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Kim L. R. Brouwer - One of the best experts on this subject based on the ideXlab platform.

  • endogenous coproporphyrin i and iii are altered in multidrug resistance associated protein 2 deficient tr rats
    Journal of Pharmaceutical Sciences, 2021
    Co-Authors: Jacqueline Bezencon, James J Beaudoin, Chitra Saran, Janine Hussner, Yueping Zhang, Hong Shen, John K Fallon, Philip C Smith, Henriette Meyer Zu E Schwabedissen, Kim L. R. Brouwer
    Abstract:

    Recent studies have focused on coproporphyrin (CP)-I and CP-III (CPs) as endogenous biomarkers for organic anion transporting polypeptides (OATPs). Previous data showed that CPs are also substrates of multidrug resistance-associated protein (MRP/Mrp) 2 and 3. This study was designed to examine the impact of loss of Mrp2 function on the routes of excretion of endogenous CPs in wild-type (WT) Wistar compared to Mrp2-deficient TR- rats. To exclude possible confounding effects of rat Oatps, the transport of CPs was investigated in Oatp-overexpressing HeLa cells. Results indicated that CPs are substrates of rodent Oatp1b2, and that CP-III is a substrate of Oatp2b1. Quantitative targeted absolute proteomic (QTAP) analysis revealed no differences in Oatps, but an expected significant increase in Mrp3 protein levels in TR- compared to WT rat livers. CP-I and CP-III concentrations measured by LC-MS/MS were elevated in TR- compared to WT rat liver, while CP-I and CP-III estimated Biliary Clearance was decreased 75- and 840-fold in TR- compared to WT rats, respectively. CP-III concentrations were decreased 14-fold in the feces of TR- compared to WT rats, but differences in CP-I were not significant. In summary, the disposition of CPs was markedly altered by loss of Mrp2 and increased Mrp3 function as measured in TR- rats.

  • altered hepatoBiliary disposition of tolvaptan and selected tolvaptan metabolites in a rodent model of polycystic kidney disease
    Drug Metabolism and Disposition, 2019
    Co-Authors: James J Beaudoin, William J. Brock, Jacqueline Bezencon, Yanguang Cao, Katsuhiko Mizuno, Sharin E Roth, Kim L. R. Brouwer
    Abstract:

    Tolvaptan, a vasopressin V2-receptor antagonist, has demonstrated efficacy in slowing kidney function decline in patients with autosomal dominant polycystic kidney disease (ADPKD). In the pivotal clinical trial, the incidence of elevated liver enzymes was higher in patients receiving tolvaptan compared with placebo. Adjudication by a panel of expert hepatologists concluded a causal link of tolvaptan to liver injury in patients with ADPKD. An ex situ isolated perfused liver (IPL) study of tolvaptan disposition was undertaken in a rodent model of ADPKD, the polycystic kidney (PCK) rat (n = 5), and compared with wild-type (WT) Sprague-Dawley rats (n = 6). Livers were perfused with tolvaptan, followed by a tolvaptan-free washout phase. Total recovery (mean ± S.D. percentage of dose; PCK vs. WT) of tolvaptan and two metabolites, DM-4103 and DM-4107, quantified by liquid chromatography-tandem mass spectroscopy, was 58.14% ± 24.72% vs. 43.40% ± 18.11% in liver, 20.10% ± 9.15% vs. 21.17% ± 12.51% in outflow perfusate, and 0.08% ± 0.01% vs. 0.39% ± 0.32% in bile. DM-4103 recovery (mean ± S.D. percentage of dose) was decreased in PCK vs. WT bile (<0.01% ± <0.01% vs. 0.02% ± 0.01%; P = 0.0037), and DM-4107 recovery was increased in PCK vs. WT outflow perfusate (1.60% ± 0.57% vs. 0.43% ± 0.29%; P = 0.0017). A pharmacokinetic compartmental model assuming first-order processes was developed to describe the rate vs. time profiles of tolvaptan and DM-4103 + DM-4107 in rat IPLs. The model-derived estimate of tolvaptan's Biliary Clearance was significantly decreased in PCK compared with WT IPLs. The model predicted greater hepatocellular concentrations of tolvaptan and DM-4103 + DM-4107 in PCK compared with WT IPLs. Increased hepatocellular exposure to tolvaptan and metabolites may contribute to the hepatotoxicity in patients with ADPKD treated with tolvaptan.

  • farnesoid x receptor agonists obeticholic acid and chenodeoxycholic acid increase bile acid efflux in sandwich cultured human hepatocytes functional evidence and mechanisms
    Journal of Pharmacology and Experimental Therapeutics, 2018
    Co-Authors: Carl Lacerte, Kenneth R Brouwer, Jeffrey E Edwards, Kim L. R. Brouwer
    Abstract:

