Screening and verification of CYP3A4 inhibitors from Bushen-Yizhi formula to enhance the bioavailability of osthole in rat plasma.

ETHNOPHARMACOLOGICAL RELEVANCE: With the features of multiple-components and targets as well as multifunction, traditional Chinese medicine (TCM) has been widely used in the prevention and treatment of various diseases for a long time. During the application of TCM, the researches about bioavailability enhancement of the bioactive constituents in formula are flourishing. Bushen-Yizhi formula (BSYZ), a TCM prescription with osthole (OST) as one of the main bioactive ingredients, have been widely used to treat kidney deficiency, mental retardation and Alzheimer's disease. However, the underlying biological mechanism and compound-enzyme interaction mediated bioavailability enhancement of OST are still not clearly illuminated. AIM OF THE STUDY: The aim of this study is to explore the material basis and molecular mechanism from BSYZ in the bioavailability enhancement of OST. Screening the potential CYP3A4 inhibitors using theoretical prediction and then verifying them in vitro, and pharmacokinetics study of OST in rat plasma under co-administrated of screened CYP3A4 inhibitors and BSYZ were also scarcely reported. MATERIALS AND METHODS: Screening of CYP3A4 inhibitors from BSYZ was performed with molecular docking simulation from systems pharmacology database. The screened compounds were verified by using P450-Glo Screening Systems. A multiple reaction monitoring (MRM) mass spectrometry method was established for OST quantification. Male Sprague-Dawley rats divided into four groups and six rats in each group were employed in the pharmacokinetics study of OST. The administrated conditions were group I, OST (20 mg/kg); group II, BSYZ (containing OST 1 mg/mL, at the dose of 20 mg/kg OST in BSYZ); group III, co-administration of ketoconazole (Ket, 75 mg/kg) and OST (20 mg/kg); group IV, co-administration of CYP3A4 inhibitor (10 mg/kg) and OST (20 mg/kg). They were determined by using HPLC-MS/MS (MRM) and statistical analysis was performed using student's t-test with p < 0.05 as the level of significance. RESULTS: 21 potential CYP3A4 inhibitors were screened from BSYZ compounds library. From the results of verification in vitro, we found 4 compounds with better CYP3A4 inhibition efficiency including Oleic acid, 1,2,3,4,6-O-Pentagalloylglucose, Rutin, and Schisantherin B. Under further verification, Schisantherin B exhibited the best inhibitory effect on CYP3A4 (IC50 = 0.339 µM), and even better than the clinically used drug (Ket) at the concentration of 5 µM. In the study of pharmacokinetics, the area under the curve (AUC, ng/L*h) of OST after oral administration of BSYZ, Ket and Schisantherin B (2196.23 ± 581.33, 462.90 ± 92.30 and 1053.03 ± 263.62, respectively) were significantly higher than that of pure OST treatment (227.89 ± 107.90, p < 0.01). CONCLUSIONS: Schisantherin B, a profoundly effective CYP3A4 inhibitor screened from BSYZ antagonized the metabolism of CYP3A4 on OST via activity inhibition, therefore significantly enhanced the bioavailability of OST in rat plasma. The results of this study will be helpful to explain the rationality of the compatibility in TCM formula, and also to develop new TCM formula with more reasonable drug compatibility.

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.

SB431542-Loaded Liposomes Alleviate Liver Fibrosis by Suppressing TGF-ß Signaling.

Liver fibrosis is a common outcome of most chronic liver diseases, but there is no clinically approved drug for its treatment. Previous studies have reported the potential of SB431542 as an inhibitor of TGF-ß signaling in the treatment of liver fibrosis, but it shows poor water solubility and low bioavailability. Here, we improve these characteristics of SB431542 by loading it into liposomes (SB-Lips) with two FDA-approved excipients: soya phosphatidyl S100 and Solutol HS15. In vitro, SB-Lips had stronger inhibitory effects on the proliferation and activation of hepatic stellate cells LX-2 than free SB. After an intravenous injection in a CCl4-induced liver fibrosis mouse model, SB-Lips accumulated preferentially in the liver, its area under the concentration-time curve was significantly higher than that of free SB431542, and it alleviated hepatic fibrosis significantly more than free drug, which was associated with greater inhibition of TGF-ß signaling. Furthermore, SB-Lips did not cause significant injury to other organs. These results suggest that our liposomal system is safe and effective for delivering SB431542 to fibrotic liver.

