中药引经成分β-细辛醚联合R8、MOG-ab修饰黄芪甲苷纳米粒的双级脑靶向递药系统的研究

Multiple sclerosis is a demyelinating disease of the central nervous system．Astragaloside IV has better effect and lower Blood brain barrier permeability．Cell penetrating peptides and Chinese "Yinjing" can promote the drug through BBB．But the effect and mechanism of the combined construction of the first stage and the two stage targeting is not clear．The research group intends to build two-stage brain targeting drug delivery system that through intranasal administration．This system is composed of R8 and asarone for the first level target molecule， MOG-ab for the second stage．It can pass through the BBB and put the drug directly to lesions；We will evaluate on system’s targeting， targeting mechanism and the synergistic effect of targeted groups performed in vitro and in vivo by using the water quenched fluorescent dye．These studies can improve astragaloside brain lesion delivery effect，due to modern target to pass medicine technology and traditional resuscitation inducing aromatic herbs，nasal to the multiple target to methods combined．These can preliminary clarify the synergistic effect of receptor and its mediated components and the construction mechanism of Two stage brain targeting．These studies can also provid theory and experiment basis on the Chinese Medicine’s two-stage brain targeting drug delivery system，that combined by the “Yinjing” and targeting theories．

多发性硬化症为中枢神经系统脱髓鞘疾病，黄芪甲苷(ASI)治疗该病有效，血脑屏障（BBB）透过率低。前期研究发现中药“引经”与穿膜肽可促进药物BBB的透过，但两者共为一级介导，与抗原介导的二级靶向结合进行双级脑靶向制剂的构建机制研究尚不清楚，课题组拟以脑靶向性好的中药引经成分β-细辛醚、穿膜肽R8为第一级靶向分子、髓鞘少突胶质细胞糖蛋白抗体MOG-ab为第二级靶向分子，构建一种经鼻给药、直接递送药物至髓鞘病变部位的双级脑靶向递药系统；采用水淬灭荧光染色法对递药系统的靶向性、靶向机制及各靶向基团的协同作用进行体内外评价，通过现代靶向递药技术与传统引经药性、鼻腔给药等多种策略联用，提高ASI脑内病变部位的递送效果，初步阐明穿膜肽与引经成分的一级介导协同作用、以及联合二级功能基的双级脑靶向的构建机制，为中药“引经”理论与现代靶向理论结合构建传统中药的双级脑靶向递药系统提供一种新的递药思路。

为解决中医药在治疗多发性硬化症中遇到的因血脑屏障而影响疗效的问题，课题组以中药引经成分β-细辛醚、穿膜肽R8、髓鞘少突胶质细胞糖蛋白抗体MOG-ab为靶向基团，构建了一种经鼻给药、直接递送药物至髓鞘病变部位的双级脑靶向递药系统，对其靶向性进行评价，并以黄芪甲苷和白藜芦醇为模型药物，探讨引经药修饰纳米粒增加药物脑内转运，促进多发性硬化症治疗的效果。成功合成了β-细辛醚的壳聚糖和R8-PPTF串联肽，优化完成R8-PPTF-βCS-NP递药系统的制备；构建16HBE(模拟鼻黏膜)的单层模型和少突胶质细胞MO3.13(模拟髓鞘)的单层模型，采用纳米系统包载香豆素-6，观察修饰后纳米粒的摄取情况，结果表明修饰递药系统的摄取显著高于未修饰和β-细辛醚单独修饰纳米粒，具有更好的经鼻吸收入脑性能和病变部位髓鞘的靶向性，体内靶向性试验表明修饰纳米粒在脑内的荧光强度强于其余各个脏器的荧光强度；MO3.13对修饰纳米粒的摄取量具有浓度、温度和时间的依赖性，摄取转运过程与网格蛋白介导的内吞和胞饮途径有关，有高尔基体和酸性溶酶体的参与，摄取过程需要消耗能量；该递药系统载药性能良好，制备包载黄芪甲苷和白藜芦醇的修饰纳米粒，粒径均小于160nm，带正电荷，电位在13-22 mV之间，载药量分别为3.65%和1.44%；行为学评分及MOG、MAG等药效学实验结果证实，修饰纳米系统能显著提高药物的脑内递送和对多发性硬化症的治疗效果。本研究通过现代靶向递药技术与传统引经药性、鼻腔给药等多种策略联用，提高药物脑内病变部位的递送效果，为中药“引经”理论与现代靶向理论结合构建传统中药的双级脑靶向递药系统提供一种新的递药思路。