Q Meng

Dalian Medical University, Lü-ta-shih, Liaoning, China

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Publications (123)460.97 Total impact

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    ABSTRACT: In the development of atherosclerosis, naringin has exhibited potential protective effects. However, the specific mechanisms are not clearly understood. The aim of this trial was to determine the anti-oxidative and anti-inflammatory effects of naringin and uncover the mechanisms in Tumor Necrosis Factor-alpha (TNF-α) induced Human Umbilical Vein Endothelial Cells (HUVECs). Reactive Oxygen Species (ROS) were measured by flow cytometry assay. The levels of NADPH oxidase 4 (Nox4), p22phox, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) over-expressions were measured by qRT-PCR and Western blotting analyses. Activation of Phosphatidylinositol 3-kinase/Akt (PI3K/Akt) and Nuclear Factor-κB (NF-κB) was evaluated by Western blotting. Naringin inhibited ROS production as well as over-expression levels of Nox4, p22phox induced by TNF-α. Naringin inhibited TNF-α induced mRNA and protein over-expressions of ICAM-1 and VCAM-1. Naringin also suppressed activation of NF-κB and PI3K/Akt signaling pathways. These results indicated the preventive effects of naringin on HUVECs injury caused by oxidative stress and inflammation response and the effects might be obtained via inhibition of Nox4 and NF-κB pathways as well as activation of PI3K/Akt pathway. Naringin may be useful in preventing endothelial dysfunction, therefore to ameliorate the development of atherosclerosis.
    Current pharmaceutical biotechnology. 11/2014;
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    ABSTRACT: Liver resection has become a common treatment for liver tumors and hepatocellular carcinoma over the past decades. However, after surgery, the remnant livers in some patients fail to regenerate. Therefore, there is an urgent medical need to develop drugs that can promote liver regeneration. The purpose of the current study is to investigate the promotive effect of alisol B 23-acetate (AB23A) on liver regeneration in mice following partial hepatectomy (PH), and further elucidate the involvement of farnesoid X receptor (FXR) in the liver regeneration-promotive effect using in vivo and in vitro experiments. The results showed that AB23A dose-dependently promoted hepatocyte proliferation via upregulating hepatocyte proliferation-related protein forkhead box M1b (FoxM1b), Cyclin D1 and Cyclin B1 expression, and attenuated liver injury via an inhibition in Cyp7a1 and an induction in efflux transporters Bsep expression resulting in reduced hepatic bile acid levels. These changes in the genes, as well as accelerated liver regeneration in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly showed the regulation of these genes by AB23A was abrogated when FXR was silenced. Luciferase reporter assay in HepG2 cells and molecular docking further demonstrated the effect of AB23A on FXR activation in vitro. In conclusions, AB23A produces promotive effect on liver regeneration, due to FXR-mediated regulation of genes involved in hepatocyte proliferation and hepato-protection. AB23A has the potential to be a novel therapeutic option for facilitating efficient liver regeneration in patients subjected to liver resection.
    Biochemical pharmacology. 09/2014;
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    ABSTRACT: Investigating the hepatoprotective effect of calycosin against acute liver injury in association with FXR activation and STAT3 phosphorylation.
