Probiotic factors partially prevent changes to caspases 3 and 7 activation and transepithelial electrical resistance in a model of 5-fluorouracil-induced epithelial cell damage.

The potential efficacy of a probiotic-based preventative strategy against intestinal mucositis has yet to be investigated in detail. We evaluated supernatants (SN) from Escherichia coli Nissle 1917 (EcN) and Lactobacillus rhamnosus GG (LGG) for their capacity to prevent 5-fluorouracil (5-FU)-induced damage to intestinal epithelial cells. A 5-day study was performed.

Rapid disruption of intestinal barrier function by gliadin involves altered expression of apical junctional proteins.

Coeliac disease is a chronic enteropathy caused by the ingestion of wheat gliadin and other cereal prolamines derived from rye and barley. In the present work, we investigated the mechanisms underlying altered barrier function properties exerted by gliadin-derived peptides in human Caco-2 intestinal epithelial cells. We demonstrate that gliadin alters barrier function almost immediately by decreasing transepithelial resistance and increasing permeability to small molecules (4 kDa).

Expression of the homeobox gene barx2 in the gut.

Barx2 is a member of the Bar class of homeobox genes and has been shown to regulate specific cell adhesion molecules, L1, Ng-CAM, N-CAM, and cadherin 6. By Northern blotting and in situ hybridization, we show that Barx2 is expressed throughout the gut and is located in epithelial cells of the proliferative and differentiative regions of the stomach, esophagus, and intestine. Barx2 was expressed in muscle cells of the muscularis externa and also showed a graded pattern of expression in intestinal enterocytes, decreasing in a crypt-to-villous direction.

Expression of notch receptors and ligands in the adult gut.

The Notch signaling pathway has become recognized as a vitally important pathway in regulating proliferative/differentiative decisions and cell fate. To explore the involvement of the Notch pathway in adult gut, we investigated the expression of Notch receptors and their ligands by Northern blotting and in situ hybridization. Notch receptors and ligands were expressed in both proliferative and post-mitotic cells throughout adult rat gut, variously in epithelial, immune, and endothelial cells.

Expression of Notch1 and Jagged2 in the enteric nervous system.

The Notch signaling pathway is a vitally important pathway in regulating brain development. To explore the involvement of the Notch pathway in neuronal cells of adult rat gut, we investigated the expression of Notch1 and Jagged2 by in situ hybridization (ISH) and immunohistochemistry (IHC). In the enteric nervous system, Notch1 and Jagged2 were expressed in ganglia of the submucosal and myenteric plexus.