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ABSTRACT: Puerarin has multiple pharmacological effects and is widely prescribed for patients with cardiovascular diseases including hypertension, cerebral ischemia, myocardial ischemia, diabetes mellitus, and arteriosclerosis. We have successfully prepared puerarin-loaded solid lipid nanoparticles (Pue-SLNs) for oral administration. Pue-SLNs are prepared using monostearin, soya lecithin, and poloxamer 188. SLNs may alter the course of puerarin absorption predominantly to and through lymphatic routes and regions, presumably following a transcellular path of lipid absorption, especially by enterocytes and polar epithelial cells of the intestine. The alteration of absorption might influence the metabolic profile of puerarin when incorporated into SLNs. In the present study, we investigated the metabolic profile of puerarin in rat plasma and urine using rapid resolution liquid chromatography-tandem mass spectrometry after a single-dose intragastric administration of Pue-SLNs in comparison with puerarin suspension. Two glucuronidated metabolites of puerarin, puerarin-4'-O-glucuronide and puerarin-7-O-glucuronide, were detected in rat plasma and urine after intragastric administration of Pue-SLNs, with the latter acting as the major metabolite. Similar results were found in rat plasma and urine after intragastric administration of puerarin suspension. The results suggest that incorporation of puerarin into SLNs does not change either the position of glucuronidation or the metabolic pathway of puerarin in rats.
International Journal of Nanomedicine 01/2013; 8:933-40. · 3.13 Impact Factor
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ABSTRACT: To study the histomorphological and immunochemical characteristics of benign prostate hyperplasia (BPH) induced by urogenital sinus (UGS) implantation in the rat model.
We randomized 32 seven-week old male SD rats into a sham operation control and three (2-, 3- and 6-week) UGS model groups. We made the UGS model by implanting two urogenital sinuses from homogeneous male rat embryos into the host rats' right anterior lobe, and killed the model rats 2, 3 and 6 weeks later for measuring the wet weight, volume and micromorphological parameters of the right anterior lobe and detecting the factors expressed in the epithelium, stroma and smooth muscle by immunochemistry.
The model rats showed significant increases in the wet weight, volume and relevant indexes of the right anterior lobe (P < 0.05), as well as in the proportion of stromal area and relative stromal volume (P < 0.1) with the prolonging of time. The mean stromal proportion of the 3-week models was as high as 75.32%. There was also a time-dependent increase in the relative total volume of epithelia in the model groups. The luminal area and the proportions of the luminal and epithelial volumes were obviously reduced in the model rats as compared with the sham operation controls. Pan-cytokeratin positive particles were located in epithelial cells, vimentins abundantly expressed in mesenchymocytes, and alpha-smooth muscle actins expressed around the lumen of the gland.
BPH induced by urogenital sinus implantation in rats is typically stromal hyperplasia, and the locations of related factors are similar to those in men with BPH.
Zhonghua nan ke xue = National journal of andrology 08/2012; 18(8):703-9.
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ABSTRACT: Puerarin has multiple pharmacological effects and is widely prescribed for patients with cardiovascular diseases, including hypertension, cerebral ischemia, myocardial ischemia, diabetes mellitus, and arteriosclerosis. While puerarin is a useful therapeutic agent, its mechanisms of action have not been well defined. Understanding puerarin metabolism, in particular its interactions with metabolizing enzymes, will contribute to our understanding of its toxic and therapeutic effects and may help to elucidate potential negative drug-drug interactions. In this study, the major metabolite of puerarin was obtained from the urine of rats administered puerarin, by a semi-preparative high-performance liquid chromatography method. The major metabolite was identified as puerarin-7-O-glucuronide. In vitro, we used a UDP-glucuronosyltransferase (UGT) reaction screening method with 12 recombinant human UGTs to demonstrate that formation of puerarin-7-O-glucuronide was catalyzed by UGT1A1, 1A9, 1A10, 1A3, 1A6, 1A7, and 1A8. UGT1A1, 1A9, and 1A10 significantly catalyzed puerarin-7-O-glucuronide formation, and the activity of UGT1A1 was significantly higher than those of 1A9 and 1A10. The V (max) of UGT1A1 was two- to threefold higher than the levels of UGT1A9 or 1A10, with a lower K ( m ) value and a higher V (max)/K ( m ) value. The kinetics of puerarin-7-O-glucuronide formation catalyzed by UGT1A1 were similar to those of the pooled human liver microsomes (HLMs), with V (max) values of 186.3 and 149.2 pmol/min/mg protein, and K ( m ) values of 811.3 and 838.9 μM, respectively. Furthermore, bilirubin and β-estradiol, probe substrates for UGT1A1, significantly inhibited the formation of puerarin-7-O-glucuronide in HLMs.
