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2.
Ying Yong Sheng Tai Xue Bao ; 30(5): 1563-1570, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31107012

RESUMO

Thuja koraiensis, a second-class nationally protected plant species, is a unique endangered tree species in Changbai Mountain, with important economic and ornamental value. In this study, the age structure, static life table, and survival function of T. koraiensis were established by using individual root diameter and age data based on investigation of wild resources in the main distribution areas of T. koraiensis. The population development trend was predicted by dynamic index and time series analysis. The results showed that the age-class structure of T. koraiensis population was in the shape of "∩", which was a decline type. The survival curve of T. koraiensis population under the dark coniferous forest was the Deevey-3 type, and was Deevey-2 type in pure forest community. Population survival analysis showed that the survival function of T. koraiensis appeared irregular fluctuation under the dark coniferous forest. The population distribution showed dynamic features of sharp drop in early age period, stable in middle age period, and decline in old age pe-riod. In the pure forest community, the dynamic pattern was characterized by the stability in early age period, growth in middle age period, and recession in old age period. Dynamic index and time series analysis showed that the decline rate of dark coniferous forest community was slightly higher than that of pure forest community. Our results showed that T. koraiensis had some recovery ability and that artificial tending should be used to promote its normal regeneration.


Assuntos
Ecossistema , Espécies em Perigo de Extinção , Pinus , Thuja/crescimento & desenvolvimento , China , Monitoramento Ambiental , Florestas , Dinâmica Populacional , Árvores
3.
Neural Regen Res ; 13(12): 2147-2155, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30323145

RESUMO

Activated nucleotide binding to the oligonucleotide receptor protein 3 (NLRP3) inflammasome is possibly involved in the pathogenesis of Alzheimer's disease through oxidative stress and neurogenic inflammation. Low expression of the signal transducer and activator of transcription 3 (STAT3) gene may promote the occurrence of neurodegenerative diseases to some extent. To clarify the roles of the NLRP3 inflammasome and STAT3 expression in oxidative stress, (1) SHSY5Y cells were incubated with 1 mM H2O2 to induce oxidative stress injury, and the expression of human-cell-specific signal transduction, STAT3-shRNA silencing signal transduction and STAT3 were detected. Cells were pretreated with Ca2+ chelator BAPATA-AM (0.1 mM) for 30 minutes as a control. (2) Western blot assay was used to analyze the expression of caspase-1, NLRP3, signal transduction and STAT3. Enzyme-linked immunosorbent assay was used to analyze interleukin-1ß levels. Flow cytometry was carried out to calculate the number of apoptotic cells. We found that H2O2 treatment activated NLRP3 inflammasomes and decreased phosphorylation of signal transduction and STAT3 serine 727. BAPTA-AM pretreatment abolished the H2O2-induced activation of NLRP3 inflammasomes, caspase-1 expression, interleukin-1ß expression and apoptosis in SHSY5Y cells, and had no effect in cells with downregulated STAT3 expression by RNAi. The findings suggest that downregulation of signal transduction and STAT3 expression may enhance the oxidative stress mediated by NLRP3, which may not depend on the Ca2+ signaling pathway.

4.
Acta Pharmacol Sin ; 39(1): 97-106, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28770825

RESUMO

Renal ischemia-reperfusion injury (IRI) is regarded as a leading cause of acute kidney failure and renal dysfunction. Previous studies show that kappa opioid receptor (KOR) agonists can attenuate IRI in cardiomycytes and neuronal cells. In this study we explored the effects of a KOR agonist on renal IRI and the underlying mechanisms in vivo and in vitro. An IRI model was established in SD rats, which were intravenously pretreated with a KOR agonist U50448H (1 mg/kg), a KOR antagonist Nor-BNI (2 mg/kg) followed by U50448H (1 mg/kg), or the PI3K inhibitor wortmannin (1.4 mg/kg) followed by U50448H (1 mg/kg). U50448H pretreatment significantly decreased the serum levels of creatinine (Cr) and BUN, the renal tubular injury scores and the apoptotic index (AI) in IRI model rats. Furthermore, U50448H significantly increased SOD activity and NO levels, and reduced the MDA levels in the kidney tissues of IRI model rats. Moreover, U50448H significantly increased the phosphorylation of Akt, eNOS and PI3K in the kidney tissues of IRI model rats. All the beneficial effects of U50448H were blocked by Nor-BNI or wortmannin pre-administered. Similar results were observed in vitro in renal tubular epithelial NRK-52E cells subjected to a hypoxia-reoxygenation (HR) procedure. Our results demonstrate that the KOR agonist U50448H protects against renal IRI via activating the PI3K/Akt signaling pathway.


