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Lundquist P, Artursson P. Oral absorption of peptides and nanoparticles across the human intestine: Opportunities, limitations and studies in human tissues. Adv Drug Deliv Rev 2016; 106:256-276. [PMID: 27496705 DOI: 10.1016/j.addr.2016.07.007] [Citation(s) in RCA: 312] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/02/2016] [Accepted: 07/08/2016] [Indexed: 12/23/2022]
Abstract
In this contribution, we review the molecular and physiological barriers to oral delivery of peptides and nanoparticles. We discuss the opportunities and predictivity of various in vitro systems with special emphasis on human intestine in Ussing chambers. First, the molecular constraints to peptide absorption are discussed. Then the physiological barriers to peptide delivery are examined. These include the gastric and intestinal environment, the mucus barrier, tight junctions between epithelial cells, the enterocytes of the intestinal epithelium, and the subepithelial tissue. Recent data from human proteome studies are used to provide information about the protein expression profiles of the different physiological barriers to peptide and nanoparticle absorption. Strategies that have been employed to increase peptide absorption across each of the barriers are discussed. Special consideration is given to attempts at utilizing endogenous transcytotic pathways. To reliably translate in vitro data on peptide or nanoparticle permeability to the in vivo situation in a human subject, the in vitro experimental system needs to realistically capture the central aspects of the mentioned barriers. Therefore, characteristics of common in vitro cell culture systems are discussed and compared to those of human intestinal tissues. Attempts to use the cell and tissue models for in vitro-in vivo extrapolation are reviewed.
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Affiliation(s)
- P Lundquist
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
| | - P Artursson
- Department of Pharmacy, Uppsala University, Box 580, SE-752 37 Uppsala, Sweden.
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2
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Dedhia PH, Bertaux-Skeirik N, Zavros Y, Spence JR. Organoid Models of Human Gastrointestinal Development and Disease. Gastroenterology 2016; 150:1098-1112. [PMID: 26774180 PMCID: PMC4842135 DOI: 10.1053/j.gastro.2015.12.042] [Citation(s) in RCA: 171] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 12/21/2022]
Abstract
We have greatly advanced our ability to grow a diverse range of tissue-derived and pluripotent stem cell-derived gastrointestinal (GI) tissues in vitro. These systems, broadly referred to as organoids, have allowed the field to move away from the often nonphysiological, transformed cell lines that have been used for decades in GI research. Organoids are derived from primary tissues and have the capacity for long-term growth. They contain varying levels of cellular complexity and physiological similarity to native organ systems. We review the latest discoveries from studies of tissue-derived and pluripotent stem cell-derived intestinal, gastric, esophageal, liver, and pancreatic organoids. These studies have provided important insights into GI development, tissue homeostasis, and disease and might be used to develop personalized medicines.
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Affiliation(s)
- Priya H. Dedhia
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI 48109, USA,Center for Organogenesis, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Nina Bertaux-Skeirik
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Yana Zavros
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, Ohio.
| | - Jason R. Spence
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109, USA,Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA,Center for Organogenesis, University of Michigan Medical School, Ann Arbor, MI 48109, USA,Authors for Correspondence: Jason R. Spence – , Twitter: @TheSpenceLab, Yana Zavros –
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3
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Bergström CA, Holm R, Jørgensen SA, Andersson SB, Artursson P, Beato S, Borde A, Box K, Brewster M, Dressman J, Feng KI, Halbert G, Kostewicz E, McAllister M, Muenster U, Thinnes J, Taylor R, Mullertz A. Early pharmaceutical profiling to predict oral drug absorption: Current status and unmet needs. Eur J Pharm Sci 2014; 57:173-99. [DOI: 10.1016/j.ejps.2013.10.015] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 10/17/2013] [Accepted: 10/27/2013] [Indexed: 01/17/2023]
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4
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Artursson P, Palm K, Luthman K. Caco-2 monolayers in experimental and theoretical predictions of drug transport. Adv Drug Deliv Rev 2012. [DOI: 10.1016/j.addr.2012.09.005] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Zaki NM, Artursson P, Bergström CAS. A modified physiological BCS for prediction of intestinal absorption in drug discovery. Mol Pharm 2010; 7:1478-87. [PMID: 20734997 DOI: 10.1021/mp100124f] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In this study, the influence of physiologically relevant media on the compound position in a biopharmaceutical classification system (BCS) which resembled the intestinal absorption was investigated. Both solubility and permeability limited compounds (n = 22) were included to analyze the importance of each of these on the final absorption. Solubility was determined in three different dissolution media, phosphate buffer pH 6.5 (PhB 6.5), fasted state simulated intestinal fluid (FaSSIF), and fed state simulated intestinal fluid (FeSSIF) at 37 °C, and permeability values were determined using the 2/4/A1 cell line. The solubility data and membrane permeability values were used for sorting the compounds into a BCS modified to reflect the fasted and fed state. Three of the seven compounds sorted as BCS II in PhB 6.5 (high permeability, low solubility) changed their position to BCS I when dissolved in FaSSIF and/or FeSSIF (high permeability, high solubility). These were low dosed (20 mg or less) lipophilic molecules displaying solvation limited solubility. In contrast, compounds having solid-state limited solubility had a minor increase in solubility when dissolved in FaSSIF and/or FeSSIF. Although further studies are needed to enable general cutoff values, our study indicates that low dosed BCS Class II compounds which have solubility normally restricted by poor solvation may behave as BCS Class I compounds in vivo. The large series of compounds investigated herein reveals the importance of investigating solubility and dissolution under physiologically relevant conditions in all stages of the drug discovery process to push suitable compounds forward, to select proper formulations, and to reduce the risk of food effects.
