the phase contrast, fluorescent and electron microscopy. When J558 cells
were treated with doses higher than 50 μg/ml of the crude extract, obvious morphological changes and apoptosis occurred after
72 h. At 400 μg/ml, most of the cells showed necrosis characterized as small fragments with uniformly stained red nuclei.
The apoptotic and necrotic cells increased by 16.5 and 29.1%, respectively whereas the viable cells decreased by as much as
45.6. The mode of cell death via apoptosis was 3.6% higher than necrosis. However, these morphological changes were not observed
in the case of 3T3 cells. Results obtained from scanning electron microscopy and transmission electron microscopy further
confirmed the occurrence of various apoptotic and necrotic features. 相似文献
11.
Shoots and roots ofBacopa monniera (L.) Wettst. have been regenerated from nodal segments on MS medium containing combinations of NAA and BAP. The cultures
showed 100% regeneration on MS (sucrose 2%) medium added with NAA (0.2 mg L-1), BAP (0.5 mg L-1) and glutamine (50 mg L-1). Supplemented with aluminium chloride (up to 400 μM), this medium could ensure successful survival of regenerants. AH the
regenerants, maintained on AlCl3-supplemented medium for the last three years, failed to grow when transferred to AlCl3-free media. Aluminium stress also induced synthesis of proline and proteins. The rate of photosynthesis decreased at increased
aluminium concentrations. 相似文献
12.
Selvatici R Previati M Marino S Marani L Falzarano S Lanzoni I Siniscalchi A 《Neurochemical research》2009,34(5):909-916
The features of neuronal damage induced by the mitochondrial toxin NaN3 were investigated in rat primary cortical neuron cultures. Cell viability (MTT colorimetric determination) and transmembrane
mitochondrial potential (J-C1 fluorescence) were concentration-dependently reduced 24 h after NaN3; neither nuclear fragmentation by DAPI, nor Annexin V positivity by flow cytometry were detected, ruling out the occurrence
of apoptosis. The loss in cell viability (to 54 ± 2%) observed 24 h after a 10-min treatment with 3 mM NaN3 was prevented by the NMDA glutamate receptor antagonist MK801 (1 μM), by the antioxidants trolox (100 μM) and acetyl-l-carnitine (1 mM) and by the nitric oxide synthase inhibitor, L-NAME (100 μM), but not by the guanylylcyclase inhibitor ODQ,
10 μM. The mitochondrial dysfunction induced by NaN3 provides a common platform for investigating the mechanisms of both ischemic and degenerative neuronal injury, useful for
screening potential protective agents against neuronal death.
Rita Selvatici and Maurizio Previati equally contributed to the work. 相似文献
13.
Oxidative stress can be a significant cause of cell death and apoptosis. We performed studies in HepG2 cells to explore whether
prior exposure to oxidative stress (“oxidative preconditioning”) and geldanamycin (GA) treatment can protect the cell from
damage caused by subsequent oxidative insults. The cells were treated with 10 nM GA for 24 h before oxidative stress. Oxidative
preconditioning was achieved by 2 h exposures to H2O2 (50 μM) separated by a 10-h recovery period in normal culture medium. Oxidative stress was induced by exposure to 500 μM
H2O2 for 24 h. The effects of GA and oxidative preconditioning were investigated on the formation of Hsp90, vimentin, insoluble
vimentin aggregates, and cleavage of vimentin in a cell culture model of oxidative stress. GA treatment leads to enhanced
expression of Hsp90 and vimentin and to inhibition of vimentin protein aggregation. Similar results were obtained by oxidative
preconditioning. It is confirmed that low concentrations of GA protected HepG2 cells from subsequent oxidative stress by increasing
the levels of Hsp90 and by alleviating the extent of cell apoptosis induced by oxidative stress, which is similar to oxidative
preconditioning. However, in contrast to preconditioning, GA treatment obviously changed binding activity of Hsp90 to vimentin
cleavages. All the above indicated that low concentrations of GA treatment triggered cell protection from oxidative stress.
Both the level of Hsp90 and its ability to bind with vimentin were changed by low concentrations of GA and might contribute
to oxidative stress protection. 相似文献
14.
In vitro release behavior and cytotoxicity of doxorubicin-loaded gold nanoparticles in cancerous cells 总被引:1,自引:0,他引:1
Doxorubicin (DOX), a common cancer chemotherapeutics, was conjugated to folate-modified thiolated-polyethylene glycol-functionalized
gold nanoparticles. The in vitro, controlled release behavior of DOX-loaded gold nanoparticles was observed using porous dialysis
membranes (cut-off = 2 kDa). DOX-loaded gold nanoparticles had higher cytotoxicity for folate-receptor-positive cells (KB
cells) compared to folate-receptor-negative cells (A549 cells) which were 48 and 62% viable for 10 μM doxorubicin, respectively.
This indicates the potential of these nano-carriers for targeted-delivery. In addition, healthy cell viability was 69% for
10 μM free doxorubicin whereas for the same content of drug in DOX-loaded nanoparticles healthy cell viability increased to
80%. 相似文献
15.
