氧化低密度脂蛋白诱导心肌炎反应的研究

Effects of oxidized low-density lipoprotein on inflammation in cultured cardiomyocytes

目的探讨氧化低密度脂蛋白（ox-LDL）对乳鼠心肌细胞炎症反应的影响。方法原代培养乳鼠心肌细胞，用不同浓度的ox-LDL干预24小时和同一浓度ox-LDL干预24～72小时。用RT-PCR、免疫细胞化学染色，观察ox-LDL对细胞PPAR-ymRNA和TNF-amRNA的表达、NF_KB活化的影响。结果ox-LDL可诱导心肌细胞TNF_amRNA表达及NF-KB活化，并可抑制PPAR—ymRN表达，与对照组比较有显著性差异性（P〈0．05）。BSA组与空白对照组比较差异无显著（P〉0．05）。随着ox-LDL浓度和时间的增加，各ox-LDL组间比较有显著差异（P〈0．05）。结论ox-LDL能上调心肌细胞TNF-amRNA及NF-κB活化，并可抑制PPAR-γmRN袁达，提示ox-LDL在糖尿病心肌病的发生中可能具有重要的作用。

AIM To investigate the effects of oxidized low-density lipoprotein on inflammation in cultured rat cardiomyocytes. Methods Primary cardiomyocytes were isolated from Sprague-Dawley neonatal （1 to 2 days old） rats ven- tricles. Neonatal rat ventricular myocytes were exposed to ox-LDL for 24 to 72 hours. PPARymRNA and TNF-amRNA expressions were determined by RT-PCR. Activation of NF-κB in the cells was examined with immunocytochemistry. Results Ox-LDL induced the expression of TNF-α mRNA and the activation of NF-xB increased. The expression of PPAR7 mRNA decreased, compared with control group （P〈0.05）. The differences among different ox-LDL groups were significant （P〈0.05）. Conclusion ox-LDL significantly increased TNF-α mRNA expression and NF-κB activation and restrain the expression of PPARγ mRNA. These data suggest that ox-LDL play an important role in the onset of diabetic cardiomyopathy.