akebia-saponin-d and hederagenin

This experiment's with aim was to study the pharmacokinetics of asperosaponin VI and its three metabolites (cauloside A, HN saponin F and hederagenin) via a sensitive high performance liquid chromatography connected with electrospray ionization triple quadrupole mass spectrum (HPLC-ESI-MS/MS). Chromatographic separation was achieved on a reverse phase C18 column with a gradient mobile phase of CH3CN-water with 0.1 % HCOOH at a flow rate of 0.3 mL/min. Sample analysis was simultaneously performed with a multiple reaction monitoring mode using target determination ions at m/z 927.5 → 603.4 for asperosaponin VI, m/z 811.1 → 603.4 for cauloside A, m/z 649.4 → 603.4 for HN saponin F, m/z 71.4 → 393.3 for hederagenin and m/z 307.0 → 161.1 for warfarin as the internal standard. The calibration curve was linear at the range of 0.25-500 ng/mL, and the lower limit of quantification was 0.25 ng/mL for each compound. While the precisely intra-assay and inter-assay variabilities were <9.5 and 7.8 %, respectively; accuracy was determined at the concentrations of 5, 25, 100 ng/mL for all the analytes with the relative standard deviation (%) no more than 15.0 %. Consequently, the validated method could be successfully and precisely applied to the pharmacokinetic study of asperosaponin VI and its metabolites. As a result, the pharmacokinetic parameters of cauloside A, HN saponin F and hederagenin such as T max were obtained at 9.33 ± 2.49, 7.33 ± 0.47 and 12.33 ± 2.36 h, respectively.

Topics: Animals; Chromatography, High Pressure Liquid; Male; Oleanolic Acid; Rats; Rats, Sprague-Dawley; Saponins; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

Two high-performance liquid chromatography (HPLC) coupled with electrospray ionization (ESI) mass spectrometry methods were developed and validated for the simultaneous determination of asperosaponin VI (A-VI) and hederagenin (HG) in rats' various tissues. Biological samples were processed with methanol extraction, and glycyrrhetinic acid was chosen as the internal standard (IS). The analytes were separated on a C18 column with two gradient elution programs for different rat tissue samples. The MS/MS detection was carried out by monitoring the transitions of m/z [MH](-) 927.5→603.4 for A-VI, m/z [MH](-) 471.3→471.3 for HG and m/z [MH](-) 469.4→425.4 for the IS, respectively. The lower limits of quantification (LLOQ) for the two analytes in different rat tissues were 2-6ng/mL, respectively. The methods were successfully applied to a tissue distribution study of A-VI and its active metabolite HG in rats. The results of the tissue distribution study showed that the highest concentration of A-VI was in the gastrointestinal (GI) tract. Besides, A-VI was mainly distributed in lung, liver, fat and ovary. HG was almost undetectable in most tissues except for the GI tract.

Topics: Animals; Chromatography, High Pressure Liquid; Dipsacaceae; Drugs, Chinese Herbal; Female; Liver; Lung; Male; Oleanolic Acid; Ovary; Rats; Rats, Sprague-Dawley; Saponins; Tandem Mass Spectrometry; Tissue Distribution

A rapid and sensitive ultra-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-TQ/MS) method was developed for simultaneous quantification of Akebia saponin D (ASD) and its five metabolites in intestinal mixtures of bacteria from human feces. After protein precipitation, the analytes and internal standard (IS), glycyrrhetinic acid, were determined in selected ion recording (SIR) mode with negative ion ESI source. Chromatographic separation was carried out on an ACQUITY UPLC™ BEH C18 column (100mm×2.1mm, 1.7μm) using gradient elution. The mobile phase consisted of solvents A (acetonitrile) and B (0.1% aqueous formic acid) at the flow rate of 0.4mL/min. Each sample was chromatographed within 10.5min including equilibration time. The linearity ranged from 0.1 to 100μg/mL for ASD, and 2-1000ng/mL for five metabolites, Dipsacus saponin A (M1), HN-saponin F (M2), hederagenin-28-O-β-d-glucopyranoside (M3), Akebia saponin PA (M4), hederagenin (M5). The limits of detection (LOD) were 0.41, 0.59, 0.61, 0.55, 0.52 and 0.31ng/mL for ASD, M1, M2, M3, M4 and M5, respectively. The intra- and inter-day precision was all within 11.1% and accuracy ranged from -8.33% to 12.47%. The conversion rate of five metabolites was 41.21% in 24h. The method was validated and successfully applied to quantification of ASD and its five metabolites in human intestinal bacteria.

