Effects of undescribed iridoids in Patrinia punctiflora on insulin resistance in HepG2 cells.

Patrinia punctiflora is a medical and edible Chinese herb with high nutritional and medicinal value. The continuing study of its chemical constituents led to the isolation of six iridoids, which were previously unreported compounds, patriscabioins PU (1-6). Their structures were characterized and confirmed with NMR (1D & 2D), HRMS, IR and UV. Among them, compound 5 was screened to evaluate its insulin resistance activity on an IR-HepG-2 cell model. Compound 5 had no cytotoxicity compared with the control group and could promote glucose uptake in IR-HepG-2 cells. Through further mechanism studies, the undescribed compound 5 could increase the expression levels of PI-3 K, p-AKT, GLUT4 and p-GSK3ß proteins. Moreover, the expression of PEPCK and G6Pase proteins, which are key gluconeogenic enzymes, was also inhibited. Thus, compound 5 promotes the transfer of GLUT4 to the plasma membrane by activating the PI-3 K/AKT signaling pathway, at the same time, promotes glycogen synthesis and inhibits the onset of gluconeogenesis, which in turn ameliorates insulin resistance.

Structural Characterization and Anticoagulant Activity of a 3-O-Methylated Heteroglycan From Fruiting Bodies of Pleurotus placentodes.

Pleurotus placentodes, a fungus, belongs to the Pleurotaceae family. The aim of the present study was to characterize the structure of a novel polysaccharide from fruiting bodies of P. placentodes (PPp-W) and evaluate its anticoagulant activity in vitro. The high-performance liquid chromatography and GC-MS analysis indicated that PPp-W with a molecular weight of 27.4 kDa was mainly composed of mannose (17.56%), glucose (6.37%), galactose (44.89%), and fucose (1.22%) with a certain amount of 3-O-methyled galactose. SEM, XRD, and AFM combined with Congo red test revealed that PPp-W was an irregular curly sheet with triple-helix conformation. The FT-IR, methylation, and nuclear magnetic resonance analysis indicated that PPp-W contained→6)-α-D-Galp-(1→, →6)-3-O-Me-α-D-Galp-(1→and →2, 6)-α-D-Galp-(1→ as main chain, partially substituted at O-2 and O-6 by non-reducing ends of ß-D-Manp-(1→ and ß-L-Fucp-(1→ with a small amount of α-1,3-linked-Glcp in backbone. PPp-W could significantly prolong APTT (12.9 ± 0.42 s, p < 0.001) and thrombin time (39.9 ± 0.28 s, p < 0.01) compared with the control group (11.45 ± 0.071 s and 38.05 ± 0.21 s), which showed that PPp-W had anticoagulant activity. These studies suggested that PPp-W was a 3-O-methylated heteroglycan and might be suitable for functional foods and natural drugs as an anticoagulant ingredient, which provided a basis for the application of polysaccharides from P. placentodes.

CYPs-mediated drug-drug interactions on psoralidin, isobavachalcone, neobavaisoflavone and daidzein in rats liver microsomes.

The incubation system of CYP2E1 and CYP3A4 enzymes in rat liver microsomes was established to investigate the effects of psoralidin, isobavachalcone, neobavaisoflavone and daidzein from Fructus Psoraleae in vitro. The relevant metabolites were measured by the method of high performance liquid chromatography (HPLC), after probe substrates of 4-nitrophenol, testosterone and the drugs at different concentrations were added to the incubation systems. In addition, real-time RT-PCR was performed to determine the effect of psoralidin, neobavaisoflavone and daidzein on the mRNA expression of CYP3A4 in rat liver. The results suggested that psoralidin, isobavachalcone and neobavaisoflavone were Medium-intensity inhibitors of CYP2E1 with Ki values of 2.58, 1.28 and 19.07 µM, respectively, which could inhibit the increase of CYP2E1 and reduce diseases caused by lipid peroxidation. Isobavachalcone (Ki = 37.52 µM) showed a weak competitive inhibition on CYP3A4. Psoralidin and neobavaisoflavone showed obvious induction effects on CYP3A4 in the expression level of mRNA, which could accelerate the effects of drug metabolism and lead to the risk of inducing DDIs and serious adverse reactions. The results could be used for guideline of Fructus Psoraleae in clinic, which aimed to calculate the drug toxicity by studying the drug-drug interactions caused by the induction and inhibition of CYP450.

