LncRNA Gm12896靶向作用Hey1调控纳米银颗粒/PLGA共涂层条件下种植体骨整合的机制研究

The implant-supported prosthesis which has been widely used in dental prosthetic rehabilitation needs rapid and stable osseointegration. Our previous study indicated the silver nanoparticle/PLGA co-coating could promote the osteogenic differentiation in the process of implant osseointegration, however the mechanism remains unclear. It is reported that long non-coding RNAs（LncRNAs）play important regulatory roles in the process of osteogenesis through transcription and post-transcription levels. The project team carried on in-depth study about LncRNA Gm12896 which presented the largest significant difference in expression by high-throughput chip screening and qPCR verification. Then we utilized bioinformatics methods （GO analysis and KEGG pathway analysis） and speculated that LncRNA Gm12896 inhibits neighboring protein-coding gene Hey1 and subsequently regulates the osteogenic differentiation..Based on the above, the research group plans to make it clear about the function of LncRNA Gm12896 and Hey1 in osteogenic differentiation respectively by its overexpression and silence. RIP and RNA pull-down technology is used to investigate the binding and interaction of LncRNA Gm12896 with HEY1 protein. Then we verify its action mode in the femoral implant model of rats. Through this project, we hope to clarify the regulatory mechanism on LncRNA Gm12896-inhibiting Hey1-promoting osteogenic differentiation. This will provide important theoretical basis and experimental foundation for promoting rapid and stable osseointegration clinically.

口腔种植修复的广泛应用需要快速稳定的骨整合，前期研究发现纳米银颗粒/PLGA共涂层能促进种植体骨整合中的成骨分化，但其机制不明。有研究表明，长链非编码RNAs（LncRNAs）可通过转录及转录后水平调控成骨分化过程。本项目前期通过高通量芯片筛选和qPCR验证发现LncRNA Gm12896差异表达最显著，利用GO及KEGG通路分析等生物信息学方法，推测其可能靶向抑制邻近蛋白编码基因Hey1调控成骨分化过程。.基于此，本项目拟分别过表达和沉默LncRNA Gm12896及Hey1，明确它们在成骨分化中的作用，利用RIP和RNA pull-down技术探讨其与HEY1蛋白的结合及相互作用，并在大鼠股骨种植体模型中进行验证。通过本项目，可分别从细胞、分子和动物水平阐明LncRNA Gm12896-抑制Hey1-促进成骨分化的调控机制，为临床上促进快速稳定的种植体骨整合提供重要理论依据和实验基础。

口腔种植技术已在口腔临床广泛应用，但易发生种植体相关的感染和骨整合不良，导致种植体脱落甚至种植失败等，困扰着广大医师和患者。因此，如何有效地防治感染、增强种植体-骨组织间的骨整合，提高种植成功率，是现今种植体临床应用亟待解决的关键问题。.基于前期研究，纳米银颗粒/聚乳酸-羟基乙酸共聚物（PLGA）共涂层是一种无毒、易于制备且具有强烈抑菌性能的生物医学材料，本项目采用溶剂浇铸法，将其应用在钛种植体表面, 通过体外、间接体内实验和动物（兔）感染模型体内实验，利用多种评价手段，系统评价共涂层钛种植体（NSPTi）的生物学性能、抗感染性能以及骨整合效果，体内外实验均表明该共涂层能够增加种植体表面亲水性，选择性地募集成骨相关蛋白的吸附，促进成骨细胞的增殖和分化，具有促进种植体骨整合的潜力，这为解决种植体临床应用中出现的问题提供了可行的理论基础和实践依据，为种植体表面改性开拓了新的应用领域。.另外，在种植体周微环境方面，项目组进行了多维度的深入研究。为贴近临床实际，项目组利用人牙周膜干细胞（hPDLCs）进行成骨分化过程和炎症调控相关研究。我们的研究表明：上调Lnc RNA MEG3的表达可以抑制BMP2的表达，从而抑制hPDLCs的成骨分化；牙周炎情况下，下调LncRNA MEG3 可通过miR-27a-3p/IGF1轴抑制hPDLCs的成骨分化。因此，Lnc RNA MEG3在牙周膜干细胞成骨分化中发挥重要的调节作用；在炎症调控方面，项目组证实：半乳糖凝集素1（Gal-1）通过调节白介素17A（IL-17A）的表达抑制脂多糖（LPS）诱导的hPDLCs自噬和凋亡。因此，Gal-1在牙周组织再生方面可能具有广阔的应用前景。