Assuntos
(trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/uso terapêutico , Rim/efeitos dos fármacos , Receptores Opioides kappa/agonistas , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Rim/patologia , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Superóxido Dismutase
5.
Am J Transl Res ; 9(7): 3499-3513, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804566

RESUMO

We investigated the ability of microRNA-93 (miR-93) to influence proliferation, invasion, migration, and apoptosisofrenal cell carcinoma (RCC) cells via transforming growth factor-ß/solvated metal atom dispersed (TGF-ß/Smad) signaling by targeting runt-related transcription factor 3 (RUNX3). RCC tissues with corresponding adjacent normal tissues were collected from 249 RCC patients. And normal renal tissues were collected from patients without RCC who received nephrectomy. The RCC cell line ACHN was treated with miR-93 mimic, mimic-negative control (NC), miR-93 inhibitor, inhibitor-NC, and miR-93 inhibitor + small interfering RNA (siRNA) against RUNX3 (si-RUNX3). Expression of miR-93, RUNX3, TGF-ß, and Smad4 were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. Cell proliferation was assessed by the Metallothioneins (MTS) assay, cell invasion by the wound-healing assay, cell migration by the Transwell assay, and cell cycle and apoptosis by flow cytometry. Compared with normal renal tissues, the expression of miR-93 and TGF-ß were higher while that of RUNX3 and Smad4 were low in RCC and adjacent normal tissues (all P<0.05). RUNX3 was confirmed as a target of miR-93 by the dual luciferase reporter gene assay. Compared with mimic-NC group, cell proliferation, invasion, migration and cells from G0/G1 to S phase enhanced but the apoptosis decreased in the miR-93 mimic group (all P<0.05). Compared with inhibitor-NC group, proliferation, invasion, and migration reduced, while apoptosis increased, and cells at G0/G1 phase arrested in the miR-93 inhibitor group (all P<0.05). Compared with miR-93 inhibitor group, cell proliferation, invasion, and migration increased with increasing cells from G1 to S phase while the apoptosis decreased, in miR-93 inhibitor + si-RUNX3 group (all P<0.05). In conclusion, miR-93 inhibits apoptosis and promotes proliferation, invasion, and migration of RCC cells via TGF-ß/Smad signaling by inhibiting RUNX3.

6.
Langmuir ; 33(25): 6390-6397, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28594182

RESUMO

Novel composite gel electrolytes were prepared using self-assembled organogels as scaffolds. Mixing silica with the low-molecular-weight poly(ethylene glycol) (PEG)-based electrolytes resulted in precipitation due to significant aggregation of silica. However, clear and transparent PEG-silica composite gel electrolytes were obtained with 1,3:2,4-dibenzylidene-d-sorbitol (DBS) organogels. The organogels resulted from the formation of DBS nanofibrillar networks in which the diameter sizes of the nanofibrils ranged from 10 to 100 nm, as observed by transmission electron microscopy. These three-dimensional nanofibrillar networks entrapped the silica and prevented its aggregation. The thermal properties, such as gel dissolution and thermal degradation temperatures, of the composite gels significantly increased with increasing silica content, as determined by polarizing optical microscopy and thermogravimetric analysis. The conductivity of the prepared composite gel electrolytes was clearly enhanced by increasing the silica content. The silica was well dispersed along the DBS nanofibrillar networks, establishing homogeneous microstructures and effective contact with other components of the electrolytes, leading to an increase in the conductivity.