Topics: Bacteria; Chromatography, High Pressure Liquid; Feces; Humans; Intestines; Mass Spectrometry; Oleanolic Acid; Reproducibility of Results; Saponins; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method operated in the positive/negative electrospray ionization (ESI) switching mode has been developed and validated for the simultaneous determination of asperosaponin VI and its active metabolite hederagenin in rat plasma. After addition of internal standards diazepam (for asperosaponin VI) and glycyrrhetic acid (for hederagenin), the plasma sample was deproteinized with acetonitrile, and separated on a reversed phase C18 column with a mobile phase of methanol (solvent A)-0.05% glacial acetic acid containing 10 mM ammonium acetate and 30 μM sodium acetate (solvent B) using gradient elution. The detection of target compounds was done in multiple reaction monitoring (MRM) mode using a tandem mass spectrometry equipped with positive/negative ion-switching ESI source. At the first segment, the MRM detection was operated in the positive ESI mode using the transitions of m/z 951.5 ([M+Na](+))→347.1 for asperosaponin VI and m/z 285.1 ([M+H](+))→193.1 for diazepam for 4 min, then switched to the negative ESI mode using the transitions of m/z 471.3 ([M-H](-))→471.3 for hederagenin and m/z 469.4 ([M-H](-))→425.4 for glycyrrhetic acid, respectively. The sodiated molecular ion [M+Na](+) at m/z 951.5 was selected as the precursor ion for asperosaponin VI, since it provided better sensitivity compared to the deprotonated and protonated molecular ions. Sodium acetate was added to the mobile phase to make sure that abundant amount of the sodiated molecular ion of asperosaponin VI could be produced, and more stable and intensive mass response of the product ion could be obtained. For the detection of hederagenin, since all of the mass responses of the fragment ions were very weak, the deprotonated molecular ion [M-H](-)m/z 471.3 was employed as both the precursor ion and the product ion. But the collision energy was still used for the MRM, in order to eliminate the influences induced by the interference substances from the rat plasma. The validated method was successfully applied to study the pharmacokinetics of asperosaponin VI and its active metabolite hederagenin in rat plasma after oral administration of asperosaponin VI at a dose of 90 mg/kg.

Topics: Administration, Oral; Animals; Chromatography, Liquid; Drug Stability; Oleanolic Acid; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Saponins; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

According to Traditional Chinese Medicine, Alzheimer's disease (AD) is regarded as senile dementia, and the etiopathogenesis lies in kidney deficiency during aging. Dipsacus asper Wall (DAW), a well-known traditional Chinese medicine for enhancing kidney activity, may possess the therapeutic effects against AD. Our objectives were to investigate the protective effects of DAW against the amyloid-beta peptide (A beta)-induced cytotoxicity and explore its major active components. Injury of PC 12 cells mediated by A beta(25-35) was adopted to assess the cytoprotective effects of DAW aqueous extract and various fractions. Salvianolic acid B, a polyphenol compound isolated from Salvia miltiorrhiza, was employed as a positive control agent due to its markedly protective effect against neurotoxicity of amyloid beta. Five chemical fractions (i.e. alkaloids, essential oil, saponins, iridoid glucoside and polysaccharides) were prepared for activity test and analyzed by HPLC for active components identification. In addition, Akebia saponin D (the most important compound in DAW saponins) and hederagenin (the mother nucleus of akebia saponin D) were prepared for testing of their activity. DAW water extract, saponins fraction and akebia saponin D had the neuroprotective capacity to antagonize A beta(25-35)-induced cytotoxicity in PC 12 cells. In contrast, other fractions and hederagenin had no cytoprotective action. This research suggests that DAW may represent a potential treatment strategy for AD and akebia saponin D is one of its active components.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Calcium; Cell Survival; Cytoprotection; Dipsacaceae; Drugs, Chinese Herbal; L-Lactate Dehydrogenase; Oleanolic Acid; PC12 Cells; Rats; Saponins