Bromodomain-containing protein 4 inhibition alleviates matrix degradation by enhancing autophagy and suppressing NLRP3 inflammasome activity in NP cells.
J Cell Physiol
; 235(7-8): 5736-5749, 2020 07.
Article
en En
| MEDLINE
| ID: mdl-31975410
ABSTRACT
An imbalance between matrix synthesis and degradation is the hallmark of intervertebral disc degeneration while inflammatory cytokines contribute to the imbalance. Bromodomain and extra-terminal domain (BET) family is associated with the pathogenesis of inflammation, and inhibition of BRD4, a vital member of BET family, plays an anti-inflammatory role in many diseases. However, it remains elusive whether BRD4 plays a similar role in nucleus pulposus (NP) cells and participates in the pathogenesis of intervertebral disc degeneration. The present study aims to observe whether BRD4 inhibition regulates matrix metabolism by controlling autophagy and NLRP3 inflammasome activity. Besides, the relationship was investigated among nuclear factor κB (NF-κB) signaling, autophagy and NLRP3 inflammasome in NP cells. Here, real-time polymerase chain reaction, western blot analysis and adenoviral GFP-LC3 vector transduction in vitro were used, and it was revealed that BRD4 inhibition alleviated the matrix degradation and increased autophagy in the presence or absence of tumor necrosis factor α. Moreover, p65 knockdown or treatment with JQ1 and Bay11-7082 demonstrated that BRD4 inhibition attenuated NLRP3 inflammasome activity through NF-κB signaling, while autophagy inhibition by bafilomycin A1 promoted matrix degradation and NLRP3 inflammasome activity in NP cells. In addition, analysis of BRD4 messenger RNA expression in human NP tissues further verified the destructive function of BRD4. Simply, BRD4 inhibition alleviates matrix degradation by enhancing autophagy and suppressing NLRP3 inflammasome activity through NF-κB signaling in NP cells.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Factores de Transcripción
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Proteínas Nucleares
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Factor de Transcripción ReIA
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Degeneración del Disco Intervertebral
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Proteína con Dominio Pirina 3 de la Familia NLR
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Inflamación
Tipo de estudio:
Prognostic_studies
Límite:
Animals
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Humans
Idioma:
En
Año:
2020
Tipo del documento:
Article