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Nutrients Apr 2019Sports nutrition products are developed and targeted mainly for athletes to improve their nutrient intake, performance, and muscle growth. The fastest growing consumer... (Review)
Review
Sports nutrition products are developed and targeted mainly for athletes to improve their nutrient intake, performance, and muscle growth. The fastest growing consumer groups for these products are recreational sportspeople and lifestyle users. Although athletes may have elevated physiological protein requirements and they may benefit from dietary supplements, the evidence regarding the role of dietary protein and supplements in the nutrition of recreational sportspeople and sedentary populations is somewhat complex and contradictory. In high-protein diets, more undigested protein-derived constituents end up in the large intestine compared to moderate or low-protein diets, and hence, more bacterial amino acid metabolism takes place in the colon, having both positive and negative systemic and metabolic effects on the host. The aim of the present review is to summarize the impact of the high-protein products and diets on nutrition and health, in sportspeople and in sedentary consumers. We are opening the debate about the current protein intake recommendations, with an emphasis on evidence-based effects on intestinal microbiota and personalized guidelines regarding protein and amino acid supplementation in sportspeople and lifestyle consumers.
Topics: Amino Acids; Bacteria; Dietary Proteins; Dietary Supplements; Digestion; Exercise; Gastrointestinal Microbiome; Humans; Intestine, Large; Nutritional Status; Recommended Dietary Allowances; Sedentary Behavior; Sports; Sports Nutritional Physiological Phenomena
PubMed: 31013719
DOI: 10.3390/nu11040829 -
Gut Oct 1987Evidence for the occurrence of microbial breakdown of carbohydrate in the human colon has been sought by measuring short chain fatty acid (SCFA) concentrations in the...
Evidence for the occurrence of microbial breakdown of carbohydrate in the human colon has been sought by measuring short chain fatty acid (SCFA) concentrations in the contents of all regions of the large intestine and in portal, hepatic and peripheral venous blood obtained at autopsy of sudden death victims within four hours of death. Total SCFA concentration (mmol/kg) was low in the terminal ileum at 13 +/- 6 but high in all regions of the colon ranging from 131 +/- 9 in the caecum to 80 +/- 11 in the descending colon. The presence of branched chain fatty acids was also noted. A significant trend from high to low concentrations was found on passing distally from caecum to descending colon. pH also changed with region from 5.6 +/- 0.2 in the caecum to 6.6 +/- 0.1 in the descending colon. pH and SCFA concentrations were inversely related. Total SCFA (mumol/l) in blood was, portal 375 +/- 70, hepatic 148 +/- 42 and peripheral 79 +/- 22. In all samples acetate was the principal anion but molar ratios of the three principal SCFA changed on going from colonic contents to portal blood to hepatic vein indicating greater uptake of butyrate by the colonic epithelium and propionate by the liver. These data indicate that substantial carbohydrate, and possibly protein, fermentation is occurring in the human large intestine, principally in the caecum and ascending colon and that the large bowel may have a greater role to play in digestion than has previously been ascribed to it.
Topics: Acetates; Acetic Acid; Animals; Butyrates; Butyric Acid; Fatty Acids; Female; Fermentation; Gastrointestinal Contents; Hepatic Veins; Humans; Hydrogen-Ion Concentration; Intestine, Large; Male; Portal Vein; Propionates; Swine
PubMed: 3678950
DOI: 10.1136/gut.28.10.1221 -
Nature Communications Apr 2023The intestinal lamina propria contains a diverse network of fibroblasts that provide key support functions to cells within their local environment. Despite this, our...
