Pharmacokinetic Profiling of Butylidenephthalide and Alisol B in Danggui-Shaoyao-San in Rats.

BACKGROUND AND OBJECTIVE: Danggui-Shaoyao-San (DSS), a famous Chinese formula, has been widely used to treat gynecological disorders since ancient times and has recently showed efficacy in treating Alzheimer's disease. Butylidenephthalide (BDPH) and alisol B (ALI) are recognized as the primary active ingredients of DSS. The objectives of the present study were to evaluate the pharmacokinetic comparative study of BDPH and ALI in herbal extracts and their purified forms. METHOD: A sensitive and specific high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) methodology was developed to determine the concentration level of BDPH and ALI in rat plasma. This approach enables a real-time pharmacokinetics profiling of BDPH and ALI in DSS extracts as well as their purified forms in rats after oral administration. RESULTS: The validated method showed an evident linearity over a wide range of dosages (r > 0.99) with sensitivity down to 1.0 ng/mL for each analyte. The extraction recovery of the analyte ranged from 80.8 to 99.1%. The pharmacokinetic parameters were significantly different in herbal extracts and their purified forms. The results showed that the absorption of both BDPH and ALI from DSS extracts was significantly greater compared with their purified forms. CONCLUSIONS: A highly specific, sensitive and rapid HPLC-MS/MS method was developed and applied for the determination of BDPH and ALI in rat plasma. It was found that BDPH and ALI had higher bioavailability in the DSS extract compared with their purified forms.

Pharmacokinetics and tissue distribution of five major triterpenoids after oral administration of Rhizoma Alismatis extract to rats using ultra high-performance liquid chromatography-tandem mass spectrometry.

Rhizoma Alismatis (RA) was wildly used for treatment of dysuria, pyelonephritis, hyperlipidemia, enteritis diarrhea, diabetes, inflammation, and cancer. Triterpenoids are the major active components of RA, and its extract is mainly composed of alisol A (ALA), alisol B (ALB), alisol C 23-acetate (ALC-23A), alisol A 24-acetate (ALA-24A), and alisol B 23-acetate (ALB-23A). In this study, a simple, reliable, and sensitive ultra high-performance liquid chromatography with triple quadrupole mass spectrometry (UHPLC-MS/MS) method was created and validated for the quantification of the five major triterpenoids in rat plasma and various tissues biosamples (including intestine, stomach, liver, kidney, fat, muscle, brain, heart, lung, spleen, and testes). The plasma and tissues biosamples were pretreated by direct precipitation deproteinization method with acetonitrile. 17α-Hydroxyprogesterone was used as internal standard (IS). The chromatography was performed on a Phenomenex C8 column (30×2.00mm, 1.8µm) at room temperature with gradient elution. Compounds were quantified by selected multi-reactions monitoring (SRM) scanning with positive electric spray ionization mode. The linearity of detection for each triterpene was respectively from 1 to 1000ng/mL for ALC-23A and ALA, from 4 to 4000ng/mL for ALA-24A, from 10 to 10,000ng/mL for ALB, and from 2 to 2000ng/mL for ALB-23B (r>0.99) with low quantification limits of 1-10ng/mL for all analytes. All of the other validation parameters were also in an acceptable range. The validated UHPLC-MS/MS method subsequently applied for the pharmacokinetic and tissue distribution studies of RA extract. After orally given 100mg/kg of RA extract, ALA was the most exposed component, followed by ALB and ALA-24A. Whereas significant gender difference was observed for ALB, ALA, and ALA-24A between female and male rats. The AUC(0-∞) of ALA, ALB, and ALA-24A in female rats were approximately 2-5 fold larger than that in male rats. These triterpenoids also displayed approximately 1.5-2 times longer half-life (t1/2) in female rats. Appearant Km, Vmax and Clint of ALA, ALB, and ALA-24A were calculated by substrate depletion approach, rat P450 CYP3A2 plays an important role in the metabolism of ALA, ALB, and ALA-24A, which is an important factor leading to the different exprosures of ALA, ALB, and ALA-24A between the male rats and the female rats. Furthermore, results from tissue distribution in male rats showed that the main tissue depots of five triterpenoids were the stomach/intestine, followed by the liver, brain, and fat. However, ALA was still measured in the kidney after a long elimination time. ALB and ALB-23B exhibited lower elimination rate in the testis. These results provide a fundamental support for further pharmacological development and clinical safety application of RA.