A novel polysaccharide from Malus halliana Koehne with coagulant activity.

A novel polysaccharide in Malus halliana Koehne, named MHP-W, was isolated and purified by DEAE-52 cellulose and Sephadex G-100 columns. Structural features were identified by high performance size-exclusion chromatography (HPSEC), fourier transform infrared (FT-IR) spectrometer, gas chromatography (GC) and (1D & 2D) NMR Spectroscopy. Structural characterization showed that the molecular weight of MHP-W was 353 kDa composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 2.59: 0.15: 0.23: 0.25: 9.70. The existence of ß-glycosidic bond between the sugar units was confirmed by FT-IR and NMR spectroscopy. The effects of MHP-W on active part thrombin time (APTT), protothrombin time (PT), thrombin time (TT), and fibrinogen (FIB) were screened by a cell-based coagulation activity model. MHP-W could significantly shorten TT (p < 0.001) and increase FIB (p < 0.05) as compared with the control group. The results showed that MHP-W promoted bloodclotting through endogenous and exogenous coagulation pathways as well as increasing fibrinogen content, which indicated that MHP-W had procoagulant activities in vitro.

Chaetomadrasins A and B, Two New Cytotoxic Cytochalasans from Desert Soil-Derived Fungus Chaetomium madrasense 375.

Two new cytochalasans, Chaetomadrasins A (1) and B (2), along with six known analogues (3-8), were isolated from the solid-state fermented culture of desert soil-derived Chaetomium madrasense 375. Their structures were clarified by comprehensive spectroscopic analyses, and the absolute configurations of Compounds 1 and 2 were confirmed by electronic circular dichroism (ECD) and calculated ECD. For the first time, Chaetomadrasins A (1), which belongs to the chaetoglobosin family, is characterized by the presence of all oxygen atoms in the form of Carbonyl. Chaetomadrasin B (2) represents the first example of chaetoglobosin type cytochalasan characterized by a hydroxy unit and carbonyl group fused to the indole ring. Compounds 1 and 2 displayed moderate cytotoxicity against HepG2 human hepatocellular carcinoma cells.

ZnO nanotubes supported molecularly imprinted polymers arrays as sensing materials for electrochemical detection of dopamine.

In this study, ZnO nanotubes (ZNTs) were prepared onto fluorine-doped tin oxide (FTO) glass and used as supports for MIPs arrays fabrication. Due to the imprinted cavities are always located at both inner and outer surface of ZNTs, these ZNTs supported MIPs arrays have good accessibility towards template and can be used as sensing materials for chemical sensors with high sensitivity, excellent selectivity and fast response. Using K3[Fe(CN)6] as electron probe, the fabricated electrochemical sensor shows two linear dynamic ranges (0.02-5µM and 10-800µM) towards dopamine. This proposed electrochemical sensor has been applied for dopamine determination with satisfied recoveries and precision. More complex human urine samples also confirmed that the proposed method has good accuracy for dopamine determination in real biological samples. These results suggest potential applicability of the proposed method and sensor in important molecule analysis.

Purification, characterization and procoagulant activity of polysaccharides from Angelica dahurice roots.

Five polysaccharides, namely ADPs-1a, ADPs-1b, ADPs-2, ADPs-3a and ADPs-3b, were extracted from Angelicae dahuricae Radix, purified, and identified by high performance gel permeation chromatography (HPSEC), gas chromatography (GC), Fourier transform infrared (FT-IR) spectrometer and nuclear magnetic resonance spectra (NMR), including the determination of procoagulant activity in vitro. The average molecular weight (Mw) of the polysaccharides was 153,800, 8312, 111,700, 3766 and 96,680 g/mol, respectively. Coagulation assays indicated that ADPs-1b, ADPs-2, ADPs-3a and ADPs-3b had procoagulant activities. ADPs-1b exerted the procoagulant activities through intrinsic pathway, extrinsic pathway and increased the content of FIB in vitro. ADPs-2 exerted the procoagulant activities through intrinsic pathway and extrinsic pathway. ADPs-3a had procoagulant activities and the activity was associated with the intrinsic pathway and increased the content of FIB. ADPs-3b exerted the activities through extrinsic pathway and increased the content of FIB.

