Expression of extracellular glutathione peroxidase in human and mouse gastrointestinal tract

Extracellular glutathione peroxidase (EGPx) is a glycosylated selenoprotein capable of reducing hydrogen peroxide, organic hydroperoxides, free fatty acid hydroperoxides, and phosphatidylcholine hydroperoxides. We found that human large intestinal explant cultures synthesize EGPx and cellular glutathione peroxidase (CGPx) and secrete EGPx. The level of EGPx mRNA expression relative to α-tubulin was similar throughout the mouse gastrointestinal tract. EGPx mRNA transcripts have been localized to mature absorptive epithelial cells in human and mouse large intestine. Western blot analysis of mouse intestinal protein has demonstrated the presence of EGPx protein in the small intestine, cecum, and large intestine, with the highest protein levels found in the cecum. Immunohistochemistry studies of human large intestine and mouse small and large intestine sections demonstrated the presence of EGPx protein within mature absorptive epithelial cells. In human large intestine and mouse small intestine, EGPx protein is also present in the extracellular milieu. These results suggest a role for EGPx in protection of the intestinal tract from peroxidative damage and/or in intercellular metabolism of peroxides.

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Epithelial surfaces of the upper gastrointestinal tract of the blue-tongues lizard, Tiliqua scincoides: a scanning electron microscope study

Australian Journal of Zoology ◽

10.1071/zo9780241 ◽

1978 ◽

Vol 26 (2) ◽

pp. 241 ◽

Cited By ~ 5

Author(s):

AS Giraud ◽

CR Hunter ◽

John DJB St

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Epithelial Cells ◽

Gastric Epithelium ◽

Upper Gastrointestinal Tract ◽

Surface Epithelium ◽

Transmission Microscopy ◽

Scanning Electron Microscope Study ◽

Upper Gastrointestinal ◽

Scanning Electron

The surface epithelium of the oesophagus, stomach and small intestine of healty T. scincoides was examined by scanning electron microscopy and the findings confirmed by both light and transmission microscopy. The oesophagus was lined by ciliated, goblet and microvillous cells. Its topography appeared similar to the trachea and major bronchi of a number of mammals and birds. Throughout the length of the stomach microvillous cells were uniformly arranged on the gastric rugae. The cells were slightly convex and sparsely populated by microvilli, which appeared more numerous at intercellular margins. Swollen epithelial cells, approximately twice the size of the adjacent cells, were scattered throughout the gastric epithelium. Cells with focal apical erosions were found in isolated regions, being relatively more numerous in the distal stomach. The openings of the gastric glands were observed as invaginations of the epithelial surface and were most prominent near the tops of the gastric rugae. The small intestine was lined by epithelial cells covered by long, densely packed microvilli. Goblet cells were interspersed along the surface of the intestinal villi. Except for the oesophagus, the topography of the upper gastrointestinal tract of T. scincoides closely resembles that of homologous regions of the mammalian gut.

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Pyrosequencing-based analysis of the complex microbiota located in the gastrointestinal tracts of growing-finishing pigs

Animal Production Science ◽

10.1071/an16799 ◽

2019 ◽

Vol 59 (5) ◽

pp. 870 ◽

Cited By ~ 1

Author(s):

J. Wang ◽

Y. Han ◽

J. Z. Zhao ◽

Z. J. Zhou ◽

H. Fan

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Large Intestine ◽

Production Efficiency ◽

Rrna Gene ◽

Finishing Pigs ◽

Gastrointestinal Microbiota ◽

Bacterial Phyla ◽

Principal Coordinates ◽

Colon And Rectum

The commensal gut microbial communities play an important role in the health and production efficiency of growing-finishing pigs. This study aimed to analyse the composition and diversity of the microbiota in the gastrointestinal tract sections (stomach, duodenum, jejunum, ileum, caecum, colon and rectum) of growing-finishing pigs. This analysis was assessed using 454 pyrosequencing targeting the V3–V6 region of the 16S rRNA gene. Samples were collected from 20, healthy pigs aged 24 weeks and weighing 115.9 ± 5.4 kg. The dominant bacterial phyla in the various gastrointestinal tract sections were Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria. At the genus level, Prevotella, unclassified Lachnospiraceae, Ruminococcus, unclassified Ruminococcaceae and Oscillospira were more abundant in the large intestine than in the stomach and the small intestine. Unclassified Peptostreptococcaceae and Corynebacterium were more abundant in the small intestine than in the stomach and the large intestine. Shuttleworthia, unclassified Veillonellaceae and Mitsuokella were more abundant in the stomach than in the small and large intestines. At the species level, M. el.s.d.enii and M. multacida were predominant in the stomach. In addition, P. stercorea, P. copri, C. butyricum, R. flavefaciens and R. bromii were significantly more abundant in the large intestine than in the stomach and the small intestine. B. pseudolongum and B. thermacidophilum were significantly more abundant in the small intestine than in the stomach and the large intestine. Principal coordinates analysis showed that the overall composition of the pig gastrointestinal microbiota could be clustered into three groups: stomach, small intestine (duodenum, jejunum and ileum) and large intestine (caecum, colon and rectum). Venn diagrams illustrated the distribution of shared and specific operational taxonomic units among the various gastrointestinal tract sections.

