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本研究旨在评估MAPK信号通路在梗死后心力衰竭期间调节心肌细胞凋亡中的作用及其可能的潜在机制。通过左前降支冠状动脉闭塞诱发构建梗死后心力衰竭的小鼠模型,通过组织化学和ELISA分别测定血清中心肌梗死面积和肌酸激酶-MB(CK-MB)和心肌肌钙蛋白(c Tn I)水平。此外,评估了氧-葡萄糖剥夺/恢复(OGD/R)对具有和不具有MAPK抑制剂PD-98059预处理的心肌细胞的直接细胞毒性作用。分别采用MTT、ELISA和流式细胞术测定PD-98059对细胞活力、乳酸脱氢酶(LDH)释放和细胞凋亡的影响。采用RT-PCR和Western blotting检测内质网(ER)应激标志物如葡萄糖调节蛋白78、CCAAT/增强子结合蛋白同源蛋白和切割的半胱天冬酶-12的表达。我们发现,MAPK抑制剂PD-98059显著降低心肌梗死面积、血清CK-MB和c Tn I水平;PD-98059预处理显著提高了OGD/R细胞活力的恢复和细胞凋亡的降低(p<0.05)。此外,PD-98059预处理可显着降低葡萄糖调节蛋白78,CCAAT/增强子结合蛋白同源蛋白,并在m RNA水平和蛋白水平上切割caspase-12表达(p<0.05)。这一研究表明,MAPK信号通路在通过抑制内质网应激调节心肌细胞凋亡中起着重要作用。
This study was designed to evaluate the role of MAPK signaling in the regulation of cardiomyocyte apoptosis during post-infarction heart failure and its possible underlying mechanisms. A mouse model of post-infarction heart failure induced by left anterior descending coronary artery occlusion was established. Serum myocardial infarct size, creatine kinase-MB (CK-MB) and cardiac troponin I (cTn I )Level. In addition, direct cytotoxic effects of oxygen-glucose deprivation / recovery (OGD / R) on cardiomyocytes with and without the MAPK inhibitor PD-98059 preconditioning were evaluated. The effects of PD-98059 on cell viability, lactate dehydrogenase (LDH) release and apoptosis were determined by MTT, ELISA and flow cytometry respectively. The expression of endoplasmic reticulum (ER) stress markers such as glucose regulatory protein 78, CCAAT / enhancer binding protein homolog and cleaved caspase-12 were detected by RT-PCR and Western blotting. We found that the MAPK inhibitor PD-98059 significantly reduced myocardial infarct size, serum CK-MB and cTn I levels; PD-98059 pretreatment significantly increased the recovery of OGD / R cell viability and decreased apoptosis (p <0.05 ). In addition, pretreatment with PD-98059 significantly reduced the expression of glucose regulatory protein 78, CCAAT / enhancer binding protein homologues and cleaved caspase-12 protein at mRNA and protein levels (p <0.05). This study shows that MAPK signaling plays an important role in the regulation of cardiomyocyte apoptosis by inhibiting endoplasmic reticulum stress.