    Pharmaceutical research. 08/2014;
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    ABSTRACT: The purpose of the present study was to elucidate the transporter-mediated pharmacokinetics mechanism of drug-drug interactions (DDI) between bestatin and cefixime. The plasma concentrations and bioavailabilities of bestatin and cefixime were decreased after oral co-administration in rats. The uptake in rat everted intestinal sacs of bestatin and cefixime were dramatically declined after co-administration of the two drugs. Bestatin and cefixime can mutually competitively inhibit the uptake by hPEPT1-HeLa cells. The plasma concentrations of bestatin and cefixime were increased; however, the cumulative biliary excretion had no significant change, and the cumulative urinary excretion and renal clearance of the two drugs in rats decreased after intravenous coadministration. Moreover, decreased uptake of the two drugs was observed in human kidney slices, rat kidney slices and hOAT1/hOAT3-transfected HEK293 cells when bestatin and cefixime were coadministered. The accumulation of bestatin and cefixime in kidney slices can be inhibited by p-aminohippuate, benzylpenicillin and probencid, but not by tetraethyl ammonium. The results suggest that intestinal absorption and renal excretion of bestatin and cefixime can be inhibited when the two drugs were co-administered in rats. The pharmacokinetic mechanism indicates that the DDIs between bestatin and cefixime are mainly mediated by Pept1 and Oat1/3 in rats. PEPT1 and OAT1/3 are the target transporters of DDIs between bestatin and cefixime in human kidney slices and human transfected cells, proposing possible drug-drug interaction in humans.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 07/2014; · 2.61 Impact Factor
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    ABSTRACT: A simple and rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of JBP485, Gly-Sar and JBP923 in the cell lysates using methanol as a deproteinization solvent was developed and validated. Detection was performed by turbo ionspray ionization in multiple reaction monitoring mode using the transitions of m/z 147.1 → m/z 90.1 for Gly-Sar, m/z 201.1 → m/z 86.1 for JBP485, m/z 219.1 → m/z 86.1 for JBP923 and m/z 152.0 → m/z 110.0 for paracetamol (internal standard). The analytes were separated on a Hypersil ODS C18 HPLC column using isocratic elution mode with a mobile phase containing 0.1% formic acid in water-methanol (97:3, v/v) at a flow rate of 0.2 mL/min. The calibration curves were demonstrated to be linear over the concentration range of 5.00-5000 nm with coefficient of 0.9968 for Gly-Sar, 0.9975 for JBP485 and 0.9952 for JBP923. The intra- and inter-day precisions were <10.2% for each quality contro; level, and the accuracy was within ±5.6% for each analyte. The matrix effect, the extraction recovery and stabilities of LC-MS/MS analysis were also investigated. This validated method was successfully applied to the simultaneous determination of JBP485, Gly-Sar and JBP923 in the cell lysates for identification of stably transfected HeLa cells with human PEPT1. Copyright © 2014 John Wiley & Sons, Ltd.
    Biomedical Chromatography 06/2014; · 1.95 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate transporter-mediated renal excretion mechanism for cilostazol and to characterize the mechanism of drug-drug interaction (DDI) between cilostazol and aspirin or probenecid. Concentrations of cilostazol and its metabolites (OPC-13015 and OPC-13213) in rat biological or cell samples were measured by LC-MS/MS. Co-administration with probenecid, benzylpenicillin or aspirin decreased cilostazol cumulative urinary excretion and renal clearance. Concentrations of cilostazol and OPC-13213 in plasma were decreased and OPC-13015 concentration was increased in presence of probenecid, whereas, in combination with benzylpenicillin or aspirin, rat plasma cilostazol sharply increased and concentrations of OPC-13015 and OPC-13213 did not change. In urine, OPC-13015 was below the level of detection. Cumulative urinary excretion of OPC-13213 decreased in presence of probenecid, benzylpenicillin or aspirin. Cilostazol was distributed in kidney and liver with Kp values of 8.4 mL/g and 16.3 mL/g. Probenecid and aspirin reduced cilostazol distribution in kidney. Probenecid did not affect cilostazol metabolism in kidney, but increased cilostazol metabolism in liver, and aspirin had no effect on cilostazol metabolism. Benzylpenicillin, aspirin and JBP485 reduced cilostazol uptake in kidney slices and hOAT3-HEK293 cells, while -aminohippuric acid did not. Compared to vector, hOAT3-HEK293 cells accumulated more cilostazol whereas hOAT1-HEK293 cells did not. OAT3 and Oat3 play the major role in cilostazol renal excretion, while OAT1 and Oat1 do not. Oat3 and Cyp3a are both targets of DDI between cilostazol and probenecid. Aspirin inhibits OAT3-mediated uptake of cilostazol and does not influence cilostazol metabolism.
    Drug metabolism and disposition: the biological fate of chemicals 04/2014; · 3.74 Impact Factor
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    ABSTRACT: Eprosartan is an angiotensin II receptor antagonist, used in the treatment of hypertension and heart failure in clinical patients. The objective of this study was to clarify the mechanism underlying hepatic uptake and biliary excretion of eprosartan in rats and humans.
