靶向性蒿甲醚脂质体的构建及体外靶向性研究

Development of targeted artemether liposomes and targeting effect in vitro

目的构建靶向性蒿甲醚脂质体并评价其对C6脑胶质瘤细胞的体外靶向性。方法以氨基蝶呤(APGA)为靶向性分子,采用化学法合成靶向性功能材料氨基蝶呤-聚乙二醇-二硬脂酰磷脂酰乙醇胺共聚物(APGA-PEG2000-DSPE),以薄膜分散法制备靶向性蒿甲醚脂质体,构建血脑屏障(BBB)-C6脑胶质瘤肿瘤球共培养模型,以香豆素为荧光探针,以共聚焦荧光显微镜观察靶向性脂质体跨越BBB及穿透肿瘤球的能力,以流式细胞仪检测C6细胞对脂质体的摄取情况来评价制剂的靶向性能,采用SRB法考察靶向性脂质体对C6脑胶质瘤细胞的生长抑制作用。结果合成的APGA-PEG2000-DSPE的相对分子质量为3 150,与预测的相对分子质量相吻合;共培养模型显示靶向性脂质体可以更好地跨越BBB并穿透肿瘤球,对于C6脑胶质瘤细胞,靶向性蒿甲醚脂质体、蒿甲醚脂质体、游离蒿甲醚对C6脑胶质瘤细胞的IC50值分别为42、82、95μmol/L。结论构建的靶向性蒿甲醚脂质体可以有效跨越BBB,并靶向运输至脑胶质瘤肿瘤球内部,且具有很强的杀伤脑胶质瘤细胞活性。

Objective To evaluate the targeting and inhibitory effects of the targeted artemether liposomes modified with APGA- PEG2000-DSPE conjugate in vitro. Methods APGA was used as targeted molecular, and the new functional material APGA- PEG2000-DSPE conjugate was synthesized and confirmed by using MALDI-TOF-MS. A kind of targeted artemether liposomes was developed by modifying APGA-PEG2000-DSPE using film dispersed method. Co-culture model of BBB-glioma C6 tumor spheroids was developed, and it was used to study the transporting efficiency across the BBB and the penetration ability of the liposomes into glioma C6 tumor spheroids viewed by a confocal laser scanning microscope. Flow cytometry was used to evaluate the targeting properties of the preparations to C6 glioma cells. SRB method was used to study the inhibitory effect of targeted liposomes on the growth of C6 glioma cells. Results The APGA-PEG2000-DSPE conjugate was confirmed by using MALDI-TOF-MS, and its average mass was 3 150. The co-culture model showed that the targeted liposomes can better transport across the BBB and then penetrate into the glioma C6 tumor spheroids. To C6 glioma cells, the IC50 of the targeted artemether liposomes, artemether liposomes and free artemether were 45, 82, and 95 μmol/L, separately. Conclusion The targeted artemether liposomes could effectively transport across the BBB and penetrate into the glioma C6 tumor spheroids. The targeted artemether liposomes had stronger inhibitory effect on brain glioma cells in vitro.