The intestinal lamina propria contains a diverse network of fibroblasts that provide key support functions to cells within their local environment. Despite this, our understanding of the diversity, location and ontogeny of fibroblasts within and along the length of the intestine remains incomplete. Here we show that the small and large intestinal lamina propria contain similar fibroblast subsets that locate in specific anatomical niches. Nevertheless, we find that the transcriptional profile of similar fibroblast subsets differs markedly between the small intestine and colon suggesting region specific functions. We perform in vivo transplantation and lineage-tracing experiments to demonstrate that adult intestinal fibroblast subsets, smooth muscle cells and pericytes derive from Gli1-expressing precursors present in embryonic day 12.5 intestine. Trajectory analysis of single cell RNA-seq datasets of E12.5 and adult mesenchymal cells suggest that adult smooth muscle cells and fibroblasts derive from distinct embryonic intermediates and that adult fibroblast subsets develop in a linear trajectory from CD81 fibroblasts. Finally, we provide evidence that colonic subepithelial PDGFRα fibroblasts comprise several functionally distinct populations that originate from an Fgfr2-expressing fibroblast intermediate. Our results provide insights into intestinal stromal cell diversity, location, function, and ontogeny, with implications for intestinal development and homeostasis.
Topics: Colon; Fibroblasts; Intestine, Large; Intestine, Small; Intestines; Zinc Finger Protein GLI1; Mesenchymal Stem Cells
PubMed: 37085516
DOI: 10.1038/s41467-023-37952-5 -
International Journal of Molecular... Jul 2020The large intestine, part of the gastrointestinal tract (GI), is composed of all three germ layers, namely the endoderm, the mesoderm and the ectoderm, forming the... (Review)
Review
The large intestine, part of the gastrointestinal tract (GI), is composed of all three germ layers, namely the endoderm, the mesoderm and the ectoderm, forming the epithelium, the smooth muscle layers and the enteric nervous system, respectively. Since gastrulation, these layers develop simultaneously during embryogenesis, signaling to each other continuously until adult age. Two invaginations, the anterior intestinal portal (AIP) and the caudal/posterior intestinal portal (CIP), elongate and fuse, creating the primitive gut tube, which is then patterned along the antero‑posterior (AP) axis and the radial (RAD) axis in the context of left‑right (LR) asymmetry. These events lead to the formation of three distinct regions, the foregut, midgut and hindgut. All the above‑mentioned phenomena are under strict control from various molecular pathways, which are critical for the normal intestinal development and function. Specifically, the intestinal epithelium constitutes a constantly developing tissue, deriving from the progenitor stem cells at the bottom of the intestinal crypt. Epithelial differentiation strongly depends on the crosstalk with the adjacent mesoderm. Major molecular pathways that are implicated in the embryogenesis of the large intestine include the canonical and non‑canonical wingless‑related integration site (Wnt), bone morphogenetic protein (BMP), Notch and hedgehog systems. The aberrant regulation of these pathways inevitably leads to several intestinal malformation syndromes, such as atresia, stenosis, or agangliosis. Novel theories, involving the regulation and homeostasis of intestinal stem cells, suggest an embryological basis for the pathogenesis of colorectal cancer (CRC). Thus, the present review article summarizes the diverse roles of these molecular factors in intestinal embryogenesis and related disorders.
Topics: Animals; Bone Morphogenetic Proteins; Colorectal Neoplasms; Humans; Intestine, Large; Signal Transduction
PubMed: 32319546
DOI: 10.3892/ijmm.2020.4583 -
Gut Microbes 2022The utilization of dietary cellulose by resident bacteria in the large intestine of mammals, both herbivores and omnivores (including humans), has been a subject of... (Review)
Review
The utilization of dietary cellulose by resident bacteria in the large intestine of mammals, both herbivores and omnivores (including humans), has been a subject of interest since the nineteenth century. Cellulolytic bacteria are key participants in this breakdown process of cellulose, which is otherwise indigestible by the host. They critically contribute to host nutrition and health through the production of short-chain fatty acids, in addition to maintaining the balance of intestinal microbiota. Despite this key role, cellulolytic bacteria have not been well studied. In this review, we first retrace the history of the discovery of cellulolytic bacteria in the large intestine. We then focus on the current knowledge of cellulolytic bacteria isolated from the large intestine of various animal species and humans and discuss the methods used for isolating these bacteria. Moreover, we summarize the enzymes and the mechanisms involved in cellulose degradation. Finally, we present the contribution of these bacteria to the host.
