Regulation of Probiotics on Metabolism of Dietary Protein in Intestine

Proteins are indispensable components of living organisms, which are derived mainly from diet through metabolism. Dietary proteins are degraded by endogenous digestive enzymes to di- or tripeptides and free amino acids (AAs) in the small intestine lumen and then absorbed into blood and lymph through intestinal epithelial cells via diverse transporters. Microorganisms are involved not only in the proteins’ catabolism, but also the AAs, especially essential AAs, anabolism. Probiotics regulate these processes by providing exogenous proteases and AAs and peptide transporters, and reducing hazardous substances in the food and feed. But the core mechanism is modulating of the composition of intestinal microorganisms through their colonization and exclusion of pathogens. The other effects of probiotics are associated with normal intestinal morphology, which implies that the enterocytes secrete more enzymes to decompose dietary proteins and absorb more nutrients.

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The Fine-Structural Organization of the Brush Border of Intestinal Epithelial Cells

Journal of Cell Science ◽

10.1242/jcs.8.3.573 ◽

1971 ◽

Vol 8 (3) ◽

pp. 573-599

Author(s):

T. M. MUKHERJEE ◽

L. A. STAEHELIN

Keyword(s):

Plasma Membrane ◽

Epithelial Cells ◽

Brush Border ◽

Intestinal Epithelial Cells ◽

Membrane Surface ◽

Intestinal Epithelial ◽

The Core ◽

Unit Structure ◽

Terminal Web ◽

Freeze Etching

The fine structure of the brush border of intestinal epithelial cells of the mouse has been studied with both normal sectioning and freeze-etching techniques. Freeze-etching reveals the plasma membrane of the microvilli as consisting of a continuous layer, that is split during the cleaving process, in which numerous particles, 5-9 nm in diameter, are embedded, while other particle-like structures, with diameters of 7-10 nm, appear attached to the true outer membrane surface. The mucopolysaccharide surface coats of the microvilli show up more clearly in sectioned material than in freeze-etched specimens. Inside each microvillus 2 different filament systems can be demonstrated: (1) bundles of fairly closely packed and straight core microfilaments, which lead into the tip of the microvillus, and (2) short cross-filaments. Under suitable conditions the core microfilaments display a sub-unit structure with a repeating distance of approximately 6 nm. The diameter of a microfilament can vary along its length from 6 to 11 nm. Two strands of globular particles wound helically around each other seem to make up each microfilament. These and other data support the idea that the core microfilaments are actin-like. No substructure has been found on the cross-filaments, which have an orientation approximately radial to the axis of the microvilli and seem to be attached at one end to the core microfilaments and at the other to the inner surface of the microvillous membrane. The interwoven terminal web filaments also show no substructure. They form a continuous flexible platform-like structure into which the bundles of core microfilaments extend. Some terminal web filaments appear attached to the plasma membrane between the microvilli. It is suggested that the core microfilaments represent mechanical supporting elements and that the terminal web and cross-filaments are tensile elements of the brush border. In addition all 3 filament systems may also be involved in possible contractile movements of the microvilli.

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Histo-architectural changes of intestinal morphology in Zebra fish (Danio rerio) exposed to Sumithion

Research in Agriculture Livestock and Fisheries ◽

10.3329/ralf.v2i3.26174 ◽

2015 ◽

Vol 2 (3) ◽

pp. 499-506 ◽

Cited By ~ 3

Author(s):

Sk Istiaque Ahmed ◽

Mirja Kaizer Ahmmed ◽

Subrata Kumar Ghosh ◽

Md Moudud Islam ◽

Md Shahjahan

Keyword(s):

