激活AMPK调节内皮祖细胞治疗长爪沙鼠全脑缺血的作用及机制研究

Stroke is a kind of the global disease which is harmful for human health, and the Mongolian gerbils are ideal animal of global cerebral ischemia model. AMPK activation can improve cerebral ischemia injury, but its mechanism is unclear. Clinical studies have shown that circulating levels of endothelial progenitor cells (EPCs) numbers are positively correlated with good prognosis of cerebral apoplexy, and EPCs can be used as a new target for the treatment of cerebrovascular diseases. Our previous studies have found that activation of AMPK could improve EPCs dysfunction in a global ischemia model of Mongolian gerbil. Accordingly, we speculate that: EPCs number increase and/ or EPCs function enhancement induced by AMPK activation can improve the global cerebral ischemia damage in Mongolian gerbils. To validate this assumption, these projects will perform as following: (1) to determined the relationship of AMPK activation between improved global cerebral ischemia injury and/ or enhanced the number and function of EPCs in Mongolian gerbils; (2) to clarify the mechanism underlying improvement EPCs dysfunction by AMPK activation; (3) to explore the therapeutic action of global ischemia by EPCs transplantation after intervention in vitro. This project will systematically observe the signaling pathways in the treatment of nerve damage of AMPK regulation by using the global cerebral ischemia mode of Mongolian gerbils, this not only improves the medical value of the animal, but also provides theory basis for the application of the model in the field of stroke research.

脑卒中是一种危害人类健康的全球性疾病，长爪沙鼠是最理想的全脑缺血模型动物。AMPK激活可改善脑缺血损伤，但其机制尚不明确。临床研究表明，循环水平内皮祖细胞（EPCs）数量与脑卒中良好预后呈正相关，EPCs可作为治疗脑血管疾病的新靶标。我们前期研究发现激活AMPK可改善长爪沙鼠全脑缺血的EPCs功能障碍。在此基础上，我们推测：激活AMPK提高EPCs数目和/或功能，从而改善长爪的沙鼠全脑缺血损伤。本项目拟对该假设进行以下验证：（1）明确激活AMPK改善长爪沙鼠全脑缺血损伤与其提高EPCs数目和/或功能的关系；（2）阐明激活AMPK改善EPCs功能障碍的可能机制；（3）探索EPCs体外干预后移植对脑缺血的治疗作用。本项目将利用长爪沙鼠全脑缺血模型，系统地观察AMPK调节的信号通路对神经损伤的治疗作用，不仅提高该动物医学上的价值，还可以为该模型在脑卒中研究领域的应用提供理论依据。

脑卒中是一种危害人类健康的全球性疾病，AMPK可改善脑缺血损伤，但机制尚不明确。临床研究表明，循环水平内皮祖细胞（EPCs）数量与脑卒中预后呈正相关，EPCs可作为治疗脑血管疾病的新靶标。脑卒中患者往往合并高脂血症、高血压、糖尿病等基础疾病，导致EPCs移植后效果不佳。因此寻找提高EPCs功能的靶标是EPCs移植治疗的关键。课题组前期研究表明AMPK与提高EPC迁移、黏附和小管形成功能呈正相关，本课题组在前期研究的基础上，探讨机体高脂微环境对EPCs移植治疗的影响，以及AMPK调节EPCs功能的分子机制。. 课题组通过体内实验发现，高脂微环境恶化脑缺血小鼠的皮层血管新生能力；体外实验观察到，在高脂环境下EPC功能障碍与AMPK活性介导的线粒体损伤和氧化应激密切相关；细胞实验显示EPCs中AMPK缺陷诱导肉碱棕榈酰转移酶1A（CPT1A）介导的脂肪酸β氧化（FAO）受损，从而加重氧化应激和线粒体损伤。通过体内EPCs移植治疗显示，AMPK缺陷恶化EPCs介导的血管新生相关功能。这一研究表明AMPK调控FAO是EPCs介导的血管生成的一个重要靶标，靶向AMPK-FAO信号通路有望成为治疗脑卒中伴高脂血症的有效策略。