El Bahri Trabelsi Selima Naija Nedra Elloumi Zina Belfeleh Monji Msellem Rachida Ghezel Sadok Bouzid 《Acta Physiologiae Plantarum》2011,33(2):319-324
Somatic embryogenesis of olive Olea europaea (L.) ‘Chetoui’ was studied using cell suspension cultures initiated from mature leaf-derived calli. Calli were developed
on half-strength MS medium supplemented with 10 μM NAA and 2.25 μM 2i-P in the dark. Different combinations of three plant
growth regulators (2,4-D, NAA and zeatin) were tested to determine cell proliferation and somatic embryogenesis induction
and differentiation. Embryogenic suspension cultures were established in olive-modified medium for embryogenesis (OMe) containing
2.5 μM 2,4-D and 2.5 μM zeatin. Pre-globular and globular embryos were induced from mature olive tissue in liquid medium.
In addition, the nitrogen form as inorganic (reduced; (NH4)2SO4 or oxidized; KNO3) and organic (CH) was used separately or in combination to improve the cell growth and proliferation. The most effective
growth rate and cell proliferation were obtained with the medium containing inorganic and organic nitrogen forms. 相似文献
16.
Jacqueline A. Jordan Ashley M. Verhoff Julie E. Morgan David G. Fischer 《In vitro cellular & developmental biology. Animal》2009,45(10):602-613
Prior chemical and physical analysis of lunar soil suggests a composition of dust particles that may contribute to the development
of acute and chronic respiratory disorders. In this study, fine Al2O3 (0.7 μm) and fine SiO2 (mean 1.6 μm) were used to assess the cellular uptake and cellular toxicity of lunar dust particle analogs. Respiratory cells,
murine alveolar macrophages (RAW 264.7) and human type II epithelial (A549), were cultured as the in vitro model system. The
phagocytic activity of both cell types using ultrafine (0.1 μm) and fine (0.5 μm) fluorescent polystyrene beads was determined.
Following a 6-h exposure, RAW 264.7 cells had extended pseudopods with beads localized in the cytoplasmic region of cells.
After 24 h, the macrophage cells were rounded and clumped and lacked pseudopods, which suggest impairment of phagocytosis.
A549 cells did not contain beads, and after 24 h, the majority of the beads appeared to primarily coat the surface of the
cells. Next, we investigated the cellular response to fine SiO2 and Al2O3 (up to 5 mg/ml). RAW 264.7 cells exposed to 1.0 mg/ml of fine SiO2 for 6 h demonstrated pseudopods, cellular damage, apoptosis, and necrosis. A549 cells showed slight toxicity when exposed
to fine SiO2 for the same time and dose. A549 cells had particles clustered on the surface of the cells. Only a higher dose (5.0 mg/ml)
of fine SiO2 resulted in a significant cytotoxicity to A549 cells. Most importantly, both cell types showed minimal cytotoxicity following
exposure to fine Al2O3. Overall, this study suggests differential cellular toxicity associated with exposure to fine mineral dust particles. 相似文献
17.
Bestwick CS Ralton LD Milne L Kong Thoo Lin P Duthie SJ 《Cell biology and toxicology》2011,27(6):455-463
Bisnaphthalimido compounds bis-intercalate to DNA via the major groove and are potentially potent cancer therapeutics. Previously,
we incorporated natural polyamines as linkers connecting the two naphthalimido ring moieties to create a series of soluble
bisnaphthalimidopropyl polyamines (BNIPPs). Here, extending earlier work on bisnaphthalimidopropylspermidine (BNIPSpd)-induced
apoptosis in colon adenocarcinoma Caco-2 cells, we compare the cytotoxicity and genotoxicity of BNIPSpd relative to the spermine
and oxaspermine derivatives, bisnaphthalimidopropylspermine (BNIPSpm) and bisnaphthalimidopropyloxaspermine (BNIPOSpm). The
order of cytotoxicity after 24 h was BNIPSpd (IC50 = 0.47 μM) > BNIPSpm (IC50 = 10.04 μM) > BNIPOSpm (IC50 >50 μM). After a 72-h BNIPOSpm exposure, an IC50 = 10.25 μM was achieved. With 4-h exposure to BNIPSpd or BNIPSpm or 12-h exposure to BNIPOSpm, concentrations ≥1 μM induced
a significant dose-dependent increase in DNA damage as measured by alkaline single-cell gel electrophoresis. The longer incubation
times required for BNIPOSpm to induce DNA strand breaks reflect a slower rate of BNIPOSpm cellular distribution as monitored
via BNIPP fluorescence within the cells. Moreover, exposure to a non-genotoxic concentration of BNIPSpd, BNIPSpm (0.1 μM for
4 h) or BNIPOSpm (0.1 μM for 12 h) induced a significant decrease in repair of oxidative DNA damage induced by hydrogen peroxide.