7.
Fish Shellfish Immunol ; 55: 367-73, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27298271

RESUMO

Natucin C (NC) and Natucin P (NP) are two kinds of antimicrobial peptides (AMPs). In the present study, the effects of NC-NP mixture on a tilapia species (Oreochromis niloticus) were examined. Animals were fed with either a control diet or one of five AMP-supplemented diets for eight weeks. AMP-supplemented diets contained five increasing levels of NP from G1 to G5 and one level of NC (200 mg/kg). Results showed that fish in the G3, G4 and G5 groups had significantly higher levels of total protein (TP), albumin (ALB) and globulin (GLO) in serum than fish in the control group. Fish fed with G4 and G5 diets exhibited significantly higher high-density lipoprotein cholesterol (HDL-C) levels compared to the control fish. Lipopolysaccharide (LPS) levels in all AMP-supplemented groups were significantly lower than the control. In addition, the total antioxidant capacity (TAOC) and lysozyme (LZM) activities were significantly increased in fish fed with the G3 and G4 diets, respectively compared to the control. The serum malondialdehyde (MDA) levels in fish fed with AMP-supplemented diets were significantly decreased compared to those not supplemented with AMPs. Furthermore, the mRNA expressions of tumor necrosis factor alpha (TNF-α), interleukin-1-beta (IL-1ß), gamma interferon (IFN-γ) and heat shock protein 70 (HSP70) in the hepatopancreas, spleen, kidney and gill were measured. Overall, the expression levels were enhanced in an NP dose-dependent and tissue-specific manner. The expressions of four genes in four organs (except IL-1ß in spleen, and TNF-α and HSP70 in gill) were significantly upregulated in fish fed with the G5 diet. Fish fed with the G4 diet had increased expression levels of IL-1ß in spleen and IFN-γ in kidney. The relative expression levels of TNF-α, IL-1ß and HSP70 in the hepatopancreas in fish fed with the G3 diet were significantly upregulated compared to the control. Transcriptional levels of IL-1ß and HSP70 in the hepatopancreas, IFN-γ and HSP70 in the kidney and IL-1ß in the gills of fish fed with the G2 diet were upregulated. Taken together, our results indicated that the NC-NP mixture can enhance the antioxidant capacity and innate immune ability of O. niloticus, indicating that this mixture might be a potential alternative to antibiotics when used as a feed additive.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antioxidantes/metabolismo , Ciclídeos , Imunidade Inata/efeitos dos fármacos , Ração Animal/análise , Animais , Análise Química do Sangue/veterinária , Ciclídeos/sangue , Ciclídeos/imunologia , Dieta/veterinária
9.
Sci Rep ; 5: 13016, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26268675

RESUMO

High-porosity magnesia phosphate paste (HPMPP) was prepared via the pre-foaming method. In the pre-foaming method, sintering treatment was not required. The bulk density and maximum compressive strength of the HPMPP prepared according to the ratio of water to solids (W/So) of 0.32 reached 464.00 ± 5.00 Kg/m(3) and 0.30 ± 0.05 MPa, respectively. The compressive strength increased with the increases in the addition amounts of sodium silicate and polypropylene fibers. The bulk density of HPMPP increased with the increase in the addition of sodium silicate and decreased with the increase in the addition of polypropylene fibers. Besides, the porosity of the magnesia phosphate paste increased from 79.85% to 81.27% and from 80.31% to 83.75% after the addition of sodium silicate and polypropylene fibers respectively. The highest porosity (83.75%) of the prepared HPMPP was realized under the addition proportion (sodium silicate: polypropylene fibers: solids = 0.06:0.0025:1). The average pore size of the prepared HPMPP is about 180 µm and the pore distribution range is relatively narrow. The hydration product (struvite) is combined with MgO particle one by one and then coated on the surface of bubbles. With the decrease of the water content, after breaking bubbles, the porous structure can be achieved.

10.
Cell Biochem Funct ; 33(6): 356-66, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26178702

RESUMO

The study was aimed to investigate the mechanism and administration timing of bone marrow-derived mesenchymal stem cells (BMSCs) in bleomycin (BLM)-induced pulmonary fibrosis mice. Thirty-six mice were divided into six groups: control group (saline), model group (intratracheal administration of BLM), day 1, day 3 and day 6 BMSCs treatment groups and hormone group (hydrocortisone after BLM treatment). BMSCs treatment groups received BMSCs at day 1, 3 or 6 following BLM treatment, respectively. Haematoxylin and eosin and Masson staining were conducted to measure lung injury and fibrosis, respectively. Matrix metalloproteinase (MMP9), tissue inhibitor of metalloproteinase-1 (TIMP-1), γ-interferon (INF-γ) and transforming growth factor ß1 (TGF-ß) were detected in both lung tissue and serum. Histologically, the model group had pronounced lung injury, increased inflammatory cells and collagenous fibres and up-regulated MMP9, TIMP-1, INF-γ and TGF-ß compared with control group. The histological appearance of lung inflammation and fibrosis and elevation of these parameters were inhibited in BMSCs treatment groups, among which, day 3 and day 6 treatment groups had less inflammatory cells and collagenous fibres than day 1 treatment group. BMSCs might suppress lung fibrosis and inflammation through down-regulating MMP9, TIMP-1, INF-γ and TGF-ß. Delayed BMSCs treatment might exhibit a better therapeutic effect. Highlights are as follows: 1. BMSCs repair lung injury induced by BLM. 2. BMSCs attenuate pulmonary fibrosis induced by BLM. 3. BMSCs transplantation down-regulates MMP9 and TIMP-1. 4. BMSCs transplantation down-regulates INF-γ and TGF-ß. 5. Delayed transplantation timing of BMSCs might exhibit a better effect against BLM.


