缺血后适应中心肌营养素1对心肌细胞的保护作用研究

目的探讨心肌营养素1（CT-1）在缺血后适应中对心肌细胞的保护作用机制及参与的信号通路。方法选择H9C2乳鼠心肌细胞株．实验分为对照组、缺氧复氧组、缺氧后适应组、缺氧后适应＋cT_1组、缺氧后适应＋CT—1＋Akt阻断剂组、缺氧后适应＋CT-1＋二甲基亚砜组，MTS法检测细胞的存活率，流式细胞仪检测细胞的凋亡率，Western—blot检测Akt蛋白表达，Q．PCR检测BadmRNA的表达。结果缺氧复氧组较对照组细胞凋亡率明显增加，存活率降低，缺氧后适应组细胞比缺氧复氧组凋亡率低，存活率增加，缺氧后适应＋CT-1组细胞比缺氧后适应组凋亡率进一步降低，存活率进一步增加．Akt磷酸化蛋白水平明显升高，BadmRNA表达下调，加入Akt阻滞剂（A6730）后，这种保护作用被抑制。结论心肌营养素1参与激活Akt信号通路协同缺氧后适应减轻缺氧复氧对心肌细胞的损伤，对心肌细胞起保护作用。

Explore the protective effect of cardiotrophin 1 in ischemic postconditioning of myocardial injury

Objective To study the protective mechanisms of cardiotrophin 1 （CT-1） in myocardial cells and the signaling pathway in isehemic posteonditioning. Methods H9C2 neonatal rat cardiac cell line was used in this study. The cells were divided into six groups： normal control group, hypoxia and reoxygenation group, hypoxia postconditioning group, hypoxia postconditioning ＋CT- 1 group, hypoxia postconditioning ＋CT- 1 ＋Akt blocker group, and hypoxia postconditioning ＋ CT-1 ＋DMSO group. Cell viability was determined by the MTS cell viability assay. Apoptosis were detected by flow cytometry. Expression of Akt was determined by Western-blot. Bad mRNA was determined by Q-PCR. Results The rate of apoptosis was increased in the hypoxia reoxygenation group, and the survival rate of the cells was low.Compared with the hypoxia reoxygenation group ,the viability of cells in the posteonditioning group was increased. The rate of apoptosis in the hypoxia adaptation ＋the CT-1 group was lower than the hypoxia adapted group. The level of Akt phosphorylation was also increased and the expression of Bad mRNA was downregulated.The effect was blocked by the Akt blockers （A6730）. Conclusion Cardiotrophin-1 is involved in activation of Akt signaling pathway collaborative hypoxia. It may also reduce hypoxia reoxygenation injury in myocardial cells.