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Pang KS, Lu WI, Mulder GJ. After 50 Years of Hepatic Clearance Models, Where Should We Go from Here? Improvements and Implications for Physiologically Based Pharmacokinetic Modeling. Drug Metab Dispos 2024; 52:919-931. [PMID: 39013583 DOI: 10.1124/dmd.124.001649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 04/25/2024] [Indexed: 07/18/2024] Open
Abstract
There is overwhelming preference for application of the unphysiologic, well-stirred model (WSM) over the parallel tube model (PTM) and dispersion model (DM) to predict hepatic drug clearance, CLH , despite that liver blood flow is dispersive and closer to the DM in nature. The reasoning is the ease in computation relating the hepatic intrinsic clearance ( CLint ), hepatic blood flow ( QH ), unbound fraction in blood ( fub ) and the transmembrane clearances ( CLin and CLef ) to CLH for the WSM. However, the WSM, being the least efficient liver model, predicts a lower EH that is associated with the in vitro CLint ( Vmax / Km ), therefore requiring scale-up to predict CLH in vivo. By contrast, the miniPTM, a three-subcompartment tank-in-series model of uniform enzymes, closely mimics the DM and yielded similar patterns for CLint versus EH , substrate concentration [S] , and KL / B , the tissue to outflow blood concentration ratio. We placed these liver models nested within physiologically based pharmacokinetic models to describe the kinetics of the flow-limited, phenolic substrate, harmol, using the WSM (single compartment) and the miniPTM and zonal liver models (ZLMs) of evenly and unevenly distributed glucuronidation and sulfation activities, respectively, to predict CLH For the same, given CLint ( Vmax and Km ), the WSM again furnished the lowest extraction ratio ( EH,WSM = 0.5) compared with the miniPTM and ZLM (>0.68). Values of EH,WSM were elevated to those for EH, PTM and EH, ZLM when the Vmax s for sulfation and glucuronidation were raised 5.7- to 1.15-fold. The miniPTM is easily manageable mathematically and should be the new normal for liver/physiologic modeling. SIGNIFICANCE STATEMENT: Selection of the proper liver clearance model impacts strongly on CLH predictions. The authors recommend use of the tank-in-series miniPTM (3 compartments mini-parallel tube model), which displays similar properties as the dispersion model (DM) in relating CLint and [ S ] to CLH as a stand-in for the DM, which best describes the liver microcirculation. The miniPTM is readily modified to accommodate enzyme and transporter zonation.
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Affiliation(s)
- K Sandy Pang
- Leslie Dan Faculty of Pharmacy, University of Toronto, Ontario, Canada (K.S.P., W.I.L.) and Department of Toxicology, Leiden Academic Centre for Drug Research, Leiden University, The Netherlands (G.J.M.)
| | - Weijia Ivy Lu
- Leslie Dan Faculty of Pharmacy, University of Toronto, Ontario, Canada (K.S.P., W.I.L.) and Department of Toxicology, Leiden Academic Centre for Drug Research, Leiden University, The Netherlands (G.J.M.)
| | - Gerard J Mulder
- Leslie Dan Faculty of Pharmacy, University of Toronto, Ontario, Canada (K.S.P., W.I.L.) and Department of Toxicology, Leiden Academic Centre for Drug Research, Leiden University, The Netherlands (G.J.M.)
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Fader Kaiser CM, Romano PS, Vanrell MC, Pocognoni CA, Jacob J, Caruso B, Delgui LR. Biogenesis and Breakdown of Lipid Droplets in Pathological Conditions. Front Cell Dev Biol 2022; 9:826248. [PMID: 35198567 PMCID: PMC8860030 DOI: 10.3389/fcell.2021.826248] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 12/22/2021] [Indexed: 12/17/2022] Open
Abstract
Lipid droplets (LD) have long been considered as mere fat drops; however, LD have lately been revealed to be ubiquitous, dynamic and to be present in diverse organelles in which they have a wide range of key functions. Although incompletely understood, the biogenesis of eukaryotic LD initiates with the synthesis of neutral lipids (NL) by enzymes located in the endoplasmic reticulum (ER). The accumulation of NL leads to their segregation into nanometric nuclei which then grow into lenses between the ER leaflets as they are further filled with NL. The lipid composition and interfacial tensions of both ER and the lenses modulate their shape which, together with specific ER proteins, determine the proneness of LD to bud from the ER toward the cytoplasm. The most important function of LD is the buffering of energy. But far beyond this, LD are actively integrated into physiological processes, such as lipid metabolism, control of protein homeostasis, sequestration of toxic lipid metabolic intermediates, protection from stress, and proliferation of tumours. Besides, LD may serve as platforms for pathogen replication and defense. To accomplish these functions, from biogenesis to breakdown, eukaryotic LD have developed mechanisms to travel within the cytoplasm and to establish contact with other organelles. When nutrient deprivation occurs, LD undergo breakdown (lipolysis), which begins with the LD-associated members of the perilipins family PLIN2 and PLIN3 chaperone-mediated autophagy degradation (CMA), a specific type of autophagy that selectively degrades a subset of cytosolic proteins in lysosomes. Indeed, PLINs CMA degradation is a prerequisite for further true lipolysis, which occurs via cytosolic lipases or by lysosome luminal lipases when autophagosomes engulf portions of LD and target them to lysosomes. LD play a crucial role in several pathophysiological processes. Increased accumulation of LD in non-adipose cells is commonly observed in numerous infectious diseases caused by intracellular pathogens including viral, bacterial, and parasite infections, and is gradually recognized as a prominent characteristic in a variety of cancers. This review discusses current evidence related to the modulation of LD biogenesis and breakdown caused by intracellular pathogens and cancer.
