201
|
Randall K, Henderson N, Reens J, Eckersley S, Nyström AC, South MC, Balendran CA, Böttcher G, Hughes G, Price SA. Claudin-2 Expression Levels in Ulcerative Colitis: Development and Validation of an In-Situ Hybridisation Assay for Therapeutic Studies. PLoS One 2016; 11:e0162076. [PMID: 27598247 PMCID: PMC5012586 DOI: 10.1371/journal.pone.0162076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 08/17/2016] [Indexed: 12/17/2022] Open
Abstract
Ulcerative colitis is a chronic inflammatory disease affecting the colon and is characterized by epithelial damage and barrier dysfunction. Upregulation of the tight junction protein claudin-2 by cytokines is hypothesized to contribute to the dysregulation of the epithelial barrier. New therapeutic agents which block the action of cytokines are being investigated in patients with ulcerative colitis. In order to understand the potential of these therapies, it is important to have reliable assays that can assess downstream endpoints that reflect drug mechanism of action. The aim of the current study was therefore to establish & validate an assay to reproducibly assess the expression and distribution of claudin-2 in human colon biopsy samples. Initially, the potential to measure claudin-2 protein by immunohistochemistry (IHC) was investigated. To identify suitable reagents to develop an IHC assay, pre-established criteria were used to screen five commercial antibodies by Western blotting, immunofluorescence and immunohistochemistry on claudin-2 positive and negative cells and healthy and ulcerative colitis colon tissue. Despite some of these antibodies specifically detecting claudin-2 using some of these techniques, none of the antibodies showed the expected specific staining pattern in formalin fixed human colon samples. As an alternative method to detect claudin-2 expression and distribution in formalin fixed biopsy sections, an in situ hybridization assay was developed. This assay underwent a novel tiered approach of validation to establish that it was fit-for-purpose, and suitable for clinical deployment. In addition, to understand the possible relationship of claudin-2 in the context of disease severity, expression was compared to the Geboes score. Overall, the microscopical Geboes score correlated with the claudin-2 biomarker score for samples that retained crypt morphology; samples with the highest Geboes score were not specifically distinguished, probably due to crypt destruction. In summary, we have applied a strategy for identifying target-specific antibodies in formalin fixed biopsy samples and highlighted that (published) antibodies may not correctly identify the intended antigen in tissues fixed using this method. Furthermore, we have developed and, for the first time, validated an in situ hybridization assay for detection of claudin-2 mRNA, suitable for use as a supportative method in clinical trials. Using our validated assay, we have demonstrated that increased claudin-2 expression correlates with the severity of ulcerative colitis, where crypt destruction is not seen.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Glen Hughes
- AstraZeneca R&D, Alderley Park, United Kingdom
| | | |
Collapse
|
202
|
Ronaghan NJ, Shang J, Iablokov V, Zaheer R, Colarusso P, Dion S, Désilets A, Leduc R, Turner JR, MacNaughton WK. The serine protease-mediated increase in intestinal epithelial barrier function is dependent on occludin and requires an intact tight junction. Am J Physiol Gastrointest Liver Physiol 2016; 311:G466-79. [PMID: 27492333 PMCID: PMC5076006 DOI: 10.1152/ajpgi.00441.2015] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 07/28/2016] [Indexed: 01/31/2023]
Abstract
Barrier dysfunction is a characteristic of the inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis. Understanding how the tight junction is modified to maintain barrier function may provide avenues for treatment of IBD. We have previously shown that the apical addition of serine proteases to intestinal epithelial cell lines causes a rapid and sustained increase in transepithelial electrical resistance (TER), but the mechanisms are unknown. We hypothesized that serine proteases increase barrier function through trafficking and insertion of tight junction proteins into the membrane, and this could enhance recovery of a disrupted monolayer after calcium switch or cytokine treatment. In the canine epithelial cell line, SCBN, we showed that matriptase, an endogenous serine protease, could potently increase TER. Using detergent solubility-based cell fractionation, we found that neither trypsin nor matriptase treatment changed levels of tight junction proteins at the membrane. In a fast calcium switch assay, serine proteases did not enhance the rate of recovery of the junction. In addition, serine proteases could not reverse barrier disruption induced by IFNγ and TNFα. We knocked down occludin in our cells using siRNA and found this prevented the serine protease-induced increase in TER. Using fluorescence recovery after photobleaching (FRAP), we found serine proteases induce a greater mobile fraction of occludin in the membrane. These data suggest that a functional tight junction is needed for serine proteases to have an effect on TER, and that occludin is a crucial tight junction protein in this mechanism.
Collapse
Affiliation(s)
- Natalie J. Ronaghan
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| | - Judie Shang
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| | - Vadim Iablokov
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| | - Raza Zaheer
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| | - Pina Colarusso
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| | - Sébastien Dion
- 2Département de Pharmacologie-Physiologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada; and
| | - Antoine Désilets
- 2Département de Pharmacologie-Physiologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada; and
| | - Richard Leduc
- 2Département de Pharmacologie-Physiologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada; and
| | - Jerrold R. Turner
- 3Departments of Pathology and Medicine (GI), Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Wallace K. MacNaughton
- 1Department of Physiology and Pharmacology and Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
| |
Collapse
|
203
|
Bagwe S, Tharappel LJP, Kaur G, Buttar HS. Bovine colostrum: an emerging nutraceutical. JOURNAL OF COMPLEMENTARY & INTEGRATIVE MEDICINE 2016; 12:175-85. [PMID: 25781716 DOI: 10.1515/jcim-2014-0039] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 01/29/2015] [Indexed: 02/02/2023]
Abstract
Nutraceutical, a term combining the words "nutrition" and "pharmaceuticals", is a food or food product that provides health benefits as an adjuvant or alternative therapy, including the treatment and prevention of infectious diseases in children and adults. There is emerging evidence that bovine colostrum (BC) may be one of the promising nutraceuticals which can prevent or mitigate various diseases in newborns and adults. Immunity-related disorders are one of the leading causes of mortality in the world. BC is rich in immunity, growth and antimicrobial factors, which promote tissue growth and the maturation of digestive tract and immune function in neonatal animals and humans. The immunoglobulins and lactoferrin present in colostrum are known to build natural immunity in newborns which helps to reduce the mortality rate in this population. Also, the side-effect profile of colostrum proteins and possible lactose intolerance is relatively less in comparison with milk. In general, BC is considered safe and well tolerated. Since colostrum has several important nutritional constituents, well-designed, double-blind, placebo-controlled studies with colostrum products should be conducted to widen its therapeutic use. The objectives of this review are to create awareness about the nutraceutical properties of colostrum and to discuss the various ongoing alternative treatments of colostrum and its active ingredients as well as to address colostrum's future nutraceutical and therapeutic implications in humans.
Collapse
|
204
|
Meir M, Flemming S, Burkard N, Wagner J, Germer CT, Schlegel N. The glial cell-line derived neurotrophic factor: a novel regulator of intestinal barrier function in health and disease. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1118-23. [PMID: 27151942 DOI: 10.1152/ajpgi.00125.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 04/28/2016] [Indexed: 01/31/2023]
Abstract
Regulation of the intestinal epithelial barrier is a differentiated process, which is profoundly deranged in inflammatory bowel diseases. Recent data provide evidence that the glial cell line-derived neurotrophic factor (GDNF) is critically involved in intestinal epithelial wound healing and barrier maturation and exerts antiapoptotic effects under certain conditions. Furthermore, not only the enteric nervous system, but also enterocytes synthesize GDNF in significant amounts, which points to a potential para- or autocrine signaling loop between enterocytes. Apart from direct effects of GDNF on enterocytes, an immunomodulatory role of this protein has been previously assumed because of a significant reduction of inflammation in a model of chronic inflammatory bowel disease after application of GDNF. In this review we summarize the current knowledge of GDNF on intestinal epithelial barrier regulation and discuss the novel role for GDNF as a regulator of intestinal barrier functions in health and disease.
Collapse
Affiliation(s)
- Michael Meir
- Department of Surgery I; University of Wuerzburg, Wuerzburg, Germany
| | - Sven Flemming
- Department of Surgery I; University of Wuerzburg, Wuerzburg, Germany
| | - Natalie Burkard
- Department of Surgery I; University of Wuerzburg, Wuerzburg, Germany
| | - Johanna Wagner
- Department of Surgery I; University of Wuerzburg, Wuerzburg, Germany
| | | | - Nicolas Schlegel
- Department of Surgery I; University of Wuerzburg, Wuerzburg, Germany
| |
Collapse
|
205
|
Landy J, Ronde E, English N, Clark SK, Hart AL, Knight SC, Ciclitira PJ, Al-Hassi HO. Tight junctions in inflammatory bowel diseases and inflammatory bowel disease associated colorectal cancer. World J Gastroenterol 2016; 22:3117-3126. [PMID: 27003989 PMCID: PMC4789987 DOI: 10.3748/wjg.v22.i11.3117] [Citation(s) in RCA: 325] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 09/19/2015] [Accepted: 12/21/2015] [Indexed: 02/06/2023] Open
Abstract
Inflammatory bowel diseases are characterised by inflammation that compromises the integrity of the epithelial barrier. The intestinal epithelium is not only a static barrier but has evolved complex mechanisms to control and regulate bacterial interactions with the mucosal surface. Apical tight junction proteins are critical in the maintenance of epithelial barrier function and control of paracellular permeability. The characterisation of alterations in tight junction proteins as key players in epithelial barrier function in inflammatory bowel diseases is rapidly enhancing our understanding of critical mechanisms in disease pathogenesis as well as novel therapeutic opportunities. Here we give an overview of recent literature focusing on the role of tight junction proteins, in particular claudins, in inflammatory bowel diseases and inflammatory bowel disease associated colorectal cancer.
