IL-1beta-induced apoptosis in rat gastric enterochromaffin-like cells is mediated by iNOS, NF-kappaB, and Bax protein.
Gastroenterology
; 118(3): 515-24, 2000 Mar.
Article
en En
| MEDLINE
| ID: mdl-10702202
ABSTRACT
BACKGROUND & AIMS:
Enterochromaffin-like (ECL) cells are histamine-containing endocrine cells in the gastric mucosa. Previous studies have shown that the proinflammatory cytokine interleukin (IL)-1beta present during chronic gastritis inhibits histamine synthesis in ECL cells and leads to sustained functional impairment. This study investigated the effects of IL-1beta on ECL cell apoptosis and the related signal-transduction mechanisms.METHODS:
ECL cells were isolated by pronase digestion and a combination of elutriation, gradient centrifugation, and 48-hour culture (purity >/=90%). Apoptosis was measured by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling reaction and cell death detection enzyme-linked immunosorbent assay.RESULTS:
IL-1beta (100 pg/mL) increased the rate of programmed cell death 2-3 fold in ECL cells after 24 hours of incubation (total of 12%-14%). This effect was completely inhibited by the NF-kappaB inhibitor, proteasome inhibitor I, and the nitric oxide synthase inhibitor (iNOS) N(G)-monomethyl-L-arginine (10(-4) mol/L), but not by the caspase 3 inhibitor, Asp-Glu-Val-Asp-CHO. Western blot analysis, reverse-transcription polymerase chain reaction (PCR), and in situ PCR showed that IL-1beta induced gene expression (after 2-4 hours) and protein synthesis (6-18 hours) of the iNOS isoform in ECL cells. Bax protein expression was increased in response to IL-1beta. In contrast, bcl-2 gene expression was increased in response to basic fibroblast growth factor, which has been shown to counteract IL-1beta- induced apoptosis.CONCLUSIONS:
These data suggest that IL-1beta induces programmed cell death in isolated rat ECL cells via activation of NF-kappaB, iNOS, and the Bax protein.
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Banco de datos:
MEDLINE
Asunto principal:
FN-kappa B
/
Proteínas Proto-Oncogénicas
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Interleucina-1
/
Apoptosis
/
Óxido Nítrico Sintasa
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Proteínas Proto-Oncogénicas c-bcl-2
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Células Enterocromafines
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Mucosa Gástrica
Límite:
Animals
Idioma:
En
Año:
2000
Tipo del documento:
Article