    The farnesoid X receptor (FXR) is a nuclear receptor that regulates genes involved in bile acid homeostasis. FXR agonists, obeticholic acid (OCA) and chenodeoxycholic acid (CDCA), increase mRNA expression of efflux transporters in sandwich-cultured human hepatocytes (SCHH). This study evaluated the effects of OCA and CDCA treatment on the uptake, basolateral efflux, and Biliary excretion of a model bile acid, taurocholate (TCA), in SCHH. In addition, changes in the protein expression of TCA uptake and efflux transporters were investigated. SCHH were treated with 1 µM OCA, 100 µM CDCA, or vehicle control for 72 hours followed by quantification of deuterated TCA uptake and efflux over time in Ca2+-containing and Ca2+-free conditions (n = 3 donors). A mechanistic pharmacokinetic model was fit to the TCA mass-time data to obtain estimates for total uptake Clearance (CLUptake), total intrinsic basolateral efflux Clearance (CLint,BL), and total intrinsic Biliary Clearance (CLint,Bile). Modeling results revealed that FXR agonists significantly increased CLint,BL by >6-fold and significantly increased CLint,Bile by 2-fold, with minimal effect on CLUptake. Immunoblotting showed that protein levels of the basolateral transporter subunits organic solute transporter α and β (OSTα and OSTβ) in FXR agonist-treated SCHH were significantly induced by >2.5- and 10-fold, respectively. FXR agonist-mediated changes in the expression of other TCA transporters in SCHH were modest. In conclusion, this is the first report demonstrating that OCA and CDCA increased TCA efflux in SCHH, which contributed to reduced intracellular TCA concentrations. Increased basolateral efflux of TCA was consistent with increased OSTα/β protein expression in OCA- and CDCA-treated SCHH.

  • inhibition of human hepatic bile acid transporters by tolvaptan and metabolites contributing factors to drug induced liver injury
    Toxicological Sciences, 2016
    Co-Authors: Jason R. Slizgi, Robert L. St. Claire, Kimberly M. Freeman, William J. Brock, Kenneth R Brouwer, Maxwell Pan, Kim L. R. Brouwer
    Abstract:

    Tolvaptan is a vasopressin V(2)-receptor antagonist that has shown promise in treating Autosomal Dominant Polycystic Kidney Disease (ADPKD). Tolvaptan was, however, associated with liver injury in some ADPKD patients. Inhibition of bile acid transporters may be contributing factors to drug-induced liver injury. In this study, the ability of tolvaptan and two metabolites, DM-4103 and DM-4107, to inhibit human hepatic transporters (NTCP, BSEP, MRP2, MRP3, and MRP4) and bile acid transport in sandwich-cultured human hepatocytes (SCHH) was explored. IC(50) values were determined for tolvaptan, DM-4103 and DM-4107 inhibition of NTCP (∼41.5, 16.3, and 95.6 μM, respectively), BSEP (31.6, 4.15, and 119 μM, respectively), MRP2 (>50, ∼51.0, and >200 μM, respectively), MRP3 (>50, ∼44.6, and 61.2 μM, respectively), and MRP4 (>50, 4.26, and 37.9 μM, respectively). At the therapeutic dose of tolvaptan (90 mg), DM-4103 exhibited a C(max)/IC(50) value >0.1 for NTCP, BSEP, MRP2, MRP3, and MRP4. Tolvaptan accumulation in SCHH was extensive and not sodium-dependent; intracellular concentrations were ∼500 μM after a 10-min incubation duration with tolvaptan (15 μM). The Biliary Clearance of taurocholic acid (TCA) decreased by 43% when SCHH were co-incubated with tolvaptan (15 μM) and TCA (2.5 μM). When tolvaptan (15 μM) was co-incubated with 2.5 μM of chenodeoxycholic acid, taurochenodeoxycholic acid, or glycochenodeoxycholic acid in separate studies, the cellular accumulation of these bile acids increased by 1.30-, 1.68-, and 2.16-fold, respectively. Based on these data, inhibition of hepatic bile acid transport may be one of the biological mechanisms underlying tolvaptan-associated liver injury in patients with ADPKD.

  • identification of hepatic phospholipidosis inducers in sandwich cultured rat hepatocytes a physiologically relevant model reveals altered basolateral uptake and Biliary excretion of anionic probe substrates
    Toxicological Sciences, 2014
    Co-Authors: Brian C Ferslew, Kim L. R. Brouwer
    Abstract:

    Drug-induced phospholipidosis (PLD) is characterized by phospholipid accumulation within the lysosomes of affected tissues, resulting in lysosomal enlargement and laminar body inclusions. Numerous adverse effects and toxicities have been linked to PLD-inducing drugs, but it remains unknown whether drug-induced PLD represents a distinct toxicity or cellular adaptation. In silico and immortalized cellular models have been used to evaluate the PLD potential of new drugs, but these systems have some limitations. The aims of this study were to determine whether primary sandwich-cultured hepatocytes (SCH) can serve as a sensitive and selective model to evaluate hepatic drug-induced PLD, and to evaluate the impact of PLD on the uptake and Biliary excretion of probe substrates, taurocholate (TC) and rosuvastatin (RSV). Rat SCH were cultured for 48 h with prototypic hepatic PLD-inducing drugs, amiodarone (AMD), chloroquine (CHQ), desipramine (DES), and azithromycin (AZI), as well as the renal PLD inducer gentamicin (GTM). LysoTracker Red localization and transmission electron microscopy indicated enlarged lysosomal compartments and laminar body inclusions in SCH treated with AMD, CHQ, DES, and AZI, but not GTM, relative to control. PLD resulted in a 51–92% decrease in the in vitro Biliary Clearance of both TC and RSV; the Biliary excretion index significantly decreased for TC from 88 to 35–73%. These data suggested that PLD significantly reduced both organic anion transporting polypeptide-mediated uptake, and bile salt export pump-mediated Biliary transport processes. The current study demonstrates that the rat SCH system is a promising model to study hepatic PLD in vitro. Altered hepatic transport of anionic substrates secondary to drug-induced PLD is a novel finding.

