Improving cellular uptake and synergetic anti-tumor effects of magnolol and Brucea javanica oil through self-microemulsion.

OBJECTIVE: Magnolol (MG) and Brucea javanica (L.) Merr. oil (BJO) possess synergetic anti-tumor effects, but have poor water solubility and stability, which results in low oral bioavailability. SIGNIFICANCE: The MG loaded self-microemulsion drug delivery system (MG-SMDDS) with BJO as oil phase component was utilized to improve the cellular uptake and synergetic anti-tumor effects. METHODS: Compatibility study and pseudoternary phase diagram (PTPD) were respectively employed to screen for the composition and proportion of oil phase in the formulation. Central composite design-effect surface method was applied to optimize proportion of each formulation condition. The droplet size, ζ-potential, colloid stability, encapsulation rate (ER) and in vitro dissolution rate of MG-SMDDS were evaluated. Furthermore, cellular uptake and cytotoxicity of the microemulsion on HepG2 cells were assessed. RESULTS: The optimal composition of MG-SMDDS was: MG (9.09%), castor oil (7.40%), BJO (2.47%), Cremophor EL 35 (54.04%) and 1, 2-propanediol (27.01%). The MG-SMDDS exhibited satisfactory droplet size, ζ-potential, colloid stability and ER, as well as faster dissolution rate than free MG. More importantly, SMEDDS containing BJO could enhance the cellular uptake and cytotoxicity of free BJO and free MG on tumor cells. CONCLUSIONS: The BJO self-microemulsion delivery technique can provide an idea for design of oral delivery vehicles based on BJO.

Comparative pharmacokinetic study of six lignans in normal and diabetic rats after oral administration of Saururus chinensis extract by LC-MS/MS.

Saururus chinensis (SC) possesses significant anti-diabetic activity and lignans were its major bioactive compounds. In this study, a rapid and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was established for simultaneous quantification of six lignans, namely (-)-(7R,8R)-machilin D (1), verrucesin (2), rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan (3), manassantin A (4), manassantin B (5), and saucerneol F (6) in rat's plasma. It was validated with acceptable linearity (r ≥ 0.9922), accuracy (80.42-95.17%), precision (RSD ≤ 12.08%), and extraction recovery (80.36-93.45%). The method was successfully applied to the comparative pharmacokinetic study of the six lignans in normal and diabetic rats after oral administration of SC extract. Results showed that the areas under the plasma concentration-time curve (AUC0 → t and AUC0 → ∞ ) of (-)-(7R,8R)-machilin D, rel-(7S,8S,7'R,8'R)-3,3',4,4',5,5'-hexamethoxy-7.O.7',8.8'-lignan, manassantin B, and saucerneol F in diabetic rats were significantly increased, and the plasma clearance (CL) of (-)-(7R,8R)-machilin D in diabetic rats was significantly decreased. However, the AUC0 → t and AUC0 → ∞ of verrucesin were significantly decreased, and its CL was significantly increased in diabetic rats compared with those in normal rats. These results indicated that there were remarkable differences in the pharmacokinetic parameters between the normal and diabetic rats. The pharmacokinetic studies might be beneficial for the clinical use of SC as hypoglycemic agent.

Determination of myrislignan levels in BALB/c mouse plasma by LC-MS/MS and a comparison of its pharmacokinetics after oral and intraperitoneal administration.