Synthesis of a fluorescent photoaffinity probe of OSW-1 by site-selective acylation of an inactive congener and biological evaluation.

A novel fluorescent photoaffinity probe of OSW-1 was prepared in two steps from a naturally occurring inactive congener by a sequential site-selective acylation strategy using Me2SnCl2. It displayed highly potent anticancer activity and a similar intracellular localization property to that of a fluorescently-tagged OSW-1, thereby demonstrating its potential utility in live cell studies.

Chronic administration of cholesterol oximes in mice increases transcription of cytoprotective genes and improves transcriptome alterations induced by alpha-synuclein overexpression in nigrostriatal dopaminergic neurons.

Cholesterol-oximes TRO19622 and TRO40303 target outer mitochondrial membrane proteins and have beneficial effects in preclinical models of neurodegenerative diseases leading to their advancement to clinical trials. Dopaminergic neurons degenerate in Parkinson's disease (PD) and are prone to oxidative stress and mitochondrial dysfunction. In order to provide insights into the neuroprotective potential of TRO19622 and TRO40303 for dopaminergic neurons in vivo, we assessed their effects on gene expression in laser captured nigrostriatal dopaminergic neurons of wildtype mice and of mice that over-express alpha-synuclein, a protein involved in both familial and sporadic forms of PD (Thy1-aSyn mice). Young mice were fed the drugs in food pellets or a control diet from 1 to 4months of age, approximately 10months before the appearance of striatal dopamine loss in this model. Unbiased weighted gene co-expression network analysis (WGCNA) of transcriptional changes revealed effects of cholesterol oximes on transcripts related to mitochondria, cytoprotection and anti-oxidant response in wild-type and transgenic mice, including increased transcription of stress defense (e.g. Prdx1, Prdx2, Glrx2, Hspa9, Pink1, Drp1, Trak1) and dopamine-related (Th, Ddc, Gch1, Dat, Vmat2, Drd2, Chnr6a) genes. Even at this young age transgenic mice showed alterations in transcripts implicated in mitochondrial function and oxidative stress (e.g. Bcl-2, Bax, Casp3, Nos2), and both drugs normalized about 20% of these alterations. Young Thy1-aSyn mice exhibit motor deficits that differ from parkinsonism and are established before the onset of treatment; these deficits were not improved by cholesterol oximes. However, high doses of TRO40303 improved olfaction and produced the same effects as dopamine agonists on a challenging beam test, specifically an increase in footslips, an observation congruent with its effects on transcripts involved in dopamine synthesis. High doses of TRO19622 increased alpha-synuclein aggregates in the substantia nigra; this effect, not seen with TRO40303 was inconsistent and may represent a protective mechanism as in other neurodegenerative diseases. Overall, the results suggest that cholesterol oximes, while not improving early effects of alpha-synuclein overexpression on motor behavior or pathology, may ameliorate the function and resilience of dopaminergic neurons in vivo and support further studies of neuroprotection in models with dopaminergic cell loss.

Fluorescent analog of OSW-1 and its cellular localization.

OSW-1 is a steroidal saponin, which has emerged as an attractive anticancer agent with highly cancer cell selective activity. A fluorescent analog was prepared from the natural product to analyze its cellular uptake and localization. We found that the fluorescent analog is rapidly internalized into cells and is primarily distributed in endoplasmic reticulum and Golgi apparatus.

[Research progress on pharmacology, pharmacokinetics and determination of ergosta-4,6,8 (14),22-tetraen-3-one].

