MEDIATORS OF INFLAMMATION
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2016
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IF 3.418
Xin Liu,Ning Wang,Yuanfeng Zhu,Yongjun Yang,Xiaoli Chen,Shijun Fan,Qian Chen,Hong Zhou,Jiang Zheng
Activated macrophages are the primary sources of IL-12, a key cytokine bridging innate and adaptive immunity. However, macrophages produce low amounts of IL-12 upon stimulation and the underlying regulatory mechanism remains unclear. In this study, we found a new calcium-dependent mechanism that controlled IL-12 production in LPS-treated murine macrophages. First, LPS was demonstrated to induce extracellular calcium entry in murine peritoneal macrophages and inhibition of calcium influx resulted in marked enhancement in IL-12 production. Then, withdrawal of extracellular calcium was found to suppress CaMKK and AMPK activation triggered by LPS while chemical inhibition or genetic knockdown of these two kinases augmented LPS induced IL-12 production. AMPK activation increased the NAD+/NADH ratio and activated Sirtuin 1 (SIRT1), a NAD+-dependent deacetylating enzyme and negative regulator of inflammation. Chemical inhibitor or siRNA of SIRT1 enhanced IL-12 release while its agonist suppressed IL-12 production. Finally, it was found that SIRT1 selectively affected the transcriptional activity of NF-κB which thereby inhibited IL-12 production. Overall, our study demonstrates a new role of transmembrane calcium mobilization in immunity modulation such that inhibition of calcium influx leads to impaired activation of CaMKKβ-AMPK-SIRT1 signaling pathway which lifts restriction on NF-κB activation and results in enhanced IL-12 production.
研究领域:
免疫学
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细胞生物学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Biomaterials Science & Engineering
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2024
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IF 5.4
Yixiao Chen,Guoqing Li,Yufeng Ge,Su Liu,Jian Weng,Jianjing Lin,Ao Xiong,Hui Zeng,Xinbao Wu,Jun Yang,Fei Yu
In this study, we explore the cartilage defect repair mechanism by phosphocreatine-grafted chitosan hydrogels loaded with berberine-treated ATDC5 cells (CSMP@BBR@ATDC5). Under the optimal concentrations of LPS and BBR ideal conditions, ATDC5 cell toxicity and proliferation were detected with AM/PI and EdU staining. Additionally, qPCR and Western blot were employed to detect the expression of the SIRT1/BMP4 signaling pathway and chondrogenic-related factors in ATDC5 cells. Moreover, BBR-treated ATDC5 was seeded into a phosphocreatine-grafted chitosan hydrogel system. Subsequently, the cartilage defect was established in mice. After 4, 8, and 12 weeks, knee specimens were collected to evaluate the repair of cartilage defects. According to our findings, BBR can increase ATDC5 viability by LPS treatment. Likewise, it upregulates the SIRT1/BMP4 signaling pathway expression and chondrogenic-related factors. Another, it was shown by histological observation that the cartilage defect had been repaired more effectively in the CSMP@BBR@ATDC5 group than in the other groups. Finally, the expressions of chondrogenic-related factors and SIRT1/BMP4 signaling pathway were upregulates in CSMP@BBR@ATDC5 than in other groups. In vitro, BBR protects inflammatory ATDC5 cells and maintains the expression of chondrogenic-related factors. Subsequently, we successfully use CSMP@BBR@ATDC 5 to repair knee cartilage defects in mice.
研究领域:
组织工程
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再生医学
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骨科
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细胞生物学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2020
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IF 7.182
Yajuan Bai,Xuchao Jia,Fei Huang,Ruifen Zhang,Lihong Dong,Lei Liu,Mingwei Zhang
In this study, LPIIa, a purified polysaccharide from longan pulp, was isolated. Its anti-inflammatory activity and intestinal barrier protection were investigated with LPS-treated co-culture model of Caco-2 cells and RAW 264.7 macrophages. The average molecular weight LPIIa was 159.3 kDa. Its detailed structure was shown below. The backbone of LPIIa was composed of (1→3,4)-linked-α-Rha p , (1→4)-linked-β-Gal p , (1→6)-linked-β-Gal p , and (1→3,6)-linked-β-Gal p , with branches at the O-4 of Rha and O-3 of Gal, consisting of side chains of α-Ara f , β-Gal p , and α-Glc p . In LPS-induced RAW 264.7 macrophages, LPIIa suppressed the production of inflammatory mediators, including TNF-α, IL-6, NO, and PGE2, and inhibited iNOS and COX-2 gene expression. In addition, LPIIa attenuated intestinal tight-junctional channel protein Claudin-2 expression and increased tight-junctional barrier protein ZO-1 expression in Caco-2 cells. Knowing the structural features and activities of longan polysaccharide gives insights into longan polysaccharide application as an anti-inflammatory agent or adjuvant in curing the intestinal inflammation.
研究领域:
药理学
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免疫学
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胃肠病学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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