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Affiliation(s)
- Noha M Zaki
- The Uppsala University Drug Optimization and Pharmaceutical Profiling Platform, Department of Pharmacy, Uppsala University, Biomedical Center P.O. Box 580, SE-751 23 Uppsala, Sweden
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Sugano K, Kansy M, Artursson P, Avdeef A, Bendels S, Di L, Ecker GF, Faller B, Fischer H, Gerebtzoff G, Lennernaes H, Senner F. Coexistence of passive and carrier-mediated processes in drug transport. Nat Rev Drug Discov 2010; 9:597-614. [PMID: 20671764 DOI: 10.1038/nrd3187] [Citation(s) in RCA: 435] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The permeability of biological membranes is one of the most important determinants of the pharmacokinetic processes of a drug. Although it is often accepted that many drug substances are transported across biological membranes by passive transcellular diffusion, a recent hypothesis speculated that carrier-mediated mechanisms might account for the majority of membrane drug transport processes in biological systems. Based on evidence of the physicochemical characteristics and of in vitro and in vivo findings for marketed drugs, as well as results from real-life discovery and development projects, we present the view that both passive transcellular processes and carrier-mediated processes coexist and contribute to drug transport activities across biological membranes.
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Affiliation(s)
- Kiyohiko Sugano
- Pfizer, Research Formulation, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, UK.
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7
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Ungell A, Artursson P. An Overview of Caco‐2 and Alternatives for Prediction of Intestinal Drug Transport and Absorption. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/9783527623860.ch7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Maheshwari A, Kurundkar AR, Shaik SS, Kelly DR, Hartman Y, Zhang W, Dimmitt R, Saeed S, Randolph DA, Aprahamian C, Datta G, Ohls RK. Epithelial cells in fetal intestine produce chemerin to recruit macrophages. Am J Physiol Gastrointest Liver Physiol 2009; 297:G1-G10. [PMID: 19443732 PMCID: PMC2711762 DOI: 10.1152/ajpgi.90730.2008] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Macrophages are first seen in the fetal intestine at 11-12 wk and rapidly increase in number during the 12- to 22-wk period of gestation. The development of macrophage populations in the fetal intestine precedes the appearance of lymphocytes and neutrophils and does not require the presence of dietary or microbial antigens. In this study, we investigated the role of chemerin, a recently discovered, relatively selective chemoattractant for macrophages, in the recruitment of macrophage precursors to the fetal intestine. Chemerin mRNA/protein expression was measured in jejunoileal tissue from 10- to 24-wk human fetuses, neonates operated for intestinal obstruction, and adults undergoing bariatric surgery. The expression of chemerin in intestinal epithelial cells (IECs) was confirmed by using cultured primary IECs and IEC-like cell lines in vitro. The regulatory mechanisms involved in chemerin expression were investigated by in silico and immunolocalization techniques. IECs in the fetal, but not mature, intestine express chemerin. Chemerin expression peaked in the fetal intestine at 20-24 wk and then decreased to original low levels by full term. During the 10- to 24-wk period, chemerin accounted for most of the macrophage chemotactic activity of cultured fetal IECs. The maturational changes in chemerin expression correlated with the expression of retinoic acid receptor-beta in the intestine. Chemerin is an important mediator of epithelial-macrophage cross talk in the fetal/premature, but not in the mature, intestine. Understanding the regulation of the gut macrophage pool is an important step in development of novel strategies to boost mucosal immunity in premature infants and other patient populations at risk of microbial translocation.