BACKGROUND: Myrislignan is a natural product from Myristica sp. with diverse pharmacological activities. Recently, the anti-Toxoplasma gondii (T. gondii) activity of myrislignan has been proposed, and in vivo studies of its pharmacokinetics in BALB/c mice are necessary to further evaluate the clinical effects of myrislignan. RESULTS: In this study, a sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to quantify myrislignan levels in mouse plasma using dehydrodiisoeugenol as an internal standard (IS) in positive ion mode. Chromatographic separation of the analytes was achieved using an ACE Ultracore Super C18 analytical column (2.5 µm, 2.1 × 50 mm) at 30 °C. A gradient mobile phase consisting of water (0.1 % formic acid) and acetonitrile (0.1 % formic acid) was delivered at a flow rate of 0.4 mL/min. Myrislignan and the IS eluted at 1.42 and 1.71 min, respectively. A good excellent linear response across the concentration range of 1-1000 ng/mL was achieved (r2 = 0.9973). The lower limit of quantification (LLOQ) was 1 ng/mL, and the inter- and intra-day accuracy and precision of the method showed relative standard deviations (RSDs) less than 10 %. The method was applied to examine the pharmacokinetics of myrislignan in mouse plasma following a single oral administration of 200 mg/kg or intraperitoneal administration of 50 mg/kg myrislignan, and the bioavailability (F) of orally administered myrislignan was only 1.97 % of the bioavailability of intraperitoneally administered myrislignan. CONCLUSIONS: A rapid and sensitive LC-MS/MS method has been was developed, validated and successfully used to determine myrislignan levels in mice after oral or intraperitoneal administration. This study is the first to report the pharmacokinetic parameters of myrislignan in mice and to compare its pharmacokinetics after oral and intraperitoneal administration, which will be useful for further research on the administration of myrislignan in animals and humans.

Simultaneous determination of asarinin, ß-eudesmol, and wogonin in rats using ultraperformance liquid chromatography-tandem mass spectrometry and its application to pharmacokinetic studies following administration of standards and Gumiganghwal-tang.

Asarinin, ß-eudesmol, and wogonin have common antiangiogenic activities and have the potential for use in chemotherapy. Besides, they are multivalent substances that are combined in various herbal medicines. The purpose of this study was to develop a method for simultaneous analysis of asarinin, ß-eudesmol, and wogonin, which are representative pharmacological components of Asarum heterotropoides, Atractylodes lancea, and Scutellaria baicalensis, respectively, in rat biosamples using ultraperformance liquid chromatography-tandem mass spectrometry. The three components were separated using 5 mm aqueous ammonium acetate containing 0.1% formic acid and acetonitrile as a mobile phase, equipped with a KINETEX core-shell C18 column. The analysis was quantitated on a triple-quadrupole mass-spectrometer employing electrospray ionization, and operated in the multiple reaction monitoring mode. The chromatograms showed high resolution, sensitivity, and selectivity with no interference with plasma, urine, and feces constituents. The developed analytical method satisfied international guidance criteria and could be successfully applied to the pharmacokinetic (PK) studies evaluating oral bioavailability of asarinin, ß-eudesmol, and wogonin after oral and intravenous administration and their urinary and fecal excretion ratios after oral administration to rats. Furthermore, the analysis was extended to PK studies following oral administration of Gumiganghwal-tang. This study was the first simultaneous analysis of the aforesaid three constituents in rat plasma, urine, and feces that also determined their PK parameters.

Simultaneous determination of eight bioactive constituents of Zhi-Zi-Hou-Po decoction in rat plasma by ultra high performance liquid chromatography with tandem mass spectrometry and its application to a pharmacokinetic study.

Zhi-Zi-Hou-Po Decoction, consisting of Gardenia jasminoides Ellis, Magnolia officinalis Rehd. et Wils., and Citrus aurantium L, is a classical Traditional Chinese Medicine formula for the treatment of depression. In order to make good and rational use of this formula in the future, a sensitive, selective, and reliable ultra high performance liquid chromatography with tandem mass spectrometry method was developed for simultaneous determination of two iridoid glycosides (geniposide and genipin gentiobioside), two lignans (honokiol and magnolol), four flavonoid glycosides (isonaringin, naringin, hesperidin, and neohesperidin), the major bioactive constituents of Zhi-Zi-Hou-Po Decoction, in rat plasma using paeoniflorin as internal standard. Plasma samples were pretreated by a simple protein precipitation with acetonitrile. Chromatographic separation was performed on a shim-pack XR-ODS C18 column (75 × 3.0 mm, 2.2 µm) using gradient elution with mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile at a flow rate of 0.5 mL/min. Mass spectrometric detection was conducted on a 3200 QTRAP mass spectrometry equipped with electrospray ionization source in negative ionization mode. Quantification was performed using multiple reactions monitoring mode. Calibration curves exhibited good linearity (r > 0.9947) over a wide concentration range for all analytes, and the lower limits of quantification were 10, 5, 1, 5, 1, 5, 1, and 5 ng/mL for geniposide, genipin gentiobioside, honokiol, magnolol, isonaringin, naringin, hesperidin, and neohesperidin, respectively. The intraday and interday precisions at three quality control levels were less than 12.3% and the accuracies ranged from -11.2 to 10.7%. Extraction recovery, matrix effect, and stability were satisfactory in rat plasma. The validated method was successfully applied to a pharmacokinetic study of the eight analytes after oral administration of Zhi-Zi-Hou-Po decoction to rats.

