Ca2+/CaN-NFAT信号通路在免疫性冠状动脉损伤和修复中的作用及机制

Coronary artery lesions (CALs) are serious complications in Kawasaki disease (KD), have become the primary cause of acquired heart disease in children, also one of the causes of coronary artery disease in adulthood. Endothelial progenitor cells (EPCs) plays an important role to maintain the integrity of endothelium, regeneration and repair of endothelial. Our previous study found that Ca2+/CaN-NFAT signaling pathway was involved in the development of CALs in children with KD, and its degree of activation may be associated with CALs. The project intends to build immunity CALs model, study the temporal characteristics and regulatory role of Ca2+/CaN-NFAT signaling pathway. We also intends to study the effects of Ca2+/CaN-NFAT signaling pathway down-regulated or over-expression on EPCs and endothelial function by RNA interference technology and pLXSN-NFAT viral vector infection, and the effects of NFAT inhibitor (in vivo and in vitro) on CALs, and to demonstrate the effect and mechanisms of Ca2+/CaN-NFAT signaling pathway on immunity CALs.

川崎病(KD)冠状动脉损伤已成为儿童最常见的获得性心脏疾病，其中内皮细胞损伤极为关键，而内皮祖细胞（EPCs）对内皮损伤后的修复有重要作用。我们前期研究发现Ca2+/CaN-NFAT信号通路参与KD冠状动脉损伤的发生发展，其活化程度可能与冠状动脉病变程度相关。本项目拟通过建立免疫性冠状动脉损伤模型，研究Ca2+/CaN-NFAT信号通路在免疫性冠状动脉损伤时的时空特性，探讨其对免疫性冠脉损伤发生的调控作用及介导介质；通过pLXSN-NFAT病毒载体感染和RNA干扰（RNAi）技术调控EPCs及血管内皮细胞（VECs）Ca2+/CaN-NFAT信号的表达，探讨Ca2+/CaN-NFAT信号过表达或下调对EPCs及VECs功能的影响；并通过NFAT抑制剂体内及体外干预对冠状动脉损伤影响的研究，进而明确Ca2+/CaN-NFAT信号通路对免疫性冠状动脉损伤的作用及相关机制。

川崎病已成为儿童最常见的获得性心脏病之一，但其发病机制尚不明确。本项目研究Ca2+/CaN-NFAT信号通路在川崎病冠状动脉损伤修复过程中的调控作用及机制。.第一部分：体外研究冠状动脉内皮细胞Ca2+/CaN-NFAT信号通路在免疫性冠状动脉损伤中作用的研究发现：KD患者的血清刺激的人冠状动脉内皮细胞（HCAECs）表现出增殖和血管生成显着增强，NFATc1、NFATc3、炎性分子表达升高，且NFATc1和NFATc3的核转运增加。加用环孢霉素A（CsA），发现HCAECs增殖、血管生成减弱，NFATc1和炎症分子表达降低。.第二部分：体内研究Ca2+/CaN-NFAT信号通路在CAWS诱导的免疫性冠状动脉损伤中作用的研究发现：28天CAWS组小鼠主动脉根部炎症浸润明显、胶原纤维缺如，血清、脾脏、心脏及主动脉炎性分子表达增高，且主动脉内膜钙离子增多，心脏细胞核内NFATc1表达增高，间断三天10mg/kg/天CsA给药，血清炎症因子、心脏和主动脉NFATc1、VCAM-1表达均降低。.第三部分：CaN、NFAT1在川崎病患者血清中表达量的研究发现：血清CaN和NFAT1在急性期显着升高，并逐渐降低在发热和亚急性期，以及C反应蛋白，白细胞和中性粒细胞减少计数。而在急性期，发热期和亚急性期，CaN和NFAT1的表达为与健康对照相比，KD患者的表达明显上调。 经过IVIG治疗后,IVIG应答者血清CaN和NFAT1水平显着下降。但是，CaN和NTAT1的水平IVIG无人响应缓慢下降。在发热阶段，KD患者的NFAT1水平较低冠状动脉病变（CALs）（268.82±11.96 ng /ml）比无CALs（285.84±25.13 ng/ml）。然而患有CAL的KD患者的血清CaN水平与没有CAL的KD患者的血清水平无显着差异。