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Korbecki J, Rębacz-Maron E, Kupnicka P, Chlubek D, Baranowska-Bosiacka I. Synthesis and Significance of Arachidonic Acid, a Substrate for Cyclooxygenases, Lipoxygenases, and Cytochrome P450 Pathways in the Tumorigenesis of Glioblastoma Multiforme, Including a Pan-Cancer Comparative Analysis. Cancers (Basel) 2023; 15:cancers15030946. [PMID: 36765904 PMCID: PMC9913267 DOI: 10.3390/cancers15030946] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/25/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Glioblastoma multiforme (GBM) is one of the most aggressive gliomas. New and more effective therapeutic approaches are being sought based on studies of the various mechanisms of GBM tumorigenesis, including the synthesis and metabolism of arachidonic acid (ARA), an omega-6 polyunsaturated fatty acid (PUFA). PubMed, GEPIA, and the transcriptomics analysis carried out by Seifert et al. were used in writing this paper. In this paper, we discuss in detail the biosynthesis of this acid in GBM tumors, with a special focus on certain enzymes: fatty acid desaturase (FADS)1, FADS2, and elongation of long-chain fatty acids family member 5 (ELOVL5). We also discuss ARA metabolism, particularly its release from cell membrane phospholipids by phospholipase A2 (cPLA2, iPLA2, and sPLA2) and its processing by cyclooxygenases (COX-1 and COX-2), lipoxygenases (5-LOX, 12-LOX, 15-LOX-1, and 15-LOX-2), and cytochrome P450. Next, we discuss the significance of lipid mediators synthesized from ARA in GBM cancer processes, including prostaglandins (PGE2, PGD2, and 15-deoxy-Δ12,14-PGJ2 (15d-PGJ2)), thromboxane A2 (TxA2), oxo-eicosatetraenoic acids, leukotrienes (LTB4, LTC4, LTD4, and LTE4), lipoxins, and many others. These lipid mediators can increase the proliferation of GBM cancer cells, cause angiogenesis, inhibit the anti-tumor response of the immune system, and be responsible for resistance to treatment.
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Affiliation(s)
- Jan Korbecki
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Ewa Rębacz-Maron
- Department of Ecology and Anthropology, Institute of Biology, University of Szczecin, Wąska 13, 71-415 Szczecin, Poland
| | - Patrycja Kupnicka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Dariusz Chlubek
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University in Szczecin, Powstańców Wlkp. 72, 70-111 Szczecin, Poland
- Correspondence: ; Tel.: +48-914-661-515
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Haeggström JZ, Newcomer ME. Structures of Leukotriene Biosynthetic Enzymes and Development of New Therapeutics. Annu Rev Pharmacol Toxicol 2023; 63:407-428. [PMID: 36130059 DOI: 10.1146/annurev-pharmtox-051921-085014] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Leukotrienes are potent immune-regulating lipid mediators with patho-genic roles in inflammatory and allergic diseases, particularly asthma. These autacoids also contribute to low-grade inflammation, a hallmark of cardiovascular, neurodegenerative, metabolic, and tumor diseases. Biosynthesis of leukotrienes involves release and oxidative metabolism of arachidonic acid and proceeds via a set of cytosolic and integral membrane enzymes that are typically expressed by cells of the innate immune system. In activated cells, these enzymes traffic and assemble at the endoplasmic and perinuclear membrane, together comprising a biosynthetic complex. Here we describe recent advances in our molecular understanding of the protein components of the leukotriene-synthesizing enzyme machinery and also briefly touch upon the leukotriene receptors. Moreover, we discuss emerging opportunities for pharmacological intervention and development of new therapeutics.
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Affiliation(s)
- Jesper Z Haeggström
- Department of Medical Biochemistry and Biophysics, Division of Chemistry 2, Karolinska Institutet, Stockholm, Sweden;
| | - Marcia E Newcomer
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA;
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3
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Khan HA, Jabeen I. Combined Machine Learning and GRID-Independent Molecular Descriptor (GRIND) Models to Probe the Activity Profiles of 5-Lipoxygenase Activating Protein Inhibitors. Front Pharmacol 2022; 13:825741. [PMID: 35300294 PMCID: PMC8921698 DOI: 10.3389/fphar.2022.825741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/03/2022] [Indexed: 01/31/2023] Open
Abstract
Leukotrienes (LTs) are pro-inflammatory lipid mediators derived from arachidonic acid (AA), and their high production has been reported in multiple allergic, autoimmune, and cardiovascular disorders. The biological synthesis of leukotrienes is instigated by transfer of AA to 5-lipoxygenase (5-LO) via the 5-lipoxygenase-activating protein (FLAP). Suppression of FLAP can inhibit LT production at the earliest level, providing relief to patients requiring anti-leukotriene therapy. Over the last 3 decades, several FLAP modulators have been synthesized and pharmacologically tested, but none of them could be able to reach the market. Therefore, it is highly desirable to unveil the structural requirement of FLAP modulators. Here, in this study, supervised machine learning techniques and molecular modeling strategies are adapted to vaticinate the important 2D and 3D anti-inflammatory properties of structurally diverse FLAP inhibitors, respectively. For this purpose, multiple machine learning classification models have been developed to reveal the most relevant 2D features. Furthermore, to probe the 3D molecular basis of interaction of diverse anti-inflammatory compounds with FLAP, molecular docking studies were executed. By using the most probable binding poses from docking studies, the GRIND model was developed, which indicated the positive contribution of four hydrophobic, two hydrogen bond acceptor, and two shape-based features at certain distances from each other towards the inhibitory potency of FLAP modulators. Collectively, this study sheds light on important two-dimensional and three-dimensional structural requirements of FLAP modulators that can potentially guide the development of more potent chemotypes for the treatment of inflammatory disorders.
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Affiliation(s)
- Hafiza Aliza Khan
- Research Centre for Modelling and Simulation (RCMS), NUST Interdisciplinary Cluster for Higher Education (NICHE), National University of Sciences and Technology (NUST), Islamabad, Pakistan
| | - Ishrat Jabeen
- Research Centre for Modelling and Simulation (RCMS), NUST Interdisciplinary Cluster for Higher Education (NICHE), National University of Sciences and Technology (NUST), Islamabad, Pakistan
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4
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Kroll T, Prescher M, Smits SHJ, Schmitt L. Structure and Function of Hepatobiliary ATP Binding Cassette Transporters. Chem Rev 2020; 121:5240-5288. [PMID: 33201677 DOI: 10.1021/acs.chemrev.0c00659] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The liver is beyond any doubt the most important metabolic organ of the human body. This function requires an intensive crosstalk within liver cellular structures, but also with other organs. Membrane transport proteins are therefore of upmost importance as they represent the sensors and mediators that shuttle signals from outside to the inside of liver cells and/or vice versa. In this review, we summarize the known literature of liver transport proteins with a clear emphasis on functional and structural information on ATP binding cassette (ABC) transporters, which are expressed in the human liver. These primary active membrane transporters form one of the largest families of membrane proteins. In the liver, they play an essential role in for example bile formation or xenobiotic export. Our review provides a state of the art and comprehensive summary of the current knowledge of hepatobiliary ABC transporters. Clearly, our knowledge has improved with a breath-taking speed over the last few years and will expand further. Thus, this review will provide the status quo and will lay the foundation for new and exciting avenues in liver membrane transporter research.
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Affiliation(s)
- Tim Kroll
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Martin Prescher
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Sander H J Smits
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.,Center for Structural Studies, Heinrich Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
| | - Lutz Schmitt
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany
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Thulasingam M, Haeggström JZ. Integral Membrane Enzymes in Eicosanoid Metabolism: Structures, Mechanisms and Inhibitor Design. J Mol Biol 2020; 432:4999-5022. [PMID: 32745470 DOI: 10.1016/j.jmb.2020.07.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 12/14/2022]
Abstract
Eicosanoids are potent lipid mediators involved in central physiological processes such as hemostasis, renal function and parturition. When formed in excess, eicosanoids become critical players in a range of pathological conditions, in particular pain, fever, arthritis, asthma, cardiovascular disease and cancer. Eicosanoids are generated via oxidative metabolism of arachidonic acid along the cyclooxygenase (COX) and lipoxygenase (LOX) pathways. Specific lipid species are formed downstream of COX and LOX by specialized synthases, some of which reside on the nuclear and endoplasmic reticulum, including mPGES-1, FLAP, LTC4 synthase, and MGST2. These integral membrane proteins are members of the family "membrane-associated proteins in eicosanoid and glutathione metabolism" (MAPEG). Here we focus on this enzyme family, which encompasses six human members typically catalyzing glutathione dependent transformations of lipophilic substrates. Enzymes of this family have evolved to combat the topographical challenge and unfavorable energetics of bringing together two chemically different substrates, from cytosol and lipid bilayer, for catalysis within a membrane environment. Thus, structural understanding of these enzymes are of utmost importance to unravel their molecular mechanisms, mode of substrate entry and product release, in order to facilitate novel drug design against severe human diseases.
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Affiliation(s)
- Madhuranayaki Thulasingam
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
| | - Jesper Z Haeggström
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
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6
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Abstract
The mercapturic acid pathway is a major route for the biotransformation of xenobiotic and endobiotic electrophilic compounds and their metabolites. Mercapturic acids (N-acetyl-l-cysteine S-conjugates) are formed by the sequential action of the glutathione transferases, γ-glutamyltransferases, dipeptidases, and cysteine S-conjugate N-acetyltransferase to yield glutathione S-conjugates, l-cysteinylglycine S-conjugates, l-cysteine S-conjugates, and mercapturic acids; these metabolites constitute a "mercapturomic" profile. Aminoacylases catalyze the hydrolysis of mercapturic acids to form cysteine S-conjugates. Several renal transport systems facilitate the urinary elimination of mercapturic acids; urinary mercapturic acids may serve as biomarkers for exposure to chemicals. Although mercapturic acid formation and elimination is a detoxication reaction, l-cysteine S-conjugates may undergo bioactivation by cysteine S-conjugate β-lyase. Moreover, some l-cysteine S-conjugates, particularly l-cysteinyl-leukotrienes, exert significant pathophysiological effects. Finally, some enzymes of the mercapturic acid pathway are described as the so-called "moonlighting proteins," catalytic proteins that exert multiple biochemical or biophysical functions apart from catalysis.