Collapse
|
206
|
Baker OJ. Current trends in salivary gland tight junctions. Tissue Barriers 2016; 4:e1162348. [PMID: 27583188 DOI: 10.1080/21688370.2016.1162348] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 02/28/2016] [Accepted: 03/01/2016] [Indexed: 12/21/2022] Open
Abstract
Tight junctions form a continuous intercellular barrier between epithelial cells that is required to separate tissue spaces and regulate selective movement of solutes across the epithelium. They are composed of strands containing integral membrane proteins (e.g., claudins, occludin and tricellulin, junctional adhesion molecules and the coxsackie adenovirus receptor). These proteins are anchored to the cytoskeleton via scaffolding proteins such as ZO-1 and ZO-2. In salivary glands, tight junctions are involved in polarized saliva secretion and barrier maintenance between the extracellular environment and the glandular lumen. This review seeks to provide an overview of what is currently known, as well as the major questions and future research directions, regarding tight junction expression, organization and function within salivary glands.
Collapse
Affiliation(s)
- Olga J Baker
- School of Dentistry, University of Utah , Salt Lake City, UT, USA
| |
Collapse
|
207
|
Huerta M, Rivnay J, Ramuz M, Hama A, Owens RM. Early Detection of NephrotoxicityIn VitroUsing a Transparent Conducting Polymer Device. ACTA ACUST UNITED AC 2016. [DOI: 10.1089/aivt.2015.0028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Miriam Huerta
- Department of Bioelectronics, École Nationale Supérieure des Mines, Gardanne, France
| | - Jonathan Rivnay
- Department of Bioelectronics, École Nationale Supérieure des Mines, Gardanne, France
| | - Marc Ramuz
- Department of Bioelectronics, École Nationale Supérieure des Mines, Gardanne, France
| | - Adel Hama
- Department of Bioelectronics, École Nationale Supérieure des Mines, Gardanne, France
| | - Roisin M. Owens
- Department of Bioelectronics, École Nationale Supérieure des Mines, Gardanne, France
| |
Collapse
|
208
|
Steinemann A, Galm I, Chip S, Nitsch C, Maly IP. Claudin-1, -2 and -3 Are Selectively Expressed in the Epithelia of the Choroid Plexus of the Mouse from Early Development and into Adulthood While Claudin-5 is Restricted to Endothelial Cells. Front Neuroanat 2016; 10:16. [PMID: 26941614 PMCID: PMC4761916 DOI: 10.3389/fnana.2016.00016] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 02/05/2016] [Indexed: 12/22/2022] Open
Abstract
A primary function of epithelial and endothelial monolayers is the formation of barriers that separate tissues into functional compartments. Tight junctions (TJs) seal the intercellular space between the single cells of a monolayer. TJs thus contribute importantly to the homeostasis of the cerebrospinal fluid as they help in maintaining the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (CSF). The composition of TJs differs by its localization as well as the stage of development according to its respective function. Claudin-3 is typically present in the epithelia and has been claimed to be a constituent of the BBB. It is, however, notoriously difficult to demonstrate its expression in endothelial cells of the brain vasculature at the morphological level by means of immunohistochemical techniques. Using an improved fixation strategy (4% paraformaldehyde at pH 11, in the presence of EDTA) and the sensitive alkaline phosphatase as a detection system, we show that claudin-3 is present in mouse epithelia from embryonic day 14 onwards. In brain, it is restricted to the anlage of choroid plexus in the ventricles, together with claudin-1 and -2. In adult mice, it is clearly delineating the epithelium of the choroid plexus in the lateral and fourth ventricles. In contrast, in cerebral blood vessels claudin-3 as well as claudin-1 and -2 are absent in cerebral blood vessels during all developmental stages up to adulthood. Rather, the BBB is characterized by the presence of claudin-5, ZO-1 and occludin. Thus, in mice claudin-3 is an important constituent of TJ in the embryonic and in the adult choroid plexus.
Collapse
Affiliation(s)
- Alexandra Steinemann
- Department of Biomedicine, Section of Functional Neuroanatomy, University of Basel Basel, Switzerland
| | - Isabel Galm
- Department of Biomedicine, Section of Functional Neuroanatomy, University of Basel Basel, Switzerland
| | - Sophorn Chip
- Department of Biomedicine, Section of Functional Neuroanatomy, University of Basel Basel, Switzerland
| | - Cordula Nitsch
- Department of Biomedicine, Section of Functional Neuroanatomy, University of Basel Basel, Switzerland
| | - Ireneusz Piotr Maly
- Department of Biomedicine, Section of Functional Neuroanatomy, University of Basel Basel, Switzerland
| |
Collapse
|
209
|
Laghaei R, Yu ASL, Coalson RD. Water and ion permeability of a claudin model: A computational study. Proteins 2016; 84:305-15. [PMID: 26650625 DOI: 10.1002/prot.24969] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 11/02/2015] [Accepted: 11/29/2015] [Indexed: 01/27/2023]
Abstract
At present, the three-dimensional structure of the multimeric paracellular claudin pore is unknown. Using extant biophysical data concerning the size of the pore and permeation of water and cations through it, two three-dimensional models of the pore are constructed in silico. Molecular Dynamics (MD) calculations are then performed to compute water and sodium ion permeation fluxes under the influence of applied hydrostatic pressure. Comparison to experiment is made, under the assumption that the hydrostatic pressure applied in the simulations is equivalent to osmotic pressure induced in experimental measurements of water/ion permeability. One model, in which pore-lining charged is distributed evenly over a selectivity filter section 10-16 Å in length, is found to be generally consistent with experimental data concerning the dependence of water and ion permeation on channel pore diameter, pore length, and the sign and magnitude of pore lining charge. The molecular coupling mechanism between water and ion flow under conditions where hydrostatic pressure is applied is computationally elucidated.
Collapse
Affiliation(s)
- Rozita Laghaei
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260
| | - Alan S L Yu
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas
| | - Rob D Coalson
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, 15260
| |
Collapse
|
210
|
Claudin-21 Has a Paracellular Channel Role at Tight Junctions. Mol Cell Biol 2016; 36:954-64. [PMID: 26729464 DOI: 10.1128/mcb.00758-15] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/25/2015] [Indexed: 12/23/2022] Open
Abstract
Claudin protein family members, of which there are at least 27 in humans and mice, polymerize to form tight junctions (TJs) between epithelial cells, in a tissue- and developmental stage-specific manner. Claudins have a paracellular barrier function. In addition, certain claudins function as paracellular channels for small ions and/or solutes by forming selective pores at the TJs, although the specific claudins involved and their functional mechanisms are still in question. Here we show for the first time that claudin-21, which is more highly expressed in the embryonic than the postnatal stages, acts as a paracellular channel for small cations, such as Na(+), similar to the typical channel-type claudins claudin-2 and -15. Claudin-21 also allows the paracellular passage of larger solutes. Our findings suggest that claudin-21-based TJs allow the passage of small and larger solutes by both paracellular channel-based and some additional mechanisms.
Collapse
|
211
|
Markov AG, Falchuk EL, Kruglova NM, Radloff J, Amasheh S. Claudin expression in follicle-associated epithelium of rat Peyer's patches defines a major restriction of the paracellular pathway. Acta Physiol (Oxf) 2016; 216:112-9. [PMID: 26228735 DOI: 10.1111/apha.12559] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/19/2015] [Accepted: 07/24/2015] [Indexed: 12/17/2022]
Abstract
AIM Members of the tight junction protein family of claudins have been demonstrated to specifically determine paracellular permeability of the intestinal epithelium. In small intestinal mucosa, which is generally considered to be a leaky epithelium, Peyer's patches are a primary part of the immune system. The aim of this study was to analyse the tight junctional barrier of follicle-associated epithelium covering Peyer's patches (lymphoid follicles). METHODS Employing small intestinal tissue specimens of male Wistar rats, electrophysiological analyses including the Ussing chamber technique, marker flux measurements and one-path impedance spectroscopy were performed. Morphometry of HE-stained tissue sections was taken into account. Claudin expression and localization was analysed by immunoblotting and confocal laser scanning immunofluorescence microscopy. RESULTS Almost twofold higher parameters of epithelial and transepithelial tissue resistance and a markedly lower permeability for the paracellular permeability markers 4 and 20 kDa FITC-dextran were detected in follicle-associated epithelium compared to neighbouring villous epithelium. Analysis of claudin expression and localization revealed a stronger expression of major sealing proteins in follicle-associated epithelium, including claudin-1, claudin-4, claudin-5 and claudin-8. Therefore, the specific expression and localization of claudins is in accordance with barrier properties of follicle-associated epithelium vs. neighbouring villous epithelium. CONCLUSION We demonstrate that follicle-associated epithelium is specialized to ensure maximum restriction of the epithelial paracellular pathway in Peyer's patches by selective sealing of tight junctions. This results in an exclusive transcellular pathway of epithelial cells as the limiting and mandatory route for a controlled presentation of antigens to the underlying lymphocytes under physiological conditions.
