马钱子与白芍配伍经皮转运吸收行为研究

Compatibility is the characteristics of Traditional Chinese Medicine. The compatibility of Strychni semen and Radix Paeoniae Alba is used to treat rheumatism Arthralgia, and it is also widely used in topical formulations. Currently, compatibility mechanism studies are often administered by oral. And there is no report to clarify mechanism of the transdermal transport route. This project provide a hypothesis that" The compatibility of Strychni semen and Radix Paeoniae Alba delivered by transdermal can reach the purpose of enhancing efficiency and reducing toxicity, and the mechanism of the active ingredients might be relate to the cytochrome P450 enzyme, or change and interaction law of P-gp, or change the cell membrane fluidity. It can affect the dermatological local pharmacokinetic behavior and the distribution in the tissues and organs" based on chinese medicine theory, results of previous experiments and relative references. This project is to clarify the "COLD and WARM, YIN and YANG, to be opposite and complementary to each other " compatibility mechanism of Strychni semen and Radix Paeoniae Alba based on the percutaneous route. Study the mechanism of enhancing efficiency and reducing toxicity from the standpoint of transport and absorption in transdermal route, not only provide scientific guidance for the compatibility of prescriptions but also provide accordance for constructing prescriptions in clinical study. Of course, it also could provide accordance for the evaluation of security in clinical practices of those prescriptions.

配伍是中医用药特色，马钱子与白芍临床常配伍治疗风湿痹证。目前关于配伍"增效减毒"机理研究主要集中在口服给药途径，经皮给药为"中医外治"的主要给药方式，其作用机制如何？本课题结合文献和前期实验结果，提出"马钱子与白芍配伍经皮给药后，通过对易化皮肤转运、P450代谢酶活性表达、P-gp蛋白外排的影响，改变活性成分在皮肤局部药动学行为及在组织器官的分布与代谢，从而达到增效减毒"，进而阐明马钱子与白芍"寒温配伍、一阴一阳、相反相成"配伍内涵。课题从经皮转运的角度研究配伍机理，为中药配伍理论研究提供新思路；通过马钱子与白芍配伍机制的研究，为外用制剂的组方提供理论指导；同时为含马钱子类中药临床用药安全性及有毒中药类方研究开发提供科学依据。

马钱子与白芍临床常配伍外用治疗风湿痹证。课题从易化皮肤转运阻力、P450代谢酶活性表达、P-gp蛋白外排的影响，改变活性成分在皮肤局部药动学行为及在组织器官的分布与代谢，探讨马钱子与白芍配伍增效减毒的内涵。研究结果表明：（1）采用改良Franz扩散池法，配伍经皮给药后马钱子碱和士的宁累积透过量、渗透速率及皮肤滞留率均下降，芍药苷均有增加，其最佳比例为1:6；采用微透析技术配伍抑制了皮下和脑部的马钱子碱和士的宁的吸收，促进了芍药苷的吸收。（2）采用扫描电镜观察经皮给药后马钱子组与配伍组可见角质层表面鳞片脱落和明显的沟壑，皮肤切片变化与氮酮组相似，推测马钱子通过破坏了角质层紧密排列而影响白芍的透皮吸收。（3）采用大鼠微粒体体外孵育法配伍后对CYP2C19、CYP3A4酶的抑制作用增强，白芍总苷对CYP2C19、CYP3A4均存在双向调节。对探针底物大鼠药代动力学中，配伍对CYP3A4的抑制作用增强，推测通过对CYP3A4的抑制起到对白芍的增效作用；配伍组对于CYP1A2的促进作用增强，推测白芍通过促进CYP1A2对马钱子碱的代谢达到减毒的效果。（4）配伍大鼠经皮给药后，马钱子碱与士的宁Cmax减小， Tmax极显著性增大；而两者的 AUC均无显著性变化，提示配伍减缓和延迟了马钱子碱及士的宁的经皮吸收；芍药苷Cmax 显著性增大，Tmax、AUC(0-t) 及AUC(0-∞) 极显著性增大，提示配伍给药极大促进了芍药苷的经皮渗透。马钱子碱和士的宁在心、肝、脾、肺、肾中的含量在2h、6h及24h均有所下降，在皮肤中浓度增加。（5）配伍可以提高P-gp的表达水平，上调MDR1 mRNA的表达，诱导P-gp ATP酶的活性，活化了P-gp的外排功能，进而增加了P-gp对马钱子碱和士的宁的外排，阻碍了毒性成分进入重要组织器官。（6）配伍上调了大鼠前额叶皮质区中的PXR蛋白表达上调，进而上调P-gp的表达水平，提示配伍后通过激活PXR信号通路，调控下游药物转运体P-gp的表达，加速毒性成分的体内清除和外排。