The breakdown of gliadin peptides by rat intestinal brush-borders in vitro

1984 ◽  
Vol 12 (6) ◽  
pp. 1116-1117 ◽  
Author(s):  
GORDON BRUCE ◽  
JOHN F. WOODLEY
Keyword(s):  
Brush Borders ◽  
Gliadin Peptides

Orogastric challenge of rabbits with human enterotoxigenic Escherichia coli (ETEC) strains that adhere to rabbit brush borders in vitro

1998 ◽  
Vol 114 ◽  
pp. A1082-A1083
Author(s):  
G Semancik ◽  
F Cassels ◽  
H Ryu ◽  
E Fleming ◽  
J Anderson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Enterotoxigenic Escherichia Coli ◽  
Brush Borders

scholarly journals Epithelial transport of immunogenic and toxic gliadin peptides in vitro

2013 ◽  
Vol 27 (S1) ◽  
Author(s):  
Christian Alexander Zimmermann ◽  
Sevgi Arampatzi ◽  
Wolfgang Maison ◽  
Günter Lochnit ◽  
Klaus‐Peter Zimmer ◽  
...  
Keyword(s):  
Epithelial Transport ◽  
Gliadin Peptides

scholarly journals An In Vitro Study on Mitochondrial Compensatory Response Induced by Gliadin Peptides in Caco-2 Cells

2019 ◽  
Vol 20 (8) ◽  
pp. 1862 ◽  
Author(s):  
Orlando ◽  
Chimienti ◽  
Pesce ◽  
Fracasso ◽  
Lezza ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
In Vitro Study ◽  
Peroxisome Proliferator ◽  
Compensatory Response ◽  
Peroxisome Proliferator Activated Receptor ◽  
Strand Breaks ◽  
Abasic Sites ◽  
D Loop ◽  
Gliadin Peptides

Dietary gliadin may show a broad spectrum of toxicity. The interplay between mitochondria and gliadin-induced oxidative stress has not been thoroughly examined in the intestinal epithelium. In this kinetic study, Caco-2 cells were exposed for 24 h to pepsin-trypsin-digested gliadin, alone or in combination with the antioxidant 2,6-di-tbutyl-p-cresol (BHT), and the effects on mitochondrial biogenesis and mtDNA were studied. Cells ability to recover from stress was determined after 24 h and 48 h of incubation in the culture medium. Gliadin-induced oxidative stress evoked a compensatory response. The stressor triggered a rapid and significant increase of Peroxisome proliferator-activated receptor γ coactivator-1alpha (PGC-1α) and Peroxiredoxin III (PrxIII) proteins, and mtDNA amount. As for the effects of gliadin on mtDNA integrity, strand breaks, abasic sites, and modified bases were analyzed in three mtDNA regions. D-loop appeared a more fragile target than Ori-L and ND1/ND2. The temporal trend of the damage at D-loop paralleled that of the amount of mtDNA. Overall, a trend toward control values was shown 48 h after gliadin exposure. Finally, BHT was able to counteract the effects of gliadin. Results from this study highlighted the effects of gliadin-induced oxidative stress on mitochondria, providing valuable evidence that might improve the knowledge of the pathophysiology of gluten-related disorders.

Species Specificity of In Vitro Escherichia coli Adherence to Host Intestinal Cell Membranes and Its Correlation with In Vitro Colonization and Infectivity

1980 ◽  
Vol 28 (3) ◽  
pp. 1019-1027 ◽  
Author(s):  
Christopher P. Cheney ◽  
Peter A. Schad ◽  
Samuel B. Formal ◽  
Edgar C. Boedeker
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cells ◽  
Intestinal Mucosa ◽  
Guinea Pigs ◽  
Species Specificity ◽  
Intestinal Cell ◽  
Resected Specimen ◽  
Brush Borders

We have previously described an in vitro assay for examining the mucosal adherence of a rabbit diarrheagenic Escherichia coli , RDEC-1. That assay defined the in vitro characteristics of RDEC-1 adherence to brush borders isolated from rabbit ileal epithelial cells. The present study was conducted to examine the species specificity of both in vitro RDEC-1 adherence and in vivo infectivity of RDEC-1 and to compare these specificities. Species specificity in vitro adherence was examined by using brush borders prepared from intestinal epithelial cells of rats, guinea pigs, and rabbits, as well as from a surgically resected specimen of human ileum. Strain RDEC-1 adherence to rabbit brush borders in vitro was significantly greater ( P < 0.001) than its adherence to brush borders from any of the other species. Regional specificity of in vitro adherence of RDEC-1 to ileal segments of rabbit intestinal mucosa was also demonstrated. There was significantly greater adherence of RDEC-1 to rabbit ileal brush borders as compared to rabbit jejunal brush borders ( P < 0.05). In vivo infectivity was assessed by inoculating RDEC-1 into rats, guinea pigs, and rabbits. RDEC-1 elicited diarrhea in all inoculated rabbits with the mean onset of illness occurring 5 days after inoculation. In contrast, none of the RDEC-1-inoculated rats or guinea pigs developed diarrhea. Furthermore, colonization studies in these animals revealed that RDEC-1 heavily colonized the ileum and cecum (10 9 RDEC-1 colony-forming units/g of tissue) of rabbits; however, only minimal colonization was observed in guinea pigs and rats. In conclusion, the correlation between in vitro adherence and in vivo infectivity that we have observed suggests that the presence of receptors, specific for bacteria, on the surface of the host intestinal mucosa determines species susceptibility to enteric colonization and infectivity by certain strains of enteropathogenic E. coli .