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Affiliation(s)
- Akhil Maheshwari
- Pediatrics/Neonatology, Univ. of Alabama at Birmingham, VH648C, 1670 Univ. Blvd., Birmingham, AL 35294, USA.
| | - Ashish R. Kurundkar
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Sadiq S. Shaik
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - David R. Kelly
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Yolanda Hartman
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Wei Zhang
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Reed Dimmitt
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Shehzad Saeed
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - David A. Randolph
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Charles Aprahamian
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Geeta Datta
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
| | - Robin K. Ohls
- Departments of Pediatrics, Cell Biology, Pathology, Surgery, and Internal Medicine, University of Alabama at Birmingham (UAB), Birmingham, Alabama; Translational Research in Normal and Disordered Development (TReNDD) Program, UAB Department of Pediatrics; and Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico
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Korjamo T, Honkakoski P, Toppinen MR, Niva S, Reinisalo M, Palmgrén JJ, Mönkkönen J. Absorption properties and P-glycoprotein activity of modified Caco-2 cell lines. Eur J Pharm Sci 2005; 26:266-79. [PMID: 16111871 DOI: 10.1016/j.ejps.2005.06.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2004] [Revised: 04/28/2005] [Accepted: 06/21/2005] [Indexed: 10/25/2022]
Abstract
Caco-2 cell line is extensively used as an in vitro model in studying small intestinal absorption but it lacks proper expression of efflux pumps and cytochrome P450 enzymes that are involved in absorption and first pass metabolism of drugs. We created two novel Caco-2 cell lines expressing orphan nuclear receptors pregnane X receptor and constitutive androstane receptor that regulate many genes involved in xenobiotic metabolism. We conducted a systematic study on expression of some metabolic genes, P-glycoprotein activity and absorption properties of several drugs with these new cell lines and previously described modified Caco-2 cell lines (MDR1 transfection, vincristine treatment and 1alpha,25-dihydroxyvitamin D3 treatment). A short culture time medium was also included in the study. Most modified cell lines formed tight differentiated monolayers. MDR1, CYP2C9 and CYP3A4 genes were upregulated in some cell lines. Elevated P-glycoprotein activities were observed by calcein-AM uptake experiments but this did not affect significantly the permeability of selected P-glycoprotein substrates. Some cell lines had similar passive and active permeability properties to Caco/WT cells while in few cell lines these were altered. Passive transcellular permeability was modestly elevated in all modified cell lines. In addition, several compounds showed pH-dependent permeability properties.
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Affiliation(s)
- Timo Korjamo
- Department of Pharmaceutics, University of Kuopio, Harjulantie 1, P.O. Box 1627, FI-70211 Kuopio, Finland.
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Nagahara N, Tavelin S, Artursson P. Contribution of the paracellular route to the pH-dependent epithelial permeability to cationic drugs. J Pharm Sci 2005; 93:2972-84. [PMID: 15459946 DOI: 10.1002/jps.20206] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this work was to investigate the contribution of the paracellular route to the pH-dependent permeability to cationic drugs in three models expressing different drug permeabilities: hexadecane membranes (HDMs), Caco-2, and 2/4/A1 cell monolayers. The high- and low-permeability drugs alfentanil and cimetidine were used as model drugs. The paracellular permeability was calculated: 1. from the assumption that the ionized form (P(mi)) permeates a cell monolayer only by the paracellular route, and 2. on basis of the pore-restricted diffusion. For both drugs, sigmoidal relationships between membrane permeability and pH were observed in all models. The P(mi) was in excellent agreement with the paracellular permeability of cimetidine in the two cell models, whereas no significant P(mi) of the drugs could be observed in HDM. The results showed that the paracellular route has a significant role in the permeability of small basic hydrophilic drugs, such as cimetidine in leaky, small intestinal-like epithelia such as 2/4/A1. By contrast, in tighter epithelia such as Caco-2 and in artificial membranes such as HDM, the permeability of the ionized forms of the drugs and the paracellular permeability are lower or insignificant, respectively. These findings will have implications in the experimental design and data interpretation of pH-dependent drug transport experiments in cell culture models as well as in artificial membrane models such as HDM and parallel artificial membrane permeability assay (PAMPA).
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Affiliation(s)
- Naoki Nagahara
- Department of Pharmacy, Uppsala University, PO Box 580, SE-75123 Uppsala, Sweden
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11
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Hosoya KI, Tomi M, Takayama M, Komokata Y, Nakai D, Tokui T, Nishimura K, Ueda M, Obinata M, Hori S, Ohtsuki S, Amidon GL, Terasaki T. Transporter mRNA Expression in a Conditionally Immortalized Rat Small Intestine Epithelial Cell Line (TR-SIE). Drug Metab Pharmacokinet 2004; 19:264-9. [PMID: 15499194 DOI: 10.2133/dmpk.19.264] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Small intestine epithelial cell lines (TR-SIE), which are established from the small intestine of transgenic rats harboring temperature-sensitive simian virus 40 large T-antigen gene (tsA58 Tg rat), were used to characterize the mRNA expression of small intestine transporters. TR-SIE cells had a polygonal morphology and expressed cytokeratin protein and villin mRNA. Although the large T-antigen was strongly expressed at 33 degrees C, this was reduced at 37 and 39 degrees C. Concomitantly, the cell growth was arrested at 37 and 39 degrees C compared with that at 33 degrees C, suggesting that TR-SIE cells are conditionally immortalized cell lines. RT-PCR analysis revealed that TR-SIE cells expressed ABCB1 (mdr1a and mdr1b), ABCB4 (mdr2), ABCC2 (mrp2), ABCC6 (mrp6), ABCG1, ABCG2 (bcrp/mxr), Slc21a7 (Oatp3), Slc15a1 (PepT1), and Slc16a1 (Mct1). Conditionally immortalized rat small intestine epithelial cell lines were established from tsA58 Tg rats and expressed the mRNA of intestinal transporters.