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Affiliation(s)
- Patrick E Hanna
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN, USA
| | - M W Anders
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, USA
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Raabe J, Arend C, Steinmeier J, Dringen R. Dicoumarol Inhibits Multidrug Resistance Protein 1-Mediated Export Processes in Cultured Primary Rat Astrocytes. Neurochem Res 2018; 44:333-346. [PMID: 30443714 DOI: 10.1007/s11064-018-2680-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/05/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022]
Abstract
Dicoumarol is frequently used as inhibitor of the detoxifying enzyme NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1). In order to test whether dicoumarol may also affect the cellular glutathione (GSH) metabolism, we have exposed cultured primary astrocytes to dicoumarol and investigated potential effects of this compound on the cell viability as well as on the cellular and extracellular contents of GSH and its metabolites. Incubation of astrocytes with dicoumarol in concentrations of up to 100 µM did not acutely compromise cell viability nor was any GSH consumption or GSH oxidation to glutathione disulfide (GSSG) observed. However, unexpectedly dicoumarol inhibited the cellular multidrug resistance protein (Mrp) 1-dependent export of GSH in a time- and concentration-dependent manner with half-maximal effects observed at low micromolar concentrations of dicoumarol. Inhibition of GSH export by dicoumarol was not additive to that observed for the known Mrp1 inhibitor MK571. In addition, dicoumarol inhibited also the Mrp1-mediated export of GSSG during menadione-induced oxidative stress and the export of the GSH-bimane-conjugate (GS-B) that had been generated in the cells after exposure to monochlorobimane. Half-maximal inhibition of the export of Mrp1 substrates was observed at dicoumarol concentrations of around 4 µM (GSH and GSSG) and 30 µM (GS-B). These data demonstrate that dicoumarol strongly affects the GSH metabolism of viable cultured astrocytes by inhibiting Mrp1-mediated export processes and identifies for the first time Mrp1 as additional cellular target of dicoumarol.
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Affiliation(s)
- Janice Raabe
- Centre for Biomolecular Interactions Bremen, Faculty 2 (Biology/Chemistry), University of Bremen, P.O. Box 330440, 28334, Bremen, Germany
| | - Christian Arend
- Centre for Biomolecular Interactions Bremen, Faculty 2 (Biology/Chemistry), University of Bremen, P.O. Box 330440, 28334, Bremen, Germany.,Centre for Environmental Research and Sustainable Technology, University of Bremen, Bremen, Germany
| | - Johann Steinmeier
- Centre for Biomolecular Interactions Bremen, Faculty 2 (Biology/Chemistry), University of Bremen, P.O. Box 330440, 28334, Bremen, Germany.,Centre for Environmental Research and Sustainable Technology, University of Bremen, Bremen, Germany
| | - Ralf Dringen
- Centre for Biomolecular Interactions Bremen, Faculty 2 (Biology/Chemistry), University of Bremen, P.O. Box 330440, 28334, Bremen, Germany. .,Centre for Environmental Research and Sustainable Technology, University of Bremen, Bremen, Germany.
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8
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Adaptor protein-3: A key player in RBL-2H3 mast cell mediator release. PLoS One 2017; 12:e0173462. [PMID: 28273137 PMCID: PMC5342237 DOI: 10.1371/journal.pone.0173462] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 02/22/2017] [Indexed: 11/30/2022] Open
Abstract
Mast cell (MC) secretory granules are Lysosome-Related Organelles (LROs) whose biogenesis is associated with the post-Golgi secretory and endocytic pathways in which the sorting of proteins destined for a specific organelle relies on the recognition of sorting signals by adaptor proteins that direct their incorporation into transport vesicles. The adaptor protein 3 (AP-3) complex mediates protein trafficking between the trans-Golgi network (TGN) and late endosomes, lysosomes, and LROs. AP-3 has a recognized role in LROs biogenesis and regulated secretion in several cell types, including many immune cells such as neutrophils, natural killer cells, and cytotoxic T lymphocytes. However, the relevance of AP-3 for these processes in MCs has not been previously investigated. AP-3 was found to be expressed and distributed in a punctate fashion in rat peritoneal mast cells ex vivo. The rat MC line RBL-2H3 was used as a model system to investigate the role of AP-3 in mast cell secretory granule biogenesis and mediator release. By immunofluorescence and immunoelectron microscopy, AP-3 was localized both to the TGN and early endosomes indicating that AP-3 dependent sorting of proteins to MC secretory granules originates in these organelles. ShRNA mediated depletion of the AP-3 δ subunit was shown to destabilize the AP-3 complex in RBL-2H3 MCs. AP-3 knockdown significantly affected MC regulated secretion of β-hexosaminidase without affecting total cellular enzyme levels. Morphometric evaluation of MC secretory granules by electron microscopy revealed that the area of MC secretory granules in AP-3 knockdown MCs was significantly increased, indicating that AP-3 is involved in MC secretory granule biogenesis. Furthermore, AP-3 knockdown had a selective impact on the secretion of newly formed and newly synthesized mediators. These results show for the first time that AP-3 plays a critical role in secretory granule biogenesis and mediator release in MCs.
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9
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Andersen V, Svenningsen K, Knudsen LA, Hansen AK, Holmskov U, Stensballe A, Vogel U. Novel understanding of ABC transporters ABCB1/MDR/P-glycoprotein, ABCC2/MRP2, and ABCG2/BCRP in colorectal pathophysiology. World J Gastroenterol 2015; 21:11862-11876. [PMID: 26557010 PMCID: PMC4631984 DOI: 10.3748/wjg.v21.i41.11862] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 08/07/2015] [Accepted: 09/30/2015] [Indexed: 02/06/2023] Open
Abstract
AIM: To evaluate ATP-binding cassette (ABC) transporters in colonic pathophysiology as they had recently been related to colorectal cancer (CRC) development.
METHODS: Literature search was conducted on PubMed using combinations of the following terms: ABC transporters, ATP binding cassette transporter proteins, inflammatory bowel disease, ulcerative, colitis, Crohns disease, colorectal cancer, colitis, intestinal inflammation, intestinal carcinogenesis, ABCB1/P-glycoprotein (P-gp/CD243/MDR1), ABCC2/multidrug resistance protein 2 (MRP2) and ABCG2/breast cancer resistance protein (BCRP), Abcb1/Mdr1a, abcc2/Mrp2, abcg2/Bcrp, knock-out mice, tight junction, membrane lipid function.
RESULTS: Recently, human studies reported that changes in the levels of ABC transporters were early events in the adenoma-carcinoma sequence leading to CRC. A link between ABCB1, high fat diet and gut microbes in relation to colitis was suggested by the animal studies. The finding that colitis was preceded by altered gut bacterial composition suggests that deletion of Abcb1 leads to fundamental changes of host-microbiota interaction. Also, high fat diet increases the frequency and severity of colitis in specific pathogen-free Abcb1 KO mice. The Abcb1 KO mice might thus serve as a model in which diet/environmental factors and microbes may be controlled and investigated in relation to intestinal inflammation. Potential molecular mechanisms include defective transport of inflammatory mediators and/or phospholipid translocation from one side to the other of the cell membrane lipid bilayer by ABC transporters affecting inflammatory response and/or function of tight junctions, phagocytosis and vesicle trafficking. Also, diet and microbes give rise to molecules which are potential substrates for the ABC transporters and which may additionally affect ABC transporter function through nuclear receptors and transcriptional regulation. Another critical role of ABCB1 was suggested by the finding that ABCB1 expression identifies a subpopulation of pro-inflammatory Th17 cells which were resistant to treatment with glucocorticoids. The evidence for the involvement of ABCC2 and ABCG2 in colonic pathophysiology was weak.
CONCLUSION: ABCB1, diet, and gut microbes mutually interact in colonic inflammation, a well-known risk factor for CRC. Further insight may be translated into preventive and treatment strategies.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B/genetics
- ATP Binding Cassette Transporter, Subfamily B/metabolism
- ATP Binding Cassette Transporter, Subfamily G, Member 2
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/metabolism
- Animals
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Colorectal Neoplasms/genetics
- Colorectal Neoplasms/metabolism
- Colorectal Neoplasms/pathology
- Colorectal Neoplasms/physiopathology
- Disease Models, Animal
- Genetic Predisposition to Disease
- Humans
- Inflammatory Bowel Diseases/genetics
- Inflammatory Bowel Diseases/metabolism
- Inflammatory Bowel Diseases/pathology
- Inflammatory Bowel Diseases/physiopathology
- Mice, Transgenic
- Multidrug Resistance-Associated Protein 2
- Multidrug Resistance-Associated Proteins/genetics
- Multidrug Resistance-Associated Proteins/metabolism
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Phenotype
- Polymorphism, Genetic
- Tumor Microenvironment
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Andersen V, Vogel U. Interactions between meat intake and genetic variation in relation to colorectal cancer. GENES AND NUTRITION 2014; 10:448. [PMID: 25491747 PMCID: PMC4261072 DOI: 10.1007/s12263-014-0448-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 11/28/2014] [Indexed: 01/03/2023]
Abstract
Meat intake is associated with the risk of colorectal cancer. The objective of this systematic review was to evaluate interactions between meat intake and genetic variation in order to identify biological pathways involved in meat carcinogenesis. We performed a literature search of PubMed and Embase using “interaction”, “meat”, “polymorphisms”, and “colorectal cancer”, and data on meat–gene interactions were extracted. The studies were divided according to whether information on meat intake was collected prospectively or retrospectively. In prospective studies, interactions between meat intake and polymorphisms in PTGS2 (encoding COX-2), ABCB1, IL10, NFKB1, MSH3, XPC (Pint = 0.006, 0.01, 0.04, 0.03, 0.002, 0.01, respectively), but not IL1B, HMOX1, ABCC2, ABCG2, NR1I2 (encoding PXR), NR1H2 (encoding LXR), NAT1, NAT2, MSH6, or MLH1 in relation to CRC were found. Interaction between a polymorphism in XPC and meat was found in one prospective and one case–control study; however, the directions of the risk estimates were opposite. Thus, none of the findings were replicated. The results from this systematic review suggest that genetic variation in the inflammatory response and DNA repair pathway is involved in meat-related colorectal carcinogenesis, whereas no support for the involvement of heme and iron from meat or cooking mutagens was found. Further studies assessing interactions between meat intake and genetic variation in relation to CRC in large well-characterised prospective cohorts with relevant meat exposure are warranted.
