Screening and identification of the active components from Puerariae Radix by HUVEC/CMC-LC-MS2.

Puerariae Radix (PR) serves as food and medicinal plant for thousands of years with explicit efficacy for heart diseases, while biological target specifically binding-oriented screening of the active components in PR remains a preliminary stage. Cell membrane chromatography (CMC) is newly developed approach where interactions between active components and certain biological targets can be effectively studied, Human umbilical vein endothelial cell (HUVEC) membrane, with its abundant receptors such as ß and AT1, is most eligible for constructing CMC. In this study, an HUVEC/CMC-LC-MS2 system was developed for screening active components in PR, 11 compounds were screened out and four of them were identified. Besides puerarin, the rest identified are daidzin, pueroside D and 3'-hydroxypuerarin. The study provides more reference for CMC applications and PR exploitation.

[Active components of Ligustrum lucidum inhibiting hepatitis C virus replicase activity].

Based on previous report that the Chinese herb Ligustrum lucidum (LL) extract directly inhibited hepatitis C virus (HCV) replicase (NS5B) activity, the active components of LL extract to inhibit HCV NS5B activity and their inhibition mode were investigated in this study. LL extract was separated using ethyl acetate and thin layer chromatography (TLC). The inhibitory activity of separated fractions on HCV NS5B was analyzed by the inhibitory assay of NS5B activity. The results showed that only fractions 1 and 2 inhibited NS5B activity, and fraction 2 possessed higher inhibitory activity than fraction 1. HPLC analysis combined with inhibitory assays indicated that ursolic acid and oleanolic acid are the active components within fractions 1 and 2 to inhibit NS5B activity, separately. Moreover, oleanolic acid possessed higher inhibitory activity than ursolic acid. Further inhibition mode analysis found that both oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors. The Ki values of ursolic acid and oleanolic acid were about 4.7 microg x mL(-1) (10 micromol x kg(-1)) and 2.5 microg x mL(-1) (5.5 micromol x kg(-1)), respectively. Taken together, these results demonstrated that oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors, implying that the two natural products have potential value for HCV therapy.

Cardiac muscle sarcolemma chromatographic stationary phase and its potential application in drug screening.

A new bioactive packing material for liquid chromatography, sarcolemma chromatography stationary phase (SCSP), is presented. Its surface characteristics are investigated, and it is found that the acceptors embedded in sarcolemma remained bioactive for more than a week. The retention behavior of antagonists and activators related to cardiac muscle sarcolemma on the SCSP chromatographic column shows the screening function of the SCSP column, and the retention behavior of the active components in the aether extract from the Chinese herb Ligusticum chuanxiong Hort. on the SCSP column reveals, to a certain extent, the separation function of the SCSP column. These suggest that SCSP is a potentially useful material in drug screening.

[Study on the interactions between Ligusticum chuanxiong extract and cardiac muscle membrane receptors by CMSP chromatography].

OBJECTIVE: To study the interactions between Ligusticum chuanxiong Hort extract and cardiac muscle membrane receptors. METHOD: The cell membrane of rabbit cardiac muscle was fixed on silicon to make cell membrane stationary phase (CMSP), and then the interactions were studied by comparing the retention characteristics of the extracts from different solvents with those of the antagonists or activators corresponding to known receptors in cardiac muscle membrane, and by competition effect on the retention characteristics of extracts when adding the antagonists or activators into the mobile phase. RESULT: Water extract and ethanol extract both had retentions on CMSP; the retention characteristics of water extract could be affected when water extract was in competition with the antagonists for alpha receptor, and could not be affected when with the activator beta1 receptor. CONCLUSION: It is possible that some components in water extract may combine with alpha receptor and no component with beta1 receptor, and that some components in ethanol extract may combine with cardiac muscle cell membrane. The process between active components and receptors in vivo can be imitated through the interactions between drugs and CMSP. The method provides references for the resolution of two applications: to screen the active components from Chinese medicine, and to figure out the type of receptors involved.

[Study on the interactions between four components in Ligusticum chuanxiong rhizome and acceptors on cardiac muscle membrane].

OBJECTIVE: To study the interactions between four components in Ligusticum chuanxiong rhizome and heart cell membrane acceptors. METHOD: Through observing the retention characteristics of the four components (tetramethylpyrazine, vanillic, chrysophol, ferulic acid) on cell membrane stationary phase (CMSP) chromatographic column, whether the components combine with cell membrane acceptors was studied, and through further comparing the retention characteristics with those of known activators or antagonists corresponding to cell membrane acceptors, the kind of acceptor with which one component combines was studied. RESULT: Tetramethylpyrazine, vanillic and chrysophol had retention on CMSP chromatographic column while ferulic acid hadn't. The retention characteristics of tetramethylpyrazine were similar to activator and antagonist corresponding to a acceptor, vanillic with beta1 acceptor activator. CONCLUSION: Tetramethylpyrazine, vanillic and chrysophol can all combine with cardiac muscle membrane acceptors, while ferulic acid can not; tetramethylpyrazine probably acts on a acceptor and vanillic acts on beta1 acceptor.

[Screening models and techniques for medicine and its application in the studies on the active components of Chinese medicine].

The development of modern biologic techniques have provided new techniques and approaches for the modern studies on active components of Chinese medicine. This article is a review of four kinds of screening models and corresponding techniques for medicine and their applications in the studies on the active components of Chinese medicine. The four aspects comprise the whole animal models, receptor models and molecular biochromatography, cell models and cell membrane chromatography, and gene chip techniques. It will provide references for promoting studies and accelerating modernization of Chinese medicine.