Connexin43在颈椎后纵韧带骨化发生过程中的功能和分子机制研究

Cervical ossification of the posterior longitudinal ligament (OPLL) is one of the most common spinal diseases and the pathogenic mechanism has not been fully understood. Connexin 43, responsible for intercellular signal transduction, is one important regulatory protein for bone formation in human, but its effect on OPLL development has not been clear. Our previous studies have found that the expression of Cx43 from OPLL ligament fibroblasts was significantly higher than that from non-OPLL cells. We also found that mechanical strain induced Cx43 expression in spinal ligament fibroblasts from the patients with OPLL, and the induction effect could be suppressed by Cx43 knockdown. In this study, we will employ the cells from cervical posterior longitudinal ligament and the mechanical strain induced osteoblastic differentiation model, to investigate the function and molecular mechanism of Cx43 and related signaling pathways in the development of OPLL by multiple molecular biological methods. Expressions of Cx43 and related downstream factors in tissue specimen will also be determined in clinical studies. This programme will increase the understanding of OPLL development in the view of intercellular signal transduction, establish foundation and provide a new rationale for the future development of molecular-targeting drug to treat patients with OPLL.

颈椎后纵韧带骨化症（OPLL）是常见的脊柱疾患，但其发病机制尚不完全清楚。承担细胞间信号传递的缝隙连接蛋白Cx43是人体内骨形成的重要调节蛋白，但其在OPLL中作用尚未明确。课题组前期研究发现Cx43在OPLL患者的颈椎后纵韧带组织细胞内的表达量明显高于非OPLL患者，机械应力能诱导细胞内Cx43的蛋白表达增高，干扰Cx43的表达能抑制机械应力对细胞骨向分化的诱导作用，然而Cx43在OPLL中发挥作用的分子机制国内外尚无相关报道。本课题拟以体外培养的颈椎后纵韧带组织细胞为研究对象，以机械应力诱导细胞骨向分化为模型，通过多种分子生物学方法，研究Cx43在OPLL发生发展过程中的功能及分子机制，阐明与其相关的信号传导通路，并通过临床组织样本进行验证。本课题的研究将有助于从细胞间信号传递的角度增强对OPLL发生发展机制的认识，为OPLL的靶点药物研究奠定基础和提供新思路。

颈椎后纵韧带骨化症（OPLL）是常见的脊柱疾患，但其发病机制尚不完全清楚。本项目研究以体外培养的颈椎后纵韧带组织细胞为研究对象，以机械应力诱导细胞骨向分化为模型，通过体内、体外实验，以及多种分子生物学方法对Cx43在OPLL发生发展过程中的功能及分子机制进行了研究。研究结果发现缝隙连接蛋白Cx43通过下游MAPK（ERK和p38）信号通路调控颈椎后纵韧带组织细胞骨向分化，但这种调控作用与机械应力刺激的强度和时间相关。因此项目进一步对内质网应激ERS在OPLL中的作用进行了研究。结果发现OPLL患者后纵韧带组织细胞存在内质网应激（ERS）反应，ERS的感受器蛋白（PERK）和转导蛋白（OASIS）表达明显增高，干扰PERK蛋白表达能抑制细胞骨向分化进程。因此，我们推测ERS在OPLL发生过程中的发挥作用，并可能对Cx43和下游信号通路的进行调控影响细胞成骨分化。该项目研究有助于从细胞间信号传递的角度增强对OPLL发生发展机制的认识，为OPLL的靶点药物研究奠定基础和提供新思路。