Comparative absorption kinetics of seven active ingredients of Eucommia ulmoides extracts by intestinal in situ circulatory perfusion in normal and spontaneous hypertensive rats.

Eucommia ulmoides Oliv. (E. ulmoides) is a valuable and nourishing medicinal herb in China that has been used in the treatment of hypertension. Given the fact that most traditional Chinese medicine is mainly used to treat disease, investigating the pharmacokinetics of traditional Chinese medicines in the pathological state is more useful than that in the normal state. However, the differences in the absorption kinetics of active ingredients of E. ulmoides extract between pathological and physiological conditions have not been reported. Therefore, in this study, the rat intestinal in situ circulatory perfusion model was used to investigate the differences in absorption kinetics of seven active ingredients of E. ulmoides extract in normal and spontaneously hypertensive rats, namely, genipinic acid, protocatechuic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, (+)-pinoresinol di-O-ß-D-glucopyranoside and (+)-pinoresinol 4'-O-ß-D-glucopyranoside. Our results indicate that the pathological state of spontaneous hypertension may change the absorption of active components of E. ulmoides extracts, and these findings may provide a reference for improving the rational use of E. ulmoides in the clinic.

Self-Nanoemulsifying Drug Delivery Systems for Enhancing Solubility, Permeability, and Bioavailability of Sesamin.

Sesamin (SSM) is a water-insoluble compound that is easily eliminated by liver metabolism. To improve the solubility and bioavailability of SSM, this study developed and characterized a self-nanoemulsifying drug delivery system (SNEDDS) for the oral delivery of SSM and conducted pharmacokinetic assessments. Oil and surfactant materials suitable for SNEDDS preparation were selected on the basis of their saturation solubility at 37 ± 0.5 °C. The mixing ratios of excipients were determined on the basis of their dispersibility, transmittance (%), droplet sizes, and polydispersity index. An SNEDDS (F10) formulation comprising glyceryl trioctanoate, polyoxyethylene castor oil, and Tween 20 at a ratio of 10:10:80 (w/w/w) was the optimal formulation. This formulation maintained over 90% of its contents in different storage environments for 12 weeks. After the self-emulsification of SNEDDS, the SSM dispersed droplet size was 66.4 ± 31.4 nm, intestinal permeability increased by more than three-fold, relative bioavailability increased by approximately 12.9-fold, and absolute bioavailability increased from 0.3% to 4.4%. Accordingly, the developed SNEDDS formulation can preserve SSM's solubility, permeability, and bioavailability. Therefore, this SNEDDS formulation has great potential for the oral administration of SSM, which can enhance its pharmacological application value.

Inhibitory effect of sesamin on ivabradine metabolism in rats.

In this work, the aim of our study was to assess whether sesamin could influence the pharmacokinetics of ivabradine and its active metabolite N-desmethylivabradine in rats. At the begining, 12 healthy male Sprague-Dawley rats were randomly divided into two groups: The rats were received an oral administration of 1.0mg/kg ivabradine alone (the control group), and the rats were given 1.0mg/kg ivabradine co-administered with 50mg/kg sesamin by gavage (the test group). After that, blood samples were collected from the tail vein of rats, and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) were used for determing the plasma concentrations of ivabradine and N-desmethylivabradine in rats. Finally, the pharmacokinetic parameters were estimated using DAS 2.0 software. As the results, the pharmacokinetic parameters (t1/2, Cmax, AUC (0-t) and AUC (0-oo)) of ivabradine in the control group were significantly lower than those in the test group (P<0.05). Moreover, sesamin significantly decreased t1/2, Cmax, AUC(0-t) and AUC(0-oo) of N-desmethylivabradine when compared to the control. These results demonstrated that sesamin increases plasma concentration of ivabradine and decreases N-desmethylivabradine conversely. Hence, our data indicated sesamin could influence the pharmacokinetic profile of ivabradine in rats, which might cause food-drug interaction in humans.

