老年黄韧带骨化症中过表达的lncRNA-SNHG4成骨分子网络及应用探究

The consequence of ossification of ligamentum flavum (OLF) is non-tumor bone formation in elderly. To investigate the relevant mechanism is beneficial to the prevention and treatment of OLF and osteoporosis (OP). We have identified lncRNA-SNHG4 that is over-expressed and has homology in human and mouse in OLF tissue by microarray assay. We have also identified the sequence of this molecule and found it is localized in the cytoplasm and nucleus. In addition, lncRNA-SNHG4 was found to be over-expressed in OLF tissues and the process of osteogenic differentiation of both the human mesenchymal stem cells (hMSCs) and the preosteoblasts, however, it is reduced in the femurs of ovariectomized (OVX) and hindlimb-unloaded mice models. Silencing SNHG4 in hMSCs inhibits osteogenic differentiation. We will further investigate the role of SNHG4 in osteogenic differentiation, OLF and OP on the cellular level and with the use of animal models, and identify the pathway through which SNHG4 promotes osteogenesis and the mechanism that SNHG4 dys-expressed. We will also detect the level of SNHG4 in OLF tissue, bone tissue of OP and serum from patients to correlate this molecule with those disorders, providing experimental evidence for SNHG4 as a diagnostic marker and therapeutic target for OLF and OP.

老年黄韧带骨化症（OLF）是非瘤性老年成骨现象，探索其成骨机制有利于防治OLF和骨质疏松症（OP）。我们前期应用基因芯片在OLF组织中筛选出一个显著过表达且具有物种同源性的lncRNA-SNHG4；确定了其全长并定位在细胞浆和细胞核；同时发现SNHG4在OLF组织，间充质干细胞（MSCs）及前成骨细胞的成骨分化过程中过表达；而在卵巢去势及鼠尾悬吊骨质疏松小鼠模型的股骨组织中低表达；沉默hMSCs中SNHG4抑制成骨分化。本次申报：1、在细胞和动物水平阐明SNHG4在成骨分化、OLF和OP发病中的作用；2、揭示SNHG4促进成骨的分子网络及异常表达的机理；3、检测SNHG4在患者OLF组织、OP骨组织及血清中的水平，揭示其与疾病的相关性；为SNHG4作为OLF和OP的诊断标志物及治疗靶点提供理论和实验依据。

老年黄韧带骨化（ossification of ligamentum flavum, OLF) 是造成老年椎椎狭窄的重要原因，研究其机制有助于疾病的防治。本项目完成对OLF组织中的测序，明确成骨通路以及 miRNA-circRNA-lncRNA-mRNA网络对黄韧带骨化的作用。基于成骨通路，研究骨质疏松症影响因素。完善脊柱退变的疾病的氧化应激机制，改善椎间盘的退变。.1、前期已经完成了对黄韧带骨化 组织中的 mRNA, lncRNA,和 circRNA 的芯片分析以及对microRNA 的基因测序工作，通过功能实验确定以 miR19b-3p 为基础的 miRNA-circRNA-lncRNA-mRNA网络对黄韧带骨化的作用以及 miR-342-3p 通过靶点激活 ATF3 促进成骨。.2、通过研究黄韧带骨化，发现影响间充质干细胞与成纤维的细胞成骨作用的因素，可以指导骨质疏松症的治疗。HOX转录反义RNA（HOTAIRM1）通过灭活NF-κB途径促进成骨分化并减轻破骨细胞分化；IGFBP7是PTH促进骨合成代谢的靶基因。.3、研究氧化应激、线粒体功能障碍对于脊柱退行性疾病的影响。靶向Parkin和Nrf2以改善线粒体稳态、氧化还原平衡和终板软骨细胞存活可能是预防椎间盘退变的潜在治疗策略，验证了MitoQ恢复了线粒体动力学平衡，减轻了线粒体-溶酶体融合和溶酶体功能的损害，并增强了Nrf2活性，为MitoQ缓解椎间盘退变提供了证据。