糖尿病性骨质疏松症颌骨骨髓间充质干细胞骨再生及骨结合能力的调控机制研究

Diabetes-induced Osteoporosis (DOP) have been gradually recognized and attention in our country，which may lead to the occurrence of oral disease and affect the treatment. To improve the success ratio of dental implant for patients with tooth loss accompanied with diabetes is a difficulty but research hot topic in the dental implant field, and the key is to enhance the implant osteointegration. Stem cell is the key point of tissue regeneration. Recent studies suggested that the biological functions of stem cell are changes under DOP condition，in addition the key cytokines which affecting its biological function were not clear and the mechanism is still unknown. Our previous studies showed that：the proliferation and osteogenesis differentiation were reduce in BMSCs from DOP condition and the expression of miR-182 was increased in BMSCs; the Wnt signaling pathway play an important role in MSCs osteogenesis differentiation progress. Our previous studies have been successfully obtained MSCs from the alveolar bone marrow, and confirmed in situ mandibular alveolar bone formation ability of MSCs to be significantly stronger than the bone marrow MSCs. We will compare the biological features of BMSC and PDLSC from normal donors and DOP patients, and find out the important impact cytokines which affect the function of stem cells from DOP patients. Elucidate the molecular mechanism of stem cell functional abnormality caused by DOP defects and find the possible way that agents modifying the pathway could be of value to bone regeneration in DOP patients. This study may provide a theoretical basis for stem cell tissue engineering on dental implant applying in patients with tooth loss in combination with DOP.

糖尿病性骨质疏松症(DOP)是特指糖尿病导致的骨质疏松，在我国逐渐被认识并重视。DOP是牙列缺损的重要病因，影响种植牙骨结合。干细胞是组织再生的基础，也是骨结合的基础。DOP可导致干细胞功能异常，但其原因与调控机理有待阐明。我们的研究表明DOP状态下骨髓间充质干细胞（BMSCs）成骨分化能力降低，Wnt通路发挥一定调控作用。此外，近期研究表明不同组织来源干细胞功能存在差异，我们发现人颌骨BMSCs成骨能力优于股骨BMSCs，此外，老年颌骨BMSCs骨再生能力明显高于中年股骨BMSCs。本项目拟在前期基础上全面比较正常和DOP条件下颌骨BMSCs的生物学特性变化，阐明调控颌骨BMSCs成骨分化的分子机制，在此基础上建立恢复DOP条件下颌骨BMSCs再生功能的方法。意义在于不仅开发颌骨来源的种子细胞，还揭示DOP对干细胞功能影响和组织再生的调控机制，为提高DOP患者种植牙成功率提供理论依据。

糖尿病引起的全身和局部炎性等改变是导致牙列缺损的重要病因，糖尿病性骨质疏松症（DOP）是特指糖尿病导致的骨质疏松，影响种植牙骨结合。干细胞是组织再生的基础，也是骨结合的基础。DOP可导致干细胞功能异常，但其原因与调控机理有待阐明。本项目在前期研究基础上证实了AMPK通路参与了唑来膦酸盐对高糖条件下成骨细胞、破骨细胞分化生成和功能影响的调控作用。揭示了炎症条件下牙周膜干细胞（PDLSCs）成骨分化能力显著降低，与非经典Wnt/Ca2+通路密切相关的蛋白P38MAPK参与细胞的炎性反应，抑制p38后炎症条件下PDLSCs的成骨分化能力被显著抑制，同时，Wnt关键蛋白GSK3β的磷酸化可影响Wnt通路抑制PDLSCs成骨分化，炎症微环境作用下经典/非经典Wnt通路在PDLSCs成骨分化过程中均发挥重要作用。发现了钽纳米颗粒对MC3T3-E1细胞具有细胞毒性，提高自噬水平有助于减轻钽纳米颗粒对MC3T3-E1细胞的细胞毒性和氧化应激，而通过聚合物辅助沉积技术在TiO2纳米管表面制备出Ta2O5/TiO2纳米管复合涂层促进MC3T3-E1成骨分化。揭示了无定形磷酸钙（NPsACPNPs）/巨噬细胞调控环境削弱了骨髓间充质干细胞（BMSCs）的成骨能力，但胰岛素/聚乳酸⁃羟基乙酸共聚物（PLGA）微球⁃纤维蛋白胶的局部应用可促进糖尿病大鼠胫骨种植体周围的新骨生成，改善种植体骨结合。该项目还证实了下颌骨BMSCs细胞增殖能力弱于股骨BMSCs，成骨能力强于股骨BMSCs。双氯芬酸钠抑制股骨BMSCs的增殖和成骨分化能力，促进下颌骨BMSCs的成骨分化能力，表明下颌骨BMSCs是颌骨再生更具有优势的种子细胞。提取了人牙龈干细胞源外泌体，比较了年轻人和老年人牙髓干细胞生物学活性，为提高糖尿病性骨质疏松症患者种植牙骨再生及骨结合能力提供新的治疗手段和方法。