1
|
Ahmad E, Ali A, Nimisha, Kumar Sharma A, Ahmed F, Mehdi Dar G, Mohan Singh A, Apurva, Kumar A, Athar A, Parveen F, Mahajan B, Singh Saluja S. Molecular approaches in cancer. Clin Chim Acta 2022; 537:60-73. [DOI: https:/doi.org/10.1016/j.cca.2022.09.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
|
2
|
Ahmad E, Ali A, Nimisha, Kumar Sharma A, Ahmed F, Mehdi Dar G, Mohan Singh A, Apurva, Kumar A, Athar A, Parveen F, Mahajan B, Singh Saluja S. Molecular approaches in cancer. Clin Chim Acta 2022; 537:60-73. [DOI: 10.1016/j.cca.2022.09.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 09/28/2022] [Accepted: 09/28/2022] [Indexed: 11/03/2022]
|
3
|
Marin JJG, Monte MJ, Macias RIR, Romero MR, Herraez E, Asensio M, Ortiz-Rivero S, Cives-Losada C, Di Giacomo S, Gonzalez-Gallego J, Mauriz JL, Efferth T, Briz O. Expression of Chemoresistance-Associated ABC Proteins in Hepatobiliary, Pancreatic and Gastrointestinal Cancers. Cancers (Basel) 2022; 14:cancers14143524. [PMID: 35884584 PMCID: PMC9320734 DOI: 10.3390/cancers14143524] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/14/2022] [Accepted: 07/14/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary One-third of the approximately 10 million deaths yearly caused by cancer worldwide are due to hepatobiliary, pancreatic, and gastrointestinal tumors. One primary reason for this high mortality is the lack of response of these cancers to pharmacological treatment. More than 100 genes have been identified as responsible for seven mechanisms of chemoresistance, but only a few of them play a critical role. These include ABC proteins (mainly MDR1, MRP1-6, and BCRP), whose expression pattern greatly determines the individual sensitivity of each tumor to pharmacotherapy. Abstract Hepatobiliary, pancreatic, and gastrointestinal cancers account for 36% of the ten million deaths caused by cancer worldwide every year. The two main reasons for this high mortality are their late diagnosis and their high refractoriness to pharmacological treatments, regardless of whether these are based on classical chemotherapeutic agents, targeted drugs, or newer immunomodulators. Mechanisms of chemoresistance (MOC) defining the multidrug resistance (MDR) phenotype of each tumor depend on the synergic function of proteins encoded by more than one hundred genes classified into seven groups (MOC1-7). Among them, the efflux of active agents from cancer cells across the plasma membrane caused by members of the superfamily of ATP-binding cassette (ABC) proteins (MOC-1b) plays a crucial role in determining tumor MDR. Although seven families of human ABC proteins are known, only a few pumps (mainly MDR1, MRP1-6, and BCRP) have been associated with reducing drug content and hence inducing chemoresistance in hepatobiliary, pancreatic, and gastrointestinal cancer cells. The present descriptive review, which compiles the updated information on the expression of these ABC proteins, will be helpful because there is still some confusion on the actual relevance of these pumps in response to pharmacological regimens currently used in treating these cancers. Moreover, we aim to define the MOC pattern on a tumor-by-tumor basis, even in a dynamic way, because it can vary during tumor progression and in response to chemotherapy. This information is indispensable for developing novel strategies for sensitization.
Collapse
Affiliation(s)
- Jose J. G. Marin
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
- Correspondence: (J.J.G.M.); (O.B.); Tel.: +34-663182872 (J.J.G.M.); +34-663056225 (O.B.)
| | - Maria J. Monte
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Rocio I. R. Macias
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Marta R. Romero
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Elisa Herraez
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Maitane Asensio
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Sara Ortiz-Rivero
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
| | - Candela Cives-Losada
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
| | - Silvia Di Giacomo
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy;
| | - Javier Gonzalez-Gallego
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
- Institute of Biomedicine (IBIOMED), University of León, Campus of Vegazana s/n, 24071 Leon, Spain
| | - Jose L. Mauriz
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
- Institute of Biomedicine (IBIOMED), University of León, Campus of Vegazana s/n, 24071 Leon, Spain
| | - Thomas Efferth
- Department of Pharmaceutical Biology, Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg University, Staudinger Weg 5, 55128 Mainz, Germany;
| | - Oscar Briz
- Experimental Hepatology and Drug Targeting (HEVEPHARM) Group, University of Salamanca, IBSAL, 37007 Salamanca, Spain; (M.J.M.); (R.I.R.M.); (M.R.R.); (E.H.); (M.A.); (S.O.-R.); (C.C.-L.)
