circRNA_8679作为ceRNA调控miR-128-3p介导的IGF1-Wnt/catenin信号通路促进种植体周围炎环境下hBMSCs成骨分化的机制

Peri-implantitis environment can lead to the decrease of osteogenic differentiation ability of human bone marrow mesenchymal stem cells (hBMSCs). Circular RNAs is an agent in the process of osteogenic differentiation of stem cells. The results of previous experiments show that circRNA_8679 (8679) is down-regulated in hBMSCs in peri-implantitis, interfering with its expression could inhibit osteogenic differentiation, and 8679 could regulate the miR-128-mediated IGF1-Wnt/β-catenin signaling pathway to promote osteogenesis. Therefore, it is speculated that 8679 is related to the inhibition of osteogenic differentiation of hBMSCs in peri-implantitis environment. A hypothesis is proposed that 8679 acts as ceRNA to regulate miR-128 mediated IGF1-Wnt/β-catenin signaling pathway to regulate osteogenic differentiation of hBMSCs in peri-implantitis. The aim of this project is to explore the mechanism of IGF1-Wnt/beta-catenin signaling pathway regulated by 8679-mediated miR-128 in vitro and in vivo to promote osteogenic differentiation. An animal model of peri-implantitis in vivo will be established to provide theoretical basis and therapeutic targets for promoting the recovery of alveolar bone mass around implants and improving the success rate of dental implant restoration.

牙种植周围炎症环境下导致骨髓间充质干细胞（hBMSCs）成骨分化能力减弱，具体机制不明。环状RNA在干细胞成骨分化过程中发挥重要作用。前期实验发现，circRNA_8679（8679）在种植体周围炎环境下的hBMSCs中表达下调，干扰其表达可抑制成骨分化，并且8679可能调控miR-128靶向IGF1-Wnt/β-catenin信号通路促进成骨。因此，我们推测8679与种植体周围炎环境下hBMSCs成骨分化抑制有关，提出“8679作为ceRNA调控miR-128介导IGF1-Wnt/β-catenin信号通路调控成骨分化”假说。本项目拟通过构建体内种植体周围炎动物模型，通过体外和体内实验探讨种植体周围炎环境下8679靶向miR-128调控IGF1-Wnt/β-catenin 信号通路促进成骨分化的机制，为促进种植体周围牙槽骨骨量的恢复,提高牙种植体修复的成功率提供理论基础及治疗靶点。

种植体周围炎是导致种植失败的关键因素之一，目前对于种植体周围炎的治疗仅局限于机械手段或手术清创消除种植体周围结缔组织的炎症，使牙槽骨吸收停止在目前的状态，而对于牙槽骨的再生尚无特别有效的治疗方法。因此，对种植体周围炎引起的骨缺损的治疗具有非常重要的临床价值。Thomas Albrektsson教授认为种植体周围炎发生时，“骨结合”表面的成骨细胞与破骨细胞的平衡状态受到破坏，成骨细胞的活动减弱，出现骨吸收而引起种植体失败。骨髓间充质干细胞（hBMSCs)是成骨细胞的主要来源。炎症状态下hBMSCs成骨分化能力降低导致种植体周围骨形成减少。研究显示环状RNA（circRNAs）对间充质干细胞（MSCs）的成骨分化起着重要的调控作用，所以我们推测在种植体周围炎发病过程中circRNAs可能对hBMSCs的成骨分化发挥重要调控作用。.我们前期通过对成骨诱导后的p-hBMSCs和hBMSCs的circRNAs表达谱进行分析，筛选出了促进p-hBMSCs成骨分化相关的circRNA_8679，并在体外细胞实验验证了circRNA_8679对p-hBMSCs成骨分化的促进作用。我们利用生物信息学软件对其可能的靶miRNAs及靶基因进行预测，发现miR-128-3p是circRNA_8679潜在靶miRNA，且miR-128-3p可能靶向调控IGF1调节成骨分化。.因此本项目从p-hBMSCs中低表达的circRNA_8679入手，构建犬种植体周围炎模型，通过构建cirRNA_8679过表达和干扰质粒，明确cirRNA_8679、miR-128-3p对hBMSCs在体内成骨分化的生物学功能，通过实时荧光定量PCR检测cirRNA_8679和miR-128-3p表达，Western blot检测IGF1-β-catenin信号通路相关蛋白表达。研究发现种植体周围炎环境下cirRNA_8679通过作为ceRNA调控miR-128-3p靶向IGF1-Wnt/β-catenin信号通路促进hBMSCs的成骨分化。.该研究为阐明种植体周围炎环境下hBMSCs成骨能力减弱的机制提供科学依据，同时揭示种植体周围炎环境下hBMSCs成骨分化能力下降的机制，为临床上治疗种植体周围炎环境下种植体周围骨吸收提供理论依据以及潜在治疗靶点。