Wiger Christine W, Ranheim Trine, Arnesen Henriette, Vaage Jarle, Pischke Søren E, Yndestad Arne, Stensløkken Kåre-Olav, Torp May-Kristin
Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
Research Institute of Internal Medicine, Oslo University Hospital, Oslo, Norway.
Immun Inflamm Dis. 2025 Jan;13(1):e70133. doi: 10.1002/iid3.70133.
Sepsis is associated with myocardial injury and early mortality. The innate immune receptor Toll-like receptor 4 (TLR4) can recognize pathogen-associated-molecular-patterns (PAMPs) and damage-associated molecular patterns (DAMPs); the latter are released during tissue injury. We hypothesized that TLR4 inhibition reduces proinflammatory signaling and cytokine release in: (1) LPS or Escherichia coli-treated isolated mouse heart; (2) LPS-treated mouse primary adult cardiomyocytes; and (3) the isolated heart during ischemia-reperfusion.
Isolated C57BL/6N male mouse hearts were perfused for 120 min, with either LPS, E. coli, with and without CLI-095 (TLR4 inhibitor). Primary adult mouse cardiomyocytes were treated with LPS or LPS + CLI-095. Isolated hearts, exposed to 35 min of global ischemia, were treated with either vehicle or CLI-095 during reperfusion. Infarct size was quantified by triphenyltetrazolium staining. Cytokine expression was analyzed with ELISA, western blot analysis, and qPCR.
In isolated hearts, E. coli increased the expression of proinflammatory cytokines (IL-6 and CXCL2), which was not attenuated with TLR4 inhibition. TLR4 inhibition reduced expression (p = 0.004) and release of IL-6 (p < 0.0001) in LPS-exposed isolated hearts. LPS activated the nuclear-factor κ-light-chain-enhancer of activated B cells signaling pathway (NF-κB) in primary adult cardiomyocytes. Moreover, TLR4 inhibition reduced LPS-induced mRNA expression and release of IL-6 in primary adult cardiomyocytes. Isolated hearts treated with CLI-095 during reperfusion after ischemia (induced DAMPs release) showed reduced infarct size (39 ± 17% to 26 ± 8%, p = 0.034) and decreased IL-6 release (p = 0.006).
Inhibition of TLR4 reduced proinflammatory signaling and cytokine release in LPS-treated and ischemia-reperfused isolated mouse hearts and in primary adult murine cardiomyocytes.
脓毒症与心肌损伤和早期死亡率相关。天然免疫受体Toll样受体4（TLR4）可识别病原体相关分子模式（PAMP）和损伤相关分子模式（DAMP）；后者在组织损伤时释放。我们假设TLR4抑制可减少以下情况中的促炎信号传导和细胞因子释放：（1）脂多糖（LPS）或大肠杆菌处理的离体小鼠心脏；（2）LPS处理的成年小鼠原代心肌细胞；以及（3）缺血再灌注期间的离体心脏。
将离体的C57BL/6N雄性小鼠心脏灌注120分钟，分别用LPS、大肠杆菌处理，同时使用或不使用CLI-095（TLR4抑制剂）。成年小鼠原代心肌细胞用LPS或LPS + CLI-095处理。暴露于35分钟全心缺血的离体心脏在再灌注期间用赋形剂或CLI-095处理。通过三苯基四氮唑染色定量梗死面积。用酶联免疫吸附测定（ELISA）、蛋白质免疫印迹分析和实时定量聚合酶链反应（qPCR）分析细胞因子表达。
在离体心脏中，大肠杆菌增加了促炎细胞因子（白细胞介素-6（IL-6）和CXC趋化因子配体2（CXCL2））的表达，而TLR4抑制并未减弱这种表达。TLR4抑制降低了LPS处理的离体心脏中IL-6的表达（p = 0.004）和释放（p < 0.0001）。LPS激活了成年小鼠原代心肌细胞中的核因子κB轻链增强子（NF-κB）信号通路。此外，TLR4抑制降低了LPS诱导的成年小鼠原代心肌细胞中IL-6的mRNA表达和释放。缺血（诱导DAMP释放）后再灌注期间用CLI-095处理的离体心脏显示梗死面积减小（从39±17%降至26±8%，p = 0.034），IL-6释放减少（p = 0.006）。
TLR4抑制减少了LPS处理和缺血再灌注的离体小鼠心脏以及成年小鼠原代心肌细胞中的促炎信号传导和细胞因子释放。
