[Determination of seven ingredients of different grades Alismatis Rhizoma by QAMS method].

The present study is to establish a quantitative analysis of multi-components by single marker(QAMS) for determining contents of seven compositions in Alismatis Rhizoma, alismoxide, alisol C 23-acetate, alisol A, alismol, alisol B, alisol B 23-acetate and 11-deoxy-alisol B. Six relative correction factors(RCFs) of alismoxide, alisol C 23-acetate, alisol A, alismol, alisol B and 11-deoxy-alisol B were established in the UPLC method with alisol B 23-acetate as the internal standard, which was to calculate the mass fraction of each. The mass fraction of seven effective constituents in Alismatis Rhizoma was calculated by the external standard method(ESM) at the same time. Compared with the content results determined by the ESM and QAMS, the feasibility and accuracy of QAMS method were verified. Within the linear range, the RCFs of alismoxide, alisol C 23-acetate, alisol A, alismol, alisol B, 11-deoxy-alisol B were 0.946, 4.183, 0.915, 1.039, 0.923 and 1.244, respectively, with good repeatability in different experimental conditions. There was no significant difference between the QAMS method and ESM method. Then, QAMS method was applied to determination of the different degree Alismatis Rhizoma from different areas. As a result, the concentrations of 7 components have differences in different areas, but no significant differences in different grades. The QAMS method is feasible and accurate for the determination of the seven chemical compositions, and which can be used for quality control of Alismatis Rhizoma.

Diuretic Activity of Compatible Triterpene Components of Alismatis rhizoma.

Alismatis rhizoma (AR), the dried rhizoma of Alisma orientale Juzepzuk (Alismataceae), is a traditional Chinese medicine. AR is an important part of many prescriptions and is commonly used as a diuretic agent in Asia. This study aimed to evaluate the diuretic effects of total triterpene extract (TTE) and triterpene component compatibility (TCC, the mixture of alisol B 23-acetate, alisol B, alisol A 24-acetate, alisol A, and alisol C 23-acetate) of AR in saline-loaded rats. The optimal diuretic TCC of AR was optimized using a uniform design. Different doses (5, 20, and 40 mg/kg) of TTE and TCC groups (N1-N8) were orally administered to rats. Urinary excretion rate, pH, and electrolyte excretion were measured in the urine of saline-loaded rats. Results showed that TTE doses increased urine volume and electrolyte excretion compared with the control group. All uniformly designed groups of TCC also increased urine excretion. In addition, optimal diuretic TCC was calculated (alisol B 23-acetate: alisol B: alisol A 24-acetate: alisol A: alisol C 23-acetate 7.2:0.6:2.8:3.0:6.4) and further validated by saline-loaded rats. This study demonstrated that TTE presented a notable diuretic effect by increasing Na⁺, K⁺, and Cl − displacements. The most suitable TTC compatible proportion of alisol B 23-acetate: alisol B: alisol A 24-acetate: alisol A: alisol C 23-acetate for diuretic activity was validated, and triterpenes were the material basis for the diuretic activity of AR.

[Development of a cell-based peroxisome proliferator-activated receptors (PPARs) screening model and its application for evaluation of triterpenoids isolate from Alismatis Rhizoma].

Peroxisome proliferators activated receptors (PPARs) are closely related to human chronic disease, such as diabetes mellitus and the other metabolic diseases. In this study, a cell-based PPARs (PPAR α/ß/γ) model was developed for the screening of PPARs agonists from Alismatis Rhizoma (AR). Firstly, 293T cells were transfected with the reconstructed plasmid pBind-PPAR (α, ß, or γ)-LBD and reporter gene pGL4.35, and the known PPARs agonists were used as the positive control (fenofibrate for PPARα, L165041 for PPARß, and rosiglitazone for PPARγ). The ability of activation for PPARs was evaluated by analyzing the expression value of luciferase. Afterward, the 14 pure triterpenoids isolate from AR were analyzed on the developed PPARα, PPARß and PPARγ screening assay method. The results showed that the compounds 5, 6, 7, 8, 13 and 14 from AR have the ability of activation for PPARα. The compounds 5 and 7 from AR have the ability of activation for PPARß. The compounds 6, 7, 8 and 12 from RA have the ability of activation for PPARγ.In this study, the compound 12 from AR were found to display significant activation on PPARγ for the first time. AR triterpenoids extracts had the ability of activation for PPARα, PPARß and PPARγ. The results suggested that triterpenoids extracts from AR were PPARα, PPARß and PPARγ agonists. The results will help to provide reference for clinical application of AR, and establish a model for PPARs on 293T cell, which can be used to screen and evaluate PPARs natural agonists.

A calculation method of plant similarity giving consideration to different plant features.

