Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Benef Microbes ; 15(3): 293-310, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38677716

RESUMO

Oral administration of probiotics has been proposed as a promising biotherapy to prevent and treat different diseases related to gastrointestinal disorders, such as irritable bowel syndrome (IBS). Due to the increasing research area on the characterisation of new probiotic bacterial strains, it is necessary to perform suitable in vitro experiments, using pertinent cellular models, in order to establish appropriate readout profiles based on IBS symptoms and subtypes. In this work, a collection of 30 candidate strains, belonging mainly to the Lactobacillus and Bifidobacterium genera, were screened using three different sets of in vitro experiments with different readouts to identify promising probiotic strains with: (1) the ability to inhibit the synthesis of IL-8 production by TNF-α stimulated HT-29 cells, (2) immunomodulatory properties quantified as increased IL-10 levels in peripheral blood mononuclear cell (PBMCs), and (3) the ability to maintain epithelial barrier integrity by increasing the trans-epithelial/endothelial electrical resistance (TEER) values in Caco-2 cells. Based on these criteria, three strains were selected: Lactobacillus gasseri PI41, Lacticaseibacillus rhamnosus PI48 and Bifidobacterium animalis subsp. lactis PI50, and tested in a murine model of low-grade inflammation induced by dinitrobenzene sulfonic acid (DNBS), which mimics some of the symptoms of IBS. Among the three strains, L. gasseri PI41 improved overall host well-being by preventing body weight loss in DNBS-treated mice and restored gut homeostasis by normalising the intestinal permeability and reducing pro-inflammatory markers. Therefore, the potential of this strain was confirmed in a second murine model known to reproduce IBS symptoms: the neonatal maternal separation (NMS) model. The PI41 strain was effective in preventing intestinal permeability and reducing colonic hypersensitivity. In conclusion, the set of in vitro experiments combined with in vivo assessments allowed us to identify a promising probiotic candidate strain, L. gasseri PI41, in the context of IBS.


Assuntos
Síndrome do Intestino Irritável , Probióticos , Probióticos/administração & dosagem , Probióticos/farmacologia , Síndrome do Intestino Irritável/terapia , Síndrome do Intestino Irritável/microbiologia , Humanos , Animais , Camundongos , Células CACO-2 , Células HT29 , Modelos Animais de Doenças , Leucócitos Mononucleares/imunologia , Lactobacillus/fisiologia , Interleucina-8/metabolismo , Bifidobacterium/fisiologia , Interleucina-10 , Lactobacillus gasseri , Lacticaseibacillus rhamnosus/fisiologia , Masculino , Bifidobacterium animalis/fisiologia
2.
Br J Oral Maxillofac Surg ; 59(5): 573-578, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33518396

RESUMO

The objective of this study was to assess the resorption index of particulate calvarial grafts in maxillary sinuses of patients undergoing total reconstruction of an atrophic maxilla with residual alveolar bone that was less than, or equal to, 3mm thick. Twenty-one maxillary sinus floor elevations were carried out using particulate calvarial grafts in 11 individuals with totally edentulous maxillas. All patients had computed tomography (CT) before (T0), and 48hours (T1) and six months after surgery (T2). For each CT scan, linear measurements were taken of sections of the anterior, medial, and posterior regions of the maxillary sinus. There was a significant increase in the height of the maxillary sinus floor when T0 was compared with T1 (p=0.001). There was a statistically significant reduction in all maxillary sinus measurements when T1 was compared with T2; the mean height reduction being 2.36mm (16.87%) in the anterior region, 3.53mm (22.47%) in the medial region, and 2.21mm (22.78%) in the posterior region (p=0.001). Mean resorption was 20.7%. Autogenous calvarial bone used alone is an option for graft material in pneumatised maxillary sinuses and in cases where there is limited alveolar bone.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Transplante Ósseo , Implantação Dentária Endóssea , Humanos , Maxila/diagnóstico por imagem , Maxila/cirurgia , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Estudos Prospectivos
3.
Brain Behav Immun ; 93: 226-237, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33516921