Archive für Toxikologie 05/2012; 86(11):1681-90. · 4.67 Impact Factor
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ABSTRACT: A highly sensitive and specific method of rapid resolution liquid chromatography tandem mass spectrometry (RRLC-MS/MS) in positive ionization mode has been developed and validated for pharmacokinetic study of puerarin in rat plasma. Chromatography was carried out on a Zorbax XDB C18 reversed-phase column using a mobile phase comprising a mixture of methanol and 0.05% acetic acid in water (35:65, v/v) with a flow rate of 0.3 mL/min from 0 min to 5.4 min and then 0.6 mL/min from 5.41 min to 12 min. The mass spectrometer operated in ESI positive ionization mode. Multiple reaction monitoring (MRM) was used to measure puerarin and tectoridin (internal standard). The method was sensitive with a detection limit of 0.33 ng/mL. A good linear response was observed over a range of 10-2000 ng/mL in rat plasma. The inter- and intra-day precision ranged from 2.97% to 7.52% and accuracy from 93.70% to 101.60%. This validated method was applied successfully to a pharmacokinetic study in rat plasma after intravenous administration of puerarin. The main pharmacokinetic parameters were as follows: AUC(0→t) 45.37±13.19 (mgh/L), AUC(0→∞) 47.03±14.78 (mgh/L), MRT 1.03±0.46 (h), T(1/2) 1.31±0.31 (h), V(ss) 0.09±0.02 (L), V(z) 0.17±0.04 (L), Cl 0.10±0.04 (L/h).
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 06/2011; 879(19):1497-501. · 2.78 Impact Factor
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ABSTRACT: Puerarin has various pharmacological effects; however, poor water-solubility and low oral bioavailability limit its clinical utility. A delivery system of solid lipid nanoparticles could enhance its oral absorption. The objective of this study was to investigate the pharmacokinetics, tissue distribution and relative bioavailability of puerarin in rats after a single dose intragastric administration of puerarin solid lipid nanoparticles (Pue-SLNs). The puerarin concentrations in plasma and tissues were determined by rapid resolution liquid chromatography electrospray ionization-tandem mass spectrometry. The C(max) value of puerarin after the administration of Pue-SLNs was significantly higher than that obtained with puerarin suspension (0.33±0.05 μg/mL vs. 0.16±0.06 μg/mL, P<0.01). The T(max) value after the administration of the Pue-SLNs was significantly shorter than that after puerarin suspension administration (40±0 min vs. 110±15.49 min, P<0.01). The AUC(0→t) values of puerarin were 0.80±0.23 mg h/L, and 2.48±0.30 mg h/L after administration of the puerarin suspension and Pue-SLNs, respectively. Following administration of the Pue-SLNs, tissue concentrations of puerarin also increased, especially in the target organs such as the heart and brain. These data suggest that SLNs are a promising delivery system to enhance the oral bioavailability of puerarin.
International journal of pharmaceutics 03/2011; 410(1-2):138-44. · 2.96 Impact Factor
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ABSTRACT: The α(1A)-adrenergic receptor (α(1A)-AR) antagonist is useful in treating benign prostatic hyperplasia, lower urinary tract symptoms, and cardiac arrhythmia. Three-dimensional quantitative structure-activity relationship (3D-QSAR) studies were performed on a set of α(1A)-AR antagonists of N-aryl and N-nitrogen class. Statistically significant models constructed from comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were established based on a training set of 32 ligands using pharmacophore-based molecular alignment. The leave-oneout cross-validation correlation coefficients were q(2) (CoMFA) = 0.840 and q(2) (CoMSIA) = 0.840. The high correlation between the cross-validated/predicted and experimental activities of a test set of 12 ligands revealed that the CoMFA and CoMSIA models were robust (r(2) (pred) (/CoMFA) = 0.694; r(2) (pred) (/CoMSIA) = 0.671). The generated models suggested that electrostatic, hydrophobic, and hydrogen bonding interactions play important roles between ligands and receptors in the active site. Our study serves as a guide for further experimental investigations on the synthesis of new compounds. Structural modifications based on the present 3D-QSAR results may lead to the discovery of other α(1A)-AR antagonists.
International Journal of Molecular Sciences 01/2011; 12(10):7022-37. · 2.60 Impact Factor
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ABSTRACT: To investigate the effects of puerarin solid lipid nanoparticle on fore brain ischemic-reperfusion injury in gerbils and it's mechanisms.
Gerbils were randomly divided into 4 groups: sham group, cerebral ischemia-reperfusion injury group, puerarin solid lipid nanoparticle group and puerarin injection control group. The gerbils' cerebral ischemia-reperfusion injury model was constructed with ligating bilater carotids method. The histomorphology and Bcl-2, Caspase-3 and HSP70 expressions were detected by HE dyeing and immunohistochemical method.