Yuichi Sugiyama - One of the best experts on this subject based on the ideXlab platform.

  • organic anion transporting polypeptide 1a4 is responsible for the hepatic uptake of cardiac glycosides in mice
    Drug Metabolism and Disposition, 2018
    Co-Authors: Junichi Takano, Kazuya Maeda, Hiroyuki Kusuhara, Yuichi Sugiyama
    Abstract:

    Among organic anion transporting polypeptide (Oatp) family transporters expressed in the rodent liver, such as Oatp1a1, Oatp1a4, Oatp1b2, and Oatp2b1, Oatp1a4 has a unique character to recognize neutral cardiac glycosides as a substrate in addition to organic anions. The relative contribution of Oatp1a4 to the substrate uptake into hepatocytes has not been clarified. In this study, we investigated the importance of Oatp1a4 in the hepatic uptake of its substrate drugs using Slco1a4−/− mice. The hepatic mRNA expression of Slco1a4 was decreased significantly in Slco1a4−/− mice, whereas no differences were seen in other hepatic transporters between wild-type and Slco1a4−/− mice. We determined the plasma concentrations and liver-to-plasma concentration ratios (Kp,liver) of Oatp1a4 substrates, including ouabain, digoxin, BQ-123, fexofenadine, rosuvastatin, pravastatin, nafcillin, and telmisartan, after continuous intravenous infusion. The plasma concentrations of ouabain and rosuvastatin were 2.1-fold and 1.7-fold higher in Slco1a4−/− mice, and Kp,liver of ouabain and digoxin were 13.4-fold and 4.3-fold lower in Slco1a4−/− mice, respectively. Furthermore, the Biliary Clearance of ouabain and digoxin with regard to plasma concentration were 21.9-fold and 4.1-fold lower in Slco1a4−/− mice, respectively, accompanied with a marked reduction in their Kp,liver, whereas the systemic Clearance of ouabain, but not digoxin, was reduced significantly in Slco1a4−/− mice. These results suggest that Oatp1a4 plays a major role in the hepatic accumulation of cardiac glycosides in mice.

  • in vivo Biliary Clearance should be predicted by intrinsic Biliary Clearance in sandwich cultured hepatocytes
    Drug Metabolism and Disposition, 2012
    Co-Authors: Masanori Nakakariya, Midori Ono, Nobuyuki Amano, Toshiya Moriwaki, Kazuya Maeda, Yuichi Sugiyama
    Abstract:

    It has been reported that in vivo Biliary Clearance can be predicted using sandwich-cultured rat and human hepatocytes. The predicted apparent Biliary Clearance (CL(bile, app)) from sandwich- cultured rat hepatocytes (SCRH) based on medium concentrations correlates to in vivo CL(bile, app) based on plasma concentrations of angiotensin II receptor blockers (ARBs), HMG-CoA reductase inhibitors (statins), β-lactam antibiotics, and topotecan. However, the predicted Biliary Clearance from SCRH was 7- to 300-fold lower than in vivo Biliary Clearance. We speculated that the process of Biliary excretion might not have been evaluated using sandwich-cultured hepatocytes. To evaluate this issue, intrinsic Biliary Clearance (CL(bile, int)) based on intracellular compound concentrations was evaluated to investigate the in vitro-in vivo correlation of this process among ARBs, statins, β-lactam antibiotics, and topotecan. Intrinsic Biliary Clearance in SCRH correlated to in vivo values obtained by constant intravenous infusion of six compounds, but not rosuvastatin and cefmetazole, to rats. Moreover, differences between SCRH and in vivo CL(bile, int) (0.7-6-fold) were much smaller than those of CL(bile, app) (7-300-fold). Therefore, in vivo CL(bile, int) is more accurately reflected using SCRH than CL(bile, app). In conclusion, to predict in vivo Biliary Clearance more accurately, CL(bile, int) should be evaluated instead of CL(bile, app) between SCRH and in vivo.

  • increasing systemic exposure of methotrexate by active efflux mediated by multidrug resistance associated protein 3 mrp3 abcc3
    Journal of Pharmacology and Experimental Therapeutics, 2008
    Co-Authors: Yoshiaki Kitamura, John D Schuetz, Masakazu Hirouchi, Hiroyuki Kusuhara, Yuichi Sugiyama
    Abstract:

    The aim of this study was to investigate the functional importance of multidrug resistance-associated protein (Mrp)3/ Abcc3 and Mrp4/ Abcc4 in the pharmacokinetics of methotrexate. Compared with the corresponding wild-type mice, the plasma concentrations of methotrexate given orally were similar in Abcc4 -/- mice and were significantly lower in Abcc3 -/- mice. Pharmacokinetic parameters related to hepatoBiliary transport were determined under steady-state conditions in wild-type and Abcc3 -/- mice that were given a constant intravenous infusion of methotrexate. The Biliary Clearance, based on the plasma concentration, was 1.6-fold greater in Abcc3 -/- mice than in wild-type mice (23 and 15 ml/min/kg, respectively, P < 0.05). Because the basolateral uptake and canalicular efflux Clearances of methotrexate were similar in wild-type and Abcc3 -/- mice, this result suggests that the basolateral efflux Clearance of methotrexate is decreased in the liver of Abcc3 -/- mice. Furthermore, a lower fraction of absorption of methotrexate ( F a F g) was suggested in Abcc3 -/- mice (0.49 and 0.29 in wild-type and Abcc3 - / - mice, respectively). The mucosal-to-serosal transport rate of methotrexate, determined in vitro using everted sacs, was highest in the duodenum and was significantly decreased in Abcc3 -/- mice compared with wild-type mice. This is ascribed to the reduced intrinsic efflux Clearance of methotrexate across the serosal membrane (22 and 5.3 μl/min/sac in wild-type and Abcc3 - / - mice, respectively, P < 0.05). These results suggest that Mrp3 mediates basolateral efflux of methotrexate in the liver and duodenum, thereby serving to increase systemic exposure, whereas Mrp4 is likely to play only a limited role in the systemic methotrexate exposure.