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Affiliation(s)
- Claudio M Fader Kaiser
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
| | - Patricia S Romano
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
| | - M Cristina Vanrell
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
| | - Cristian A Pocognoni
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
| | - Julieta Jacob
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
| | - Benjamín Caruso
- Instituto de Investigaciones Biologicas y Tecnologicas, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Cordoba, Cordoba, Argentina
| | - Laura R Delgui
- CONICET Dr. Mario H. Burgos Institute of Histology and Embryology (IHEM), Mendoza, Argentina
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López Giuliani AC, Hernández E, Tohmé MJ, Taisne C, Roldán JS, García Samartino C, Lussignol M, Codogno P, Colombo MI, Esclatine A, Delgui LR. Human Cytomegalovirus Inhibits Autophagy of Renal Tubular Epithelial Cells and Promotes Cellular Enlargement. Front Cell Infect Microbiol 2020; 10:474. [PMID: 33042861 PMCID: PMC7522221 DOI: 10.3389/fcimb.2020.00474] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 07/31/2020] [Indexed: 12/26/2022] Open
Abstract
Human Cytomegalovirus (HCMV) is a frequent opportunistic pathogen in immunosuppressed patients, which can be involved in kidney allograft dysfunction and rejection. In order to study the pathophysiology of HCMV renal diseases, we concentrated on the impact of HCMV infection on human renal tubular epithelial HK-2 cells. Our aim was to develop a model of infection of HK-2 cells by using the viral strain TB40/E, that contains the extended cell tropism of clinical isolates and the efficient viral multiplication in cell culture of laboratory-adapted strains. We observed that HK-2 cells can be infected by HCMV and expressed viral antigens, but they do not produce extracellular viral particles. We then studied the interplay of HCMV with ciliogenesis and autophagy. Primary cilium (PC) is a stress sensor important to maintain renal tissue homeostasis that projects from the apical side into the lumen of tubule cells. PC formation and length were not modified by HCMV infection. Autophagy, another stress response process critically required for normal kidney functions, was inhibited by HCMV in HK-2 cells with a reduction in the autophagic flux. HCMV classically induces an enlargement of infected cells in vivo and in vitro, and we observed that HCMV infection led to an enlargement of the HK-2 cell volume. Our results constitute therefore an excellent starting point to further explore the role of these mechanisms in renal cells dysfunction.
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Affiliation(s)
- Ana C López Giuliani
- Facultad de Ciencias Médicas, IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Eva Hernández
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - María J Tohmé
- Facultad de Ciencias Médicas, IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Facultad de Farmacia y Bioquímica, Universidad Juan Agustín Maza, Mendoza, Argentina
| | - Clémence Taisne
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Julieta S Roldán
- Instituto de Investigaciones Biotecnológicas (IIBIO), Universidad de San Martín, Buenos Aires, Argentina
| | | | - Marion Lussignol
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Patrice Codogno
- Institut Necker-Enfants Malades (INEM), INSERM U1151-CNRS UMR 8253, Paris, France.,The Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - María I Colombo
- Facultad de Ciencias Médicas, IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Audrey Esclatine
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Laura R Delgui
- Facultad de Ciencias Médicas, IHEM, Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
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4
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Hagos FT, Empey PE, Wang P, Ma X, Poloyac SM, Bayır H, Kochanek PM, Bell MJ, Clark RSB. Exploratory Application of Neuropharmacometabolomics in Severe Childhood Traumatic Brain Injury. Crit Care Med 2018; 46:1471-1479. [PMID: 29742587 PMCID: PMC6095742 DOI: 10.1097/ccm.0000000000003203] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVES To employ metabolomics-based pathway and network analyses to evaluate the cerebrospinal fluid metabolome after severe traumatic brain injury in children and the capacity of combination therapy with probenecid and N-acetylcysteine to impact glutathione-related and other pathways and networks, relative to placebo treatment. DESIGN Analysis of cerebrospinal fluid obtained from children enrolled in an Institutional Review Board-approved, randomized, placebo-controlled trial of a combination of probenecid and N-acetylcysteine after severe traumatic brain injury (Trial Registration NCT01322009). SETTING Thirty-six-bed PICU in a university-affiliated children's hospital. PATIENTS AND SUBJECTS Twelve children 2-18 years old after severe traumatic brain injury and five age-matched control subjects. INTERVENTION Probenecid (25 mg/kg) and N-acetylcysteine (140 mg/kg) or placebo administered via naso/orogastric tube. MEASUREMENTS AND MAIN RESULTS The cerebrospinal fluid metabolome was analyzed in samples from traumatic brain injury patients 24 hours after the first dose of drugs or placebo and control subjects. Feature detection, retention time, alignment, annotation, and principal component analysis and statistical analysis were conducted using XCMS-online. The software "mummichog" was used for pathway and network analyses. A two-component principal component analysis revealed clustering of each of the groups, with distinct metabolomics signatures. Several novel pathways with plausible mechanistic involvement in traumatic brain injury were identified. A combination of metabolomics and pathway/network analyses showed that seven glutathione-centered pathways and two networks were enriched in the cerebrospinal fluid of traumatic brain injury patients treated with probenecid and N-acetylcysteine versus placebo-treated patients. Several additional pathways/networks consisting of components that are known substrates of probenecid-inhibitable transporters were also identified, providing additional mechanistic validation. CONCLUSIONS This proof-of-concept neuropharmacometabolomics assessment reveals alterations in known and previously unidentified metabolic pathways and supports therapeutic target engagement of the combination of probenecid and N-acetylcysteine treatment after severe traumatic brain injury in children.
