The role of Ca(2+) sensitive tyrosine kinase PYK2 as a molecule to transmit cardiovascular stresses

动脉粥样硬化是一种由内皮细胞功能障碍引起的炎症反应，细胞内活性氧在其中起着重要作用。控制动脉粥样硬化的疗法尚未完全开发。氧化还原敏感性酪氨酸激酶PYK 2已显示促进炎症。我们在此首次表明，ROS/p21介导的过早衰老和p21相关的炎症分子的合成在高胆固醇饮食后7天在内皮中诱导，并且在PYK 2缺乏中，这些事件和最终的动脉粥样硬化被显著抑制。研究方法：将PYK 2缺陷小鼠（PYK 2-KO）与ApoE缺陷小鼠（ApoE-KO）杂交，建立PYK 2/ApoE双缺陷小鼠（PYK 2/ApoE-D-KO）。用高胆固醇饲料喂养4周龄小鼠8周。结果：PYK 2/ApoE-D-KO组胸主动脉粥样硬化面积为ApoE-KO组的55%（p<0.01）。骨髓替代实验表明，PYK 2缺陷是一种免疫抑制因子。 ...更多信息 在血管壁和造血细胞中，同样有助于这种减少。在饮食后第7天进行进一步分析。在饮食后7天，PYK 2/ApoE-D-KO的胸主动脉内皮中VCAM 1、MCP-1、LOX-1和ROS的合成比ApoE-KO低48%、31%、78%和74%（均p<0.05）。PYK 2通过上调VAV 2/Racl激活NADPH氧化酶。在第7天，ApoE/PYK 2-D-KO小鼠主动脉内皮中p21蛋白表达和衰老相关的β-gal活性增加，而NADPH抑制剂处理降低了p21蛋白水平，并且在ApoE/PYK 2-D-KO小鼠中消除了p21蛋白水平的这种增加。在培养的WT-EC中用p21-siRNA处理可降低VCAM-1、MCP-1和LOX-1的表达。ROS依赖性转录因子Ets-1的表达在PYK 2-KO-ECs中显著降低，其敲低消除了WT-ECs中的分子诱导。结论：PYK 2通过ROS/p21介导的内皮细胞早衰启动动脉粥样硬化。因此，PYK 2是控制动脉粥样硬化发展的潜在治疗靶点。少

Atherosclerosis is an inflammatory process initiated by endothelial cell (EC) dysfunction in which intracellular reactive oxygen species (ROS) plays crucial role. The therapy to control atherosclerosis has not been fully developed. Redox sensitive tyrosine kinase, PYK2 has been shown to promote inflammation. We here show for the first time that ROS/p21-mediated premature senescence and p21-related synthesis of inflammatory molecules was induced in endothelium just at 7 days after high cholesterol diet and in PYK2 deficiency, these events and eventual atherosclerosis were markedly inhibited. Methods: PYK2 deficient mice (PYK2-KO) were crossbred with ApoE deficient mice (ApoE-KO) and PYK2/ApoE double deficient mice (PYK2/ApoE-D-KO) were established. Four-week-old mice were fed with high-cholesterol-diet for 8 weeks. Results: Atherosclerotic area in the thoracic aorta of PYK2/ApoE-D-KO decreased to 55% of ApoE-KO (p<0.01). Bone marrow replacement experiment revealed that PYK2 deficiency i … More n the vascular wall and in the hematopoietic cells similarly contributes to this reduction. Further analysis was performed at day 7 after diet. Syntheses of VCAM1, MCP-1, LOX-1 and ROS in the endothelium of the thoracic aorta of PYK2/ApoE-D-KO were 48%, 31%, 78% and 74% lower than ApoE-KO (each p<0.05) at 7 days after diet. PYK2 activated NADPH oxidase through upregulation of VAV2/Racl. Expression of p21 protein and senescence associated-□-gal-activity in endothelium of aorta increased in ApoE-KO-mice at day 7, whereas treatment with NADPH-inhibitor decreased p21 protein level and this increase in p21 protein level were abolished in ApoE/PYK2-D-KO mice. Treatment with p21-siRNA in cultured WT-ECs reduced expression of VCAM-1, MCP-1 and LOX-1. Expression of ROS-dependent transcription factor, Ets-1, markedly decreased in PYK2-KO-ECs and its knockdown abolished molecular induction in WT-ECs. Conclusion: PYK2 initiate atherosclerosis through ROS/p21-mediated endothelial premature senescence. Thus, PYK2 is a potential therapeutic target to control development of atherosclerosis. Less