pectins and Enterobacteriaceae-Infections

Topics: Animals; Bacteriocins; Bacteriophages; Carbohydrate Metabolism; Culture Media; DNA, Bacterial; Drug Resistance, Microbial; Enterobacteriaceae Infections; Erwinia; Genetic Variation; Glycosides; Humans; Lysogeny; Nitrogen; Pectins; Plant Diseases; Recombination, Genetic; Symbiosis

Topics: Animals; Biodiversity; Butyrates; Cell Proliferation; Citrobacter rodentium; Colitis; Diet; Enterobacteriaceae Infections; Epithelium; Fermentation; Gene Expression Profiling; Gene Expression Regulation; HEK293 Cells; Humans; Mice, Inbred C57BL; Microbiota; Mucin-2; Pectins; Promoter Regions, Genetic; Receptors, G-Protein-Coupled; Regeneration; Stem Cells; Transcription, Genetic; Triglycerides

Pectins have anti-inflammatory properties on intestinal immunity through direct interactions on Toll-like receptors (TLRs) in the small intestine or via stimulating microbiota-dependent effects in the large intestine. Both the degree of methyl-esterification (DM) and the distribution of methyl-esters (degree of blockiness; DB) of pectins contribute to this influence on immunity, but whether and how the DB impacts immunity through microbiota-dependent effects in the large intestine is unknown. Therefore, this study tests pectins that structurally differ in DB in a mouse model with Citrobacter rodentium induced colitis and studies the impact on the intestinal microbiota composition and associated attenuation of inflammation.. Both low and high DB pectins induce a more rich and diverse microbiota composition. These pectins also lower the bacterial load of C. rodentium in cecal digesta. Through these effects, both low and high DB pectins attenuate C. rodentium induced colitis resulting in reduced intestinal damage, reduced numbers of Th1-cells, which are increased in case of C. rodentium induced colitis, and reduced levels of GATA3. Pectins prevent C. rodentium induced colonic inflammation by lowering the C. rodentium load in the caecum independently of the DB.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Cecum; Citrobacter rodentium; Citrus sinensis; Colitis; Cytokines; Enterobacteriaceae Infections; Esters; Female; Gastrointestinal Microbiome; Mice, Inbred C57BL; Pectins; T-Lymphocyte Subsets

Enteric pathogens sense the complex chemistry within the gastrointestinal tract to efficiently compete with the resident microbiota and establish a colonization niche. Here, we show that enterohaemorrhagic Escherichia coli and Citrobacter rodentium, its surrogate in a mouse infection model, sense galacturonic acid to initiate a multi-layered program towards successful mammalian infection. Galacturonic acid utilization as a carbon source aids the initial pathogen expansion. The main source of galacturonic acid is dietary pectin, which is converted to galacturonic acid by the prominent member of the microbiota, Bacteroides thetaiotamicron. This is regulated by the ExuR transcription factor. However, galacturonic acid is also sensed as a signal through ExuR to modulate the expression of the genes encoding a molecular syringe known as a type III secretion system, leading to infectious colitis and inflammation. Galacturonic acid acts as both a nutrient and a signal directing the exquisite microbiota-pathogen relationships within the gastrointestinal tract. This work highlights that differential dietary sugar availability influences the relationship between the microbiota and enteric pathogens, as well as disease outcomes.

Topics: Animals; Bacteroides thetaiotaomicron; Citrobacter rodentium; Diet; Disease Models, Animal; Enterobacteriaceae Infections; Enterohemorrhagic Escherichia coli; Escherichia coli Infections; Female; Gastrointestinal Microbiome; Genes, Bacterial; HeLa Cells; Hexuronic Acids; Host-Pathogen Interactions; Humans; Mice; Mice, Inbred C3H; Mice, Inbred C57BL; Pectins; Virulence

In this study, we demonstrate the enhanced disease resistance and positive immunomodulation of novel pectin isolated from Spirulina maxima (SmP) in zebrafish model. Zebrafish larvae exposed to SmP had significantly (p < 0.05) higher cumulative percent survival (CPS) at 25 (44.0%) and 50 μg/mL (67.0%) against Edwardsiella piscicida compared to the control. However, upon Aeromonas hydrophila challenge, SmP exposed larvae at 50 μg/mL had slightly higher CPS (33.3%) compared to control group (26.7%). SmP supplemented zebrafish exhibited the higher CPS against E. piscicida (93.3%) and A. hydrophila (60.0%) during the early stage of post-infection (<18 hpi). qRT-PCR results demonstrated that exposing (larvae) and feeding (adults) of SmP, drive the modulation of a wide array of immune response genes. In SmP exposed larvae, up-regulation of the antimicrobial enzyme (lyz: 3.5-fold), mucin (muc5.1: 2.84, muc5.2: 2.11 and muc5.3: 2.40-fold), pro-inflammatory cytokines (il1β: 1.79-fold) and anti-oxidants (cat: 2.87 and sod1: 1.82-fold) were identified. In SmP fed adult zebrafish (gut) showed >2-fold induced pro-inflammatory cytokine (il1β) and chemokines (cxcl18b, ccl34a.4 and ccl34b.4). Overall results confirmed the positive modulation of innate immune responses in larval stage and it could be the main reason for developing disease resistance against E. piscicida and A. hydrophila. Thus, non-toxic, natural and biodegradable SmP could be considered as the potential immunomodulatory agent for sustainable aquaculture.

Topics: Aeromonas hydrophila; Animal Feed; Animals; Bacterial Proteins; Cyanobacteria; Diet; Dietary Proteins; Dietary Supplements; Disease Resistance; Edwardsiella; Enterobacteriaceae Infections; Fish Diseases; Gram-Negative Bacterial Infections; Immunity, Innate; Pectins; Zebrafish