Topics: Animals; Bacteria; Cellulose; Gastrointestinal Microbiome; Humans; Intestine, Large; Mammals
PubMed: 35184689
DOI: 10.1080/19490976.2022.2031694 -
World Journal of Gastroenterology Nov 2014The small and large intestine of the gastrointestinal tract (GIT) have evolved to have discrete functions with distinct anatomies and immune cell composition. The... (Review)
Review
The small and large intestine of the gastrointestinal tract (GIT) have evolved to have discrete functions with distinct anatomies and immune cell composition. The importance of these differences is underlined when considering that different pathogens have uniquely adapted to live in each region of the gut. Furthermore, different regions of the GIT are also associated with differences in susceptibility to diseases such as cancer and chronic inflammation. The large and small intestine, given their anatomical and functional differences, should be seen as two separate immunological sites. However, this distinction is often ignored with findings from one area of the GIT being inappropriately extrapolated to the other. Focussing largely on the murine small and large intestine, this review addresses the literature relating to the immunology and biology of the two sites, drawing comparisons between them and clarifying similarities and differences. We also highlight the gaps in our understanding and where further research is needed.
Topics: Animals; Epithelial Cells; Homeostasis; Host-Pathogen Interactions; Inflammatory Bowel Diseases; Intestinal Mucosa; Intestinal Neoplasms; Intestine, Large; Intestine, Small; Mice; Microbiota
PubMed: 25386070
DOI: 10.3748/wjg.v20.i41.15216 -
Cell Reports. Medicine Sep 2023Research on gut microbiota has generally focused on fecal samples, representing luminal content of the large intestine. However, nutrient uptake is restricted to the... (Review)
Review
Research on gut microbiota has generally focused on fecal samples, representing luminal content of the large intestine. However, nutrient uptake is restricted to the small intestine. Abundant immune cell populations at this anatomical site combined with diminished mucus secretion and looser junctions (partly to allow for more efficient fluid and nutrient absorption) also results in intimate host-microbe interactions despite more rapid transit. It is thus crucial to dissect key differences in both ecology and physiology between small and large intestine to better leverage the immense potential of human gut microbiota imprinting, including probiotic engraftment at biological sensible niches. Here, we provide a detailed review unfolding how the physiological and anatomical differences between the small and large intestine affect gut microbiota composition, function, and plasticity. This information is key to understanding how gut microbiota manipulation, including probiotic administration, may strain-dependently transform host-microbe interactions at defined locations.
Topics: Humans; Colon; Intestine, Small; Biological Transport; Feces; Probiotics
PubMed: 37683651
DOI: 10.1016/j.xcrm.2023.101190 -
Journal of B.U.ON. : Official Journal... 2020Gastrointestinal stromal tumors (GISTs) of the large intestine are extremely rare entities that constitute approximately 5% of the reported GISTs and approximately 0.1%... (Review)
Review
Gastrointestinal stromal tumors (GISTs) of the large intestine are extremely rare entities that constitute approximately 5% of the reported GISTs and approximately 0.1% of all cancers of colon and rectum. Almost 85-95% of GISTs contain a mutation in the c-kit tyrosine kinase and positive expression of the CD117 antigen (c-KIT). About 5% of GISTs appear to be c-kit-negative and usually have a mutation on the platelet-derived growth factor receptor-a (PDGFR-a). Compared to other GISTs, GISTs of the colon demonstrate different prevalence, incidence between various population subgroups, clinical appearance, molecular biology, treatment and prognosis. These parameters differ further depending on the GISTs primary site (colon, rectum or anus). The aim of this article was to review the current literature of those rare tumors.
Topics: Gastrointestinal Stromal Tumors; Humans; Intestine, Large
PubMed: 32277610
DOI: No ID Found -
International Journal of Environmental... Aug 2022The rat tapeworm has been shown to cause alterations in gastrointestinal tissues. Since hymenolepiasis induces a number of reactions in the host, it is reasonable to...