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Gastrointestinal physiology

10.1093/med/9780198765875.003.0035 ◽

2017 ◽

Author(s):

Mark Harrison

Keyword(s):

Emergency Medicine ◽

Small Intestine ◽

Gastrointestinal Tract ◽

Large Intestine ◽

Functional Anatomy ◽

Gastrointestinal Physiology

This chapter describes gastrointestinal physiology as it applies to Emergency Medicine, and in particular the Primary FRCEM examination. The chapter outlines the key details of the functional anatomy of the gastrointestinal tract, saliva, swallowing, stomach, small intestine, pancreas, liver, gallbladder, and large intestine. This chapter is laid out exactly following the RCEM syllabus, to allow easy reference and consolidation of learning.

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Glutathione peroxidase-3 produced by the kidney binds to a population of basement membranes in the gastrointestinal tract and in other tissues

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00064.2011 ◽

2011 ◽

Vol 301 (1) ◽

pp. G32-G38 ◽

Cited By ~ 38

Author(s):

Raymond F. Burk ◽

Gary E. Olson ◽

Virginia P. Winfrey ◽

Kristina E. Hill ◽

Dengping Yin

Keyword(s):

Gastrointestinal Tract ◽

Epithelial Cells ◽

Glutathione Peroxidase ◽

Basement Membranes ◽

Seminiferous Tubules ◽

Type I ◽

Rt Pcr ◽

Efferent Ducts ◽

Glutathione Peroxidase 3 ◽

Type Ii Pneumocytes

Glutathione peroxidase-3 (Gpx3), the extracellular glutathione peroxidase synthesized largely in the kidney, binds to basement membranes of renal cortical epithelial cells. The present study assessed extrarenal expression of Gpx3 using RT-PCR and presence of Gpx3 protein using immunocytochemistry. Gpx3 expression was higher in kidney and epididymis than in other tissues. Gpx3 bound to basement membranes of epithelial cells in the gastrointestinal tract, the efferent ducts connecting the seminiferous tubules with the epididymis, the bronchi, and type II pneumocytes. It was not detected on the basement membrane of type I pneumocytes. Gpx3 was also present in the lumen of the epididymis. Transplantation of Gpx3+/+kidneys into Gpx3−/−mice led to Gpx3 binding to the same basement membranes to which it bound in Gpx3+/+mice but not to its presence in the epididymal lumen. These results show that Gpx3 from the blood binds to basement membranes of specific epithelial cells and indicate that the cells modify their basement membranes to cause the binding. They further indicate that at least two Gpx3 compartments exist in the organism. In one compartment, kidney supplies Gpx3 through the blood to specific basement membranes in a number of tissues. In the other compartment, the epididymis provides Gpx3 to its own lumen. Tissues other than kidney and epididymis express Gpx3 at lower levels and may supply Gpx3 to other compartments.

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Gastrointestinal tract protein synthesis and mRNA levels for proteolytic systems in adult fasted rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1996.271.2.e232 ◽

1996 ◽

Vol 271 (2) ◽

pp. E232-E238 ◽

Cited By ~ 10

Author(s):

S. E. Samuels ◽

D. Taillandier ◽

E. Aurousseau ◽

Y. Cherel ◽

Y. Le Maho ◽

...