After 24 h ischemia and reperfusion in gerbils, the level of Bcl-2 and HSP70 expressions in puerarin solid lipid nanoparticle group increased (P < 0.01) compared with the ischemic-reperfusion model group, and the level of Caspase-3 expression decreased (P < 0.01). The same results was consistent in puerarin injection control group.
Puerarin solid lipid nanoparticle group can protect the cerebral ischemia-reperfusion injury in gerbils, which may be related to the upregulation of Bcl-2 and HSP70 expression and downregulation of Caspase-3 expression.
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials 12/2010; 33(12):1900-4.
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ABSTRACT: Computer aided drug discovery for selective antagonism effects on alpha(1A) subtypes of G-protein coupled receptors are important in the treatment of benign prostatic hyperplasia (BPH). Ligand-based pharmacophore models of N-Aryl and N-Heteroaryl piperazine alpha(1A)-antagonists were developed using two separate training sets. Pharmacophore models were generated using the flexible align method within the GALAHAD module, implemented in SYBYL8.1 software. The most significant pharmacophore hypothesis, characterized by the conflicting demands of maximizing pharmacophore consensus, maximizing steric consensus, and minimizing energy, consisted of one positive nitrogen center, one donor atom center, two acceptor atom centers, and two hydrophobic groups. The most active compound in each class training set showed a good fit with all features of the pharmacophore proposed. The resulting models also had something in common with the hypothesis using the Catalyst software reported in other publications. These alpha(1A) pharmacophore models could predict compounds well, both in the training set and the test set. The pharmacophore models were also validated by an external dataset using a portion of the ZINC database. A 3D-QSAR model using the pharmacophore model to align the compounds was established in this study. The CoMFA model with the cross-validated q(2) value of 0.735 revealed that the model was valid. Our research provides a valuable tool for designing new therapeutic compounds with desired biological activity.
Journal of molecular graphics & modelling 09/2010; 29(2):126-36. · 2.17 Impact Factor
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ABSTRACT: Puerarin is a major active ingredient of Pueraria radix. Puerarin may exert its medicinal functions in part via its metabolites. In this study, we identified these metabolites to better understand and elucidate puerarin's metabolic pathway. Puerarin was intravenously administered to rats and then metabolites in plasma samples were identified by rapid resolution liquid chromatography electrospray ionization-collision induced dissociation tandem mass spectrometry (RRLC-ESI-CID-MS/MS). Chromatography was conducted on a Zorbax SB C18 column (2.1x100 mm, 1.8 microm) at 30 degrees C, with a gradient mobile phase consisting of 0.05% formic acid and acetonitrile, a flow rate of 0.2 mL min(-1), and a total run time of 14 min. MS/MS acquisition parameters were as follows: positive ionization mode, dry gas: nitrogen, 10 L min(-1), dry temperature: 350 degrees C, nebulizer: 40 psi, capillary: -3500 V, scan range: 250-800. The autoMS, manual, or multiple reaction monitoring mode was selected as required. Two glucuronidated metabolites of puerarin (M1 and M2) were detected. M1 and M2 are presumed to be puerarin-7-O-glucuronide and puerarin-4'-O-glucuronide, respectively, and M2 likely is suspected to be the major metabolite because it represented the predominate peak. Kinetic studies of metabolites demonstrated that M1 and M2 were detected in rat plasma at 5 min after intravenous administration of puerarin, the levels of M1 and M2 then reached their peaks at 10-15 and 15-30 min, respectively. The metabolic profiles were similar in rat liver and intestine investigated by in situ liver and intestine perfusion, indicating that no metabolic regioselectivity of puerarin occurs in the two organs.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 12/2009; 878(3-4):363-70. · 2.78 Impact Factor
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ABSTRACT: According to the results of activity-structure relationship (SAR) studies of alpha1-adrenoceptor antagonists hydantoin-phenylpiperazine and benzimidazo-arypiperazine derivatves, to design and synthesize a series of novel phenylpiperazine alpha1-adrenoceptor antagonists with more potent vasorelaxant activity, active metabolites of naftopidil were used as lead compounds. Ten novel R,S-1-substituted phenyl-4-[3-(naphthal-yl-oxy)-2-hydroxy propyl]-piperazine were designed and synthesized, their vasorelaxant activity was evaluated by calculating inhibition rate of phenylephrine-induced vasocontration of rabbit artery trips. Five compounds exhibited vasorelaxant activity, and compound 16 showed significant vasorelaxant activity in vitro. At 0.01 and 1 micromol x L(-1), its inhibition rates were 7.03% and 22.72%, respectively. This compound possessed ideal vasorelaxant activity in vitro, and would be selected for further anti-hypertension evaluation in vivo. Moreover, by analyzing the primary activity and structure relationship of these compounds, it could be concluded that the SAR results of the reported phenylpiperazine alpha1-adrenoceptor antagonists could be used for reference in designing novel derivatives of naftopidil with optimal pharmacological properties.