Danio Rerio ◽

Agricultural Land ◽

Intestinal Epithelial Cells ◽

Intestinal Morphology ◽

Total Alkalinity ◽

Intestinal Epithelial ◽

Zebra Fish ◽

Control Groups ◽

Treatment Groups ◽

Organophosphorous Pesticide

Organophosphorous pesticide sumithion, the O, O Dimethyl O- (3-methyl-4-nitrophenyl), is a widely used pesticide in agricultural land and in aquaculture to control some harmful pests. A study was conducted in laboratory condition with aquaria (36 inch × 10 inch × 12 inch) to evaluate the effects of sumithion on histo-architecture of intestine in zebrafish (Danio rerio). The experiment was carried out with three treatments (T1: 0.5 ppm, T2: 1.0 ppm, T3: 2.0 ppm) and a control (T0: 0ppm), each having three replications. Zebra fishes (Danio rerio) (4±1cm and 0.9±0.2g) were stocked for the experiment and sacrificed after 7 days of exposure of sumithion. During the study period, the temperature was almost constant (21- 22OC) but dissolved oxygen, pH and total alkalinity values were tended to decrease with the increase in concentrations of test chemicals. The histo-architectural changes in intestine suggested that the intestinal epithelial cells, lumen, villi and intestinal folding were varied significantly (P<0.05) in treatment groups rather than the control groups (T0). Disappeared mucosa (DM) along with abnormal lumen (AL) were found in case of T1, while destructed intestinal villi (DV), sloughing of superficial epidermal cells (SEC) and uneven intestinal folding (UF) were found in T2 and T3. The obtained result supports the toxic potentiality of sumithion. Therefore, the use of sumithion must be evaluated carefully in agriculture and aquaculture.Res. Agric., Livest. Fish.2(3): 499-506, December 2015

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Benzoic Acid Used as Food and Feed Additives Can Regulate Gut Functions

BioMed Research International ◽

10.1155/2019/5721585 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6 ◽

Cited By ~ 10

Author(s):

Xiangbing Mao ◽

Qing Yang ◽

Daiwen Chen ◽

Bing Yu ◽

Jun He

Keyword(s):

Enzyme Activity ◽

Epithelial Cells ◽

Benzoic Acid ◽

Intestinal Epithelial Cells ◽

Redox Status ◽

Feed Additives ◽

Intestinal Epithelial ◽

Gut Health ◽

Food And Feed ◽

Antibacterial And Antifungal

As a kind of antibacterial and antifungal preservative, benzoic acid is widely used in foods and feeds. Recently, many studies showed that it could improve the growth and health, which should, at least partially, be derived from the promotion of gut functions, including digestion, absorption, and barrier. Based on the similarity of gut physiology between human and pigs, many relative studies in which piglets and porcine intestinal epithelial cells were used as the models have been done. And the results showed that using appropriate benzoic acid levels might improve gut functions via regulating enzyme activity, redox status, immunity, and microbiota, but excess administration would lead to the damage of gut health through redox status. However, the further mechanisms that some intestinal physiological functions might be regulated are not well understood. The present review will, in detail, summarize the effect of benzoic acid on gut functions.

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HIF-Dependent NFATC1 Activation Upregulates ITGA5 and PLAUR in Intestinal Epithelium in Inflammatory Bowel Disease

Frontiers in Genetics ◽

10.3389/fgene.2021.791640 ◽

2021 ◽

Vol 12 ◽

Author(s):

Evgeny Knyazev ◽

Diana Maltseva ◽

Maria Raygorodskaya ◽

Maxim Shkurnikov

Keyword(s):