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Affiliation(s)
- Fanuel T. Hagos
- Center for Clinical Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA
| | - Philip E. Empey
- Center for Clinical Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA
- Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA
- Clinical and Translational Science Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Pengcheng Wang
- Center for Pharmacogenetics, University of Pittsburgh, Pittsburgh, PA
| | - Xiaochao Ma
- Center for Pharmacogenetics, University of Pittsburgh, Pittsburgh, PA
| | - Samuel M. Poloyac
- Center for Clinical Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA
- Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA
- Clinical and Translational Science Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Hülya Bayır
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
- Brain Care Institute, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA
| | - Patrick M. Kochanek
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
- Brain Care Institute, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Michael J. Bell
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
- Brain Care Institute, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA
- Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Pediatrics, Children’s National Health System, Washington, DC
| | - Robert S. B. Clark
- Clinical and Translational Science Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
- Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA
- Brain Care Institute, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA
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5
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Yu SM, Oh JM, Lee J, Lee-Kwon W, Jung W, Amblard F, Granick S, Cho YK. Substrate curvature affects the shape, orientation, and polarization of renal epithelial cells. Acta Biomater 2018; 77:311-321. [PMID: 30006316 DOI: 10.1016/j.actbio.2018.07.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 06/25/2018] [Accepted: 07/09/2018] [Indexed: 10/28/2022]
Abstract
The unique structure of kidney tubules is representative of their specialized function. Because maintaining tubular structure and controlled diameter is critical for kidney function, it is critical to understand how topographical cues, such as curvature, might alter cell morphology and biological characteristics. Here, we examined the effect of substrate curvature on the shape and phenotype of two kinds of renal epithelial cells (MDCK and HK-2) cultured on a microchannel with a broad range of principal curvature. We found that cellular architecture on curved substrates was closely related to the cell type-specific characteristics (stiffness, cell-cell adherence) of the cells and their density, as well as the sign and degree of curvature. As the curvature increased on convex channels, HK-2 cells, having lower cell stiffness and monolayer integrity than those of MDCK cells, aligned their in-plane axis perpendicular to the channel but did not significantly change in morphology. By contrast, MDCK cells showed minimal change in both morphology and alignment. However, on concave channels, both cell types were elongated and showed longitudinal directionality, although the changes in MDCK cells were more conservative. Moreover, substrate curvature contributed to cell polarization by enhancing the expression of apical and basolateral cell markers with height increase of the cells. Our study suggests curvature to be an important guiding principle for advanced tissue model developments, and that curved and geometrically ambiguous substrates can modulate the cellular morphology and phenotype. STATEMENT OF SIGNIFICANCE In many tissues, such as renal tubules or intestinal villi, epithelial layers exist in naturally curved forms, a geometry that is not reproduced by flat cultures. Because maintaining tubular structure is critical for kidney function, it is important to understand how topographical cues, such as curvature, might alter cell morphology and biological characteristics. We found that cellular architecture on curved substrates was closely related to cell type and density, as well as the sign and degree of the curvature. Moreover, substrate curvature contributed to cell polarization by enhancing the expression of apical and basolateral cell markers with height increase. Our results suggested that substrate curvature might contribute to cellular architecture and enhance the polarization of kidney tubule cells.
