Investigation On The ’Liang’ Relationship Of Herb-pair’Yuanzhi-Shichangpu’ Based On The Regulation Of P-glycoprotein

Herb Formula ("Fu-Fang" in Chinese), as the main pattern of prescribed Chinese medicines. But the Fu-Fang is difficult to research. Herb-pair is simple and easy to study. The sentence of’It’s better to utilize the herb-pair with compatibility of Xiangxu and Xiangshi’ was recorded in the book’Shen Nong Materia Medica’. Under the guidance of the theories of ’Liang’relationship which contain ’Xiang xu’ and ’Xiang shi’, Polygala tenuifolia Willd.-Acorus tatarinowii Schott. which was used in treatment of Alzheimer’s disease was selected as the research object. Research on regulation of P-glycoprotein(P-gp), intestinal absorption in vitro by everted gut sac technique, pharmacokinetics of herbs in vivo was helpful to reveal the compatibility regulation of herb-pair. These findings will help the understanding of the biological properties of Polygala tenuifolia Willd.-Acorus tatarinowii Schott. and will guide the clinical use of them. Research on synergistic effect of herb-pair is one of the important issues for intensive understanding of therapeutic benefits of Traditional Chinese Medicine The full text included five parts listed as follows.1. We evaluated the cytotoxicity and multi-drug resistance(MDR)-reversal potency of volatile oil of Acorus tatarinowii Schott., α-and β-asarone in Caco-2cells by MTT assay. The volatile oil, α-and β-asarone could enhance vincristine and Polygala tenuifolia Willd. extracts induced cytotoxicity. These results showed that volatile oil, α-and β-asarone reversed the MDR through the inhibition of P-gp function. The extract of Polygala tenuifolia Willd. had substrates of P-gp.Functional ability was assessed by measuring the accumulation and efflux of rhodamine123. These results showed that volatile oil, α-and β-asarone induce an increase in intracellular accumulation and reduce the efflux of Rhodamine123in a concentration-dependent manner, however, a-asarone was less potent than β-asarone for inhibition of P-gp transport function.The expression level of P-gp and MDR1mRNA in Caco-2cells was determined by flow cytometry and RT-PCR. These results indicated that volatile oil, α-and β-asarone could down-regulate MDR1mRNA and P-gp protein levels in Caco-2cells, however, a-asarone was less potent than β-asarone for inhibition of P-gp transport function.2. The everted gut sac technique was used to screen volatile oil of Acorus tatarinowii Schott., α-and β-asarone for their ability to enhance the absorption of3,4,5-trimethoxycinnamic acid (TMCA) in vitro by high performance liquid chromatography (HPLC). These results indicated that volatile oil, α-and β-asarone could increase the absorption of TMCA in jejunum and ileum, espacilly in ileum. Because the volatile oil, α-and β-asarone could inhibit the function of P-gp, and thus potentially enhance drug absorption.3. Here it is shown that rat treated with AICl3(subcutaneous injection) plus D-galactose (intraperitoneal injection) represent a good model of Alzheimer’s disease. A water maze behavioral test was performed to evaluate AICl3and D-galactose effects on spatial reference learning memory of rats. It also have detected the acetylcholinesterase activity of brain homogenates of rats. These results indicated that this mouse model can be a useful model for studying on the pharmacokinetics and tissue distribution of Polygala tenuifolia Willd. and Acorus tatarinowii Schott. in rats.4. A HPLC method for analysis of the TMCA in plasma is established. A sensitive and specific gas chromatographic-mass spectrometry with selected ion monitoring method has been developed for simultaneous identification and quantification of methyl eugenol, trans-methyl isoeugenol, cis-methyl isoeugenol, α-and β-asarone in rat plasma. The drug-drug interaction between Acorus tatarinowii Schott. and Polygala tenuifolia Willd. in nomal and model rats with orally adminitrated was investigated by the above method. The study showed that Acorus tatarinowii Schott could increase the bioavailability and decelerate the elimination of TMCA in the plasma of nomal and model rats. Meanwhile, Polygala tenuifolia Willd. could increase the bioavailability and decelerated the elimination of methyl eugenol, trans-methyl isoeugenol, cis-methyl isoeugenol, α-and β-asarone in the plasma of nomal and model rat. These results reflected the synergistic interaction of Polygala tenuifolia Willd.-Acorus tatarinowii Schott..5. A HPLC method for analysis of the TMCA in tissue is established. Study on the tissue distribution of TMCA in nomal and model rat after oral administration of Polygala tenuifolia Willd. and Acorus tatarinowii Schott.-Polygala tenuifolia Willd.. These results showed that the concentrations of TMCA in kidney, lung and heart were higher than that in the spleen, brain and liver. It was discovered that the content of TMCA was obviously increased in different tissues after administration of Acorus tatarinowii Schott.-Polygala tenuifolia Willd., especially in brain which should be relative to the inhibition of P-gp by Acorus tatarinowii Schott..