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Institute of Health, 28029 Madrid, Spain; (J.G.-G.); (J.L.M.)
- Correspondence: (J.J.G.M.); (O.B.); Tel.: +34-663182872 (J.J.G.M.); +34-663056225 (O.B.)
| |
Collapse
|
4
|
Zhao X, Li Y, Du K, Wu Y, Liu L, Cui S, Zhang Y, Gao J, Keep RF, Xiang J. Involvement of human and canine MRP1 and MRP4 in benzylpenicillin transport. PLoS One 2019; 14:e0225702. [PMID: 31774876 PMCID: PMC6881026 DOI: 10.1371/journal.pone.0225702] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 11/11/2019] [Indexed: 02/06/2023] Open
Abstract
The blood-brain barrier (BBB) is a dynamic and complex interface between blood and the central nervous system (CNS). It protects the brain by preventing toxic substances from entering the brain but also limits the entry of therapeutic agents. ATP-binding cassette (ABC) efflux transporters are critical for the functional barrier and present a formidable impediment to brain delivery of therapeutic agents including antibiotics. The aim of this study was to investigate the possible involvement of multidrug resistance-associated protein 1 and 4 (MRP1 and MRP4), two ABC transporters, in benzylpenicillin efflux transport using wild-type (WT) MDCKII cells and cells overexpressing those human transporters, as well as non-selective and selective inhibitors. We found that inhibiting MRP1 or MRP4 significantly increased [3H]benzylpenicillin uptake in MDCKII-WT, -MRP1 or -MRP4 cells. Similar results were also found in HepG2 cells, which highly express MRP1 and MRP4, and hCMEC/D3 cells which express MRP1. The results indicate that human and canine MRP1 and MRP4 are involved in benzylpenicillin efflux transport. They could be potential therapeutic targets for improving the efficacy of benzylpenicillin for treating CNS infections since both MRP1 and MRP4 express at human blood-brain barrier.
Collapse
Affiliation(s)
- Xiaofen Zhao
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Yangfang Li
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Kun Du
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Yuqin Wu
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Ling Liu
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Shan Cui
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Yan Zhang
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Jin Gao
- Department of Neonate, Kunming Children’s Hospital, Kunming, China
| | - Richard F. Keep
- Department of Neurosurgery, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| | - Jianming Xiang
- Department of Neurosurgery, University of Michigan Medical School, Ann Arbor, Michigan, United States of America
| |
Collapse
|
5
|
Magnarin M, Rosati A, De Iudicibus S, Bartoli F, Decorti G. Role of ABC Transporters in the BeWo Trophoblast Cell Line. Toxicol Mech Methods 2012; 18:763-9. [PMID: 20020937 DOI: 10.1080/15376510802428591] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
ABSTRACT The transport of doxorubicin and rhodamine 123, substrates of ABC transporters, was evaluated in the BeWo stabilized trophoblast cell line. Both compounds were taken up by BeWo cells, but their intracellular concentrations were highly dependent on temperature, and significantly reduced at 4 degrees C. The P-glycoprotein inhibitors verapamil and PSC833 did not modify the intracellular concentrations of the two substrates, suggesting therefore that, in these cells, the activity of P-glycoprotein is not important. MK571, which inhibits MRPs, was on the contrary effective in increasing rhodamine 123 intracellular concentrations. The efflux of both fluorescent substrates was extremely slow, and slightly reduced by MK571. Finally, a polarized transport of doxorubicin from basal to apical side was evident, although only during the first 60 min of incubation, and was reduced by P-glycoprotein, MRP, and BCRP inhibitors. No MDR1 expression was revealed at the mRNA and protein levels; on the contrary, MRP1 and BCRP were expressed in these cells. In BeWo cells the activity of ABC transporters, and in particular of P-glycoprotein, seems to be extremely limited.