Collapse
Affiliation(s)
- A. G. Markov
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - E. L. Falchuk
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - N. M. Kruglova
- Institute of General Physiology; Biological Faculty; St. Petersburg State University; St. Petersburg Russia
| | - J. Radloff
- Institute of Veterinary Physiology; Freie Universität Berlin; Berlin Germany
| | - S. Amasheh
- Institute of Veterinary Physiology; Freie Universität Berlin; Berlin Germany
- Institute of Clinical Physiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| |
Collapse
|
212
|
Ushida Y, Boonyapichest C, Suganuma H, Tanaka M, Matsui T. Paracellular Transport of Sulforaphane across Caco-2 Cell Monolayers. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2016. [DOI: 10.3136/fstr.22.127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | - Chutinan Boonyapichest
- Department of Bioscience and Biotechnology, Division of Bioresource and Bioenviromental Sciences, Faculty of Agriculture, Graduate School of Kyushu University
| | | | - Mitsuru Tanaka
- Department of Bioscience and Biotechnology, Division of Bioresource and Bioenviromental Sciences, Faculty of Agriculture, Graduate School of Kyushu University
| | - Toshiro Matsui
- Department of Bioscience and Biotechnology, Division of Bioresource and Bioenviromental Sciences, Faculty of Agriculture, Graduate School of Kyushu University
| |
Collapse
|
213
|
Conrad MP, Piontek J, Günzel D, Fromm M, Krug SM. Molecular basis of claudin-17 anion selectivity. Cell Mol Life Sci 2016; 73:185-200. [PMID: 26194246 PMCID: PMC11108356 DOI: 10.1007/s00018-015-1987-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/23/2015] [Accepted: 07/09/2015] [Indexed: 01/09/2023]
Abstract
Claudin-17 is a paracellular channel-forming tight junction protein. Unlike the cation channels claudin-2 and -15, claudin-17 forms a distinct anion-selective channel. Aim of this study was to determine the molecular basis of channel formation and charge selectivity of this protein. To achieve this, residues located in the extracellular loops (ECL) 1 and 2 of claudin-17 were substituted, preferably those whose charges differed in claudin-17 and in claudin-2 or -15. The respective mutants were stably expressed in MDCK C7 cells and their ability to form charge-selective channels was analyzed by measuring ion permeabilities and transepithelial electrical resistance. The functional data were combined with homology modeling of the claudin-17 protomer using the structure of claudin-15 as template. In ECL1, K65, R31, E48, and E44 were found to be stronger involved in Cldn17 channel function than the clustered R45, R56, R59, and R61. For K65, not only charge but also stereochemical properties were crucial for formation of the anion-selective channel. In ECL2, both Y149 and H154 were found to contribute to constitution of the anion channel in a distinct manner. In conclusion, we provide insight into the molecular mechanism of the formation of charge- and size-selective paracellular ion channels. In detail, we propose a hydrophilic furrow in the claudin-17 protomer spanning from a gap between the ends of TM2 and TM3 along R31, E48, and Y67 to a gap between K65 and S68 lining the anion channel.
Collapse
Affiliation(s)
- Marcel P Conrad
- Institute of Clinical Physiology, Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Jörg Piontek
- Institute of Clinical Physiology, Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Dorothee Günzel
- Institute of Clinical Physiology, Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Michael Fromm
- Institute of Clinical Physiology, Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Susanne M Krug
- Institute of Clinical Physiology, Charité, Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
| |
Collapse
|
214
|
De Santis S, Cavalcanti E, Mastronardi M, Jirillo E, Chieppa M. Nutritional Keys for Intestinal Barrier Modulation. Front Immunol 2015; 6:612. [PMID: 26697008 PMCID: PMC4670985 DOI: 10.3389/fimmu.2015.00612] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/22/2015] [Indexed: 12/14/2022] Open
Abstract
The intestinal tract represents the largest interface between the external environment and the human body. Nutrient uptake mostly happens in the intestinal tract, where the epithelial surface is constantly exposed to dietary antigens. Since inflammatory response toward these antigens may be deleterious for the host, a plethora of protective mechanisms take place to avoid or attenuate local damage. For instance, the intestinal barrier is able to elicit a dynamic response that either promotes or impairs luminal antigens adhesion and crossing. Regulation of intestinal barrier is crucial to control intestinal permeability whose increase is associated with chronic inflammatory conditions. The cross talk among bacteria, immune, and dietary factors is able to modulate the mucosal barrier function, as well as the intestinal permeability. Several nutritional products have recently been proposed as regulators of the epithelial barrier, even if their effects are in part contradictory. At the same time, the metabolic function of the microbiota generates new products with different effects based on the dietary content. Besides conventional treatments, novel therapies based on complementary nutrients are now growing. Fecal therapy has been recently used for the clinical treatment of refractory Clostridium difficile infection instead of the classical antibiotic therapy. In the present review, we will outline the epithelial response to nutritional components derived from dietary intake and microbial fermentation focusing on the consequent effects on the integrity of the epithelial barrier.
Collapse
Affiliation(s)
- Stefania De Santis
- Laboratory of Experimental Immunopathology, IRCCS "De Bellis" , Castellana Grotte , Italy
| | - Elisabetta Cavalcanti
- Laboratory of Experimental Immunopathology, IRCCS "De Bellis" , Castellana Grotte , Italy
| | - Mauro Mastronardi
- Department of Gastroenterology, IRCCS "De Bellis" , Castellana Grotte , Italy
| | - Emilio Jirillo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari , Bari , Italy
| | - Marcello Chieppa
- Laboratory of Experimental Immunopathology, IRCCS "De Bellis" , Castellana Grotte , Italy ; Istituto Comprensivo Bregante-Volta , Monopoli , Italy
| |
Collapse
|
215
|
Bossus MC, Madsen SS, Tipsmark CK. Functional dynamics of claudin expression in Japanese medaka (Oryzias latipes): Response to environmental salinity. Comp Biochem Physiol A Mol Integr Physiol 2015; 187:74-85. [DOI: 10.1016/j.cbpa.2015.04.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 04/30/2015] [Accepted: 04/30/2015] [Indexed: 11/16/2022]
|
216
|
Hu CAA, Hou Y, Yi D, Qiu Y, Wu G, Kong X, Yin Y. Autophagy and tight junction proteins in the intestine and intestinal diseases. ACTA ACUST UNITED AC 2015; 1:123-127. [PMID: 29767173 PMCID: PMC5945941 DOI: 10.1016/j.aninu.2015.08.014] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 08/25/2015] [Indexed: 12/22/2022]
Abstract
The intestinal epithelium (IE) forms an indispensible barrier and interface between the intestinal interstitium and the luminal environment. The IE regulates water, ion and nutrient transport while providing a barrier against toxins, pathogens (bacteria, fungi and virus) and antigens. The apical intercellular tight junctions (TJ) are responsible for the paracellular barrier function and regulate trans-epithelial flux of ions and solutes between adjacent cells. Increased intestinal permeability caused by defects in the IE TJ barrier is considered an important pathogenic factor for the development of intestinal inflammation, diarrhea and malnutrition in humans and animals. In fact, defects in the IE TJ barrier allow increased antigenic penetration, resulting in an amplified inflammatory response in inflammatory bowel disease (IBD), necrotizing enterocolitis and ischemia-reperfusion injury. Conversely, the beneficial enhancement of the intestinal TJ barrier has been shown to resolve intestinal inflammation and apoptosis in both animal models of IBD and human IBD. Autophagy (self-eating mechanism) is an intracellular lysosome-dependent degradation and recycling pathway essential for cell survival and homeostasis. Dysregulated autophagy has been shown to be directly associated with many pathological processes, including IBD. Importantly, the crosstalk between IE TJ and autophagy has been revealed recently. We showed that autophagy enhanced IE TJ barrier function by increasing transepithelial resistance and reducing the paracellular permeability of small solutes and ions, which is, in part, by targeting claudin-2, a cation-selective, pore-forming, transmembrane TJ protein, for lysosome (autophagy)-mediated degradation. Interestingly, previous studies have shown that the inflamed intestinal mucosa in patients with active IBD has increased claudin-2 expression. In addition, inflammatory cytokines (for example, tumor necrosis factor-α, interleukin-6, interleukin-13, and interleukin-17) whose levels are increased in IBD patients cause an increase in claudin-2 expression and a claudin-2-dependent increase in TJ permeability. Thus, the role of claudin-2 in intestinal pathological processes has been attributed, in part, to the increase of intestinal TJ permeability. Claudin-2 represents a new therapeutic target in treating IBD, diarrhea and malnutrition in animals and humans.