In vitro metabolism of magnolol and honokiol in rat liver microsomes and their interactions with seven cytochrome P substrates.

RATIONALE: Magnolol and honokiol are the main active components of Magnolia officinalis Rehd. et Wils. The study of their interactions with liver microsomes is very important for the clinical safety of M. officinalis Rehd. et Wils. METHODS: The main metabolites of magnolol and honokiol in rat liver microsomes were investigated using ultrahigh-performance liquid chromatography/mass spectrometry and their possible structures were identified. In addition, cytochrome P450 (CYP450) isoenzymes of the major rat metabolites of magnolol and honokiol were identified using a specific inhibitor. RESULTS: This study suggests that the CYP2E1 subtype is responsible for the oxidation of magnolol and honokiol terminal double bonds to epoxy metabolites. CYP3A4 appears to be the major subtype responsible for further hydrolytic metabolism, while CYP1A2 may promote decarboxylation of the metabolites. CYP2A6 may be the main subtype responsible for the hydrogenation of magnolol (p < 0.05). CONCLUSIONS: This study demonstrated that different CYP450 enzyme isoforms showed different activities in the in vitro metabolism of magnolol and honokiol in rat liver microsomes. It has certain practical applications in that we should pay attention to drug-drug interactions in clinical medications and also to drug-enzyme interactions.

Pharmacokinetics and distribution of schisandrol A and its major metabolites in rats.

1. Schizandrol A is an active component in schisandra, also the representative component for the identification of schisandra. 2. A rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry (RRLC-QTOF/MS) was developed to investigate the pharmacokinetics of schizandrol A after its intragastric administration (50 mg/kg) in rats. 3. Schizandrol A was rapidly absorbed (T max = 2.07 h), with a longer duration (t 1/2 = 9.48 h) and larger apparent volume of distribution (Vz/F = 111.81 l/kg) in rats. Schizandrol A can be detected in main organs and the order of its distribution was in the liver > kidney > heart > spleen > brain, particularly higher in the liver. 4. Five schizandrol A metabolites were identified, including 2-demethyl-8(R)-hydroxyl-schizandrin, 3-demethyl-8(R)-hydroxyl-schizandrin, hydroxyl-schizandrin, demethoxy-schizandrin, 2, 3-demethyl-8(R)-hydroxyl-schizandrin, indicating that the hydroxylation and demethylation may be the major metabolic way of schizandrol A. 5. This study defined the pharmacokinetic characteristics of schizandrol A in vivo, and the RRLC-QTOF/MS is more sensitive and less limited by conditions, and needs less samples, which may be a useful resource for the further research and development of schisandrol A.

Interaction of deoxyschizandrin and schizandrin B with liver uptake transporters OATP1B1 and OATP1B3.

1. Deoxyschizandrin and schizandrin B have diverse pharmacological effects, including hepatoprotective activity. We aim to study their hepatic uptake and their effects on the hepatic uptake of other clinical drugs mediated by OATP1B1 and OATP1B3. 2. Deoxyschizandrin exhibited a high affinity for OATP1B1 with Km of 17.61 ± 0.43 µM but a low affinity for OATP1B3. Similarly, schizandrin B also showed a strong affinity for OATP1B1 with Km of 18.45 ± 1.23 µM but a weak affinity for OATP1B3. 3. Atorvastatin and rifampicin could inhibit the uptake of deoxyschizandrin and schizandrin B mediated by OATP1B1. 4. Intriguingly, both deoxyschizandrin and schizandrin B significantly promoted the uptake of atorvastatin (with EC50 of 50.58 ± 8.08 and 24.70 ± 5.82 µM, respectively) and rosuvastatin (with EC50 of 13.46 ± 2.70 and 8.99 ± 4.73 µM, respectively) mediated by OATP1B1. Deoxyschizandrin could markedly promote the uptake of fluvastatin but inhibit the uptake of sodium taurocholate (TCNa) mediated by OATP1B1. 5. The promotion on hepatic uptake of statins mediated by OATP1B1 might lead to enhanced efficacy of cholesterol lowering and reduced risk of myopathy for hyperlipidemia patients when given statins together with deoxyschizandrin or schizandrin B.