Collapse
Affiliation(s)
- Monica Magnarin
- Department of Biomedical Sciences, University of Trieste, Trieste, Italy
| | | | | | | | | |
Collapse
|
6
|
Qin L, Tam SP, Deeley RG. Effect of Multiple Cysteine Substitutions on the Functionality of Human Multidrug Resistance Protein 1 Expressed in Human Embryonic Kidney 293 Cells: Identification of Residues Essential for Function. Drug Metab Dispos 2012; 40:1403-13. [DOI: 10.1124/dmd.112.044867] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
7
|
Indomethacin and SC236 enhance the cytotoxicity of doxorubicin in human hepatocellular carcinoma cells via inhibiting P-glycoprotein and MRP1 expression. Cancer Lett 2011; 304:90-6. [DOI: 10.1016/j.canlet.2011.01.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 12/25/2010] [Accepted: 01/27/2011] [Indexed: 12/21/2022]
|
8
|
Gu X, Manautou JE. Regulation of hepatic ABCC transporters by xenobiotics and in disease states. Drug Metab Rev 2010; 42:482-538. [PMID: 20233023 DOI: 10.3109/03602531003654915] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The subfamily of ABCC transporters consists of 13 members in mammals, including the multidrug resistance-associated proteins (MRPs), sulfonylurea receptors (SURs), and the cystic fibrosis transmembrane conductance regulator (CFTR). These proteins play roles in chemical detoxification, disposition, and normal cell physiology. ABCC transporters are expressed differentially in the liver and are regulated at the transcription and translation level. Their expression and function are also controlled by post-translational modification and membrane-trafficking events. These processes are tightly regulated. Information about alterations in the expression of hepatobiliary ABCC transporters could provide important insights into the pathogenesis of diseases and disposition of xenobiotics. In this review, we describe the regulation of hepatic ABCC transporters in humans and rodents by a variety of xenobiotics, under disease states and in genetically modified animal models deficient in transcription factors, transporters, and cell-signaling molecules.
Collapse
Affiliation(s)
- Xinsheng Gu
- Department of Pharmaceutical Sciences, University of Connecticut, Storrs, 06269, USA
| | | |
Collapse
|
9
|
Prouillac C, Lecoeur S. The Role of the Placenta in Fetal Exposure to Xenobiotics: Importance of Membrane Transporters and Human Models for Transfer Studies. Drug Metab Dispos 2010; 38:1623-35. [DOI: 10.1124/dmd.110.033571] [Citation(s) in RCA: 143] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
10
|
Nagashige M, Ushigome F, Koyabu N, Hirata K, Kawabuchi M, Hirakawa T, Satoh S, Tsukimori K, Nakano H, Uchiumi T, Kuwano M, Ohtani H, Sawada Y. Basal Membrane Localization of MRP1 in Human Placental Trophoblast. Placenta 2003; 24:951-8. [PMID: 14580377 DOI: 10.1016/s0143-4004(03)00170-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The placental trophoblast is considered to act as a barrier between mother and fetus, mediating the exchange of various materials across the placenta. ATP-binding cassette (ABC) transporters such as P-glycoprotein (P-gp) and multidrug-resistance protein (MRP) are expressed in the placenta and function as efflux transport systems for xenobiotics. In the present study, we aimed to determine the localization of MRP1 in the human placenta in comparison with that of P-gp. Western blotting analysis with human placental membrane vesicles indicated that P-gp and MRP1 are localized on the brush-border membranes and basal membranes, respectively. Immunohistochemical analysis with human normal full-term placenta showed that anti-P-gp monoclonal antibody F4 stained the brush-border side of the trophoblast cells, whereas anti-MRP1 monoclonal antibody MRPr1 stained the basal side. These results confirm that P-gp and MRP1 are located on the brush-border membranes and basal membranes, respectively, of human full-term placental trophoblast. MRP1 was also detected on the abluminal side of blood vessels in the villi. Accordingly, MRP1 may play a role distinct from that of P-gp, which is considered to restrict the influx of xenobiotics into the fetus.