Collapse
Affiliation(s)
- Chien-An A. Hu
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque 87131, USA
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China
- Corresponding author.
| | - Yongqing Hou
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China
- Corresponding author.
| | - Dan Yi
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China
| | - Yinsheng Qiu
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China
| | - Guoyao Wu
- Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan 430023, China
- Department of Animal Science, Texas A&M University, College Station 77843, USA
| | - Xiangfeng Kong
- Institute of Subtropical Agriculture, Chinese Academy of Engineering, Changsha 410125, China
| | - Yulong Yin
- Institute of Subtropical Agriculture, Chinese Academy of Engineering, Changsha 410125, China
- Corresponding author.
| |
Collapse
|
217
|
Brown EM, Wlodarska M, Willing BP, Vonaesch P, Han J, Reynolds LA, Arrieta MC, Uhrig M, Scholz R, Partida O, Borchers CH, Sansonetti PJ, Finlay BB. Diet and specific microbial exposure trigger features of environmental enteropathy in a novel murine model. Nat Commun 2015; 6:7806. [PMID: 26241678 PMCID: PMC4532793 DOI: 10.1038/ncomms8806] [Citation(s) in RCA: 154] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 06/15/2015] [Indexed: 01/07/2023] Open
Abstract
Environmental enteropathy (EE) is a subclinical chronic inflammatory disease of the small intestine and has a profound impact on the persistence of childhood malnutrition worldwide. However, the aetiology of the disease remains unknown and no animal model exists to date, the creation of which would aid in understanding this complex disease. Here we demonstrate that early-life consumption of a moderately malnourished diet, in combination with iterative oral exposure to commensal Bacteroidales species and Escherichia coli, remodels the murine small intestine to resemble features of EE observed in humans. We further report the profound changes that malnutrition imparts on the small intestinal microbiota, metabolite and intraepithelial lymphocyte composition, along with the susceptibility to enteric infection. Our findings provide evidence indicating that both diet and microbes combine to contribute to the aetiology of EE, and describe a novel murine model that can be used to elucidate the mechanisms behind this understudied disease. Environmental enteropathy is a disorder of the small intestine that contributes to the persistence of childhood malnutrition worldwide. Here, Brown et al. show in mice that early-life malnourishment, in combination with exposure to commensal bacteria, remodels the small intestine to resemble features of the disease.
Collapse
Affiliation(s)
- Eric M Brown
- 1] Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada [2] Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Marta Wlodarska
- 1] Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada [2] Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Benjamin P Willing
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5
| | - Pascale Vonaesch
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, Paris 75724, France
| | - Jun Han
- The UVic-Genome British Columbia Proteomics Centre, University of Victoria, Victoria, British Columbia, Canada V8Z 7X8
| | - Lisa A Reynolds
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Marie-Claire Arrieta
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Marco Uhrig
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Roland Scholz
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Oswaldo Partida
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| | - Christoph H Borchers
- 1] The UVic-Genome British Columbia Proteomics Centre, University of Victoria, Victoria, British Columbia, Canada V8Z 7X8 [2] Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada V8P 5C2
| | | | - B Brett Finlay
- 1] Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada [2] Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4 [3] Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
| |
Collapse
|
218
|
Madsen SS, Engelund MB, Cutler CP. Water transport and functional dynamics of aquaporins in osmoregulatory organs of fishes. THE BIOLOGICAL BULLETIN 2015; 229:70-92. [PMID: 26338871 DOI: 10.1086/bblv229n1p70] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Aquaporins play distinct roles for water transport in fishes as they do in mammals-both at the cellular, organ, and organismal levels. However, with over 32,000 known species of fishes inhabiting almost every aquatic environment, from tidal pools, small mountain streams, to the oceans and extreme salty desert lakes, the challenge to obtain consensus as well as specific knowledge about aquaporin physiology in these vertebrate clades is overwhelming. Because the integumental surfaces of these animals are in intimate contact with the surrounding milieu, passive water loss and uptake represent two of the major osmoregulatory challenges that need compensation. However, neither obligatory nor regulatory water transport nor their mechanisms have been elucidated to the same degree as, for example, ion transport in fishes. Currently fewer than 60 papers address fish aquaporins. Most of these papers identify "what is present" and describe tissue expression patterns in various teleosts. The agnathans, chondrichthyans, and functionality of fish aquaporins generally have received little attention. This review emphasizes the functional physiology of aquaporins in fishes, focusing on transepithelial water transport in osmoregulatory organs in euryhaline species - primarily teleosts, but covering other taxonomic groups as well. Most current knowledge comes from teleosts, and there is a strong need for related information on older fish clades. Our survey aims to stimulate new, original research in this area and to bring together new collaborations across disciplines.
Collapse
Affiliation(s)
- Steffen S Madsen
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark;
| | - Morten B Engelund
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Christopher P Cutler
- Department of Biology, Georgia Southern University, P.O. Box 8042, Statesboro, Georgia 30460
| |
Collapse
|
219
|
Zhang YG, Wu S, Lu R, Zhou D, Zhou J, Carmeliet G, Petrof E, Claud EC, Sun J. Tight junction CLDN2 gene is a direct target of the vitamin D receptor. Sci Rep 2015. [PMID: 26212084 PMCID: PMC4650691 DOI: 10.1038/srep10642] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The breakdown of the intestinal barrier is a common manifestation of many diseases. Recent evidence suggests that vitamin D and its receptor VDR may regulate intestinal barrier function. Claudin-2 is a tight junction protein that mediates paracellular water transport in intestinal epithelia, rendering them “leaky”. Using whole body VDR-/- mice, intestinal epithelial VDR conditional knockout (VDRΔIEC) mice, and cultured human intestinal epithelial cells, we demonstrate here that the CLDN2 gene is a direct target of the transcription factor VDR. The Caudal-Related Homeobox (Cdx) protein family is a group of the transcription factor proteins which bind to DNA to regulate the expression of genes. Our data showed that VDR-enhances Claudin-2 promoter activity in a Cdx1 binding site-dependent manner. We further identify a functional vitamin D response element (VDRE) 5΄-AGATAACAAAGGTCA-3΄ in the Cdx1 site of the Claudin-2 promoter. It is a VDRE required for the regulation of Claudin-2 by vitamin D. Absence of VDR decreased Claudin-2 expression by abolishing VDR/promoter binding. In vivo, VDR deletion in intestinal epithelial cells led to significant decreased Claudin-2 in VDR-/- and VDRΔIEC mice. The current study reveals an important and novel mechanism for VDR by regulation of epithelial barriers.
Collapse
Affiliation(s)
- Yong-guo Zhang
- Department of Biochemistry, Rush University, Chicago, Illinois, USA
| | - Shaoping Wu
- Department of Biochemistry, Rush University, Chicago, Illinois, USA
| | - Rong Lu
- Department of Biochemistry, Rush University, Chicago, Illinois, USA
| | - David Zhou
- Department of Pathology, University of Rochester, Rochester, New York, USA
| | - Jingsong Zhou
- Department of Physiology, Kansas City University of Medicine and Bioscience, Kansas City, Missouri, USA
| | - Geert Carmeliet
- Lab of Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Elaine Petrof
- Department of Medicine, GI Diseases Research Unit and Division of Infectious Diseases, Queen's University, Ontario, Canada
| | - Erika C Claud
- Departments of Pediatrics and Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Jun Sun
- 1] Department of Biochemistry, Rush University, Chicago, Illinois, USA [2] Department of Pathology, University of Rochester, Rochester, New York, USA
| |
Collapse
|
220
|
Sexual maturation and changes in water and salt transport components in the kidney and intestine of three-spined stickleback (Gasterosteus aculeatus L.). Comp Biochem Physiol A Mol Integr Physiol 2015; 188:107-19. [PMID: 26135640 DOI: 10.1016/j.cbpa.2015.06.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 06/15/2015] [Accepted: 06/19/2015] [Indexed: 12/15/2022]
Abstract
Mature three-spined stickleback males use spiggin threads secreted from their kidney to glue together nest material. This requires strongly hypertrophied renal proximal tubular cells, which compromises renal osmoregulatory function during the breeding period. Experimental evidence suggests that the intestine takes over hypotonic fluid secretion at that stage but the mechanism is unexplored. To unravel the molecular mechanism we analyzed and compared transcript levels of several membrane proteins involved in water and salt transport in intestinal and renal tissues, in non-mature males (NM), mature males (MM), and mature females (MF). Aquaporin paralogs aqp1a, -3a, -8aa, -8ab, -10a, and -10b, two Na(+),K(+)-ATPase alpha-1 subunit isoforms (nka547, nka976), Na(+),K(+),2Cl(-)-, and Na(+),Cl(-)-cotransporters (nkcc1a, nkcc2, ncc), the cystic fibrosis transmembrane conductance regulator (cftr) and two claudin isoforms (cldn2, cldn15a) were expressed in the intestine and kidney in all groups. There were no differences in aqp and cldn expression between intestines of NM and MM; nkcc2 was lower and nka levels tended to be higher in intestines of MM than in NM. In the kidney, aqp1 and aqp8ab levels were lower in MM than in NM, whereas aqp3a, nkcc1a, cldn15a, and spiggin were markedly elevated. This was accompanied by marked hypertrophy of kidney tubules in MM. The data support an altered kidney function in terms of water handling in mature males, whereas there was no support for modified trans-epithelial water permeability or salt-secretory activity in the intestine of mature males. Salt-absorptive activity in the intestine may, however, be down-regulated during male maturation.