Antithrombotic Effect and Mechanism of Radix Paeoniae Rubra.

The compounds of Radix Paeoniae Rubra (RPR) were isolated and identified by bioassay-guided method, and antithrombotic effects and mechanism were investigated by the acute blood stasis rat model. The RPR extract was evaluated by APTT, TT, PT, and FIB assays in vitro. Results indicated that RPR extract exhibited the anticoagulant activity. In order to find active compounds, six compounds were isolated and identified, and four compounds, paeoniflorin (Pae), pentagalloylglucose (Pen), albiflorin (Ali), and protocatechuic acid (Pro), exhibited the anticoagulant activity in vitro. Therefore, the antithrombosis effects of RPR extract and four active compounds were investigated in vivo by measuring whole blood viscosity (WBV), plasma viscosity (PV), APTT, PT, TT, and FIB. Meanwhile, the levels of TXB2, 6-Keto-PGF1α , eNOS, and ET-1 were detected. Results suggested that RPR extract and four active compounds had the inhibition effect on thrombus formation, and the antithrombotic effects were associated with the regulation of vascular endothelium active substance, activating blood flow and anticoagulation effect.

Chemical constituents and coagulation activity of Agastache rugosa.

BACKGROUND: In the Chinese traditional medicine, plant of Agastache rugosa (Fisch. & C.A. Mey.) Kuntze (A. rugosa) has been used to treat nausea, vomiting and dispel damp. However, currently, few reports about the chemical constituents, especially the non-volatile components of A. rugosa are available. METHODS: Through separation with various column chromatographies to elucidate the chemical constituents of A. rugosa, the biological activities of the major constituents were investigated. The extracts and main constituents of A. rugosa were evaluated for their anticoagulant effects by assaying the activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT) and fibrinogen (FIB) in vitro. RESULTS: Seven known compounds (namely compounds 1-7) were isolated from the aerial parts of A. rugosa. They were identified as methyl hexadecanoate (1), ß-sitosterol (2), acacetin (3), ursolic acid (4), apigenin (5), protocatechuic acid (6) and tilianin (7), respectively. Compounds 1 and 6 were isolated from the genus Agastache for the first time, and compound 4 was obtained from the plants for the first time. The results showed that the extract of A. rugosa had a significant procoagulant activity by shortening the time of PT (P < 0.001) and increasing FIB content (P < 0.001), as compared with Vitamin K1. While its major constituents acacetin and tilianin exhibited significant anticoagulant activities by prolonging the times of PT, APTT, TT and reducing FIB content (P < 0.001), as compared with blank control group. CONCLUSIONS: The total extract of A. rugosa possessed significant procoagulant activity, while its main components, acacetin and tilianin possessed significant anticoagulant activities. Further investigation should be pursued to find out the bioactivity components responsible for the procoagulant action of the plant.

Molecularly imprinted solid phase extraction method for simultaneous determination of seven nitroimidazoles from honey by HPLC-MS/MS.

In this work, a selective sample cleanup procedure that combined molecular imprinting technique with solid phase extraction was developed for the simultaneous extraction of the seven nitroimidazoles (NMZs) from honey samples. The molecular imprinting polymers for NMZs were prepared through bulk polymerization method using 2-methyl-5-nitroimidazole as template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross linking agent. The obtained molecular imprinting polymers showed high affinity to template molecule and was used as selective sorbent for simultaneously selective extraction of the seven NMZs from honey matrix. An off-line molecularly imprinted solid phase extraction (MISPE) method followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) for simultaneous determination of the seven NMZs from honey samples was also established. The proposed method was validated at 1.0, 2.0 and 10.0µg/kg, obtaining recoveries in the range of 79.7-110%, with repeatability and interday precision values (expressed as relative standard deviation) ≤11.4% and ≤15.2%, respectively. Limits of quantification for different NMZs were 1.0µg/kg, which were always below the minimum required performance limits established by the European Community Reference Laboratories (Commission Decision 2002/657/EC). It was demonstrated that this proposed MISPE-HPLC-MS-MS method could be applied to direct determination of NMZs from honey samples.

