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1.
Sci Rep ; 7: 42108, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28176838

RESUMO

N,N-Dimethylacetamide (DMA) is a water-miscible solvent, FDA approved as excipient and therefore widely used as drug-delivery vehicle. As such, DMA should be devoid of any bioactivity. Here we report that DMA is epigenetically active since it binds bromodomains and inhibits osteoclastogenesis and inflammation. Moreover, DMA enhances bone regeneration in vivo. Therefore, our in vivo and in vitro data reveal DMA's potential as an anti-osteoporotic agent via the inhibition of osteoclast mediated bone resorption and enhanced bone regeneration. Our results highlight the potential therapeutic benefits of DMA and the need for reconsideration of previous reports where DMA was used as an 'inactive' drug-delivery vehicle.


Assuntos
Acetamidas/farmacologia , Anti-Inflamatórios/farmacologia , Conservadores da Densidade Óssea/farmacologia , Excipientes/farmacologia , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ciclo Celular , Linhagem Celular , Feminino , Humanos , Camundongos , Osteogênese/efeitos dos fármacos , Ligação Proteica , Ratos Sprague-Dawley
2.
J Tissue Eng Regen Med ; 11(2): 425-433, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-24919954

RESUMO

Guided bone regeneration (GBR) has been utilized for several decades for the healing of cranio-maxillofacial bone defects and, particularly in the dental field, by creating space with a barrier membrane to exclude soft tissue and encourage bone growth in the membrane-protected volume. Although the first membranes were non-resorbable, a new generation of GBR membranes aims to biodegrade and provide bioactivity for better overall results. The Inion GTR™ poly(lactide-co-glycolide) (PLGA) membrane is not only resorbable but also bioactive, since it includes N-methylpyrrolidone (NMP), which has been shown to promote bone regeneration. In this study, the effects of loading different amounts of NMP onto the membrane through chemical vapour deposition or dipping have been explored. In vitro release demonstrated that lower levels of NMP led to lower NMP concentrations and slower release, based on total NMP loaded in the membrane. The dipped membrane released almost all of the NMP within 15 min, leading to a high NMP concentration. For the in vivo studies in rabbits, 6 mm calvarial defects were created and left untreated or covered with an ePTFE membrane or PLGA membranes dipped in, or preloaded with, NMP. Evaluation of the bony regeneration revealed that the barrier membranes improved bony healing and that a decrease in NMP content improved the performance. Overall, we have demonstrated the potential of these PLGA membranes with a more favourable NMP release profile and the significance of exploring the effect of NMP on these PLGA membranes with regard to bone ingrowth. Copyright © 2014 John Wiley & Sons, Ltd.


Assuntos
Implantes Absorvíveis , Regeneração Óssea/efeitos dos fármacos , Regeneração Tecidual Guiada/métodos , Ácido Láctico/química , Ácido Poliglicólico/química , Pirrolidinonas/química , Animais , Materiais Biocompatíveis/química , Substitutos Ósseos/química , Membranas Artificiais , Microscopia Eletrônica de Varredura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos
3.
Tissue Eng Part A ; 23(3-4): 115-123, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27762658

RESUMO

Conventional root canal treatment in immature permanent teeth can lead to early tooth loss in children because root formation is discontinued. We investigated whether the stem cell factor (SCF) could facilitate cell homing in the pulpless immature root canal and promote regeneration of a functional pulp. In vitro, human mesenchymal stem cells (hMSCs) were exposed to SCF at various concentrations for assessing cell migration, proliferation, and differentiation toward odonto/osteoblasts by 3D-chemotaxis slides, WST-1 assay, and alkaline phosphatase activity, respectively. Fibrin gels were used to deliver 15 µg/mL SCF for in vivo experiments. The release kinetic of SCF was assessed in vitro. Two corresponding human immature premolars, with or without SCF, were placed at rat calvariae for 6 and 12 weeks. All tooth specimens were either analyzed histologically and the percentage of tissue ingrowth determined or the cells were extracted from the pulp space, and the mRNA level of DMP1, DSPP, Col1, NGF, and VEGF were assessed by quantitative polymerase chain reaction. In the presence of SCF, we saw an increase in hMSCs directional migration, proliferation, and odonto/osteogenic differentiation. SCF also increased the extent of tissue ingrowth at 6 weeks but not at 12 weeks. However, at this time point, the formed tissue appeared more mature in samples with SCF. In terms of gene transcription, DMP1, Col1, and VEGF were the significantly upregulated genes, while DSPP and NGF were not affected. Our results suggest that SCF can accelerate cell homing and the maturation of the pulp-dentin complex in human immature teeth.


