不同载银量载银羟基磷灰石细胞相容性与成骨活性的对比研究

Comparative study on cytocompatibility and osteogenic activity for silver-doped hydroxyapatite with different silver contents

目的·制备不同载银量的载银羟基磷灰石(Ag-HAp),探讨不同载银量Ag-HAp的细胞相容性及其对体外培养大鼠骨髓间充质干细胞(BMSC)成骨活性的影响,确定适宜载银量。方法·制备不同载银量(x_(Ag)值)的Ag-HAp(x_(Ag)0.3、x_(Ag)0.5、x_(Ag)0.7)并对其进行表征。将材料分为对照组(x_(Ag)0)和实验组(x_(Ag)0.3、x_(Ag)0.5、x_(Ag)0.7),检测各组材料对BMSC的细胞相容性、成骨相关基因的表达和碱性磷酸酶分泌情况的影响。结果·材料表征结果证实合成产物为Ag-HAp,最终载银量x_(Ag)0.7>x_(Ag)0.5>x_(Ag)0.3。细胞相容性实验结果显示:x_(Ag)0.3-HAp和x_(Ag)0.5-HAp为合格,x_(Ag)0.7-HAp有轻微毒性。Real-time PCR结果显示:与对照组比较,x_(Ag)0.3组和x_(Ag)0.5组成骨相关基因表达上调,x_(Ag)0.7组成骨相关基因表达下调或无明显改变。碱性磷酸酶定性定量实验显示:x_(Ag)0.3组和x_(Ag)0.5组碱性磷酸酶活性均高于对照组,x_(Ag)0.7组碱性磷酸酶活性低于对照组。结论·改变原材料中银的加入量(即改变x_(Ag)值)可制得不同载银量Ag-HAp,当x_(Ag)为0.3、0.5时,其细胞毒性实验结果为合格,且可促进大鼠BMSC成骨相关基因的表达及碱性磷酸酶的分泌。

Objective · To synthesize silver-doped hydroxyapatite (Ag-HAp) with different silver contents, explore their cytocompatibility and effects onthe osteogenetic activity of rat bone marrow mesenchymal stem cells (BMSCs) in vitro, and determine the proper Ag content. Methods · Silver-dopedhydroxyapatite with different silver contents (xAg0, xAg0.3, xAg0.5, and xAg0.7) was synthesized, characterized, and divided into the control group (xAg0 group)and experimental groups (xAg0.3, xAg0.5, and xAg0.7). The effects of Ag-HAp with different silver contents on cytocompatibility, expressions of genes relatedto osteogenesis, and secretion of alkaline phosphatase (ALP) in BMSCs were detected. Results · Characterization results confirmed that the synthesizedproduct was silver-doped hydroxyapatite with silver contents of xAg0.7>xAg0.5>xAg0.3. The cytocompatibility test results showed that the xAg0.3 and xAg0.5groups were qualified to be medical material and the xAg0.7 group had slight toxicity. Real-time PCR results indicated that compared with the controlgroup, the xAg0.3 and xAg0.5 groups had elevated expressions of osteogenesis-related genes and the xAg0.7 group had comparable or decreased expressionsof osteogenesis-related genes. ALP qualitative and quantitative tests showed that the xAg0.3 and xAg0.5 groups had higher ALP activity and the xAg0.7 grouphad lower ALP activity than the control group. Conclusion · Silver-doped hydroxyapatite with different silver contents can be synthesized by changingthe quantity of added silver. When xAg is 0.3 or 0.5, the silver-doped hydroxyapatite is qualified to be medical material and can promote the expressions ofosteogenesis-related genes and the secretion of ALP.