RESUMO

While toll-like receptors (TLRs), which mediate innate immunity, are known to play an important role in host defense, recent work suggest their involvement in some integrated behaviors, including anxiety, depressive and cognitive functions. Here, we investigated the potential involvement of the flagellin receptor, TLR5, in anxiety, depression and cognitive behaviors using male TLR5 knock-out (KO) mice. We aobserved a specific low level of basal anxiety in TLR5 KO mice with an alteration of the hypothalamo-pituitary axis (HPA) response to acute restraint stress, illustrated by a decrease of both plasma corticosterone level and c-fos expression in the hypothalamic paraventricular nucleus where TLR5 was expressed, compared to WT littermates. However, depression and cognitive-related behaviors were not different between TLR5 KO and WT mice. Nor there were significant changes in the expression of some cytokines (IL-6, IL-10 and TNF-α) and other TLRs (TLR2, TLR3 and TLR4) in the prefrontal cortex, amygdala and hippocampus of TLR5 KO mice compared to WT mice. Moreover, mRNA expression of BDNF and glucocorticoid receptors in the hippocampus and amygdala, respectively, was not different. Finally, acute intracerebroventricular administration of flagellin, a specific TLR5 agonist, or chronic neomycin treatment did not exhibit a significant main effect, only a significant main effect of genotype was observed between TLR5 KO and WT mice. Together, those findings suggest a previously undescribed and specific role of TLR5 in anxiety and open original prospects in our understanding of the brain-gut axis function.


Assuntos
Ansiedade , Receptor 5 Toll-Like , Animais , Ansiedade/genética , Transtornos de Ansiedade , Corticosterona , Masculino , Camundongos , Camundongos Knockout , Receptor 5 Toll-Like/genética
4.
Eur Biophys J ; 49(6): 473-484, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32813035

RESUMO

The aim of the present work was the biophysical characterization of the Amynthas gracilis hemoglobin (HbAg). The oxy-HbAg optical absorption data, with Soret and Q bands centered at 415, 540 and 575 nm, were stable and unchanged at pH 7.0. An increase in pH promotes decrease in the intensity in the optical absorption bands, suggesting an oligomeric dissociation and partial oxidation. Identical stability at pH 7.0 was observed in DLS results that presented a hydrodynamic diameter of 28 nm, characteristic of the whole oligomer. DLS shows that HbAg undergoes oligomeric dissociation and an aggregation/denaturation process that corroborates spectroscopic data. Our results showed that the monomer d presents four isoforms with molecular mass (MM) ranging from 16,244 to 16,855 Da; the trimer subunit presents two isoforms, (abc)1 and (abc)2, with MM of 51,415 ± 20 Da and 51,610 ± 14 Da, respectively, and a less intense species, at 67,793 Da, assigned to the tetramer abcd. Monomeric chains a, obtained from reduction of the disulfide-bonded trimer abc, present four isoforms with MM 17,015 Da, 17,061 Da, 17,138 Da and 17,259 Da. DLS and LSI revealed an isoeletric point (pI) of oxy-HbAg of 6.0 ± 0.3 and 5.5, respectively. Data analysis by IEF-SDS-PAGE revealed that the pI of oxy-HbAg is 6.11, correlating with DLS and LSI data. These studies indicate that oxy-HbAg is very stable, at pH 7.0, and has differing properties from orthologous giant hemoglobins.


Assuntos
Espaço Extracelular/metabolismo , Hemoglobinas/química , Hemoglobinas/metabolismo , Oligoquetos/citologia , Animais , Concentração de Íons de Hidrogênio , Peso Molecular
5.
Int J Oral Maxillofac Surg ; 47(9): 1219-1225, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29705405

RESUMO

Although there has been an increase in three-dimensional (3D) scanning methods available on the market, they are generally expensive. The DI3D system is considered a good scanner for the acquisition of soft tissue surface images. The Microsoft Kinect scanner is a much more affordable alternative for acquiring 3D models. The aim of this study was to determine whether the precision and accuracy of Kinect are similar to those of DI3D. To verify the accuracy, 10 patients were scanned with both methods The models of each patient acquired from the two scanners were superimposed using a surface-to-surface registration technique, and the distances between the models were recorded for 10 different anatomical regions of interest. For the evaluation of precision, one patient was scanned 11 different times with the Kinect scanner, and these models were compared using the same superimposition method. It was found that the average difference between the two methods was 0.3±2.03mm. The assessment of reproducibility showed an average difference between the images taken with Kinect of 0.1±0.6mm (P<0.05, one-sample t-test). Thus, Kinect showed good precision and reasonable accuracy, and appears to be an interesting and promising resource for facial analysis.