Effects of Flavonoids in Lysimachia clethroides Duby on the Activities of Cytochrome P450 CYP2E1 and CYP3A4 in Rat Liver Microsomes.

Incubation systems were established to investigate the effects of quercetin, kaempferol, isoquercitrin and astragalin in Lysimachia clethroides Duby on the activities of CYP2E1 and CYP3A4 in rat liver microsomes in vitro. Probe substrates of 4-nitrophenol and testosterone as well as flavonoids at different concentrations were added to the incubation systems. After incubation, a validated high performance liquid chromatography (HPLC) method was applied to separate and determine the relevant metabolites. The results suggested that kaempferol exhibited a weak inhibition of CYP2E1 activity with an IC50 of 60.26 ± 2.54 µM, while quercetin and kaempferol caused a moderate inhibition of CYP3A4 activity with IC50 values of 18.77 ± 1.69 µM and 32.65 ± 1.32 µM, respectively. Isoquercitrin and astragalin had no effects on the activities of either CYP2E1 or CYP3A4. It could be speculated from these results that the inhibitory effects of quercetin and kaempferol on the activities of CYP2E1 and CYP3A4 could be the mechanisms underlying the hepatoprotective effects of L. clethroides.

[Spectrum-effect relationship in antioxidant activity of Ligustri Lucidi Fructus based on DPPH, ABTS and FRAP assays].

Characteristic chromatogram of Ligustri Lucidi Fructus which were processed by heat treatment with different temperatures and times was developed by HPLC. DPPH, ABTS and FRAP assays were performed to determine the antioxidant activity. The spectrum-effect correlation was studied using Partial Least Squares(PLS)to explore the active ingredients of Ligustri Lucidi Fructus by investigating the relationship between HPLC spectrum and antioxidant activity. S1, S2, S15, S24, S27, S29, S32, S33 and S35 were characteristic compounds in 35 matching characteristic chromatograms which were positive relationship with scavenging DPPH free radical activity. S1, S2, S5, S8, S16, S27 and S33 were significantly positively related to scavenge ABTS free radical activity. S12, S20, S22, S28, S30, S31, S32 and S34 were significantly positively related to restore Fe³âº activity. Among the chromatographic peaks, S1, S2, S27 and S33were positively related to scavenge DPPH free radical and ABTS free radical activity, and S32 was positively related to scavenge DPPH free radical and restore Fe³âº activity. S3, S19, S21, S22, S23, S33 and S34 were determined as salidroside, luteolin-7-O-glucoside, specnuezhenide, oleuropein, ligustroflavone, luteolin andapigenin, respectively. The results showed that although specnuezhenide and salidroside were stipulated index compounds to evaluate the quality of Ligustri Lucidi Fructus, the Ligustri Lucidi Fructus pharmcodynamic effect did not depend on the contents of those index components. The quality of traditional Chinese medicines(TCMs)should be determined by the compound groups associated with pharmcodynamic effect.

[Research progress on chemical compounds and pharmacological effects of Caesalpinia].

Consult literature, the chemical composition of the type of system Caesalpinia plants were summarized and discussed in detail its pharmacological effects. The genus contains major chemical components of high isoflavones, chalcones and diterpenoids, pharmacological effects inhibit melanin production, anti-inflammatory, antioxidant, antibacterial, immune regulation, and further research in this genus offer reference.

[Simultaneous determination of quercitrin, phloridzin and 3-hydroxyl phloridzin in leaves of Malus halliana by ultrasound-assisted ionic liquid-reversed phase liquid chromatography].

