PKCα 调控 p120ctn 磷酸化参与颅内动脉瘤形成机制研究

The formation of intracranial aneurysm is still unclear. It was confirmed by our previous study that vascular endothelial injury initiated by VE-Cadherin phosphorylation plays an important role in the formation of intracranial aneurysm.The association of p120catenin phosphorylation with VE-Cadherin shows that p120catenin phosphorylation at S879 disassemble VE-Cadherin junction and disrupt vascular integrity. It has been reported that p120ctn regulates the function of vascular endothelium as an innate immune factor. P120ctn phosphorylation will increase transcription of inflammatory factors, as NF-ΚΒ, Rho and MPO, and induce the inflammatory in vascular endothelium. Inflammatory has been showed to play critical role in the formation of intracranial aneurysm, however, the regulation of inflammatory in endothelial cells is not well clear yet. In this study, we are about to explore the relationship between inflammatory and p120ctn phosphorylation in endothelial cells and try to test the hypothesis that NF-ΚΒ,Rho and MPO signal initiated by p120ctn phosphorylation is involved in the formation of experimental intracranial aneurysm .

颅内动脉瘤形成机制仍不清楚。课题组前期研究证实VE-cadherin磷酸化介导的血管内皮损害在动脉瘤形成中发挥重要作用。通过对VE-cadherin调控的相关因子进行系统分析，结合PKCα调控p120ctn磷酸化不仅影响VE-cadherin磷酸化和血管内皮稳定，且作为体内固有免疫重要调控因子参与血管内皮活化调控的科研实践，提出PKCα调控p120ctn磷酸化在调节血管内皮通透性和血管壁炎症反应两方面共同参与颅内动脉瘤形成的假说。本项目拟应用基因突变、基因干扰、抑制剂和萤火虫酶检测等技术，通过体内和体外实验，分别从动物和细胞水平探讨PKCα调控p120ctn磷酸化介导的NF-ΚΒ，Rho和MPO等信号通路在动脉瘤形成中的作用及调控机制，为探明颅内动脉瘤形成机制奠定实验基础和理论依据。

本课题探讨PKCα特异性磷酸化P120ctn（S879）位点参与颅内动脉瘤形成的分子机制。通过实验性大鼠颅内动脉瘤模型、家兔颅内动脉瘤模型和体外冲击流场系统（T型流室系统）对颅内动脉瘤形成的血流动力学机制实现体内、体外的模拟，我们发现：1、实验性颅内动脉瘤形成过程中血流动力学引起的血管内皮细胞间连接受损是血管内皮损伤的始动环节。2、PKCα 调控流体剪切力作用下血管内皮细胞P120ctn/P-P120ctnS879/ NF-kB 的表达。3、P120ctn的下调通过诱导粘附连接的破坏而加重了冲击流下内皮细胞的损伤。4、P120ctnS879 磷酸化调控流体剪切力作用下血管内皮细胞 NF-kB 表达。5、冲击流作用下激活血管内皮细胞内MAPK信号通路并通过JNK/c-jun、P38/c-fos通路参与内皮细胞损伤。6、冲击流作用下可诱导血管内皮细胞内的circRNA表达变化，可能是血管内皮损伤的潜在分子机制。7、分析动脉瘤病人动脉瘤破裂与气象的关系，发现了动脉瘤破裂相关危险气象因素。上述结论证实了我们提出的“PKCα调控p120ctn磷酸化参与颅内动脉瘤形成机制研究”，为探明颅内动脉瘤形成机制奠定实验基础和理论依据。