Assuntos
Face/anatomia & histologia , Imageamento Tridimensional/instrumentação , Adulto , Pontos de Referência Anatômicos/anatomia & histologia , Antropometria/instrumentação , Feminino , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Masculino , Reprodutibilidade dos Testes
6.
Hum Reprod ; 32(6): 1170-1182, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369509

RESUMO

STUDY QUESTION: Can all types of testicular germ cells be accurately identified by microscopy techniques and unambiguously distributed in stages of the human seminiferous epithelium cycle (SEC)? SUMMARY ANSWER: By using a high-resolution light microscopy (HRLM) method, which enables an improved visualization of germ cell morphological features, we identified all testicular germ cells in the seminiferous epithelium and precisely grouped them in six well-delimitated SEC stages, thus providing a reliable reference source for staging in man. WHAT IS ALREADY KNOWN: Morphological characterization of germ cells in human has been done decades ago with the use of conventional histological methods (formaldehyde-based fixative -Zenker-formal- and paraffin embedding). These early studies proposed a classification of the SEC in six stages. However, the use of stages as baseline for morphofunctional evaluations of testicular parenchyma has been difficult because of incomplete morphological identification of germ cells and their random distribution in the human SEC. STUDY DESIGN, SIZE, DURATION: Testicular tissue from adult and elderly donors with normal spermatogenesis according to Levin's, Johnsen's and Bergmann's scores were used to evaluate germ cell morphology and validate their distribution and frequency in stages throughout human spermatogenesis. PARTICIPANTS/MATERIALS, SETTING, METHODS: Testicular tissue from patients diagnosed with congenital bilateral agenesis of vas deferens (n = 3 adults) or prostate cancer (n = 3 elderly) were fixed in glutaraldehyde and embedded in araldite epoxy resin. Morphological analyses were performed by both light and transmission electron microscopy. MAIN RESULTS AND THE ROLE OF CHANCE: HRLM method enabled a reliable morphological identification of all germ cells (spermatogonia, spermatocytes and spermatids) based on high-resolution aspects of euchromatin, heterochromatin and nucleolus. Moreover, acrosomal development of spermatids was clearly revealed. Altogether, our data redefined the limits of each stage leading to a more reliable determination of the SEC in man. LIMITATIONS, REASONS FOR CAUTION: Occasionally, germ cells can be absent in some tubular sections. In this situation, it has to be taken into account the germ cell association proposed in the present study to classify the stages. WIDER IMPLICATIONS OF THE FINDINGS: Our findings bring a new focus on the morphology and development of germ cells during the SEC in human. Application of HRLM may be a valuable tool for research studies and clinical andrology helping to understand some testicular diseases and infertility conditions which remain unsolved. STUDY FUNDING/COMPETING INTEREST: Experiments were partially supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo à Pesquisa de Minas Gerais (FAPEMIG) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). The authors declare that there are no conflicts of interest. TRIAL REGISTRATION NUMBER: Not applicable.


Assuntos
Envelhecimento , Modelos Biológicos , Epitélio Seminífero/ultraestrutura , Espermatogênese , Espermatozoides/ultraestrutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Disgenesia Gonadal/patologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia , Microscopia Eletrônica de Transmissão , Orquiectomia , Tecido Parenquimatoso/citologia , Tecido Parenquimatoso/crescimento & desenvolvimento , Tecido Parenquimatoso/patologia , Tecido Parenquimatoso/ultraestrutura , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Epitélio Seminífero/citologia , Epitélio Seminífero/crescimento & desenvolvimento , Epitélio Seminífero/patologia , Espermatozoides/citologia , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/patologia , Testículo/anormalidades , Ducto Deferente/anormalidades
7.
Biomaterials ; 124: 211-224, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28209528

RESUMO

Macrophages are frequently identified in solid tumors, playing important roles in cancer progression. Their remarkable plasticity makes them very sensitive to environmental factors, including the extracellular matrix (ECM). In the present work, we investigated the impact of human colorectal tumor matrices on macrophage polarization and on macrophage-mediated cancer cell invasion. Accordingly, we developed an innovative 3D-organotypic model, based on the decellularization of normal and tumor tissues derived from colorectal cancer patients' surgical resections. Extensive characterization of these scaffolds revealed that DNA and other cell constituents were efficiently removed, while native tissue characteristics, namely major ECM components, architecture and mechanical properties, were preserved. Notably, normal and tumor decellularized matrices distinctly promoted macrophage polarization, with macrophages in tumor matrices differentiating towards an anti-inflammatory M2-like phenotype (higher IL-10, TGF-ß and CCL18 and lower CCR7 and TNF expression). Matrigel invasion assays revealed that tumor ECM-educated macrophages efficiently stimulated cancer cell invasion through a mechanism involving CCL18. Notably, the high expression of this chemokine at the invasive front of human colorectal tumors correlated with advanced tumor staging. Our approach evidences that normal and tumor decellularized matrices constitute excellent scaffolds when trying to recreate complex microenvironments to understand basic mechanisms of disease or therapeutic resistance.