  • prediction of in vivo Biliary Clearance from the in vitro transcellular transport of organic anions across a double transfected madin darby canine kidney ii monolayer expressing both rat organic anion transporting polypeptide 4 and multidrug resistan
    Molecular Pharmacology, 2004
    Co-Authors: Makoto Sasaki, Jun Aoki, Hiroshi Suzuki, Peter J. Meier, Yuichi Sugiyama
    Abstract:

    We have proposed previously that the evaluation of transcellular transport across the double-transfected Madin-Darby canine kidney II (MDCK II) monolayer that expresses both human organic anion transporting polypeptide 4 (OATP2/SLC21A6) and multidrug resistance associated protein 2 (MRP2/ABCC2) on the basal and apical membranes, respectively, may be useful in characterizing human Biliary excretion (J Biol Chem 277: 6497-6503, 2002). However, to demonstrate that this in vitro system represents in vivo Biliary excretion, it is essential to compare in vitro data with in vivo Biliary excretion. The problem is that we cannot determine the human Biliary excretion for many ligands. In the present study, we have established a double-transfected MDCK II monolayer that expresses both rat Oatp4/Slc21a10 and Mrp2/Abcc2 on the basal and apical membranes, respectively, for the purpose of quantitatively comparing the Clearance for transcellular transport with that for in vivo Biliary excretion. The basal-to-apical transport of 17beta-estradiol-17beta-d-glucuronide, pravastatin, leukotriene C(4), cyclo-[D-Asp-Pro-d-Val-Leu-d-Trp] (BQ123), temocaprilat, and taurolithocholate 3-sulfate was significantly higher than that in the opposite direction in the double transfectant. Kinetic analysis suggested that that the rate-determining step of these compounds is the uptake process. The extent of the transcellular transport across the rat double-transfectant correlated well with that across the double-transfectant for human OATP2/SLC21A6 and MRP2/ABCC2. Moreover, considering the scaling factor, the Clearance values for in vitro transcellular transport correlated well with those for in vivo Biliary Clearance. The double-transfected MDCK II monolayer may be useful in analyzing the hepatic vectorial transport of organic anions and in predicting in vivo Biliary Clearance.

  • mechanisms of impaired Biliary excretion of acetaminophen glucuronide after acute phenobarbital treatment or phenobarbital pretreatment
    Drug Metabolism and Disposition, 2002
    Co-Authors: Hao Xiong, Yuichi Sugiyama, Hiroshi Suzuki, Peter J. Meier, Gary M Pollack, Kim L. R. Brouwer
    Abstract:

    Previous studies have demonstrated that phenobarbital (PB) significantly impairs the Biliary excretion of acetaminophen glucuronide (AG) in rats. Studies also suggested that Mrp2 mediates AG Biliary excretion, and Mrp3 is involved in AG basolateral export. It was hypothesized that inhibition of Mrp2-mediated AG transport by PB or PB metabolites, and PB induction of Mrp3, may contribute to the impaired Biliary excretion of AG by PB. In the present study, the hepatoBiliary transport of AG in single-pass isolated perfused Wistar and TR − rat livers was investigated. The AG Biliary Clearance was markedly decreased, and the AG basolateral Clearance was significantly increased in TR − rat livers. Uptake of AG by Mrp2 and Mrp3, and inhibition of Mrp2- and Mrp3-mediated transport by PB and major PB metabolites, were investigated with rat Mrp2- or Mrp3-expressing Sf9 cell plasma membrane vesicles (Sf9-PMVs). AG was transported by Mrp3 ( K m ≈ 0.91 mM). Net ATP-dependent AG uptake into Mrp2-expressing Sf9-PMVs could not be detected directly. However, AG significantly inhibited Mrp2-mediated 5-(and 6)-carboxy-2′,7′-dichlorofluorescein (CDF) transport. p -Hydroxyphenobarbital glucuronide ( p -OHPBG), but not PB or p -hydroxyphenobarbital, significantly inhibited Mrp2-mediated CDF transport. The IC 50 values for p -OHPBG inhibition of Mrp2-mediated CDF uptake and Mrp3-mediated AG transport were similar (∼0.68 and 0.46 mM, respectively). PB treatment (80 mg/kg/day × 4 days) markedly increased hepatic Mrp3 expression in Wistar rats. In conclusion, inhibition of Mrp2-mediated AG transport by p -OHPBG provided one possible explanation for the impaired Biliary excretion of AG after acute PB treatment. However, impaired Biliary excretion of AG after PB pretreatment may be attributed primarily to the induction of hepatic Mrp3 by PB.

Akira Tsuji - One of the best experts on this subject based on the ideXlab platform.