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Affiliation(s)
- Ken-ichi Hosoya
- Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Sugitani, Japan.
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12
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Tavelin S, Taipalensuu J, Söderberg L, Morrison R, Chong S, Artursson P. Prediction of the oral absorption of low-permeability drugs using small intestine-like 2/4/A1 cell monolayers. Pharm Res 2003; 20:397-405. [PMID: 12669959 DOI: 10.1023/a:1022699920043] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE To characterize the paracellular route of 2/4/A1 monolayers and to compare the permeabilities of incompletely absorbed oral drugs in 2/4/A1 with those in Caco-2 monolayers. METHODS The cells were cultivated on permeable supports. The 2/4/ A1 expression of genes associated with tight junctions was compared with that in the small intestine using RT-PCR. The aqueous pore radii were determined using paracellular marker molecules. The permeabilities of a series of incompletely absorbed drugs (defined as having a fraction absorbed 0 to 80%) after oral administration to humans were studied. RESULTS Occludin and claudin 1 and 3 were expressed in 2/4/A1. The pore radius of 2/4/A1 was 9.0 +/- 0.2 A. which is similar to that in the human small intestine, although the pore radius was smaller (3.7 +/- 0.1 A) in Caco-2. The relationship between permeability and fraction absorbed of 13 drugs was stronger in 2/4/A1 than in Caco-2. The relationships were used to predict the intestinal absorption of another seven drugs. The prediction was more accurate in 2/4/A1 (RMSE = 15.6%) than in Caco-2 (RMSE = 21.1%). Further, Spearman's rank coefficient between FA and permeability was higher in 2/4/A1. CONCLUSION The improved 2/4/A1 cell culture model has a more in vivo-like permeability and predicted the oral absorption of incompletely absorbed drugs better than Caco-2 cells.
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Affiliation(s)
- Staffan Tavelin
- Department of Pharmacy, Uppsala University, SE-751 23 Uppsala, Sweden
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13
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Tavelin S, Taipalensuu J, Hallböök F, Vellonen KS, Moore V, Artursson P. An improved cell culture model based on 2/4/A1 cell monolayers for studies of intestinal drug transport: characterization of transport routes. Pharm Res 2003; 20:373-81. [PMID: 12669956 DOI: 10.1023/a:1022643802296] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PURPOSE To improve the viability of the 2/4/A1 cell culture model and to investigate different routes of drug transport in this cell line. METHODS Two approaches were taken to decrease apoptosis. First, rat intestinal 2/4/A1 cells were transfected to overexpress the antiapoptotic protein Bcl-2. Second. normal 2/4/A1 cells were cultivated under conditions that stimulate differentiation and limit apoptosis. The monolayer integrity was investigated by transepithelial electrical resistance, permeability, and microscopy. The expression of drug transporters was investigated by RT-PCR, and transport function was assessed using specific markers. RESULTS Normal 2/4/A1 cells died by apoptosis at 39 degrees C. Bcl-2-expressing 2/4/A1 cells were viable but adopted a morphology of less-differentiated epithelial cells. Optimization of the culture conditions for 2/4/A1 cells inhibited cell death. The integrity was comparable to that of the human jejunum (50 omega x cm2), making this approach preferable to Bcl-2 overexpression. Transcriptional analysis showed that some (e.g., MDRI). but not all (e.g., PepT1), transporters were found in 2/4/A1 cells. Studies using substrates for PepT1, P-gp. MRP2, and BCRP showed that none of the transporters were functional in 2/4/A1. CONCLUSIONS The improved culture procedure will facilitate the use of 2/4/A1 cells. 2/4/A1 lack several transporters, which makes them a promising alternative to Caco-2 cells and artificial membranes in studies of passive drug transport.
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Affiliation(s)
- Staffan Tavelin
- Department of Pharmacy, Uppsala University, SE-751 23 Uppsala, Sweden
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14
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Clatworthy JP, Subramanian V. Stem cells and the regulation of proliferation, differentiation and patterning in the intestinal epithelium: emerging insights from gene expression patterns, transgenic and gene ablation studies. Mech Dev 2001; 101:3-9. [PMID: 11231054 DOI: 10.1016/s0925-4773(00)00557-8] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Tissues that undergo self-renewal such as the skin, the haematopoeitic system and the intestine are all maintained and renewed by a small group of multipotent stem cells. The stem cells of the intestinal epithelium are located in the crypts and give rise to its four main lineages located mainly in the finger like projections- the villi. An increasing number of genes are now being identified as either being necessary for or involved in the maintenance of intestinal stem cells and regulating differentiation along the crypt-villus axis. These developmental regulatory genes include among others, Tcf-4, Cdx-1 Fkh6, HFH11 and Nkx2-3. Other genes such as the integrins, and Indian hedgehog (Ihh) also affect function of the progenitor cells of the intestinal epithelium. This mini-review will focus on the more recent data on expression patterns of genes in the intestinal epithelium and the direct or indirect effects of their ablation on proliferation and differentiation.