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.

Lipid Profiling Reveals Browning Heterogeneity of White Adipose Tissue by Β3-Adrenergic Stimulation.

BACKGROUND: White adipose tissue (WAT) browning confers beneficial effects on metabolic diseases. However, visceral adipose tissue (VAT) is not as susceptible to browning as subcutaneous adipose tissue (SAT). AIM: Interpreting the heterogeneity of VAT and SAT in brown remodeling and provide promising lipid targets to promote WAT browning. METHODS: We first investigated the effects of ß3-adrenergic stimulation by CL316,243 on systemic metabolism. Then, high-coverage targeted lipidomics approach with multiple reaction monitoring (MRM) was utilized to provide extensive detection of lipid metabolites in VAT and SAT. RESULTS: CL316,243 notably ameliorated the systemic metabolism and induced brown remodeling of SAT but browning resistance of VAT. Comprehensive lipidomics analysis revealed browning heterogeneity of VAT and SAT with more dramatic alteration of lipid classes and species in VAT rather than SAT, though VAT is resistant to browning. Adrenergic stimulation differentially affected glycerides content in VAT and SAT and boosted the abundance of more glycerophospholipids species in VAT than in SAT. Besides, CL316,243 increased sphingolipids in VAT without changes in SAT, meanwhile, elevated cardiolipin species more prominently in VAT than in SAT. CONCLUSIONS: We demonstrated the browning heterogeneity of WAT and identified potential lipid biomarkers which may provide lipid targets for overcoming VAT browning resistance.

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.

DS86760016, a Leucyl-tRNA Synthetase Inhibitor with Activity against Pseudomonas aeruginosa.

DS86760016 is a new leucyl-tRNA-synthetase inhibitor at the preclinical development stage. DS86760016 showed potent activity against extended-spectrum multidrug-resistant Pseudomonas aeruginosa isolated from clinical samples and in vitro biofilms. In a murine catheter-associated urinary tract infection model, DS86760016 treatment resulted in significant eradication of P. aeruginosa from the kidney, bladder, and catheter without developing drug resistance. Our data suggest that DS86760016 has the potential to act as a new drug for the treatment of Pseudomonas infections.

Simultaneous quantification of Schisandrin B enantiomers in rat plasma by chiral LC-MS/MS: Application in a stereoselective pharmacokinetic study.

Schisandrin B (Sch B) has received much attention owing to its various biological activities. Schisandrin B exists as a racemate in "wuweizi", a traditional Chinese medicine in China. In the present study, a novel chiral LC-MS/MS method was developed for enantioselective separation and determination of Schisandrin B in rat plasma. The plasma samples were prepared by liquid-liquid extraction (LLE). Schisandrol B was used as internal standard. Chiral separation was obtained on a Chiralpak IC column using 0.1% (v/v) formic acid in mixture of methanol and water (90:10, v/v) as a mobile phase. Parameters including the selectivity, linearity, precision, accuracy, extraction recovery, matrix effect and stability were evaluated. The method described here is simple and reproducible. The lower limit of quantification of 5.0 ng/mL for each Sch B enantiomer permits the use of the method in investigating the stereoselective pharmacokinetics of Sch B. Following racemic Sch B and "wuweizi" extracts, the area under the curve of (8R, 8'S)-Sch B was statistically higher than the one of (8S, 8' R)-Sch B, with a ratio of 1.16-1.40 in three cases. This study firstly reports the development and validation of enantioselective behavior of Sch B in vivo, and provides a reference for clinical practice and encourages further research into Sch B enantioselective metabolism and drug interactions.

Establishment and validation of microsampling techniques in wild rodents for ecotoxicological research.

