应用OCT研究IncRNA-CRNDE调控巨噬细胞MMP2/MMP9从而影响易损斑块破裂的作用及机制

Atherosclerotic plaque rupture with luminal thrombosis is the most common mechanism responsible for the majority of acute coronary syndromes and sudden coronary death. Long noncoding RNAs(IncRNAs) have been recognized to play diverse and important roles in atherosclerotic plaque progression and plaque rupture. However, the functional role of lncRNAs in atherosclerotic plaque rupture is less well known. Macrophage plays a major role in all phases of atherosclerosis including plaque rupture and subsequent thrombus formation. Our experimental data have indicated that IncRNA-CRNDE can up-regulate the expression of MMP-2/MMP-9 in THP-1 monocyte-derived macrophages. Therefore, we postulate that CRNDE can regulate the pathological process of plaque rupture by up-regulating the expression of MMP-2/MMP-9 in macrophage, this is a novel mechanism for plaque rupture and possibly relates to the NF-kappaB activation and MAPK signalling pathway. Recently, intravascular optical coherence tomography (OCT), a high-resolution coronary imaging modality, with an axial resolution of approximately 10μm, has been introduced into the clinical setting. OCT can provide information about the microstructure of the coronary artery and has been shown to be capable of detailed tissue characterization. In this study, we will employ a wide range of molecular biological techniques including gene transfection, western blotting and quantitative RT-PCR. In addition, multiple advanced imaging modalities including optical coherence tomography, virtual-histology and acoustic contrast will be performed to investigate the effect of IncRNA-CRNDE on plaque progression and to disclose the mechanism of the macrophage activiation by CRNDE. Our results may provide a new therapeutic target of the pharmacological intervention to atherosclerosis.

动脉粥样硬化斑块(AS)破裂是急性冠脉综合征的主要病理机制。IncRNA被认为在AS进展中具有重要作用，巨噬细胞在AS破裂过程中发挥至关重要作用。IncRNAs是否通过调控破裂斑块内巨噬细胞活性，从而影响斑块破裂过程? 至今尚不清楚。我们前期发现IncRNA-CRNDE可上调巨噬细胞MMP-2及MMP-9表达。因此，我们推测CRNDE可能通过调控MMP-2及MMP-9表达从而参与斑块破裂，并可能与 NF-kB、 MAPK等信号转导途径有关。光学相干断层成像是血管内分辨率最高影像技术，能准确判断斑块破裂及巨噬细胞。我们课题将利用光学相干断层成像、虚拟组织学及声学造影等多种先进影像模式并结合基因转染、基因沉默、Western blot、原位杂交及RT-PCR等技术，从细胞到整体水平研究CRNDE对巨噬细胞及AS斑块破裂的作用及其机制。本课题将从新视觉阐明斑块破裂机制,并为AS治疗提供新靶点。

冠心病是心血管疾病中最主要的疾病，急性冠状动脉综合征（acute coronary syndrome,ACS）是冠心病的一种严重类型，其致死率高，而易损斑块（thin-capped fibroatheromas,TCFA）破裂是ACS的首要原因，其结构特点为纤维帽薄、脂质核心大，并含有大量巨噬细胞等炎症细胞及少量的平滑肌细胞。晚期动脉粥样硬化斑块中发展迅速、容易进展成为急性心肌梗死的罪犯病变，目前的残存风险依然较高，巨噬细胞在AS进展与破裂过程中发挥至关重要作用。IncRNAs是否通过调控破裂斑块内巨噬细胞活性，从而影响斑块破裂过程? 至今尚不清楚。光学相干断层成像是血管内分辨率最高影像技术，能准确判断斑块破裂及巨噬细胞。我们课题将利用光学相干断层成像、血管内超声等多种先进影像模式并结合基因转染、基因沉默、Western blot、原位杂交及RT-PCR等技术，从细胞到整体水平研究非编码RNA（ncRNAs）对巨噬细胞及AS斑块破裂的作用及其机制。理想的TCFA动物模型能形成与人类晚期斑块类似的病变，并能产生与人类相似的心血管事件。我们构建了Fbn1C1039G基因杂合突变的LDLR-/-小鼠经高脂喂养后能形成类似于人类晚期动脉粥样硬化的不稳定斑块，具有坏死核增大、纤维帽变薄、胶原含量减少、炎症细胞增多、外向重构等特点，且能自发发生斑块破裂，继发血栓形成。更重要的是，我们构建circRNAs/lncRNAs/miRNAs在动脉粥样硬化进展中的非编码RNA调控网络，并验证部分关键调控ncRNAs，阐明IncRNA-CRNDE、RAPIA在巨噬细胞中的调控作用以及其在斑块进展中与干预中的作用及调控机制。同时揭示TMAO水平增高与斑块易损性增加有相关性。另外，我们建立非编码circRNAs在平滑肌分化增殖中的调控网络。本课题目前的研究成果与未来的进一步深入为TCFA与ACS的诊断、治疗及预后提供新靶点与新的参考。