    Pharmacological reports: PR 04/2014; 66(2):311-319. · 1.97 Impact Factor
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    ABSTRACT: The purpose of this study was to investigate the enhancing effect of dioscin on the absorption of methotrexate (MTX) and clarify the molecular mechanism involved in vivo and in vitro. Dioscin increased MTX chemosensitivity and transepithelial flux in the absorptive direction, significantly inhibiting multidrug resistance 1 (MDR1) mRNA and protein expression and MDR1 promoter and nuclear factor κ-B (NF-κB) activity in Caco-2 cells. Moreover, inhibitor κB-α (IκB-α) degradation was inhibited by dioscin. Dioscin enhanced the intracellular concentration of MTX by down-regulating MDR1 expression through a mechanism that involves NF-κB signaling pathway inhibition in Caco-2 cells. Dioscin strengthened MTX absorption by inhibiting MDR1 expression in rat intestine. In addition, even though MTX is absorbed into the enterocytes, there was no increase in toxicity observed, and that, in fact, decreased toxicity was seen.
    Toxicology and Applied Pharmacology 03/2014; · 3.98 Impact Factor
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    ABSTRACT: Aim: Inflammation and oxidative stress are now recognized to be two important contributing factors to the development of atherosclerosis(AS). NADPH oxidase-4 (Nox4)-derived reactive oxygen species(ROS), NF-κB and MAPK play crucial roles in these processes. Luteolin, a flavone rich in many plants, can interrupt the molecular expression and inhibit the progression of inflammation and oxidative stress. The present study was designed to test whether luteolin inhibits TNF-α-induced inflammation and oxidative stress in human umbilical vein endothelial cells(HUVECs) and identify some of the mechanisms underlying these effects. Methods: HUVECs were treated with luteolin in the presence/absence of TNF-α. The mechanism of luteolin against TNF-α-induced cell injury was evaluated using Western blotting, real-time RT-PCR and flow cytometry analyses. Results: Luteolin suppressed the TNF-α-activated ROS generation, as well as the Nox4, p22phox, and ICAM-1 and VCAM-1 expression. Luteolin also enhanced the Bcl-2 and reduced caspase-3, -9 expression in the TNF-α-treated HUVECs. Finally, luteolin inhibited the TNF-α-induced transcriptional activity of NF-κB and p38 in addition to ERK1/2 phosphorylation. The inhibitors and siRNA of Nox4 and NF-κB not only reduced ROS generation, p38, ERK1/2 phosphorylation and the ICAM-1 and VCAM-1 expression, but also enhanced Bcl-2 expression. The inhibitor of p38 had the same effect on the expression of ICAM-1, VCAM-1 and Bcl-2, while the inhibitor of ERK1/2 increased the Bcl-2 expression rather than reducing the ICAM-1 and VCAM-1 expression. Conclusions: Luteolin attenuates TNF-α-induced oxidative stress and inflammation via its effects on the Nox4/ROS-NF-κB and MAPK pathways. These results suggest that luteolin may provide a beneficial effect in treating vascular diseases associated with oxidative stress and inflammation.
    Journal of atherosclerosis and thrombosis 03/2014; · 2.93 Impact Factor
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    ABSTRACT: To clarify the pharmacokinetic interaction and its possible mechanism, mutual effects between methotrexate (MTX) and bestatin in oral absorption and renal excretion in rats were examined in vivo and in vitro. A sensitive, quick and high performance method (LC-MS/MS) was used to determine concentrations of MTX and bestatin in biological samples. Plasma concentrations of MTX and bestatin markedly increased following oral and intravenous administration of MTX in combination with bestatin. The cumulative urinary excretion and renal clearance of the two drugs significantly decreased when MTX and bestatin were co-administered intravenously. Uptake of the two drugs in in situ single-pass intestinal perfusion studies and in vitro everted intestinal sac preparations significantly increased when co-administered, while uptake in rat kidney slices and hOAT1- or hOAT3-HEK 293 cells significantly decreased. Transport rates of bestatin and MTX from basolateral-to-apical transepithelial transport in MDR1-MDCK cells significantly decreased following co-administration. Additionally, intracellular concentrations increased, and the efflux transport of the two drugs was inhibited when given together. The IC50 values of MTX and bestatin in K562 and K562/ADR cells decreased when the two were co-administered. These findings indicate that the pharmacokinetic mechanism of interaction between MTX and bestatin occurs through co-transport by P-gp in the intestinal mucosa and OATs within the kidneys.
