fraxin and fraxetin

Fraxini Cortex (also known as Qinpi, QP) has been used for the treatment of hyperuricemia with a significant difference on efficacy of QP from different regions. However, it`s still unknown whether proportion of components is the key and why same kind of herbs have different therapeutic effects. In this study, different sources of QP were collected from Shaanxi Qinpi extracts (SQPE), Henan Qinpi extracts (HQPE), Hebei Qinpi extracts (GQPE) provinces in China. Rat model of hyperuricemia with hypoxanthine combined with potassium oxonate were established to determine the levels of blood urea nitrogen (BUN), serum uric acid (SUA), urine uric acid (UUA) and creatinine (Cr). Hematoxylin-eosin staining (H&E) and Periodic Acid-Schiff staining (PAS) were performed for renal pathology while Western blot analysis and real-time PCR analysis for proteins and mRNA expression levels. High-performance liquid chromatograph (HPLC) was used for components and composition analysis. Our results demonstrated that QPE from different regions could alleviate hyperuricemia via increasing significantly the SCr and BUN levels whereas decreasing markedly UCr, SUA and UUA levels. Additionally, QPE could also improve the pathological changes of the kidneys. The protein and mRNA levels of urate reabsorption transporter 1 (URAT1) and glucose transporter 9 (GLUT9) were down-regulated by QPE treatment. SQPE hold a better activity on improving hyperuricemia and regulating URAT1 and GLUT9. HPLC analysis showed that the proportion of four components aesculin, aesculetin, fraxin, fraxetin were 9.002: 0.350: 8.980: 0.154 (SQPE); 0.526: 0.164: 7.938: 0.102 (HQPE); 12.022: 1.65: 0.878: 1.064 (GQPE). These data indicate that this proportion of effective components may be an important factor for efficacy of QP and had implications for the treatment of hyperuricemia.

Topics: Aesculus; Animals; Anion Transport Proteins; Biomarkers; Blood Urea Nitrogen; Coumarins; Creatinine; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Drugs, Chinese Herbal; Esculin; Gout Suppressants; Hyperuricemia; Kidney; Male; Monosaccharide Transport Proteins; Rats, Sprague-Dawley; Recovery of Function; Umbelliferones; Uric Acid

For the first time, a rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of fraxin and its metabolite, fraxetin, in rat plasma, using esculin as the internal standard (IS). The plasma samples were precipitated with methanol before separation on an Nova-Pak C18 column (150mm×3.9mm, 3μm) using a mobile phase consisting of 0.1% formic acid and methanol (55:45) at a flow rate of 0.8mL/min. The analytes were detected by multiple reaction monitoring in the negative ion mode with the mass transitions at m/z 368.9→ m/z 191.9 (fraxin), m/z 206.9→ m/z 191.8 (fraxetin) and m/z 339.0→ m/z 176.9 (esculin, IS). The results demonstrated that the calibration curves for both analytes have good linearity (r≥0.995) over a concentration range of 5.00-3000ng/mL. The assay was validated according to the regulatory bioanalytical guidelines and proved acceptable. The intra- and inter-day precisions (R.S.D.%) were within 10.9% for both analytes, whereas the deviation of assay accuracies (R.E.%) ranged from -5.3 to 1.0%. The method was successfully applied to a pharmacokinetic study after a single oral dose of fraxin at 50mg/kg to rats.

Topics: Animals; Calibration; Chromatography, Liquid; Coumarins; Rats; Reproducibility of Results; Tandem Mass Spectrometry

In this paper, a chromatographic method for isolation and purification of coumarin compounds from Cortex fraxinus was established by using Superose 12 as the separation media for the first time. The conditions for separation were optimized. Four kinds of coumarin compounds including aesuletin, aesculin, fraxetin and fraxin were obtained. The purity of these compounds were 98.5, 99.1, 97.9 and 97.3%, respectively, which were determined by HPLC area normalization method. The chemical structures of the separated compounds were identified according to (1)H and (13)C nuclear magnetic resonance data. The retention behavior of the separated coumarin compounds on Superose 12 was also discussed. The retention is based on a mixture of hydrogen bonding and hydrophobic interactions between the coumarin compounds and the residues of the cross-linking reagents used in the manufacturing process of Superose 12. The results of this paper indicate that Superose 12 is not only suitable for size-exclusion chromatography of proteins and other biological macromolecules but also for low-molecular-weight natural products.