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Yu J, Zhu L, Zheng H, Gong X, Jiang H, Chen J, Li Y, Zheng H, Qi X, Wang Y, Hu M, Lu L, Liu Z. Sulfotransferases and Breast Cancer Resistance Protein Determine the Disposition of Calycosin in Vitro and in Vivo. Mol Pharm 2017; 14:2917-2929. [DOI: 10.1021/acs.molpharmaceut.7b00042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jia Yu
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Lijun Zhu
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Haihui Zheng
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Xia Gong
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Huangyu Jiang
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Jiamei Chen
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Yuhuan Li
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Hongming Zheng
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Xiaoxiao Qi
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Ying Wang
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Ming Hu
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
- Department of Pharmacological
and Pharmaceutical Sciences, College of Pharmacy, University of Houston, 1441 Moursund Street, Houston, Texas 77030, United States
| | - Linlin Lu
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Zhongqiu Liu
- International Institute
for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
- State Key Laboratory
of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau, China
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7
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Hofman J, Kučera R, Cihalova D, Klimes J, Ceckova M, Staud F. Olomoucine II, but not purvalanol A, is transported by breast cancer resistance protein (ABCG2) and P-glycoprotein (ABCB1). PLoS One 2013; 8:e75520. [PMID: 24116053 PMCID: PMC3792958 DOI: 10.1371/journal.pone.0075520] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/14/2013] [Indexed: 02/03/2023] Open
Abstract
Purine cyclin-dependent kinase inhibitors have been recognized as promising candidates for the treatment of various cancers; nevertheless, data regarding interaction of these substances with drug efflux transporters is still lacking. Recently, we have demonstrated inhibition of breast cancer resistance protein (ABCG2) by olomoucine II and purvalanol A and shown that these compounds are able to synergistically potentiate the antiproliferative effect of mitoxantrone, an ABCG2 substrate. In this follow up study, we investigated whether olomoucine II and purvalanol A are transported by ABCG2 and ABCB1 (P-glycoprotein). Using monolayers of MDCKII cells stably expressing human ABCB1 or ABCG2, we demonstrated that olomoucine II, but not purvalanol A, is a dual substrate of both ABCG2 and ABCB1. We, therefore, assume that pharmacokinetics of olomoucine II will be affected by both ABCB1 and ABCG2 transport proteins, which might potentially result in limited accumulation of the compound in tumor tissues or lead to drug-drug interactions. Pharmacokinetic behavior of purvalanol A, on the other hand, does not seem to be affected by either ABCG2 or ABCB1, theoretically favoring this drug in the potential treatment of efflux transporter-based multidrug resistant tumors. In addition, we observed intensive sulfatation of olomoucine II in MDCKII cell lines with subsequent active efflux of the metabolite out of the cells. Therefore, care should be taken when performing pharmacokinetic studies in MDCKII cells, especially if radiolabeled substrates are used; the generated sulfated conjugate may largely contaminate pharmacokinetic analysis and result in misleading interpretation. With regard to chemical structures of olomoucine II and purvalanol A, our data emphasize that even drugs with remarkable structure similarity may show different pharmacokinetic behavior such as interactions with ABC transporters or biotransformation enzymes.
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Affiliation(s)
- Jakub Hofman
- Department of Pharmacology and Toxicology, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
| | - Radim Kučera
- Department of Pharmaceutical Chemistry and Drug Analysis, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
| | - Daniela Cihalova
- Department of Pharmacology and Toxicology, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
| | - Jiri Klimes
- Department of Pharmaceutical Chemistry and Drug Analysis, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
| | - Martina Ceckova
- Department of Pharmacology and Toxicology, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
| | - Frantisek Staud
- Department of Pharmacology and Toxicology, Charles University in Prague, Faculty of Pharmacy, Hradec Kralove, Czech Republic
- * E-mail:
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Abstract
SIGNIFICANCE Glutathione (GSH) depletion is a central signaling event that regulates the activation of cell death pathways. GSH depletion is often taken as a marker of oxidative stress and thus, as a consequence of its antioxidant properties scavenging reactive species of both oxygen and nitrogen (ROS/RNS). RECENT ADVANCES There is increasing evidence demonstrating that GSH loss is an active phenomenon regulating the redox signaling events modulating cell death activation and progression. CRITICAL ISSUES In this work, we review the role of GSH depletion by its efflux, as an important event regulating alterations in the cellular redox balance during cell death independent from oxidative stress and ROS/RNS formation. We discuss the mechanisms involved in GSH efflux during cell death progression and the redox signaling events by which GSH depletion regulates the activation of the cell death machinery. FUTURE DIRECTIONS The evidence summarized here clearly places GSH transport as a central mechanism mediating redox signaling during cell death progression. Future studies should be directed toward identifying the molecular identity of GSH transporters mediating GSH extrusion during cell death, and addressing the lack of sensitive approaches to quantify GSH efflux.
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Affiliation(s)
- Rodrigo Franco
- Redox Biology Center, University of Nebraska-Lincoln, Lincoln, NE 68583, USA.