Comparative pharmacokinetic study of four major bioactive components after oral administration of Zhi-Zi-Hou-Po decoction in normal and corticosterone-induced depressive rats.

A highly selective and efficient LC-MS/MS method was developed to determine the plasma concentration of magnolol, hesperidin, neohesperidin and geniposide following oral administration of Zhi-Zi-Hou-Po decoction in normal and depressed rats. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an XTerra® MS C18 column using a gradient elution with a mobile phase composed of acetonitrile-0.1% aqueous formic acid. The proposed method was validated to be specific, accurate and precise for the analytes determination in plasma samples. The calibration curves displayed good linearity over definite concentration ranges for the analytes. The intra- and inter-day precision of the proposed method at three different levels were all within <11.13% and the relative errors ranged from -8.46 to 8.93%. The recovery of the four compounds ranged from 82.72 to 89.08% and no apparent matrix effect was observed during sample analysis. After full validation, the established method was successfully applied for comparing the pharmacokinetics of four components between normal and depressed rats. The results showed that the AUC and Cmax of four analytes in depressed rats were significantly different from those in normal rats and might provide helpful information to guide the clinical use of Zhi-Zi-Hou-Po to treat depression.

Pharmacokinetics and liver uptake of three Schisandra lignans in rats after oral administration of liposome encapsulating ß-cyclodextrin inclusion compound of Schisandra extract.

Schisandra chinensis fructus (SCF) is widely used traditional Chinese medicine, which possesses hepato-protective potential. Schisandrin (SD), schisantherin (ST), and γ-schizandrin (SZ) are the major bioactive lignans. The main problem associated with the major bioactive lignans oral administration is low oral bioavailability due to the lignans' poor aqueous solubility and taste. The aim of the present research work was to develop liposome (SCL) encapsulated ß-cyclodextrin (ß-CD) inclusion complex loaded with SCF extract (SCF-E). The SD, ST, and SZ were selected as effective candidates to perform comparisons of liver targeting among the solution (SES), ß-cyclodextrin inclusion compound (SCF-E-ß-CD), liposome (SEL), and SCL of SCF-E to characterize the pharmacokinetic behaviors and liver targeting in rats. The ß-CD inclusion complex (SCF-E-ß-CD) was used to improve the solubility. The concentrations were determined using high-performance liquid chromatography (HPLC) and analyzed by DAS3.0. The pharmacokinetic results indicate that the plasma concentration-time courses were fitted well to the one-compartment model with the first weighing factor. The half-life period (t1/2) and area under the concentration-time curve (AUC) of the three components in SCL were the largest. The SCL exhibit a relatively high liver targeting effect. The results would be helpful for guiding the clinical application of this herbal medicine.

A Rapid UPLC-MS Method for Quantification of Gomisin D in Rat Plasma and Its Application to a Pharmacokinetic and Bioavailability Study.

Gomisin D, a lignan compound isolated from Fructus Schisandra, is a potential antidiabetic and anti-Alzheimer's agent. Recently, gomisin D was used as a quality marker of some traditional Chinese medicine (TCM) formulas. In this study, a rapid ultra-performance liquid chromatography/tandem mass spectrometry method (UPLC-MS/MS) was developed and validated to quantify gomisin D in rat plasma for a pharmacokinetic and bioavailability study. Acetonitrile was used to precipitate plasma proteins. Separations were performed on a BEH C18 column with a gradient mobile phase comprising of acetonitrile and water (0.1% formic acid). An electrospray ionization source was applied and operated in the positive ion mode. The multiple reaction monitoring mode (MRM) was utilized to quantify gomisin D and nomilin (internal standard, IS) using the transitions of m/z 531.2 → 383.1 and m/z 515.3 → 161.0, respectively. The calibration curve was linear over the working range from 1 to 4000 ng/mL (R² = 0.993). The intra- and interday precision ranged from 1.9% to 12.9%. The extraction recovery of gomisin D was in the range of 79.2-86.3%. The validated UPLC-MS/MS method was then used to obtain the pharmacokinetic characteristics of gomisin D after intravenous (5 mg/kg) and intragastric (50 mg/kg) administration to rats. The bioavailability of gomisin D was 107.6%, indicating that this compound may become a promising intragastrical medication. Our results provided useful information for further preclinical studies on gomisin D.