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Affiliation(s)
- Vibeke Andersen
- Organ Center, Hospital of Southern Jutland, Aabenraa, Denmark,
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11
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Moon TC, Befus AD, Kulka M. Mast cell mediators: their differential release and the secretory pathways involved. Front Immunol 2014; 5:569. [PMID: 25452755 PMCID: PMC4231949 DOI: 10.3389/fimmu.2014.00569] [Citation(s) in RCA: 273] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Accepted: 10/23/2014] [Indexed: 12/14/2022] Open
Abstract
Mast cells (MC) are widely distributed throughout the body and are common at mucosal surfaces, a major host-environment interface. MC are functionally and phenotypically heterogeneous depending on the microenvironment in which they mature. Although MC have been classically viewed as effector cells of IgE-mediated allergic diseases, they are also recognized as important in host defense, innate and acquired immunity, homeostatic responses, and immunoregulation. MC activation can induce release of pre-formed mediators such as histamine from their granules, as well as release of de novo synthesized lipid mediators, cytokines, and chemokines that play diverse roles, not only in allergic reactions but also in numerous physiological and pathophysiological responses. Indeed, MC release their mediators in a discriminating and chronological manner, depending upon the stimuli involved and their signaling cascades (e.g., IgE-mediated or Toll-like receptor-mediated). However, the precise mechanisms underlying differential mediator release in response to these stimuli are poorly known. This review summarizes our knowledge of MC mediators and will focus on what is known about the discriminatory release of these mediators dependent upon diverse stimuli, MC phenotypes, and species of origin, as well as on the intracellular synthesis, storage, and secretory processes involved.
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Affiliation(s)
- Tae Chul Moon
- Pulmonary Research Group, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - A. Dean Befus
- Pulmonary Research Group, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Marianna Kulka
- National Institute for Nanotechnology, National Research Council, Edmonton, AB, Canada
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12
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Abstract
In the mammalian kidney, prostaglandins (PGs) are important mediators of physiologic processes, including modulation of vascular tone and salt and water. PGs arise from enzymatic metabolism of free arachidonic acid (AA), which is cleaved from membrane phospholipids by phospholipase A2 activity. The cyclooxygenase (COX) enzyme system is a major pathway for metabolism of AA in the kidney. COX are the enzymes responsible for the initial conversion of AA to PGG2 and subsequently to PGH2, which serves as the precursor for subsequent metabolism by PG and thromboxane synthases. In addition to high levels of expression of the "constitutive" rate-limiting enzyme responsible for prostanoid production, COX-1, the "inducible" isoform of cyclooxygenase, COX-2, is also constitutively expressed in the kidney and is highly regulated in response to alterations in intravascular volume. PGs and thromboxane A2 exert their biological functions predominantly through activation of specific 7-transmembrane G-protein-coupled receptors. COX metabolites have been shown to exert important physiologic functions in maintenance of renal blood flow, mediation of renin release and regulation of sodium excretion. In addition to physiologic regulation of prostanoid production in the kidney, increases in prostanoid production are also seen in a variety of inflammatory renal injuries, and COX metabolites may serve as mediators of inflammatory injury in renal disease.
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Affiliation(s)
- Raymond C Harris
- George M. O'Brien Kidney and Urologic Diseases Center and Division of Nephrology, Vanderbilt University School of Medicine and Nashville Veterans Affairs Hospital, Nashville, Tennessee, USA.
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13
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Folseraas T, Melum E, Rausch P, Juran BD, Ellinghaus E, Shiryaev A, Laerdahl JK, Ellinghaus D, Schramm C, Weismüller TJ, Gotthardt DN, Hov JR, Clausen OP, Weersma RK, Janse M, Boberg KM, Björnsson E, Marschall HU, Cleynen I, Rosenstiel P, Holm K, Teufel A, Rust C, Gieger C, Wichmann HE, Bergquist A, Ryu E, Ponsioen CY, Runz H, Sterneck M, Vermeire S, Beuers U, Wijmenga C, Schrumpf E, Manns MP, Lazaridis KN, Schreiber S, Baines JF, Franke A, Karlsen TH. Extended analysis of a genome-wide association study in primary sclerosing cholangitis detects multiple novel risk loci. J Hepatol 2012; 57:366-75. [PMID: 22521342 PMCID: PMC3399030 DOI: 10.1016/j.jhep.2012.03.031] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 03/07/2012] [Accepted: 03/26/2012] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS A limited number of genetic risk factors have been reported in primary sclerosing cholangitis (PSC). To discover further genetic susceptibility factors for PSC, we followed up on a second tier of single nucleotide polymorphisms (SNPs) from a genome-wide association study (GWAS). METHODS We analyzed 45 SNPs in 1221 PSC cases and 3508 controls. The association results from the replication analysis and the original GWAS (715 PSC cases and 2962 controls) were combined in a meta-analysis comprising 1936 PSC cases and 6470 controls. We performed an analysis of bile microbial community composition in 39 PSC patients by 16S rRNA sequencing. RESULTS Seventeen SNPs representing 12 distinct genetic loci achieved nominal significance (p(replication) <0.05) in the replication. The most robust novel association was detected at chromosome 1p36 (rs3748816; p(combined)=2.1 × 10(-8)) where the MMEL1 and TNFRSF14 genes represent potential disease genes. Eight additional novel loci showed suggestive evidence of association (p(repl) <0.05). FUT2 at chromosome 19q13 (rs602662; p(comb)=1.9 × 10(-6), rs281377; p(comb)=2.1 × 10(-6) and rs601338; p(comb)=2.7 × 10(-6)) is notable due to its implication in altered susceptibility to infectious agents. We found that FUT2 secretor status and genotype defined by rs601338 significantly influence biliary microbial community composition in PSC patients. CONCLUSIONS We identify multiple new PSC risk loci by extended analysis of a PSC GWAS. FUT2 genotype needs to be taken into account when assessing the influence of microbiota on biliary pathology in PSC.
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Affiliation(s)
- Trine Folseraas
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Research institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Espen Melum
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Research institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Philipp Rausch
- Institute for Experimental Medicine, Christian-Albrechts-University of Kiel, Kiel, Germany
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Brian D. Juran
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology and Hepatology, Mayo Clinic, College of Medicine, Rochester, Minnesota, United States of America
| | - Eva Ellinghaus
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Alexey Shiryaev
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Research institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Jon K. Laerdahl
- Centre for Molecular Biology and Neuroscience (CMBN) and Department of Microbiology, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Bioinformatics Core Facility, Department of Informatics, University of Oslo, Oslo, Norway
| | - David Ellinghaus
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Christoph Schramm
- 1 Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tobias J. Weismüller
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
- Integrated Research and Treatment Center-Transplantation (IFB-tx), Hannover Medical School, Hannover, Germany
| | | | - Johannes Roksund Hov
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Research institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Ole Petter Clausen
- Faculty of Medicine, University of Oslo, Oslo, Norway
- Division of Pathology, Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - Rinse K. Weersma
- Department of Gastroenterology and Hepatology, University Medical Center Groningen and University of Groningen, The Netherlands
| | - Marcel Janse
- Department of Gastroenterology and Hepatology, University Medical Center Groningen and University of Groningen, The Netherlands
| | - Kirsten Muri Boberg
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Einar Björnsson
- Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy and University Hospital, Gothenburg, Sweden
| | - Hanns-Ulrich Marschall
- Department of Internal Medicine, Institute of Medicine, Sahlgrenska Academy and University Hospital, Gothenburg, Sweden
| | - Isabelle Cleynen
- Department of Gastroenterology, University Hospital Gasthuisberg, Leuven, Belgium
| | - Philip Rosenstiel
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Kristian Holm
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Andreas Teufel
- 1 Department of Medicine, University of Mainz, Mainz, Germany
| | - Christian Rust
- Department of Medicine 2, Grosshadern, University of Munich, Munich, Germany
| | - Christian Gieger
- Institute of Genetic Epidemiology, Helmholtz Center Munich, German Research, Center for Environmental Health, Neuherberg, Germany
| | - H-Erich Wichmann
- Institute of Epidemiology I, Helmholtz Center Munich, German Research Center for Environmental Health, Neuherberg, Germany
- Institute of Medical Informatics, Biometry and Epidemiology, Ludwig-Maximilians-Universität, Munich, Germany
- Klinikum Grosshadern, Munich, Germany
| | - Annika Bergquist
- Department of Gastroenterology and Hepatology, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Euijung Ryu
- Division of Biomedical Statistics and Informatics, Mayo Clinic College of Medicine, Rochester, Minnesota, Unites States of America
| | - Cyriel Y. Ponsioen
- Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Heiko Runz
- Department of Human Genetics, University Hospital of Heidelberg, Heidelberg, Germany
| | - Martina Sterneck
- Department of Hepatobiliary Surgery and Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Severine Vermeire
- Department of Gastroenterology, University Hospital Gasthuisberg, Leuven, Belgium
| | - Ulrich Beuers
- Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Cisca Wijmenga
- Department of Genetics, University Medical Center Groningen and University of Groningen, Groningen, the Netherlands
| | - Erik Schrumpf
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Michael P. Manns
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany
- Integrated Research and Treatment Center-Transplantation (IFB-tx), Hannover Medical School, Hannover, Germany
| | - Konstantinos N. Lazaridis
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology and Hepatology, Mayo Clinic, College of Medicine, Rochester, Minnesota, United States of America
| | - Stefan Schreiber
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
- Department for General Internal Medicine, Christian-Albrechts-University, Kiel, Germany
| | - John F. Baines
- Institute for Experimental Medicine, Christian-Albrechts-University of Kiel, Kiel, Germany
- Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Andre Franke
- Institute of Clinical Molecular Biology, Christian-Albrechts-University, Kiel, Germany
| | - Tom H. Karlsen
- Norwegian PSC research center, Department of transplantation medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Research institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, Oslo, Norway
- Division of Gastroenterology, Institute of Medicine, University of Bergen, Bergen, Norway
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14
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Abstract
ABC (ATP-binding cassette) proteins actively transport a wide variety of substrates, including peptides, amino acids, sugars, metals, drugs, vitamins and lipids, across extracellular and intracellular membranes. Of the 49 hum an ABC proteins, a significant number are known to mediate the extrusion of lipids from membranes or the flipping of membrane lipids across the bilayer to generate and maintain membrane lipid asymmetry. Typical lipid substrates include phospholipids, sterols, sphingolipids, bile acids and related lipid conjugates. Members of the ABCA subfamily of ABC transporters and other ABC proteins such as ABCB4, ABCG1 and ABCG5/8 implicated in lipid transport play important roles in diverse biological processes such as cell signalling, membrane lipid asymmetry, removal of potentially toxic compounds and metabolites, and apoptosis. The importance of these ABC lipid transporters in cell physiology is evident from the finding that mutations in the genes encoding many of these proteins are responsible for severe inherited diseases. For example, mutations in ABCA1 cause Tangier disease associated with defective efflux of cholesterol and phosphatidylcholine from the plasma membrane to the lipid acceptor protein apoA1 (apolipoprotein AI), mutations in ABCA3 cause neonatal surfactant deficiency associated with a loss in secretion of the lipid pulmonary surfactants from lungs of newborns, mutations in ABCA4 cause Stargardt macular degeneration, a retinal degenerative disease linked to the reduced clearance of retinoid compounds from photoreceptor cells, mutations in ABCA12 cause harlequin and lamellar ichthyosis, skin diseases associated with defective lipid trafficking in keratinocytes, and mutations in ABCB4 and ABCG5/ABCG8 are responsible for progressive intrafamilial hepatic disease and sitosterolaemia associated with defective phospholipid and sterol transport respectively. This chapter highlights the involvement of various mammalian ABC transporters in lipid transport in the context of their role in cell signalling, cellular homoeostasis, apoptosis and inherited disorders.
