China
Africa
Explore chapters and articles related to this topic
The Nutrition-Focused History and Physical Examination (NFPE) in Malnutrition
Published in Michael M. Rothkopf, Jennifer C. Johnson, Optimizing Metabolic Status for the Hospitalized Patient, 2023
Michael M. Rothkopf, Jennifer C. Johnson
Secretin also stimulates hepatic bile production. The gallbladder is then stimulated to contract by duodenal cholecystokinin release from enteroendocrine I cells. This sends bile into the duodenum to emulsify dietary fat and enable pancreatic lipase to act upon it. As digestion occurs, the food bolus is degraded and nutrients are absorbed. Peristalsis pushes the food bolus down the bowel until it reaches the ileocecal valve. When the valve opens, the undigested remnants (also called the residual) move into the cecum and start to process into stool. Gut bacteria act on some of this residual to produce short chain fatty acids. The remainder, along with sloughed luminal cells and bacteria, are passed out the rectum.
Nutritional requirements
Published in Judy More, Infant, Child and Adolescent Nutrition, 2021
Soluble fibre (pectin, gums, mucilage extracted from psyllium husk, β-glucan, fructans and some hemicellulose) is resistant to digestion in the small intestine but is partially or totally fermented by colonic bacteria to short-chain fatty acids in the large intestine. These short chain fatty acids provide small amounts of energy and maintain or alter the intestinal microbiota.
Participation of Vagal Sensory Neurons in Putative Satiety Signals from the Upper Gastrointestinal Tract
Published in Sue Ritter, Robert C. Ritter, Charles D. Barnes, Neuroanatomy and Physiology of Abdominal Vagal Afferents, 2020
R.C. Ritter, L. Brenner, D.P. Yox
With regard to chemical stimulation of the intestine, a variety of nutrient- related responses have been observed. Mei51 has reported afferent fibers that increase their firing rate in response to intraluminal oligosaccharides, especially glucose. Likewise, hindbrain neurons that receive afferent vagal projections also respond to intestinal glucose infusion.24 Jeanningros44 has reported intestinal afferents that respond rather selectively to amino acids. Although a few of these units also responded to glucose, they were not responsive to osmotic or mechanical stimuli. Vagal afferents responding to fatty acids have been recorded by Melone.52 The fatty acid response is greater to long-chain than short- chain fatty acids and is not mimicked by other organic acids or mineral acids.
Campylobacter jejuni permeabilizes the host cell membrane by short chain lysophosphatidylethanolamines
Published in Gut Microbes, 2022
Xuefeng Cao, Chris H.A. van de Lest, Liane Z.X. Huang, Jos P.M. van Putten, Marc M.S.M. Wösten
Interestingly, the cytotoxicity of C. jejuni membranes and purified lysoPE was also observed for epithelial cells as evident from the strong PldA dependent increase of LDH release and the staining of intracellular membranes with WGA in lysoPE-treated cells only (Figure 4b & S2B). Maximum LDH release and intracellular staining were observed after exposure to short chain fatty acid containing lysoPE (Figure 3c). In humans, short-chain fatty acids have been identified as signaling molecules between the gut microbiota and the host, and are regarded as toxic at high concentration.28C. jejuni has been shown to induce LDH release in human neutrophils and dendritic cells (less than 10%), but in epithelial cells the LDH release is relatively low.15,29 We were able to strongly increase the LDH release from the epithelial cells by replacing the tissue culture medium with DPBS during the incubation with C. jejuni (Fig. S3). We noticed that calcium excess in the culture medium reduces the C. jejuni cytotoxicity as has been noted for C. coli PldA.30
Stool multi-omics for the study of host–microbe interactions in inflammatory bowel disease
Published in Gut Microbes, 2022
Consuelo Sauceda, Charlie Bayne, Khadijeh Sudqi, Antonio Gonzalez, Parambir S. Dulai, Rob Knight, David J. Gonzalez, Carlos G. Gonzalez
However, the rise of ever-more powerful -omic technologies has refined our understanding of IBD as a complex and dynamic disease composed of many possible interactions between host and gut microbes.14 Supporting this connection, recent IBD patient profiling efforts suggest that host immune tone heavily influences the gut-microbe composition,13,15 resulting in increased proportions of the phylum Bacteroidetes and decreased proportions of Firmicutes relative to healthy populations.16–19 These findings suggested that dysbiotic microbial composition contributes to IBD.19 Since then, research on host-microbe crosstalk has provided evidence supporting pathologic roles for specific microbes, with effects ranging from barrier disruption to influencing immune cell repertoire. Given its ability to influence microbial growth, dietary intake has also now been implicated as critical to IBD pathology and treatment.20–22 These revelations led to metabolic studies suggesting microbial products such as short-chain fatty acids influence can modulate host immune systems.23 Despite these gains in knowledge, we are only beginning to understand the molecular network of factors influencing IBD heterogeneity, which significantly complicates progress toward precision medicine goals.
Gut Bacteroides species in health and disease
Published in Gut Microbes, 2021
Metabolites secreted by different Bacteroides spp. assist in maintaining stability of the immune system. These species are primary producers of short-chain fatty acids in the human gut, mostly in the form of acetate and propionate. These are important for the maintenance of intestinal homeostasis.171 Both acetate and propionate are potent anti-inflammatory mediators as they inhibit the release of pro-inflammatory cytokines from neutrophils and macrophages.172 Cruz-Bravo et al. described an anti-cancerous role of propionate which induced apoptosis in human colon carcinoma cells.173 Also, butyrate increases expression of tight-junction proteins in the gut to reduce potential gut hyperpermeability. This, in turn, decreases inflammation and endotoxemia that are associated with leaky gut.174 In the human gut, Bacteroides spp. are the principal synthesizers of Vitamin K, which is mainly produced by members of the human gut bacteriome.175 It may prevent or treat osteoporosis by increasing the bone mineral density.176