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Affiliation(s)
- J P Clatworthy
- Department of Biology and Biochemistry, South Building, University of Bath, BA2 7AY, Bath, UK
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15
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Artursson P, Palm K, Luthman K. Caco-2 monolayers in experimental and theoretical predictions of drug transport. Adv Drug Deliv Rev 2001; 46:27-43. [PMID: 11259831 DOI: 10.1016/s0169-409x(00)00128-9] [Citation(s) in RCA: 950] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review examines the use of Caco-2 monolayers in the prediction of intestinal drug absorption. First, the different routes of drug transport in Caco-2 monolayers are compared with those seen in vivo. Second, the prediction of drug absorption in vivo from transport experiments in cell monolayers is discussed for different classes of drugs. Finally, the use of Caco-2 monolayers as a reference model in physico-chemical and theoretical predictions of drug absorption is discussed. We conclude that Caco-2 monolayers can be used to identify drugs with potential absorption problems, and possibly also to select drugs with optimal passive absorption characteristics from series of pharmacologically active molecules generated in drug discovery programs.
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Affiliation(s)
- P Artursson
- Department of Pharmaceutics, Uppsala Biomedical Centre, Uppsala University, Box 580, S-751 23, Uppsala, Sweden
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16
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Thomas EJ, Gabriel SE, Makhlina M, Hardy SP, Lethem MI. Expression of nucleotide-regulated Cl(-) currents in CF and normal mouse tracheal epithelial cell lines. Am J Physiol Cell Physiol 2000; 279:C1578-86. [PMID: 11029305 DOI: 10.1152/ajpcell.2000.279.5.c1578] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The dominant route for Cl(-) secretion in mouse tracheal epithelium is via Cl(-) channels different from the cystic fibrosis (CF) transmembrane conductance regulator (CFTR), the channel that is defective in CF. It has been proposed that the use of purinergic agonists to activate these alternative channels in human airways may be beneficial in CF. In the present study, two conditionally immortal epithelial cell lines were established from the tracheae of mice possessing the tsA58 T antigen gene, one of which [MTE18-(-/-)] was homozygous for a knockout of CFTR and the other [MTE7b-(+/-)] heterozygous for CFTR expression. In Ussing chamber studies, amiloride (10(-4) M) and a cocktail of cAMP-activating agents (forskolin, IBMX, and dibutyryl cAMP) resulted in small changes in the short-circuit current (I(sc)) and resistance of both cell lines, with larger increases in I(sc) being elicited by ionomycin (10(-6) M). Both cell lines expressed P(2)Y(2) receptors and responded to the purinergic agonists ATP, UTP, and 5'-adenylylimidodiphosphate (10(-4) M) with an increase in I(sc). This response could be inhibited by DIDS and was abolished in the presence of Cl(-)-free Ringer solution. Reducing the mucosal Cl(-) concentration increased the response to UTP of both cell lines, with a significantly greater increase in MTE18-(-/-) cells. Pretreatment of these cells with thapsigargin caused a direct increase in I(sc) and inhibited the response to UTP. These data suggest that both cell lines express purinergic-regulated Cl(-) currents and may prove valuable tools in studying the properties of this pathway.
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Affiliation(s)
- E J Thomas
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Brighton BN2 4GJ, United Kingdom
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17
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Quaroni A, Tian JQ, Seth P, Ap Rhys C. p27(Kip1) is an inducer of intestinal epithelial cell differentiation. Am J Physiol Cell Physiol 2000; 279:C1045-57. [PMID: 11003585 DOI: 10.1152/ajpcell.2000.279.4.c1045] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Constant renewal of the intestinal epithelium is a highly coordinated process that has been subject to intense investigation, but its regulatory mechanisms are still essentially unknown. In this study, we have demonstrated that forced expression of the cyclin-dependent kinase inhibitors (CKIs) p27(Kip1) and p21(Cip1/WAF1) in human intestinal epithelial cells led to expression of differentiation markers at both the mRNA and protein levels. Cell differentiation was temporally dissociated from inhibition of retinoblastoma protein phosphorylation and growth arrest, already established 1 day after infection with recombinant adenoviruses. p27(Kip1) proved significantly more efficient than p21(Cip1/WAF1) in induction of cell differentiation. In contrast, forced expression of p16(INK4a) resulted in growth arrest without induction of differentiation markers. These results implicate both p27(Kip1) and p21(Cip1/WAF1) in the differentiation-timing process, but p21(Cip1/WAF1) may act indirectly by increasing p27(Kip1) levels. These results also suggest that induction of intestinal epithelial cell differentiation by CKIs is not related to their effects on the cell cycle and may involve interactions with cellular components other than cyclins and cyclin-dependent kinases.