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15
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Bozza PT, Bakker-Abreu I, Navarro-Xavier RA, Bandeira-Melo C. Lipid body function in eicosanoid synthesis: an update. Prostaglandins Leukot Essent Fatty Acids 2011; 85:205-13. [PMID: 21565480 DOI: 10.1016/j.plefa.2011.04.020] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Eicosanoids (prostaglandins, leukotrienes and lipoxins) are signaling lipids derived from arachidonic acid metabolism that have important roles in physiological and pathological processes. Lately, intracellular compartmentalization of eicosanoid-synthetic machinery has emerged as a key component in the regulation of eicosanoid synthesis and functions. Over the past years substantial progresses have been made demonstrating that precursors and enzymes involved in eicosanoid synthesis localize at lipid bodies (also known as lipid droplets) and lipid bodies are distinct sites for eicosanoid generation. Here we will review the current knowledge on the functions of lipid bodies as specialized intracellular sites of compartmentalization of signaling with major roles in eicosanoid formation within cells engaged in inflammatory, infectious and neoplastic process.
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Affiliation(s)
- Patricia T Bozza
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, FIOCRUZ, Brazil.
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16
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Jemnitz K, Heredi-Szabo K, Janossy J, Ioja E, Vereczkey L, Krajcsi P. ABCC2/Abcc2: a multispecific transporter with dominant excretory functions. Drug Metab Rev 2010; 42:402-36. [PMID: 20082599 DOI: 10.3109/03602530903491741] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
ABCC2/Abcc2 (MRP2/Mrp2) is expressed at major physiological barriers, such as the canalicular membrane of liver cells, kidney proximal tubule epithelial cells, enterocytes of the small and large intestine, and syncytiotrophoblast of the placenta. ABCC2/Abcc2 always localizes in the apical membranes. Although ABCC2/Abcc2 transports a variety of amphiphilic anions that belong to different classes of molecules, such as endogenous compounds (e.g., bilirubin-glucuronides), drugs, toxic chemicals, nutraceuticals, and their conjugates, it displays a preference for phase II conjugates. Phenotypically, the most obvious consequence of mutations in ABCC2 that lead to Dubin-Johnson syndrome is conjugate hyperbilirubinemia. ABCC2/Abcc2 harbors multiple binding sites and displays complex transport kinetics.
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Affiliation(s)
- Katalin Jemnitz
- Chemical Research Center, Institute of Biomolecular Chemistry, HAS, Budapest, Hungary
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17
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Kuppens IELM, Breedveld P, Beijnen JH, Schellens JHM. Modulation of Oral Drug Bioavailability: From Preclinical Mechanism to Therapeutic Application. Cancer Invest 2009; 23:443-64. [PMID: 16193644 DOI: 10.1081/cnv-58823] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Currently, more than one fourth of all anticancer drugs are developed as oral formulations, and it is expected that this number will increase substantially in the near future. To enable oral drug therapy, adequate oral bioavailability must be achieved. Factors that have proved to be important in limiting the oral bioavailability are the presence of ATP-binding cassette drug transporters (ABC transporters) and the cytochrome P450 enzymes. We discuss the tissues distribution and physiological function of the ABC transporters in the human body, their expression in tumors, currently known polymorphisms and drugs that are able to inhibit their function as transporter. Furthermore, the role of the ABC transporters and drug-metabolizing enzymes as mechanisms to modulate the pharmacokinetics of anticancer agents, will be reviewed. Finally, some clinical examples of oral drug modulation are discussed. Among these examples are the coadministration of paclitaxel with CsA, a CYP3A4 substrate with P-glycoprotein (P-gp) modulating activity, and topotecan combined with the BCRP/P-gp transport inhibitor elacridar. Both are good examples of improvement of oral drug bioavailability by temporary inhibition of drug transporters in the gut epithelium.
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Affiliation(s)
- Isa E L M Kuppens
- Department of Medical Oncology, Antoni van Leeuwenhoek Hospital/The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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18
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Transport of lipids by ABC proteins: interactions and implications for cellular toxicity, viability and function. Chem Biol Interact 2009; 180:327-39. [PMID: 19426719 DOI: 10.1016/j.cbi.2009.04.012] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Revised: 04/15/2009] [Accepted: 04/24/2009] [Indexed: 12/16/2022]
Abstract
Members of the ATP-binding cassette (ABC) family of membrane-bound transporters are involved in multiple aspects of transport and redistribution of various lipids and their conjugates. Most ABC transporters localize to the plasma membrane; some are associated with liquid-ordered cholesterol-/sphingolipid-rich microdomains, and to a lesser extent the membranes of the Golgi and endoplasmic reticulum. Hence, ABC transporters are well placed to regulate plasma membrane lipid composition and the efflux and redistribution of structural phospholipids and sphingolipids during periods of cellular stress and recovery. ABC transporters can also modulate cellular sensitivity to extrinsic pro-apoptotic signals through regulation of sphingomyelin-ceramide biosynthesis and metabolism. The functionality of ABC transporters is, in turn, modulated by the lipid content of the microdomains in which they reside. Cholesterol, a major membrane microdomain component, is not only a substrate of several ABC transporters, but also regulates ABC activity through its effects on microdomain structure. Several important bioactive lipid mediators and toxic lipid metabolites are also effluxed by ABC transporters. In this review, the complex interactions between ABC transporters and their lipid/sterol substrates will be discussed and analyzed in the context of their relevance to cellular function, toxicity and apoptosis.
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19
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González-Pons M, Szeto AC, González-Méndez R, Serrano AE. Identification and bioinformatic characterization of a multidrug resistance associated protein (ABCC) gene in Plasmodium berghei. Malar J 2009; 8:1. [PMID: 19118502 PMCID: PMC2630995 DOI: 10.1186/1475-2875-8-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Accepted: 01/02/2009] [Indexed: 11/25/2022] Open
Abstract
Background The ATP-binding cassette (ABC) superfamily is one of the largest evolutionarily conserved families of proteins. ABC proteins play key roles in cellular detoxification of endobiotics and xenobiotics. Overexpression of certain ABC proteins, among them the multidrug resistance associated protein (MRP), contributes to drug resistance in organisms ranging from human neoplastic cells to parasitic protozoa. In the present study, the Plasmodium berghei mrp gene (pbmrp) was partially characterized and the predicted protein was classified using bioinformatics in order to explore its putative involvement in drug resistance. Methods The pbmrp gene from the P. berghei drug sensitive, N clone, was sequenced using a PCR strategy. Classification and domain organization of pbMRP were determined with bioinformatics. The Plasmodium spp. MRPs were aligned and analysed to study their conserved motifs and organization. Gene copy number and organization were determined via Southern blot analysis in both N clone and the chloroquine selected line, RC. Chromosomal Southern blots and RNase protection assays were employed to determine the chromosomal location and expression levels of pbmrp in blood stages. Results The pbmrp gene is a single copy, intronless gene with a predicted open reading frame spanning 5820 nucleotides. Bioinformatic analyses show that this protein has distinctive features characteristic of the ABCC sub-family. Multiple sequence alignments reveal a high degree of conservation in the nucleotide binding and transmembrane domains within the MRPs from the Plasmodium spp. analysed. Expression of pbmrp was detected in asexual blood stages. Gene organization, copy number and mRNA expression was similar in both lines studied. A chromosomal translocation was observed in the chloroquine selected RC line, from chromosome 13/14 to chromosome 8, when compared to the drug sensitive N clone. Conclusion In this study, the pbmrp gene was sequenced and classified as a member of the ABCC sub-family. Multiple sequence alignments reveal that this gene is homologous to the Plasmodium y. yoelii and Plasmodium knowlesi mrp, and the Plasmodium vivax and Plasmodium falciparum mrp2 genes. There were no differences in gene organization, copy number, or mRNA expression between N clone and the RC line, but a chromosomal translocation of pbmrp from chromosome 13/14 to chromosome 8 was detected in RC.
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Affiliation(s)
- María González-Pons
- Department of Microbiology, University of Puerto Rico School of Medicine, PO Box 365067, San Juan, PR 00936-5067, USA.