Compounds and products in the biocide and plant protection sector can only be registered after formal risk assessment to ensure safety for users and the environment. In bird and mammal risk assessment, this is routinely done using generic focal species as models, which are of particular exposure risk. Such a species is the common vole (Microtus arvalis) due to its high food intake relative to the low body weight. For wild species, biological samples, data and hence realistic exposure estimations are particularly difficult to obtain. In recent years, advances have been made in the techniques related to serial microsampling of laboratory mice and rats that allow for a reduction in sampling volumes. Similar progress in wild species sampling is missing. This study presents a proof of concept to dose wild rodents with relevant compounds and to draw serial, low volume blood samples suitable for state-of-the art toxicokinetic analyses. For the first time, the jugular vein of common voles was used to administer compounds (two frequently used fungicidal components). This procedure and the following microsampling of blood (2 × 10 µl six times within 24 hours) from the lateral tail vein did not affect body weight and mortality of voles. Samples were sufficient to detect dissipation patterns of the compounds from blood in toxicokinetic analysis. These results suggest that microsampling can be well translated from laboratory mice to wild rodent species and help to obtain realistic exposure estimates in wild rodents for ecotoxicological studies as well as to promote the 3R concept in studies with wild rodent species.

Prediction of Drug-Drug Interaction between Tacrolimus and Principal Ingredients of Wuzhi Capsule in Chinese Healthy Volunteers Using Physiologically-Based Pharmacokinetic Modelling.

Schisantherin A and schisandrin A, the most abundant active ingredients of Wuzhi capsule, are known to inhibit tacrolimus metabolism by inhibiting CYP3A4/5. We aimed to predict the contribution of schisantherin A and schisandrin A to drug-drug interaction (DDI) between Wuzhi capsule and tacrolimus using physiologically-based pharmacokinetic (PBPK) modelling. Firstly, the inhibition mechanism of schisantherin A and schisandrin A on CYP3A4/5 was investigated. Thereafter, PBPK models of schisantherin A, schisandrin A and tacrolimus were established. Finally, tacrolimus pharmacokinetics were evaluated after the combined use with schisantherin A or schisandrin A. The blood area under the curve (AUC) of tacrolimus increased 1.77- and 2.61-fold after a single dose and multiple doses of schisantherin A, respectively. Meanwhile, schisandrin A inhibited tacrolimus metabolism to a smaller extent. Also, it showed that mechanism-based inhibition (MBI) played a more important role in DDI than reversible inhibition after long-term administration, while reversible inhibition was comparable to MBI after single-dose administration. In conclusion, we utilized PBPK modelling to quantify the contribution of schisantherin A and schisandrin A to DDI between tacrolimus and Wuzhi capsule. This may provide more insights for the rational use of this drug combination.

Potentiation of excitatory synaptic transmission ameliorates aggression in mice with Stxbp1 haploinsufficiency.

Genetic studies point to a major role of de novo mutations in neurodevelopmental disorders of intellectual disability, autism spectrum disorders, and epileptic encephalopathy. The STXBP1 gene encodes the syntaxin-binding protein 1 (Munc18-1) that critically controls synaptic vesicle exocytosis and synaptic transmission. This gene harbors a high frequency of de novo mutations, which may play roles in these neurodevelopmental disorders. However, the system and behavioral-level pathophysiological changes caused by these genetic defects remain poorly understood. Constitutional (Stxbp1+/-), dorsal-telencephalic excitatory (Stxbp1fl/+/Emx), or global inhibitory neuron-specific (Stxbp1fl/+/Vgat) mice were subjected to a behavioral test battery examining locomotor activity, anxiety, fear learning, and social interactions including aggression. Furthermore, measurements of local field potentials in multiple regions of the brain were performed. Stxbp1+/- male mice exhibited enhanced aggressiveness and impaired fear learning associated with elevated gamma activity in several regions of the brain including the prefrontal cortex. Stxbp1fl/+/Emx mice showed fear-learning deficits, but neither Stxbp1fl/+/Emx nor Stxbp1fl/+/Vgat mice showed increased aggressiveness. Pharmacological potentiation of the excitatory transmission at active synapses via the systemic administration of ampakine CX516, which enhances the excitatory postsynaptic function, ameliorated the aggressive phenotype of Stxbp1+/- mice. These findings suggest that synaptic impairments of the dorsal telencephalic and subcortical excitatory neurons cause learning deficits and enhanced aggression in Stxbp1+/- mice, respectively. Additionally, normalizing the excitatory synaptic transmission is a potential therapeutic option for managing aggressiveness in patients with STXBP1 mutations.

