黄芪多糖口服吸收促进剂的研究

Study on oral absorption enhancers of Astragalus polysaccharides

该实验利用黄芪多糖中引入的仲氨基与FITC中氰基发生亲核反应,得到FITC荧光标记的黄芪多糖,并采用Caco-2细胞模型评价了低相对分子质量壳聚糖和鱼精蛋白对黄芪多糖的吸收促进作用。结果表明该荧光标记方法稳定性好,灵敏度高;低相对分子质量壳聚糖和鱼精蛋白对细胞毒性作用均较小;2种吸收促进剂对黄芪多糖的吸收均具有一定的促进作用,同时吸收促进剂的比例越大时,作用越明显,低相对分子质量壳聚糖的作用略强于鱼精蛋白。实验前后细胞跨膜电阻(TEER)的变化表明其作用机制可能是吸收促进剂能暂时打开细胞间的紧密连接,增加了膜的流动性,从而提高药物的透过性。

Astragalus polysaccharides was lounded to 4-（2-aminoethylphenol）, followed by labeling the APS-Tyr with fluorescein-5-isothiocyanate （FITC） at the secondary amino group. The absorption enhancement effects of low molecular weight chitosan and protamine on astragalus polysaccharides were evaluated via Caco-2 cell culture model. The results show that the fluoreeent labeling compound has good stability and high sensitivity. On the other hand low molecular weight ehitosan and protamine also can promoted absorption of the astragalus polysaecharides without any eytotoxity, and the absorption increase was more significant with increasing the amount of low molecular weight chitosan and protamine. At the same time,the low molecular weight ehitosan has slightly better effect. The transepithelial electric resistance （TEER） of Caco-2 cells show that absorption enhancers could improve its membrane transport permeability by opening tight junctions between cells and increasing the cell membrane fluidity.