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20
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Skazik C, Heise R, Bostanci O, Paul N, Denecke B, Joussen S, Kiehl K, Merk HF, Zwadlo-Klarwasser G, Baron JM. Differential expression of influx and efflux transport proteins in human antigen presenting cells. Exp Dermatol 2008; 17:739-47. [PMID: 18557925 DOI: 10.1111/j.1600-0625.2008.00745.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Human macrophages (M Phi) express cytochrome P450 enzymes verifying their capacity to metabolize a variety of endogenous and exogenous substances. Here we analysed the mRNA and protein expression of transport proteins involved in the uptake or export of drugs, hormones and arachidonic acid metabolites in dendritic cells (DC) and M Phi compared to their precursors - blood monocytes - using cDNA microarray, RT-PCR, Western-blot and immunostaining techniques. The transport proteins studied included members of the solute carrier organic anion transporter family (SLCO) and the multidrug resistance associated proteins (MRP) 1-6 belonging to the ATP-binding cassette subfamily C (ABCC). We found that only mRNA for SLCO-2B1, -3A1, and -4A1 were present in monocytes, M Phi and DC. Most interestingly the expression of SLCO-2B1 was markedly enhanced in M Phi as compared to monocytes and DC. The presence of mRNA for ABCC1, 3, 4, 5 and 6 in all three cell types was demonstrated. On protein level ABCC1/MRP1 which has been identified as leukotriene C(4) transporter was found to be the most abundant transporter in M Phi and DC. Blocking the ABCC1/MRP1 activity with the specific inhibitor MK571 resulted in a phenotypic change in DC but not in M Phi. Our data show that human blood monocytes and monocyte derived M Phi as well as DC express a specific profile of transporters involved in uptake and export of exogenous molecules like allergens or drugs, but also of endogenous substances in particular of inflammatory lipid mediators like leukotrienes and prostaglandins.
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Affiliation(s)
- Claudia Skazik
- Department of Dermatology, University Hospital RWTH Aachen, Aachen, Germany
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21
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Pedersen JM, Matsson P, Bergström CAS, Norinder U, Hoogstraate J, Artursson P. Prediction and identification of drug interactions with the human ATP-binding cassette transporter multidrug-resistance associated protein 2 (MRP2; ABCC2). J Med Chem 2008; 51:3275-87. [PMID: 18457386 DOI: 10.1021/jm7015683] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The chemical space of registered oral drugs was explored for inhibitors of the human multidrug-resistance associated protein 2 (MRP2; ABCC2), using a data set of 191 structurally diverse drugs and drug-like compounds. The data set included a new reference set of 75 compounds, for studies of hepatic drug interactions with transport proteins, CYP enzymes, and compounds associated with liver toxicity. The inhibition of MRP2-mediated transport of estradiol-17beta-D-glucuronide was studied in inverted membrane vesicles from Sf9 cells overexpressing human MRP2. A total of 27 previously unknown MRP2 inhibitors were identified, and the results indicate an overlapping but narrower inhibitor space for MRP2 compared with the two other major ABC efflux transporters P-gp (ABCB1) and BCRP (ABCG2). In addition, 13 compounds were shown to stimulate the transport of estradiol-17beta-D-glucuronide. The experimental results were used to develop a computational model able to discriminate inhibitors from noninhibitors according to their molecular structure, resulting in a predictive power of 86% for the training set and 72% for the test set. The inhibitors were in general larger and more lipophilic and presented a higher aromaticity than the noninhibitors. The developed computational model is applicable in an early stage of the drug discovery process and is proposed as a tool for prediction of MRP2-mediated hepatic drug interactions and toxicity.
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Affiliation(s)
- Jenny M Pedersen
- Pharmaceutical Screening and Informatics, Department of Pharmacy, Uppsala University, Biomedical Center, Uppsala, Sweden
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22
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Reichel V, Masereeuw R, van den Heuvel JJMW, Miller DS, Fricker G. Transport of a fluorescent cAMP analog in teleost proximal tubules. Am J Physiol Regul Integr Comp Physiol 2007; 293:R2382-9. [PMID: 17855498 DOI: 10.1152/ajpregu.00029.2007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have shown that killifish (Fundulus heteroclitus) renal proximal tubules express a luminal membrane transporter that is functionally and immunologically analogous to the mammalian multidrug resistance-associated protein isoform 2 (Mrp2, ABCC2). Here we used confocal microscopy to investigate in killifish tubules the transport of a fluorescent cAMP analog (fluo-cAMP), a putative substrate for Mrp2 and Mrp4 (ABCC4). Steady-state luminal accumulation of fluo-cAMP was concentrative, specific, and metabolism-dependent, but not reduced by high K+ medium or ouabain. Transport was not affected by p-aminohippurate (organic anion transporter inhibitor) or p-glycoprotein inhibitor (PSC833), but cell-to-lumen transport was reduced in a concentration-dependent manner by Mrp inhibitor MK571, leukotriene C4 (LTC4), azidothymidine (AZT), cAMP, and adefovir; the latter two compounds are Mrp4 substrates. Although MK571 and LTC4 reduced transport of the Mrp2 substrate fluorescein-methotrexate (FL-MTX), neither cAMP, adefovir, nor AZT affected FL-MTX transport. Fluo-cAMP transport was not reduced when tubules were exposed to endothelin-1, Na nitroprusside (an nitric oxide generator) or phorbol ester (PKC activator), all of which signal substantial reductions in cell-to-lumen FL-MTX transport. Fluo-cAMP transport was reduced by forskolin, and this reduction was blocked by the PKA inhibitor H-89. Finally, in membrane vesicles from Spodoptera frugiperda (Sf9) cells containing human MRP4, ATP-dependent and specific uptake of fluo-cAMP could be demonstrated. Thus, based on inhibitor specificity and regulatory signaling, cell-to-lumen transport of fluo-cAMP in killifish renal tubules is mediated by a transporter distinct from Mrp2, presumably a teleost form of Mrp4.
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Affiliation(s)
- Valeska Reichel
- Institute of Pharmacy and Molecular Biotechnology, INF 366, 69120 Heidelberg, Germany
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23
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Fujiyama N, Shitara Y, Ito K, Masubuchi Y, Horie T. Down-Regulation of Hepatic Transporters for BSP in Rats with Indomethacin-Induced Intestinal Injury. Biol Pharm Bull 2007; 30:556-61. [PMID: 17329856 DOI: 10.1248/bpb.30.556] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous reports have demonstrated that an intestinal injury causes hypofunctions of the liver associated with down-regulations of cytochrome P450, but an influence on hepatic transporters remains unclear. Here, we tested hepatic transporter functions in a rat model of bowel injury using indomethacin (IDM). After administration of IDM (8.5 mg/kg, i.p., 3 d), the rats suffered the intestinal impairment indicated by a reduction of alkaline phosphatase activity in mucosa. In vivo pharmacokinetic experiments of bromosulfophthalein (BSP) showed that there was a reduction in its plasma elimination rate and cumulative biliary excretion in IDM-treated rats and systemic and biliary clearances reduced to nearly 50% of the control group. Protein expressions in plasma membrane and mRNA levels of organic anion transporting polypeptide 1b2 (Oatp1b2) and multidrug resistance-associated protein 2 (Mrp2), which play hepatic BSP uptake and biliary excretion, respectively, in the liver were significantly reduced following the IDM treatment. In portal plasma, the levels of proinflammatory cytokines were unchanged, while the level of nitric oxide metabolites (NO2- + NO3-) increased to 6.5-fold that of the control. The time-course on IDM treatment indicated that, firstly, intestinal injury was induced, the NO level increased, and the hepatic Oatp1b2 and Mrp2 expression began to fall followed by an increase in plasma ALT. In conclusion, IDM-induced injury to the small intestine causes the hypofunction of hepatic Oatp1b2 and Mrp2 independently on the hepatic impairment, and NO arising from bowel injury may be one of key factors for it through the remote effect.
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Affiliation(s)
- Nobuhiro Fujiyama
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana Chuoku, Chiba 260-8675, Japan
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24
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Schaheen L, Patton G, Fares H. Suppression of thecup-5mucolipidosis type IV-related lysosomal dysfunction by the inactivation of an ABC transporter inC. elegans. Development 2006; 133:3939-48. [PMID: 16943270 DOI: 10.1242/dev.02575] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutations in MCOLN1, which encodes the protein mucolipin 1, result in the lysosomal storage disease mucolipidosis Type IV. Studies on human mucolipin 1 and on CUP-5, the Caenorhabditis elegans ortholog of mucolipin 1, have shown that these proteins are required for lysosome biogenesis/function. Loss of CUP-5 results in a defect in lysosomal degradation, leading to embryonic lethality. We have identified a mutation in the ABC transporter MRP-4 that rescues the degradation defect and the corresponding lethality, owing to the absence of CUP-5. MRP-4 localizes to endocytic compartments and its levels are elevated in the absence of CUP-5. These results indicate that the lysosomal degradation defect is exacerbated in some cells because of the accumulation of MRP-4 in lysosomes rather than the loss of CUP-5 per se. We also show that under some conditions, loss of MRP-4 rescues the embryonic lethality caused by the loss of the cathepsin L protease, indicating that the accumulation of ABC transporters may be a more general mechanism whereby an initial lysosomal dysfunction is more severely compromised.
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Affiliation(s)
- Lara Schaheen
- Department of Molecular and Cellular Biology, Life Sciences South Room 531, University of Arizona, Tucson, AZ 85721, USA
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Nies AT, Keppler D. The apical conjugate efflux pump ABCC2 (MRP2). Pflugers Arch 2006; 453:643-59. [PMID: 16847695 DOI: 10.1007/s00424-006-0109-y] [Citation(s) in RCA: 252] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Accepted: 05/29/2006] [Indexed: 12/14/2022]
Abstract
ABCC2 is a member of the multidrug resistance protein subfamily localized exclusively to the apical membrane domain of polarized cells, such as hepatocytes, renal proximal tubule epithelia, and intestinal epithelia. This localization supports the function of ABCC2 in the terminal excretion and detoxification of endogenous and xenobiotic organic anions, particularly in the unidirectional efflux of substances conjugated with glutathione, glucuronate, or sulfate, as exemplified by leukotriene C(4), bilirubin glucuronosides, and some steroid sulfates. The hepatic ABCC2 pump contributes to the driving forces of bile flow. Acquired or hereditary deficiency of ABCC2, the latter known as Dubin-Johnson syndrome in humans, causes an increased concentration of bilirubin glucuronosides in blood because of their efflux from hepatocytes via the basolateral ABCC3, which compensates for the deficiency in ABCC2-mediated apical efflux. In this article we provide an overview on the molecular characteristics of ABCC2 and its expression in various tissues and species. We discuss the transcriptional and posttranscriptional regulation of ABCC2 and review approaches to the functional analysis providing information on its substrate specificity. A comprehensive list of sequence variants in the human ABCC2 gene summarizes predicted and proven functional consequences, including variants leading to Dubin-Johnson syndrome.
