基于钠离子/牛磺胆酸共转运多肽介导丁香苦苷肝细胞内抗乙肝病毒主动靶向递药系统构建及评价

There are problems about poor specificity and failure to be transmitted within the liver cells in current treatment of hepatitis B in the pharmaceutical preparations, and this has not been able to be broken through. The research group, based on the Na + / Taurocholate transporting polypeptide-mediated, constructed and evaluated the anti-hepatitis B virus liver cells Syringopcroside active targeting drug delivery system. We simulated the trajectory of hepatitis B virus transporting into the liver cells through Na+ / Taurocholic acid. We referred to the mechanism of Taurine deoxycholic acid mediates entering hepatocytes, and chose anti-hepatitis B virus entering vivo and vitro effect of patent medicines drug Syringopcroside as a model drug, by using Taurine ursodeoxycholic acid ligand and Na+/ Taurine transporter peptide receptor binding, the Syringopcroside active liver targeting agent was delivered into the liver cells. The active targeting drug delivery system was evaluated in terms of gene level, cell level, tissue level and the whole animal level by fluorescence quantitative PCR, small living animal imaging and entering vivo fluorescence endoscopic confocal imaging, to clarify the mechanism that the Syringopcroside active liver targeting drug delivery system for transmembrane transport , to achieve transformation of Syringopcroside from liver tissue to liver cells anti hepatitis B virus , and the aim of this study is to solve the bottleneck problem of failure to achieve the intrahepatic drug delivery and the unstablity inside vivo and vitro of Syringopcroside common nano-preparation so as to provide a new idea for anti hepatitis B virus drugs.

目前治疗乙型肝炎的药物制剂，存在专属性差、不能肝细胞内递药问题，一直未能突破。本课题组基于钠离子/牛磺胆酸转运多肽介导，构建丁香苦苷肝细胞内抗乙肝病毒主动靶向递药系统。模拟乙肝病毒通过钠离子/牛磺胆酸转运多肽进入肝细胞内的轨迹，借鉴钠离子/牛磺胆酸转运多肽介导牛磺熊去氧胆酸入肝细胞内的机理，选用体内外抗乙肝病毒作用显著的专利药物丁香苦苷为模型药物，利用牛磺熊去氧胆酸配体与钠离子/牛磺胆酸转运多肽受体结合，将丁香苦苷主动肝靶向制剂递送到肝细胞内。采用荧光定量PCR检测、小动物活体成像及活体荧光内窥式共聚焦成像等技术，从基因水平、细胞水平、组织水平及动物整体水平多方面评价该主动靶向递药系统，阐明丁香苦苷主动肝靶向递药系统透膜转运机制，实现丁香苦苷从肝组织到肝细胞内抗乙型肝炎病毒的转变，旨在解决丁香苦苷普通纳米制剂不能实现肝细胞内给药、体内不稳定的瓶颈问题，为抗乙型肝炎病毒药物提供新的思路。

乙型肝炎病毒（HBV）疾病是一种传染性极高且无法治愈的疾病。我国是HBV高发国家，目前约2亿患者，占全世界1/3，每年约有50万人死于HBV导致的肝硬化、肝癌疾病。目前HBV无法治愈究其原因是HBV属于嗜肝性病毒，仅在肝实质细胞内进行自我复制和传代，药物很难进入病灶肝细胞内，且进去的药物也很快被代谢分解而失效。模型药丁香苦苷抗HBV效果显著，但其化学式结构不稳定，在体内代谢较快。为解决上述两个关键技术问题，本课题借助NTCP转运通道，将抗HBV专利药丁香苦苷制备成纳米靶向制剂（SYR-NPs），实现肝细胞病灶内持久抗HBV的目的。本课题完成了SYR-NPs的制备与评价、SYR-NPs对CBRH-7919细胞毒性及摄取研究、SYR-NPs小动物活体成像研究、SYR-NPs体内药动学和体内分布研究。得到的SYR-NPs分散性良好，呈现淡蓝色乳光，包封率为（28.76±0.87）%，载药量为（6.03±0.15）%，平均粒径为（110.0±1.20）nm，Zeta电位为（-27.5±3.04）mV，证实粒径在80-100nm肝细胞内摄取效果最佳。依据大鼠活体成像结果可知，SYR-NPs组具有明显的肝靶向作用，而且提高了丁香苦苷药物的稳定性，延长了药物的作用时间。体内药动学和体内分布研究结果显示，降低了SYR-NPs在体内的消除速度，使药物在体内维持较高的血药浓度，且可更精准地将SYR-NPs递送至肝脏靶向器官，发挥靶向治疗目的。本项目发表论文4篇，其中SCI论文1篇，授权发明专利1项，获得省中医药管理局科技创新1等奖1项。通过本项目的研究，实现了将抗HBV专利药递送到HBV病灶内给药的目的，以及延长了丁香苦苷药物在体内的作用时间，实现丁香苦苷从肝组织到肝细胞内抗HBV的转变，可为抗HBV药物提供借鉴。