目的 研究厚朴水提物经Caco-2单层细胞模型双向转运的特征及对细胞膜上P-糖蛋白(P-glycoprotein,P-gp)活性的影响。方法 在经验证的Caco-2细胞单层模型中进行厚朴水提物双向转运实验,根据水提物总抗氧化能力标准曲线计算其转运量,并计算表观渗透系数(P'_app)及溢流率(ER)。以P-gp底物罗丹明123(Rh123)在细胞内的蓄积与外排实验来判断厚朴水提物对Caco-2细胞膜上P-gp活性的影响。结果 厚朴水提物P'_app(AP→BL)值在1×10^-5 cm/s左右,与质量浓度呈正相关,ER值远小于2,对Rh123的蓄积和外排均没有影响。结论 厚朴水提物中与抗氧化作用有关的活性成分群可被较好地吸收,以被动扩散形式转运,不是P-gp底物,也不影响P-gp活性。建立了一种考察厚朴水提物转运特征的新方法,为临床安全合理使用厚朴提供了药动学研究基础。

Objective To evaluate the transport property of water extract from Magnoliae Officinalis Cortex (WEMOC) across Caco-2 monolayer model by bioactivity method and observe the influence on the activity of P-glycoprotein (P-gp) in cell membrane. Methods The validated Caco-2 cell monolayer model was used to observe the bidirection transportation of WEMOC; The amount of WEMOC in the receiver compartment, apparent permeability coefficient (P'_app), and efflux ratio (ER) value could be determined according to the standard curve of total anti-oxidant capacity. The accumulation and efflux of rhodamine123 (Rh123), which is the substrate of P-gp, were determined to evaluate the influence of WEMOC on P-gp. Results P'_app(AP→BL) of WEMOC was around 1 × 10^-5 cm/s, and positively related to concentration; ER was far less than 2; It had no impact on the accumulation and efflux of Rh123. Conclusion The active ingredient groups of WEMOC with anti-oxidant activity can be well absorbed by passive diffusion down a concentration gradient. Neither is it the substrate of P-gp, nor does it have influence on P-gp activity. Our research establishes a novel method to evaluate the transport characteristics of WEMOC, which provides the pharmacokinetic basis for the clinical application of Magnoliae Officinalis Cortex.

国家自然科学基金资助项目(81173567,811173645)