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Affiliation(s)
- Anne T Nies
- Division of Tumor Biochemistry, German Cancer Research Center, Heidelberg, Germany.
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Cole SPC, Deeley RG. Transport of glutathione and glutathione conjugates by MRP1. Trends Pharmacol Sci 2006; 27:438-46. [PMID: 16820223 DOI: 10.1016/j.tips.2006.06.008] [Citation(s) in RCA: 264] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 04/25/2006] [Accepted: 06/19/2006] [Indexed: 11/30/2022]
Abstract
Glutathione (GSH)-conjugated xenobiotics and GSH-conjugated metabolites (e.g. the cysteinyl leukotriene C4) must be exported from the cells in which they are formed before they can be eliminated from the body or act on their cellular targets. This efflux is often mediated by the multidrug resistance protein 1 (MRP1) transporter, which also confers drug resistance to tumour cells and can protect normal cells from toxic insults. In addition to drugs and GSH conjugates, MRP1 exports GSH and GSH disulfide, and might thus have a role in cellular responses to oxidative stress. The transport of several drugs and conjugated organic anions by MRP1 requires the presence of GSH, but it is not well understood how GSH (and its analogues) enhances transport. Site-directed mutagenesis studies and biophysical analyses have provided important insights into the structural determinants of MRP1 that influence GSH and GSH conjugate binding and transport.
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Affiliation(s)
- Susan P C Cole
- Division of Cancer Biology and Genetics, Cancer Research Institute, Queen's University, Kingston, Ontario K7L 3N6, Canada.
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Rius M, Hummel-Eisenbeiss J, Hofmann AF, Keppler D. Substrate specificity of human ABCC4 (MRP4)-mediated cotransport of bile acids and reduced glutathione. Am J Physiol Gastrointest Liver Physiol 2006; 290:G640-9. [PMID: 16282361 DOI: 10.1152/ajpgi.00354.2005] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The multidrug resistance protein ABCC4 (MRP4), a member of the ATP-binding cassette superfamily, mediates ATP-dependent unidirectional efflux of organic anions out of cells. Previous studies showed that human ABCC4 is localized to the sinusoidal membrane of hepatocytes and mediates, among other substrates, the cotransport of reduced glutathione (GSH) with bile acids. In the present study, using inside-out membrane vesicles, we demonstrated that human ABCC4 in the presence of physiological concentrations of GSH has a high affinity for the taurine and glycine conjugates of the common natural bile acids as well as the unconjugated bile acid cholate. Chenodeoxycholyltaurine and chenodeoxycholylglycine were the GSH cosubstrates with the highest affinities for ABCC4, with K(m) values of 3.6 and 5.9 microM, respectively. Ursodeoxycholyltaurine and ursodeoxycholylglycine were cotransported together with GSH by ABCC4 with K(m) values of 7.8 and 12.5 microM, respectively, but no transport of ursodeoxycholate and deoxycholate was observed. The simultaneous transport of labeled GSH and cholyltaurine or cholylglycine was demonstrated in double-labeled cotransport experiments with a bile acid-to-GSH ratio of approximately 1:22. K(m) values of the bile acids for ABCC4 were in a range similar to those reported for the canalicular bile salt export pump ABCB11. Under physiological conditions, the sinusoidal ABCC4 may compete with canalicular ABCB11 for bile acids and thereby play a key role in determining the hepatocyte concentration of bile acids. In cholestatic conditions, ABCC4 may become a key pathway for efflux of bile acids from hepatocytes into blood.
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Affiliation(s)
- Maria Rius
- Division of Tumor Biochemistry, German Cancer Research Center, Heidelberg, Germany.
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28
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Borst P, Zelcer N, van de Wetering K, Poolman B. On the putative co-transport of drugs by multidrug resistance proteins. FEBS Lett 2005; 580:1085-93. [PMID: 16386247 DOI: 10.1016/j.febslet.2005.12.039] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2005] [Revised: 12/09/2005] [Accepted: 12/13/2005] [Indexed: 10/25/2022]
Abstract
Experiments with multidrug resistance-associated protein 1 (MRP1) showed 10-years ago that transport of vincristine (VCR) by MRP1 could be stimulated by GSH, and transport of GSH by VCR. Since then many examples of stimulated transport have been reported for MRP1, 2, 3, 4 and 8. We discuss here three models to explain stimulated transport. We favour a model in which a large promiscuous binding site can bind more than one ligand, allowing cooperative/competitive interactions between ligands within the binding site. We conclude that there is no unambiguous proof for co-transport of two different ligands by MRPs, but that cross-stimulated transport can explain the published data.
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Affiliation(s)
- P Borst
- Center of Biomedical Genetics, Division of Molecular Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
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Bortfeld M, Rius M, König J, Herold-Mende C, Nies AT, Keppler D. Human multidrug resistance protein 8 (MRP8/ABCC11), an apical efflux pump for steroid sulfates, is an axonal protein of the CNS and peripheral nervous system. Neuroscience 2005; 137:1247-57. [PMID: 16359813 DOI: 10.1016/j.neuroscience.2005.10.025] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 10/04/2005] [Accepted: 10/07/2005] [Indexed: 11/24/2022]
Abstract
Dehydroepiandrosterone 3-sulfate and other neurosteroids are synthesized in the CNS and peripheral nervous system where they may modulate neuronal excitability by interacting with ligand-gated ion channels. For this modulatory activity, neurosteroids have to be locally released from either neurons or glial cells. We here identify the integral membrane protein ABCC11 (multidrug resistance protein 8) as an ATP-dependent efflux pump for steroid sulfates, including dehydroepiandrosterone 3-sulfate, and localize it to axons of the human CNS and peripheral nervous system. ABCC11 mRNA was detected in human brain by real-time polymerase chain reaction. Antibodies raised against ABCC11 served to detect the protein in brain by immunoblotting and immunofluorescence microscopy. ABCC11 was preferentially found in the white matter of the brain and co-localized with neurofilaments indicating that it is an axonal protein. Additionally, ABCC11 was localized to axons of the peripheral nervous system. For functional studies, ABCC11 was expressed in polarized Madin-Darby canine kidney cells where it was sorted to the apical membrane. This apical sorting is in accordance with the localization of ABCC11 to the axonal membrane of neurons. Inside-out plasma membrane vesicles containing recombinant ABCC11 mediated ATP-dependent transport of dehydroepiandrosterone 3-sulfate with a Km value of 21 microM. This transport function together with the localization of the ABCC11 protein in vicinity to GABAA receptors is consistent with a role of ABCC11 in dehydroepiandrosterone 3-sulfate release from neurons to sites of dehydroepiandrosterone 3-sulfate-mediated receptor modulation. Our findings may provide a basis for the characterization of mutations in the human ABCC11 gene and their linkage with neurological disorders.
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Affiliation(s)
- M Bortfeld
- Division of Tumor Biochemistry, German Cancer Research Center, University of Heidelberg, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
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Ritter CA, Jedlitschky G, Meyer zu Schwabedissen H, Grube M, Köck K, Kroemer HK. Cellular export of drugs and signaling molecules by the ATP-binding cassette transporters MRP4 (ABCC4) and MRP5 (ABCC5). Drug Metab Rev 2005; 37:253-78. [PMID: 15747503 DOI: 10.1081/dmr-200047984] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Like other members of the multidrug resistance protein (MRP)/ABCC subfamily of ATP-binding cassette transporters, MRP4 (ABCC4) and MRP5 (ABCC5) are organic anion transporters. They have, however, the outstanding ability to transport nucleotides and nucleotide analogs. In vitro experiments using drug-selected or -transfected cells indicated that these transport proteins, when overexpressed, can lower the intracellular concentration of nucleoside/nucleotide analogs, such as the antiviral compounds PMEA (9-(2-phosphonylmethoxyethyl)adenine) or ganciclovir, and of anticancer nucleobase analogs, such as 6-mercaptopurine, after their conversion into the respective nucleotides. This may lead to an impaired ability of these compounds to inhibit virus replication or cell proliferation. It remains to be tested whether antiviral or anticancer chemotherapy based on nucleobase, nucleoside, or nucleotide precursors can be modulated by inhibition of MRP4 and MRP5. MRP4 also seems to be able to mediate the transport of conjugated steroids, prostaglandins, and glutathione. Furthermore, cyclic nucleotides (cyclic adenosine monophosphate and cyclic guanine monophosphate) are exported from cells by MRP4 and MRP5. This may modulate the intracellular concentration of these important mediators, besides the action of phosphodiesterases, as well as provide extracellular nucleotides for a possible paracrine action. In this line, tissue distribution and subcellular localization of MRP4 and MRP5 specifically in smooth muscle cells (MRP5), platelet-dense granules (MRP4), and nervous cells (MRP4 and MRP5), besides the capillary endothelium, point not only to a possible function of these transporters as exporters in cellular defense, but also to a physiological function in signaling processes.
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Affiliation(s)
- Christoph A Ritter
- Department of Pharmacology, Peter Holtz Research Center of Pharmacology and Experimental Therapeutics, Ernst-Moritz-Arndt University Greifswald, Greifswald, Germany
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Batrakova EV, Li S, Li Y, Alakhov VY, Kabanov AV. Effect of pluronic P85 on ATPase activity of drug efflux transporters. Pharm Res 2005; 21:2226-33. [PMID: 15648254 PMCID: PMC2677181 DOI: 10.1007/s11095-004-7675-5] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE Pluronic block copolymers are potent sensitizers of multi-drug resistant (MDR) cancer cells. The sensitization effect by Pluronics is a result of two processes acting in concert: i) intracellular ATP depletion, and ii) inhibition of ATPase activity of drug efflux proteins. This work characterizes effects of Pluronic P85 on ATPase activities of Pgp, MRP1, and MRP2 drug efflux transport proteins and interaction of these proteins with their substrates, vinblastine, and leucotriene C4. METHODS Using membranes overexpressing Pgp, MRP1, and MRP2, the current study evaluates effects of Pluronic P85 (P85) on the kinetic parameters (Vmax, Km, Vmax/Km) of ATP hydrolysis by these ATPases. RESULTS The decreases in the maximal reaction rates (Vmax) and increases in apparent Michaelis constants (Km) for these transporters in the presence of various concentrations of P85 were observed. The mechanism of these effects may involve i) conformational changes of the transporter due to membrane fluidization and/or ii) nonspecific steric hindrance of the drug-binding sites by P85 chains embedded into cellular membranes. The extent of these alterations was increased in the row MRP1 < MRP2 << Pgp. CONCLUSIONS These data suggest that there are unifying pathways for the inhibition of Pgp and MRPs by the block copolymer. However, the effect of P85 on Pgp ATPase activity is considerably greater compared with the effects on MRP1 and MRP2 ATPases. This may be a reason for greater inhibitory effects of Pluronic in Pgp- compared with MRP-overexpressing cells.