    International Journal of Pharmaceutics 02/2014; · 3.99 Impact Factor
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    ABSTRACT: Efflux of monocaroxylates like lactate, pyruvate, and ketone bodies from astrocytes through monocarboxylate transporter 4 (MCT4) supplies the local neuron population with metabolic intermediates to meet energy requirements under conditions of increased demand. Disruption of this astroglial-neuron metabolic coupling pathway may contribute to epileptogenesis. We measured MCT4 expression in temporal lobe epileptic foci excised from patients with intractable epilepsy and in rats injected with pilocarpine, an animal model of temporal lobe epilepsy (TLE). Cortical MCT4 expression levels were significantly lower in TLE patients compared with controls, due at least partially to MCT4 promoter methylation. Expression of MCT4 also decreased progressively in pilocarpine-treated rats from 12 h to 14 days post-administration. Underexpression of MCT4 in cultured astrocytes induced by a short hairpin RNA promoted apoptosis. Knockdown of astrocyte MCT4 also suppressed excitatory amino acid transporter 1 (EAAT1) expression. Reduced MCT4 and EAAT1 expression by astrocytes may lead to neuronal hyperexcitability and epileptogenesis in the temporal lobe by reducing the supply of metabolic intermediates and by allowing accumulation of extracellular glutamate.
    Molecular Neurobiology 01/2014; · 5.47 Impact Factor
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    ABSTRACT: Peptidomimetic drugs have favorable bioavailability owing to H(+) /peptide transporter 1 (PEPT1) located in the intestine. Sartans are commonly used and likely coadministered with peptidomimetic drugs in the clinic; however, in vivo interactions between sartans and peptidomimetic drugs have not been systemically understood. Herein, the effect and mechanism of sartans on the intestinal absorption and renal excretion of the dipeptide-like drug bestatin were investigated. Following oral combination with valsartan, the plasma concentration and area under the plasma concentration-time curve of bestatin in rats decreased significantly. Bestatin absorption in rat-everted intestinal sacs was dramatically reduced by valsartan. Sartans exhibited concentration-dependent inhibition on the uptake of bestatin in human PEPT1 (hPEPT1)-HeLa cells. The cumulative urinary excretion and renal clearance of the two drugs in rats decreased after intravenous coadministration. Moreover, decreased uptake of the two drugs was observed in rats' kidney slices and human organic anion transporter (hOAT)1/hOAT3-transfected cells when coadministered. The results suggest that the intestinal absorption and renal excretion of bestatin in rats were inhibited by coadministered valsartan. Interestingly, the half-maximal inhibitory concentration (IC50) values of valsartan for PEPT1 and OAT1/3 were comparable to the theoretically estimated local drug concentration and the clinical unbound concentration, respectively, proposing possible drug-drug interaction in humans via PEPT1 and OAT1/3, which should be paid particular attention when bestatin and valsartan are coadministrated clinically. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci.
    Journal of Pharmaceutical Sciences 12/2013; · 3.13 Impact Factor
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    ABSTRACT: To conduct in vivo and in vitro experiments to investigate puerarin (PUR), an isoflavone C-glyoside, and elucidate its ability to alter methotrexate (MTX) transport and pharmacokinetics. In vivo absorption studies, in vitro everted intestinal sac preparation, kidney slices in rats and bi-directional transport assay with mock-/MDCK-MDR1 cells, uptake studies in HEK293-OAT1/3 cells were employed to evaluate the interaction. In vivo and in vitro MTX absorption in rats were enhanced in combination with PUR. PUR inhibited digoxin efflux transport in MDCK-MDR1 monolayers with an IC50 value of 1.6 ± 0.3 μM, suggesting that the first target of drug interaction was MDR1 in the intestine during the absorption process. MTX renal clearance decreased significantly after simultaneous intravenous administration. MTX uptake in rat kidney slices and HEK293-OAT1/3 cells were markedly inhibited by PUR, suggesting that the second target of drug interaction was OATs located in the kidney. Moreover, concomitant administration of PUR reduced renal MTX accumulation and plasma levels of creatinine and BUN. Co-administration of PUR enhanced MTX exposure by inhibition of intestinal MDR1 and renal OAT1/3. Although the renal damage of MTX was improved by PUR, the high level exposure of MTX should be cautious in the clinical usage.