The rat tapeworm has been shown to cause alterations in gastrointestinal tissues. Since hymenolepiasis induces a number of reactions in the host, it is reasonable to assume that it may also be involved in the mechanisms of apoptosis in the intestines. Individual research tasks included an examination of the effect of infection on; (i) the cellular localization of the expression of pro-apoptotic protein Bax and anti-apoptotic protein Bcl-2, as well as caspase-3 and caspase-9, and (ii) the effects of the infection on the expression of Bcl-2, Bax, Cas-3 and Cas-9, at the mRNA and protein levels. Molecular tests (including mRNA (qRT PCR) and the protein (Western blot) expression of Bax, Bcl-2, and caspases-3, -9) and immunohistochemical tests were performed during the experiment. They showed that infection activates the intrinsic apoptosis pathway in the small and large intestine of the host. infection triggered the apoptosis via the activation of the caspase cascade, including Cas-3 and Cas-9. Hymenolepiasis enhanced apoptosis in the small and large intestine of the host by increasing the expression of the pro-apoptotic gene and protein Bax and by decreasing the expression of the anti-apoptotic gene and protein Bcl-2.
Topics: Animals; Apoptosis; Hymenolepiasis; Hymenolepis diminuta; Intestine, Large; RNA, Messenger; Rats; bcl-2-Associated X Protein
PubMed: 35955110
DOI: 10.3390/ijerph19159753 -
BMC Microbiology Apr 2019Methane emissions from pigs account for 10% of total methane production from livestock in China. Methane emissions not only contribute to global warming, as it has 25...
BACKGROUND
Methane emissions from pigs account for 10% of total methane production from livestock in China. Methane emissions not only contribute to global warming, as it has 25 times the global warming potential (GWP) of CO, but also represent approximately 0.1~3.3% of digestive energy loss. Methanogens also play an important role in maintaining the balance of the gut microbiome. The large intestines are the main habitat for the microbiome in pigs. Thus, to better understand the mechanism of methane production and mitigation, generic-specific and physio-ecological characteristics (including redox potential (Eh), pH and volatile fatty acids (VFAs)) and methanogens in the large intestine of pig were studied in this paper. Thirty DLY finishing pigs with the same diet and feeding conditions were selected for this experiment.
RESULT
A total of 219 clones were examined using the methyl coenzyme reductase subunit A gene (mcrA) and assigned to 43 operational taxonomic units (OTUs) based on a 97% species-level identity criterion. The family Methanobacteriaceae was the dominant methanogen in colonic digesta of finishing pigs, accounting for approximately 70.6% of the identified methanogens, and comprised mainly the genera Methanobrevibacter (57%) and Methanosphaera (14%). The order Methanomassiliicoccales, classified as an uncultured taxonomy, accounted for 15.07%. The methanogenic archaeon WGK1 and unclassified Methanomicrobiales belonging to the order of Methanomicrobiales accounted for 4.57 and 1.37%, respectively. The Eh was negative and within the range - 297.00~423.00 mV and the pH was within the range 5.04~6.97 in the large intestine. The populations of total methanogens and Methanobacteriales were stable in different parts of the large intestine according to real-time PCR.
CONCLUSION
The major methanogen in the large intestine of finishing pigs was Methanobrevibacter. The seventh order Methanomassiliicoccales and species Methanosphaera stadtmanae present in the large intestine of pigs might contribute to the transfer of hydrogen and fewer methane emissions. The redox potential (Eh) was higher in the large intestine of finishing pigs, which had a positive correlation with the population of Methanobacteriale.
Topics: Animals; China; Colon; DNA Restriction Enzymes; DNA, Ribosomal; Fatty Acids, Volatile; Female; Gastrointestinal Microbiome; Hydrogen-Ion Concentration; Intestine, Large; Male; Methane; Methanobacteriaceae; Methanobrevibacter; Oxidation-Reduction; Phylogeny; RNA, Ribosomal, 16S; Swine
PubMed: 31035941
DOI: 10.1186/s12866-019-1459-x