  • involvement of multidrug resistance associated protein 2 abcc2 in molecular weight dependent Biliary excretion of β lactam antibiotics
    Drug Metabolism and Disposition, 2008
    Co-Authors: Yukio Kato, Ikumi Tamai, Seiko Takahara, Sayaka Kato, Yoshiyuki Kubo, Hikaru Yabuuchi, Akira Tsuji
    Abstract:

    In the present study, we attempted to identify the membrane permeation process(es) primarily involved in the molecular-weight-dependent Biliary excretion of β-lactam antibiotics. A search of the literature indicated that the molecular weight threshold operates mainly in the transport process across bile canalicular membranes. We confirmed that Biliary Clearance of the model Biliary-excretion-type cephalosporin cefoperazone was reduced to 10% of the control in Eisai hyperbilirubinemic rats, which are genetically deficient in multidrug resistance-associated protein (Mrp) 2, indicating that Mrp2 plays a major role as an efflux transporter on the canalicular membranes. ATP-dependent uptake of several cephalosporins including cefoperazone, cefbuperazone, cefpiramide, and ceftriaxone, all of which are mainly excreted into bile, was confirmed in membrane vesicles from Sf9 cells transfected with rat Mrp2. Both the inhibitory potency of the cephalosporins for Mrp2-mediated transport and the uptake of cephalosporins by Mrp2-expressing vesicles were molecular weight-dependent, suggesting that Mrp2 is one of the major transporters involved in molecular weight-dependent Biliary excretion. An uptake study in membrane vesicles of Sf9 cells transfected with breast cancer resistance protein (Bcrp) revealed that Bcrp accepts cefoperazone, cefbuperazone, cefpiramide, cefotetan, ceftriaxone, cefotiam, cefamandole, and cefazolin as substrates, and Bcrp-mediated transport was also molecular weight-dependent, suggesting that Bcrp also contributes to molecular weight-dependent Biliary excretion of β-lactam antibiotics in rats.

  • involvement of multiple transport systems in the disposition of an active metabolite of a prodrug type new quinolone antibiotic prulifloxacin
    Drug Metabolism and Pharmacokinetics, 2003
    Co-Authors: Yukihiro Yagi, Yukio Kato, Sachiyo Shibutani, Naoko Hodoshima, Kazuya Ishiwata, Noriko Okudaira, Qing Li, Akira Tsuji
    Abstract:

    Summary: Prulifloxacin is a prodrug­type new quinolone. The purpose of this study is to clarify the mechanism of Biliary excretion and brain distribution of its active metabolite,UFX. UFX was efficiently excreted into the bile in rats,with its concentration in the bile being 30–60 times higher than that in plasma. The in vivo disposition study revealed that multidrug resistance­associated protein 2 (MRP2) was involved in the Biliary excretion of glucuronide metabolite,but not of the unchanged UFX. A transport study using a P­glycoprotein (P­gp) overexpressing cell line,LLC­GA5­COL150,showed that UFX was a substrate of P­gp. Nevertheless,the Biliary Clearance (CLbile) of UFX in P­gp­gene­deficient mice was not different from that in the normal mice,although the concentration in the liver was slightly higher than that in the normal mice. These observations suggest that multiple transport systems are involved in the Biliary excretion of UFX,with minor contribution of P­gp. The distribution of UFX in the rat brain was quite low,and its tissue to plasma concentration ratio (Kp) in the brain was much less than the unity and was increased by cyclosporin A. The Kp in the brain of mdr1a/1b(­/­) mice was higher than that in the normal mice,suggesting that efflux by P­gp played a major role in the limited brain distribution of UFX.

  • differences in the hepatoBiliary transport of two quinolone antibiotics grepafloxacin and lomefloxacin in the rat
    Biopharmaceutics & Drug Disposition, 1999
    Co-Authors: Hiroyuki Sasabe, Yukio Kato, Tetsuya Terasaki, Akira Tsuji, Yuichi Sugiyama
    Abstract:

    The Biliary excretion of grepafloxacin (GPFX) was compared with that of lomefloxacin (LFLX) in rats. The Biliary Clearances (Cl(plasma)(bile)) of GPFX was 2.9 times greater than LFLX based on the plasma concentration reached during constant intravenous (i.v.) infusion. The liver-plasma unbound concentration ratio, K(pu), of GPFX (1.7) was also higher than that of LFLX (0.7). The hepatic uptake Clearance, assessed from an integration plot analysis, of GPFX was comparable with the hepatic blood flow rate, and 1.5 times that of LFLX, indicating that membrane transport in the uptake process is more efficient for GPFX. This was also supported by the difference between the uptake Clearance of GPFX and LFLX in isolated rat hepatocytes. The bile-liver unbound concentration ratio of GPFX and LFLX was approximately 6 and 3, respectively, and the Biliary Clearance based on the unbound liver concentration of GPFX was 1.8 times that of LFLX. These results suggest that the concentrative transport of GPFX also across the canalicular membrane was more efficient than that of LFLX. Thus, the membrane transport activity via both sinusoidal and canalicular membranes determines the net excretion of each compound.

