Zhang Wenbo, Tao Aibin, Lan Ting, Cepinskas Gediminas, Kao Raymond, Martin Claudio M, Rui Tao
Division of Cardiology, Department of Medicine, The Affiliated People's Hospital of Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China.
Critical Illness Research, Lawson Health Research Institute, 800 Commissioners Road E., VRL Rm A6-138, London, ON, N6A 4G5, Canada.
Basic Res Cardiol. 2017 Mar;112(2):16. doi: 10.1007/s00395-017-0603-8. Epub 2017 Feb 6.
The NLRP3 inflammasome is an intracellular multiple-protein complex that controls the maturation and release of interleukin (IL)-1β and IL-18. Endogenous carbon monoxide (CO) is anti-inflammatory. The aim of this study was to assess the effects/mechanisms of CO-releasing molecule-3 (CORM-3)-dependent modulation of the NLRP3 inflammasome in cardiac fibroblasts (CF) and its effect on myocardial function in sepsis. CF were treated with CORM-3 or inactive CORM-3 (iCORM-3) before NLRP3 inflammasome priming with lipopolysaccharides (LPS) or following activation with adenosine triphosphate (ATP). In parallel, cardiomyocytes (CM) were challenged with supernatants of LPS/ATP-stimulated CF or a cytokine mixture (Cyto-mix) containing IL-1β, IL-18, and HMGB1. In vivo, mice were treated with CORM-3 before or after LPS to induce sepsis (endotoxemia). Pretreatment of CF with CORM-3 prevented an LPS-induced increase in NLRP3 and pro-IL-1β expression. Treatment of CF with CORM-3 before ATP prevented ATP-induced activation of the NLRP3 inflammasome. Challenging CF with LPS/ATP promoted NLRP3 interactions with adaptor ASC (apoptosis-associated speck-like protein containing a caspase-recruitment domain), which was prevented by CORM-3. Challenging CM with supernatants of CF with LPS/ATP or Cyto-mix (IL-1β, IL-18, and HMGB1) resulted in CM apoptosis, which was attenuated with either a CORM-3 or IL-1 receptor antagonist. Finally, myocardial NLRP3 inflammasome activation and myocardial dysfunction in septic mice were abolished by CORM-3. In NLRP3-deficient mice with sepsis, CORM-3 did not show additional benefits in improving myocardial function. Our results indicate that CORM-3 suppresses NLRP3 inflammasome activation by blocking NLRP3 interactions with the adaptor protein ASC and attenuates myocardial dysfunction in mice with sepsis.
NLRP3炎性小体是一种细胞内多蛋白复合物，可控制白细胞介素（IL）-1β和IL-18的成熟与释放。内源性一氧化碳（CO）具有抗炎作用。本研究旨在评估一氧化碳释放分子-3（CORM-3）对心脏成纤维细胞（CF）中NLRP3炎性小体的调节作用/机制及其对脓毒症心肌功能的影响。在用脂多糖（LPS）启动NLRP3炎性小体之前或用三磷酸腺苷（ATP）激活之后，用CORM-3或无活性的CORM-3（iCORM-3）处理CF。同时，用LPS/ATP刺激的CF的上清液或含有IL-1β、IL-18和高迁移率族蛋白B1（HMGB1）的细胞因子混合物（细胞因子混合物）刺激心肌细胞（CM）。在体内，在LPS诱导脓毒症（内毒素血症）之前或之后用CORM-3处理小鼠。用CORM-3预处理CF可防止LPS诱导的NLRP3和前IL-1β表达增加。在ATP之前用CORM-3处理CF可防止ATP诱导的NLRP3炎性小体激活。用LPS/ATP刺激CF可促进NLRP3与衔接蛋白ASC（含半胱天冬酶招募结构域的凋亡相关斑点样蛋白）的相互作用，而CORM-3可阻止这种相互作用。用LPS/ATP刺激的CF的上清液或细胞因子混合物（IL-1β、IL-18和HMGB1）刺激CM会导致CM凋亡，而CORM-3或IL-1受体拮抗剂可减轻这种凋亡。最后，CORM-3消除了脓毒症小鼠心肌NLRP3炎性小体的激活和心肌功能障碍。在患有脓毒症的NLRP3缺陷小鼠中，CORM-3在改善心肌功能方面未显示出额外益处。我们的结果表明，CORM-3通过阻断NLRP3与衔接蛋白ASC的相互作用来抑制NLRP3炎性小体的激活，并减轻脓毒症小鼠的心肌功能障碍。
