RESUMEN
The gut microbiota plays a significant role in human health; however, the complex relationship between gut microbial communities and host health is still to be thoroughly studied and understood. Microbes in the distal gut contribute to host health through the biosynthesis of vitamins and essential amino acids and the generation of important metabolic by-products from dietary components that are left undigested by the small intestine. Aged citrus peel (Chenpi) is used in traditional Chinese medicine to lower cholesterol, promote weight loss and treat various gastrointestinal symptoms. This study investigated how the microbial community changes during treatment with Chenpi using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME). Two preparations of Chenpi extract were tested: Chenpi suspended in oil only and Chenpi in a viscoelastic emulsion. Short-chain fatty acids (SCFAs) were measured during treatment to monitor changes in the microbial community of the colon presenting a decrease in production for acetic, propionic and butyric acid (ANOVA (P < 0.001) during the 15 days of treatment. 16S rRNA sequencing of microbial samples showed a clear difference between the two treatments at the different sampling times (ANOSIM P < 0.003; ADOSIM P < 0.002 [R2 = 69%]). Beta diversity analysis by PcoA showed differences between the two Chenpi formulations for treatment day 6. These differences were no longer detectable as soon as the Chenpi treatment was stopped, showing a reversible effect of Chenpi on the human microbiome. 16S rRNA sequencing of microbial samples from the descending colon showed an increase in Firmicutes for the treatment with the viscoelastic emulsion. At the genus level, Roseburia, Blautia, Subdoligranulum and Eubacterium increased in numbers during the viscoelastic emulsion treatment. This study sheds light on the anti-obesity effect of a polymethoxyflavone (PMFs)-enriched Chenpi extract and creates a foundation for the identification of 'obesity-prevention' biomarkers in the gut microbiota.
Asunto(s)
Medicamentos Herbarios Chinos , Microbiota , Anciano , Clostridiales , Emulsiones , Humanos , Obesidad , ARN Ribosómico 16S/genéticaRESUMEN
The interferon-gamma (IFN-γ) test measures cell mediated immune response (CMI) during the early stages of tuberculosis infection. Although Bovine Tuberculosis (BT) spread in feral pigs is widely documented in literature, the effectiveness of IFN-γ in this species has been only recently reported. One of the major obstacle of this assay is that whole blood samples should be stimulated with purified protein derivative (PPD) cocktail within 8 h from the blood sampling. This study set up a defined broth culture in which lymphocytes, the cell population predominantly responsible for IFN-γ production, are maintained in a steady-state and their vitality is preserved. The IFN-γ production measured from the samples added with the maintenance medium and stored at 4 °C was similar to the enzyme-linked immunosorbent assay (ELISA) optical density values obtained from the same assay performed within 8 h from sampling.
Asunto(s)
Ensayos de Liberación de Interferón gamma/veterinaria , Interferón gamma/inmunología , Linfocitos/inmunología , Mycobacterium bovis/inmunología , Enfermedades de los Porcinos/diagnóstico , Tuberculosis/veterinaria , Animales , Técnicas de Cultivo de Célula/veterinaria , Células Cultivadas , Interacciones Huésped-Patógeno , Interferón gamma/sangre , Linfocitos/metabolismo , Linfocitos/microbiología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Porcinos , Enfermedades de los Porcinos/sangre , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/microbiología , Factores de Tiempo , Tuberculosis/diagnóstico , Tuberculosis/inmunología , Tuberculosis/microbiologíaRESUMEN
SslE, the Secreted and surface-associated lipoprotein from Escherichia coli, has recently been associated to the M60-like extracellular zinc-metalloprotease sub-family which is implicated in glycan recognition and processing. SslE can be divided into two main variants and we recently proposed it as a potential vaccine candidate. By applying a number of in vitro bioassays and comparing wild type, knockout mutant and complemented strains, we have now demonstrated that SslE specifically contributes to degradation of mucin substrates, typically present in the intestine and bladder. Mutation of the zinc metallopeptidase motif of SslE dramatically impaired E. coli mucinase activity, confirming the specificity of the phenotype observed. Moreover, antibodies raised against variant I SslE, cloned from strain IHE3034 (SslEIHE3034), are able to inhibit translocation of E. coli strains expressing different variants through a mucin-based matrix, suggesting that SslE induces cross-reactive functional antibodies that affect the metallopeptidase activity. To test this hypothesis, we used well-established animal models and demonstrated that immunization with SslEIHE3034 significantly reduced gut, kidney and spleen colonization by strains producing variant II SslE and belonging to different pathotypes. Taken together, these data strongly support the importance of SslE in E. coli colonization of mucosal surfaces and reinforce the use of this antigen as a component of a broadly protective vaccine against pathogenic E. coli species.
Asunto(s)
Anticuerpos Antibacterianos/farmacología , Formación de Anticuerpos , Infecciones por Escherichia coli , Proteínas de Escherichia coli/inmunología , Polisacárido Liasas/antagonistas & inhibidores , Factores de Virulencia/inmunología , Animales , Animales no Consanguíneos , Anticuerpos Antibacterianos/metabolismo , Células Cultivadas , Escherichia coli Enteropatógena/crecimiento & desarrollo , Escherichia coli Enteropatógena/inmunología , Escherichia coli Enteropatógena/metabolismo , Activación Enzimática/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/inmunología , Escherichia coli/metabolismo , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/antagonistas & inhibidores , Proteínas de Escherichia coli/metabolismo , Femenino , Intestinos/microbiología , Ratones , Ratones Endogámicos CBA , Polisacárido Liasas/inmunología , Polisacárido Liasas/metabolismo , Factores de Virulencia/antagonistas & inhibidores , Factores de Virulencia/metabolismoRESUMEN
The antiviral activities of type I IFNs have long been established. However, comparatively little is known of their role in defenses against nonviral pathogens. We examined here the effects of type I IFNs on host resistance against the model pathogenic yeast Cryptococcus neoformans. After intratracheal or i.v. challenge with this fungus, most mice lacking either the IFN-alpha/beta receptor (IFN-alpha/betaR) or IFN-beta died from unrestrained pneumonia and encephalitis, while all wild-type controls survived. The pulmonary immune response of IFN-alpha/betaR-/- mice was characterized by increased expression of IL-4, IL-13, and IL-10, decreased expression of TNF-alpha, IFN-gamma, inducible NO synthetase, and CXCL10, and similar levels of IL-12 mRNA, compared with wild-type controls. Histopathological analysis showed eosinophilic infiltrates in the lungs of IFN-alpha/betaR-/- mice, although this change was less extensive than that observed in similarly infected IFN-gammaR-deficient animals. Type I IFN responses could not be detected in the lung after intratracheal challenge. However, small, but statistically significant, elevations in IFN-beta levels were measured in the supernatants of bone marrow-derived macrophages or dendritic cells infected with C. neoformans. Our data demonstrate that type I IFN signaling is required for polarization of cytokine responses toward a protective type I pattern during cryptococcal infection.