Yao xue xue bao = Acta pharmaceutica Sinica 08/2007; 42(7):735-40.
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ABSTRACT: To study the metabolites of R, S-1-(2-methoxypheyl)-4-[3-(naphthal-yl-oxy)-2-hydroxypropyl] -piperazine, (naftopidil, NAF), a novel antihypertensive drug in rat plasma.
The rat plasma samples were analyzed by LC/MS after oral administration of NAF. According to MS relativity of metabolites and parent compound (NAF) and metabolic rule of compound with similar structure, the structure of potential metabolites were postulated. Phase I metabolites were identified by HPLC/MS and by comparison with authentic standards, phase II conjugates were indirectly identified with beta-D-glucuronidase in presence or absence of glucuronidase selective inhibitor D-saccharric acid beta-1,4-Lactone.
Phase I metabolites desmethyl-naftopidil (DMN), (phenyl) hydroxynaftopidil (PHN), (naphthyl) -hydroxy-naftopidil (NHN) were separated and identified in rat plasma by comparison with reference substances, phase II conjugates, NAF and NHN glucuronide conjugates were separated and tentatively identified by hydrolysis with glucuronidase, the aglycones, NAF and NHN, were identified in rat plasma.
The major metabolic pathway of NAF in rat plasma should be the hydroxylation of the phenyl or nephthyl moiety of NAF and demethylation of NAF. Therefore, (naphthyl) hydroxyl-metabolite and NAF followed by conjugation with beta-glueuronic acid.
Yao xue xue bao = Acta pharmaceutica Sinica 02/2006; 41(1):80-4.
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ABSTRACT: This paper reports a method based on liquid chromatography coupled with electrospray mass spectrometry for the analysis of terpenoids in ginkgo laminae.
The analysis was performed on ZORBAX RX-C18 (2.1 mm x 150 mm) column with methanol-water(with gradient) as mobile phase at a flow rate of 0.25 mL x min(-1), and column temperature of 25 degrees C. Analyses were carried out in the selected ion monitoring (SIM) mode.
Ginkgolides (GA, GB and GC) and bilobalide were quantitatively detected by external standardization with linear in the range of 4.04-1.012 x 10(2) ng, with coefficient and relative standard deviations being 0.993 7-0.999 8 and 2.50%-4.73%. LC-ESI-MS shows a greatly increased sensitivity compared with other methods. The detection limit of this method by SIM was 1.47 x 10(-3)-0.320 microg x mL(-1).
This method is specific, reproducible, rapidly and permits quantitative analyses of ginkgolides and bilobalide in different samples with simple pre-purification steps.
Zhongguo Zhong yao za zhi = Zhongguo zhongyao zazhi = China journal of Chinese materia medica 01/2006; 30(24):1915-8.
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ABSTRACT: Ten phenylpiperazine derivatives were designed and synthesized. The first complete assignments of (1)H and (13)C NMR chemical shifts for these phenylpiperazine derivatives were achieved by means of 1D and 2D NMR techniques, including (1)H-(1)H COSY, HSQC and HMBC spectra.
Magnetic Resonance in Chemistry 11/2005; 43(10):869-72. · 1.44 Impact Factor
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ABSTRACT: Computer aided drug discovery for selective antagonism effects on α1A subtypes of G-protein coupled receptors are important in the treatment of benign prostatic hyperplasia (BPH). Ligand-based pharmacophore models of N-Aryl and N-Heteroaryl piperazine α1A-antagonists were developed using two separate training sets. Pharmacophore models were generated using the flexible align method within the GALAHAD module, implemented in SYBYL8.1 software. The most significant pharmacophore hypothesis, characterized by the conflicting demands of maximizing pharmacophore consensus, maximizing steric consensus, and minimizing energy, consisted of one positive nitrogen center, one donor atom center, two acceptor atom centers, and two hydrophobic groups. The most active compound in each class training set showed a good fit with all features of the pharmacophore proposed. The resulting models also had something in common with the hypothesis using the Catalyst software reported in other publications. These α1A pharmacophore models could predict compounds well, both in the training set and the test set. The pharmacophore models were also validated by an external dataset using a portion of the ZINC database. A 3D-QSAR model using the pharmacophore model to align the compounds was established in this study. The CoMFA model with the cross-validated q2 value of 0.735 revealed that the model was valid. Our research provides a valuable tool for designing new therapeutic compounds with desired biological activity.
Journal of Molecular Graphics and Modelling.