Collapse
Affiliation(s)
- M Nagashige
- Department of Medico-Pharmaceutical Sciences, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, 812-8582 Fukuoka, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
The use of pharmaceuticals during pregnancy is often a necessity for the health of the mother. Until recently, the placenta was viewed as a passive organ through which molecules are passed indiscriminately between mother and fetus. In reality, the placenta contains a plethora of transporters, some of which appear to be specifically dedicated to removal of xenobiotics and toxic endogenous compounds. Drug efflux transporters such as P-glycoprotein (P-gp), several multidrug resistant associated proteins (MRPs) and breast cancer resistant protein (BCRP) may provide mechanisms that protect the developing fetus. Bile acid transporters may also play a role in exporting compounds back into the maternal compartment. Steroid hormones directly influence the level of expression and function in some of these transporters. Investigating the link between the hormones of pregnancy and these drug efflux transporters is one possible key in developing strategies to deliver drugs to the mother with minimal fetal risk.
Collapse
Affiliation(s)
- Amber M Young
- Department of Pharmaceutical Chemistry, The University of Kansas, 2095 Constant Avenue, Lawrence, KS 66047, USA
| | | | | |
Collapse
|
12
|
Bandi N, Kompella UB. Budesonide reduces multidrug resistance-associated protein 1 expression in an airway epithelial cell line (Calu-1). Eur J Pharmacol 2002; 437:9-17. [PMID: 11864633 DOI: 10.1016/s0014-2999(02)01267-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The objective of this study was to determine the expression and activity of multidrug resistance-associated protein (MRP1) in a human airway epithelial cell line (Calu-1) and to further assess whether budesonide, a potent antiasthma corticosteroid, alters the expression and activity of MRP1 in these cells. Reverse transcriptase polymerase chain reaction (RT-PCR) and the Western blot analysis demonstrated the MRP1 mRNA and MRP1 protein in Calu-1 cells. Indomethacin, probenecid, and verapamil significantly enhanced the fluorescein accumulation and reduced the fluorescein efflux, consistent with the MRP1 activity in the Calu-1 cells. Following 14-day budesonide treatment, fluorescein accumulation increased and fluorescein efflux decreased, consistent with the inhibition of MRP1 activity by budesonide. At a concentration (10 microM) devoid of cytotoxicity, budesonide treatment decreased MRP1 mRNA and MRP1 protein expression in Calu-1 cells by 38% and 42%, respectively. In addition, budesonide (10 microM) enhanced the sensitivity of the MRP1 overexpressing COR-L23R cells to vincristine, suggesting the chemosensitizing effect of budesonide. Thus, budesonide inhibits MRP1 expression and may be useful as a chemosensitizer in tumor chemotherapy.
Collapse
Affiliation(s)
- Nagesh Bandi
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE 68198-6025, USA
| | | |
Collapse
|
13
|
Aukunuru JV, Sunkara G, Bandi N, Thoreson WB, Kompella UB. Expression of multidrug resistance-associated protein (MRP) in human retinal pigment epithelial cells and its interaction with BAPSG, a novel aldose reductase inhibitor. Pharm Res 2001. [PMID: 11465409 DOI: 10.1023/a: 1011060705599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE The objective of this study was to determine the expression and activity of multidrug resistance-associated protein (MRP) in the retinal pigment epithelial (RPE) cells and to further assess whether BAPSG, a novel anionic aldose reductase inhibitor, interacts with MRP. METHODS Functional and biochemical evidence for MRP was obtained in a human retinal pigment epithelial (ARPE-19) cell line and primary cultures of human retinal pigment epithelial (HRPE) cells. Fluorescein accumulation and efflux in the presence and absence of MRP inhibitors was used to obtain functional evidence for MRP. Western blots and RT-PCR were used to obtain biochemical evidence for MRP1. The influence of MRP inhibitors on BAPSG accumulation and efflux in ARPE-19 cells was determined to understand its interaction with MRP. RESULTS MRP inhibitors increased fluorescein accumulation and reduced efflux in RPE cells. Both cell types exhibited a 190-kDa western blot band corresponding to MRP1 protein and a 287 bp RT-PCR band corresponding to MRP1 mRNA. MRP inhibitors reduced BAPSG efflux and increased its accumulation in ARPE-19 cells. CONCLUSIONS MRP is functionally and biochemically active in human RPE cells. Anionic BAPSG is a likely substrate for MRP.