scholarly journals Nucleated polymerization of actin from the membrane-associated ends of microvillar filaments in the intestinal brush border.

1982 ◽  
Vol 95 (1) ◽  
pp. 223-233 ◽  
Author(s):  
M S Mooseker ◽  
T D Pollard ◽  
K A Wharton
Keyword(s):  
Ionic Strength ◽  
Intestinal Epithelial ◽  
Capping Protein ◽  
The Core ◽  
Nucleated Polymerization ◽  
Myosin Subfragment ◽  
Brush Borders ◽  
Pointed End ◽  
Low Ionic Strength

We examined the nucleated polymerization of actin from the two ends of filaments that comprise the microvillus (MV) core in intestinal epithelial cells by electron microscopy. Three different in vitro preparations were used to nucleate the polymerization of muscle G-actin: (a) MV core fragments containing "barbed" and "pointed" filament ends exposed by shear during isolation, (b) isolated, membrane-intact brush borders, and (c) brush borders demembranated with Triton-X 100. It has been demonstrated that MV core fragments nucleate filament growth from both ends with a strong bias for one end. Here we identify the barbed end of the core fragment as the fast growing end by decoration with myosin subfragment one. Both cytochalasin B (CB) and Acanthamoeba capping protein block filament growth from the barbed but not the pointed end of MV core fragments. To examine actin assembly from the naturally occurring, membrane-associated ends of MV core filaments, isolated membrane-intact brush borders were used to nucleate the polymerization of G-actin. Addition of salt (75 mM KCl, 1 mM MgSO4) to brush borders preincubated briefly at low ionic strength with G-actin induced the formation of 0.2-0.4 micron "growth zones" at the tips of microvilli. The dense plaque at the tip of the MV core remains associated with the membrane and the presumed growing ends of the filaments. We also observed filament growth from the pointed ends of core filaments in the terminal web. We did not observe filament growth at the membrane-associated ends of core filaments when the latter were in the presence of 2 microM CB or if the low ionic strength incubation step was omitted. Addition of G-actin to demembranated brush borders, which retain the dense plaque on their MV tips, resulted in filament growth from both ends of the MV core. Again, 2 microM CB blocked filament growth from only the barbed (tip) end of the core. The dense plaque remained associated with the tip-end of the core in the presence of CB but usually was dislodged in control preparations where nucleated polymerization from the tip-end of the core occurred. Our results support the notion that microvillar assembly and changes in microvillar length could occur by actin monomer addition/loss at the barbed, membrane-associated ends of MV core filaments.

The activities of peptides “31–43”, “44–55” and “56–68” of A-gliadin on In Vitro Cultures of CaCo-2 Cells

1997 ◽  
Vol 25 (4) ◽  
pp. 437-443
Author(s):  
Claudio Giovannini ◽  
Roberto Luchetti ◽  
Massimo De Vincenzi
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequences ◽  
In Vitro Cultures ◽  
The Other ◽  
Suitable Model ◽  
Gliadin Peptide ◽  
Gliadin Peptides ◽  
Active Amino Acid ◽  
Toxic Peptides

In previous studies, various A-gliadin peptides with known amino acid sequences have been tested for their damaging effects on in vitro cultured atrophic coeliac mucosa. The largest common sequences among the in vitro toxic peptides were (gln) 3- pro and pro-ser-(gln)2. Three of these active A-gliadin fragments were synthesised and characterised, namely, the peptides corresponding to the amino acid sequences “31–43” and “44–55”, which contain the sequences (gln)3-rpro and pro-ser-(gln)2, respectively, and the “56–68” fragment lacking both active amino acid sequences. While the “56–68” A-gliadin peptide was completely inactive in CaCo-2 cells, the other two peptides were cytotoxic toward these cells to different extents. Our results confirm that CaCo-2 cells are a suitable model for the identification of toxic peptides responsible for coeliac pathogenesis.

Sign in / Sign up

Export Citation Format

Share Document