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Affiliation(s)
- A Quaroni
- Section of Physiology, Cornell University, Ithaca, New York 14853, USA.
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18
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Pageot LP, Perreault N, Basora N, Francoeur C, Magny P, Beaulieu JF. Human cell models to study small intestinal functions: recapitulation of the crypt-villus axis. Microsc Res Tech 2000; 49:394-406. [PMID: 10820523 DOI: 10.1002/(sici)1097-0029(20000515)49:4<394::aid-jemt8>3.0.co;2-k] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The intestinal epithelium is continuously and rapidly renewed by a process involving cell generation, migration, and differentiation, from the stem cell population located at the bottom of the crypt to the extrusion of the terminally differentiated cells at the tip of the villus. Because of the lack of normal human intestinal cell models, most of our knowledge about the regulation of human intestinal cell functions has been derived from studies conducted on cell cultures generated from experimental animals and human colon cancers. However, important advances have been achieved over recent years in the generation of normal human intestinal cell models. These models include (a) intestinal cell lines with typical crypt cell proliferative noncommitted characteristics, (b) conditionally immortalized intestinal cell lines that can be induced to differentiate, and (c) primary cultures of differentiated villuslike cells that can be maintained in culture for up to 10 days. Each of these models should help in the investigation of the specific aspects of human intestinal function and regulation. Furthermore, taken together, these models provide an integrated system that allows an in vitro recapitulation of the entire crypt-villus axis of the normal human small intestine.
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Affiliation(s)
- L P Pageot
- MRC Group in Functional Development and Physiopathology of the Digestive Tract, Département d'anatomie et de biologie cellulaire, Faculté de médecine, Université de Sherbrooke, Sherbrooke, Québec, Canada J1H 5N4
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19
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Abstract
Lead compounds generated in high throughput drug discovery programmes often have unfavorable biopharmaceutical properties, resulting in a low success rate of such drug candidates in clinical development. Drug companies and researchers would thus like to have methods of predicting biopharmaceutical properties accurately. The intestinal permeability to a lead compound is one such property which is particularly important. Therefore, access to methods to accurately predict biopharmaceutical properties, such as the intestinal permeability of a large series of compounds, is of particular importance. This review deals with new theoretical methods used to predict intestinal drug permeability. There are several possible transport routes across the intestine, but theoretical methods generally deal with only one of them, the passive transcellular route. Therefore, this review will also discuss the relative importance of passive and active drug transport and efflux routes using recent data generated in cell cultures, animal models and human subjects.
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Affiliation(s)
- P Stenberg
- Department of Pharmaceutics, Uppsala Biomedical Centre, Uppsala University, P.O. Box 580, SE-751 23, Uppsala, Sweden
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20
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Quaroni A, Tian JQ, Göke M, Podolsky DK. Glucocorticoids have pleiotropic effects on small intestinal crypt cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:G1027-40. [PMID: 10564109 DOI: 10.1152/ajpgi.1999.277.5.g1027] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Glucocorticoids have long been known to accelerate maturation of the intestinal tract, but the molecular mechanisms that account for their physiological function in the epithelium remain poorly characterized. Using rat intestinal epithelial cell lines (IEC-6, IEC-17, and IEC-18) as models, we have characterized glucocorticoid receptors in crypt cells and documented striking morphological, ultrastructural, and functional alterations induced by these hormones in intestinal cells. They include arrest of growth, formation of tight junctions, appearance of long, slender microvilli, reorganization of the endoplasmic reticulum and trans-Golgi network, and downregulation of the cell cycle regulatory proteins cyclin-dependent kinase 6 and p27(Kip1). These effects are consistent with the activation or modulation of multiple genes important in the physiological function of absorptive villous cells but are probably not directly involved in the induction of cell differentiation.
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Affiliation(s)
- A Quaroni
- Section of Physiology, Cornell University, Ithaca, New York 14853, USA.
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21
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Tian JQ, Quaroni A. Involvement of p21(WAF1/Cip1) and p27(Kip1) in intestinal epithelial cell differentiation. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:C1245-58. [PMID: 10362586 DOI: 10.1152/ajpcell.1999.276.6.c1245] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Using the conditionally immortalized human cell line tsFHI, we have investigated the role of cyclin-dependent kinase inhibitors (CKIs) in intestinal epithelial cell differentiation. Expression of cyclins, cyclin-dependent kinases (Cdk), and CKIs was examined under conditions promoting growth, growth arrest, or expression of differentiated traits. Formation of complexes among cell cycle regulatory proteins and their kinase activities were also investigated. The tsFHI cells express three CKIs: p16, p21, and p27. With differentiation, p21 and p27 were strongly induced, but with different kinetics: the p21 increase was rapid but transient and the p27 increase was delayed but sustained. Our results suggest that the function of p16 is primarily to inhibit cyclin D-associated kinases, making tsFHI cells dependent on cyclin E-Cdk2 for pRb phosphorylation and G1/S progression. Furthermore, they indicate that p21 is the main CKI involved in irreversible growth arrest during the early stages of cell differentiation in association with D-type cyclins, cyclin E, and Cdk2, whereas p27 may induce or stabilize expression of differentiated traits acting independently of cyclin-Cdk function.
