Ningsheng Wang

Plasma pharmacokinetics and tissue distribution of [6]-gingerol in rats.

[6]‐Gingerol is one of the pungent components in ginger which has been found to possess various pharmacological effects. However, there is insufficient information on the properties of [6]‐gingerol based on controlled pharmacokinetic studies. The aim of this study was to clarify distribution profiles of [6]‐gingerol in blood and biological tissues of experimental rats. Rats were administered a 240 mg/kg dose of Gs (a ginger extract, containing 53% [6]‐gingerol) by oral ingestion. Plasma samples were collected at 2.5, 5, 7.5, 10, 15, 20, 30, 45 min, and 1, 1.5, 2, 3, 4 h after dosing (eight samples per time point), and brain, heart, lung, spleen, liver, kidney, stomach and small intestine tissues were collected at 5, 15, 30 min and 1, 2, 4 h after dosing (five animals per time point). Samples were prepared by a liquid‐liquid extraction procedure and the extracts were assayed by HPLC‐UV. After per oral application, [6]‐gingerol was absorbed rapidly into the plasma, and the maximal concentration (4.23 µg/ml) was reached after 10 min post dosing. [6]‐Gingerol plasma concentrations declined with time in a biexponential pattern. The elimination half‐time at the terminal phase was 1.77 h and the apparent total body clearance was 40.8 l/h. When administered orally, [6]‐gingerol was well distributed to the tissues examined, with the highest concentrations found in the gastrointestinal tract. Maximal concentrations of [6]‐gingerol were reached in most tissues at 0.5 h post‐dosing. The concentrations of [6]‐gingerol in tissues all were higher than in plasma with corresponding tissue to plasma ratios greater than 1 after 0.25 h post‐dose, showing high tissue partitioning and extensive distribution. Copyright

The Antithrombotic Effect of Borneol Related to Its Anticoagulant Property

Borneol is consumed excessively in China and Southeast Asian countries particularly in combined formula for preventing cardiovascular disease, but few studies were conducted on its effects on thrombosis. In this study, the antithrombotic and antiplatelet activities of borneol were investigated on thrombosis in vivo and on platelet aggregation ex-vivo. In addition, the coagulation parameters and influence on fibrinolytic activity were also assessed. The results showed that borneol had concentration dependent inhibitory effects on arterio-venous shunt and venous thrombosis but no effect on ADP and AA-induced platelet aggregation. Meanwhile, borneol prolonged the coagulation parameters for prothrombin time (PT) and thrombin time (TT), but did not show any fibrinolytic activity. It suggested that the antithrombotic activity of borneol and its action in combined formula for preventing cardiovascular diseases might be due to anticoagulant activity rather than antiplatelet activity.

Simultaneous determination of esculin and its metabolite esculetin in rat plasma by LC-ESI-MS/MS and its application in pharmacokinetic study.

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method operated in the negative electrospray ionization (ESI) switching mode has been developed and validated for the simultaneous determination of esculin and its metabolite esculetin in rat plasma. After addition of internal standards scopoletin, the plasma sample was pretreated by solid-phase extraction (SPE), and separated on a reversed phase C(18) column with a mobile phase of 0.01% formic acid in water (solvent A) and methanol (solvent B) using isocratic elution (A:B=20:80, v/v). The detection of target compounds was done in multiple reaction monitoring (MRM) mode. The MRM detection was operated in the negative ESI mode using the transitions of m/z 339.1 ([M-H](-))→176.7 for esculetin, m/z 176.9 ([M-H](-))→133.0 and m/z 191.0 ([M-H](-))→175.9 for scopoletin. The standard curves, which ranged from 25 to 3200 ng/mL for esculin with the lowest limit of quantification (LLOQ) of 0.25 ng/mL and from 1.25 to 160 ng/mL for esculetin with the LLOQ of 1.25 ng/mL, were fitted to a 1/x weighted quadratic regression model. The method also afforded satisfactory results in terms of the sensitivity, specificity, precision (intra- and inter-day, RSD<8.73%), accuracy, recovery as well as the stability of the analyte under various conditions. The method was successfully applied to study the pharmacokinetics of esculin and its metabolite esculetin in rat plasma after oral administration of esculin at a dose of 100mg/kg.