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) is one of main components in many medicinal fungi. Ergone has been reported to possess the activities of diuresis, cytotoxicity, antitumor, immunosuppression, as well as treatment of chronic kidney disease. According to reported literatures, an overview of spectroscopy characteristics, content determination, pharmacological activity and pharmacokinetics, etc. for ergone is presented in this review. Furthermore, the present review can provide a certain reference value for the further study and development of ergone.

Enhanced distribution and anti-tumor activity of ergosta-4,6,8(14),22-tetraen-3-one by polyethylene glycol liposomalization.

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) was isolated from P. umbellatus, which has been demonstrated to possess a variety of pharmacological activities in vivo and in vitro. The purpose of this study was to evaluate the potent ergone formulations for cancer chemotherapy, the liposomal formulations were less toxic and provide longer systemic circulation time were selected as candidates of nanocarriers for ergone. The effect of modification polyethylene glycol (PEG) on the pharmacokinetics of liposome showed that the retaining time of ergone in blood circulation was prolonged by modified PEG. Moreover, the results of pharmacokinetic analysis showed that of PEG liposome was about 2.8 times higher than that of free PEG liposome after intravenous injection into normal rats due to the lower distribution into the reticuloendothelial system tissues. Since PEG liposome was able to stably encapsulate ergone in blood, area under plasma concentration-time curve of ergone was also extensively enhanced after intravenous dosing of ergone-PEG liposome into normal rats. In the in vivo studies utilizing solid tumor-bearing mice, it was confirmed that ergone-PEG liposome delivered remarkably larger amount of ergone to tumor tissue and provided more significant anti-tumor activity than free ergone. In conclusion, PEG liposome was an effective delivery formulation to achieve increased ergone release in tumor and therapeutic efficacy.

Folate-functionalized nanoparticles for controlled ergosta-4,6,8(14),22-tetraen-3-one delivery.

To improve the therapeutic effect of ergosta-4,6,8(14),22-tetraen-3-one (ergone), a folate-decorated ergone-bovine serum albumin nanoparticles (abbreviated FA-ergone-BSANPs) was prepared. The properties were extensively studied by Zetasizer Nano Particle Size Analyzer and TEM, which indicated the prepared nanoparticles were spherical in shape and uniform in size with a zeta potential of -23.8 mV. The drug-loading capacity also has been determined with drug loading content of 2.73% and encapsulation efficiency of 61.8%. In vitro release studies proved the much slow drug release from the nanoparticles during circulating in the blood stream and the increase of drug release at the target sites. The FA-ergone-BSANPs showed enhanced cellular uptake, increased targeting capacity, and increased cytotoxicity against KB cells over-expressing folate receptor (FR), which indicated that its potent cell-killing activity is specific for cells that express the FR. In vivo experiment also confirmed that FA-ergone-BSANPs represent a FR-targeted chemotherapeutic that can produce potent activity against FR-positive tumors. In conclusion, this report has a great significance in pharmacology and clinical medicine as well as methodology. Further detailed dose-optimization studies will be required for better understanding in vivo pharmacokinetic and bio-distribution behaviors.

Quantitative HPLC method and pharmacokinetic studies of ergosta-4,6,8(14),22-tetraen-3-one, a natural product with diuretic activity from Polyporus umbellatus.

A simple and specific HPLC method with dual wavelength UV detection for the determination of ergosta-4,6,8(14),22-tetraen-3-one (ergone) in rat plasma was developed and proved to be efficient. The method used ergosterol as internal standard (IS). Following a single-step protein precipitation, the analyte and IS were separated on an Inertsil ODS-3 column with a mobile phase containing methanol-water (99:1, v/v) at a flow rate of 1 mL/min. The analytes were detected by using UV detection at wavelength of 350 (ergone) and 283 (IS) nm, respectively. The calibration curve was linear over the range of 0.1-2.0 µg/mL and the lower limit of quantification was 0.1 µg/mL. The intra-day and inter-day precision studies showed good reproducibility with RSD less than 8.5%. The intra-day and inter-day accuracy ranged from 95.6 to 104%. Mean extraction recovery was above 95% at the low, medium and high concentrations. The present HPLC-UV method was simple and reliable. The method described herein had been successfully applied for the pharmacokinetic studies in male SD rats after administration of 20 mg/kg dose of solution of ergone.

