NOD2表达降低通过抑制氧化应激改善肥胖小鼠心肌缺血/再灌注损伤

    Reduced NOD2 expression alleviates myocardial ischemia/reperfusion injury in obese mice by inhibiting oxidative stress

      摘要
    • 摘要:
      目的 旨在明确NOD2在高脂饮食诱导的肥胖小鼠心肌缺血/再灌注损伤中的作用及其潜在机制。
      方法 特异性敲低小鼠心脏组织中NOD2表达，建立肥胖合并心肌缺血/再灌注损伤模型，并构建NOD2敲低的缺氧/复氧心肌细胞（H9c2）模型。通过RT-PCR技术、免疫印迹技术检测各实验组中小鼠心肌NOD2的mRNA及蛋白表达水平；通过TTC染色评估心脏梗死面积；通过检测试剂盒检测各实验组小鼠血清中cTnI、CK-MB、LDH含量；通过免疫印迹技术检测凋亡相关蛋白（Bax、Bcl-2、caspase-3剪切体），通过流式细胞术检测H9c2细胞凋亡情况；通过检测试剂盒检测MDA和SOD的水平、使用共聚焦显微镜观察H9c2心肌细胞中ROS水平。
      结果 转录组公共数据集分析显示，NOD2是心肌缺血/再灌注损伤和高脂饮食诱导的肥胖小鼠心脏组织中显著上调的共同分子。在心肌缺血/再灌注损伤小鼠心脏组织中进一步证实，NOD2的mRNA和蛋白水平显著升高（P<0.01），高脂饮食诱导的肥胖状态进一步增加了缺血/再灌注损伤后NOD2的表达水平（P<0.01）。心脏特异性敲低NOD2显著降低肥胖小鼠心肌梗死面积及血清cTnI、CK-MB、LDH水平（P<0.01），凋亡相关蛋白Bcl2与Bax的比值显著上调（P<0.01），caspase-3剪切体的表达减少（P<0.01）。此外，敲低H9c2细胞中的NOD2显著抑制了缺氧/复氧诱导的细胞凋亡，降低了ROS水平及MDA含量（P<0.01），同时显著提高了SOD活性（P<0.01）。
      结论 NOD2是促进心肌缺血/再灌注损伤的关键分子，敲低NOD2可以改善肥胖小鼠心肌缺血/再灌注损伤，其作用机制可能与心肌细胞内ROS水平的降低密切相关。本研究为肥胖合并心肌缺血/再灌注损伤的临床治疗提供了新的科学依据与研究思路。

       

      Abstract:
      AIM  To investigate the role of NOD2 in high-fat diet-induced myocardial ischemia/reperfusion (MI/R) injury in obese mice, and explore its underlying mechanism.
      METHODS  Cardiac-specific NOD2 knockdown was performed in mice. A model of obesity with MI/R injury was established, and a hypoxia/reoxygenation (H/R) cardiomyocyte (H9c2) model with NOD2 knockdown was also developed. The mRNA and protein expression levels of NOD2 in myocardial tissue were assessed via RT-PCR and Western blotting. Myocardial infarction area was evaluated using TTC staining, and serum levels of cTnI, CK-MB, and LDH were measured using detection kits. Apoptosis-related proteins (Bax, Bcl-2, caspase-3) were analyzed by Western blotting, and H9c2 cell apoptosis was quantified using flow cytometry. Oxidative stress markers (MDA, SOD, ROS) were measured using assay kits and confocal microscopy.
      RESULTS  Transcriptome analysis of public datasets revealed significant upregulation of NOD2 in heart tissues from both MI/R injury and high-fat diet-induced obesity models. In mice with MI/R injury, the mRNA and protein levels of NOD2 were significantly increased (P<0.01), and this increase was further amplified in the obesity model (P<0.01). Cardiac-specific NOD2 knockdown significantly reduced myocardial infarction area and serum levels of cTnI, CK-MB, and LDH in obese mice (P<0.01). Additionally, the Bcl-2/Bax ratio was significantly upregulated (P<0.01), and caspase-3 expression was reduced (P<0.01). In H9c2 cells, NOD2 knockdown significantly inhibited H/R-induced apoptosis, decreased ROS and MDA levels (P<0.01), and increased SOD activity (P<0.01).
      CONCLUSION  NOD2 is a key regulator of MI/R injury. Knockdown of NOD2 alleviates MI/R injury in obese mice, and its underlying mechanism may be closely related to the decrease of reactive oxygen species (ROS) levels in cardiomyocytes. This study provides new insights and a foundation for clinical treatment of obesity-related MI/R injury.

       

      • HTML全文
      • 参考文献(21)
      • 相关文章
      • 施引文献
    • 资源附件(0)

    /

    返回文章
    返回