    Pharmaceutical Research 11/2013; · 4.74 Impact Factor
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    ABSTRACT: We investigated whether entecavir is a substrate of the oligopeptide transporter 2 (PEPT2) and whether reabsorption of entecavir is mediated by PEPT2 as well as what is the contribution of PEPT2 to entecavir reabsorption during urinary excretion. Entecavir uptake in transfected cells and rat kidney slices, changes in urine entecavir concentrations following isolated kidney perfusion and in vivo entecavir plasma and urine concentrations were determined with LC-MS/MS. In hPEPT2-HELA cells, entecavir uptake was significantly higher compared to vector-HELA cells and was sharply inhibited by Gly-sar and JBP485, and there were two distinct transport systems. The Km and Vmax of entecavir were 427 (μM) and 1.60 (nmol/mg protein/30s) (low-affinity, high-velocity system) and 24.0 (μM) and 0.296 (nmol/mg protein/30s) (high-affinity, low-velocity system). In rat kidney slices, uptake of entecavir was not markedly inhibited by Gly-sar. In isolated kidney perfusion experiments, entecavir cumulative urinary excretion was statistically significant at 45 and 60 min. CLR(4°C), CLR(37°C Control) and CLR(37°C Expriment) were 12.6, 27.6 and 36 (ml/min/kg), respectively. CLTS and TR rate (for PEPT2) were 25.3 and 9.4 (ml/min/kg). In vivo, the cumulative urinary excretion of entecavir had statistical significance at 3 and 4 h with CLR(Control) and CLR(Expriment) values of 31 and 42 (ml/min/kg), respectively. The CLTS and TR rate (for PEPT2) were 32 and 11.6 (ml/min/kg), respectively. The present study demonstrated that entecavir is a substrate of PEPT2. Moreover, reabsorption of entecavir is mediated by PEPT2, and 25% of urinary entecavir is reabsorbed by PEPT2.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 10/2013; · 2.61 Impact Factor
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    ABSTRACT: Bestatin is an immunomodulator with antitumor activity. This study was performed to investigate the effect of P-gp on the intestinal absorption and antiproliferative activity of bestatin. Our results showed that P-gp inhibitors significantly increased rat intestinal absorption of bestatin in vivo and in vitro. The net efflux ratio of bestatin was 2.2 across mock-/MDR1-MDCK cell monolayers and was decreased by P-gp inhibitors, indicating bestatin was a substrate of P-gp. Furthermore, the IC50 values of bestatin on U937 and K562 cells were decreased dramatically and the intracellular concentrations of bestatin were increased by incubation of cells with verapamil or cyclosporin A. K562/ADR cells exhibited a higher IC50 value and a lower intracellular level of bestatin. The bestatin level in K562/ADR cells was partially restored by incubation with doxorubicin. However, P-gp and APN mRNA levels were not changed by bestatin. These results suggested that the intestinal absorption and accumulation in cancer cells for bestatin were limited by P-gp-mediated efflux. Additional attention should be paid to the alternative exposure of bestatin when bestatin was coadministered with drugs as P-gp substrates in clinic.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 08/2013; · 2.61 Impact Factor
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    ABSTRACT: We investigated the effects of JBP485 (an anti-inflammatory dipeptide and a substrate of OAT) on regulation of the expression and function of renal Oat1 and Oat3, which can accelerate the excretion of accumulated uremic toxins (e.g. indoxyl sulfate) in the kidney to improve gentamicin-induced ARF in rats. JBP485 caused a significant decrease in the accumulation of endogenous substances (creatinine, blood urea nitrogen and indoxyl sulfate) in vivo, an increase in the excretion of exogenous compounds (lisinopril and inulin) into urine, and up-regulation of the expressions of renal Oat1 and Oat3 in the kidney tissues and slices via substrate induction. To determine the effect of JBP485 on the accelerated excretion of uremic toxins mediated by Oat1 and Oat3, the mRNA and protein expression levels of renal basolateral Oats were assessed by quantitative real-time PCR, western blot, immunohistochemical analysis and an immunofluorescence method. Gentamicin down-regulated the expression of Oats mRNA and protein in rat kidney, and these effects were reversed after administration of JBP485. In addition, JBP485 caused a significant decrease in MPO and MDA levels in the kidney, and improved the pathological condition of rat kidney. These results indicated that JBP485 improved acute renal failure by increasing the expression and function of Oat1 and Oat3, and by decreasing overoxidation of the kidney in gentamicin-induced ARF rats.