Towards quantification of toxicity of lithium ion battery electrolytes - development and validation of a liquid-liquid extraction GC-MS method for the determination of organic carbonates in cell culture materials.

A novel method based on liquid-liquid extraction with subsequent gas chromatography separation and mass spectrometric detection (GC-MS) for the quantification of organic carbonates in cell culture materials is presented. Method parameters including the choice of extraction solvent, of extraction method and of extraction time were optimised and the method was validated. The setup allowed for determination within a linear range of more than two orders of magnitude. The limits of detection (LODs) were between 0.0002 and 0.002 mmol/L and the repeatability precisions were in the range of 1.5-12.9%. It could be shown that no matrix effects were present and recovery rates between 98 and 104% were achieved. The methodology was applied to cell culture models incubated with commercial lithium ion battery (LIB) electrolytes to gain more insight into the potential toxic effects of these compounds. The stability of the organic carbonates in cell culture medium after incubation was studied. In a porcine model of the blood-cerebrospinal fluid (CSF) barrier, it could be shown that a transfer of organic carbonates into the brain facing compartment took place. Graphical abstract Schematic setup for the investigation of toxicity of lithium ion battery electrolytes.

Time- and NADPH-Dependent Inhibition on CYP3A by Gomisin A and the Pharmacokinetic Interactions between Gomisin A and Cyclophosphamide in Rats.

The traditional Chinese medicine Schisandra chinensis has remarkable protective effects against chemical-induced toxicity. Cyclophosphamide (CTX), in spite advances in chemotherapy and immunosuppressive regimes, is prone to cause severe toxicity due to its chloroacetaldehyde (CAA) metabolite produced by CYP3A. Our previous study identified that S. chinensis extract (SCE) co-administration potently decreased CAA production and attenuated liver, kidney and brain injuries in CTX-treated rats. Gomisin A (Gom A) is proved to be one of the most abundant bioactive lignans in S. chinensis with a significant CYP3A inhibitory effect. To find out whether and how Gom A participated in the chemoprevention of SCE against CTX toxicity, the Gom A-caused CYP3A inhibition in vitro as well as the pharmacokinetic interactions between Gom A and CTX in vivo were examined in this study. Using human liver microsomes, a reversible inhibition assay revealed that Gom A was a competitive inhibitor with a KI value of 1.10 µM, and the time- and NADPH-dependent CYP3A inhibition of Gom A was observed in a time-dependent inhibition assay (KI = 0.35 µM, kinact = 1.96 min-1). Hepatic CYP3A mRNA expression experienced a significant increase in our rat model with Gom A administration. This explained why CAA production decreased in the 0.5 h- and 6 h-pretreatment rat groups while it increased in the 24 h- and 72 h-pretreatment groups, indicating a bidirectional effect of Gom A on CYP3A-mediated CTX metabolism. The present study suggested that Gom A participates like SCE in the pharmacokinetic intervention of CTX by blocking CYP3A-mediated metabolism and reducing CAA production, and thus plays an important role in the chemopreventive activity of S. chinensis against CTX toxicity, in addition to the previously recognized protective effects. Also, the combined use of S. chinensis preparation or other drugs containing Gom A as the main component with CTX needed to be addressed for better clinical intervention.

Absorption, distribution, metabolism, and excretion of [14 C]sesamin in rats.

SCOPE: Sesamin is a major lignan in sesame seeds and has various physiological effects. Although metabolism of sesamin by cytochrome P450 or intestinal microflora has been reported, little is known concerning the mass balance, pharmacokinetics, and tissue distribution of sesamin. METHODS AND RESULTS: Absorption, distribution, metabolism, and excretion of [14 C]sesamin were investigated after a single oral dose of 5 mg/kg in rats. Sesamin was absorbed with peak plasma radioactivity at 1.0 h and declined with a terminal half-life 4.7 h. The cumulative excretion of radioactivity was 37.5 ± 3.1% in urine and 58.7 ± 4.8% in feces. In bile duct-cannulated rats, the cumulative excretion of radioactivity was 66.3 ± 8.4% in bile and 27.8 ± 10.2% in urine. Tissue distribution was investigated using quantitative whole-body autoradiography. Radioactivity was widely distributed over the whole body and was highly detected in the liver and kidney. The metabolites profile was examined using radiochromatography. Sesamin was mainly distributed in the form of conjugate metabolites. CONCLUSIONS: Sesamin was absorbed efficiently and distributed over the whole body. In particular, sesamin was highly distributed in the form of the metabolites in the liver and kidney. The results of this study are useful in elucidating the action mechanism of sesamin.

