The non-canonical NF-κB pathway is induced by cytokines in pancreatic beta cells and contributes to cell death and proinflammatory responses in vitro.
Diabetologia
; 59(3): 512-21, 2016 Mar.
Article
em En
| MEDLINE
| ID: mdl-26634571
ABSTRACT
AIMS/HYPOTHESIS:
Activation of the transcription factor nuclear factor (NF)-κB by proinflammatory cytokines plays an important role in beta cell demise in type 1 diabetes. Two main signalling pathways are known to activate NF-κB, namely the canonical and the non-canonical pathways. Up to now, studies on the role of NF-κB activation in beta cells have focused on the canonical pathway. The aim of this study was to investigate whether cytokines activate the non-canonical pathway in beta cells, how this pathway is regulated and the consequences of its activation on beta cell fate.METHODS:
NF-κB signalling was analysed by immunoblotting, promoter reporter assays and real-time RT-PCR, after knockdown or overexpression of key genes/proteins. INS-1E cells, FACS-purified rat beta cells and the human beta cell line EndoC-ßH1 exposed to cytokines were used as models.RESULTS:
IL-1ß plus IFN-γ induced stabilisation of NF-κB-inducing kinase and increased the expression and cleavage of p100 protein, culminating in the nuclear translocation of p52, the hallmark of the non-canonical signalling. This activation relied on different crosstalks between the canonical and non-canonical pathways, some of which were beta cell specific. Importantly, cytokine-mediated activation of the non-canonical pathway controlled the expression of 'late' NF-κB-dependent genes, regulating both pro-apoptotic and inflammatory responses, which are implicated in beta cell loss in early type 1 diabetes. CONCLUSIONS/INTERPRETATION:
The atypical activation of the non-canonical NF-κB pathway by proinflammatory cytokines constitutes a novel 'feed-forward' mechanism that contributes to the particularly pro-apoptotic effect of NF-κB in beta cells.Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Citocinas
/
NF-kappa B
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Células Secretoras de Insulina
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Humans
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Male
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article