  • stereoselective hepatoBiliary transport of the quinolone antibiotic grepafloxacin and its glucuronide in the rat
    Journal of Pharmacology and Experimental Therapeutics, 1998
    Co-Authors: Hiroyuki Sasabe, Yukio Kato, Akira Tsuji, Yuichi Sugiyama
    Abstract:

    A comparative pharmacokinetic study was performed for the optical isomers of grepafloxacin (GPFX), an asymmetric quinolone antibiotic. At steady state in rats receiving a constant infusion of each epimer, R(+)-GPFX and S(−)-GPFX, no marked difference between epimers was observed in plasma concentrations or in Biliary and urinary excretion rates. The 3-glucuronides of GPFX are diastereomers. The Biliary Clearance, defined by the liver concentration of the 3-glucuronide of R(+)-GPFX (R-GPFX-Glu), was twice that of the 3-glucuronide of S(−)-GPFX (S-GPFX-Glu). Marked ATP dependence was observed in the uptake of both R-GPFX-Glu and S-GPFX-Glu by bile canalicular membrane vesicles. The ATP-dependent uptake of R-GPFX-Glu was also greater than that of S-GPFX-Glu. Kinetic analysis of the uptake of these glucuronides by bile canalicular membrane vesicles indicated that the affinity (1/ K m) of S-GPFX-Glu for the transporter was 1.7 times higher than that of R-GPFX-Glu, whereas the V max of R-GPFX-Glu was 2.9 times greater than that of S-GPFX-Glu. The uptake of both glucuronides was reduced in mutant strain Eisai-hyperbilirubinemia rats, which have a hereditary defect in the bile canalicular multispecific organic anion transport system. Both glucuronides inhibited the ATP-dependent uptake of DNP-SG, a typical substrate for the bile canalicular multispecific organic anion transport system in a concentration-dependent manner, with a K i of 21.5 μM and 8.8 μM for R-GPFX-Glu and S-GPFX-Glu, respectively. These K i values were comparable with the corresponding Michaelis-Menten constant values for their uptake (17.3 μM and 10.1 μM, respectively). It is concluded that a major part of the stereoselective transport of these glucuronides across the bile canalicular membrane is mediated by a transporter that is deficient in Eisai-hyperbilirubinemia rats—possibly by the bile canalicular multispecific organic anion transport system.

  • Carrier-mediated mechanism for the Biliary excretion of the quinolone antibiotic grepafloxacin and its glucuronide in rats. J Pharmacol Exp Ther 284:1033–1039
    1998
    Co-Authors: Hiroyuki Sasabe, Akira Tsuji, Yuichi Sugiyama
    Abstract:

    ABSTRACT Grepafloxacin (GPFX) has a comparatively greater hepatoBiliary transport than other quinolone antibiotics. The Biliary excretion mechanism of GPFX was investigated in a series of in vivo and in vitro studies with Sprague-Dawley rats and the mutant strain Eisai-hyperbilirubinemia rats (EHBR), which have a hereditary defect in their bile canalicular multispecific organic anion transport system (cMOAT). The Biliary excretion of the parent drug in EHBR was 38% of that in normal rats, whereas the 3-glucuronide, a main metabolite of GPFX, was scarcely excreted into the bile in EHBR. To clarify the Biliary excretion mechanism of GPFX, studies of uptake by bile canalicular membrane vesicle (CMV) were performed. ATP dependence was observed in the uptake of GPFX by CMV, although the extent was not very marked, whereas no ATP-dependent uptake was observed by CMV prepared from EHBR. An inhibition study of the ATPdependent uptake of the glutathione conjugate, 2,4-dinitrophenyl-S-glutathione (DNP-SG), a typical substrate for cMOAT, was performed in order to differentiate among the affinities of six quinolone antibiotics for this transporter. All quinolone antibiotics inhibited the ATP-dependent uptake of DNP-SG with different half-inhibition concentrations (IC 50 ), and GPFX had the lowest IC 50 value. The uptake of GPFX-glucuronide by CMV from normal rats showed a marked ATP dependence, whereas there was little ATP-dependent uptake in EHBR. The K m value (7.2 M) for the higher-affinity component of the glucuronide uptake was comparable to the K i value (9.2 M) of the glucuronide in terms of inhibition of the ATP-dependent uptake of DNP-SG, which indicates that DNP-SG and the glucuronide may share the same transporter, cMOAT. The K i value of the glucuronide observed in this inhibition was less than 1/200 that of the parent, which suggests that the glucuronide had a much higher affinity than the parent drug. These results lead us to conclude that at least a part of the GPFX transport and a major part of its glucuronide transport across the bile canalicular membrane are by a primary active transport mechanism mediated by cMOAT. The total body Clearance of many NQ occurs mainly via metabolic elimination and urinary excretion, whereas the Biliary Clearance of newly developed quinolones such as GPFX and SPFX is greater than for other N

Jashvant D Unadkat - One of the best experts on this subject based on the ideXlab platform.

  • when does the rate determining step in the hepatic Clearance of a drug switch from sinusoidal uptake to all hepatoBiliary Clearances implications for predicting drug drug interactions
    Drug Metabolism and Disposition, 2018
    Co-Authors: Gabriela Patileavrana, Jashvant D Unadkat
    Abstract:

    For dual transporter/enzyme substrate drugs, the extended Clearance model (ECM) can be used to predict the rate-determining step(s) (RDS) of a drug and hence predict its drug-drug interaction (DDI) liabilities (i.e. transport, metabolism, or both). If the RDS of the hepatic Clearance of the drug is sinusoidal uptake Clearance (CLsin), even if the drug is mainly eliminated by hepatic metabolism, its DDI liability (as viewed from changes to systemic drug concentrations) is expected to be inhibition or induction of uptake transporters but not hepatic metabolic enzymes. However, this is true only if the condition required to maintain CLsin as the RDS is maintained. Here, we illustrate through theoretical simulations that the RDS condition may be violated in the presence of a DDI. That is, the RDS of a drug can switch from CLsin to all hepatoBiliary Clearances (i.e. metabolic/Biliary Clearance [CLmet+bile] as well as CLsin) leading to unexpected systemic DDI9s, such as metabolic DDI9s when only transporter DDI9s are anticipated. As expected, these analyses revealed that the RDS switch depends on the ratio of CLmet+bile to sinusoidal efflux Clearance (CLsef). Additional analyses revealed that for intravenously administered drugs, the RDS switch also depends on the magnitude of CLsin. We analyzed published in vitro quantified hepatoBiliary Clearances and observed that most drugs have CLmet+bile/CLsef ratio