Keyword(s):

Protein Synthesis ◽

Small Intestine ◽

Gastrointestinal Tract ◽

Mrna Levels ◽

Protein Mass ◽

Fractional Rate ◽

Intestinal Protein ◽

Critical Components ◽

Fasted Rats

We studied protein turnover in the gastrointestinal tract of adult fasted rats, since the mechanisms responsible for protein wasting in these tissues are poorly understood. Protein mass of stomach, small intestine, and colon decreased by 14-29 and 21-49% after 1 and 5 days of fasting, respectively. The fractional rate of in vivo protein synthesis (ks) was approximately 34% lower in the stomach after 1 and 5 days of fasting due to decreased capacity for protein synthesis (Cs). In small intestine and colon, ks was not different after 1 day, but was approximately 26% lower on day 5, mainly because of a reduction in Cs. Thus protein wasting in the stomach is primarily mediated by decreased protein synthesis but not in small intestine and colon during short-term fasting. To determine which proteolytic systems may be activated in the gut, we measured mRNA levels for critical components of the lysosomal (cathepsins B and D), Ca(2+)-activated (m-calpain), and ubiquitin-dependent (ubiquitin, 14-kDa ubiquitin-conjugating enzyme E2, and C8, and C9 proteasome subunits) proteolytic pathways. mRNA levels for most of these components increased during fasting, suggesting that a coordinated activation of multiple proteolytic systems contributed to intestinal protein wasting.

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Chlamydia Deficient in Plasmid-Encoded pGP3 Is Prevented from Spreading to Large Intestine

Infection and Immunity ◽

10.1128/iai.00120-20 ◽

2020 ◽

Vol 88 (6) ◽

Author(s):

Zhi Huo ◽

Conghui He ◽

Ying Xu ◽

Tianjun Jia ◽

Jie Wang ◽

...

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Large Intestine ◽

Oral Inoculation ◽

Mouse Small Intestine ◽

Small Intestinal ◽

Gastric Barrier ◽

Better Than ◽

Do So ◽

Live Organism

ABSTRACT The cryptic plasmid pCM is critical for chlamydial colonization in the gastrointestinal tract. Nevertheless, orally inoculated plasmid-free Chlamydia sp. was still able to colonize the gut. Surprisingly, orally inoculated Chlamydia sp. deficient in only plasmid-encoded pGP3 was no longer able to colonize the gut. A comparison of live organism recoveries from individual gastrointestinal tissues revealed that pGP3-deficient Chlamydia sp. survived significantly better than plasmid-free Chlamydia sp. in small intestinal tissues. However, the small intestinal pGP3-deficient Chlamydia sp. failed to reach the large intestine, explaining the lack of live pGP3-deficient Chlamydia sp. in rectal swabs following an oral inoculation. Interestingly, pGP3-deficient Chlamydia sp. was able to colonize the colon following an intracolon inoculation, suggesting that pGP3-deficient Chlamydia sp. might be prevented from spreading from the small intestine to the large intestine. This hypothesis is supported by the finding that following an intrajejunal inoculation that bypasses the gastric barrier, pGP3-deficient Chlamydia sp. still failed to reach the large intestine, although similarly inoculated plasmid-free Chlamydia sp. was able to do so. Interestingly, when both types of organisms were intrajejunally coinoculated into the same mouse small intestine, plasmid-free Chlamydia sp. was no longer able to spread to the large intestine, suggesting that pGP3-deficient Chlamydia sp. might be able to activate an intestinal resistance for regulating Chlamydia sp. spreading. Thus, the current study has not only provided evidence for reconciling a previously identified conflicting phenotype but also revealed a potential intestinal resistance to chlamydial spreading. Efforts are under way to further define the mechanism of the putative intestinal resistance.

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Digesta transit in different segments of the gastrointestinal tract of pigs as affected by insoluble fibre supplied by wheat bran

British Journal Of Nutrition ◽

10.1017/s0007114507682981 ◽

2007 ◽

Vol 98 (1) ◽

pp. 54-62 ◽

Cited By ~ 100

Author(s):