Bioanalytical assay development and validation for simultaneous quantification of five schisandra lignans in rat primary hepatocytes based on LC-MS/MS: application to a real-time uptake study for Schisandra Lignan Extract.

Schisandra lignans, mainly including schizandrol A, schizandrol B, schisantherin A, schizandrin A, schizandrin B, etc., are the major active ingredients of Schisandra chinensis. In the present study, a robust liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for the simultaneous quantification of schisandra lignans in rat primary hepatocytes. Lovastatin was used as an internal standard, and chromatographic separation was achieved on a Shimadzu C18 column with a gradient elution at the flow rate of 0.2 mL/min. All of the analytes were detected in multiple reaction monitoring mode with positive electrospray ionization since the sodium adduct ion [M + Na]+ was observed as the most intensive peak in the MS spectrum. For schizandrol A, schisantherin A and schizandrin A, the dynamic range was within 2-1000 ng/mg protein, and the linear range of schizandrol B and schizandrin B was from 5 to 1000 ng/mg protein. The intra- and inter-day precision was <15% and the accuracy (relative error) ranged from -15 to 15%. No significant variation was observed in the stability tests. The validated method was then successfully applied to the time-dependent uptake study for the Schisandra Lignan Extract in rat primary hepatocytes.

Trabectedin for the treatment of soft tissue sarcomas.

INTRODUCTION: Trabectedin, a marine-derived DNA-binding antineoplastic agent, has been registered by the EMA and recently also by the FDA for the treatment of patients with advanced soft-tissue sarcoma (STS), a rare and heterogeneous disease. AREAS COVERED: The antitumor activity of trabectedin is related both to direct effects on cancer cells, such as growth inhibition, cell death and differentiation, and indirect effects related to its anti-inflammatory and anti-angiogenic properties. Furthermore, trabectedin is the first compound that targets an oncogenic transcription factor with high selectivity in mixoid liposarcomas. This peculiar mechanism of action is the basis of its clinical development. The clinical pharmacology of trabectedin, the subsequent phase I, II and III trials are summarized and put into perspectives in this review. EXPERT OPINION: Trabectedin is a relevant pleiotropic antitumoral agent within the complex scenario of the management of STS. It can be used in advanced STS, either after failure of anthracyclines and ifosfamide or in patients unfit for these drugs, especially when reaching a high-tumor control and a long-term benefit is a priority. Toxicity profile is acceptable and manageable with no reported cumulative toxicities. Therefore, trabectedin has become one relevant therapeutic option in metastatic STS, especially in selected histologies.

Comparative pharmacokinetics and tissue distribution profiles of lignan components in normal and hepatic fibrosis rats after oral administration of Fuzheng Huayu recipe.

ETHNOPHARMACOLOGICAL RELEVANCE: Fuzheng Huayu recipe (FZHY) is formulated on the basis of Chinese medicine theory in treating liver fibrosis. AIM OF THE STUDY: To illuminate the influence of the pathological state of liver fibrosis on the pharmacokinetics and tissue distribution profiles of lignan components from FZHY. MATERIALS AND METHODS: Male Wistar rats were randomly divided into normal group and Hepatic fibrosis group (induced by dimethylnitrosamine). Six lignan components were detected and quantified by ultrahigh performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in the plasma and tissue of normal and hepatic fibrosis rats. RESULTS: A rapid, sensitive and convenient UHPLC-MS/MS method has been developed for the simultaneous determination of six lignan components in different rat biological samples successfully. After oral administration of FZHY at a dose of 15g/kg, the pharmacokinetic behaviors of schizandrin A (SIA), schizandrin B (SIB), schizandrin C (SIC), schisandrol A (SOA), Schisandrol B (SOB) and schisantherin A (STA) have been significantly changed in hepatic fibrosis rats compared with the normal rats, and their AUC(0-t) values were increased by 235.09%, 388.44%, 223.30%, 669.30%, 295.08% and 267.63% orderly (P<0.05). Tissue distribution results showed the amount of SIA, SIB, SOA and SOB were significant increased in heart, lung, spleen and kidney of hepatic fibrosis rats compared with normal rats at most of the time point (P<0.05). Meanwhile, the result also reveals that the hepatic fibrosis could delay the peak time of lignans in liver. CONCLUSION: The results proved that the established UHPLC-MS/MS method could be applied to the comparative study on pharmacokinetics and tissue distribution of lignan components in normal and hepatic fibrosis rats. The hepatic fibrosis could alter the pharmacokinetics and tissue distribution properties of lignan components in rats after administration of FZHY. The results might be helpful for guide the clinical application of this medicine.