Inflammatory Bowel Disease ◽

Rna Sequencing ◽

Intestinal Epithelium ◽

Bowel Disease ◽

Intestinal Epithelial Cells ◽

Core Gene ◽

Intestinal Epithelial ◽

Gene Set ◽

The Core ◽

Inflammatory Bowel

Intestinal epithelial cells exist in physiological hypoxia, leading to hypoxia-inducible factor (HIF) activation and supporting barrier function and cell metabolism of the intestinal epithelium. In contrast, pathological hypoxia is a common feature of some chronic disorders, including inflammatory bowel disease (IBD). This work was aimed at studying HIF-associated changes in the intestinal epithelium in IBD. In the first step, a list of genes responding to chemical activation of hypoxia was obtained in an in vitro intestinal cell model with RNA sequencing. Cobalt (II) chloride and oxyquinoline treatment of both undifferentiated and differentiated Caco-2 cells activate the HIF-signaling pathway according to gene set enrichment analysis. The core gene set responding to chemical hypoxia stimulation in the intestinal model included 115 upregulated and 69 downregulated genes. Of this set, protein product was detected for 32 genes, and fold changes in proteome and RNA sequencing significantly correlate. Analysis of publicly available RNA sequencing set of the intestinal epithelial cells of patients with IBD confirmed HIF-1 signaling pathway activation in sigmoid colon of patients with ulcerative colitis and terminal ileum of patients with Crohn’s disease. Of the core gene set from the gut hypoxia model, expression activation of ITGA5 and PLAUR genes encoding integrin α5 and urokinase-type plasminogen activator receptor (uPAR) was detected in IBD specimens. The interaction of these molecules can activate cell migration and regenerative processes in the epithelium. Transcription factor analysis with the previously developed miRGTF tool revealed the possible role of HIF1A and NFATC1 in the regulation of ITGA5 and PLAUR gene expression. Detected genes can serve as markers of IBD progression and intestinal hypoxia.

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Membrane-bound vesicles associated with the microvilli in the midgut of the freshwater microcrustacean, Daphnia magna

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076135 ◽

1983 ◽

Vol 41 ◽

pp. 480-481

Author(s):

Patricia L. Jansma

Keyword(s):

Daphnia Magna ◽

Intestinal Epithelial Cells ◽

Uranyl Acetate ◽

Intestinal Epithelial ◽

Chlamydomonas Reinhardii ◽

Thin Sections ◽

Saturated Water ◽

Cacodylate Buffer ◽

Membrane Bound ◽

Ethanol Series

The presence of the membrane bound vesicles or blebs on the intestinal epithelial cells has been demonstrated in a variety of vertebrates such as chicks, piglets, hamsters, and humans. The only invertebrates shown to have these microvillar blebs are two species of f1ies. While investigating the digestive processes of the freshwater microcrustacean, Daphnia magna, the presence of these microvillar blebs was noticed.Daphnia magna fed in a suspension of axenically grown green alga, Chlamydomonas reinhardii for one hour were narcotized with CO2 saturated water. The intestinal tracts were excised in 2% glutaraldehyde in 0.2 M cacodyl ate buffer and then placed in fresh 2% glutaraldehyde for one hour. After rinsing in 0.1 M cacodylate buffer, the sample was postfixed in 2% OsO4, dehydrated with a graded ethanol series, infiltrated and embedded with Epon-Araldite. Thin sections were stained with uranyl acetate and Reynolds lead citrate before viewing with the Philips EM 200.

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Three-dimensional organization and functional relationships of endocytotic compartments in pig intestinal epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123283 ◽

1992 ◽

Vol 50 (1) ◽

pp. 576-577

Author(s):

Julian P. Heath ◽

Buford L. Nichols ◽

László G. Kömüves

Keyword(s):

Electron Microscopy ◽

Epithelial Cells ◽

Intestinal Epithelial Cells ◽

Three Dimensional ◽

Intestinal Epithelial ◽

Cell Surfaces ◽

Basal Surface ◽

Functional Relationships

The newborn pig intestine is adapted for the rapid and efficient absorption of nutrients from colostrum. In enterocytes, colostral proteins are taken up into an apical endocytotic complex of channels that transports them to target organelles or to the basal surface for release into the circulation. The apical endocytotic complex of tubules and vesicles clearly is a major intersection in the routes taken by vesicles trafficking to and from the Golgi, lysosomes, and the apical and basolateral cell surfaces.Jejunal tissues were taken from piglets suckled for up to 6 hours and prepared for electron microscopy and immunocytochemistry as previously described.

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