Aurélie Wilfart ◽

Lucile Montagne ◽

Howard Simmins ◽

Jean Noblet ◽

Jaap van Milgen

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Liquid Phase ◽

Large Intestine ◽

Dietary Fibre ◽

Solid Phase ◽

Latin Square ◽

Fibre Content ◽

Liquid Phases ◽

Insoluble Fibre

Digestibility is the result of two competing processes: digestion and digesta transit. To develop or parameterise mechanistic models of digestion, both processes have to be quantified. The aim of this study was to determine the effect of insoluble dietary fibre on the transit in the gastrointestinal tract of pigs. Six barrows (33 kg initial body weight and fitted with two simple T-cannulas at the proximal duodenum and distal ileum) were used in a double 3 × 3 Latin square design. Pigs were offered diets differing in total dietary fibre content (170, 220 and 270 g/kg DM) at 4 h intervals. A single meal marked with YbO2and Cr-EDTA was used to determine the kinetics of markers concentrations of the solid and liquid phases, respectively. The mean retention time (MRT), calculated by the method of the moments, averaged 1, 4 and 38 h in the stomach, small intestine and large intestine, respectively. Increasing the insoluble fibre content in the diet had no effect on MRT in the stomach and decreased the MRT of both phases in the small intestine (P < 0·05). In the large intestine, increasing the insoluble fibre content decreased the MRT of the liquid phase (P = 0·02) and tended to decrease the MRT of the solid phase (P = 0·06). Transit of the solid phase in the large intestine was 4–8 h slower than transit of the liquid phase. Analysis of marker excretion curves indicated that the small and large intestine should be represented mathematically to have both a tubular (propulsion) and compartmental (mixing) structure.

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Comparative gross morphology of the digestive tract in ten Didelphidae marsupial species

Mammalia ◽

10.1515/mamm.2004.004 ◽

2004 ◽

Vol 68 (1) ◽

Cited By ~ 12

Author(s):

R.T. Santori ◽

D. Astua De Moraes ◽

Rui Cerqueira

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Digestive Tract ◽

Large Intestine ◽

Food Habits ◽

Relative Size ◽

Marsupial Species

Natural diets of Didelphidae species vary in the amounts of invertebrates, fruits and small vertebrates eaten. We investigated the digestive morphology of ten species of didelphid marsupials varying in food habits. The purpose was to describe and to compare the shape and relative size of the digestive tract portions among species studied and relate them to food habits. The form of the gastrointestinal tract in this family is simple, with a unilocular stomach, small intestine, large intestine and caecum.

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A Metabolomic-Based Evaluation of the Role of Commensal Microbiota throughout the Gastrointestinal Tract in Mice

Microorganisms ◽

10.3390/microorganisms6040101 ◽

2018 ◽

Vol 6 (4) ◽

pp. 101 ◽

Cited By ~ 10

Author(s):

Yuri Yamamoto ◽

Yumiko Nakanishi ◽

Shinnosuke Murakami ◽

Wanping Aw ◽

Tomoya Tsukimi ◽

...

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Large Intestine ◽

Rrna Gene ◽

Commensal Microbiota ◽

Flight Mass Spectrometry ◽

Specific Pathogen ◽

Gastrointestinal Microbes ◽

Small And Large Intestine

Commensal microbiota colonize the surface of our bodies. The inside of the gastrointestinal tract is one such surface that provides a habitat for them. The gastrointestinal tract is a long organ system comprising of various parts, and each part possesses various functions. It has been reported that the composition of intestinal luminal metabolites between the small and large intestine are different; however, comprehensive metabolomic and commensal microbiota profiles specific to each part of the gastrointestinal lumen remain obscure. In this study, by using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS)-based metabolome and 16S rRNA gene-based microbiome analyses of specific pathogen-free (SPF) and germ-free (GF) murine gastrointestinal luminal profiles, we observed the different roles of commensal microbiota in each part of the gastrointestinal tract involved in carbohydrate metabolism and nutrient production. We found that the concentrations of most amino acids in the SPF small intestine were higher than those in the GF small intestine. Furthermore, sugar alcohols such as mannitol and sorbitol accumulated only in the GF large intestine, but not in the SPF large intestine. On the other hand, pentoses, such as arabinose and xylose, gradually accumulated from the cecum to the colon only in SPF mice, but were undetected in GF mice. Correlation network analysis between the gastrointestinal microbes and metabolites showed that niacin metabolism might be correlated to Methylobacteriaceae. Collectively, commensal microbiota partially affects the gastrointestinal luminal metabolite composition based on their metabolic dynamics, in cooperation with host digestion and absorption.

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Gastrointestinal physiology

Revision Notes for MCEM Part A ◽

10.1093/med/9780199583836.003.0035 ◽

2011 ◽

pp. 287-308

Author(s):

Dr Mark Harrison

Keyword(s):

Small Intestine ◽

Gastrointestinal Tract ◽

Large Intestine ◽

General Structure ◽

Functional Anatomy ◽

Gastrointestinal Physiology

4.1 Functional anatomy of the gastrointestinal tract - outline of structure, 288 4.2 Saliva, 289 4.3 Swallowing (deglutition), 292 4.4 Stomach, 293 4.5 Small intestine, 297 4.6 Pancreas, 300 4.7 Liver, 302 4.8 Gallbladder, 305 4.9 Large intestine, 306 • The gastrointestinal tract has a fairly consistent general structure that is arranged into 4 concentric layers (see Figure ...

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