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Affiliation(s)
- Elena V. Batrakova
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 985830 Nebraska Medical Center, Omaha, Nebraska 68198-5830, USA
| | - Shu Li
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 985830 Nebraska Medical Center, Omaha, Nebraska 68198-5830, USA
| | - Yili Li
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 985830 Nebraska Medical Center, Omaha, Nebraska 68198-5830, USA
| | - Valery Yu. Alakhov
- Supratek Pharma Inc., 215, boulevard Bouchard #1315, Dorval, Quebec, Canada H9S 1A9
| | - Alexander V. Kabanov
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 985830 Nebraska Medical Center, Omaha, Nebraska 68198-5830, USA
- To whom correspondence should be addressed. (e-mail: )
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Fardel O, Jigorel E, Le Vee M, Payen L. Physiological, pharmacological and clinical features of the multidrug resistance protein 2. Biomed Pharmacother 2005; 59:104-14. [PMID: 15795103 DOI: 10.1016/j.biopha.2005.01.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Indexed: 12/17/2022] Open
Abstract
Multidrug resistance protein 2 (MRP2, ABCC2) is a drug efflux pump belonging to the ATP-binding cassette (ABC) transporter superfamily. MRP2 is present predominantly at the biliary pole of hepatocytes and is also expressed in the kidney and intestine. It plays a major role in hepato-biliary elimination of many structurally diverse xenobiotics, including organic anions and drug conjugates, and therefore most likely contributes to pharmacokinetic parameters of these compounds. MRP2 also handles endogenous molecules such as bilirubin, and its overexpression has been shown to confer a multidrug resistance phenotype to tumoral cells. MRP2 expression can be regulated by endogenous substances such as inflammatory cytokines and biliary acids. The MRP2 levels and activity can also be affected by a large panel of xenobiotics, including chemopreventive agents and ligands of the pregnane X receptor, which may be a potential source of drug-drug interactions and drug adverse effects. MRP2 appears therefore as one of the major drug efflux pumps of the organism, whose functional and regulatory features are important to consider, notably for drug disposition.
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Affiliation(s)
- Olivier Fardel
- Inserm U620, Faculté de Pharmacie, 2 Avenue Professeur Leon Bernard, 35043 Rennes, France.
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Nies AT, Jedlitschky G, König J, Herold-Mende C, Steiner HH, Schmitt HP, Keppler D. Expression and immunolocalization of the multidrug resistance proteins, MRP1-MRP6 (ABCC1-ABCC6), in human brain. Neuroscience 2005; 129:349-60. [PMID: 15501592 DOI: 10.1016/j.neuroscience.2004.07.051] [Citation(s) in RCA: 263] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2004] [Indexed: 11/16/2022]
Abstract
Multidrug resistance proteins (MRPs, symbol ABCC) are membrane glycoproteins that mediate the ATP-dependent export of organic anions, including cytotoxic and antiviral drugs, from cells. To identify MRP family members possibly involved in the intrinsic resistance of human brain to cytotoxic and antiviral drugs, we analyzed the expression and localization of MRP1-MRP6 in rapidly frozen perilesional samples of several regions of adult human brain obtained during neurosurgery. Quantitative polymerase chain reaction analysis showed expression of MRP1, MRP2, MRP3, MRP4, and MRP5 mRNA, whereas MRP6 mRNA was below detectability. However, immunofluorescence microscopy of cryosections from human brain showed no reactivity for the MRP2 or MRP3 proteins. The proteins MRP1, MRP4, and MRP5 were clearly localized by confocal laser scanning microscopy to the luminal side of brain capillary endothelial cells. The MRP4 and MRP5 proteins were also detected in astrocytes of the subcortical white matter. Notably, MRP5 protein was present in pyramidal neurons. MRP proteins may, thus, contribute to the cellular efflux of endogenous anionic glutathione or glucuronate conjugates (substrates for MRP1), cyclic nucleotides (substrates for MRP4 and MRP5), or glutathione (co-substrate for MRP1 and MRP4); in addition, they may play an important role in the resistance of the brain to several cytotoxic and antiviral drugs.
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Affiliation(s)
- A T Nies
- Division of Tumor Biochemistry, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
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Kawano T, Matsuse H, Kondo Y, Machida I, Saeki S, Tomari S, Mitsuta K, Fukushima C, Obase Y, Shimoda T, Kohno S. Tacrolimus reduces urinary excretion of leukotriene E(4) and inhibits aspirin-induced asthma to threshold dose of aspirin. J Allergy Clin Immunol 2005; 114:1278-81. [PMID: 15577823 DOI: 10.1016/j.jaci.2004.09.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The exact mechanism of aspirin-induced asthma is not clear. It has been postulated that precipitation of asthma attacks by aspirin is linked to inhibition of COX activity and massive release of cysteinyl leukotriene into the airway. Tacrolimus, a macrolide-derived immunosuppressant, is used for immunosuppression in organ transplantation and also for allergic diseases such as atopic dermatitis. OBJECTIVE We evaluated the effects of tacrolimus in aspirin-induced asthma by using a double-blind, crossover study design. METHODS Twelve patients with aspirin-induced asthma (male:female, 3:9; mean age +/- SD, 36.7 +/- 7.2 years) received either tacrolimus (0.1 mg/kg) or placebo 2 hours before the threshold dose of oral aspirin. RESULTS In the placebo arm, oral aspirin significantly decreased FEV 1 concomitant with significant increases in sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. Tacrolimus significantly inhibited bronchoconstriction and abrogated aspirin-induced increase in both sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. CONCLUSION The current study suggested that tacrolimus inhibited bronchoconstriction to a threshold dose of aspirin by inhibition of cysteinyl leukotriene excretion.
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Affiliation(s)
- Tetsuya Kawano
- Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki, Japan
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Ciccarelli R, D'Alimonte I, Santavenere C, D'Auro M, Ballerini P, Nargi E, Buccella S, Nicosia S, Folco G, Caciagli F, Di Iorio P. Cysteinyl-leukotrienes are released from astrocytes and increase astrocyte proliferation and glial fibrillary acidic protein via cys-LT1 receptors and mitogen-activated protein kinase pathway. Eur J Neurosci 2004; 20:1514-24. [PMID: 15355318 DOI: 10.1111/j.1460-9568.2004.03613.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Cysteinyl-leukotrienes (cys-LTs), potent mediators in inflammatory diseases, are produced by nervous tissue, but their cellular source and role in the brain are not very well known. In this report we have demonstrated that rat cultured astrocytes express the enzymes (5'-lipoxygenase and LTC(4) synthase) required for cys-LT production, and release cys-LTs in resting condition and, to a greater extent, in response to calcium ionophore A23187, 1 h combined oxygen-glucose deprivation or 2-methyl-thioATP, a selective P2Y(1)/ATP receptor agonist. MK-886, a LT synthesis inhibitor, prevented basal and evoked cys-LT release. In addition, 2-methyl-thioATP-induced cys-LT release was abolished by suramin, a P2 receptor antagonist, or by inhibitors of ATP binding cassette proteins involved in cys-LT release. We also showed that astrocytes express cys-LT(1) and not cys-LT(2) receptors. The stimulation of these receptors by LTD(4) activated the mitogen-activated protein kinase (MAPK) pathway. This effect was: (i) insensitive to inhibitors of receptor-coupled Gi protein (pertussis toxin) or tyrosine kinase receptors (genistein); (ii) abolished by MK-571, a cys-LT(1) selective receptor antagonist, or PD98059, a MAPK inhibitor; (iii) reduced by inhibitors of calcium/calmodulin-dependent kinase II (KN-93), Ca(2+)-dependent and -independent (GF102903X) or Ca(2+)-dependent (Gö6976) protein kinase C isoforms. LTD(4) also increased astrocyte proliferation and glial fibrillary acidic protein content, which are considered hallmarks of reactive astrogliosis. Both effects were counteracted by cell pretreatment with MK-571 or PD98059. Thus, cys-LTs released from astrocytes might play an autocrine role in the induction of reactive astrogliosis that, in brain injuries, contributes to the formation of a reparative glial scar.
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Affiliation(s)
- Renata Ciccarelli
- Department of Biomedical Sciences, Section of Pharmacology, Medical School, G. D'Annunzio University of Chieti, Chieti, Italy.
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Borst P, Balzarini J, Ono N, Reid G, de Vries H, Wielinga P, Wijnholds J, Zelcer N. The potential impact of drug transporters on nucleoside-analog-based antiviral chemotherapy. Antiviral Res 2004; 62:1-7. [PMID: 15026196 DOI: 10.1016/j.antiviral.2003.11.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2003] [Revised: 10/23/2003] [Accepted: 11/11/2003] [Indexed: 11/17/2022]
Abstract
Several ATP-binding cassette (ABC) transporters can transport drugs out of cells against steep concentration gradients resulting in resistance to the drugs transported. Recent work has shown that at least three members of the family of human Multidrug Resistance-associated Proteins (MRPs), MRP4, 5 and 8, are able to transport some nucleoside-monophosphate analogs. This can result in resistance to the base, nucleoside or nucleotide precursors of these results, at least in cell lines with high levels of transporter. The affinity of these transporters for the nucleotide analogs studied thus far is relatively low (millimolar rather than micromolar), and this limits their potential impact on the resistance. We briefly review how ABC transporters in general, and MRPs in particular, could affect the disposition and cellular accumulation of antiviral compounds.
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Affiliation(s)
- P Borst
- Division of Molecular Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.