Assuntos
Quimiocinas CC/imunologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Matriz Extracelular/química , Matriz Extracelular/imunologia , Macrófagos/imunologia , Microambiente Tumoral/imunologia , Polaridade Celular , Sistema Livre de Células , Neoplasias Colorretais/química , Humanos , Invasividade Neoplásica , Alicerces Teciduais , Células Tumorais Cultivadas
8.
Exp Parasitol ; 175: 59-67, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28189487

RESUMO

Myracrodruon urundeuva (Engl.) Fr. All., commonly known as "aroeira-do-sertão", is a medicinal plant from Anacardiaceae family. In this study, the chemical composition of M. urundeuva essential oil (MuEO) was evaluated by gas chromatography-mass spectrometry (GC-MS), as well as its anti-Leishmania potential, cytotoxicity, and macrophage activation capability as possible antiprotozoal mechanism of action were assessed. Fourteen compounds were identified, which constituted 94.87% of total oil composition. The most abundant components were monoterpenes (80.35%), with ß-myrcene (42.46%), α-myrcene (37.23%), and caryophyllene (4.28%) as the major constituents. The MuEO inhibited the growth of promastigotes (IC50 205 ± 13.4 µg mL-1), axenic amastigotes (IC50 104.5 ± 11.82 µg mL-1) and decreased percentage of macrophage infection and number of amastigotes per macrophage (IC50 of 44.5 ± 4.37 µg⋅mL-1), suggesting significant anti-Leishmania activity. The cytotoxicity of MuEO was assessed by MTT test in Balb/c murine macrophages and by human erythrocytes lysis assay and low cytotoxicity for these cells was observed. The CC50 value against macrophages were 550 ± 29.21 µg mL-1, while cytotoxicity for erythrocytes was around 20% at the highest concentration assessed, with HC50 > 800 µg mL-1. While MuEO-induced anti-Leishmania activity is not mediated by increases in both lysosomal activity and nitric oxide production in macrophages, the results suggest the antiamastigote activity is associated with an immunomodulatory activity of macrophages due to an increase of phagocytic capability induced by MuEO. Thus, MuEO presented significant activity against Leishmania amazonensis, probably modulating the activation of macrophages, with low cytotoxicity to murine macrophages and human erythrocytes.


Assuntos
Anacardiaceae/química , Antiprotozoários/farmacologia , Leishmania mexicana/efeitos dos fármacos , Óleos Voláteis/farmacologia , Monoterpenos Acíclicos , Animais , Antiprotozoários/química , Células Cultivadas , Eritrócitos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Hemólise , Humanos , Concentração Inibidora 50 , Lisossomos/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Monoterpenos/análise , Monoterpenos/farmacologia , Óxido Nítrico/metabolismo , Óleos Voláteis/química , Fagocitose , Folhas de Planta/química
9.
Nanoscale ; 8(46): 19390-19401, 2016 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-27847941

RESUMO

Physical forces mediated by cell-cell adhesion molecules, as cadherins, play a crucial role in preserving normal tissue architecture. Accordingly, altered cadherins' expression has been documented as a common event during cancer progression. However, in most studies, no data exist linking pro-tumorigenic signaling and variations in the mechanical balance mediated by adhesive forces. In breast cancer, P-cadherin overexpression increases in vivo tumorigenic ability, as well as in vitro cell invasion, by activating Src family kinase (SFK) signalling. However, it is not known how P-cadherin and SFK activation impact cell-cell biomechanical properties. In the present work, using atomic force microscopy (AFM) images, cell stiffness and cell-cell adhesion measurements, and undirected graph analysis based on microscopic images, we have demonstrated that P-cadherin overexpression promotes significant alterations in cell's morphology, by decreasing cellular height and increasing its area. It also affects biomechanical properties, by decreasing cell-cell adhesion and cell stiffness. Furthermore, cellular network analysis showed alterations in intercellular organization, which is associated with cell-cell adhesion dysfunction, destabilization of an E-cadherin/p120ctn membrane complex and increased cell invasion. Remarkably, inhibition of SFK signaling, using dasatinib, reverted the pathogenic P-cadherin induced effects by increasing cell's height, cell-cell adhesion and cell stiffness, and generating more compact epithelial aggregates, as quantified by intercellular network analysis. In conclusion, P-cadherin/SFK signalling induces topological, morphological and biomechanical cell-cell alterations, which are associated with more invasive breast cancer cells. These effects could be further reverted by dasatinib treatment, demonstrating the applicability of AFM and cell network diagrams for measuring the epithelial biomechanical properties and structural organization.