Collapse
Affiliation(s)
- J V Aukunuru
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha 68198-6025, USA
| | | | | | | | | |
Collapse
|
14
|
Lee TK, Hammond CL, Ballatori N. Intracellular glutathione regulates taurocholate transport in HepG2 cells. Toxicol Appl Pharmacol 2001; 174:207-15. [PMID: 11485381 DOI: 10.1006/taap.2001.9208] [Citation(s) in RCA: 170] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The hepatic organic anion transporter 1, Oatp1, was recently demonstrated to function as a GSH exchanger, indicating that hepatic uptake of drugs and xenobiotics may be sensitive to intracellular GSH levels. The present study characterized taurocholate uptake and efflux mechanisms in HepG2 cells and the effects of intracellular GSH on these transport processes. Taurocholate uptake into HepG2 cells was Na(+)-independent, saturable ( K(m) = 82 +/- 16 microM), and was cis-inhibited by bromosulfophthalein and some bile acids. Intracellular GSH depletion inhibited 3H-taurocholate uptake, and, conversely, the release of GSH from HepG2 cells was stimulated in the presence of extracellular taurocholate and other bile acids, consistent with a role for intracellular GSH in stimulating organic anion uptake. Interestingly, efflux of 3H-taurocholate from HepG2 cells was also sensitive to intracellular GSH concentration: efflux was inhibited in cells with lower intracellular GSH and stimulated in cells with higher GSH. RT-PCR analysis revealed that OATP-A, OATP-D, OATP-E, OATP-8, MRP1, MRP2, and MRP3 are expressed in HepG2 cells but that their expression is not altered by the maneuvers used to lower or raise intracellular GSH. These results provide direct evidence that intracellular GSH levels modulate both uptake and efflux of taurocholate and suggest that GSH plays a regulatory role in the hepatobiliary transport of potentially toxic organic compounds.
Collapse
Affiliation(s)
- T K Lee
- Department of Environmental Medicine, University of Rochester School of Medicine, Rochester, New York, 14642, USA
| | | | | |
Collapse
|
15
|
Aukunuru JV, Sunkara G, Bandi N, Thoreson WB, Kompella UB. Expression of multidrug resistance-associated protein (MRP) in human retinal pigment epithelial cells and its interaction with BAPSG, a novel aldose reductase inhibitor. Pharm Res 2001; 18:565-72. [PMID: 11465409 DOI: 10.1023/a:1011060705599] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE The objective of this study was to determine the expression and activity of multidrug resistance-associated protein (MRP) in the retinal pigment epithelial (RPE) cells and to further assess whether BAPSG, a novel anionic aldose reductase inhibitor, interacts with MRP. METHODS Functional and biochemical evidence for MRP was obtained in a human retinal pigment epithelial (ARPE-19) cell line and primary cultures of human retinal pigment epithelial (HRPE) cells. Fluorescein accumulation and efflux in the presence and absence of MRP inhibitors was used to obtain functional evidence for MRP. Western blots and RT-PCR were used to obtain biochemical evidence for MRP1. The influence of MRP inhibitors on BAPSG accumulation and efflux in ARPE-19 cells was determined to understand its interaction with MRP. RESULTS MRP inhibitors increased fluorescein accumulation and reduced efflux in RPE cells. Both cell types exhibited a 190-kDa western blot band corresponding to MRP1 protein and a 287 bp RT-PCR band corresponding to MRP1 mRNA. MRP inhibitors reduced BAPSG efflux and increased its accumulation in ARPE-19 cells. CONCLUSIONS MRP is functionally and biochemically active in human RPE cells. Anionic BAPSG is a likely substrate for MRP.
Collapse
Affiliation(s)
- J V Aukunuru
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha 68198-6025, USA
| | | | | | | | | |
Collapse
|