A5106466032- Gut microbiota and health
- Gastrointestinal motility and disorders
- Celiac Disease Research and Management
- Ion channel regulation and function
- Neuropeptides and Animal Physiology
- Microscopic Colitis
- Gastroesophageal reflux and treatments
- Clostridium difficile and Clostridium perfringens research
- Neuroscience of respiration and sleep
- Neuroendocrine regulation and behavior
- Helicobacter pylori-related gastroenterology studies
- Inflammatory Bowel Disease
- Dietary Effects on Health
- Neuroscience and Neuropharmacology Research
- Probiotics and Fermented Foods
- Stress Responses and Cortisol
- Microbial Metabolites in Food Biotechnology
- Digestive system and related health
- Eosinophilic Esophagitis
- Cardiac electrophysiology and arrhythmias
- Receptor Mechanisms and Signaling
- Diet and metabolism studies
- Infant Health and Development
- Adipokines, Inflammation, and Metabolic Diseases
- Ion Transport and Channel Regulation
Population Health Research Institute
2014-2023
McMaster University
2013-2023
McMaster University Medical Centre
1986-2011
Health Sciences Centre
2001-2011
Indiana University School of Medicine
2009
Indiana University – Purdue University Indianapolis
2009
University of Bristol
1997-1999
<h3>Background:</h3> We previously showed that neonatal maternal separation (MS) of rat pups causes immediate and long-term changes in intestinal physiology. <h3>Aim:</h3> To examine if administration probiotics affects MS-induced gut dysfunction. <h3>Methods:</h3> MS were separated from the dam for 3 h/day days 4 to 19; non-separated (NS) served as controls. Twice per day during period, 10<sup>8</sup> probiotic organisms (two strains <i>Lactobacillus</i> species) administered NS pups;...
Fecal microbiota transplants from patients with irritable bowel syndrome and anxiety alter gut function behavior in germ-free mice.
<b>Background and aim:</b> Chronic psychological stress, including water avoidance stress (WAS), induces intestinal mucosal barrier dysfunction impairs defences against luminal bacteria. The aim of this study was to determine the ability a defined probiotic regimen prevent WAS induced pathophysiology. <b>Methods:</b> Male rats were subjected either or sham for one hour per day 10 consecutive days. Additional animals received seven days <i>Lactobacillus helveticus</i> <i>L rhamnosus</i> in...
The human gut houses one of the most complex and abundant ecosystems composed up to 10(13)-10(14) microorganisms. importance this intestinal microbiota is highlighted when a disruption ecosystem equilibrium appears (a phenomenon called dysbiosis) leading an illness status, such as inflammatory bowel diseases (IBD). Indeed, reduction commensal bacterium Faecalibacterium prausnitzii (one prevalent bacterial species in healthy adults) has been correlated with several diseases, including IBD,...
Metabolism of tryptophan by the gut microbiota into derivatives that activate aryl hydrocarbon receptor (AhR) contributes to intestinal homeostasis. Many chronic inflammatory conditions, including celiac disease involving a loss tolerance dietary gluten, are influenced cues from microbiota. We investigated whether AhR ligand production could influence gluten immunopathology in nonobese diabetic (NOD) mice expressing DQ8, susceptibility gene. NOD/DQ8 mice, exposed or not were subjected three...
Abstract The intestinal barrier encompasses structural, permeability and immune aspects of the gut mucosa that, when disrupted, may contribute to chronic inflammation. Although gnotobiotic studies have demonstrated effects microbiota on mucosal systemic immunity, as well architecture innate characteristics, its impact function remains unclear. We compared germ-free conventional mice, mice colonized with human fecal that were followed for 21 days post-colonization. Colonic structure was...