Assuntos
Interferon gama/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fibrose Pulmonar/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Antibióticos Antineoplásicos/metabolismo , Bleomicina , Medula Óssea/metabolismo , Inflamação/metabolismo , Lesão Pulmonar/metabolismo , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamente
12.
World J Gastroenterol ; 17(40): 4479-87, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22110278

RESUMO

AIM: To investigate the expression and localization of paxillin in rat pancreas during development. METHODS: Pancreata from Sprague Dawley rat fetuses, embryos, young animals, and adult animals were used in this study. Expression levels of paxillin in pancreata of different development stages were detected by reverse transcription polymerase chain reaction and Western blotting. To identify the cell location of paxillin in the developing rat pancreas, immunohistochemistry and double-immunofluorescent staining were performed using antibodies for specific cell markers and paxillin, respectively. RESULTS: The highest paxillin mRNA level was detected at E15.5 (embryo day 15.5) following a decrease in the later developmental periods (P < 0.05 vs E18.5, P0 and adult, respectively), and a progressively increased paxillin protein expression through the transition from E15.5 to adult was detected. The paxillin positive staining was mainly localized in rat islets of Langerhans at each stage tested during pancreas development. CONCLUSION: The dynamic expression of paxillin in rat pancreas from different stages indicates that paxillin might be involved in some aspects of pancreatic development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Pâncreas/embriologia , Pâncreas/crescimento & desenvolvimento , Pâncreas/metabolismo , Paxilina/metabolismo , Animais , Feminino , Masculino , Análise em Microsséries , Organogênese/fisiologia , Paxilina/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 32(2): 120-4, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21518617

RESUMO

OBJECTIVE: To evaluate the safety and immunogenicity of split influenza vaccine (Anflu(®)). METHODS: An open-labeled clinical trial was carried out in adults aged 18 - 60 years and elders aged over 60 years from August to September, 2010 in Shenyang, Liaoning province. One dose of split influenza vaccine was administered and adverse events were observed. Serum samples were obtained prior to vaccination and 21 days post vaccination. A/H1N1, A/H3N2 and B antibodies against influenza virus were measured using micro-hemagglutination inhibition (HI) assay. RESULTS: A total of 130 subjects were recruited and 120 paired serum samples were obtained. The overall rate of adverse events was 2.3% (3/130) and all of them with systemic reaction. No single serious adverse event was reported. 21 days after the vaccination, the sero-conversion rates of A/H1N1, A/H3N2 and B antibodies against influenza virus among adults were 82.5%, 93.7% and 92.1%, respectively. The Geometric Mean Titer (GMT) ratios were 20.2, 32.0 and 11.4, while the sero-protection rates were 92.1%, 98.4% and 98.4%, respectively. The sero-conversion rates of antibodies among elders were 89.5%, 91.2% and 87.7%, with the GMT ratios as 23.9, 39.8 and 15.1, respectively. The sero-protection rates were 93.0%, 94.7% and 96.5%, respectively. CONCLUSION: All indexes of A/H1N1, A/H3N2 and B antibodies exceeded the licensure criteria established by the EU Committee for Medicinal Products for Human Use, proving the trial vaccine Anflu(®) with good safety and immunogenicity.