A method to compute the similarity between different plants is proposed, using features of a plant׳s topological structure and peripheral contour, as well as its geometry. The topological structures are described using tree graphs, and their similarity can be calculated based on the edit distance of these graphs. The peripheral contour of a plant is abstracted by its three-dimensional convex hull, which is projected in several directions. The similarity of the different projections is calculated by an algorithm to compute the similarity of two-dimensional shapes. The similarity of the geometrical detail is computed by considering the geometrical properties of different level branches. Finally the overall similarity between different plants is calculated by combining these different similarity measures. The validity of proposed method is evaluated by detailed experiments.

A novel UPLC-MS/MS method for sensitive quantitation of boldine in plasma, a potential anti-inflammatory agent: application to a pharmacokinetic study in rats.

Boldine is a potential anti-inflammatory agent found in several different plants. Published bioanalytical methods using HPLC with ultraviolet and fluorescent detection lacked enough sensitivity and required tedious sample preparation procedures. Herein, we describe the development of a novel ultra-high performance LC with MS/MS for determination of boldine in plasma. Boldine in plasma was recovered by liquid-liquid extraction using 1 mL of methyl tert-butyl ether. Chromatographic separation was performed on a C18 column at 45°C, with a gradient elution consisting of acetonitrile and water containing 0.1% (v/v) formic acid at a flow rate of 0.3 mL/min. The detection was performed on an electrospray triple-quadrupole MS/MS by positive ion multiple reaction monitoring mode. Good linearity (r(2) > 0.9926) was achieved in a concentration range of 2.555-2555 ng/mL with a lower limit of quantification of 2.555 ng/mL for boldine. The intra- and inter-day precisions of the assay were 1.2-6.0 and 1.8-7.4% relative standard deviation with an accuracy of -6.0-8.0% relative error. This newly developed method was successfully applied to a single low-dose pharmacokinetic study in rats and was demonstrated to be simpler and more sensitive than the published methods, allowing boldine quantification in reduced plasma volume.

Ultrasound/microwave-assisted extraction and comparative analysis of bioactive/toxic indole alkaloids in different medicinal parts of Gelsemium elegans Benth by ultra-high performance liquid chromatography with MS/MS.

Indole alkaloids are the main bioactive/toxic components in Gelsemium elegans Benth. To determine the distribution and contents of indole alkaloids in its different medicinal parts, a novel and rapid method using ultra-high performance LC (UPLC) with MS/MS has been established and validated with an optimized ultrasound/microwave-assisted extraction method. Four constituents, namely, humantenidine, humantenmine, gelsemine, and koumine, were simultaneously determined in 6 min. Chromatographic separation was achieved on an ultra-high performance LC BEH C18 column with a gradient mobile phase consisting of methanol and water (containing 0.1% formic acid both in methanol and water) at a flow rate of 0.3 mL/min. The detection was performed on a triple quadrupole electrospray MS/MS by positive ion multiple-reaction monitoring mode. All the analytes showed good linearity (r ≥ 0.9934) within a concentration range from 0.1-25 µg/mL with a LOQ of 25-50 ng/mL. The overall intra- and intervariations of four components were <4.7% with an accuracy of 97.3-101.3%. The analysis results showed that there were remarkable differences in the distribution and contents of four chemical markers in the roots, stems, and leaves of G. elegans Benth. The findings can provide necessary and meaningful information for the rational utilization of its resources.

Development of a sensitive and rapid UPLC-MS/MS method for the determination of koumine in rat plasma: application to a pharmacokinetic study.

A rapid, selective and sensitive method using UPLC-MS/MS was first developed and validated for quantitative analysis of koumine in rat plasma. A one-step protein precipitation with methanol was employed as a sample preparation technique. Plasma samples were separated on an Acquity UPLC BEH C18 column (50 × 2.1 mm, i.d. 1.7 µm) with a gradient mobile phase consisting of methanol with 0.1% (v/v) formic acid and water containing 0.1% (v/v) formic acid at a flow rate of 0.3 mL/min. Detection and quantification were performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring mode via positive eletrospray ionization. Good linearity (r > 0.9997) was achieved using weighted (1/x(2) ) least squares linear regression over a concentration range of 0.025-15 µg/mL with a lower limit of quantification of 0.025 µg/mL for koumine. The intra- and inter- precisions (relative standard deviation) of the assay at all three quality control samples were 5.6-14.1% with an accuracy (relative error) of 5.0-14.0%, which meets the requirements of the US Food and Drug Administration guidance. This developed method was successfully applied to an in vivo pharmacokinetic study in rats after a single intravenous dose of 20 mg/kg koumine.

Alisol B 23-Acetate Ameliorates Azoxymethane/Dextran Sodium Sulfate-Induced Male Murine Colitis-Associated Colorectal Cancer via Modulating the Composition of Gut Microbiota and Improving Intestinal Barrier.