Assuntos
Caderinas/metabolismo , Mecanotransdução Celular , Microscopia de Força Atômica , Quinases da Família src/metabolismo , Neoplasias da Mama , Adesão Celular , Linhagem Celular Tumoral , Humanos , Células MCF-7
10.
Neurogastroenterol Motil ; 28(11): 1632-1640, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27196538

RESUMO

BACKGROUND: Among the different mechanisms involved in irritable bowel syndrome (IBS) physiopathology, visceral hypersensitivity seems to play a key role. It involves sensitization of the colonic primary afferent fibers, especially through an overexpression of ion channels. The aims of this translational study were to investigate the colonic expression of Cav 3.2 calcium channels and their involvement in an animal model of colonic hypersensitivity, and to assess their expression in the colonic mucosa of symptomatic IBS patients. METHODS: This bench-to-bed study combined a preclinical experimental study on mice and a case-control clinical study. Preclinical studies were performed on wild-type and Cav 3.2-KO mice. Colonic sensitivity and Cav 3.2 expression were studied after a low-dose treatment of dextran sodium sulfate (DSS 0.5%). Regarding the clinical study, colonic biopsies were performed in 14 IBS patients and 16 controls during a colonoscopy to analyze the mucosal Cav 3.2 expression. KEY RESULTS: Wild-type, but not Cav 3.2-KO, mice developed visceral hypersensitivity without colonic inflammation, after 0.5% DSS treatment. A significant increase of Cav 3.2 mRNA (p = 0.04) was found in the colon of low-dose DSS-treated wild-type (WT) mice compared to their controls. In human colonic biopsies, the Cav 3.2 mRNA level was significantly higher in the IBS group compared to the control group (p = 0.01). The immunofluorescence staining revealed their protein expression in colonic mucosa, particularly in nerve fibers. CONCLUSIONS & INFERENCES: This translational study supports the involvement of the calcium channels Cav 3.2 in abdominal pain, as observed in IBS patients. It opens new therapeutic perspectives based on molecules specifically blocking these channels.


Assuntos
Canais de Cálcio Tipo T/biossíntese , Colo/metabolismo , Modelos Animais de Doenças , Síndrome do Intestino Irritável/metabolismo , Dor Visceral/metabolismo , Animais , Canais de Cálcio Tipo T/genética , Colo/patologia , Feminino , Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Síndrome do Intestino Irritável/genética , Síndrome do Intestino Irritável/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Dor Visceral/genética , Dor Visceral/patologia
11.
Colloids Surf B Biointerfaces ; 143: 177-185, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27003468

RESUMO

Exploring novel applications for approved excipients with a history of safe use in therapeutics is a smart strategy to obtain improved pharmaceutical products. The present study aimed at developing a novel starch-based nanoparticulate carrier system (StNC) for topical delivery of lipophilic bioactive molecules. The role of the different factors that affect the particle size distribution and zeta potential of StNC prepared by the emulsification-solvent evaporation method was assessed using a quality by design approach. An optimal formulation was selected and fully characterized in terms of molecular interactions (DSC and FTIR), morphology (TEM and AFM), as well as in vitro and in vivo biological properties, including biological sensitivity/irritation studies performed in human volunteers. Results show the surfactant and lipid contents play a major role in StNC particle size distribution. In addition, all tested formulations presented a zeta potential of ca. +33.6±6.7 mV, indicating a good physical stability, while revealing an excellent compromise between stability, safety and cosmeticity, evidencing that StNC are suitable nanocarriers for topical use. Finally, the design planning methodology has clearly shown its usefulness for optimizing the formulation, being also crucial for the understanding of StNC formation process. The StNC proved to be a promising formulation strategy and a potential nanocarrier for topical lipophilic bioactive molecules.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Nanocápsulas/administração & dosagem , Amido/química , Administração Tópica , Varredura Diferencial de Calorimetria , Linhagem Celular , Portadores de Fármacos/química , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Lipídeos/química , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Tamanho da Partícula , Testes do Emplastro/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química
12.
Sci Rep ; 6: 19399, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26775847

RESUMO

Visceral pain and intestinal dysbiosis are associated with Irritable Bowel Syndrome (IBS), a common functional gastrointestinal disorder without available efficient therapies. In this study, a decrease of Faecalibacterium prausnitzii presence has been observed in an IBS-like rodent model induced by a neonatal maternal separation (NMS) stress. Moreover, it was investigated whether F. prausnitzii may have an impact on colonic sensitivity. The A2-165 reference strain, but not its supernatant, significantly decreased colonic hypersensitivity induced by either NMS in mice or partial restraint stress in rats. This effect was associated with a reinforcement of intestinal epithelial barrier. Thus, F. prausnitzii exhibits anti-nociceptive properties, indicating its potential to treat abdominal pain in IBS patients.