Assuntos
Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza B/imunologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Int J Nanomedicine ; 5: 437-44, 2010 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-20957165

RESUMO

In many instances, multidrug resistance (MDR) is mediated by increasing the expression at the cell surface of the MDR1 gene product, P-glycoprotein (P-gp), a 170-kD energy-dependent efflux pump. The aim of this study was to investigate the potential benefit of combination therapy with magnetic Fe(3)O(4) nanoparticle [MNP (Fe(3)O(4))] and MDR1 shRNA expression vector in K562/A02 cells. For stable reversal of "classical" MDR by short hairpin RNA (shRNA) aiming directly at the target sequence (3491-3509, 1539-1557, and 3103-3121 nucleotide) of MDR1 mRNA. PGC silencer-U6-neo-GFP-shRNA/MDR1 called PGY1-1, PGY1-2, and PGY1-3 were constructed and transfected into K562/A02 cells by lipofectamine 2000. After transfected and incubated with or without MNP (Fe(3)O(4)) for 48 hours, the transcription of MDR1 mRNA and the expression of P-gp were detected by quantitative real-time PCR and Western-blot assay respectively. Meanwhile intracellular concentration of DNR in K562/A02 cells was detected by flow cytometry (FCM). PGC silencer-U6-neo-GFP-shRNA/MDR1 was successfully constructed, which was confirmed by sequencing and PGY1-2 had the greatest MDR1 gene inhibitory ratio. Analysis of the reversal ratio of MDR, the concentration of daunorubicin (DNR) and the transcription of MDR1 gene and expression of P-gp in K562/A02 showed that combination of DNR with either MNP (Fe(3)O(4)) or PGY1-2 exerted a potent cytotoxic effect on K562/A02 cells, while combination of MNP (Fe(3)O(4)) and PGY1-2 could synergistically reverse multidrug resistance. Thus our in vitro data strongly suggested that a combination of MNP (Fe(3)O(4)) and shRNA expression vector might be a more sufficient and less toxic anti-MDR method on leukemia.


Assuntos
Daunorrubicina/administração & dosagem , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Genes MDR , Nanopartículas de Magnetita/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Antibióticos Antineoplásicos/administração & dosagem , Sequência de Bases , Primers do DNA/genética , Doxorrubicina/administração & dosagem , Vetores Genéticos , Humanos , Células K562 , Dados de Sequência Molecular , Nanomedicina , Transfecção
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 18(1): 67-73, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20137121

RESUMO

This study was aimed to explore the potential therapy of Gambogic acid (GA) combined with magnetic nanoparticle of Fe3O4 (Fe3O4-MNP) on leukemia. The proliferation of U937 cells and the cytotoxicity were evaluated by MTT assay. Cell apoptosis was observed and analyzed by microscopy and flow cytometry respectively. The expressions of gene and protein were detected by quantitative real-time polymerase chain reaction and Western blot respectively. The results showed that GA enhanced the cytotoxicity for U937 cells in dose- and time-dependent manners. The Fe3O4-MNP itself had not cytotoxicity, but could enhance the inhibitory effect of GA on proliferation of U937 cells. The apoptotic rate of U937 cells induced by combination of GA with Fe3O4-MNP was higher than that by GA alone. The typical apoptotic features of cells treated with GA and Fe3O4-MNP were observed. The expression levels of caspase-3 and bax after co-treatment of GA and Fe3O4-MNP were higher than that exposed to GA or Fe3O4-MNP alone, but the expressions of bcl-2, NF-kappaB and survivin were down-regulated. It is concluded that Fe3O4-MNP can promote GA-induced apoptosis in U937 cells, and the combination of GA with Fe3O4-MNP may be a safer and less toxic new therapy for leukemia.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Ferro/administração & dosagem , Compostos de Ferro/farmacologia , Xantonas/farmacologia , Humanos , Magnetismo , Nanopartículas , Células U937
16.
Int J Nanomedicine ; 4: 201-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19918366

RESUMO

Multidrug resistance (MDR) is a major obstacle to cancer chemotherapy. We evaluated the effect of daunorubicin (DNR)-loaded magnetic nanoparticles of Fe3O4 (MNPs-Fe3O4) on K562-n/VCR cells in vivo. K562-n and its MDR counterpart K562-n/VCR cell were inoculated into nude mice subcutaneously. The mice were randomly divided into four groups: group A received normal saline, group B received DNR, group C received MNPs-Fe3O4, and group D received DNR-loaded MNPs-Fe3O4. For K562-n/VCR tumor, the weight was markedly lower in group D than that in groups A, B, and C. The transcriptions of Mdr-1 and Bcl-2 gene were significantly lower in group D than those in groups A, B, and C. The expression of Bcl-2 was lower in group D than those in groups A, B, and C, but there was no difference in the expression of P-glycoprotein. The transcriptions and expressions of Bax and caspase-3 in group D were increased significantly when compared with groups A, B, and C. In conclusion, DNR-loaded MNPs-Fe3O4 can overcome MDR in vivo.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Daunorrubicina/administração & dosagem , Óxido Ferroso-Férrico/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Animais , Sequência de Bases , Primers do DNA/genética , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Experimental/tratamento farmacológico , Leucemia Experimental/genética , Leucemia Experimental/patologia , Magnetismo , Camundongos , Camundongos Nus , Nanomedicina , Transplante de Neoplasias , RNA Neoplásico/genética , Transplante Heterólogo
17.
Ai Zheng ; 28(11): 1158-62, 2009 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19895735