In conclusion, BNIPP exposure in Caco-2 cells is associated with significant induction of DNA damage and inhibition of DNA
repair at non-genotoxic concentrations. The latter is a novel consequence of BNIPP–cell interactions which adds to the spectrum
of therapeutically relevant activities that may be exploited for the design and development of naphthalimide-based therapeutics. 相似文献
18.
Anti-proliferative and apoptotic effects of oleuropein and hydroxytyrosol on human breast cancer MCF-7 cells 总被引:1,自引:0,他引:1
Olive oil intake has been shown to induce significant levels of apoptosis in various cancer cells. These anti-cancer properties
are thought to be mediated by phenolic compounds present in olive. These beneficial health effects of olive have been attributed,
at least in part, to the presence of oleuropein and hydroxytyrosol. In this study, oleuropein and hydroxytyrosol, major phenolic
compound of olive oil, was studied for its effects on growth in MCF-7 human breast cancer cells using assays for proliferation
(MTT assay), cell viability (Guava ViaCount assay), cell apoptosis, cellcycle (flow cytometry). Oleuropein or hydroxytyrosol
decreased cell viability, inhibited cell proliferation, and induced cell apoptosis in MCF-7 cells. Result of MTT assay showed
that 200 μg/mL of oleuropein or 50 μg/mL of hydroxytyrosol remarkably reduced cell viability of MCF-7 cells. Oleuropein or
hydroxytyrosol decrease of the number of MCF-7 cells by inhibiting the rate of cell proliferation and inducing cell apoptosis.
Also hydroxytyrosol and oleuropein exhibited statistically significant block of G1 to S phase transition manifested by the increase of cell number in G0/G1 phase. 相似文献
19.
Chtourou Y Trabelsi K Fetoui H Mkannez G Kallel H Zeghal N 《Neurochemical research》2011,36(8):1546-1557
Manganese (Mn) is an essential trace element required for ubiquitous enzymatic reactions. Chronic overexposure to this metal
may promote potent neurotoxic effects. The mechanism of Mn toxicity is not well established, but several studies indicate
that oxidative stress play major roles in the Mn-induced neurodegenerative processes. Silymarin (SIL) has antioxidant properties
and stabilizes intracellular antioxidant defense systems. The aim of this study was to evaluate the toxic effects of MnCl2 on the mouse neuroblastoma cell lines (Neuro-2A), to characterize the toxic mechanism associated with Mn exposure and to
investigate whether SIL could efficiently protect against neurotoxicity induced by Mn. A significant increase in LDH release
activity was observed in Neuro-2A cells associated with a significant decrease in cellular viability upon 24 h exposure to
MnCl2 at concentrations of 200 and 800 μM (P < 0.05) when compared with control unexposed cells. In addition, exposure cells to MnCl2 (200 and 800 μM), increases oxidant biomarkers and alters enzymatic and non enzymatic antioxidant systems. SIL treatment
significantly reduced the levels of LDH, nitric oxide, reactive oxygen species and the oxidants/antioxidants balance in Neuro-2A
cells as compared to Mn-exposed cells. These results suggested that silymarin is a powerful antioxidant through a mechanism
related to its antioxidant activity, able to interfere with radical-mediated cell death. SIL may be useful in diseases known
to be aggravated by reactive oxygen species and in the development of novel treatments for neurodegenerative disorders such
as Alzheimer or Parkinson diseases. 相似文献
20.
Bonfim VL de Carvalho DD Ponce-Soto LA Kassab BH Marangoni S 《Cell biology and toxicology》2009,25(6):523-532
Purified phospholipase A2 (PLA2) enzymes from Bothrops jararacussu snake venom were examined to evaluate NIH 3T3 and COS7 fibroblast cytotoxicity, as well as muscle myotoxic and inflammatory
activities. Separation of fractions Bj-VII (from BthTX-I; a Lys49 PLA2 homolog) and 6-1 and 6-2 (from BthTX-II; an Asp49 PLA2)
from B. jararacussu snake venom by SDS-PAGE in tricine buffer in the absence and presence of dithiothreitol revealed a homodimer with an estimated
molecular mass of ∼30 kDa (monomer mass ∼15 kDa). This finding indicates that these toxins form dimeric complexes—a previously
reported tendency among PLA2s. These toxins were assayed for viability with the MTT assay, which is used to examine the effects
of phospholipases on the mitochondrial viability of cells. The toxins were also assayed for cytolysis of the fibroblast cell
lines NIH 3T3 and COS7 by quantification of lactate dehydrogenase released into the medium. The results indicate that the
PLA2s 6-1, 6-2 and the Bj-VII PLA2 homolog studied here induce moderate footpad edema and local myotoxicity. Moreover, exposure
to these phospholipases led to a reduction in fibroblast viability; at the 1 μM dose of PLA2 tested, a reduction of 50% in
cell viability was observed. The present findings indicate that the inflammatory activity observed in envenomation may be
correlated with the cytotoxicity observed in fibroblasts. 相似文献