Assuntos
Faecalibacterium prausnitzii/fisiologia , Mucosa Intestinal , Síndrome do Intestino Irritável/etiologia , Animais , Colo/imunologia , Colo/metabolismo , Colo/microbiologia , Modelos Animais de Doenças , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/microbiologia , Masculino , Privação Materna , Camundongos , Permeabilidade , Estresse Fisiológico
13.
Genet Mol Res ; 14(3): 10139-44, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26345950

RESUMO

The purpose of the present study was to functionally evaluate the influence of superoxide radical-generating compounds on the heterologous induction of a predicted promoter region of open reading frames for paraquat-inducible genes (pqi genes) revealed during genome annotation analyses of the Chromobacterium violaceum bacterium. A 388-bp fragment corresponding to a pqi gene promoter of C. violaceum was amplified using specific primers and cloned into a conjugative vector containing the Escherichia coli lacZ gene without a promoter. Assessments of the expression of the ß-galactosidase enzyme were performed in the presence of menadione (MEN) and phenazine methosulfate (PMS) compounds at different final concentrations to evaluate the heterologous activation of the predicted promoter region of interest in C. violaceum induced by these substrates. Under these experimental conditions, the MEN reagent promoted highly significant increases in the expression of the ß-galactosidase enzyme modulated by activating the promoter region of the pqi genes at all concentrations tested. On the other hand, significantly higher levels in the expression of the ß-galactosidase enzyme were detected exclusively in the presence of the PMS reagent at a final concentration of 50 µg/mL. The findings described in the present study demonstrate that superoxide radical-generating compounds can activate a predicted promoter DNA motif for pqi genes of the C. violaceum bacterium in a dose-dependent manner.


Assuntos
Chromobacterium/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Genes Bacterianos , Paraquat/toxicidade , Regiões Promotoras Genéticas , Superóxidos/metabolismo , Chromobacterium/efeitos dos fármacos , beta-Galactosidase/metabolismo
15.
Mucosal Immunol ; 5(3): 288-98, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22318495

RESUMO

Bacterial flagellin is a dominant innate immune activator of the intestine. Therefore, we examined the role of the intracellular flagellin receptor, NLRC4, in protecting the gut and/or driving inflammation. In accordance with NLRC4 acting through transcription-independent pathways, loss of NLRC4 did not reduce the rapid robust changes in intestinal gene expression induced by flagellin administration. Loss of NLRC4 did not alter basal intestinal homeostasis nor predispose mice to development of colitis upon administration of an anti-interleukin (IL)-10R monoclonal antibody. However, epithelial injury induced by dextran sulfate sodium in mice lacking NLRC4 resulted in a more severe disease, indicating a role for NLRC4 in protecting the gut. Moreover, loss of NLRC4 resulted in increased mortality in response to flagellate, but not aflagellate Salmonella infection. Thus, despite not being involved in rapid intestinal gene remodeling upon detection of flagellin, NLRC4-mediated inflammasome activation results in production of IL-1ß and IL-18, two cytokines that protect mice from mucosal and systemic challenges.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Colite/imunologia , Flagelina/metabolismo , Mucosa Intestinal/imunologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/imunologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/imunologia , Células Cultivadas , Colite/induzido quimicamente , Citocinas/genética , Citocinas/metabolismo , Sulfato de Dextrana/administração & dosagem , Modelos Animais de Doenças , Flagelina/genética , Flagelina/imunologia , Humanos , Imunidade Inata/genética , Camundongos , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/imunologia
16.
Int J Oral Maxillofac Surg ; 40(4): 353-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21208782

RESUMO

This prospective longitudinal study assessed the 3D soft tissue changes following mandibular advancement surgery. Cranial base registration was performed for superimposition of virtual models built from cone beam computed tomography (CBCT) volumes. Displacements at the soft and hard tissue chin (n = 20), lower incisors and lower lip (n = 21) were computed for presurgery to splint removal (4-6-week surgical outcome), presurgery to 1 year postsurgery (1-year surgical outcome), and splint removal to 1 year postsurgery (postsurgical adaptation). Qualitative evaluations of color maps illustrated the surgical changes and postsurgical adaptations, but only the lower lip showed statistically significant postsurgical adaptations. Soft and hard tissue chin changes were significantly correlated for each of the intervals evaluated: presurgery to splint removal (r = 0.92), presurgery to 1 year postsurgery (r = 0.86), and splint removal to 1 year postsurgery (r = 0.77). A statistically significant correlation between lower incisor and lower lip was found only between presurgery and 1 year postsurgery (r = 0.55). At 1 year after surgery, 31% of the lower lip changes were explained by changes in the lower incisor position while 73% of the soft tissue chin changes were explained by the hard chin. This study suggests that 3D soft tissue response to mandibular advancement surgery is markedly variable.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Face/anatomia & histologia , Imageamento Tridimensional , Má Oclusão Classe II de Angle/cirurgia , Avanço Mandibular , Adaptação Fisiológica , Adulto , Cefalometria/métodos , Queixo/anatomia & histologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Incisivo/anatomia & histologia , Lábio/anatomia & histologia , Masculino , Estudos Prospectivos , Base do Crânio/anatomia & histologia , Técnica de Subtração , Resultado do Tratamento , Interface Usuário-Computador , Adulto Jovem
17.
Mucosal Immunol ; 4(1): 102-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20844479