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Affiliation(s)
- J Q Tian
- Section of Physiology, Cornell University, Ithaca, New York 14853, USA
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22
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Evers BM. Intestinal cell differentiation: cellular mechanisms and the search for the perfect model focus on "involvement of p21(WAF1/Cip1) and p27(Kip1) in intestinal epithelial cell differentiation". THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:C1243-4. [PMID: 10362585 DOI: 10.1152/ajpcell.1999.276.6.c1243] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- B M Evers
- Department of Surgery, The University of Texas Medical Branch, Galveston, Texas 77555-0533, USA.
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23
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Gratchev A, Böhm C, Riede E, Foss HD, Hummel M, Mann B, Backert S, Buhr HJ, Stein H, Riecken EO, Hanski C. Regulation of mucin MUC2 gene expression during colon carcinogenesis. Ann N Y Acad Sci 1998; 859:180-3. [PMID: 9928381 DOI: 10.1111/j.1749-6632.1998.tb11122.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- A Gratchev
- Medizinische Klinik I, Universitätsklinikum Benjamin Franklin der Freien Universität Berlin, Germany
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Abstract
Ongoing and future approaches to the cellular and molecular actions of insulin-like growth factor I (IGF-I) and growth hormone (GH) in intestinal adaptation are reviewed. This is highly relevant to understanding the benefits and risks associated with increasing use of GH and IGF-I in patients with short bowel syndrome or other bowel diseases. As other growth factors share some of the properties of IGF-I including local expression in bowel, activation of signaling pathways common to other growth factors or cytokines, and modulation of action by growth factor-binding proteins or secreted receptor isoforms. The general issues and approaches outlined for IGF-I should, therefore, serve as a model for studies aimed at understanding the cellular and molecular mechanisms of action of other growth factors that are implicated in intestinal adaptation.
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Affiliation(s)
- P K Lund
- Department of Physiology, University of North Carolina, Chapel Hill 27514, USA.
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Milovic V, Ocklind G, Artursson P. Conditionally immortalized intestinal epithelial cells. A new model for studying intestinal epithelial cell turnover. Ann N Y Acad Sci 1998; 859:201-3. [PMID: 9928387 DOI: 10.1111/j.1749-6632.1998.tb11128.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- V Milovic
- Department of Pharmaceutics, Uppsala University, Sweden
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Djelloul S, Forgue-Lafitte ME, Hermelin B, Mareel M, Bruyneel E, Baldi A, Giordano A, Chastre E, Gespach C. Enterocyte differentiation is compatible with SV40 large T expression and loss of p53 function in human colonic Caco-2 cells. Status of the pRb1 and pRb2 tumor suppressor gene products. FEBS Lett 1997; 406:234-42. [PMID: 9136893 DOI: 10.1016/s0014-5793(97)00208-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Transfer of the SV40 large-T (LT) oncogene into isolated human and murine intestinal epithelial cells induced alterations of the ultrastructural organization and polarization of the resulting immortalized cell lines. We now demonstrate that the functional expression of the SV40 LT antigen in Caco-2 cells did not alter phenotypic markers of differentiation, including expression of villin, sucrase-isomaltase, brush border and dome formation. As compared to parental cells, the transfected Caco-2 LT9 cells exhibited similar growth curves and no invasive properties in vitro. The major oncogenic function of the SV40 LT antigen in transfected Caco-2 cells is associated with reduced latency times necessary for the manifestation of tumors in athymic nude mice. The Caco-2 cell line contained deleted and mutant p53 alleles (stop codon in position 204) and has no detectable truncated p53 protein by Western blot. Molecular complexes between the SV40 LT antigen and the retinoblastoma-related proteins pRb1 and Rb2 were clearly identified at the different phases of the growth curve. When compared to normal human colonic crypts, Caco-2 cell differentiation is related to partial redistribution of pRb1 into hypophosphorylated, antiproliferative forms. The pRb2 protein is found elevated in a subset of human colorectal tumors and their corresponding liver metastases. We conclude that: (1) Caco-2 cells exert a dominant control against the oncogenic functions of the LT antigen; (2) loss of p53 function is not restrictive for the establishment of polarity and differentiation of the enterocyte lineage; (3) the levels and phosphorylation status of the Rb1 and Rb2 proteins may play important roles in the proliferation and differentiation of normal and neoplastic human colonic mucosa.