RESUMO

BACKGROUND AND OBJECTIVE: Resistance to cisplatin (DDP) remains a major obstacle for the successful treatment of ovarian cancer. This study was to determine the reversal effect of Fe3O4-magnetic nanoparticles (MNPs) on DDP-resistance of ovarian carcinoma cell line SKOV3/DDP, and to explore its correlation with apoptosis-associated genes. METHODS: SKOV3/DDP cells were divided into the DDP group, the Fe3O4-MNPs group, the combination (DDP plus Fe3O4-MNPs) group, and the control group. Cell proliferation was determined by MTT assay. Cell apoptosis was analyzed by flow cytometry (FCM). Intracellular DDP level was detected by inductively coupled plasma atomic emission spectrometry (ICP-AES). The expressions of apoptosis-associated genes, bcl-2, and survivin were detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Fe3O4-MNPs reversed DDP-resistance of SKOV3/DDP cells by 2.259 folds. The cell apotosis rate and the intracellular DDP level were significantly higher in the combination group than in the DDP group (P<0.05). Moreover, the mRNA levels of bcl-2 and survivin were significantly lower in the combination group than in the DDP group(P<0.05). CONCLUSIONS: Fe3O4-MNPs can reverse the DDP resistance of ovarian carcinoma SKOV3/DDP cells, and the effect may be ascribed to the down-regulation of bcl-2 and survivin expression.


Assuntos
Cisplatino/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Compostos Férricos/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Proteínas Inibidoras de Apoptose/genética , Magnetismo , Nanopartículas , Neoplasias Ovarianas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Survivina
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(5): 1183-91, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19840447

RESUMO

The present study was aimed to evaluate the MDR reversal activity of bromotetrandrine (BrTet) in vitro and in vivo. The inhibitory effects of adriamycin (ADM) used alone or in combination with BrTet or Tet on the proliferation of K562 and K562/A02 cells were evaluated by MTT assay. The ADM accumulation and the protein levels of P-glycoprotein (P-gp) were detected by flow cytometry. The mRNA levels of P-gp were determined by RT-PCR. The in vivo effect of BrTet and Tet was investigated by using nude mice grafted with sensitive human leukemia cell line K562 and MDR cell line K562/A02. The results showed that BrTet at 0.25, 0.5 and 1 micromol/L reversed the resistance to ADM in MDR K562/A02 cells in a dose-dependent manner. Flow cytometry suggested that BrTet significantly increased the intracellular accumulation of ADM in K562/A02 cells in a dose-dependent manner. BrTet also inhibited the overexpression of P-gp in K562/A02 cells, and down-regulated mdr1 expression. In nude mice bearing K562 xenografts on the left flank and K562/A02 xenografts on the right flank, intraperitoneal injection of 10 mg/kg BrTet significantly enhanced the antitumor activity of ADM against K562/A02 xenografts with inhibitory rates of 26.1%, while ADM alone inhibited the growth of K562/A02 xenografts only by 5.8%. No enhancement effect by BrTet was seen in K562 xenografts. It is concluded that BrTet shows significant MDR reversal activity in vitro and in vivo. Its activity may be related to the inhibition of P-gp overexpression and the increase intracellular accumulation of anticancer drugs. BrTet may be a promising-MDR modulator for eventual assessment in the clinic.