RESUMO

Toll-like receptor-5 (TLR5)-mediated detection of flagellin induces nuclear factor (NF)-κB-mediated transcription of host defense gene expression, whereas recognition of intracellular flagellin by interleukin (IL)-1-converting enzyme protease-activation factor (IPAF) results in maturation/secretion of the inflammasome cytokine IL-1ß. The potent effects of IL-1ß are counter-regulated by secretory IL-1 receptor antagonist (sIL-1Ra). We studied the roles of flagellin receptors in regulating the expression of IL-1ß and sIL-1Ra and their subsequent roles in inflammation. Flagellin induced sIL-1Ra in intestinal epithelia and macrophages in a dose- and time-dependent manner, whereas IL-1ß was only induced in macrophages. In vivo, flagellin-induced sIL-1Ra, but not IL-1ß, was absolutely dependent upon TLR5 expressed on non-hemopioetic cells. Thus, loss of TLR5 increased the IL-1ß/sIL-1Ra ratio on flagellin treatment, which correlated with increased inflammatory pathology in response to this product. Furthermore, the flagellin/TLR5 interaction was important for the induction of sIL-1Ra and limiting inflammatory pathology on Salmonella infection. Finally, reduced sIL-1Ra levels in TLR5KO mice correlated with spontaneous colitis. Taken together, we demonstrate that intestinal epithelia, despite not expressing IL-1ß, secrete sIL-1Ra in a TLR5-dependent manner suggesting that loss of TLR5 may promote inflammation by increasing IL-1ß activity. Thus, optimizing the balance between inflammasome cytokines and their endogenous inhibitors might prove a useful strategy to treat inflammatory disorders.


Assuntos
Flagelina/imunologia , Inflamação/imunologia , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-1beta/genética , Receptor 5 Toll-Like/imunologia , Animais , Caspase 1/metabolismo , Linhagem Celular , Colite/imunologia , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Regulação da Expressão Gênica , Inflamassomos , Proteína Antagonista do Receptor de Interleucina 1/genética , Interleucina-1beta/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infecções por Salmonella/imunologia , Receptor 5 Toll-Like/metabolismo
18.
Rev. bras. plantas med ; 13(2): 146-150, 2011. ilus
Artigo em Português | LILACS | ID: lil-596387

RESUMO

O presente trabalho teve por objetivo analisar a ação antiinflamatória do gel da Babosa a 2 por cento (Aloe barbadensis Mill.) associado ao Ultrassom pulsátil no modelo de edema de pata. Foram utilizados 25 ratos Wistar, (200-250 g), divididos em 5 grupos de 5 animais cada. Grupo1 (controle): ratos tratados com solução salina a 0,9 por cento; Grupo 2: ratos tratados topicamente com gel de A. barbadensis Mill. a 2 por cento; Grupo 3: animais tratados com Ultrassom; Grupo 4: ratos tratados com gel de A. barbadensis Mill. a 2 por cento associado ao Ultrassom; Grupo 5 (controle positivo): ratos tratados com Indometacina na dose de 5 mg Kg-1. Os animais dos grupos 1 e 5 receberam os respectivos tratamentos por via intra-peritoneal 30 minutos antes da injeção intra-plantar de carragenina e os grupos 2, 3 e 4 foram tratados por aplicação tópica de gel de A. barbadensis Mill. a 2 por cento, Ultrassom pulsátil e gel de A. barbadensis Mill. associado ao Ultrassom respectivamente 15 minutos após a indução do edema. Os animais do grupo 04 demonstraram redução significativa do edema quando comparados ao grupo controle, ao mesmo tempo, que se mostrou comparável à indometacina. Observou-se que o gel de aloe associado à fonoforose é capaz reduzir a formação do edema de pata em ratos.


