EETs上调瞬时感受器电位M7通道抑制动脉钙化进程的机制研究

Cardiovascular and cerebrovascular events are the most common complication and the leading cause death for patients with chronic kidney disease. Both our preliminary studies and other reports demonstrated arterial calcification played an important role in this process. Recently, it was documented that transient receptor potential melastatin 7(TRPM7) was correlated with arterial calcification. We found the products of arachidonic acid metabolized by cytochrome P450 epoxygenases, epoxyeicosatrienoic acids (EETs) could upregulate TRPM7. However it is still unclear that whether EETs attenuate the progress of arterial calcification and the detail mechanism has not been reported. Based on our previous and preliminary results, we raise the hypothesis that EETs upregulate TRPM7, and attenuate the process of arterial calcification. In this proposal, the in vivo model of artery calcification model induced by warfarin, upregulation of EETs with recombinant adenovirus and Ephx2 knock out mice, histology, patch clamp and reverse high performance liquid chromatography are used to investigate the effect of EETs on arterial calcification. The detail mechanism of EETs-TRPM7- calcium balance- arterial calcification, will be discussed by the in vivo model, smooth muscle cells and ion channel level. This project will provide a new therapeutic strategy for arterial calcification.

心脑血管事件是慢性肾脏病患者最常见的并发症和首位致死病因，国内外报道和我们前期研究均证实，动脉钙化在其中起重要作用。新近瞬时感受器电位M7被发现与动脉钙化密切相关，其表达和活性的增加可抑制动脉钙化进程，我们发现花生四烯酸的细胞色素P450表氧化产物EETs能上调瞬时感受器电位M7，然而EETs能否抑制动脉钙化的进程，具体机制如何，目前尚不清楚。结合前期研究和预实验结果，我们提出EETs通过上调瞬时感受器电位M7，抑制动脉钙化的假说，本研究拟采用华法林诱导动脉钙化在体动物模型，以重组腺病毒以及Ephx2基因敲除小鼠等上调EETs，在整体模型、原代血管平滑肌细胞和离子通道水平，结合组织学、膜片钳和反向HPLC等方法研究EETs对动脉钙化的作用，本研究将深入剖析EETs－瞬时感受器电位M7通道- 动脉钙化的作用规律，为动脉钙化的防治提供新的治疗策略。

动脉钙化是引发慢性肾脏病患者心血管事件高发生率和全因死亡率的主要原因之一。本课题组结合国内外研究进展以及前期预实验结果，提出花生四烯酸的细胞色素P450表氧化产物EETs能上调瞬时感受器电位M7（TRPM7）的表达和活性，进而抑制动脉钙化进程的假说。在该研究中，我们发现，白介素18通过激活细胞外调节蛋白激酶1/2信号通路上调TRPM7表达，诱发钙离子内流，促进血管平滑肌细胞向成骨表型转化。该研究揭示了在动脉钙化进程中，炎症反应发挥非常重要作用。而我们在研究中发现EETs具有显著的抗炎作用，能够有效地改善动脉钙化的发生发展进程。本项目以慢性肾脏病血管钙化模型为基础，深入剖析了EETs－TRPM7－动脉钙化的作用规律，为动脉钙化的防治提供新的治疗策略。