Identification of active ingredients mediating anti-platelet aggregation effects of BuyangHuanwu decoction using a platelet binding assay, solid phase extraction, and HPLC-MS/MS.

BuyangHuanwu decoction (BHD) is widely used as a traditional herbal medicine because of its antithrombotic effect, which is attributed to the inhibition of platelet aggregation; however, its active compounds remain unknown. In this study, we developed a method involving platelet binding, solid-phase extraction, and HPLC-MS/MS for screening BHD compounds with potential anti-platelet aggregation properties. Five compounds showing platelet binding affinity were identified as 6-hydroxykaempferol-di-O-glucoside, paeoniflorin, calycosin-7-O-ß-d-glucoside, galloylpaeoniflorin, and formononetin-7-O-ß-d-glucoside. The results of anti-platelet aggregation experiments in vitro confirmed that these compounds inhibited adenosine diphosphate-induced platelet aggregation. Our results suggest that a platelet binding assay combined with solid-phase extraction and HPLC-MS/MS is an effective method for screening anti-platelet aggregation agents in traditional Chinese medicines.

Biospecific isolation and characterization of angiogenesis-promoting ingredients in Buyang Huanwu decoction using affinity chromatography on rat brain microvascular endothelial cells combined with solid-phase extraction, and HPLC-MS/MS.

Buyang Huanwu decoction (BHD) was reported to exert angiogenesis-promoting effects, but its active ingredients remain unknown. In this study, we developed a method to screen potential angiogenesis-promoting compounds in BHD, which involved biospecific isolation using live rat brain microvascular endothelial cells (rBMECs) and characterization using solid-phase extraction (SPE) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Six compounds showed binding affinity to rBMECs and were further identified as 6-hydroxykaempferol-di-O-glucoside, paeoniflorin, calycosin-7-O-ß-D-glucoside, galloylpaeoniflorin, formononetin-7-O-ß-D-glucoside, and (3R)-7,2'-hydroxy-3',4'-dimethoxy-isoflavan. The results indicated that five of them except 6-hydroxykaempferol-di-O-glucoside showed a protective effect against oxygen glucose deprivation/reperfusion injury in rBMECs and upregulated the secretion of vascular endothelial growth factor and basic fibroblast growth factor, suggesting a mechanism underlying their angiogenic activity. Our findings suggest that biospecific live cell-based isolation combined with SPE and HPLC-MS/MS is an effective method for screening potential bioactive components in traditional Chinese medicines.

Effect of ferulic acid on the brain pharmacokinetics of tetramethylpyrazine in conscious rats.

1. In traditional Chinese medicine, Angelica sinensis is often coprescribed with Ligusticum chuanxiong Hort for the treatment of ischemic cerebrovascular diseases. Tetramethylpyrazine (TMP) is one of the most important active ingredients isolated from Ligusticum chuanxiong Hort; ferulic acid (FA) is the main water-soluble component of Angelica sinensis. 2. The purpose of this study is to investigate the possible effect of FA on the brain pharmacokinetics of TMP in conscious Sprague-Dawley rats. The pharmacokinetic parameters of TMP were investigated in brain microdialysates after oral and intravenous administration of TMP (4 mg/kg) to rats in the absence and presence of FA (5 mg/kg). Samples were collected at timed intervals for the measurement of TMP by a rapid and sensitive UPLC-MS/MS method. 3. The pharmacokinetic parameters were calculated by noncompartmental analysis for brain microdialysates. The brain pharmacokinetic data for TMP showed significant increases in Cmax, t1/2, AUC0-inf and MRT0-inf after combination with FA. After intragastric administration with FA, there were significant decreases in the Tmax (from 38.33 ± 5.77 to 21 ± 5.48 min; p < 0.01) of TMP. This study indicated that potential drug-drug interaction between TMP and FA should be taken into consideration and the combined administration is beneficial in improving the bioavailability of TMP in the brain.

Effect of stimulating the acupoints Feishu (BL 13) and Dazhui (GV 14) on transdermal uptake of sinapine thiocyanate in asthma gel.

