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1.
Int J Nanomedicine ; 12: 6503-6520, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28919751

RESUMO

BACKGROUND: Breast cancer is the most common malignant disease that occurs in women. Histone deacetylase (HDAC) inhibition has recently emerged as an effective and attractive target for the treatment of cancer. The aim of this study was to investigate the efficacy of a combined treatment of tubastatin A (TUB-A) and palladium nanoparticles (PdNPs) against MDA-MB-231 human breast cancer cells using two different cytotoxic agents that work by two different mechanisms, thereby decreasing the probability of chemoresistance in cancer cells and increasing the efficacy of toxicity, to provide efficient therapy for advanced stage of cancer without any undesired side effects. METHODS: PdNPs were synthesized using a novel biomolecule called R-phycoerythrin and characterized using various analytical techniques. The combinatorial effect of TUB-A and PdNPs was assessed by various cellular and biochemical assays and also by gene expression analysis. RESULTS: The biologically synthesized PdNPs had an average size of 25 nm and were spherical in shape. Treatment of MDA-MB-231 human breast cancer cells with TUB-A or PdNPs showed a dose-dependent effect on cell viability. The combination of 4 µM TUB-A and 4 µM PdNPs had a significant inhibitory effect on cell viability compared with either TUB-A or PdNPs alone. The combinatorial treatment also had a more pronounced effect on the inhibition of HDAC activity and enhanced apoptosis by regulating various cellular and biochemical changes. CONCLUSION: Our results suggest that there was a strong synergistic interaction between TUB-A and PdNPs in increasing apoptosis in human breast cancer cells. These data provide an important preclinical basis for future clinical trials on this drug combination. This combinatorial treatment increased therapeutic potentials, thereby demonstrating a relevant targeted therapy for breast cancer. Furthermore, we have provided the first evidence for the combinatorial effect and mechanism of toxicity of TUB-A and PdNPs in human breast cancer cells. The novelties of the study were identification of a combination therapy that consists of suitable therapeutic molecules that kill cancer cells and also exploration of two different possible mechanisms involved to reduce chemoresistance in cancer cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Nanopartículas Metálicas/administração & dosagem , Paládio/química , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Feminino , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/química , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/química , Indóis/administração & dosagem , Indóis/química , Nanopartículas Metálicas/química , Paládio/farmacologia , Ficoeritrina/química , Extratos Vegetais/química
2.
Int J Nanomedicine ; 12: 6487-6502, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28919750

RESUMO

BACKGROUND: Gemcitabine (GEM) is widely used as an anticancer agent in several types of solid tumors. Silver nanoparticles (AgNPs) possess unique cytotoxic features and can induce apoptosis in a variety of cancer cells. In this study, we investigated whether the combination of GEM and AgNPs can exert synergistic cytotoxic effects in the human ovarian cancer cell line A2780. METHODS: We synthesized AgNPs using resveratrol as a reducing and stabilizing agent. The synthesized nanomaterials were characterized using various analytical techniques. The anticancer effects of a combined treatment with GEM and AgNPs were evaluated using a series of cellular assays. The expression of pro- and antiapoptotic genes was measured using real-time reverse transcription polymerase chain reaction. Apoptosis was confirmed by TUNEL assay. RESULTS: In this study, combined treatment with GEM and AgNPs significantly inhibited viability and proliferation in A2780 cells. Moreover, the levels of apoptosis in cells treated with a combination of GEM and AgNPs were significantly higher compared with those in cells treated with GEM or AgNPs alone. Our data suggest that GEM and AgNPs exhibit potent apoptotic activity in human ovarian cancer cells. Combined treatment with GEM and AgNPs showed a significantly higher cytotoxic effect in ovarian cancer cells compared with that induced by either of these agents alone. CONCLUSION: Our study demonstrated that the interaction between GEM and AgNPs was cytotoxic in ovarian cancer cells. Combined treatment with GEM and AgNPs caused increased cytotoxicity and apoptosis in A2780 cells. This treatment may have therapeutic potential as targeted therapy for the treatment of ovarian cancer. To our knowledge, this study could provide evidence that AgNPs can enhance responsiveness to GEM in ovarian cancer cells and that AgNPs can potentially be used as chemosensitizing agents in ovarian cancer therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Nanopartículas Metálicas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/química , Neoplasias Ovarianas/patologia , Resveratrol , Prata/administração & dosagem , Prata/farmacologia , Estilbenos/química , Gencitabina
3.
Molecules ; 22(8)2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-28758981

RESUMO

An efficient base-catalyzed synthesis of arylated pyridines has been disclosed. This reaction involving conjugated acetylenes and substituted benzylamines proceeded smoothly, giving rise to tri-aryl substituted pyridines which are biologically relevant compounds in good to excellent yields in N,N-dimethylformamide (DMF) under air at 140 °C with K2CO3 as catalyst.


