Berberine, an isoquinoline alkaloid suppresses TXNIP mediated NLRP3 inflammasome activation in MSU crystal stimulated RAW 264.7 macrophages through the upregulation of Nrf2 transcription factor and alleviates MSU crystal induced inflammation in rats

2017 ◽  
Vol 44 ◽  
pp. 26-37 ◽  
Author(s):  
Palani Dinesh ◽  
MahaboobKhan Rasool
2021 ◽  
Vol 12 (10) ◽  
Author(s):  
Jie Zheng ◽  
Lu Yao ◽  
Yijing Zhou ◽  
Xiaoqun Gu ◽  
Can Wang ◽  
...  

AbstractAtopic dermatitis (AD) is a common chronic pruritic inflammatory skin disorder characterized by recurrent eczematous lesions. Interleukin (IL)−33, a cytokine of the IL-1 family, was found to play an important role in the pathogenesis of AD. As a key component of the inflammasome, NLRP3 has been mostly described in myeloid cells that to mediate inflammasome activation conducted proinflammatory cytokine production of the IL-1 family. However, the role of NLRP3 inflammasome in the pathogenesis of AD, as well as IL-33 processing are highly controversial. Whether NLRP3 can mediate IL-33 expression and secretion independently of the inflammasome in the epithelium of AD has remained unclear. In this article, we found the mRNA expression of Il33 and Nlrp3 were notably increased in the lesional skin of AD patients compared to healthy controls. We then found a significant positive correlation between the expression of Nlrp3 and Il33 in the epithelium of MC903-mediated AD mice model, but no changes were observed for Il36α, Il36γ, Il1β, or Il18 mRNA expression, as well as IL-1β or IL-18 production. Overexpression of NLRP3 in human immortalized epithelial cells increased IL-33 expression, whereas siRNA targeting NLRP3 abolished IL-33 expression. In addition, inhibition of NLRP3 inflammasome activation or caspase-1 activity with MCC950 or VX-765 showed no effect on the expression and secretion of IL-33 in AD mice. Unlike myeloid cells, NLRP3 predominantly located in the nucleus of epithelial cells, which could directly bind to Il33 specific-promoters and transactivate it through an interaction with transcription factor IRF4. Furthermore, NLRP3 deficient mice exhibited a significant alleviated epidermis inflammation and decreased mRNA expression and secretion of IL-33 in MC903-mediated AD mice without interfering with TSLP and IL-1β production. Our results demonstrate a novel ability of NLRP3 to function as a crucial transcription factor of IL-33 in epithelium independently of inflammasome that to mediate the pathological process of AD.


2020 ◽  
Author(s):  
Fengxia Guo ◽  
Bing Hu ◽  
Yanhua Sha ◽  
Kangning Zhu ◽  
Gang Li

Abstract BackgroundIncreasing evidence suggests that transcription factor EB (TFEB) inhibits inflammation in endothelial cell (ECs) and reduces development of atherosclerosis. However, little is known about the mechanism of action of TFEB on inflammation in atherosclerosis (AS).MethodsThe levels of TFEB, NLRP3, VCAM-1, ICAM-1, E-selectin, MCP-1, cleaved caspase-1, IL-1β and IL-18 in ECs were examined by immunoblotting, quantitative real time-polymerase chain reaction (qRT-PCR) , Enzyme-linked immunosorbent assay. The LDH activity were examined by LDH assay. TUNEL-positive cell were examined by TUNEL assay. The relationship between TFEB and NLRP3 were examined by immunofluorescence and coimmunoprecipitation. The effects of TFEB on atherosclerotic lesions by hematoxylin and eosin, TUNEL and collagen staining in the aortic valve of ApoE-/- mice fed a high fat diet (HFD).ResultsHere, we report that H2O2-induced cell pyroptosis and inflammatory response were mainly due to nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome activation. The nuclear protein TFEB was significantly increased by H2O2, and knockdown of TFEB aggravated cell pyroptosis and inflammatory response. TFEB directly bound to NLRP3 and blocked NLRP3-mediated cell pyroptosis and inflammatory response. The effect of H2O2 on TFEB might be associated with AMP-activated protein kinase/mechanistic target of rapamycin-dependent signaling pathways.ConclusionsOur findings indicated that a novel TFEB–NLRP3 axis was a critical regulator in EC pyroptosis and inflammation, which could be potential therapeutic targets in AS and related cardiovascular diseases.


FEBS Letters ◽  
2014 ◽  
Vol 588 (23) ◽  
pp. 4513-4519 ◽  
Author(s):  
Liuluan Zhu ◽  
Qingcai Meng ◽  
Shuntao Liang ◽  
Yaluan Ma ◽  
Rui Li ◽  
...  

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