Collapse
|
221
|
Claudin-related intestinal diseases. Semin Cell Dev Biol 2015; 42:30-8. [PMID: 25999319 DOI: 10.1016/j.semcdb.2015.05.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 05/09/2015] [Accepted: 05/12/2015] [Indexed: 02/07/2023]
Abstract
With up to 200 m(2) the human intestine is the organ with the largest absorptive surface of the body. It is lined by a single layer of epithelial cells that separates the host from the environment. The intestinal epithelium provides both, selective absorption of nutrients, ions, and water but also a highly effective barrier function which includes the first line of defense against environmental antigens. The paracellular part of this barrier function is provided by tight junction (TJ) proteins, especially the large family of claudins. Changes in abundance or molecular structure of claudins can generally result in three typical effects, (i) decreased absorptive passage, (ii) increased secretory passage of small solutes and water causing leak flux diarrhea and (iii) increased absorptive passage of macromolecules which may induce inflammatory processes. Several intestinal diseases are associated with such changes that can result in intestinal inflammation and symptoms like weight loss, abdominal pain or diarrhea. This review summarizes our current knowledge on barrier dysfunction and claudin dysregulation in several intestinal diseases gastroenterologists are often faced with, like inflammatory bowel disease, microscopic colitis, celiac disease, irritable bowel syndrome, gallstones and infectious diseases like HIV enteropathy, Campylobacter jejuni and Clostridium perfringens infection.
Collapse
|
222
|
Amoozadeh Y, Dan Q, Xiao J, Waheed F, Szászi K. Tumor necrosis factor-α induces a biphasic change in claudin-2 expression in tubular epithelial cells: role in barrier functions. Am J Physiol Cell Physiol 2015; 309:C38-50. [PMID: 25948735 DOI: 10.1152/ajpcell.00388.2014] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 05/02/2015] [Indexed: 01/04/2023]
Abstract
The inflammatory cytokine tumor necrosis factor-α (TNF-α) is a pathogenic factor in acute and chronic kidney disease. TNF-α is known to alter expression of epithelial tight junction (TJ) proteins; however, the underlying mechanisms and the impact of this effect on epithelial functions remain poorly defined. Here we describe a novel biphasic effect of TNF-α on TJ protein expression. In LLC-PK1 tubular cells, short-term (1-6 h) TNF-α treatment selectively elevated the expression of the channel-forming TJ protein claudin-2. In contrast, prolonged (>8 h) TNF-α treatment caused a marked downregulation in claudin-2 and an increase in claudin-1, -4, and -7. The early increase and the late decrease in claudin-2 expression involved distinct mechanisms. TNF-α slowed claudin-2 degradation through ERK, causing the early increase. This increase was also mediated by the EGF receptor and RhoA and Rho kinase. In contrast, prolonged TNF-α treatment reduced claudin-2 mRNA levels and promoter activity independent from these signaling pathways. Electric Cell-substrate Impedance Sensing measurements revealed that TNF-α also exerted a biphasic effect on transepithelial resistance (TER) with an initial decrease and a late increase. Thus there was a good temporal correlation between TNF-α-induced claudin-2 protein and TER changes. Indeed, silencing experiments showed that the late TER increase was at least in part caused by reduced claudin-2 expression. Surprisingly, however, claudin-2 silencing did not prevent the early TER drop. Taken together, the TNF-α-induced changes in claudin-2 levels might contribute to TER changes and could also play a role in newly described functions of claudin-2 such as proliferation regulation.
Collapse
Affiliation(s)
- Yasaman Amoozadeh
- Keenan Research Centre for Biomedical Science of the St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| | - Qinghong Dan
- Keenan Research Centre for Biomedical Science of the St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| | - Jenny Xiao
- Keenan Research Centre for Biomedical Science of the St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| | - Faiza Waheed
- Keenan Research Centre for Biomedical Science of the St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| | - Katalin Szászi
- Keenan Research Centre for Biomedical Science of the St. Michael's Hospital and Department of Surgery, University of Toronto, Ontario, Canada
| |
Collapse
|
223
|
Molina-Jijón E, Rodríguez-Muñoz R, Namorado MDC, Bautista-García P, Medina-Campos ON, Pedraza-Chaverri J, Reyes JL. All- trans retinoic acid prevents oxidative stress-induced loss of renal tight junction proteins in type-1 diabetic model. J Nutr Biochem 2015; 26:441-54. [DOI: 10.1016/j.jnutbio.2014.11.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 11/07/2014] [Accepted: 11/19/2014] [Indexed: 12/31/2022]
|
224
|
Transcriptional regulators of claudins in epithelial tight junctions. Mediators Inflamm 2015; 2015:219843. [PMID: 25948882 PMCID: PMC4407569 DOI: 10.1155/2015/219843] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 09/22/2014] [Accepted: 10/03/2014] [Indexed: 02/06/2023] Open
Abstract
Human gastrointestinal tract is covered by a monolayer of specialized epithelial cells that constitute a protective barrier surface to external toxic and infectious agents along with metabolic and digestive functions. Intercellular junctions, among epithelial cells, such as desmosomes, adherens, gap, and tight junctions (TJs), not only provide mechanical integrity but also limit movement of molecules across the monolayer. TJ is a complex structure composed of approximately 35 different proteins that interact with each other at the apical side of two adjacent epithelial cells. Claudin family proteins are important members of TJ with so far 24 known isoforms in different species. Claudins are structural proteins of TJ that help to control the paracellular movement by forming fence and barrier across the epithelial monolayer. Altered function of claudins is implicated in different form of cancers, inflammatory bowel diseases (IBDs), and leaky diarrhea. Based on their significant role in the molecular architecture of TJ, diversity, and disease association, further understanding about claudin family proteins and their genetic/epigenetic regulators is indispensable.
Collapse
|
225
|
Abstract
The kidney filters vast quantities of Na at the glomerulus but excretes a very small fraction of this Na in the final urine. Although almost every nephron segment participates in the reabsorption of Na in the normal kidney, the proximal segments (from the glomerulus to the macula densa) and the distal segments (past the macula densa) play different roles. The proximal tubule and the thick ascending limb of the loop of Henle interact with the filtration apparatus to deliver Na to the distal nephron at a rather constant rate. This involves regulation of both filtration and reabsorption through the processes of glomerulotubular balance and tubuloglomerular feedback. The more distal segments, including the distal convoluted tubule (DCT), connecting tubule, and collecting duct, regulate Na reabsorption to match the excretion with dietary intake. The relative amounts of Na reabsorbed in the DCT, which mainly reabsorbs NaCl, and by more downstream segments that exchange Na for K are variable, allowing the simultaneous regulation of both Na and K excretion.
Collapse
Affiliation(s)
- Lawrence G Palmer
- Department of Physiology and Biophysics, Weill-Cornell Medical College, New York, New York; and
| | - Jürgen Schnermann
- Kidney Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
226
|
Brandner JM, Zorn-Kruppa M, Yoshida T, Moll I, Beck LA, De Benedetto A. Epidermal tight junctions in health and disease. Tissue Barriers 2015; 3:e974451. [PMID: 25838981 DOI: 10.4161/21688370.2014.974451] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 10/04/2014] [Indexed: 01/21/2023] Open
Abstract
The skin, the largest organ of the body, is an essential barrier that under homeostatic conditions efficiently protects and/or minimizes damage from both environmental (e.g. microorganisms, physical trauma, ultraviolet radiation) and endogenous (e.g., cancers, inflammation) factors. This formidable barrier function resides mainly in the epidermis, a dynamic, highly-stratified epithelium. The epidermis has 2 major barrier structures: stratum corneum, the outmost layer and tight junctions, intercellular junctions that seal adjacent keratinocytes in the stratum granulosum, found below the stratum corneum. In recent years there have been significant advances in our understanding of tight junction function, composition and regulation. Herein we review what is known about tight junctions in healthy skin and keratinocyte culture systems and highlight the dynamic crosstalk observed between tight junctions and the cutaneous immune system. Finally we discuss the preliminary observations suggesting that tight junction function or protein expression may be relevant for the pathogenesis of a number of common cutaneous inflammatory and neoplastic conditions.
Collapse
Key Words
- AD, atopic dermatitis
- AMP, antimicrobial peptides
- Cldn, claudin
- DC, dendritic cells
- FLG, filaggrin
- JAM, junctional adhesion molecule
- LC, Langerhans cells
- MM, malignant melanoma
- PRR, pattern recognition receptor
- PS, psoriasis
- SCC, squamous cell carcinoma; SC, stratum corneum
- SG, stratum granulosum
- SNP, single nucleotide polymorphism
- TER, TransEpithelial Electrical Resistance
- TJ, tight junction
- TLR, Toll-like receptor
- Th, T helper
- ZO-1, zonula occludens 1
- claudins
- skin barrier
- skin immune system
- skin innate barrier
- tight junction
Collapse
Affiliation(s)
- J M Brandner
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - M Zorn-Kruppa
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - T Yoshida
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
| | - I Moll
- Department of Dermatology and Venereology; University Hospital Hamburg-Eppendorf ; Hamburg, Germany
| | - L A Beck
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
| | - A De Benedetto
- Department of Dermatology; University of Rochester Medical Center ; Rochester, NY USA
| |
Collapse
|
227
|
Luettig J, Rosenthal R, Barmeyer C, Schulzke JD. Claudin-2 as a mediator of leaky gut barrier during intestinal inflammation. Tissue Barriers 2015; 3:e977176. [PMID: 25838982 DOI: 10.4161/21688370.2014.977176] [Citation(s) in RCA: 183] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 10/10/2014] [Indexed: 02/07/2023] Open
Abstract
The epithelial tight junction determines the paracellular water and ion movement in the intestine and also prevents uptake of larger molecules, including antigens, in an uncontrolled manner. Claudin-2, one of the 27 mammalian claudins regulating that barrier function, forms a paracellular channel for small cations and water. It is typically expressed in leaky epithelia like proximal nephron and small intestine and provides a major pathway for the paracellular transport of sodium, potassium, and fluid. In intestinal inflammation (Crohn's disease, ulcerative colitis), immune-mediated diseases (celiac disease), and infections (HIV enteropathy), claudin-2 is upregulated in small and large intestine and contributes to diarrhea via a leak flux mechanism. In parallel to that upregulation, other epithelial and tight junctional features are altered and the luminal uptake of antigenic macromolecules is enhanced, for which claudin-2 may be partially responsible through induction of tight junction strand discontinuities.
