主动包载维替泊芬阳离子脂质体用于新生血管和肿瘤靶向光动力治疗  

Active loading of verteporfin into cationic liposome for neovasculature- and tumor-targeted photodynamic therapy

作　　者：万方劼 陈斌龙 杨林洁 殷晴晴 鄢月 杨晔 张强[1] 汪贻广 WAN Fang-jie;CHEN Bin-long;YANG Lin-jie;YIN Qing-qing;YAN Yue;YANG Ye;ZHANG Qiang;WANG Yi-guang(School of Pharmaceutical Sciences,Peking University Health Science Center,Beijing 100191,China)

机构地区：[1]北京大学医学部药学院,北京100191

出　　处：《药学学报》2020年第7期1680-1690,共11页Acta Pharmaceutica Sinica

基　　金：国家自然科学基金资助项目(81703444,81973260)。

摘　　要：本研究设计了一种主动稳定包载维替泊芬(verteporfin,BPD)的新生血管及肿瘤靶向阳离子脂质体(cationic liposome with drug active-loaded in lumen,CLL),并对其体内外理化性质进行探究。采用醋酸钙梯度法对光敏剂BPD进行主动包载,并通过后插法加入阳离子脂质(2,3-二油酰基-丙基)-三甲胺[(2,3-dioleoy-loxy-propyl)-trimethylammonium,DOTAP]成功制备CLL。体外表征结果显示,CLL粒径约100 nm,电位在28 mV左右,体外稳定性较被动载药制剂显著增强。此外,包载于脂质体内腔的BPD通过分子间荧光共振能量转移(homo-FRET)可在递送过程中关闭光敏效应,使光毒性降低。细胞摄取及毒性实验结果证明,正电荷靶向可显著提高血管内皮细胞及肿瘤细胞中药物摄取量,CLL光动力药效显著增强。体内实验结果显示,相比于被动载药制剂,CLL血浆清除速率降低且在肿瘤中特异性蓄积增强。离体组织定量结果显示,CLL在正常组织中分布少,有利于提高其体内安全性。动物实验均按照北京大学医学部实验动物伦理委员会及国际动物实验的指导原则进行。上述实验结果说明,本研究成功构建了新型阳离子靶向脂质体,克服了被动载药制剂在肿瘤治疗中的局限性,使其光动力疗效显著提高。To target neovasculature and tumor cells,a novel cationic liposome with verteporfin(BPD)activeloaded in lumen(CLL)was designed and its basic in vitro and in vivo behaviors were evaluated in this study.Calcium acetate gradient loading method was applied to encapsulate BPD actively and cationic lipid(2,3-dioleoyloxy-propyl)-trimethylammonium(DOTAP)was added by post-insertion for the positive charge of CLL.Results of characterization showed that the diameter and zeta-potential of CLL were around 100 nm and 28 mV,respectively.Compared with passive loading liposomes,CLL significantly enhanced the stability of BPD loading.What’s more,the loaded BPD in lumen could switch off the fluorescence and photosensitization during blood circulation by homo-fluorescence resonance energy transfer(homo-FRET)effect,leading to the diminished phototoxicity to normal tissues.In vitro cellular uptake and cytotoxicity assay exhibited that positive charge dramatically enhanced the uptake of CLL both in vascular endothelial cells and tumor cells leading to superior therapeutic efficacy.In vivo study further showed that CLL reduced the clearance rate and increased tumor accumulation compared with passive loading group.Quantitative results of exvivo organ indicated that negligible CLL distributed in normal organs contributing to low phototoxicity.Animal experiments were conducted according to the Guidelines of the Experimental Animal Ethics Committee of Peking University Health Science Center and International Animal Experiments.In conclusion,we successfully designed a novel cationic targeting liposome that overcame the limitations of passive loading and significantly enhanced the efficacy of photodynamic therapy.

关 键 词：阳离子脂质体 新生血管靶向 肿瘤靶向 光动力治疗 维替泊芬 醋酸钙梯度法 

分 类 号：R943[医药卫生—药剂学]