Assuntos
Dente Pré-Molar , Movimento Celular/efeitos dos fármacos , Polpa Dentária/metabolismo , Células-Tronco Mesenquimais/metabolismo , Regeneração/efeitos dos fármacos , Fator de Células-Tronco/farmacologia , Adolescente , Dente Pré-Molar/lesões , Dente Pré-Molar/fisiologia , Criança , Polpa Dentária/citologia , Feminino , Humanos , Masculino , Regulação para Cima/efeitos dos fármacos
4.
Clin Epigenetics ; 8: 42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110299

RESUMO

BACKGROUND: Weight gain is one of the consequences of estrogen deficiency and constitutes a major health problem. The present study highlights the effects of N-methyl pyrrolidone (NMP) on adipogenesis in osteoporosis induced by estrogen deficiency in an ovariectomized rat model. RESULTS: Ovariectomy resulted in body weight gain, increased femoral marrow adipocytes, and hypertrophic adipocytes in white adipose tissue, distorted serum leptin, and TNF-α and PPARγ levels. Treatment with NMP normalized these parameters similar to the control group. In vitro, NMP inhibited the differentiation of 3T3-L1 pre-adipocytes and hMSCs, indicating its anti-adipogenic effect. Moreover, PPARγ was significantly reduced with NMP treatment in in vivo and in vitro experiments. NMP inhibited BRD2 and BRD4 binding in an AlphaScreen assay, with an IC50 of 3 and 4 mM, respectively. The effect of NMP was consistent with its role as a bromodomain inhibitor. CONCLUSIONS: Our data indicates that NMP inhibits the adipogenic effect of estrogen deficiency at the level of PPARγ expression by BRD4 inhibition.


Assuntos
Adipócitos/efeitos dos fármacos , Osteoporose/etiologia , Ovariectomia/efeitos adversos , Pirrolidinonas/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipogenia/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proteínas Cromossômicas não Histona/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Proteínas Nucleares/metabolismo , Osteoporose/complicações , Osteoporose/metabolismo , Ligação Proteica/efeitos dos fármacos , Pirrolidinonas/farmacologia , Ratos , Fatores de Transcrição/metabolismo
5.
Inflamm Res ; 64(7): 527-36, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26047594

RESUMO

OBJECTIVE: N-methyl pyrrolidone (NMP), a small bioactive molecule, stimulates bone formation and inhibits osteoclast differentiation and bone resorption. The present study was aimed to evaluate the anti-inflammatory potentials of NMP on the inflammatory process and the underlying molecular mechanisms in RAW264.7 macrophages. MATERIALS AND METHODS: RAW264.7 macrophages and mouse primary bone marrow macrophages (mBMMs) were used as an in vitro model to investigate inflammatory processes. Cells were pre-treated with or without NMP and then stimulated with lipopolysaccharides (LPS). The productions of cytokines and NO were determined by proteome profiler method and nitrite analysis, respectively. The expressions of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were measured by Western blotting and/or qPCR. Western blot, ELISA-base reporter assay, and immunofluorescence were used to evaluate the activation of MAP kinases and NF-κB. RESULTS: LPS-induced mRNA expressions of TNF-α, IL-1ß, IL-6, iNOS, and COX-2 were inhibited by NMP in a dose-dependent manner. NMP also suppressed the LPS-increased productions of iNOS and NO. The proteome profiler array showed that several cytokines and chemokines involved in inflammation and up-regulated by LPS stimulation were significantly down-regulated by NMP. Additionally, this study shows that the effect of NMP is mediated through down-regulation of NFκB pathway. CONCLUSIONS: Our results show that NMP inhibits the inflammatory mediators in macrophages by an NFκB-dependent mechanism, based on the epigenetical activity of NMP as bromodomain inhibitor. In the light of its action on osteoblast and osteoclast differentiation process and its anti-inflammatory potential, NMP might be used in inflammation-related bone loss.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Lipopolissacarídeos/antagonistas & inibidores , NF-kappa B/efeitos dos fármacos , Pirrolidinonas/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/biossíntese , Citocinas/biossíntese , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Células RAW 264.7/efeitos dos fármacos , Fator de Transcrição RelA/biossíntese
6.
Bone ; 78: 114-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25959414

