LOC283683-NIPA1-BMPRII途径对胆固醇平衡和动脉粥样硬化的影响及机制研究

Long non-coding RNA (lncRNA) plays an important role in regulation of gene expression and is associated with many diseases. To investigate possible changes in lncRNA expression during atherosclerosis formation, we performed microarray analysis of normal arterial intima and advanced atherosclerotic plaque. The microarray analysis revealed that lncRNA LOC283683 levels and BMPRII levels were significantly down-regulated while NIPA1 levels were markedly up-regulated in advanced atherosclerotic plaque when compared with normal arterial intima. Furthermore, NIPA1 expression was inhibited while BMPRII expression was enhanced by overexpression of LOC283683 in macrophages. Moreover, BMPRII expression was inhibited by overexpression of NIPA1 in macrophages. In addition, cholesterol efflux was increased by overexpression of LOC283683 while reduced by overexpression of NIPA1 in macrophages. Thus, we hypothesize that atherosclerosis development can be affected by LOC283683-NIPA1-BMPRII pathway through regulating cholesterol homeostasis. In this project, we aim to explore the effect and mechanism of LOC283683-NIPA1-BMPRII pathway on cholesterol balance and atherosclerosis development by enhancing expression of LOC283683 and/or NIPA1. Therefore, our study may provide new scientific evidence to establish LOC283683-NIPA1-BMPRII pathway as a new target for regulation of cholesterol homeostasis and prevention of atherosclerosis.

LncRNA在基因调控中起重要作用并与众多疾病相关，为了研究lncRNA对AS的影响，我们通过基因芯片筛选人正常动脉内膜与人动脉内膜斑块中差异表达的lncRNA和mRNA，发现斑块组织的lncRNA LOC283683下调，NIPA1上调而BMPRII下调。在巨噬细胞过表达LOC283683能下调NIPA1表达而上调BMPRII表达。在巨噬细胞过表达NIPA1能下调BMPRII表达。在巨噬细胞过表达LOC283683和NIPA1能分别促进和抑制细胞内胆固醇流出。因此我们提出LOC283683可能通过抑制NIPA1表达从而促进BMPRII表达，发挥促进巨噬细胞内胆固醇流出和抗AS作用。本项目拟通过增强LOC283683和/或NIPA1表达，观察LOC283683-NIPA1-BMPRII对胆固醇平衡和AS形成的影响并探讨相关机制，为确定此途径作为调控胆固醇平衡和防治AS新靶点提供科学依据。

LncRNA 在基因调控中起重要作用并与众多疾病相关，为了研究 lncRNA 对 AS的影响，我们通过基因芯片筛选人正常动脉内膜与人动脉内膜斑块中差异表达的 lncRNA 和mRNA，发现斑块组织的 lncRNA LOC283683 下调，NIPA1 上调而 BMPRII 下调。在巨噬细胞过表达 LOC283683 能下调 NIPA1 表达而上调 BMPRII 表达。在巨噬细胞过表达 NIPA1 能下调BMPRII 表达。在巨噬细胞过表达 LOC283683 和 NIPA1 能分别促进和抑制细胞内胆固醇流出。因此我们提出 LOC283683 可能通过抑制 NIPA1 表达从而促进 BMPRII 表达，发挥促进巨噬细胞内胆固醇流出和抗 AS 作用。本项目通过ChIRP-MS及RIP-PCR检测发现LOC283683与转录因子FUBP-1结合，而FUBP-1可结合NIPA1的启动子从而调控后者转录。我们构建 LOC283683 和/或 NIPA1过表达及干扰载体，发现在细胞水平LOC283683可通过促进FUBP1、抑制NIPA1的表达来上调BMPR2，而回复提示LOC283683可通过抑制NIPA1、促进FUBP1及BMPR2的表达来抑制ICAM-1、VCAM-1及单核细胞粘附因子的表达。体内实验提示敲除LDLR-/-小鼠的NIPA1基因可以抑制巨噬细胞聚集，抑制ICAM-1及VCAM-1的表达，从而减少斑块形成。这些结果提示LOC283683-FUBP1-NIPA1-BMPRII通路可调控单核细胞粘附，对胆固醇平衡和 AS 形成发挥重要作用