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Affiliation(s)
- S Djelloul
- INSERM U55 Equipe Cancerogénèse et Différenciation de l'Epithélium Gastro-Intestinal, Hôpital Saint-Antoine, Paris, France
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27
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28
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Corpe CP, Basaleh MM, Affleck J, Gould G, Jess TJ, Kellett GL. The regulation of GLUT5 and GLUT2 activity in the adaptation of intestinal brush-border fructose transport in diabetes. Pflugers Arch 1996; 432:192-201. [PMID: 8662294 DOI: 10.1007/s004240050124] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The adaptation of d-fructose transport in rat jejunum to experimental diabetes has been studied. In vivo and in vitro perfusions of intact jejunum with d-fructose revealed the appearance of a phloretin-sensitive transporter in the brush-border membrane of streptozotocin-diabetic rats which was not detectable in normal rats. The nature of the transporters involved was investigated by Western blotting and by d-fructose transport studies using highly purified brush-border and basolateral membrane vesicles. GLUT5, the major transporter in the brush-border membrane of normal rats, was not inhibited by d-glucose or phloretin. In contrast, GLUT2, the major transporter in the basolateral membrane of normal rats, was strongly inhibited by both D-glucose and phloretin. In brush-border membrane vesicles from diabetic rats, GLUT5 levels were significantly enhanced; moreover the presence of GLUT2 was readily detectable and increased markedly as diabetes progressed. The differences in stereospecificity between GLUT2 and GLUT5 were used to show that both transporters contributed to the overall enhancement of d-fructose transport measured in brush-border membrane vesicles and in vitro isolated loops from diabetic rats. However, overall d-fructose uptake in vivo was diminished. The underlying mechanisms and functional consequences are discussed.
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Affiliation(s)
- C P Corpe
- Department of Biology, University of York, PO Box 373, York YO1 5YW, UK
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30
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Zavizion B, van Duffelen M, Schaeffer W, Politis I. Establishment and characterization of a bovine mammary myoepithelial cell line. In Vitro Cell Dev Biol Anim 1996; 32:149-58. [PMID: 8925137 DOI: 10.1007/bf02723680] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The thermolabile large T-antigen, encoded by the simian virus 40 early region mutant tsA58, was used to establish clonal cell lines (BMM-UV) from primary bovine myoepithelial cells. The BMM-UV cells have undergone more than 300 population doublings without any signs of senescence, and they contain the intranuclear large T antigen. At low confluency, they grow in a spindlelike manner and develop very long projections that most likely allow for communication of cells at a distance from each other. Establishment results in a decrease in the number of cells that contract in response to oxytocin compared with the parental nontransfected cells (20% versus 45%). Oxytocin responsiveness of BMM-UV cells increases when the cells are cultured in a medium supplemented with staphylococcal proteases. Proliferation of BMM-UV cells increases when they are cultured in the presence of epidermal growth factor (10 ng/ml) or insulinlike growth factor I (50 ng/ml). The BMM-UV cells may become a useful model to study growth properties, cell-to-cell communication, and the function of bovine mammary myoepithelial cells.
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Affiliation(s)
- B Zavizion
- Department of Animal and Food Sciences, University of Vermont, Burlington 05405, USA
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31
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Zavizion B, van Duffelen M, Schaeffer W, Politis I. Establishment and characterization of a bovine mammary epithelial cell line with unique properties. In Vitro Cell Dev Biol Anim 1996; 32:138-48. [PMID: 8925136 DOI: 10.1007/bf02723679] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Clonal cell lines (BME-UV) were established from primary epithelial cells by stable transfection with a plasmid, carrying the sequence of the simian virus 40 early region mutant tsA58, encoding the thermolabile large T antigen. The BME-UV cells have undergone more than 300 population doublings and produce intranuclear large T antigen. At low confluency, growing islands of cells are apparent exhibiting the characteristic cobblestone morphology of epithelial cells. The BME-UV cells expressed functional markers such as microvilli and desmosomes and biochemical markers of mammary epithelial cells such as a repertoire of cytokeratins. The BME-UV cells are capable of synthesizing low levels of alpha-lactalbumin and alpha s1-casein (50 ng/ml of medium/24 h). One of the cell lines, BME-UV1 showed enhanced proliferation in the presence of epidermal growth factor (EGF) and insulinlike growth factor I (IGF-I). The BME-UV1 cell line is the only known bovine mammary epithelial cell line responsive to EGF. The BME-UV cells grown on collagen at low confluency are capable of developing very long projections that most likely allow for communication between cells at a distance from each other. The BME-UV cells may become a valid model system to examine bovine mammary epithelial proliferation and differentiation and cell-to-cell communication.
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Affiliation(s)
- B Zavizion
- Department of Animal and Food Sciences, University of Vermont, Burlington 05405, USA
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