Hunting for natural compounds that can modulate the structure of the intestinal flora is a new hotspot for colitis-associated cancer (CAC) prevention or treatment. Alisol B 23-acetate (AB23A) is a natural tetracyclic triterpenoid found in Alismatis rhizoma which is well known for dietary herb. Alismatis rhizoma is often used clinically to treat gastrointestinal diseases in China. In this study, we investigated the potential prevention of AB23A in male mouse models of azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced CAC. AB23A intervention alleviated the body weight loss, disease activity index, colon tumor load, tissue injury, and inflammatory cytokine changes in CAC mice. AB23A intervention leads to remarkable reductions in the activation of TLR, NF-κB and MAPK. AB23A significantly decreased the phosphorylation of p38, ERK, and JNK and up-regulated mucin-2 and the expression of tight junction proteins. The gut microbiota of AB23A-interfered mice was characterized with high microbial diversity, the reduced expansion of pathogenic bacteria, such as Klebsiella, Citrobacter, and Akkermansia, and the increased growth of bacteria including Bacteroides, Lactobacillus, and Alloprevotella. These data reveal that AB23A has the potential to be used to treat CAC in the future.

Alismatis Rhizoma Triterpenes Alleviate High-Fat Diet-Induced Insulin Resistance in Skeletal Muscle of Mice.

Alismatis rhizoma (AR), which is the dried rhizome of Alisma orientale (Sam.) Juz. (Alismataceae), is an important component of many famous Chinese formulas for hypoglycemic. This study aimed to evaluate the insulin resistance (IR) alleviating effects of AR triterpenes (ART) and ART component compatibility (ARTC, the mixture of 16-oxo-alisol A, 16-oxo-alisol A 23-acetate, 16-oxo-alisol A 24-acetate, alisol C, alisol C 23-acetate, alisol L, alisol A, alisol A 23-acetate, alisol A 24-acetate, alisol L 23-acetate, alisol B, alisol B 23-acetate, 11-deoxy-alisol B and 11-deoxy-alisol B 23-acetate) in high-fat diet-induced IR mice and plamitate-treated IR C2C12 cells, respectively. A dose of 200 mg/kg of ART was orally administered to IR mice, and different doses (25, 50, and 100 µg/ml) of ARTC groups were treated to IR C2C12 cells. IPGTT, IPITT, body weight, Hb1AC, FFA, TNF-α, MCP-1, and IR-associated gene expression (p-AMPK, p-IRS-1, PI3K, p-AKT, p-JNK, and GLUT4) were measured in IR mice. Glucose uptake, TNF-α, MCP-1, and IR-associated gene expression were also measured in IR C2C12 cells. Results showed that ART alleviated high-fat diet-induced IR in the skeletal muscle of mice, and this finding was further validated by ARTC. This study demonstrated that ART presented a notable IR alleviating effect by regulating IR-associated gene expression, and triterpenes were the material basis for the IR alleviating activity of AR.

Anti-proliferative activities of terpenoids isolated from Alisma orientalis and their structure-activity relationships.

This study aimed to isolate terpenoids from Alisma orientalis (Sam.) Juzep. and elucidate their antiproliferative activities, as well as structure-activity relationships. Fourteen protostane-type triterpenoids were isolated from the rhizome of A. orientalis. Among these triterpenoids, alisol A (1), alisol A 24-acetate (2), alisol B (3), alisol B 23-acetate (4), and alisol G (8) presented inhibitory effects on cancer cell lines tested. Compounds 3 and 4 showed the highest potential; IC50 values for HepG2, MDA-MB-231, and MCF-7 cells were 16.28, 14.47, and 6.66 µM for 3 and 18.01, 15.97, and 13.56 µM for 4, respectively. Based on these results, we concluded that the degree of C-16 oxidation and the double bond between C-13 and C-17 may be significant in anti-proliferative activities. Further study showed that 3 and 4 effectively induced apoptosis, as confirmed by flow cytometry. Increased intracellular calcium concentration and endoplasmic reticulum stress were detected after treatment with 4 in HepG2 cells. Although compounds 1 and 2 induced minimal apoptosis, they evidently delayed the G2/M phase in HepG2 cells. Further study showed that 1-4 also enhanced LC3II expression, indicating autophagy is occured.

[Effect of losartan on arterial blood pressure and unit discharging of neurons in LHb and MHb of rat].

AIM AND METHODS: To investigate the effect of 2 mg/kg and 10 mg/kg losartan intraperitoneally (i.p) on arterial blood pressure (AP) and heart rate (HR) in rat and the involvement in the activity of habenulas neurons. Glass micropipette was used to record any changes of unit discharging of neurons in LHb and MHb before and after losartan was intraperitoneally injected. RESULTS: AP and HR were not significantly changed by 2 mg/kg losartan (i.p). However, AP was apparently decreased by 10 mg/kg losartan (i.p), but HR was unchanged. After 10 mg/kg losartan (i.p), 66.66% (12/18) unit discharging of neurons in LHb were increased in frequency, and 61.90% (13/21) in MHb were decreased. CONCLUSION: AP of rat was significantly decreased by 10 mg/kg losartan (i.p). Depressor effect of losartan (i.p) was involved in the excision of neurons in LHb and the inhibition in MHb.