CRP-Induced NLRP3 Inflammasome Activation Increases LDL Transcytosis Across Endothelial Cells
CRP-Induced NLRP3 Inflammasome Activation Increases LDL Transcytosis Across Endothelial Cells
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CRP 诱导的 NLRP3 炎症小体激活增加 LDL 跨内皮细胞的转胞吞作用
DOI：
10.3389/fphar.2019.00040
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发表时间：
2019-01-30
影响因子：
5.6
通讯作者：
Jin, Si
中科院分区：
文献类型：
--
作者：
Bian, Fang;Yang, Xiao-Yan;Jin, Si
NLRP 3炎性小体是一种多蛋白质胞质复合物，可激活IL-1家族细胞因子，在动脉粥样硬化（AS）中发挥重要作用。高敏C反应蛋白（hs-CRP）被广泛认为是一个主要的心血管风险预测因子，最近的研究将NLRP 3命名为CRP水平的预测因子。越来越多的证据表明，载脂蛋白B100的脂蛋白，如低密度脂蛋白（LDL）的内皮下滞留是动脉粥样硬化形成的最初步骤，通常被称为“响应保留假说”。我们以前报道过CRP通过直接增加LDL穿过内皮细胞（EC）的胞吞作用促进AS。本研究旨在探讨CRP对NLRP 3炎性小体激活的影响以及NLRP 3炎性小体在CRP诱导的LDL转胞吞中的作用。我们发现CRP可上调NF-κB活性，NF-κB抑制剂（BAY-11-7082）和Fcγ受体（FcγRs）抑制剂（CD 32/64 Ab）可阻断CRP诱导的NF-κB活化。CRP还诱导pro-IL-1β和NLRP 3的表达，而BAY和CD 32/64 Ab抑制CRP介导的NLRP 3和pro-IL-1β的表达。此外，CRP激活EC中的NLRP 3炎性体。NADPH氧化酶抑制剂二亚苯基碘鎓（DPI）和二硫苏糖醇（DTT）、广谱P2受体抑制剂氧化ATP（oATP）和半胱氨酸蛋白酶的广谱抑制剂E-64 d可抑制CRP诱导的NLRP 3炎性小体激活。此外，NLRP 3 siRNA和caspase-1抑制剂阻断CRP介导的LDL跨EC的胞吞转运。总之，NLRP 3炎性体激活被证明参与CRP介导的LDL跨EC的转胞吞作用。CRP不仅通过FcγRs/NF-κB途径增加pro-IL-1β和NLRP 3的表达，而且通过上调活性氧（ROS）水平、嘌呤能受体信号传导和半胱氨酸蛋白酶的活化促进NLRP 3炎性小体活化和IL-1β成熟。
The NLRP3 inflammasome, a multiprotein cytosolic complex that activates the IL-1 family of cytokines, plays an important role in atherosclerosis (AS). High-sensitivity c-reactive protein (hs-CRP) is widely recognized as a major cardiovascular risk predictor and recent studies name NLRP3 as a predictor of CRP levels. Mounting evidence has indicated that subendothelial retention of apolipoprotein B100-containing lipoproteins, such as low-density lipoprotein (LDL), is the initial step of atherogenesis, and is usually termed the “response to retention hypothesis.” We previously reported that CRP promotes AS by directly increasing LDL transcytosis across endothelial cells (ECs). The present study aims to investigate the effects of CRP on NLRP3 inflammasome activation and the role of the NLRP3 inflammasome in CRP-induced LDL transcytosis. We found that CRP upregulated NF-κB activity, the NF-κB inhibitor (BAY-11-7082) and Fcγ receptors (FcγRs) inhibitor (CD32/64Ab) blocked CRP-induced NF-κB activation. CRP also induced expression of pro-IL-1β and NLRP3, while BAY and CD32/64 Ab suppressed CRP-mediated expression of NLRP3 and pro-IL-1β. Moreover, CRP activated the NLRP3 inflammasome in ECs. NADPH oxidase inhibitor, diphenylene iodonium (DPI) and dithiothreitol (DTT), a broad-spectrum P2 receptor inhibitor, oxidized ATP (oATP), and a broad inhibitor of cysteine proteases, E-64d, inhibited CRP-induced NLRP3 inflammasome activation. Furthermore, NLRP3 siRNA and caspase-1 inhibitor blocked CRP-mediated LDL transcytosis across ECs. In conclusion, NLRP3 inflammasome activation was shown to be involved in CRP-mediated LDL transcytosis across ECs. CRP not only increased the expression of pro-IL-1β and NLRP3 via the FcγRs/NF-κB pathway, but also promoted NLRP3 inflammasome activation and IL-1β maturation by upregulation of reactive oxygen species (ROS) levels, purinergic receptor signaling, and activation of cysteine proteases.