Cellular and Molecular Gastroenterology and Hepatology
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2024
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IF 7.1
Liang Wang,Jinsong Li,Mingshan Jiang,Yue Luo,Xiaoke Xu,Juan Li,Yang Pan,Hu Zhang,Zhi-Xiong Jim Xiao,Yang Wang
Background and Aims Dysfunction of the intestinal epithelial barrier comprising the junctional complex of tight junctions and adherent junctions leads to increased intestinal permeability, which is a major cause of uncontrolled inflammation related to Inflammatory Bowel Disease (IBD). The NAD + -dependent deacetylase SIRT1 is implicated in inflammation and the pathological process of IBD. We aimed to elucidate the protective role and underlying mechanism of SIRT1 in cell-cell junction and intestinal epithelial integrity. Methods The correlation of SIRT1 expression and human IBD was analyzed by GEO or immunohistochemical analyses. BK5.mSIRT1 transgenic mice and WT mice were given dextran sodium sulfate (DSS) and the manifestation of colitis-related phenotypes were analyzed. Intestinal permeability was measured by FITC-Dextran and cytokines expression was analyzed by QPCR. The expression of the cell junction-related proteins in DSS-treated or SIRT1-knockdown Caco2 or HCT116 cells was analyzed by Western blotting. The effects of Nicotinamide mononucleotide (NMN) in DSS-induced mice colitis were investigated. Correlations of the SIRT1-β-TrCP1-Snail1-Occludin/Claudin-1/E-cadherin pathway with human IBD samples were analyzed. Results Reduced SIRT1 expression is associated with human IBD specimens. SIRT1 transgenic mice exhibit much-reduced manifestations of DSS-induced colitis. the activation of SIRT1 by NMN bolsters intestinal epithelial barrier function and ameliorates DSS-induced colitis in mice. Mechanistically, DSS down-regulates SiRT1 expression, leading to destabilization of β-TrCP1 and upregulation of Snail1, accompanied by reduced expression of E-cadherin, Occludin, and Claudin-1, consequently resulting in increased epithelial permeability and inflammation. The deregulated SIRT1-β-TrCP1-Snail1-Occludin/Claudin-1/E-cadherin pathway correlates with human IBD. Conclusion SIRT1 is pivotal in maintaining the intestinal epithelial barrier integrity via modulation of the β-TrCP1-Snail1-E-cadhein/Occludin/Claudin-1 pathway.
研究领域:
胃肠病学
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免疫学
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分子生物学
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细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
CELL DEATH AND DIFFERENTIATION
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2025
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IF 15.4
Zeng Ke,Zhu Yuqi,Han Zhongxin,Xiong Siyi,Zhao Yan,Xiao Zilong,Xie Yingchao,Jin Shiyu,Dong Tingru,Lan Lan,Liu Weiwei,Du Yongzhong,Guan Cuiping,Yu Xiao,Song Xiuzu
NLRP3 functions as a critical intracellular danger sensor for inflammasome activation, playing a crucial role in autoimmune diseases. Vitiligo progression has been linked to NLRP3, yet its specific involvement in melanocytes of vitiligo remains poorly understood. In this study, we demonstrate that NLRP3 expression is significantly upregulated in the melanocytes of vitiligo patients and melanoma-Treg-induced vitiligo mouse model. Genetic knockout of NLRP3 effectively alleviates vitiligo progression in these mice. Our mechanistic investigations reveal that the downregulation of the E3 ligase β-TrCP1 in vitiligo melanocytes decreases K27-linked ubiquitination levels of NLRP3, which in turn weakens its interaction with the autophagy receptor NDP52. This disruption impairs the selective autophagic degradation of NLRP3, leading to hyperactivation of inflammation and pyroptosis in melanocytes, thereby accelerating vitiligo pathogenesis. Notably, melanocyte-specific knockdown of NLRP3 using lysine-proline-valine (KPV)-modified deformable liposomes (KPV-Lipos) carrying Nlrp3 shRNA significantly alleviates vitiligo development. This study elucidates the mechanism by which autophagy dysfunction mediated excessive NLRP3 inflammasome activation in melanocytes contributes to vitiligo pathogenesis, highlighting potential therapeutic strategies targeting these pathways for the treatment of vitiligo and other pigment-related skin diseases. Overview of disrupted NLRP3 autophagic degradation in vitiligo melanocytes . In healthy melanocytes, NLRP3 expression is upregulated when subjected to oxidative stress, along with an increase in the E3 ligase β-TrCP1, which enhances the K27-linked ubiquitination of NLRP3 and further strengthens its binding to the autophagy receptor protein NDP52, thus effectively suppressing the excessive inflammatory response. Whereas in the melanocytes of vitiligo patients, decreased expression of β-TrCP1 leads to downregulation of K27-linked ubiquitination in NLRP3, thus inhibiting its autophagic degradation. The persistent activation of NLRP3 in vitiligo melanocytes promotes the cleavage of pro-IL-1β and GSDMD. GSDMD-N subsequently forms pores on the cell membrane, which causes the release of IL-1β and results in melanocyte pyroptosis. In our study, we utilize KPV-Lipos with Nlrp3 shRNA to precisely knockdown NLRP3 expression in melanocytes and effectively alleviate vitiligo development, which provide a potentially promising strategy for the treatment of vitiligo. MC, melanocytes.
研究领域:
皮肤病学
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免疫学
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细胞生物学
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自身免疫性疾病
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子