Pharmacokinetics of ferulic acid and potential interactions with Honghua and clopidogrel in rats

AIM OF THE STUDY Ferulic acid (FA), a compound isolated from herbs, has a big potential to be developed into a useful drug for the treatment of cardiovascular disease. Early estimation of potential drug interaction is critical for drug development. As a common Chinese herb and Western drug respectively, Honghua and clopidogrel are often combined with FA-containing herbs to treat cardiovascular disease in clinical practice. This study aimed to investigate the pharmacokinetics of FA and potential interaction with Honghua and clopidogrel in rats. MATERIALS AND METHODS The experiments were performed on following three groups: FA alone (10mg/kg, P.O.), combination of FA and Honghua (700 mg/kg, P.O.), combination of FA and clopidogrel (7 mg/kg, P.O.). Blood samples were collected before dosing and at 0, 2, 4, 7, 10, 15, 20, 30, 45, 60, 90, 120, 150, 180 and 210 min after drug administration to determine the plasma drug concentration of FA. RESULTS FA was rapidly absorbed following oral administration with a mean time to peak plasma concentration (T(max)) of 0.03 h. The corresponding maximum plasma concentration (C(max)) and the area under the concentration-time curve (AUC) were 8174.55 ng/L and 2594.45 h ng/mL respectively. Coadministration of Honghua and clopidogrel resulted in a 63.5% and 79.7% increase in the AUC respectively. The C(max) of FA was significantly increased by coadministration with clopidogrel (74.3%, p<0.01). Moreover, the T(max) of FA when coadministered with Honghua or clopidogrel was 3 and 3.76 times slower than when administered alone. Other pharmacokinetic parameters estimated for FA were also altered by the coadministrations, but no statistically significant differences were observed. CONCLUSION FA was rapidly absorbed with a low bioavailability after a single oral administration. The pharmacokinetics profile of FA in rats was partly altered by the coadministration of FA with Honghua or clopidogrel.

Antithrombotic effects of Danggui, Honghua and potential drug interaction with clopidogrel.

AIM OF THE STUDY The antithrombotic effect of Danggui and Honghua, herbs commonly used in Traditional Chinese medicine to treat the syndrome corresponding to vascular thrombosis, and their potential interactions with clopidogrel were investigated. MATERIALS AND METHODS The efficacy of Danggui, Honghua alone or combination with clopidogrel was determined in three experimental models. Bleeding time and hematology parameters were measured to evaluate safety. RESULTS Danggui and Honghua exhibited antithrombotic effects against venous thrombosis and pulmonary embolism. Especially in the case of venous thrombosis, the thrombus weight was decreased significantly by Danggui or Honghua when compared with control. Bleeding time and coagulation time tended to be prolonged by Danggui or Honghua, but only prothrombin time (PT) and thrombin time (TT) were augmented significantly. The combinations of Danggui plus clopidogrel and of Honghua plus clopidogrel failed to significantly enhance the antithrombotic effects of clopidogrel alone against arterial thrombosis, venous thrombosis and pulmonary embolism. However, both Danggui and Honghua significantly potentiated the prolongation caused by clopidogrel on the tail bleeding time and PT. CONCLUSIONS Danggui and Honghua possess antithrombotic activity and cannot potentiate the antithrombotic effect of clopidogrel. However, they significantly enhance the deleterious effect of clopidogrel on bleeding time, PT and TT.

Can Chinese Herbal Medicine Adjunctive Therapy Improve Outcomes of Senile Vascular Dementia? Systematic Review with Meta-analysis of Clinical Trials.