This work aimed to evaluate the anti-inflammatory action of 2 percent aloe (Aloe barbadensis Mill.) gel combined with pulsed ultrasound in the paw edema model. Twenty-five Wistar rats (200-250 g) were divided into 5 groups of 5 animals each. Group1 (control): rats treated with 0.9 percent saline; Group 2: rats topically treated with 2 percent aloe gel; Group 3: rats treated with ultrasound; Group 4: rats treated with 2 percent aloe gel combined with ultrasound; Group 5 (positive control): rats treated with indomethacin at 5 mg Kg-1. Animals of groups 1 and 5 were intraperitoneally treated 30 min before intraplantar carrageenan injection and groups 2, 3 and 4 were treated by topical application of 2 percent aloe gel, pulsed ultrasound and aloe gel combined with ultrasound, respectively, 15 min after edema induction. Animals of group 4 had a significant reduction in edema relative to controls and showed to be comparable to indomethacin. Aloe gel combined with phonophoresis is capable of reducing paw edema formation in rats.


Assuntos
Animais , Ratos , Anti-Inflamatórios , Aloe , Protocolos Clínicos , Géis/uso terapêutico , Fonoforese , Terapêutica/estatística & dados numéricos , Plantas Medicinais , Tendinopatia/tratamento farmacológico , Tendinopatia/terapia , Tendinopatia
19.
Mucosal Immunol ; 3(6): 622-32, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20664578

RESUMO

Rotavirus (RV), a leading cause of severe diarrhea, primarily infects intestinal epithelial cells (IECs) causing self-limiting illness. To better understand innate immunity to RV, we sought to define the extent to which IEC activation of anti-viral responses required viral replication or could be recapitulated by inactivated RV or its components. Using model human intestinal epithelia, we observed that RV-induced activation of signaling events and gene expression typically associated with viral infection was largely mimicked by administration of ultraviolet (UV)-inactivated RV. Use of anti-interferon (IFN) neutralizing antibodies revealed that such replication-independent anti-viral gene expression required type I IFN signaling. In contrast, RV-induction of nuclear factor-κB-mediated interleukin-8 expression was dependent on viral replication. The anti-viral gene expression induced by UV-RV was not significantly recapitulated by RV RNA or RV virus-like particles although the latter could enter IEC. Together, these results suggest that RV proteins mediate viral entry into epithelial cells leading to intracellular detection of RV RNA that generates an anti-viral response.


Assuntos
Interferon Tipo I/metabolismo , Mucosa Intestinal/metabolismo , NF-kappa B/metabolismo , Infecções por Rotavirus/imunologia , Rotavirus/fisiologia , Anticorpos Bloqueadores/farmacologia , Linhagem Celular , Regulação Viral da Expressão Gênica/imunologia , Humanos , Imunidade Inata , Interferon Tipo I/imunologia , Interleucina-8/biossíntese , Interleucina-8/genética , Interleucina-8/imunologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , NF-kappa B/imunologia , RNA Viral/imunologia , Rotavirus/patogenicidade , Infecções por Rotavirus/virologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Raios Ultravioleta , Vírion/imunologia , Inativação de Vírus , Replicação Viral
20.
J Membr Biol ; 228(2): 89-97, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19294450

RESUMO

Circulating acetylcholine, substrate of membrane acetylcholinesterase (AChE), is known to enhance the band 3 protein degree of phosphorylation. The purpose of this study was to verify whether the band 3 phosphorylation status is associated with a G protein and whether it is an influent factor on AChE enzyme activity. From blood samples of healthy donors, erythrocyte suspensions were prepared and incubated with AChE substrate (acetylcholine) and inhibitor (velnacrine), along with protein tyrosine kinase (PTK) and tyrosine phosphatase (PTP) inhibitors. AChE activity was determined by spectrophotometry and extract samples were analyzed by western blotting using primary antibodies to different G protein subunits. Our results with phosphorylated band 3 (PTP inhibitor) show an increase in erythrocyte AChE (p < 0.0001). A dephosphorylated band 3 state (PTK inhibitor) shows a significant decrease. We identified a potential linkage of protein subunits Galpha(i1/2) and G(beta) with band 3 protein. Galpha(i1/2) and G(beta) may be linked to the band 3 C-terminal site. Galpha(i1/2) is associated with the band 3 N-terminal domain, except for the control and ACh aliquots. G(beta) is associated with both phosphorylated and dephosphorylated band 3 in the presence of velnacrine. We conclude that an erythrocyte G protein with subunits Galpha(i1/2) and G(beta) is associated with band 3. AChE depends on the degree of band 3 phosphorylation and its association with Galpha(i1/2) and G(beta).


Assuntos
Acetilcolinesterase/metabolismo , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Eritrócitos/enzimologia , Eritrócitos/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Western Blotting , Dipeptídeos/farmacologia , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Eritrócitos/efeitos dos fármacos , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Subunidades beta da Proteína de Ligação ao GTP/metabolismo , Humanos , Imunoprecipitação , Masculino , Ligação Proteica , Tacrina/análogos & derivados , Tacrina/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA