TNF-α通过P38调控Wnt信号通路影响牙周膜间充质干细胞成骨分化分子机制研究

Cell aggregates as seed cells carrier, with rich extracellular matrix and differentiation nich of stem cells in regenerative microenvironment, which can quickly and effectively repair the defect tissue. Periodontal ligament stem cells (PDLSCs) is one of the potential seed cells considerable regeneration of periodontal defects, inflammation is an important factor in the impact of its regeneration. Our previous findings suggested thatTNF-αmediated inflammatory microenvironment cause PDLSCs osteogenic differentiation capacity significantly weakened, and closely related to the regulation of classic and non-canonical Wnt pathway, but how the role of TNF-α in the Wnt pathway mechanism and can be reversed by the Wnt pathway repair function is not clear. Our previous studies also found that the phosphorylation of P38 (p-P38) in the inflammatory microenvironment and Wnt strong correlation with the change, this project intends to indepth study on the basis of preliminary studies the molecular mechanisms regulating the Wnt pathway affect PDLSCs osteogenic differentiation through p-P38 inTNF-α-mediated inflammatory microenvironment, established the scheme of under inflammatory conditions fixed by PDLSCs modification and construction PDLSCs-aggregates regeneration periodontal defects, the reaction clarify polymers and polymer microenvironment of inflammation, and use conditions modified cell aggregates and biological composite materials in inflammatory microenvironment regeneration of alveolar bone defects. The project not only for clinical periodontal inflammation leads to repair damage and provide experimental basis for the treatment of periodontal defects and to establish a new regeneration and therapeutic strategies.

细胞聚合体为干细胞提供再生分化微环境，牙周膜间充质干细胞(PDLSCs)是牙周缺损修复再生种子细胞之一，炎症是影响牙周缺损再生修复的重要因素，我们前期研究表明，TNF-α介导的炎症微环境导致PDLSCs成骨分化能力显著减弱，且与经典与非经典Wnt通路的调控密切相关，但TNF-α如何作用于Wnt通路及能否通过Wnt通路逆转修复功能并不清楚。前期研究同时发现磷酸化P38(p-P38)在炎症微环境与Wnt变化关系密切。本项目拟在前期研究基础上深入研究TNF-α介导的炎症微环境通过p-P38调控Wnt通路影响PDLSCs成骨分化的分子机制，建立炎症条件下修饰PDLSCs并构建PDLSCs聚合体修复再生牙周缺损，阐明聚合体及聚合体微环境对炎症的反应，并利用条件修饰的细胞聚合体与生物材料复合进行炎症微环境下牙槽骨的缺损再生修复，为临床炎症导致的牙周损伤修复提供实验依据并建立新的牙周缺损再生和治疗策略。

牙周炎是一类以牙龈炎症和牙槽骨吸收为主要特征的慢性炎症性疾病，是影响牙周缺损再生修复的重要因素。牙周膜间充质干细胞(PDLSCs)在牙周缺损修复再生过程发挥关键作用。我们前期研究炎症微环境导致PDLSCs成骨分化能力显著减弱，且与经典Wnt通路密切相关。此外，我们发现磷酸化p38(p-p38)在炎症微环境与Wnt变化关系密切。本项目拟在前期研究基础上深入研究TNF-α介导的炎症微环境通过p-p38调控Wnt通路影响PDLSCs成骨分化的分子机制，阐明炎症微环境对PDLSCs聚合体及的影响，并利用条件修饰的细胞聚合体与生物材料复合进行炎症微环境下牙槽骨的缺损再生修复。利用体内、体外实验证实了阻断或抑制p38信号激活可以有效改善炎症来源的PDLSC成骨分化和异位骨形成能力。机制研究方面， 我们阐明炎症微环境通过p38信号介导细胞内Wnt信号和自噬间的级联调控PDLSC分化的分子机制。最后，我们通过修饰p38蛋白PDLSCs聚合体细胞外基质分泌明显增加，利用其修复牙周缺损明显改善了牙周骨再生修复能力。本项目为临床炎症导致的牙周损伤修复提供实验依据并建立新的牙周缺损再生和治疗策略，具有重要的理论和临床参考意义。