Collapse
Key Words
- AP, activator protein
- CARD15, caspase recruitment domain-containing protein 15
- Crohn's disease
- DSS, dextran sodium sulfate
- ECL, extracellular loop
- ERK, extracellular-regulated kinase
- HIV
- HIV, human immunodeficiency virus
- HNF, hepatocyte nuclear factor
- IBD, inflammatory bowel disease
- IFN, interferon
- IFNγ
- IL, interleukin
- JAM, junctional adhesion molecule
- JNK, c-jun N-terminal kinase
- LPS, lipopolysaccharides
- MAPK, mitogen-activated protein kinase
- MDCK, Madine Darby canine kidney
- MLC, myosin light chain
- NFκB, nuclear factor kappa B
- NOD2, nucleotide-binding oligomerization domain-containing protein 2
- PI3K, phosphatidyl-inositol-3-kinase
- ROCK, Rho kinase
- Rho, ras homolog
- STAT, signal transducers and activators of transcription
- TEER, transepithelial electrical resistance
- TJ, tight junction
- TNBS, 2,4,6-trinitrobenzene sulfonic acid
- TNF, tumor necrosis factor
- TNFα
- Tat, trans-activator of transcription
- Vpr, viral protein r; ZO, zonula occludens
- celiac disease
- claudin-2
- gp, glycoprotein
- inflammatory bowel disease
- tight junction
- ulcerative colitis
Collapse
Affiliation(s)
- J Luettig
- Institute of Clinical Physiology; Department of Gastroenterology; Charité ; Berlin, Germany
| | - R Rosenthal
- Institute of Clinical Physiology; Department of Gastroenterology; Charité ; Berlin, Germany
| | - C Barmeyer
- Institute of Clinical Physiology; Department of Gastroenterology; Charité ; Berlin, Germany
| | - J D Schulzke
- Institute of Clinical Physiology; Department of Gastroenterology; Charité ; Berlin, Germany
| |
Collapse
|
228
|
Markov AG, Aschenbach JR, Amasheh S. Claudin clusters as determinants of epithelial barrier function. IUBMB Life 2015; 67:29-35. [PMID: 25788154 DOI: 10.1002/iub.1347] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Accepted: 01/05/2015] [Indexed: 12/18/2022]
Abstract
Claudins are tetraspan tight junction proteins which have been attributed to primarily determine epithelial barrier function in a wide variety of different organs and tissues. Among this protein family with currently 27 members, single claudins contribute in an organ- and tissue-specific manner to defined properties such as cation-, anion- or water-selective pore functions, sealing functions or ambiguous functions. As the size of tight junction strand particles visualized by freeze-fracture electron microscopy have a diameter of approximately 10 nm, multimeric assembly of tight junction proteins appears to be a basic principle for barrier formation. Moreover, expression patterns of different tissues showed that single claudins appear to specifically co-localize with other claudins, which indicates a cluster formation within tight junction strand particles with a fixed stoichiometry. This review provides a critical view on the current understanding of tight junction protein co-localization within strands. We analyze how tissue specific differences of claudin functions could be dependent on their specific partners for barrier formation. Furthermore, a model of claudin clusters as structural and functional units within tight junction strands is provided.
Collapse
Affiliation(s)
- Alexander G Markov
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | | | | |
Collapse
|
229
|
Tokuda S, Furuse M. Claudin-2 knockout by TALEN-mediated gene targeting in MDCK cells: claudin-2 independently determines the leaky property of tight junctions in MDCK cells. PLoS One 2015; 10:e0119869. [PMID: 25781928 PMCID: PMC4363821 DOI: 10.1371/journal.pone.0119869] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 02/02/2015] [Indexed: 11/23/2022] Open
Abstract
Tight junctions (TJs) regulate the movements of substances through the paracellular pathway, and claudins are major determinants of TJ permeability. Claudin-2 forms high conductive cation pores in TJs. The suppression of claudin-2 expression by RNA interference in Madin-Darby canine kidney (MDCK) II cells (a low-resistance strain of MDCK cells) was shown to induce a three-fold increase in transepithelial electrical resistance (TER), which, however, was still lower than in high-resistance strains of MDCK cells. Because RNA interference-mediated knockdown is not complete and only reduces gene function, we considered the possibility that the remaining claudin-2 expression in the knockdown study caused the lower TER in claudin-2 knockdown cells. Therefore, we investigated the effects of claudin-2 knockout in MDCK II cells by establishing claudin-2 knockout clones using transcription activator-like effector nucleases (TALENs), a recently developed genome editing method for gene knockout. Surprisingly, claudin-2 knockout increased TER by more than 50-fold in MDCK II cells, and TER values in these cells (3000–4000 Ω·cm2) were comparable to those in the high-resistance strains of MDCK cells. Claudin-2 re-expression restored the TER of claudin-2 knockout cells dependent upon claudin-2 protein levels. In addition, we investigated the localization of claudin-1, -2, -3, -4, and -7 at TJs between control MDCK cells and their respective knockout cells using their TALENs. Claudin-2 and -7 were less efficiently localized at TJs between control and their knockout cells. Our results indicate that claudin-2 independently determines the ‘leaky’ property of TJs in MDCK II cells and suggest the importance of knockout analysis in cultured cells.
Collapse
Affiliation(s)
- Shinsaku Tokuda
- Division of Cell Biology, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650–0017, Japan
- * E-mail:
| | - Mikio Furuse
- Division of Cell Biology, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650–0017, Japan
- Division of Cerebral Structure, National Institute for Physiological Sciences, Okazaki 444–8787, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444–8585, Japan
| |
Collapse
|
230
|
Lu R, Dalgalan D, Mandell EK, Parker SS, Ghosh S, Wilson JM. PKCι interacts with Rab14 and modulates epithelial barrier function through regulation of claudin-2 levels. Mol Biol Cell 2015; 26:1523-31. [PMID: 25694446 PMCID: PMC4395131 DOI: 10.1091/mbc.e14-12-1613] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 02/10/2015] [Indexed: 01/03/2023] Open
Abstract
PKCι is essential for the establishment of epithelial polarity and the normal assembly of tight junctions. We find that PKCι knockdown does not compromise the steady-state distribution of most tight junction proteins but results in increased transepithelial resistance (TER) and decreased paracellular permeability. Analysis of the levels of tight junction components demonstrates that claudin-2 protein levels are decreased. However, other tight junction proteins, such as claudin-1, ZO-1, and occludin, are unchanged. Incubation with an aPKC pseudosubstrate recapitulates the phenotype of PKCι knockdown, including increased TER and decreased levels of claudin-2. In addition, overexpression of PKCι results in increased claudin-2 levels. ELISA and coimmunoprecipitation show that the TGN/endosomal small GTPase Rab14 and PKCι interact directly. Immunolabeling shows that PKCι and Rab14 colocalize in both intracellular puncta and at the plasma membrane and that Rab14 expression is required for normal PKCι distribution in cysts in 3D culture. We showed previously that knockdown of Rab14 results in increased TER and decreased claudin-2. Our results suggest that Rab14 and aPKC interact to regulate trafficking of claudin-2 out of the lysosome-directed pathway.
Collapse
Affiliation(s)
- Ruifeng Lu
- Department of Cellular and Molecular Medicine, University of Arizona College of Medicine, Tucson, AZ 85724
| | - Dogukan Dalgalan
- Department of Cellular and Molecular Medicine, University of Arizona College of Medicine, Tucson, AZ 85724
| | - Edward K Mandell
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06511
| | - Sara S Parker
- Department of Cellular and Molecular Medicine, University of Arizona College of Medicine, Tucson, AZ 85724
| | - Sourav Ghosh
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06511
| | - Jean M Wilson
- Department of Cellular and Molecular Medicine, University of Arizona College of Medicine, Tucson, AZ 85724
| |
Collapse
|
231
|
Hereditary barrier-related diseases involving the tight junction: lessons from skin and intestine. Cell Tissue Res 2015; 360:723-48. [DOI: 10.1007/s00441-014-2096-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 12/11/2014] [Indexed: 02/07/2023]
|
232
|
Smith NJ, Hinley J, Varley CL, Eardley I, Trejdosiewicz LK, Southgate J. The human urothelial tight junction: claudin 3 and the ZO-1α + switch. Bladder (San Franc) 2015; 2:e9. [PMID: 26269793 PMCID: PMC4530542 DOI: 10.14440/bladder.2015.33] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Objective Tight junctions are multicomponent structures, with claudin proteins defining paracellular permeability. Claudin 3 is a candidate for the exceptional “tightness” of human urothelium, being localised to the terminal tight junction (TJ) of superficial cells. Our aim was to determine whether claudin 3 plays an instigating and/or a functional role in the urothelial TJ. Materials and Methods Normal human urothelial (NHU) cells maintained as non-immortalised cell lines were retrovirally-transduced to over-express or silence claudin 3 expression. Stable sublines induced to stratify or differentiate were assessed for TJ formation by immunocytochemistry and transepithelial electrical resistance (TER). Expression of claudin 3, ZO-1 and ZO-1α+ was examined in native urothelium by immunohistochemistry. Results Claudin 3 expression was associated with differentiation and development of a tight barrier and along with ZO-1 and ZO-1α+ was localised to the apical tight junction in native urothelium. Knockdown of claudin 3 inhibited formation of a tight barrier in three independent cell lines, however, overexpression of claudin 3 was not sufficient to induce tight barrier development in the absence of differentiation. A differentiation-dependent induction of the ZO-1α+ isoform was found to coincide with barrier formation. Whereas claudin 3 overexpression did not induce the switch to co-expression of ZO-1α−/ZO-1α+, claudin 3 knockdown decreased localisation of ZO-1 to the TJ and resulted in compromised barrier function. Conclusions Urothelial cytodifferentiation is accompanied by induction of claudin 3 which is essential for the development of a terminal TJ. A coordinated switch to the ZO-1α+ isotype was also observed and for the first time may indicate that ZO-1α+ is involved in the structural assembly and function of the urothelial terminal TJ.
