Tumor necrosis factor alpha increases epithelial barrier permeability by disrupting tight junctions in Caco-2 cells
Braz. j. med. biol. res
; 43(4): 330-337, Apr. 2010. ilus, graf
Article
en En
| LILACS
| ID: lil-543582
Biblioteca responsable:
BR1.1
ABSTRACT
The objectives of this study were to determine the effect of tumor necrosis factor alpha (TNF-á) on intestinal epithelial cell permeability and the expression of tight junction proteins. Caco-2 cells were plated onto Transwell® microporous filters and treated with TNF-á (10 or 100 ng/mL) for 0, 4, 8, 16, or 24 h. The transepithelial electrical resistance and the mucosal-to-serosal flux rates of the established paracellular marker Lucifer yellow were measured in filter-grown monolayers of Caco-2 intestinal cells. The localization and expression of the tight junction protein occludin were detected by immunofluorescence and Western blot analysis, respectively. SYBR-Green-based real-time PCR was used to measure the expression of occludin mRNA. TNF-á treatment produced concentration- and time-dependent decreases in Caco-2 transepithelial resistance and increases in transepithelial permeability to the paracellular marker Lucifer yellow. Western blot results indicated that TNF-á decreased the expression of phosphorylated occludin in detergent-insoluble fractions but did not affect the expression of non-phosphorylated occludin protein. Real-time RT-PCR data showed that TNF-á did not affect the expression of occludin mRNA. Taken together, our data demonstrate that TNF-á increases Caco-2 monolayer permeability, decreases occludin protein expression and disturbs intercellular junctions.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
LILACS
Asunto principal:
Permeabilidad de la Membrana Celular
/
Factor de Necrosis Tumoral alfa
/
Uniones Estrechas
/
Células Epiteliales
/
Mucosa Intestinal
/
Proteínas de la Membrana
Límite:
Humans
Idioma:
En
Revista:
Braz. j. med. biol. res
Asunto de la revista:
BIOLOGIA
/
MEDICINA
Año:
2010
Tipo del documento:
Article
País de afiliación:
China