新型可吸收生物玻璃注射体在骨质疏松椎体内支撑及诱导成骨的机制

Mechanism of absorbable bioglass injection for vertebral body supporting and osteogenic induction in osteoporosis

背景:生物玻璃具有良好的生物活性和生物相容性,将其与磷酸钙骨水泥复合形成新型可吸收生物玻璃注射体,可兼具二者优点,预计有更佳的应用空间。目的:探讨新型可吸收生物玻璃注射体在骨质疏松椎体内支撑及诱导成骨的机制。方法:切除27只雌性SD大鼠双侧卵巢,制作骨质疏松模型,造模后1个月将大鼠随机分为3组,均在L_4椎体制作骨缺损,实验组置入新型可吸收生物玻璃注射体,对照1组置入聚甲基丙烯酸甲酯骨水泥,对照2组置入注射性磷酸钙骨水泥。置入后12周,检测植入体抗压强度、降解性能、组织学成骨情况,以及血清骨形态发生蛋白2和转化生长因子β水平。结果与结论:实验组抗压强度、羟基磷灰石沉积量、失重率显著高于两对照组(P<0.05),骨小梁相对体积、厚度和数量显著大于两对照组(P<0.05),骨形态发生蛋白2和转化生长因子β水平显著高于两对照组(P<0.05)。表明新型可吸收生物玻璃注射体可能通过提高骨形态发生蛋白2和转化生长因子β水平,增强骨质疏松椎体的支撑力,提高诱导成骨效果。

BACKGROUND： Bioglass has good biocompatibility and biological activity, which can be combined with calcium phosphate bone cement to form an absorbable bioglass that has the advantages of both materials and is expected to have a better use of space. OBJECTIVE： To explore the mechamism of the new type of absorbable bioglass injection for vertebral body supporting and osteogenic induction in osteoporosis rats. METHODS： Twenty-seven female Sprague-Dawley rats were selected to make osteoporosis models by bilateral ovariectomy, and after 1 month, the rats were randomized into three groups. Bone defect models were established in the lumbar L4 segment of all the rats. Rats in the experimental group were subjected to absorbable bioglass injection; rats in the control group 1 underwent polymethylmethacrylate bone cement injection; and rats in the control group 2 were given injectable calcium phosphate. Twelve weeks after implantation, the compressive strength, degradation and osteogenesis of the implant materials were detected, and levels of serum bone morphogenetic protein-2 and transforming growth factor-β were measured. RESULTS AND CONCLUSION： The compressive strength, hydroxyapatite deposition amount, and weight loss ratio in the experimental group were significantly higher than those in the two control groups（P〈0.05）; the relative volume, thickness and number of bone trabeculae in the experimental group were significantly higher than those in the control groups（P〈0.05）; the bone morphogenetic protein-2 and transforming growth factor-β protein levels in the experimental group were significantly higher than those in the two control groups（P〈0.05）. These findings indicate that the new-type absorbable bioglass can greatly strengthen the vertebral body supporting and promote osteogenic effect in osteoporosis by enhancing the bone morphogenetic protein-2 and transforming growth factor-β protein levels.