RESUMO

Currently, there are several treatments for osteoporosis however; they all display some sort of limitation and/or side effects making the need for new treatments imperative. We have previously demonstrated that NMP is a bioactive drug which enhances bone regeneration in vivo and acts as an enhancer of bone morphogenetic protein (BMP) in vitro. NMP also inhibits osteoclast differentiation and attenuates bone resorption. In the present study, we tested NMP as a bromodomain inhibitor and for osteoporosis prevention on ovariectomized (OVX) induced rats while treated systemically with NMP. Female Sprague-Dawley rats were ovariectomized and weekly NMP treatment was administrated 1 week after surgery for 15 weeks. Bone parameters and related serum biomarkers were analyzed. 15 weeks of NMP treatment decreased ovariectomy-induced gained weight in average by 43% and improved bone mineral density (BMD) and bone volume over total volume (BV/TV) in rat femur on average by 25% and 41% respectively. Moreover, mineral apposition rate and bone biomarkers of bone turnover in the treatment group were at similar levels with those of the Sham group. Due to the function of NMP as a low affinity bromodomain inhibitor and its mechanism of action involving osteoblasts/osteoclasts balance and inhibitory effect on inflammatory cytokines, NMP is a promising therapeutic compound for the prevention of osteoporosis.


Assuntos
Epigênese Genética , Estrogênios/química , Osteoporose/prevenção & controle , Pirrolidinonas/química , Fosfatase Alcalina/metabolismo , Animais , Peso Corporal , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea , Reabsorção Óssea , Osso e Ossos/patologia , Diferenciação Celular , Feminino , Fêmur/patologia , Imageamento Tridimensional , Microscopia de Fluorescência , Osteoblastos/citologia , Osteoclastos/citologia , Osteoporose/induzido quimicamente , Ovariectomia , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
7.
Environ Microbiol ; 17(1): 91-104, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24803113

RESUMO

Pseudomonas knackmussii B13 was the first strain to be isolated in 1974 that could degrade chlorinated aromatic hydrocarbons. This discovery was the prologue for subsequent characterization of numerous bacterial metabolic pathways, for genetic and biochemical studies, and which spurred ideas for pollutant bioremediation. In this study, we determined the complete genome sequence of B13 using next generation sequencing technologies and optical mapping. Genome annotation indicated that B13 has a variety of metabolic pathways for degrading monoaromatic hydrocarbons including chlorobenzoate, aminophenol, anthranilate and hydroxyquinol, but not polyaromatic compounds. Comparative genome analysis revealed that B13 is closest to Pseudomonas denitrificans and Pseudomonas aeruginosa. The B13 genome contains at least eight genomic islands [prophages and integrative conjugative elements (ICEs)], which were absent in closely related pseudomonads. We confirm that two ICEs are identical copies of the 103 kb self-transmissible element ICEclc that carries the genes for chlorocatechol metabolism. Comparison of ICEclc showed that it is composed of a variable and a 'core' region, which is very conserved among proteobacterial genomes, suggesting a widely distributed family of so far uncharacterized ICE. Resequencing of two spontaneous B13 mutants revealed a number of single nucleotide substitutions, as well as excision of a large 220 kb region and a prophage that drastically change the host metabolic capacity and survivability.


Assuntos
Genoma Bacteriano , Pseudomonas/genética , Clorobenzoatos/metabolismo , Cromossomos Bacterianos , Ilhas Genômicas , Genômica , Hidrocarbonetos Aromáticos/metabolismo , Redes e Vias Metabólicas , Prófagos/genética , Pseudomonas/classificação , Pseudomonas/metabolismo , Pseudomonas aeruginosa/genética
8.
J Virol ; 86(11): 6279-85, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22491454

RESUMO

Adenovirus serotype 5 (Ad5) vectors and specific neutralizing antibodies (NAbs) generate immune complexes (ICs) which are potent inducers of dendritic cell (DC) maturation. Here we show that ICs generated with rare Ad vector serotypes, such as Ad26 and Ad35, which are lead candidates in HIV vaccine development, are poor inducers of DC maturation and that their potency in inducing DC maturation strongly correlated with the number of Toll-like receptor 9 (TLR9)-agonist motifs present in the Ad vector's genome. In addition, we showed that antihexon but not antifiber antibodies are responsible for the induction of Ad IC-mediated DC maturation.


Assuntos
Adenovírus Humanos/genética , Adenovírus Humanos/imunologia , Complexo Antígeno-Anticorpo , Células Dendríticas/imunologia , Células Dendríticas/virologia , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/imunologia , Motivos de Aminoácidos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Humanos , Proteínas Virais/genética
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