OBJECTIVE: To investigate the effect of stimulating the acupoints Feishu (BL 13) and Dazhui (GV 14) on the transdermal uptake of sinapine thiocyanate contained in a gel used for the management of asthma. METHODS: Thirty Sprague-Dawley rats were randomly divided into three equal groups using a random number table: the Feishu (BL 13) acupoint group, the Dazhui (GV 14) acupoint group, and the nonacupoint group or control group. Using microdialysis technology, preprocessed skin probes were implanted into the rats at Feishu (BL 13), Dazhui (GV 14), and a nonacupoint site. Asthma gel was then placed on the skin at Feishu (BL 13), Dazhui (GV 14) acupoints, and the nonacupoint for all groups. Dialysate was collected every 30 min for 12 h. The normalized concentration of sinapine thiocyanate in the skin was determined by high-performance liquid chromatography. RESULTS: The rat in vivo transdermal experiment demonstrated that the quantity-time equation showed a good linear correlation with zero-order kinetics (r > 0.99). The transdermal behavior was in accordance with the first-order rate open model in which the transdermal penetration rates and the accumulative amounts of sinapine thiocyanate in the skin at the acupoint sites were greater than those through the skin of the nonacupoint site. The systemic maximum concentration and the area under the curve of sinapine thiocyanate in the acupoint groups were significantly greater than in the nonacupoint group. A lag time was observed in both acupoint groups, but not in the nonacupoint group. CONCLUSION: Stimulating the acupoints promotes the percutaneous absorption of sinapine thiocyanate and also controls its release, reducing concentration fluctuations in the blood.

Optimization and evaluation of pluronic lecithin organogels as a transdermal delivery vehicle for sinomenine.

The purpose of the present study was to prepare and optimize sinomenine (SIN) pluronic lecithin organogels system (PLO), and to evaluate the permeability of the optimized PLO in vitro and in vivo. Box-Behnken design was used to optimize the PLO and the optimized formulation was pluronic F127 of 19.61%, lecithin of 3.60% and SIN of 1.27%. The formulation was evaluated its skin permeation and drug deposition both in vitro and in vivo compared with gel. Permeation and deposition studies of PLO were carried out with Franz diffusion cells in vitro and with microdialysis in vivo. In vitro studies, permeation rate (Jss) of SIN from PLO was 146.55 ± 2.93 µg/cm(2)/h, significantly higher than that of gel (120.39 µg/cm(2)/h) and the amount of SIN deposited in skin from the PLO was 10.08 ± 0.86 µg/cm(2), significantly larger than that from gel (6.01 ± 0.04 µg/cm(2)). In vivo skin microdialysis studies showed that the maximum concentration (Cmax) of SIN from PLO in "permeation study" and "drug-deposition study" were 150.27 ± 20.85 µg/ml and 67.95 µg/ml, respectively, both significantly higher than that of SIN from gel (29.66 and 6.73 µg/ml). The results recommend that PLO can be used as an advantageous transdermal delivery vehicle to enhance the permeation and skin deposition of SIN.

[Study on recovery and its influencing factors of ferulic acid and tetramethylpyrazine in cerebral microdialysis probe].

To establish a method for detecting microdialysis recovery of tetramethylpyrazine (TMP) and ferulic acid (FA) and investigating the influencing factors, providing the basis for further in vivo microdialysis experiments. The concentration of FA and TMP in dialysates were determined by high pressure liquid chromatography ( HPLC) and probe recovery were calculated respectively. The influence of the flow rates, medium concentration, temperature and in vivo probe stability on the recovery of FA and TMP were investigated by using concentration difference method (incremental method and decrement method). The recovery obtained by incremental method were similar to by decrement method. The in vitro recovery rate of FA and TMP decreased with the increase of 1-2.5 µL min(-1), and increased obviously with the temperature of 25-42 degrees C under the same conditions. The concentration of FA and TMP had no obvious effect on the probe recovery under the same flow rate. In addition, the recovery of TMP and FA remained stable and showed similar trends under the condition of four concentration cycles, indicating that the intra day reproducibility of the concentration difference method was good. The recovery of brain microdialysis probes in vivo 8 h maintained a relatively stable, but certain differences existed between different brain microdialysis probes, demonstrating that each probe was required for recovery correction in vivo experiment. Microdialysis sampling can be used for the local brain pharmacokinetic study of FA and TMP, and retrodialysis method can be used in probe recovery of FA and TMP in vivo.