    Toxicology and Applied Pharmacology 05/2013; · 3.98 Impact Factor
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    ABSTRACT: The purpose of this study was to investigate the ameliorating effect of dioscin (1) on multidrug resistance (MDR) in adriamycin (ADR)-resistant erythroleukemic cells (K562/adriamycin, K562/ADR) and to clarify the molecular mechanisms involved. High levels of multidrug resistance 1 (MDR1) mRNA and protein and reduced ADR retention were found in K562/ADR cells compared with parental cells (K562). Dioscin (1), a constituent of plants in the genus Discorea, significantly inhibited MDR1 mRNA and protein expression and MDR1 promoter and nuclear factor κ-B (NF-κB) activity in K562/ADR cells. MDR1 mRNA and protein suppression resulted in the subsequent recovery of intracellular drug accumulation. Additionally, inhibitor κB-α (IκB-α) degradation was inhibited by 1. Dioscin (1) reversed ADR-induced MDR by down-regulating MDR1 expression by a mechanism that involves the inhibition of the NF-κB signaling pathway. These findings provide evidence to support the further investigation of the clinical application of dioscin (1) as a chemotherapy adjuvant.
    Journal of Natural Products 04/2013; · 3.29 Impact Factor
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    ABSTRACT: Background: Acyclovir is acyclic guanosine derivative. Benzylpenicillin (PCG) is a β-lactam antibiotic. The purpose of this study was to investigate the pharmacokinetic drug-drug interaction (DDI) between PCG and acyclovir. Method: When acyclovir and PCG were co-administered, plasma concentration of acyclovir, urinary excretion of acyclovir in vivo, uptake of acyclovir in kidney slices and uptake of acyclovir in human (h) OAT1/hOAT3- HEK293 cells were determined to examine the effect of PCG on urinary excretion of acyclovir. Results: The plasma concentration of acyclovir was increased markedly and accumulative renal excretion and renal clearance of acyclovir were decreased significantly after intravenous administration of acyclovir in combination with PCG. PCG could decrease the uptake of acyclovir in kidney slices and in hOAT1-/hOAT3-human embryonic kidney (HEK293) cells. Conclusions: It indicates that acyclovir is a substrate for OAT1 and OAT3. PCG inhibits the renal excretion of acyclovir by inhibiting renal transporters OAT1 and OAT3 in vivo and in vitro. These results suggest important information for DDI between PCG and acyclovir in kidney.