  • interindividual variability in the hepatic expression of the human breast cancer resistance protein bcrp abcg2 effect of age sex and genotype
    Journal of Pharmaceutical Sciences, 2013
    Co-Authors: Bhagwat Prasad, Yurong Lai, Yvonne S Lin, Jashvant D Unadkat
    Abstract:

    Breast cancer resistance protein (BCRP), an efflux transporter expressed at the bile canalicular membrane, is responsible for the Biliary Clearance of many drugs. Data on the interindividual variability of hepatic BCRP expression are needed for in vitro to in vivo extrapolation of the Biliary Clearance of a BCRP substrate drug. Therefore, we measured the expression of BCRP in human livers (n = 65) by liquid chromatography coupled with tandem mass spectrometry. A calibration curve was generated using a synthetic signature peptide (SSLLDVLAAR) as the calibrator and the corresponding synthetic stable isotope-labeled peptide as the internal standard. The analytical method was accurate and precise. BCRP expression in 50 livers, where it was measurable, was 137.9 ± 42.1 atmol/µg of membrane protein (range 69.7-246.4 atmol/µg of membrane protein). BCRP expression was not associated with age (7-70 years), sex, or mRNA expression. BCRP expression in livers with the variant C421A (rs2231142) allele (14 heterozygotes, two homozygotes; among these, eight livers were below lower limit of quantification) was significantly lower than that in the wild-type livers (p < 0.002). Integration of these data with data on the hepatic expression of other transporters will allow refinement of physiologically based pharmacokinetic models to predict the pharmacokinetics, hepatic exposure, and drug-drug interactions of drugs (and/or their metabolites).

Yukio Kato - One of the best experts on this subject based on the ideXlab platform.

  • involvement of multidrug resistance associated protein 2 abcc2 in molecular weight dependent Biliary excretion of β lactam antibiotics
    Drug Metabolism and Disposition, 2008
    Co-Authors: Yukio Kato, Ikumi Tamai, Seiko Takahara, Sayaka Kato, Yoshiyuki Kubo, Hikaru Yabuuchi, Akira Tsuji
    Abstract:

    In the present study, we attempted to identify the membrane permeation process(es) primarily involved in the molecular-weight-dependent Biliary excretion of β-lactam antibiotics. A search of the literature indicated that the molecular weight threshold operates mainly in the transport process across bile canalicular membranes. We confirmed that Biliary Clearance of the model Biliary-excretion-type cephalosporin cefoperazone was reduced to 10% of the control in Eisai hyperbilirubinemic rats, which are genetically deficient in multidrug resistance-associated protein (Mrp) 2, indicating that Mrp2 plays a major role as an efflux transporter on the canalicular membranes. ATP-dependent uptake of several cephalosporins including cefoperazone, cefbuperazone, cefpiramide, and ceftriaxone, all of which are mainly excreted into bile, was confirmed in membrane vesicles from Sf9 cells transfected with rat Mrp2. Both the inhibitory potency of the cephalosporins for Mrp2-mediated transport and the uptake of cephalosporins by Mrp2-expressing vesicles were molecular weight-dependent, suggesting that Mrp2 is one of the major transporters involved in molecular weight-dependent Biliary excretion. An uptake study in membrane vesicles of Sf9 cells transfected with breast cancer resistance protein (Bcrp) revealed that Bcrp accepts cefoperazone, cefbuperazone, cefpiramide, cefotetan, ceftriaxone, cefotiam, cefamandole, and cefazolin as substrates, and Bcrp-mediated transport was also molecular weight-dependent, suggesting that Bcrp also contributes to molecular weight-dependent Biliary excretion of β-lactam antibiotics in rats.

  • involvement of multiple transport systems in the disposition of an active metabolite of a prodrug type new quinolone antibiotic prulifloxacin
    Drug Metabolism and Pharmacokinetics, 2003
    Co-Authors: Yukihiro Yagi, Yukio Kato, Sachiyo Shibutani, Naoko Hodoshima, Kazuya Ishiwata, Noriko Okudaira, Qing Li, Akira Tsuji
    Abstract:

    Summary: Prulifloxacin is a prodrug­type new quinolone. The purpose of this study is to clarify the mechanism of Biliary excretion and brain distribution of its active metabolite,UFX. UFX was efficiently excreted into the bile in rats,with its concentration in the bile being 30–60 times higher than that in plasma. The in vivo disposition study revealed that multidrug resistance­associated protein 2 (MRP2) was involved in the Biliary excretion of glucuronide metabolite,but not of the unchanged UFX. A transport study using a P­glycoprotein (P­gp) overexpressing cell line,LLC­GA5­COL150,showed that UFX was a substrate of P­gp. Nevertheless,the Biliary Clearance (CLbile) of UFX in P­gp­gene­deficient mice was not different from that in the normal mice,although the concentration in the liver was slightly higher than that in the normal mice. These observations suggest that multiple transport systems are involved in the Biliary excretion of UFX,with minor contribution of P­gp. The distribution of UFX in the rat brain was quite low,and its tissue to plasma concentration ratio (Kp) in the brain was much less than the unity and was increased by cyclosporin A. The Kp in the brain of mdr1a/1b(­/­) mice was higher than that in the normal mice,suggesting that efflux by P­gp played a major role in the limited brain distribution of UFX.