Collapse
Affiliation(s)
- Nicholas J Smith
- Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, York YO10 5DD, United Kingdom ; Pyrah Department of Urology, St James's University Hospital, Leeds LS9 7TF, United Kingdom
| | - Jennifer Hinley
- Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Claire L Varley
- Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Ian Eardley
- Pyrah Department of Urology, St James's University Hospital, Leeds LS9 7TF, United Kingdom
| | - Ludwik K Trejdosiewicz
- Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, York YO10 5DD, United Kingdom
| | - Jennifer Southgate
- Jack Birch Unit of Molecular Carcinogenesis, Department of Biology, University of York, York YO10 5DD, United Kingdom
| |
Collapse
|
233
|
Kamińska K, Szczylik C, Bielecka ZF, Bartnik E, Porta C, Lian F, Czarnecka AM. The role of the cell-cell interactions in cancer progression. J Cell Mol Med 2015; 19:283-96. [PMID: 25598217 PMCID: PMC4407603 DOI: 10.1111/jcmm.12408] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 07/18/2014] [Indexed: 12/11/2022] Open
Abstract
In the field of cancer research, scientific investigations are based on analysing differences in the secretome, the proteome, the transcriptome, the expression of cell surface molecules, and the deregulation of signal transduction pathways between neoplastic and normal cells. Accumulating evidence indicates a crucial role in carcinogenesis concerning not only stromal cells but also normal cells from target organs and tissue where tumours emerge. The tumour microenvironment (TME) definitively plays an important role in regulating neighbouring cell behaviour. To date, limited attention has been focused upon interactions between cancer cells and normal cells. This review concentrates on the interactions between stromal and healthy cells from the TME in cancer development. In the article, the authors also describe mutations, genes and proteins expression pattern that are involved in tumour development in target organ.
Collapse
Affiliation(s)
- Katarzyna Kamińska
- Department of Oncology with Laboratory of Molecular Oncology, Military Institute of Medicine, Warsaw, Poland
| | | | | | | | | | | | | |
Collapse
|
234
|
Abstract
Claudins are tight-junction membrane proteins that function as both pores and barriers in the paracellular pathway in epithelial cells. In the kidney, claudins determine the permeability and selectivity of different nephron segments along the renal tubule. In the proximal tubule, claudins have a role in the bulk reabsorption of salt and water. In the thick ascending limb, claudins are important for the reabsorption of calcium and magnesium and are tightly regulated by the calcium-sensing receptor. In the distal nephron, claudins need to form cation barriers and chloride pores to facilitate electrogenic sodium reabsorption and potassium and acid secretion. Aldosterone and the with-no-lysine (WNK) proteins likely regulate claudins to fine-tune distal nephron salt transport. Genetic mutations in claudin-16 and -19 cause familial hypomagnesemic hypercalciuria with nephrocalcinosis, whereas polymorphisms in claudin-14 are associated with kidney stone risk. It is likely that additional roles for claudins in the pathogenesis of other types of kidney diseases have yet to be uncovered.
Collapse
Affiliation(s)
- Alan S L Yu
- Division of Nephrology and Hypertension, and the Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas
| |
Collapse
|
235
|
Xiang RL, Mei M, Cong X, Li J, Zhang Y, Ding C, Wu LL, Yu GY. Claudin-4 is required for AMPK-modulated paracellular permeability in submandibular gland cells. J Mol Cell Biol 2014; 6:486-97. [PMID: 25503106 DOI: 10.1093/jmcb/mju048] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Tight junction plays an important role in mediating paracellular permeability in epithelia. We previously found that activation of AMP-activated protein kinase (AMPK) increased saliva secretion by modulating paracellular permeability in submandibular glands. However, the molecular mechanisms underlying AMPK-modulated paracellular permeability are unknown. In this study, we found that AICAR, an AMPK agonist, increased saliva secretion in the isolated rat submandibular glands, decreased transepithelial electrical resistance (TER), and increased 4 kDa FITC-dextran flux in cultured SMG-C6 cells. AICAR also induced redistribution of tight junction protein claudin-4, but not claudin-1, claudin-3, occludin, or ZO-1, from the cytoplasm to the membrane. Moreover, knockdown of claudin-4 by shRNA suppressed while claudin-4 re-expression restored the TER and 4 kDa FITC-dextran flux responses to AICAR. Additionally, AICAR increased ERK1/2 phosphorylation, and inhibition of ERK1/2 by U0126, an ERK1/2 kinase inhibitor, or by siRNA decreased AICAR-induced TER responses. AICAR induced the serine S199 phosphorylation of claudin-4 and enhanced the interaction of claudin-4 and occludin. Furthermore, pretreatment with U0126 significantly suppressed AMPK-modulated phosphorylation, redistribution, and interaction with occludin of claudin-4. Taken together, these results indicated that claudin-4 played a crucial role in AMPK-modulated paracellular permeability and ERK1/2 was required in AMPK-modulated tight junction barrier function in submandibular gland.
Collapse
Affiliation(s)
- Ruo-Lan Xiang
- Center for Salivary Gland Diseases of Peking University School and Hospital of Stomatology, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
| | - Mei Mei
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Xin Cong
- Center for Salivary Gland Diseases of Peking University School and Hospital of Stomatology, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
| | - Jing Li
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Yan Zhang
- Center for Salivary Gland Diseases of Peking University School and Hospital of Stomatology, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
| | - Chong Ding
- Central Laboratory, Peking University School and Hospital of Stomatology, Beijing 100081, China
| | - Li-Ling Wu
- Center for Salivary Gland Diseases of Peking University School and Hospital of Stomatology, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University Health Science Center and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing 100191, China
| | - Guang-Yan Yu
- Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing 100081, China
| |
Collapse
|
236
|
Tamura A, Tsukita S. Paracellular barrier and channel functions of TJ claudins in organizing biological systems: Advances in the field of barriology revealed in knockout mice. Semin Cell Dev Biol 2014; 36:177-85. [DOI: 10.1016/j.semcdb.2014.09.019] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/15/2014] [Accepted: 09/17/2014] [Indexed: 02/06/2023]
|
237
|
Krug SM, Schulzke JD, Fromm M. Tight junction, selective permeability, and related diseases. Semin Cell Dev Biol 2014; 36:166-76. [DOI: 10.1016/j.semcdb.2014.09.002] [Citation(s) in RCA: 173] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 08/29/2014] [Accepted: 09/04/2014] [Indexed: 02/09/2023]
|
238
|
Affiliation(s)
- James L Boyer
- Department of Medicine and Liver Center, Yale University School of Medicine, New Haven, Connecticut.
| |
Collapse
|
239
|
Matsumoto K, Imasato M, Yamazaki Y, Tanaka H, Watanabe M, Eguchi H, Nagano H, Hikita H, Tatsumi T, Takehara T, Tamura A, Tsukita S. Claudin 2 deficiency reduces bile flow and increases susceptibility to cholesterol gallstone disease in mice. Gastroenterology 2014; 147:1134-45.e10. [PMID: 25068494 DOI: 10.1053/j.gastro.2014.07.033] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 07/10/2014] [Accepted: 07/19/2014] [Indexed: 01/09/2023]
Abstract
BACKGROUND & AIMS Bile formation and secretion are essential functions of the hepatobiliary system. Bile flow is generated by transepithelial transport of water and ionic/nonionic solutes via transcellular and paracellular pathways that is mainly driven by osmotic pressure. We examined the role of tight junction-based paracellular transport in bile secretion. Claudins are cell-cell adhesion molecules in tight junctions that create the paracellular barrier. The claudin family has 27 reported members, some of which have paracellular ion- and/or water-channel-like functions. Claudin 2 is a paracellular channel-forming protein that is highly expressed in hepatocytes and cholangiocytes; we examined the hepatobiliary system of claudin 2 knockout (Cldn2(-/-)) mice. METHODS We collected liver and biliary tissues from Cldn2(-/-) and Cldn2(+/+) mice and performed histologic, biochemical, and electrophysiologic analyses. We measured osmotic movement of water and/or ions in Cldn2(-/-) and Cldn2(+/+) hepatocytes and bile ducts. Mice were placed on lithogenic diets for 4 weeks and development of gallstone disease was assessed. RESULTS The rate of bile flow in Cldn2(-/-) mice was half that of Cldn2(+/+) mice, resulting in significantly more concentrated bile in livers of Cldn2(-/-) mice. Consistent with these findings, osmotic gradient-driven water flow was significantly reduced in hepatocyte bile canaliculi and bile ducts isolated from Cldn2(-/-) mice, compared with Cldn2(+/+) mice. After 4 weeks on lithogenic diets, all Cldn2(-/-) mice developed macroscopically visible gallstones; the main component of the gallstones was cholesterol (>98%). In contrast, none of the Cldn2(+/+) mice placed on lithogenic diets developed gallstones. CONCLUSIONS Based on studies of Cldn2(-/-) mice, claudin 2 regulates paracellular ion and water flow required for proper regulation of bile composition and flow. Dysregulation of this process increases susceptibility to cholesterol gallstone disease in mice.