    Pharmacological reports: PR 03/2013; 65(2):505-12. · 1.97 Impact Factor
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    ABSTRACT: The objective of this study was to clarify the mechanism underlying hepatic uptake of dioscin, a herbal ingredient with anti-hepatitis activity, in rat and human. The liver uptake index (LUI) in vivo, perfused rat liver in situ, rat liver slices, isolated rat hepatocytes and human organic anion-transporting polypeptide (OATP)-transfected cells in vitro were used to evaluate hepatic uptake of dioscin. Values of 11.9 ± 1.6% and 15.0 ± 0.9% of dose for uptake of dioscin were observed by LUI in vivo and perfused rat livers in situ, respectively. The time course of dioscin uptake by rat liver slices was temperature-dependent. Uptake of dioscin by rat liver slices and isolated rat hepatocytes was inhibited significantly by Oatp modulators, such as ibuprofen (Oatp1a1 inhibitor), digoxin (Oatp1a4 substrate) and glycyrrhizic acid (Oatp1b2 inhibitor), but not by tetraethyl ammonium (TEA) or p-aminohippurate (PAH). Uptake of dioscin in rat hepatocytes and OATP1B3-human embryonic kidney cells (HEK) 293 cells indicated a saturable process with K(m) of 3.75 ± 0.51 μM and 2.08 ± 0.27 μM, respectively. (-)-Epigallocatechin gallate (EGCG), cyclosporin A, rifampicin and telmisartan inhibited transport of dioscin in OATP1B3-HEK293 cells. However, transcellular transport of dioscin in OATP1B1- or OATP1B1/MRP2-Madin-Darby canine kidney strain (MDCK) II cells was not observed. These results indicate that hepatic uptake of dioscin is involved in OATP1B3 in human, and multiple Oatps might participate in this process in rat.
    Drug metabolism and disposition: the biological fate of chemicals 02/2013; · 3.74 Impact Factor
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    ABSTRACT: Entecavir and JBP485 (a dipeptide) exhibit the antihepatitis activities and it is possible for the two drugs to be coadministered in the treatment of hepatitis. We aimed to elucidate whether entecavir was a substrate of OAT1, OAT3, OCT, and PEPT1 and to investigate the targets of drug-drug interactions between entecavir and JBP485. Plasma and urine concentrations of entecavir following intravenous and oral administration in vivo, uptake of entecavir in kidney slices and transfected cells in vitro, were determined by LC-MS/MS. Following intravenous co-administration of entecavir and JBP485 in rats, entecavir AUC increased 1.93-fold, t (1/2β) was prolonged 2.08-fold, CL(P) decreased 49%, CL(R) decreased 73%, and accumulated urinary excretion decreased 54%. However, following oral co-administration, the entecavir T(max) and C(max) were not affected; the degree of change in other pharmacokinetic parameters (AUC, t(1/2β), CL(P), and accumulated urinary excretion) was similar to that of intravenous administration. The uptake of entecavir was nearly identical in hPEPT1- as in vector-HELA cells. In rat kidney slices, uptake of entecavir was markedly inhibited by p-aminohippurate, benzylpenicillin, JBP485, and tetraethyl ammonium. In hOAT1- and hOAT3-HEK293 cells, uptake of entecavir was significantly higher compared to vector-HEK293 cells and was markedly inhibited by p-aminohippurate, benzylpenicillin, and JBP485. Km and Vmax values of entecavir were 250 μM and 0.83 nmol/mg protein/30s (OAT1) and 23 μM and 1.1 nmol/mg protein/30s (OAT3), respectively. Entecavir is the substrate of OAT1, OAT3, and OCT. Moreover, OAT1 and OAT3 are the targets of DDI between entecavir and JBP485.
    European journal of pharmaceutical sciences: official journal of the European Federation for Pharmaceutical Sciences 01/2013; · 2.61 Impact Factor

Publication Stats

3k Citations
460.97 Total Impact Points

Institutions

  • 2010–2014
    • Dalian Medical University
      • College of Pharmacy
      Lü-ta-shih, Liaoning, China
  • 2012
    • Capital Medical University
      • Department of Immunology
      Peping, Beijing, China
  • 2009–2012
    • King's College London
      • MRC and Asthma UK Centre in Allergic Mechanisms of Asthma
      Londinium, England, United Kingdom
  • 2001–2003
    • Imperial College London
      • Section of Allergy and Clinical Immunology
      London, ENG, United Kingdom
  • 1991–2001
    • National Heart, Lung, and Blood Institute
      Maryland, United States
  • 1995–1997
    • The Heart Lung Center
      Londinium, England, United Kingdom
  • 1993–1996
    • The British Society for Allergy & Clinical Immunology
      Londinium, England, United Kingdom