生物全降解聚左旋乳酸/无定形磷酸钙支架植入大鼠体内后周围组织的钙化

摘要

背景:新型生物全降解聚左旋乳酸/无定形磷酸钙支架展现了良好的应用前景,但支架材料植入后是否引起周围组织钙化尚不明确.目的:观察聚左旋乳酸/无定形磷酸钙支架植入SD大鼠肌内组织后对周围组织钙化的影响.方法:将48只SD大鼠随机均分为实验组与对照组,在实验组大鼠背部肌肉组织中植入聚左旋乳酸/无定形磷酸钙支架,在对照组大鼠背部肌肉组织中植入聚左旋乳酸支架.植入后1,2,4,12周,分别检测肝肾功能及血钙、磷、碱性磷酸酶水平;取支架及周围肌肉组织进行苏木精-伊红染色、钙化Von kossa染色、碱性磷酸酶染色及免疫组织化学核因子κB染色,Western blot检测周围肌肉组织白细胞介素6、骨形成蛋白2水平,并检测组织匀浆钙、碱性磷酸酶含量.结果与结论:两组支架植入未造成大鼠肝肾功能的改变,并且随着植入时间延长亦无明显变化.实验组植入后2,4,12周的白细胞介素6表达少于对照组(P < 0.05),植入后4,12周的核因子κB阳性表达指数、骨形成蛋白2、炎症细胞计数少于对照组(P < 0.05),植入后12周的支架周围组织钙含量低于对照组(P < 0.05);两组周围组织碱性磷酸酶含量表达、VonKossa 钙化相关染色及血中 Ca、P、碱性磷酸酶含量对比均无明显差别(P > 0.05).表明聚左旋乳酸/无定形磷酸钙支架具有良好的安全性及生物相容性,未引起周围组织钙化.%BACKGROUND:Novel fuly biodegradable poly-L-lactic acid/amorphous calcium phosphate (PLLA/ACP) scaffold shows a good prospect of application, but whether the scaffold material has impact on the surrounding tissue calcification is unknown. OBJECTIVE: To observe the influence of PLLA/ACP scaffold material on the calcification of surrounding tissue after implantation of PLLA/ACP scaffold into rats. METHODS:A total of 48 SD rats were divided into experimental group and control group randomly. The experimental group was implanted with PLLA/ACP scaffold material, while the control group was implanted with PLLA scaffold material. At 1, 2, 4, 12 weeks after implantation, the liver function, kidney function and concentrations of calcium, phosphorus, alkaline phosphatase in serum were detected; the muscle tissue around the scaffold was colected for hematoxylin-eosin staining, Von Kossa staining, alkaline phosphatase staining and immunohistochemical staining of nuclear factor-kappa B. Then, western blot assay was used to detect the contents of interleukin-6, bone morphogenetic protein-2, and meanwhile, the contents of calcium and alkaline phosphatase in tissue homogenate were measured. RESULTS AND CONCLUSION:There was no significant difference in either group about the liver and kidney functions at each time. The content of interleukin-6 in the experimental group was less than that in the controlgroup at 2, 4 and 12 weeks after implantation (P < 0.05). The positive expression of nuclear factor-kappa B, bone morphogenetic protein-2 and inflammatory cel count in the experimental group were less than those in the control group at 4 and 12 weeks after implantation (P < 0.05). The content of calcium in the experimental group was less than that in the control group at 12 weeks after implantation (P < 0.05). No difference was found in the expression of alkaline phosphate, the Von Kossa staining and the content of calcium, phosphorus, alkaline phosphatase in the muscle tissue around the scaffold between the two groups (P > 0.05). These findings indicate that the PLLA/ACP scaffold has a good biocompatibility and biological security, which cannot induce peripheral tissue calcification.