Project description:Obesity is a chronic, complex and multifactorial disease that has reached pandemia levels and is becoming a serious health problem. Intestinal microbiota is considered a main factor that affects body weight and fat mass, which points toward a critical role in the development of obesity. In this sense, probiotic bacteria might modulate the intestinal microbiota and the mucosal-associated lymphoid tissue. The aim of this study was to investigate the effects of L. paracasei, L. rhamnosus and B. breve feeding on the intestinal mucosa gene expression in a genetic animal model of obesity. We used microarrays to investigate the global gene expression on intestinal mucosa after the treatment with probiotic strains.
Project description:Intestinal microbiota colonization is important for intestinal development and health of preterm infants, especially those with extremely low birth weight. Recent studies indicated for a dynamic crosstalk between that gut microbiota and DNA methylome of host intestinal cells. Thereby, we sought to determine the epigenomic and metagenomic consequences of suppression of microbiota colonization in the intestine of preterm neonates to gain insights into biological pathways that shape the interface between the gut microbiota and the preterm intestinal cells. We examined 14 preterm piglets by comparing the conventional preterm neonates with those ones treated with oral antibiotics for genome wide DNA methylation and 16S rDNA microbiome. Our results demonstrated an extensive genome-wide DNA methylation changes in response to the suppression of intestinal microbe colonization, especially genes involved in neonatal immune response signaling and glycol-metabolism pathways were identified. Our study highlights several key genes that might predispose preterm neonates to NEC risk due to their key roles involved in the immune-metabolic networks. Our study not only provided rich omic-data to interpret molecular program in relation with microbiota-associated methylome-proteome network changes, but also confer clinical usage of key gene markers for potential early diagnostics of NEC of preterm neonates.
Project description:Inappropriate cross talk between mammals and their gut microbiota may trigger intestinal inflammation and drive extra-intestinal immune-mediated diseases. Studies with germ-free or gnotobiotic animals represent the gold standard for research on bacterial-host interaction but they are not readily accessible to the wide scientific community. We aimed at refining a protocol that in a robust manner would deplete murine intestinal microbiota and prove to have significant biologic validity. Previously published protocols for depleting mice of their intestinal microbiota by administering broad-spectrum antibiotics in drinking water were difficult to reproduce. We show that twice daily delivery of antibiotics by gavage depleted mice of their cultivable fecal microbiota and reduced the fecal bacterial DNA load by approximately 400 fold while ensuring the animals’ health. Mice subjected to the protocol for 17 days displayed enlarged ceca, reduced Peyer’s patches and small spleens. Antibiotic treatment significantly reduced the expression of antimicrobial factors and altered the expression of 517 genes in total in the colonic epithelium. Genes involved in cell cycle were significantly altered concomitant with reduced epithelial proliferative activity in situ assessed by Ki-67 expression, suggesting that commensal microbiota drives cellular proliferation in colonic epithelium. We present a robust protocol for depleting mice of their cultivatable intestinal microbiota with antibiotics by gavage and show that the biological effect of this depletion is phenotypic characteristics and epithelial gene expression profile similar to those of germ-free mice. Comparison of genome-wide gene expression of colon intestinal epithelial cells from mice subjected to microbiota depletion protocol against to control mice.
Project description:Diet influences the composition and diversity of mucosa-associated microbiota along the longitudinal axis of the pig gastrointestinal tract.
Project description:We developed a non-invasive ex vivo HT29 cell-based minimal model to fingerprint the mucosa-associated microbiota fraction in humans. HT29 cell-associated fractions were characterized by the universal phylogenetic array platform HTF-Microbi.Array, both in presence or in absence of a TNF-M-NM-1-mediated pro-inflammatory stimulus. A high taxonomical level fingerprint profiling of the mucosa-associated microbiota was performed on a group of 12 breast-fed infants and 6 adults (used as controls). Relative abundance of the bacterial species was assessed by using a so-called HTF-Microbi.Array, based on a ligation detection reaction (LDR) - Univerasal array (UA) assay, capable of correctly identify up to 31 intestinal bacterial groups, covering up to 95% of the human gut microbiota
Project description:Background: Restitution of the surface epithelium is a critical healing process early after ischaemic injury of the gut mucosa. Repeated episodes of intestinal ischaemia occur in many critically ill patients. This study evaluates the resistance of postischaemic restituted intestinal mucosa to a further ischaemic insult. Methods: The superior mesenteric artery (SMA) in pigs was cross-clamped for 1 hour, reperfused for 4 hours, cross-clamped once again for 1 hour, and finally reperfused for 3 hours. Intestinal injury was evaluated with morphometry. Intestinal permeability (from blood to lumen was assessed by transport of fluorescein isothiocyanate dextran (FD-4). Microarray and QRT-PCR analysis were performed.
Project description:Inappropriate cross talk between mammals and their gut microbiota may trigger intestinal inflammation and drive extra-intestinal immune-mediated diseases. Studies with germ-free or gnotobiotic animals represent the gold standard for research on bacterial-host interaction but they are not readily accessible to the wide scientific community. We aimed at refining a protocol that in a robust manner would deplete murine intestinal microbiota and prove to have significant biologic validity. Previously published protocols for depleting mice of their intestinal microbiota by administering broad-spectrum antibiotics in drinking water were difficult to reproduce. We show that twice daily delivery of antibiotics by gavage depleted mice of their cultivable fecal microbiota and reduced the fecal bacterial DNA load by approximately 400 fold while ensuring the animals’ health. Mice subjected to the protocol for 17 days displayed enlarged ceca, reduced Peyer’s patches and small spleens. Antibiotic treatment significantly reduced the expression of antimicrobial factors and altered the expression of 517 genes in total in the colonic epithelium. Genes involved in cell cycle were significantly altered concomitant with reduced epithelial proliferative activity in situ assessed by Ki-67 expression, suggesting that commensal microbiota drives cellular proliferation in colonic epithelium. We present a robust protocol for depleting mice of their cultivatable intestinal microbiota with antibiotics by gavage and show that the biological effect of this depletion is phenotypic characteristics and epithelial gene expression profile similar to those of germ-free mice.