Assuntos
Benzilisoquinolinas/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Células K562 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Int J Nanomedicine ; 4: 107-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19516889

RESUMO

To explore whether the magnetic nanoparticles of Fe3O4 (MNPs-Fe3O4) loaded with cisplatin can reverse the diaminedichloro platinum (DDP) resistance to multidrug resistance of ovarian carcinoma cells and to investigate its mechanisms. The SKOV3/DDP cells were divided into DDP treatment (DDP group), MNPs-Fe3O4 treatment (MNPs-Fe3O4 group), DDP + MNPs-Fe3O4 treatment (DDP + MNPs-Fe3O4 group), and control group. After incubation with those conjugates for 48 h, the cytotoxic effects were measured by MTT assay. Apoptosis and the intracellular DDP concentration were investigated by flow cytometry and inductively coupled plasma atomic emission spectroscopy, respectively. The expression of apoptosis associated gene Bcl-2 mRNA was detected by reverse transcription polymerase chain reaction and the expressions of MDR1, lung resistance-related protein (LRP), and P-glycoprotein (P-gp) genes were studied by Western blot. Our results indicated that the 50% inhibition concentration (IC50) of the MNPs-Fe3O4 loaded with DDP was 17.4 micromol/l, while the IC50 was 39.31 micromol/l in DDP groups (p < 0.05); Apoptosis rates of SKOV3/DDP cells increased more than those of DDP groups. Accumulation of intracellular cisplatin in DDP + MNPs-Fe3O4 groups was higher than those in DDP groups (p < 0.05). Moreover, the expression of Bcl-2 mRNA and the protein expressions of MDR1, LRP, and P-gp were decreased when compared with those of DDP groups, respectively. Our results suggest that MNPs-Fe3O4 can reverse the DDP resistance to the ovarian carcinoma cell. The effects may be associated with over-expression of MDR1, LRP, P-gp, and Bcl-2, which can increase the intracellular platinum accumulation and induce the cell apoptosis.


Assuntos
Cisplatino/administração & dosagem , Portadores de Fármacos/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Compostos Férricos/química , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Magnetismo , Nanopartículas/ultraestrutura , Resultado do Tratamento
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 17(2): 345-51, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19379564

RESUMO

Multidrug resistance (MDR) plays a major role in the failure of cancer chemotherapy. Since Fe(3)O(4)-magnetic nanoparticle loaded with daunorubicin (DNR) can overcome multidrug-resistance of K562 cells in vitro, the effect of Fe(3)O(4)-magnetic nanoparticle loaded with DNR on multidrug-resistant K562 cells was studied in vivo, the K562-n and its MDR counterpart K562-n/VCR cells were inoculated subcutaneously into both sides of the back of nude mice to establish a human leukemia xenograft model. The mice were randomly divided into group A receiving normal saline, group B receiving DNR, group C receiving Fe(3)O(4)-magnetic nanoparticle, group D receiving Fe(3)O(4)-magnetic nanoparticle loaded with DNR and group E receiving Fe(3)O(4)-magnetic nanoparticle containing DNR with a magnetic field built on the surface of the tumor tissue. The tumor volume was measured on the day 1, 5, 9, 13, 17 and 21 after the first treatment. Tumor tissues were isolated for examination of the expression of mdr-1 by reverse transcription polymerase chain reaction and Western blotting. The results showed that for K562-n/VCR tumor, the tumor volume was markedly lower in groups D and E than that in groups A, B and C. Pathological observation revealed that the tumor cells of group A and B grew well, some disseminated necrosis and some cells with karyorrhexis and karyopyknosis existed in group C. However, significant fracture, necrosis of cell and subsequently fibrosis were seen in group D and E. The transcription of mdr-1 gene in groups D and E was significantly lower than that in groups A, B and C (group D and E vs group A, B or C, p < 0.05). However, there were no differences about the protein expression of P-gp between these groups. The tumor volume of K562-n in groups C, D and E was markedly lower than that in groups A and B (group C, D and E vs group A or B, p < 0.05). Pathological observation showed that the tumor cell of group A and B grew well, and no obvious necrosis was observed. Significant fracture, necrosis of cell and subsequently fibrosis were seen in group C, D and E. It is concluded that DNR-loaded Fe(3)O(4) magnetic nanoparticles can suppress the growth of the MDR K562-n/VCR tumor in vivo, but can not further enhance its efficacy on the sensitive K562-n tumor as compared to DNR alone. The additional external magnetic field failed to further improve the antitumor effect in vivo.


Assuntos
Daunorrubicina/administração & dosagem , Daunorrubicina/uso terapêutico , Leucemia/tratamento farmacológico , Animais , Daunorrubicina/farmacologia , Portadores de Fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Células K562 , Magnetismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
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