PLGA仿生矿化人工骨对BMSCs体外成骨影响的实验研究  

In vitro study on the influence of biomimetic mineralized PLGA on osteogenesis activity of rat bone marrow- derived mesenchymal stem cell

作　　者：赵铭[1] 郑启新[2] 王军[1] 宁鹏[1] 张月东[1] 

机构地区：[1]山东省泰安市中心医院创伤骨科,山东泰安271000 [2]华中科技大学同济医学院附属协和医院骨科,湖北武汉430022

出　　处：《中国矫形外科杂志》2014年第15期1417-1422,共6页Orthopedic Journal of China

摘　　要：[目的]通过仿生矿化的方法构建聚乳酸-羟基乙酸共聚物(poly lactide-co-glycolide PLGA)人工骨,检测仿生矿化对PLGA生物学性能的影响。[方法]将三维多孔PLGA材料在模拟体液中矿化2周,构建仿生矿化人工骨,应用扫描电镜进行矿化物形貌观察,X射线能谱分析钙磷比值,X射线衍射仪和傅立叶转换红外光谱仪行矿化物物相分析。获取大鼠骨髓基质干细胞(bone mesenchymal stem cells,BMSCs),经传代培养后作为种子细胞与仿生矿化人工骨于体外联合培养,同时以未矿化的PLGA材料和煅烧松质骨为对比,应用RT-PCR的方法测定各组材料上大鼠BMSCs成骨基因表达情况,通过比较成骨基因表达时间先后次序和量的变化,表明各组材料对BMSCs向成骨细胞分化的影响。[结果]矿化后的PLGA材料网孔壁有磷灰石矿化层形成,矿化物主要成分为羟基磷灰石,钙磷比为1.53,类似于人骨无机质。大鼠BMSCs在三种材料上培养7 d后,碱性磷酸酶(alkaline phosphatase,ALP)相对表达水平煅烧松质骨组>矿化组>未矿化组(P<0.05);骨涎蛋白(bonesialoprotein,BSP)和骨钙素(osteocalcin,OCN)在各组均没有表达。培养14 d后ALP相对表达水平煅烧松质骨组和矿化组无显著性差别(P>0.05),均明显高于未矿化组(P<0.05);煅烧松质骨组BSP相对表达水平明显高于矿化组(P<0.05);OCN在煅烧松质骨组有少量表达。培养21 d后ALP相对表达水平未矿化组>矿化组>煅烧松质骨组(P<0.05);BSP和OCN在表达水平显示矿化组和煅烧松质骨组没有明显差别(P>0.05),均明显高于未矿化组(P<0.05)。[结论]PLGA仿生矿化人工骨能够显著提高骨髓基质干细胞成骨基因的表达,促进其向成骨细胞分化。[ Objective] Biomimetic mineralized poly （lactide- co- glycolide） （PLGA） was evaluated for its ability to support bone mesenchymal stem cell （BMSC） osteogenic differentiation, in vitro, in order to assess its potential use in clinical tissue - engineering strategies. [ Methods ] 3 - D - porous - PLGA scaffolds were mineralized in simulated body fluid for 2 weeks. The morphology, composition, and phase of the minerals grown on PLGA were analyzed using SME, FTIR, and XRD, respectively. Rat BMSCs were isolated and cocuhured with mineralized PLGA, unmineralized PLGA and with sintered bone as the control. Osteoblast - related markers, alkaline phosphatase, bone sialoprotein, and osteocalcin mRNA expression were eval- uated in the BMSCs after 7, 14, and 21 days of cocultivation with each group of scaffolds. Expression of these osteoblast - spe- cific genes can be explained by BMSC differentiation along the osteoblastic pathways. [ Results] There was an obvious mineral coating on the surface of the 3 - D porous - PLGA. The main component of this mineral was carbonate apatite, with a Ca/P ratio of 1.53, similar to the major mineral component of bone tissue. After 7 days of cocuhivation, the expression level of ALP mRNA was the highest in the sintered bone group and the lowest in the unmineralized PLGA group （P 〈 0.05） . There was no expres- sion of BSP and OCN mRNA in any of the 3 groups. At 14 days, BMSCs from both the sintered bone and the mineralized PLGA groups expressed signifcantly higher levels of ALP mRNA than those from the unmineralized PLGA group （P 〈 0. 05 ） . The expression level of BSP in the sintered bone group was higher than in the mineralized PLGA group （P 〈 0.05） . There was a low expression level of OCN mRNA in the sintered bone group. At 21 days, the expression level of ALP mRNA was the highest inthe unmineralized PLGA group, and the lowest in the sintered bone group （P 〈 0. 05 ） . No statistically signifcant differences were observed in the expression levels of BS

关 键 词：仿生 聚乳酸-羟基乙酸 骨髓基质干细胞 成骨分化 

分 类 号：R318.08[医药卫生—生物医学工程]