To establish a method for the simultaneous determination of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of Malus halliana by ultrasonic-assisted ionic liquid coupled with RP-HPLC. An Agilent TC-C18 (4.6 mm×250 mm, 5 µm) column was used, with the mobile phase of acetonitrile and 1% phosphoric acid-water (20∶80) by gradient elution at the detection wavelength of 270 nm. The flow rate was 0.8 mL•min⁻¹, and chromatographic column temperature was controlled at the room temperature. Under the optimized conditions, the linear ranges for phloridzin, 3-hydroxy phloridzin and quercitrin were 0.9-112.5 µg (r = 0.999 6), 0.093 2-11.65 µg (r = 0.999 1) and 0.097 2-12.15 µg (r = 0.999 8), respectively. The average recoveries of the three constituents were 99.35%, 98.80% and 98.19%, respectively. The method was environmental friendly, rapid, accurate and highly reproducible, and so suitable for the quantitative analysis of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of M. halliana.

[Effect of heating treatment on stability of two coumarins in Angelica dahurica and activity of tyrosinase].

To study the heating treatment of Angelica dahurica under different temperature and time conditions on the stability of coumarins and tyrosinase activity. HPLC method was used to determine the contents of imperatorin and isoimperatorin, and tyrosinase activity was assayed by measuring the oxidation rate of L-DOPA in vitro. After heated, the contents of imperatorin increased. Expect for being heated at 90 ℃ for 2 h, the content of isoimperatorin was higher than crude one. Before and after being heated, A. dahurica showed an activating effect on tyrosinase. In the same temperature and time conditions, the activation rate increased with the rise of concentration of tyrosinase extracts. Heating process for A. dahurica could change the contents of imperatorin and isoimperatorin, mainly increasing their concentrations.

Simultaneous determination of alizarin and rubimaillin in Rubia cordifolia by ultrasound-assisted ionic liquid-reversed phase liquid chromatography.

Four kinds of ionic liquids were adopted to analyze the content of rubimaillin and alizarin in Rubia cordifolia roots with ultrasonic-assisted extraction coupled with HPLC. The chromatographic column, Purospher star RP-C18 (4.6 mm x 250 mm, 5 microm), was used. Methanol and 0.4% acetic acid-water as mobile phase with flow rate at 0.85 mL min(-1), gradient elution, detection wavelength at 250 nm, chromatographic column temperature was controlled at room temperature. The result showed that rubimaillin and alizarin had the highest extraction yield when the [ HMIM] PF6methanol solution concentration of 0.6 mol x L(-1) as extraction solvent and the conditions were solid-liquid ratio of 1:80 (g x mL(-1)). Under the optimal extraction conditions, the content of alizarin from 0.01 to 0.04 microg showed a good linearity (r = 0.9999), the average recovery was 97.12%, the content of rubimaillin from 0.41 to 1.35 microg showed a good linearity (r = 0.9999), the average recovery was 98.10%. This experiment adopted environmentally friendly reagent as extraction solvent, the extraction efficiency was improved, and the environmental pollution caused by organic solvent was avoided, the harm of human body aslo was reduced. This method was simple and reliable, its repeatability was also very good, which had an important significance in the study of traditional Chinese medicine active ingredient extraction methods.

[Advance on chemical compounds of Ainsliaea genus].

Plants in Ainsliaea genus, belongs to Compositae family, are traditional Chinese medicine and widely used in folk. These plants contain various types of chemical components, and main components are sesquiterpene lactone and its glycosides. In addition, there are triterpenoids, flavonoids, steroids, phenolic acid, long chain fatty acid and volatile oils. Recently, much attention has been payed to varlous research of A. fragrans. This paper reviewed and summarized the chemical components to provide the theoretical basis for the use of Ainsliaea.

[Analysis of four flavonoids in Lysimachia clethroides using ionic liquid-assisted extraction].