Many publications have reported the growing application of complementary and alternative medicine, particularly the use of Chinese herbal medicine (CHM) in combination with routine pharmacotherapy (RP) for senile vascular dementia (SVD), but its efficacy remains largely unexplored. The purpose of this study is to evaluate the efficacy of CHM adjunctive therapy (CHMAT), which is CHM combined with RP, in the treatment of SVD. Publications in seven electronic databases were searched extensively, and 27 trials with a total of 1961 patients were included for analysis. Compared with RP alone, CHMAT significantly increased the effective rate [odds ratio (OR) 2.98, 95% confidence interval (CI) 2.30, 3.86]. In addition, CHMAT showed benefits in detailed subgroups of the Mini‐Mental State Exam (MMSE) score from time of onset to 4 weeks (WMD 3.01, 95% CI 2.15, 3.87), 8 weeks (weighted mean difference (WMD) 2.30, 95% CI 1.28, 3.32), 12 weeks (WMD 2.93, 95% CI 2.17, 3.69), and 24 weeks (WMD 3.25, 95% CI 2.61, 3.88), and in the activity of daily living scale score from time of onset to 4 weeks (WMD −4.64, 95% CI −6.12, −3.17), 8 weeks (WMD −4.30, 95% CI −6.04, −2.56), 12 weeks (WMD −3.89, 95% CI −4.68, −3.09), and 24 weeks (WMD −4.04, 95% CI −6.51, −1.57). Moreover, CHMAT had positive effects on changes in the Hasegawa dementia scale, National Institutes of Health Stroke Scale, Clinical Dementia Rating, and Montreal Cognitive Assessment scores, as well as blood fat levels (total cholesterol, triglyceride, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, and apolipoprotein E), platelet aggregation rate (1‐min platelet aggregation rate, 5‐min platelet aggregation rate, and maximal platelet aggregation rate), and blood rheology (whole‐blood viscosity and hematocrit). No serious or frequently occurring adverse effects were reported. Weaknesses of methodological quality in most trials were assessed using the Cochrane risk of bias tool, while the quality level of Grades of Recommendations Assessment Development and Evaluation (GRADE) evidence classification indicated ‘very low’. This systematic review suggests that CHM as an adjunctive therapy can improve cognitive impairment and enhance immediate response and quality of life in SVD patients. However, because of limitations of methodological quality in the included studies, further research of rigorous design is needed. Copyright

Pharmacokinetics of dihydroartemisinin in Artekin tablets for single and repeated dosing in Chinese healthy volunteers

Aim. To study the pharmacokinetics of dihydroartemisinin (DHA) in Artekin (compound dihydroartemisinin) tablets in Chinese healthy volunteers. Methods. Eighteen healthy volunteers (9 males, 9 females) received Artekin tablets for oral administration. The plasma samples of DHA were analysed by liquid–liquid extraction and determined by HPLC/ESI/MS. Results. The plasma DHA concentration–time curves of single dose and repeated doses of DHA were fitted to a two‐compartment open model. The mean pharmacokinetic parameters of DHA in a single dose were: t1/2(β)=1.245 ± 0.495 h, Cmax=243.6 ± 56.15 µg/l, AUC0 → ∞=450 ± 69 h × µg/l, Vd=5.75 ± 2.2 l/kg and Cl=3.245 ± 0.38 l/h/kg, while in repeated doses they were: t1/2(β)=1.085 ± 0.298 h, AUC0 → ∞=444.35 ± 80.43 h × ng/ml, Vd=4.62 ± 1.128 ml/kg, Cl=3.0125 ± 0.875 ml/h/kg, respectively. Conclusion. The study showed that DHA in Artekin was rapidly absorbed, distributed and eliminated in the healthy subjects. The pharmacokinetic properties of DHA in Artekin were not affected by gender in a single dose. While in repeated doses accumulation of DHA did not appear after repeated doses. Copyright

Geniposidic acid protected against ANIT-induced hepatotoxity and acute intrahepatic cholestasis, due to Fxr-mediated regulation of Bsep and Mrp2.