Phase I study of the safety and pharmacokinetics of trabectedin with docetaxel in patients with advanced malignancies.

PURPOSE: Combination therapy with trabectedin and docetaxel was evaluated in patients with advanced malignancies. METHODS: In this open-label phase 1 study, docetaxel (60 or 75 mg/m(2); 1-h intravenous infusion) was given on day 1 of a 21-day cycle in combination with escalating doses of trabectedin (0.4-1.3 mg/m(2) by 3-h intravenous infusion, 1 h after docetaxel) and prophylactic granulocyte colony-stimulating factor (G-CSF). Maximum tolerated dose (MTD) as primary objective and safety, plasma pharmacokinetics, and antitumor activity as secondary objectives were assessed. RESULTS: Patients (N = 49) received a median of four cycles of treatment. MTD was 1.3 mg/m(2) trabectedin and 60 mg/m(2) docetaxel for patients with limited and 1.1 mg/m(2) trabectedin and 60 mg/m(2) docetaxel for patients with unlimited prior chemotherapy. Dose-limiting toxicities (during cycle 1) included elevated alanine aminotransferase (ALT) and fatigue in patients with limited prior chemotherapy and elevated ALT and febrile neutropenia in those with unlimited prior chemotherapy. The most common drug-related adverse events were nausea (65 %), fatigue (63 %), and neutropenia (53 %). One patient achieved a complete response. Thirty patients had stable disease, and 11 had stable disease for ≥6 months. Pharmacokinetic results for trabectedin plus docetaxel were similar to those previously reported for the single agents. CONCLUSION: In patients with previously treated, advanced malignancies, the combination of therapeutic doses of trabectedin and docetaxel showed clinical activity and was tolerable with prophylactic G-CSF, with no evidence of clinically important drug interactions.

Pharmacokinetics, tissue distribution, and tentative metabolite identification of sauchinone in mice by microsampling and HPLC-MS/MS methods.

Sauchinone, a biologically active lignan found in Saururus chinensis (Saururaceae), exerts various biological activities against jaundice, inflammatory disease, hepatic steatosis, and oxidative injury. Despite its diverse applications, there exists some information about sauchinone's pharmacokinetics but its tissue distribution, metabolism, and tentative metabolites have not been reported yet. Thus we investigated the pharmacokinetics of sauchinone in mice using microsampling and HPLC-MS/MS methods. Sauchinone presented linear pharmacokinetics at intravenous doses 7.5-20 mg/kg and oral doses 20-500 mg/kg. However, the metabolism of sauchinone was saturated and this agent presented nonlinear pharmacokinetics at 50 mg/kg in the intravenous study. At sauchinone 20 mg/kg the F of sauchinone was 7.76% of the oral dose despite that 77.9% of sauchinone was absorbed. This might be due to extensive metabolism of sauchinone in S9 fractions of liver and small intestine. Tentative metabolites of sauchinone by oxidation, dioxidation, methylation, demethylation, dehydrogenation, or bis-glucuronide conjugation were detected in plasma and S9 fractions of liver, intestine, and kidney. The distribution of sauchinone was considerably high (tissue-to-plasma (T/P) ratios, >1) in liver, small intestine, kidney, lung, muscle, fat, or mesentery after intravenous and oral administration and in stomach and large intestine only after oral administration. The protein binding value of sauchinone was 53.0%. These pharmacokinetic data of sauchinone provide an important basis for preclinical applications and experimental methods can be adjusted to evaluate the pharmacokinetics of natural products in mice.