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9
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Fahrmayr C, König J, Auge D, Mieth M, Fromm MF. Identification of drugs and drug metabolites as substrates of multidrug resistance protein 2 (MRP2) using triple-transfected MDCK-OATP1B1-UGT1A1-MRP2 cells. Br J Pharmacol 2012; 165:1836-1847. [PMID: 21923755 DOI: 10.1111/j.1476-5381.2011.01672.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE The coordinate activity of hepatic uptake transporters [e.g. organic anion transporting polypeptide 1B1 (OATP1B1)], drug-metabolizing enzymes [e.g. UDP-glucuronosyltransferase 1A1 (UGT1A1)] and efflux pumps (e.g. MRP2) is a crucial determinant of drug disposition. However, limited data are available on transport of drugs (e.g. ezetimibe, etoposide) and their glucuronidated metabolites by human MRP2 in intact cell systems. EXPERIMENTAL APPROACH Using monolayers of newly established triple-transfected MDCK-OATP1B1-UGT1A1-MRP2 cells as well as MDCK control cells, single- (OATP1B1) and double-transfected (OATP1B1-UGT1A1, OATP1B1-MRP2) MDCK cells, we therefore studied intracellular concentrations and transcellular transport after administration of ezetimibe or etoposide to the basal compartment. KEY RESULTS Intracellular accumulation of ezetimibe was significantly lower in MDCK-OATP1B1-UGT1A1-MRP2 triple-transfected cells compared with all other cell lines. Considerably higher amounts of ezetimibe glucuronide were found in the apical compartment of MDCK-OATP1B1-UGT1A1-MRP2 monolayers compared with all other cell lines. Using HEK cells, etoposide was identified as a substrate of OATP1B1. Intracellular concentrations of etoposide equivalents (i.e. parent compound plus metabolites) were affected only to a minor extent by the absence or presence of OATP1B1/UGT1A1/MRP2. In contrast, apical accumulation of etoposide equivalents was significantly higher in monolayers of both cell lines expressing MRP2 (MDCK-OATP1B1-MRP2, MDCK-OATP1B1-UGT1A1-MRP2) compared with the single-transfected (OATP1B1) and the control cell line. CONCLUSIONS AND IMPLICATIONS Ezetimibe glucuronide is a substrate of human MRP2. Moreover, etoposide and possibly also its glucuronide are substrates of MRP2. These data demonstrate the functional interplay between transporter-mediated uptake, phase II metabolism and export by hepatic proteins involved in drug disposition.
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Affiliation(s)
- C Fahrmayr
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - J König
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - D Auge
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - M Mieth
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - M F Fromm
- Institute of Experimental and Clinical Pharmacology and Toxicology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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10
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Expression Profile of Drug and Nutrient Absorption Related Genes in Madin-Darby Canine Kidney (MDCK) Cells Grown under Differentiation Conditions. Pharmaceutics 2012; 4:314-33. [PMID: 24300234 PMCID: PMC3834914 DOI: 10.3390/pharmaceutics4020314] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Revised: 05/15/2012] [Accepted: 06/06/2012] [Indexed: 11/17/2022] Open
Abstract
The expression levels of genes involved in drug and nutrient absorption were evaluated in the Madin-Darby Canine Kidney (MDCK) in vitro drug absorption model. MDCK cells were grown on plastic surfaces (for 3 days) or on Transwell® membranes (for 3, 5, 7, and 9 days). The expression profile of genes including ABC transporters, SLC transporters, and cytochrome P450 (CYP) enzymes was determined using the Affymetrix® Canine GeneChip®. Expression of genes whose probe sets passed a stringent confirmation process was examined. Expression of a few transporter (MDR1, PEPT1 and PEPT2) genes in MDCK cells was confirmed by RT-PCR. The overall gene expression profile was strongly influenced by the type of support the cells were grown on. After 3 days of growth, expression of 28% of the genes was statistically different (1.5-fold cutoff, p < 0.05) between the cells grown on plastic and Transwell® membranes. When cells were differentiated on Transwell® membranes, large changes in gene expression profile were observed during the early stages, which then stabilized after 5–7 days. Only a small number of genes encoding drug absorption related SLC, ABC, and CYP were detected in MDCK cells, and most of them exhibited low hybridization signals. Results from this study provide valuable reference information on endogenous gene expression in MDCK cells that could assist in design of drug-transporter and/or drug-enzyme interaction studies, and help interpret the contributions of various transporters and metabolic enzymes in studies with MDCK cells.