Topics: Aesculus; Chromatography, Gel; Chromatography, High Pressure Liquid; Coumarins; Drugs, Chinese Herbal; Esculin; Hydrogen Bonding; Hydrophobic and Hydrophilic Interactions; Magnetic Resonance Spectroscopy; Molecular Structure; Sepharose; Umbelliferones

To establish a new quantitative method for simultaneous determination of multi-coumarins in Fraxini Cortex by using one chemical reference substance, and validate its feasibilities.. The new quality evaluation method, quantitative analysis of multi-components by singer-marker (QAMS), was established and validated with Fraxini Cortex. Four main coumarins were selected as analytes to evaluate the quality and their relative correlation factors (RCF) were determined by HPLC-DAD. Within the linear range, the values of RCF at 340 nm of aesculin to asculetin, fraxin and fraxetin were 1.771, 0.799, 1.409, respectively. And the contents of aesculin in samples of Fraxini Cortex were authentically determined by the external standard method, and the contents of the three other coumarins were calculated by their RCF. The contents of these four coumarins in all samples were also determined by the external standard method.. Within a certain range, the RCF had a good reproducibility (RSD 2.5%-3.9%). Significant differences were not observed between the quantitative results of two methods.. It is feasible and suitable to evaluate the quality of Fraxini Cortex and its Yinpian by QAMS.

Topics: Aesculus; Anticoagulants; Biomarkers; Coumarins; Drug Stability; Drugs, Chinese Herbal; Esculin; Feasibility Studies; Plant Extracts; Plants, Medicinal; Reproducibility of Results

To investigate the chemical constituents from the branch of Fraxinus sieboldiana, and evaluate their antioxidative activity.. The chemical constituents were isolated and purified by chromatographic techniques over silica gel, macroporous adsorbent resin, Sephadex LH-20, and preparative HPLC. Structures of the compounds were identified by spectroscopic methods. The antioxidant activity was evaluated by Fe(+2)-cystine induced rat liver microsomal lipid peroxidation.. Eight coumarins were obtained and their structures were elucidated as esculin (1) , esculetin (2), fraxin (3), fraxetin (4), 6, 7-di-O-beta-D-glucopyranosylesculetin (5), scopoletin (6), cleomiscosin D (7) and cleomiscosin B (8). At a concentration of 10(-6) mol x L(-1), compound 4 showed antioxidative activity inhibiting Fe(+2)-cystine induced rat liver microsomal lipid peroxidation with inhibitory rate of 60%.. Compounds 5, 7 and 8 were obtained from the genus Fraxinus for the first time. Compound 4 showed remarkable antioxidative activity, which was higher than that of VE (35%).

Topics: Animals; Antioxidants; Coumarins; Fraxinus; Lipid Peroxidation; Magnetic Resonance Spectroscopy; Microsomes, Liver; Rats; Scopoletin; Spectrometry, Mass, Electrospray Ionization; Umbelliferones

To investigate the chemical constituents of Fraxinus paxiana.. The chemical constituents were isolated and purified by chromatographic techniques and the structures of the compounds were identified with or by spectroscopic methods.. Fifteen compounds were obtained from the methanol extract of F. paxiana and their structures were elucidated as esculin (1), esculetin (2), fraxin (3), fraxetin (4), salidroside (5), osmanthuside H (6), liriodendrin (7), 3-(4-beta-D-glucopyranosyloxy-3-methoxy)-phenyl-2E-propenol (8), threo-syringylglycerol (9), euscaphic acid (10), 3-hydroxy-1-(4-hydroxy-3, 5-dimethoxyphenyl)-1-propanone (11), omega-hydroxypropioguaiacone (12), sinapyladehyde (13), betulinic acid (14) and mannitol (15).. All compounds were obtained from this plant for the first time.

Topics: Coumarins; Esculin; Fraxinus; Furans; Glucosides; Glycosides; Mannitol; Methanol; Phenols; Plant Bark; Triterpenes; Umbelliferones

By means of HIV gp41 binding affinity directed chromatographic fractionation, three phenylethanoid glycosides; calceolarioside A ( 1), calceolarioside B ( 2) and acteoside ( 3), along with four hydroxycoumarins; esculin ( 4), fraxin ( 5), fraxetin ( 6) and esculetin ( 7), and one lignan, (-)-olivil ( 8) were isolated from the n-butyl alcohol fraction of Fraxinus sieboldiana var. angustata. Among the isolated compounds, calceolarioside B ( 2) and esculetin ( 7) showed moderate binding affinity on HIV gp41 with IC 50 values of 0.1 mg/ml and 0.5 mg/ml, respectively. Calceolarioside A ( 1), calceolarioside B ( 2), acteoside ( 3), and (-)-olivil ( 8) were isolated for the first time from this plant.

Topics: Binding, Competitive; Caffeic Acids; Coumarins; Esculin; Fraxinus; Glucosides; Glycosides; HIV Envelope Protein gp41; HIV-1; Humans; Phenols; Phytotherapy; Plant Bark; Plant Extracts; Umbelliferones