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Neurotensin—regulated miR-133α is involved in proinflammatory signalling in human colonic epithelial cells and in experimental colitis

OBJECTIVE: Neurotensin (NT) mediates colonic inflammation through its receptor neurotensin receptor 1 (NTR1). NT stimulates miR-133α expression in colonic epithelial cells. We investigated the role of miR-133α in NT-associated colonic inflammation in vitro and in vivo. DESIGN: miR-133α and aftiphili...

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Detalles Bibliográficos
Autores principales: Law, Ivy Ka Man, Bakirtzi, Kyriaki, Polytarchou, Christos, Oikonomopoulos, Angelos, Hommes, Daniel, Iliopoulos, Dimitrios, Pothoulakis, Charalabos
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BMJ Publishing Group 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4422787/
https://www.ncbi.nlm.nih.gov/pubmed/25112884
http://dx.doi.org/10.1136/gutjnl-2014-307329
Descripción
Sumario:OBJECTIVE: Neurotensin (NT) mediates colonic inflammation through its receptor neurotensin receptor 1 (NTR1). NT stimulates miR-133α expression in colonic epithelial cells. We investigated the role of miR-133α in NT-associated colonic inflammation in vitro and in vivo. DESIGN: miR-133α and aftiphilin (AFTPH) levels were measured by quantitative PCR. Antisense (as)-miR-133α was administrated intracolonicaly prior to induction of 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis and dextran sodium sulfate (DSS)-induced colitis. The effect of AFTPH was examined by gene silencing in vitro. RESULTS: NT increased miR-133α levels in NCM-460 overexpressing NTR1 (NCM460-NTR1) and HCT-116 cells. NT-induced p38, ERK1/2, c-Jun, and NF-κB activation, as well as IL-6, IL-8 and IL-1β messenger RNA (mRNA) expression in NCM-460-NTR1 cells were reduced in miR-133α-silenced cells, while overexpression of miR-133α reversed these effects. MiR-133α levels were increased in TNBS (2 day) and DSS (5 day) colitis, while NTR1 deficient DSS-exposed mice had reduced miR-133α levels, compared to wild-type colitic mice. Intracolonic as-miR-133α attenuated several parameters of colitis as well expression of proinflammatory mediators in the colonic mucosa. In silico search coupled with qPCR identified AFTPH as a downstream target of miR-133α, while NT decreased AFTPH expression in NCM-460-NTR1 colonocytes. Gene silencing of AFTPH enhanced NT-induced proinflammatory responses and AFTPH levels were downregulated in experimental colitis. Levels of miR-133α were significantly upregulated, while AFTPH levels were downregulated in colonic biopsies of patients with ulcerative colitis compared to controls. CONCLUSIONS: NT-associated colitis and inflammatory signalling are regulated by miR-133α-AFTPH interactions. Targeting of miR-133α or AFTPH may represent a novel therapeutic approach in inflammatory bowel disease.