Pharmacokinetics and Tissue Distribution of Anwuligan in Rats after Intravenous and Intragastric Administration by Liquid Chromatography-Mass Spectrometry.

Anwuligan, a natural 2,3-dibenzylbutane lignan from the nutmeg mace of Myristica fragans, has been proved to possess a broad range of pharmacological effects. A rapid, simple, and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been established and successfully applied to the study of pharmacokinetics and tissue distribution of anwuligan after intravenous or intragastric administration. Sample preparation was carried out through a liquid-liquid extraction method with ethyl acetate as the extraction reagent. Arctigenin was used as the internal standard (IS). A gradient program was employed with a mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile. The mass spectrometer was operated in a positive ionization mode with multiple reaction monitoring. The transitions for quantification were m/z 329.0→205.0 for anwuligan and m/z 373.0→137.0 for IS, respectively. Calibration curves were linear over the ranges of 0.5-2000 ng/mL for both plasma samples and tissue samples (r > 0.996). The absolute bioavailability is 16.2%, which represented the existing of the obvious first-pass effect. An enterohepatic circulation was found after the intragastric administration. Anwuligan could be distributed rapidly and widely in different tissues and maintained a high concentration in the liver. The developed and validated LC-MS/MS method and the pharmacokinetic study of anwuligan would provide reference for the future investigation of the preclinical safety of anwuligan as a candidate drug.

Overview of the anti-inflammatory effects, pharmacokinetic properties and clinical efficacies of arctigenin and arctiin from Arctium lappa L.

Arctigenin (AR) and its glycoside, arctiin, are two major active ingredients of Arctium lappa L (A lappa), a popular medicinal herb and health supplement frequently used in Asia. In the past several decades, bioactive components from A lappa have attracted the attention of researchers due to their promising therapeutic effects. In the current article, we aimed to provide an overview of the pharmacology of AR and arctiin, focusing on their anti-inflammatory effects, pharmacokinetics properties and clinical efficacies. Compared to acrtiin, AR was reported as the most potent bioactive component of A lappa in the majority of studies. AR exhibits potent anti-inflammatory activities by inhibiting inducible nitric oxide synthase (iNOS) via modulation of several cytokines. Due to its potent anti-inflammatory effects, AR may serve as a potential therapeutic compound against both acute inflammation and various chronic diseases. However, pharmacokinetic studies demonstrated the extensive glucuronidation and hydrolysis of AR in liver, intestine and plasma, which might hinder its in vivo and clinical efficacy after oral administration. Based on the reviewed pharmacological and pharmacokinetic characteristics of AR, further pharmacokinetic and pharmacodynamic studies of AR via alternative administration routes are suggested to promote its ability to serve as a therapeutic agent as well as an ideal bioactive marker for A lappa.

Study on the pharmacokinetics of deoxyschizandrin and schizandrin in combination with epigallocatechin gallate, a component of green tea, in rats.

1. Green tea is commonly used worldwide due to its potential positive health benefits. We have examined the effects of epigallocatechin gallate (EGCG), the most abundant catechin in green tea, on the pharmacokinetics of deoxyschizandrin (DSD) and schizandrin (SD), which are the representative lignans in popular traditional Chinese medicines Fructus schisandrae, in rats. 2. The effects on the transport in Caco-2 cells and metabolism in human liver microsomes (HLMs) of DSD and SD by EGCG were determined to analyze their interactions thoroughly. 3. In pharmacokinetic studies, rats were divided into four groups. Each group was orally treated with DSD alone (Group 1), DSD combined with EGCG (Group 2), SD alone (Group 3) and SD combined with EGCG (Group 4). The pharmacokinetic parameters of DSD and SD in rats were determined by UPLC-MS/MS. 4. The in vivo results indicated that EGCG had no significant influence on the pharmacokinetic behaviors of DSD or SD in rats, which were in accordance with the in vitro transport and metabolism studies. However, there were marked differences between male and female rats among Cmax, AUC0-t, AUC0-∞ of DSD and SD. This disparity suggested that gender differences might exist in the pharmacokinetic processes of DSD or SD in rats.

