天冬氨酸修饰的纳米硒(PEG2000-ASP@Se)对间充质干细胞增殖与分化能力的影响

Osteoblastic differentiation of mesenchymal stem cell on the aspartic acid functional selenium nanoparticles

采用天冬氨酸(ASP)加以聚乙二醇(PEG2000)修饰制备纳米硒(PEG2000-ASP@Se)并评价其对间充质干细胞(h MSCs)的增殖与分化的影响。实验制备所得PEG2000-ASP@Se纳米粒子通过投射电子显微镜观察其外貌特征,并采用马尔文粒度仪检测其水合粒径。表征结果显示,该纳米粒子具有较好的分散性,其水溶液稳定性较好,水合粒径约为(154±2)nm。根据MTT实验数据,PEG2000-ASP@Se纳米对干细胞增殖能力影响较小。此外,借助流式细胞术,使用Annexin V-FITC/PI双染探针检查纳米是否会导致干细胞凋亡。并检测纳米作用下干细胞内活性氧水平变化情况,从而进一步证实该纳米粒子具有较小的毒副作用。为探究该纳米粒子对干细胞分化潜能的影响作用,使用茜素红染色定性分析干细胞成骨分化过程中产生的矿化结节。上述实验表明,PEG2000-ASP@Se是一个具有良好细胞相容性,毒性较小的促进干细胞成骨分化的纳米药物。

In this study, aspartic acid(ASP) and PEG2000 functional selenium nanoparticles(PEG2000-ASP@Se) were used for stem cell research to identify their effects on mesenchymal stem cells(hMSCs) multiplication and differentiation. The morphology and surface state of PEG2000-ASP@Se were characterized by transmission electron microscope(TEM). The spherical PEG2000-ASP@Se presented monodisperse and homogeneous spherical structure with an average diameter of(154±2) nm. Before determining the role of PEG2000-ASP@Se in hMSCs osteogenic and differentiation, its cytotoxicity was assessed via MTT assay. In addition, the Annexin-V-FITC/propidium iodide double labeling kit was used to investigate if PEG2000-ASP@Se could induce apoptotic cell death with flow cytometry. The generation of ROS had been shown to cause cell apoptosis and drug-induced cytotoxicity. Therefore, the intracellular levels of ROS in PEG2000-ASP@Se treated hMSCs were measured by using dichlorofl uorescein diacetate(DCFH-DA). Alizarin Red staining results suggested that PEG2000-ASP@Se nanoparticles can enhance the osteogenic differentiation of MSC. These results showed that the PEG2000-ASP@Se is a nano-drug with good cell compatibility.