  • inhibition of Biliary excretion of methotrexate by probenecid in rats quantitative prediction of interaction from in vitro data
    Journal of Pharmacology and Experimental Therapeutics, 2001
    Co-Authors: Kaoru Ueda, Yukio Kato, Kanji Komatsu, Yuichi Sugiyama
    Abstract:

    This study was designed to establish a strategy to predict drug interactions involving Biliary excretion. The interaction between methotrexate and probenecid was examined as an interaction model since this interaction has already been clinically reported. Coadministration of probenecid reduced the Biliary Clearance of methotrexate in a dose-dependent manner in rats. This inhibition by probenecid was confirmed in vivo both in the uptake and excretion processes of methotrexate across sinusoidal and canalicular membranes, respectively. That is, both hepatic uptake Clearance, assessed in integration plot analysis, and steady-state Biliary Clearance defined with respect to hepatic unbound methotrexate, were reduced in the presence of probenecid. Probenecid inhibited the active transport of methotrexate both in isolated hepatocytes and canalicular membrane vesicles, confirming the interaction at those two membranes. The degree of inhibition of the uptake and excretion processes found in vivo was comparable with the predicted values using the inhibition constant assessed in isolated hepatocytes and canalicular membranes, respectively. This suggests that the interaction at each membrane transport process can be quantitatively estimated from in vitro data. We have also proposed the method to predict the degree of inhibition of the net excretion from circulating plasma into the bile, the predicted values being also comparable with the inhibition actually found in vivo. The present analysis demonstrates a strategic rationale for predicting drug interactions involving Biliary excretion using in vitro systems to avoid any false negative predictions.

  • both cmoat mrp2 and another unknown transporter s are responsible for the Biliary excretion of glucuronide conjugate of the nonpeptide angiotensin ii antagonist telmisaltan
    Drug Metabolism and Disposition, 2000
    Co-Authors: Yukio Kato, Yuichi Sugiyama, Takashi Igarashi, Akiko Nishino
    Abstract:

    Canalicular multispecific organic anion transporter (cMOAT/MRP2) is known to play a major role in the transport of anionic xenobiotics including many types of glucuronide and glutathione conjugates across the bile canalicular membrane. In the present study, the Biliary excretion of telmisartan (BIBR 277) and its glucuronide was examined in Sprague-Dawley rats (SDRs) and also in mutant strain Eisai-hyperbilirubinemic rats (EHBR), which have a hereditary defect in cMOAT/MRP2. Only a minimal difference was observed in the time profile of the plasma concentration of total radioactivity after administration of an i.v. bolus of BIBR 277. About 45% of the administered dose was excreted into bile up to 240 min in both strains, most of the radioactivity in the bile being BIBR 277 glucuronide. No significant difference was observed in the Biliary excretion of BIBR 277 and its glucuronide between SDRs and EHBR although the plasma disappearance of BIBR 277 glucuronide was delayed in EHBR. To explain these data, the extent of glucuronidation of BIBR 277 by liver microsomes was examined in both strains. The V max value for the formation of BIBR 277 glucuronide was 2 to 3 times higher in EHBR than in SDRs, whereas both strains had similar K mvalues. After an i.v. bolus administration of BIBR 277 glucuronide, its plasma disappearance was delayed in EHBR, the Biliary Clearance in EHBR being about half that in SDRs. These results suggest that BIBR 277 glucuronide is transported by both cMOAT/MRP2 and another transporter that is also expressed in EHBR, and that the BIBR 277 glucuronidation is enhanced in EHBR, resulting in comparable excretion of glucuronide in both strains.

  • differences in the hepatoBiliary transport of two quinolone antibiotics grepafloxacin and lomefloxacin in the rat
    Biopharmaceutics & Drug Disposition, 1999
    Co-Authors: Hiroyuki Sasabe, Yukio Kato, Tetsuya Terasaki, Akira Tsuji, Yuichi Sugiyama
    Abstract:

    The Biliary excretion of grepafloxacin (GPFX) was compared with that of lomefloxacin (LFLX) in rats. The Biliary Clearances (Cl(plasma)(bile)) of GPFX was 2.9 times greater than LFLX based on the plasma concentration reached during constant intravenous (i.v.) infusion. The liver-plasma unbound concentration ratio, K(pu), of GPFX (1.7) was also higher than that of LFLX (0.7). The hepatic uptake Clearance, assessed from an integration plot analysis, of GPFX was comparable with the hepatic blood flow rate, and 1.5 times that of LFLX, indicating that membrane transport in the uptake process is more efficient for GPFX. This was also supported by the difference between the uptake Clearance of GPFX and LFLX in isolated rat hepatocytes. The bile-liver unbound concentration ratio of GPFX and LFLX was approximately 6 and 3, respectively, and the Biliary Clearance based on the unbound liver concentration of GPFX was 1.8 times that of LFLX. These results suggest that the concentrative transport of GPFX also across the canalicular membrane was more efficient than that of LFLX. Thus, the membrane transport activity via both sinusoidal and canalicular membranes determines the net excretion of each compound.