The intestinal microbiota regulates key host functions. It is unknown whether modulation of the can affect a genetically determined phenotype. Polymorphisms in Nucleotide oligomerization domain (Nod)-like receptor family confer genetic risk for inflammatory bowel disease (IBD). We investigated and probiotic strain Bifidobacterium breve NCC2950 barrier function responses to injury Nod1(-/-); Nod2(-/-) mice.Specific pathogen-free (SPF) mice gnotobiotically derived with altered Schaedler flora...
Alterations in the intestinal microbiota, characterized by depletion of anti-inflammatory bacteria, such as Firmicutes, patients with ulcerative colitis (UC) have prompted interest microbiota-modulating strategies for this condition. The aim study was to evaluate role fecal and synthetic human microbial ecosystems, low or enriched on susceptibility host immune responses.The microbiota selected healthy UC donors culture method 16S rRNA-based sequencing. Germ-free mice were colonized a...
Neonatal maternal separation (MS) predisposes adult rats to develop stress-induced mucosal barrier dysfunction/visceral hypersensitivity and rat pups colonic epithelial dysfunction. Our aim was examine if enhanced permeability in such resulted from abnormal regulation by enteric nerves. Pups were separated the dam for 3 h/day (days 4-20); nonseparated (NS) served as controls. On day 20, tissues removed mounted Ussing chambers. Horseradish peroxidase (HRP) flux used measure macromolecular...
Chronic psychological stress causes intestinal barrier dysfunction and impairs host defense mechanisms mediated by corticotrophin-releasing factor (CRF) mast cells; however, the exact pathways involved are unclear. Here we investigated effect of chronic CRF administration on colonic permeability ion transport functions in rats role cells maintaining abnormalities. was delivered over 12 days via osmotic minipumps implanted subcutaneously wild-type (+/+) cell-deficient (Ws/Ws) rats. Colonic...
ABSTRACT The intestinal microbiota is a key determinant of gut homeostasis, which achieved, in part, through regulation antimicrobial peptide secretion. aim this study was to determine the efficiency by members induce REGIII and elucidate underlying pathways. We showed that germfree mice have low levels REGIII-γ their ileum colon compared with different backgrounds. Colonization diversity (altered Schaedler flora) did not expression as effectively complex community (specific pathogen free)....
Crohn's disease (CD), characterized by discontinuous intestinal injury and inflammation, has been associated with changes in luminal microbial composition impaired barrier function. The relationships between visual features of injury, permeability, the mucosa-associated microbiota are unclear. Individuals undergoing routine colonoscopy (controls) patients CD were evaluated clinical parameters confocal laser scanning endomicroscopic (CLE). Patients categorized as either no (CD-NI) or (CD-I)....
Abstract Crohn’s disease is an inflammatory of the gastrointestinal tract characterized by aberrant response to microbial and environmental triggers. This includes altered microbiome dominated Enterobacteriaceae in particular adherent-invasive E. coli (AIEC). Clinical evidence implicates periods psychological stress exacerbation, disturbances gut might contribute pathogenic mechanism. Here we show that stress-exposed mice develop ileal dysbiosis, expansion Enterobacteriaceae. In AIEC...
This study tested the hypothesis that final mediator of nonadrenergic, noncholinergic (NANC) inhibitory junction potentials (ijps) and associated relaxation responses was nitric oxide (NO) or a related substance not vasoactive intestinal polypeptide (VIP). We used opossum esophagus body circular muscle canine intestine muscle. In both these tissues, ijps had reversal near potassium equilibrium potential, (E K ); in were apamin insensitive, but they partially sensitive. N ω -Nitro-L-arginine...
Abstract Celiac disease (CD) is frequently diagnosed in patients with type 1 diabetes (T1D), and T1D can exhibit Abs against tissue transglutaminase, the auto-antigen CD. Thus, gliadin, trigger CD, has been suggested to have a role pathogenesis. The objective of this study was investigate whether gliadin contributes enteropathy insulitis NOD-DQ8 mice, an animal model that does not spontaneously develop T1D. Gliadin-sensitized mice developed moderate enteropathy, intraepithelial...