Safety and Toxicology of Magnolol and Honokiol.

Magnolia officinalis and Magnolia obovata bark extracts have been used for thousands of years in Chinese and Japanese traditional medicines and are still widely employed as herbal preparations for their sedative, antioxidant, anti-inflammatory, antibiotic, and antispastic effects. Neolignans, particularly magnolol and honokiol, are the main substances responsible for the beneficial properties of the magnolia bark extract (MBE). The content of magnolol and honokiol in MBE depends on different factors, including the Magnolia plant species, the area of origin, the part of the plant employed, and the method used to prepare the extract. The biological and pharmacological activities of magnolol and honokiol have been extensively investigated. Here we review the safety and toxicological properties of magnolol and honokiol as pure substances or as components of concentrated MBE, including the potential side-effects in humans after oral intake. In vitro and in vivo genotoxicity studies indicated that concentrated MBE has no mutagenic and genotoxic potential, while a subchronic study performed according to OECD (Organisation for Economic Co-operation and Development) guidelines established a no adverse effect level for concentrated MBE > 240 mg/kg b.w/d. Similar to other dietary polyphenols, magnolol and honokiol are subject to glucuronidation, and despite a relatively quick clearance, an interaction with pharmaceutical active principles or other herbal constituents cannot be excluded. However, intervention trials employing concentrated MBE for up to 1 y did not report adverse effects. In conclusion, over the recent years different food safety authorities evaluated magnolol and honokiol and considered them safe.

Application of a sensitive and specific LC-ESI-MS/MS method for the simultaneous quantification of twelve bioactive components in dog plasma for an intravenous pharmacokinetic study of Yiqifumai Injection in beagle dogs.

Yiqifumai Injection is a lyophilized powder preparation widely used to treat coronary heart disease. However, its in vivo bioactive components and pharmacokinetic behavior remain unknown. Therefore a sensitive and specific LC-MS/MS was developed and validated for the simultaneous quantification of eight saponins and four lignans in beagle dog plasma. The plasma samples were pretreated by protein precipitation with methanol-acetonitrile (1:1, v/v). Chromatographic separation of all the 12 analytes and estazolam (internal standard, IS) was successfully accomplished on an Ultimate® XB-C8 column (100 × 2.1 mm, 3 µm) with a gradient elution system. The total running time was 8 min with a flow rate of 0.40 mL/min. Acquisition of mass spectrometric data was performed via positive electrospray ionization in multiple reaction monitoring mode. The assay was fully validated in terms of selectivity, linear range, lower limit of quantitation, precision, accuracy, matrix effect, recovery and stability. This validated method was successfully applied to the pharmacokinetics of 12 bioactive components after intravenous administration of Yiqifumai Injection to beagle dogs at a dose of 0.541 g/kg.

Investigation of pharmacokinetics, tissue distribution and excretion of schisandrin B in rats by HPLC-MS/MS.

Schisandrin B has received much attention owing to its various biological activities. The present study was aimed at the formulation development of schisandrin B and investigation of the pharmacokinetic profiles, distribution and excretion of schisandrin B in Sprague-Dawley rats. In this study, micronized schisandrin B particles with particle size of 10-20 µm were chosen as the research object. Chromatographic separation was carried out on a BDS Hypersil C18 column (50 × 2.1 mm, i.d. 3.5 µm). Schisandrin B and deoxyschizandrin (internal standard) were detected without interference in the multiple reaction monitoring mode with positive electrospray ionization. The pharmacokinetic parameters were calculated by a noncompartmental method. The area under concentration-time curve and the maximum concentration showed a significant difference in gender. The calculated absolute oral bioavailability of schisandrin B was ~55.0% for female rat and 19.3% for male rat. Schisandrin B exhibited linear pharmacokinetics properties within the range of the tested oral dose (10, 20 and 40 mg/kg). After oral administration of schisandrin B, it was extensively distributed in ovary and adipose tissue. The result also showed very low urinary, biliary and fecal excretion of schisandrin B implying that schisandrin B was excreted mainly in the forms of metabolites.