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An G, Morris ME. The sulfated conjugate of biochanin A is a substrate of breast cancer resistant protein (ABCG2). Biopharm Drug Dispos 2011; 32:446-57. [DOI: 10.1002/bdd.772] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 06/26/2011] [Accepted: 07/25/2011] [Indexed: 01/09/2023]
Affiliation(s)
- Guohua An
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences; University at Buffalo, State University of New York; Amherst; NY; 14260; USA
| | - Marilyn E. Morris
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences; University at Buffalo, State University of New York; Amherst; NY; 14260; USA
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Fan Y, Rodriguez-Proteau R. Ketoconazole and the modulation of multidrug resistance-mediated transport in Caco-2 and MDCKII-MDR1 drug transport models. Xenobiotica 2008; 38:107-29. [DOI: 10.1080/00498250701744625] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Zhang H, Li Y, Fan Y, Wu J, Zhao B, Guan Y, Chien S, Wang N. Klotho is a target gene of PPAR-gamma. Kidney Int 2008; 74:732-9. [PMID: 18547997 DOI: 10.1038/ki.2008.244] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Klotho is an anti-aging gene whose expression is regulated by many stimuli. Here we examined the transcriptional regulation of the klotho gene by peroxisome proliferator-activated receptor-gamma (PPAR-gamma). The PPAR-gamma agonists thiazolidinediones increased both klotho mRNA and protein expression in HEK293 cells and several renal epithelial cell lines. The induction was blocked by PPAR-gamma antagonists or small-interfering RNA-mediated gene silencing of PPAR-gamma, suggesting a PPAR-gamma-dependent mechanism. Chromatin immuno-precipitation and gel shift assays found a noncanonical PPAR-responsive element within the 5'-flanking region of the human klotho gene with promoter-reporter assays further confirming transcriptional functionality. Moreover, thiazolidinediones or adenovirus-mediated overexpression of PPAR-gamma increased klotho expression in mouse kidneys while renal klotho expression was attenuated in mice treated with PPAR-gamma antagonists. These results demonstrate that klotho is a target gene of PPAR-gamma.
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Affiliation(s)
- Hong Zhang
- Institute of Cardiovascular Sciences, Peking University Health Science Center, Beijing, China
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Abstract
Models predictive of intestinal drug absorption are important in drug development to identify compounds with promising biopharmaceutical properties. Since permeability is a factor affecting absorption, cell culture models (e.g., Caco-2, MDCK) have been developed to predict drug transport from the intestinal lumen into the bloodstream. The differences as to how the assays are performed, along with heterogeneity of the cell lines, have lead to different permeability values for the same drug. Transport and metabolic properties of cultured cells can vary due to culture conditions, seeding density, passage number, confluency, filter support, monolayer age, and stage of differentiation. During the transport experiment, cell absorption properties can change due to the composition and pH of the transport buffer, solute concentration and solubility, temperature, additives and/or cosolvents, agitation, sampling schedule, sink conditions, and analytical methods. Such variability within a laboratory can be avoided by characterizing a cell culture method and setting acceptance criteria in terms of monolayer integrity, passive transport, and active transport. The repeated evaluation of reference compounds will then facilitate intra-laboratory comparisons.
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Affiliation(s)
- Donna A Volpe
- Division of Product Quality Research, Life Sciences Bldg. 64, 10903 New Hampshire Ave., Silver Spring, Maryland 20993-0002, USA.
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Franco R, Panayiotidis MI, Cidlowski JA. Glutathione depletion is necessary for apoptosis in lymphoid cells independent of reactive oxygen species formation. J Biol Chem 2007; 282:30452-65. [PMID: 17724027 PMCID: PMC2267748 DOI: 10.1074/jbc.m703091200] [Citation(s) in RCA: 212] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Changes in the intracellular redox environment of cells have been reported to be critical for the activation of apoptotic enzymes and the progression of programmed cell death. Glutathione (GSH) depletion is an early hallmark observed in apoptosis, and we have demonstrated that GSH efflux during death receptor-mediated apoptosis occurs via a GSH transporter. We now evaluate the relationship between GSH depletion, the generation of reactive oxygen species (ROS), and the progression of apoptosis. Simultaneous single cell analysis of changes in GSH content and ROS formation by multiparametric FACS revealed that loss of intracellular GSH was paralleled by the generation of different ROS including hydrogen peroxide, superoxide anion, hydroxyl radical, and lipid peroxides. However, inhibition of ROS formation by a variety of antioxidants showed that GSH loss was independent from the generation of ROS. Furthermore, GSH depletion was observed to be necessary for ROS generation. Interestingly, high extracellular thiol concentration (GSH and N-acetyl-cysteine) inhibited apoptosis, whereas, inhibition of ROS generation by other non-thiol antioxidants was ineffective in preventing cell death. Finally, GSH depletion was shown to be a necessary for the progression of apoptosis activated by both extrinsic and intrinsic signaling pathways. These results document a necessary and critical role for GSH loss in apoptosis and clearly uncouple for the first time GSH depletion from ROS formation.