ETHNOPHARMACOLOGICAL RELEVANCE Geniposidic acid (GPA) is the main constituent of Gardenia jasminoides Ellis (Rubiaceae), which has long been used to treat inflammation, jaundice and hepatic disorders. The cholagogic effect of Gardenia jasminoides Ellis (Rubiaceae) and GPA have been widely reported, but the underlying occurrence mechanism remains unclear. AIM OF THE STUDY This investigation was designed to evaluate the hepatoprotection effect and potential mechanisms of GPA derived from Gardenia jasminoides Ellis (Rubiaceae) on fighting against α-naphthylisothiocyanate (ANIT) caused liver injury with acute intrahepatic cholestasis. MATERIALS AND METHODS Sprague-Dawley (SD) rats were intragastrically (i.g.) administered with the GPA (100, 50 and 25mg/kg B.W. every 24h) for seven consecutive days, and then they were treated with ANIT (i.g. 65mg/kg once in the 5th day) which induced liver injury with acute intrahepatic cholestasis. Serum and bile biochemical analysis, bile flow rate and liver histopathology were measured to evaluate the protective effect of GPA fight against ANIT treatment. The protein and mRNA expression levels of farnesoid X receptor (Fxr), bile-salt export pump (Bsep), multidrug resistance associated protein2 (Mrp2), were evaluated to study the effect of liver protection about GPA against ANIT induced hepatotoxicity and underlying mechanisms. RESULTS Some abnormalities were observed on ANIT treated rats including weight loss, reduced food intake and hair turned yellow. Obtained results demonstrated that at dose 100 and 50mg/kg B.W. (P<0.01) and 25mg/kg B.W. (P<0.05) of GPA pretreated dramatically prevented ANIT induced decreased in bile flow rate. Compared with ANIT treated group, the results of bile biochemical parameters about total bile acid (TBA) was increased by GPA at groups with any dose (P<0.01), glutathione (GSH) was increased significantly at high dose (P<0.01) and medium dose (P<0.05), total bilirubin (TB) was increased at high and medium dose (P<0.05), direct bilirubin (DB) was only increased at high dose (P<0.01). Serum levels of glutamic-Oxalacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), γ-glutamyltranspeptidase (γ-GT), TB, DB and TBA in comparison with ANIT treated group (P<0.01) were reduced by GPA (between 100 and 50mg/kg B.W.) pretreatment. Histopathology of the liver tissue showed that pathological damages and hepatic portal area filled with bile were relieved after GPA pretreatment compared with ANIT treated group. The protein and mRNA expression of Fxr, Bsep and Mrp2 were decreased in ANIT treated group. On the contrary, the protein and mRNA of Fxr, Bsep and Mrp2 were up regulated significantly pretreatment by GPA at dose of high and medium groups. On protein level of Bsep and Mrp2 the result shown no statistical difference in GPA (25mg/kg B.W.), but it was not same shown in mRNA level. CONCLUSION The results of this investigation have demonstrated that the GPA exerts a dose dependent hepatoprotection effect on ANIT induced liver damage with acute intrahepatic cholestasis in rats, which may due to Fxr mediated regulation of bile transporters like Bsep and Mrp2.

Determination of geniposidic acid in rat plasma by LC-MS/MS and its application to in vivo pharmacokinetic studies.

A simple, rapid and sensitive method for the determination of geniposidic acid (GSA) in rat plasma was developed using liquid chromatography tandem mass spectrometry (LC-MS/MS). Geniposide (GS) was used as the internal standard. Rat plasma pretreated by solid-phase extraction (SPE) was analyzed by LC-MS/MS with negative ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The analytical column was C₈ column and the mobile phase was methanol (A) and water (B). The flow rate was set at 0.8 mL/min with split ratio of 1:3, the total run time was 15 min. The MS/MS ion transitions monitored were m/z 373.3-211.1 for GSA and m/z 387.3-225.3 for GS. The quantification limit was 5 ng/mL within a linear range of 10-4000 ng/mL. The inter-day and intra-day accuracy and precision were within ±10%. The method was fully validated for its sensitivity, selectivity, matrix effect, stability study and recovery. The data indicate that our LC-MS/MS assay is an effective method for the pharmacokinetics study of GSA in rat plasma.

Effect of Danggui and Honghua on Cytochrome P450 1A2, 2C11, 2E1 and 3A1 mRNA Expression in Liver of Rats

As alternative medicines or dietary supplements, herbal medicines have received increasing interest in recent years. Danggui and Honghua are two of the most popular traditional Chinese herbal medicines. However, little is known about the pharmacokinetics interactions between Danggui/Honghua and prescription drugs. Therefore, the present study was undertaken to investigate the effect of Danggui or Honghua on the gene expression of cytochrome P450 (CYP) using reverse- transcriptase-polymerase chain reaction (RT-PCR) in Wistar rats. Commercial Danggui (0.35 and 0.7 g/kg, twice a day), Honghua (0.35 g/kg or 0.7 g/kg, twice a day) or water (control group) were given to rats (3 rats for each group) for 5 consecutive days. Treatment of rats with 0.7 and 1.4 g/kg per day Danggui or Honghua for 5 days caused mild to strong increase of CYP 3A1 and decrease of CYP 2E1 RNA expression. However, only Honghua (0.7 and 1.4 g/kg per day) induced the increase of CYP 1A2 RNA expression, while CYP 2C11 RNA was unaffected by both Danggui and Honghua. These data demonstrated that Danggui or Honghua affected the expression of hepatic CYP isoforms in the rats; they elevated CYP 1A2 and 3A1 RNA expression but inhibited CYP 2E1 RNA expression. Such alterations may change the therapeutic actions of the drugs metabolized primarily by P450 system when they are co-administered to people with Danggui or Honghua. Therefore, patients should be cautioned about the potential drug-herb interactions between Danggui or Honghua and prescription drugs that were metabolized by CYP1A2, 2E1 and 3A1 isoforms.