In order to established a method for simultaneous determination of isoquercitrin, astragaline, quercetin and kaempferol in Lysimachia clethroides, the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([HMIM]PF6) methanol was used as the ultrasound-assisted extraction solvent combing with RP-HPLC. A Purospher star RP-C1 column was used with the mobile phase of aceto- nitrile, methanol and 0. 4% phosphate acid by gradient elution at the detection wavelength of 360 nm. The flow rate was 0.7 mL x min(-1), and the column temperature was the room temperature. Under the optimized conditions, the linear ranges were 2.54 x 10(-2)-2. 54, 2.50 x 10(-2)- 2.50, 1.54 x 10(-3)-0.154, 1.49 x 10(-3)-0.149 microg for isoquercitrin, astragaline, quercetin and kaempferol, respectively. The average recoveries of the four constituents were 101.1%, 98.90%, 101.0%, 101.6%, respectively. The method was green, simple, rapid and accurate, and provided a valid method for analysis of isoquercitrin, astragaline, quercetin and kaempferol in L. clethroides.

[Determination of oleanic acid and paeoniflorin in Paeonia lactiflora by ultrasound-assisted ionic liquid-reversed phase liquid chromatography].

Four kinds of ionic liquids [BMIM] Br, [BMIM] BF4, [BMIM] PF6, [HMIM] PF6 were used to analyze the content of oleanic acid and paeoniflorin in Paeonia lactiflora with ultrasonic-assisted extraction coupled with HPLC. The chromatographic column, Purospher star RP-C18 (4.6 mm x 250 mm, 5 µm), was used. Acetonitrile and water (90:10) as mobile phase was used to determine the content of oleanic acid with a gradient elution and flow rate at 1.00 mL · min(-1), detection wavelength at 210 nm, chromatographic column temperature at room temperature. Paeoniflorin content was determined using acetonitrile and water (18:82) as mobile phase with a gradient elution and flow rate at 1.00 mL · min(-1), detection wavelength at 250 nm, the chromatographic column temperature at room temperature. The result show that oleanic acid has the highest extraction yield when the conditions are solid-liquid ratio of 1:80 (g · mL(-1)), and the [BMIM] Br methanol solution concentration of 0.6 mol · L(-1). Under the optimal extraction conditions, the content of oleanic acid from 0.24 to 3.76 µg showed a good linearity (r = 0.9999), the average recovery was 97.20%. Paeoniflorin has the highest extraction yield when the conditions are solid-liquid ratio of 1:130 (g · mL(-1)), and the [C4 MIM] PF6 methanol solution concentration of 0.6 mol · L(-1). Under the optimal extraction conditions, paeoniflorin content from 0.42 to 4.20 µg showed a good lin- earity (r = 1.000), the average recovery was 98.84%. This method is simple and reliable, its repeatability is also very good. It has important significance in the study P. lactiflora of ionic liquid microextraction.

Antioxidant activity in vitro and hepatoprotective effect of Phlomis maximowiczii in vivo.

BACKGROUND: A number of medicinal plants and there compounds played a major role in the treatment of hepatic disorders. They were widely used for the treatment of these disorders, and oxidant stress injury was one of the liver injury mechanisms. The present study evaluated the antioxidant activity and the hepatoprotective effect of each extracts of Phlomis maximowiczii. MATERIALS AND METHODS: The antioxidant activity was assayed by the methods of ABTS, FRAP and DPPH in vitro. Hepatoprotective effect of P. maximowiczii extracts was examined using carbon tetrachloride-induced acute liver injury in mice. RESULTS: P. maximowiczii n-butanol (PMBU) extract, ABTS (IC50=18.96 µg/mL), DPPH (IC50=25.15 µg/mL), and FRAP (RACT50=2775.6±144.18 µmol/g), showed higher scavenging capacity than that of P. maximowiczii ethyl acetate (PMEA). The n-butanol extract could significantly reduce the level of GPT, GOT and MDA (P<0.05, P<0.001 and P<0.001, respectively) and increase the level of SOD (P<0.001), respectively. CONCLUSION: The antioxidant activity of n-butanol extract in vitro was related with the level of MDA and SOD in vivo, and hepatoprotective effect of n-butanol extract also had relationship with its antioxidant activity in vivo.