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Affiliation(s)
- Rodrigo Franco
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
| | | | - John A. Cidlowski
- From the Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709
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Franco R, Schoneveld OJ, Pappa A, Panayiotidis MI. The central role of glutathione in the pathophysiology of human diseases. Arch Physiol Biochem 2007; 113:234-58. [PMID: 18158646 DOI: 10.1080/13813450701661198] [Citation(s) in RCA: 358] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Reduced glutathione (L-gamma-glutamyl-L-cysteinyl-glycine, GSH) is the prevalent low-molecular-weight thiol in mammalian cells. It is formed in a two-step enzymatic process including, first, the formation of gamma-glutamylcysteine from glutamate and cysteine, by the activity of the gamma-glutamylcysteine synthetase; and second, the formation of GSH by the activity of GSH synthetase which uses gamma-glutamylcysteine and glycine as substrates. While its synthesis and metabolism occur intracellularly, its catabolism occurs extracellularly by a series of enzymatic and plasma membrane transport steps. Glutathione metabolism and transport participates in many cellular reactions including: antioxidant defense of the cell, drug detoxification and cell signaling (involved in the regulation of gene expression, apoptosis and cell proliferation). Alterations in its concentration have also been demonstrated to be a common feature of many pathological conditions including diabetes, cancer, AIDS, neurodegenerative and liver diseases. Additionally, GSH catabolism has been recently reported to modulate redox-sensitive components of signal transduction cascades. In this manuscript, we review the current state of knowledge on the role of GSH in the pathogenesis of human diseases with the aim to underscore its relevance in translational research for future therapeutic treatment design.
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Affiliation(s)
- R Franco
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA
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Schlatter P, Gutmann H, Drewe J. Primary porcine proximal tubular cells as a model for transepithelial drug transport in human kidney. Eur J Pharm Sci 2006; 28:141-54. [PMID: 16510270 DOI: 10.1016/j.ejps.2006.01.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2005] [Revised: 12/20/2005] [Accepted: 01/18/2006] [Indexed: 01/11/2023]
Abstract
BACKGROUND Kidney proximal tubular cells play a major role in the transport of endogenous and exogenous compounds. A multitude of different transporters are expressed starting with multidrug ABC transporters (e.g. abcb1, abcc1-6), slc22a6-8 (organic anion transporters) and slc22a1-3 (organic cation transporters). For transport studies of renal drug transport, cell lines like MDCK and LLC-PK1 are often used to overexpress and study one or two transporters, such as abcb1 or abcc1-6. However, the use is limited since under physiological conditions xenobiotics are transported through different transporters at the same time. Therefore, a primary in vitro model expressing functionally different transporters simultaneously, as it is the case in vivo, would be of great benefit. METHODS Primary proximal tubular cells were isolated from porcine kidney. Cells were cultured under selective culturing conditions leading to specific growth of primary proximal tubular cells. Expression of important proximal transporters was checked at mRNA level with RT-PCR, at protein level with immunocytochemistry and functionally by transport and uptake assays. RESULTS A model of primary proximal tubular cells was established expressing the most important transporters: abcb1, abcc1, abcc2, slc22a8, slco1a2, slc15a1, slc5a2 and slc4a4. In freshly isolated cells, slc22a1 and slc22a6 were expressed, but were down-regulated in culture. Abcb1, abcc1, abcc2 and slc4a4 were detected at protein level with immunostaining. Functional activity was confirmed for abcb1, abcc1/2, slc22a8, slc15a1/2 and slc5a1/2. The tightness of the monolayers of this model was better than in previously established in vitro models. CONCLUSION This primary cell culture model might be an interesting tool to investigate proximal tubular transport and to predict toxicity and drug interactions since it expresses functionally several transporters simultaneously.
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Affiliation(s)
- Philipp Schlatter
- Department of Clinical Pharmacology and Toxicology, University Hospital, Basel, Switzerland
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Young AM, Audus KL, Proudfoot J, Yazdanian M. Tetrazole compounds: The effect of structure and pH on Caco-2 cell permeability. J Pharm Sci 2006; 95:717-25. [PMID: 16498570 DOI: 10.1002/jps.20526] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A tetrazole ring is often used in drug discovery as a replacement for the carboxylic acid group. Previous work indicates that compounds containing a tetrazole moiety show asymmetric permeability in Caco-2 cells characteristic of an efflux transporter substrate. The aim of this study is to determine which transporters are responsible for polarization of transport of tetrazole-containing compounds in Caco-2 cells. Results indicate that only select compounds with tetrazole moieties display asymmetric transport. Three compounds (two commercial drug products and one druglike structure) were selected for further studies. Losartan appears to be primarily a P-glycoprotein (P-gp) substrate, as previously reported, but MRP inhibitors such as MK-571 and rifampicin also affect the difference between apical to basolateral and basolateral to apical transport. Pemirolast and phenyltetrazole derivative C are sensitive to P-gp inhibition, but transport seems to be mediated by one or more of the MRP family of transporters. Additionally, lowering the pH from 7.4 to 4.0 eliminates the polarization of permeability in Caco-2 cells. These studies indicate that some tetrazole compounds are susceptible to efflux, therefore caution should be used when choosing an appropriate functional group to replace carboxylic acids when synthesizing a drug candidate.