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37
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Dazert P, Meissner K, Vogelgesang S, Heydrich B, Eckel L, Böhm M, Warzok R, Kerb R, Brinkmann U, Schaeffeler E, Schwab M, Cascorbi I, Jedlitschky G, Kroemer HK. Expression and localization of the multidrug resistance protein 5 (MRP5/ABCC5), a cellular export pump for cyclic nucleotides, in human heart. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 163:1567-77. [PMID: 14507663 PMCID: PMC1868287 DOI: 10.1016/s0002-9440(10)63513-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The multidrug resistance protein 5 (MRP5/ABCC5) has been recently identified as cellular export pump for cyclic nucleotides with 3',5'-cyclic GMP (cGMP) as a high-affinity substrate. In view of the important role of cGMP for cardiovascular function, expression of this transport protein in human heart is of relevance. We analyzed the expression and localization of MRP5 in human heart [21 auricular (AS) and 15 left ventricular samples (LV) including 5 samples of dilated and ischemic cardiomyopathy]. Quantitative real-time polymerase chain reaction normalized to beta-actin revealed expression of the MRP5 gene in all samples (LV, 38.5 +/- 12.9; AS, 12.7 +/- 5.6; P < 0.001). An MRP5-specific polyclonal antibody detected a glycoprotein of approximately 190 kd in crude cell membrane fractions from these samples. Immunohistochemistry with the affinity-purified antibody revealed localization of MRP5 in cardiomyocytes as well as in cardiovascular endothelial and smooth muscle cells. Furthermore, we could detect MRP5 and ATP-dependent transport of [(3)H]cGMP in sarcolemma vesicles of human heart. Quantitative analysis of the immunoblots indicated an interindividual variability with a higher expression of MRP5 in the ischemic (104 +/- 38% of recombinant MRP5 standard) compared to normal ventricular samples (53 +/- 36%, P < 0.05). In addition, we screened genomic DNA from our samples for 20 single-nucleotide polymorphisms in the MRP5 gene. These results indicate that MRP5 is localized in cardiac and cardiovascular myocytes as well as endothelial cells with increased expression in ischemic cardiomyopathy. Therefore, MRP5-mediated cellular export may represent a novel, disease-dependent pathway for cGMP removal from cardiac cells.
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Affiliation(s)
- Peter Dazert
- Department of Pharmacology, Peter Holtz Research Center of Pharmacology and Experimental Therapeutics, Ernst-Moritz-Arndt-University, Greifswald, Germany
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Zelcer N, Huisman MT, Reid G, Wielinga P, Breedveld P, Kuil A, Knipscheer P, Schellens JHM, Schinkel AH, Borst P. Evidence for two interacting ligand binding sites in human multidrug resistance protein 2 (ATP binding cassette C2). J Biol Chem 2003; 278:23538-44. [PMID: 12702717 DOI: 10.1074/jbc.m303504200] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Multidrug resistance protein 2 (MRP2) belongs to the ATP binding cassette family of transporters. Its substrates include organic anions and anticancer drugs. We have used transport assays with vesicles derived from Sf9 insect cells overproducing MRP2 to study the interactions of drugs, organic anions, and bile acids with three MRP2 substrates: estradiol-17-beta-d-glucuronide (E217betaG), methotrexate, and glutathione-S-dinitrophenol. Complex inhibition and stimulation patterns were obtained, different from those observed with the related transporters MRP1 and MRP3. In contrast to a previous report, we found that the rate of E217betaG transport by MRP2 increases sigmoidally with substrate concentration indicative of homotropic cooperativity. Half-maximal transport was obtained at 120 microm E217betaG, in contrast to values < 20 microm for MRP1 and 3. MRP2 stimulators, such as indomethacin and sulfanitran, strongly increased the affinity of MRP2 for E217betaG (half-maximal transport rates at 65 and 16 microm E217betaG, respectively) and shifted the sigmoidal dependence of transport rate on substrate concentration to a more hyperbolic one, without substantially affecting the maximal transport rate. Sulfanitran also stimulated MRP2 activity in cells, i.e. the transport of saquinavir through monolayers of Madin-Darby canine kidney II cells. Some compounds that stimulate E217betaG transport, such as penicillin G or pantoprazole, are not detectably transported by MRP2, suggesting that they allosterically stimulate transport without being cotransported with E217betaG. We propose that MRP2 contains two similar but nonidentical ligand binding sites: one site from which substrate is transported and a second site that regulates the affinity of the transport site for the substrate.
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Affiliation(s)
- Noam Zelcer
- Division of Molecular Biology and Center of Biomedical Genetics, Netherlands Cancer Institute, Amsterdam, The Netherlands
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Tornhamre S, Stenke L, Granzelius A, Sjölinder M, Näsman-Glaser B, Roos C, Widell S, Lindgren JA. Inverse relationship between myeloid maturation and leukotriene C4 synthase expression in normal and leukemic myelopoiesis-consistent overexpression of the enzyme in myeloid cells from patients with chronic myeloid leukemia. Exp Hematol 2003; 31:122-30. [PMID: 12591277 DOI: 10.1016/s0301-472x(02)01026-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Leukotriene (LT) C(4) synthase (LTC(4)S) is the key enzyme in the biosynthesis of LTC(4), which has been reported to stimulate the growth of human myeloid progenitor cells and is specifically overproduced in chronic myeloid leukemia (CML). The aim of this study was to clarify the expression of LTC(4)S during normal and leukemic myelopoiesis and to investigate the correlation between abnormal LTC(4)S expression in CML myeloid cells and the activity of the disease-specific tyrosine kinase p210 BCR-ABL. MATERIALS AND METHODS Immature and mature myeloid cell subpopulations were isolated with magnetic cell sorting from healthy volunteer bone marrow (n = 11) and CML patient peripheral blood (n = 8), respectively. The cells were subjected to analysis of LTC(4)S protein expression and activity. Expression of LTC(4)S was investigated in CD16(+) neutrophils from CML patients before and after 1 month of medication with imatinib mesylate (STI571), which is a specific inhibitor of p210 BCR-ABL. RESULTS Among normal cells, the highest enzyme activity was observed in the most immature, CD34(+) progenitor cell-enriched and CD15(+) myelocyte-enriched fractions. Subsequently, LTC(4)S activity decreased with increasing maturity, with only negligible amounts of LTC(4) produced in CD16(+) neutrophils. LTC(4)S was expressed at the protein level in the immature myeloid cell fractions but not in CD16(+) cells. In CML cells, LTC(4)S activity and expression were consistently elevated. Thus, the CML CD34(+) and CD15(+) cell fractions, as well as the CD11b(+) myelocyte/metamyelocyte-enriched fractions, produced 6 to 10 times as much LTC(4) as the corresponding normal cells. Again, enzyme expression was highest in the most immature cells, although evident LTC(4)S expression and activity remained in CML CD16(+) neutrophils. Interestingly, treatment of five CML patients with imatinib mesylate down-regulated the abnormal neutrophil LTC(4)S expression and activity. CONCLUSIONS Expression of LTC(4)S in immature myelopoid cells is in line with a role for this enzyme in myelopoiesis. In addition, consistent overexpression of LTC(4)S in CML and the correlation to p210 BCR-ABL activity suggests that LTC(4)S may be involved in leukemic pathogenesis.
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MESH Headings
- Antigens, CD34
- Benzamides
- Case-Control Studies
- Cell Differentiation/drug effects
- Gene Expression Regulation, Leukemic/drug effects
- Glutathione Transferase/genetics
- Glutathione Transferase/physiology
- Humans
- Imatinib Mesylate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Lewis X Antigen
- Myeloid Cells/cytology
- Myeloid Cells/enzymology
- Myelopoiesis/drug effects
- Myelopoiesis/physiology
- Neutrophils/enzymology
- Neutrophils/pathology
- Piperazines/pharmacology
- Piperazines/therapeutic use
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Receptors, IgG
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Affiliation(s)
- Susanne Tornhamre
- Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Scheele Laboratory, Karolinska Institutet, S-171 77 Stockholm, Sweden.
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Dantzig AH, de Alwis DP, Burgess M. Considerations in the design and development of transport inhibitors as adjuncts to drug therapy. Adv Drug Deliv Rev 2003; 55:133-50. [PMID: 12535578 DOI: 10.1016/s0169-409x(02)00175-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
With the realization of the importance of drug efflux transporters in disease processes and treatment, development of inhibitors to these transporters has been sought for use as adjuncts to therapy. To date, inhibitors that have been best studied are modulators of P-glycoprotein, a transporter important in the removal of anticancer agents from cells and overexpression of this transporter results in multidrug resistance. There is a delicate balance between efficacy and toxicity. This review summarizes key learning points in the development of P-glycoprotein inhibitors. Topics covered include specificity of the inhibitor for the target transporter, effect on metabolism of coadministered drugs, pharmacokinetic interactions, toxicity and the salient features needed for efficacy. These points will have general application to the development of inhibitors of transporters.
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Affiliation(s)
- Anne H Dantzig
- Cancer Research, Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285, USA.
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Hirrlinger J, König J, Dringen R. Expression of mRNAs of multidrug resistance proteins (Mrps) in cultured rat astrocytes, oligodendrocytes, microglial cells and neurones. J Neurochem 2002; 82:716-9. [PMID: 12153495 DOI: 10.1046/j.1471-4159.2002.01082.x] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Multidrug resistance proteins (Mrps) are ATP-driven export pumps that mediate the export of organic anions from cells. So far only little information is available on expression and physiological functions of Mrps in brain. The expression of mRNAs of six Mrp paralogs in rat brain, as well as in rat cultures enriched for neurones, astrocytes, oligodendrocytes and microglial cells, was studied by qualitative and semiquantitative RT-PCR analysis. In adult rat brain as well as in neural cell cultures the mRNAs coding for Mrp1, Mrp3, Mrp4 and Mrp5 were detected. Semiquantitative analysis revealed that the mRNAs coding for Mrp1 and Mrp5 were more abundant in the four cell culture types than mRNAs of the other Mrps. mRNAs coding for Mrp3 and Mrp4 were found at significant levels in cultured astrocytes and microglial cells, whereas cultures of neurones and oligodendrocytes contained only marginal quantities of these mRNAs. Putative physiological functions of Mrps in brain cells are discussed.
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