Rapid resolution liquid chromatography-mass spectrometry and high-performance liquid chromatography-fluorescence detection for metabolism and pharmacokinetic studies of ergosta-4,6,8(14),22-tetraen-3-one.

Ergosta-4,6,8(14),22-tetraen-3-one (ergone) from many medicinal plants has been demonstrated to possess a variety of pharmacological activities in vivo and in vitro, including cytotoxic, diuretic and immunosuppressive activity. Metabolism and pharmacokinetic studies on rat were conducted for ergone. Rapid resolution liquid chromatography with atmospheric pressure chemical ionization tandem multi-stage mass spectrometry (RRLC-APCI-MS(n)) and high-performance liquid chromatography with fluorescence detection (HPLC-FLD) methods were applied for the identification and quantification of ergone and its metabolite from rat plasma, faeces and urine. A metabolite was identified by RRLC-DAD-APCI-MS(n): 22,23-epoxy-ergosta-4,6,8(14)-triaen-3-one (epoxyergone). The concentrations of the analyte with its metabolites were determined by HPLC-FLD at excitation wavelength of 370 nm and emission wavelength of 485 nm. The samples were deproteinized with methanol after addition of camptothecin as internal standard (IS). The analysis was performed on a Diamonsil C18 column (150 mm x 4.6 mm x 5 microm) with a mobile phase gradient consisting of methanol and water at a flow rate of 1 mL min(-1). The assay was linear over the concentration range of 42-1500, 36-7500 and 42-1500 ng mL(-1) for plasma, faecal homogenate and urine respectively. The absolute recoveries were found to be 97.0+/-1.2%, 98.1+/-0.7% and 96.6+/-1.8% for plasma, faecal homogenate and urine respectively. The intra-day and inter-day relative standard deviations (RSD) were less than 10%. The previous HPLC-MS/MS method is not affordable for most laboratories because of the specialty requirement and high equipment cost. However, the HPLC-FLD method is economic and operating simply for quantitative determination of ergone and its metabolite in rat plasma, faeces and urine. In addition, liquid chromatography coupled with ion trap multi-stage mass spectrometry is becoming a useful technique for ergone metabolite identification.

Possible hypocholesterolemic action of 15-ketosterol: replacement of dietary cholesterol absorption.

15-Ketosterol (5 alpha-cholest-8(14)-en-3 beta-ol-15-one), a potent inhibitor for sterol synthesis, has shown hypocholesterolemic effects in rodents, baboons, and rhesus monkeys. In recent studies we demonstrated that 15-ketosterol also exerted regulation on the input of cholesterol at the level of intestinal absorption. When Sprague Dawley rats were fed 0.05% 15-ketosterol in their chow for 10 days, a decrease in the absorption of cholesterol into lymph by 62 +/- 8% (n = 4) was observed in the first 48 hrs after the intragastic infusion of radiolabelled cholesterol. The absorption of cholesterol replaced by 15-ketosterol was further evidenced in the demonstration that the rats had a much more efficient rates of absorbing 15-ketosterol. Infusing rats with equal amount of the two sterols, the amount of 15-ketosterol absorbed was 3-4 fold that of cholesterol in the initial 10 hrs. 15-Ketosterol was absorbed in and mainly esterified with 18:1 packed into intestinal chylomicrons. Upon the intravenous injection of chylomicrons isolated from other animals receiving 3H-15-ketosterol intragastrically, the rapid appearance of radioactivity in the liver suggested that chylomicrons were taken up effectively. Ketosteryl ester was hydrolyzed back to 15-ketosterol in the liver. The metabolic fate of 15-ketosterol was very different from that of cholesterol. Over 85% of the administered dose was recovered in the bile 38 hrs after intravenous injection of 15-ketosterol. In contrast, only 15% of cholesterol and/or its metabolites was slowly secreted in the bile.(ABSTRACT TRUNCATED AT 250 WORDS)