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Affiliation(s)
- Amber M Young
- Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas, USA
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Aleo MF, Morandini F, Bettoni F, Giuliani R, Rovetta F, Steimberg N, Apostoli P, Parrinello G, Mazzoleni G. Endogenous thiols and MRP transporters contribute to Hg2+ efflux in HgCl2-treated tubular MDCK cells. Toxicology 2005; 206:137-51. [PMID: 15590114 DOI: 10.1016/j.tox.2004.07.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2004] [Revised: 07/07/2004] [Accepted: 07/12/2004] [Indexed: 11/28/2022]
Abstract
Tubular epithelium represents the primary target of mercuric ions (Hg(2+)) nephrotoxicity. Although widely investigated, the mechanisms of Hg(2+) cell uptake, accumulation and excretion all along the nephron remain largely unknown. In the present study, native distal tubular-derived Madin-Darby canine kidney (MDCK) cells exposed to subcytotoxic (micromolar) HgCl(2) concentrations were used for investigating specific mechanisms involved in the tubular response to toxic metals. Inductively coupled plasma-mass spectrometry (ICP-MS) was firstly used for assessing HgCl(2) solubility and then for quantifying Hg(2+) cell uptake. Exposed to HgCl(2), MDCK cells showed a rapid, but transient, Hg(2+) accumulation. The metallic cation was found to affect cell density and morphology, being these effects related to the dose and the time of exposure. In parallel, an Hg(2+)-induced up-regulation of endogenous MRP1 and MRP2 export pumps, a significant HgCl(2)-dependent induction of protective cellular thiols and an increase in the glutathione conjugates metabolism were also observed. The functional suppression of MRPs activity, obtained by MK-571 treatment, increased the Hg(2+) cell content and the sensitivity of MDCK cells to HgCl(2). Our results demonstrate that, in MDCK cells, inorganic Hg(2+) promotes the activation of specific detoxifying pathways that may, at least partly, depend on the activity of MRP transporters.
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Affiliation(s)
- Maria Francesca Aleo
- Unit of Biochemistry, Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, viale Europa, 11, 25123 Brescia, Italy.
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Mita S, Suzuki H, Akita H, Stieger B, Meier PJ, Hofmann AF, Sugiyama Y. Vectorial transport of bile salts across MDCK cells expressing both rat Na+-taurocholate cotransporting polypeptide and rat bile salt export pump. Am J Physiol Gastrointest Liver Physiol 2005; 288:G159-67. [PMID: 15297262 DOI: 10.1152/ajpgi.00360.2003] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Bile salts are predominantly taken up by hepatocytes via the basolateral Na(+)-taurocholate cotransporting polypeptide (NTCP/SLC10A1) and secreted into the bile by the bile salt export pump (BSEP/ABCB11). In the present study, we transfected rat Ntcp and rat Bsep into polarized Madin-Darby canine kidney cells and characterized the transport properties of these cells for eight bile salts. Immunohistochemical staining demonstrated that Ntcp was expressed at the basolateral domains, whereas Bsep was expressed at the apical domains. Basal-to-apical transport of taurocholate across the monolayer expressing only Ntcp and that coexpressing Ntcp/Bsep was observed, whereas the flux across the monolayer of control and Bsep-expressing cells was symmetrical. Basal-to-apical transport of taurocholate across Ntcp/Bsep-coexpressing monolayers was significantly higher than that across monolayers expressing only Ntcp. Kinetic analysis of this vectorial transport of taurocholate gave an apparent K(m) value of 13.9 +/- 4.7 microM for cells expressing Ntcp alone, which is comparable with 22.2 +/- 4.5 microM for cells expressing both Ntcp and Bsep and V(max) values of 15.8 +/- 4.2 and 60.8 +/- 9.0 pmol.min(-1).mg protein(-1) for Ntcp alone and Ntcp and Bsep-coexpressing cells, respectively. Transcellular transport of cholate, glycocholate, taurochenodeoxycholate, chenodeoxycholate, glycochenodeoxycholate, tauroursodeoxycholate, ursodeoxycholate, and glycoursodeoxycholate, but not that of lithocholate was also observed across the double transfectant. This double-expressing system can be used as a model to clarify vectorial transport of bile salts across hepatocytes under physiological conditions.
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Affiliation(s)
- Sachiko Mita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
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Su Y, Lee SH, Sinko PJ. Practical Aspects of Transporter Model Systems: A Case Study Involving SQV. Drug Metab Rev 2004; 36:377-89. [PMID: 15237860 DOI: 10.1081/dmr-120037570] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In this case study, in vitro and in vivo data were provided for saquinavir (SQV) showing that drug transporters play a significant role in the absorption and disposition of drugs. This article is focused on the more practical points with a technical emphasis. Currently many in vitro and in vivo experimental models have been developed to investigate drug transporter interactions for the prediction of how transporters may influence the pharmacokinetic behavior of drugs. In this review, the successful application, limitations and challenges of these models are emphasized.
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Affiliation(s)
- Yaming Su
- Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA
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