Assuntos
Alcinos/química , Benzilaminas/química , Piridinas/química , Piridinas/síntese química , Carbonatos/química , Catálise , Potássio/química
4.
Int J Mol Sci ; 18(3)2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28272303

RESUMO

Recently, silver nanoparticles (AgNPs) have been widely used in various applications as antimicrobial agents, anticancer, diagnostics, biomarkers, cell labels, and drug delivery systems for the treatment of various diseases. Microorganisms generally acquire resistance to antibiotics through the course of antibacterial therapy. Multi-drug resistance (MDR) has become a growing problem in the treatment of infectious diseases, and the widespread use of broad-spectrum antibiotics has resulted in the development of antibiotic resistance by numerous human and animal bacterial pathogens. As a result, an increasing number of microorganisms are resistant to multiple antibiotics causing continuing economic losses in dairy farming. Therefore, there is an urgent need for the development of alternative, cost-effective, and efficient antimicrobial agents that overcome antimicrobial resistance. Here, AgNPs synthesized using the bio-molecule quercetin were characterized using various analytical techniques. The synthesized AgNPs were highly spherical in shape and had an average size of 11 nm. We evaluated the efficacy of synthesized AgNPs against two MDR pathogenic bacteria, namely, Pseudomonas aeruginosa and Staphylococcus aureus, which were isolated from milk samples produced by mastitis-infected goats. The minimum inhibitory concentrations (MICs) of AgNPs against P. aeruginosa and S. aureus were found to be 1 and 2 µg/mL, respectively. Our findings suggest that AgNPs exert antibacterial effects in a dose- and time-dependent manner. Results from the present study demonstrate that the antibacterial activity of AgNPs is due to the generation of reactive oxygen species (ROS), malondialdehyde (MDA), and leakage of proteins and sugars in bacterial cells. Results of the present study showed that AgNP-treated bacteria had significantly lower lactate dehydrogenase activity (LDH) and lower adenosine triphosphate (ATP) levels compared to the control. Furthermore, AgNP-treated bacteria showed downregulated expression of glutathione (GSH), upregulation of glutathione S-transferase (GST), and downregulation of both superoxide dismutase (SOD) and catalase (CAT). These physiological and biochemical measurements were consistently observed in AgNP-treated bacteria, thereby suggesting that AgNPs can induce bacterial cell death. Thus, the above results represent conclusive findings on the mechanism of action of AgNPs against different types of bacteria. This study also demonstrates the promising use of nanoparticles as antibacterial agents for use in the biotechnology and biomedical industry. Furthermore, this study is the first to propose the mode of action of AgNPs against MDR pathogens isolated from goats infected with subclinical mastitis.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Mastite/veterinária , Nanopartículas Metálicas/uso terapêutico , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Animais , Feminino , Cabras , Mastite/tratamento farmacológico , Mastite/microbiologia , Nanopartículas Metálicas/química , Estresse Oxidativo , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/metabolismo , Quercetina/química , Quercetina/uso terapêutico , Prata/química , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/metabolismo
5.
Sci China C Life Sci ; 51(7): 614-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18622744

RESUMO

Neonatal diarrhea caused by enterotoxigenic Escherichia coli (ETEC) F4 is a common and serious disease, resulting in significant economical loss in the pig industry. The locus encoding ETEC F4 receptor has been mapped to pig chromosome (SSC) 13q41, and one of the most significantly linked markers is S0075. In this study, we selected three genes including SLC12A8, MYLK and KPNA1 from a chromosomal region flanking S0075 on SSC13 to develop pig specific sequence tagged sites (STS). Seven single nucleotide polymorphisms were identified in the three pig STS using DNA of four full-sib susceptible and resistant animals in a White Duroc x Erhualian intercross. All grandparents, parents and 755 offspring in the intercross were genotyped for three polymorphisms, including SLC12A8 g.159A>G, MYLK g.1673A>G and KPNA1 g.306A>G. Family-based transmission disequilibrium test (TDT) revealed that all polymorphisms and the corresponding haplotypes are significantly associated with ETEC F4ab/ac (especially F4ac) brush border adhesion phenotypes, indicating that these polymorphism are in linkage disequlibrium with causal mutation(s) of the gene encoding ETEC F4ab/ac receptor. Our results strengthen the evidence for the involvement of SSC13q41 in high acquiring risk of ETEC F4ab/ac infection, and provide novel polymorphic markers for fine mapping of the ETEC F4ab/ac receptor locus.


Assuntos
Cromossomos de Mamíferos/genética , Escherichia coli Enterotoxigênica/classificação , Infecções por Escherichia coli/veterinária , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Sitios de Sequências Rotuladas , Suínos/genética , Animais , Sequência de Bases , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/genética , Genótipo , Fenótipo
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