Collapse
Affiliation(s)
- Kengo Matsumoto
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan; Department of Gastroenterology and Hepatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Mitsunobu Imasato
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Yuji Yamazaki
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hiroo Tanaka
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Mitsuhiro Watanabe
- Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan; Graduate School of Media and Governance, Faculty of Environment and Information Studies, Keio University, Kanagawa, Japan
| | - Hidetoshi Eguchi
- Department of Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hiroaki Nagano
- Department of Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hayato Hikita
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Tomohide Tatsumi
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Tetsuo Takehara
- Department of Gastroenterology and Hepatology, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Atsushi Tamura
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.
| | - Sachiko Tsukita
- Laboratory of Biological Science, Graduate School of Frontier Biosciences and Graduate School of Medicine, Osaka University, Osaka, Japan.
| |
Collapse
|
240
|
Abstract
BACKGROUND Mucosal abnormalities are potentially important in the primary pathogenesis of ulcerative colitis (UC). We investigated the mucosal transcriptomic expression profiles of biopsies from patients with UC and healthy controls, taken from macroscopically noninflamed tissue from the terminal ileum and 3 colonic locations with the objective of identifying abnormal molecules that might be involved in disease development. METHODS Whole-genome transcriptional analysis was performed on intestinal biopsies taken from 24 patients with UC, 26 healthy controls, and 14 patients with Crohn's disease. Differential gene expression analysis was performed at each tissue location separately, and results were then meta-analyzed. Significantly, differentially expressed genes were validated using quantitative polymerase chain reaction. The location of gene expression within the colon was determined using immunohistochemistry, subcellular fractionation, electron and confocal microscopy. DNA methylation was quantified by pyrosequencing. RESULTS Only 4 probes were abnormally expressed throughout the colon in patients with UC with Bone morphogenetic protein/Retinoic acid Inducible Neural-specific 3 (BRINP3) being the most significantly underexpressed. Attenuated expression of BRINP3 in UC was independent of current inflammation, unrelated to phenotype or treatment, and remained low at rebiopsy an average of 22 months later. BRINP3 is localized to the brush border of the colonic epithelium and expression is influenced by DNA methylation within its promoter. CONCLUSIONS Genome-wide expression analysis of noninflamed mucosal biopsies from patients with UC identified BRINP3 as significantly underexpressed throughout the colon in a large subset of patients with UC. Low levels of this gene could predispose or contribute to the maintenance of the characteristic mucosal inflammation seen in this condition.
Collapse
|
241
|
Abstract
The tight junction is an important subcellular organelle which plays a vital role in epithelial barrier function. Claudin, as the integral membrane component of tight junctions, creates a paracellular transport pathway for various ions to be reabsorbed by the kidneys. This review summarizes advances in claudin structure, function and pathophysiology in kidney diseases. Different claudin species confer selective paracellular permeability to each of three major renal tubular segments: the proximal tubule, the thick ascending limb of Henle’s loop and the distal nephron. Defects in claudin function can cause a wide spectrum of kidney diseases, such as hypomagnesemia, hypercalciuria, kidney stones and hypertension. Studies using transgenic mouse models with claudin mutations have recapitulated several of these renal disease phenotypes and have elucidated the underlying biological mechanisms. Modern recording approaches based upon scanning ion conductance microscopy may resolve the biophysical nature of claudin transport function and provide novel insight into tight junction architecture.
Collapse
Affiliation(s)
- Jianghui Hou
- Washington University Renal Division, St. Louis, MO 63110, USA
| |
Collapse
|
242
|
Pohl M, Shan Q, Petsch T, Styp-Rekowska B, Matthey P, Bleich M, Bachmann S, Theilig F. Short-term functional adaptation of aquaporin-1 surface expression in the proximal tubule, a component of glomerulotubular balance. J Am Soc Nephrol 2014; 26:1269-78. [PMID: 25270072 DOI: 10.1681/asn.2014020148] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 07/22/2014] [Indexed: 11/03/2022] Open
Abstract
Transepithelial water flow across the renal proximal tubule is mediated predominantly by aquaporin-1 (AQP1). Along this nephron segment, luminal delivery and transepithelial reabsorption are directly coupled, a phenomenon called glomerulotubular balance. We hypothesized that the surface expression of AQP1 is regulated by fluid shear stress, contributing to this effect. Consistent with this finding, we found that the abundance of AQP1 in brush border apical and basolateral membranes was augmented >2-fold by increasing luminal perfusion rates in isolated, microperfused proximal tubules for 15 minutes. Mouse kidneys with diminished endocytosis caused by a conditional deletion of megalin or the chloride channel ClC-5 had constitutively enhanced AQP1 abundance in the proximal tubule brush border membrane. In AQP1-transfected, cultured proximal tubule cells, fluid shear stress or the addition of cyclic nucleotides enhanced AQP1 surface expression and concomitantly diminished its ubiquitination. These effects were also associated with an elevated osmotic water permeability. In sum, we have shown that luminal surface expression of AQP1 in the proximal tubule brush border membrane is regulated in response to flow. Cellular trafficking, endocytosis, an intact endosomal compartment, and controlled protein stability are the likely prerequisites for AQP1 activation by enhanced tubular fluid shear stress, serving to maintain glomerulotubular balance.
Collapse
Affiliation(s)
- Marcus Pohl
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany
| | - Qixian Shan
- Institute of Physiology, Kiel University, Kiel, Germany
| | - Thomas Petsch
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany
| | | | - Patricia Matthey
- Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
| | - Markus Bleich
- Institute of Physiology, Kiel University, Kiel, Germany
| | | | - Franziska Theilig
- Institute of Anatomy, Charité Universitätsmedizin, Berlin, Germany; Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
| |
Collapse
|
243
|
García-Hernández V, Flores-Maldonado C, Rincon-Heredia R, Verdejo-Torres O, Bonilla-Delgado J, Meneses-Morales I, Gariglio P, Contreras RG. EGF Regulates Claudin-2 and -4 Expression Through Src and STAT3 in MDCK Cells. J Cell Physiol 2014; 230:105-15. [DOI: 10.1002/jcp.24687] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 05/22/2014] [Indexed: 12/20/2022]
Affiliation(s)
- Vicky García-Hernández
- Department of Physiology; Biophysics and Neurosciences; Center for Research and Advanced Studies (Cinvestav); México City México
| | - Catalina Flores-Maldonado
- Department of Physiology; Biophysics and Neurosciences; Center for Research and Advanced Studies (Cinvestav); México City México
| | - Ruth Rincon-Heredia
- Department of Physiology; Biophysics and Neurosciences; Center for Research and Advanced Studies (Cinvestav); México City México
- Department of Pharmacology; Center for Research and Advanced Studies (Cinvestav); México City México
| | - Odette Verdejo-Torres
- Department of Physiology; Biophysics and Neurosciences; Center for Research and Advanced Studies (Cinvestav); México City México
| | - José Bonilla-Delgado
- Laboratory of Genetics and Molecular Diagnosis; Research Unit; Hospital Juárez de México; México City México
| | - Ivan Meneses-Morales
- Breast Cancer investigation program; National Autonomous University of México (UNAM); México
- Department of Molecular Biology and Biotechnology; Biomedical Research Institute; National Autonomous University of México (UNAM); México
| | - Patricio Gariglio
- Department of Genetics and Molecular Biology; Center for Research and Advanced Studies (Cinvestav); México City México
| | - Rubén G. Contreras
- Department of Physiology; Biophysics and Neurosciences; Center for Research and Advanced Studies (Cinvestav); México City México
| |
Collapse
|
244
|
Goswami P, Das P, Verma AK, Prakash S, Das TK, Nag TC, Ahuja V, Gupta SD, Makharia GK. Are alterations of tight junctions at molecular and ultrastructural level different in duodenal biopsies of patients with celiac disease and Crohn's disease? Virchows Arch 2014; 465:521-30. [PMID: 25240724 DOI: 10.1007/s00428-014-1651-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/24/2014] [Accepted: 08/26/2014] [Indexed: 12/16/2022]
Abstract
Abnormalities of transmembrane and cytoplasmic proteins of tight junctions (TJ) have been implicated in pathogenesis of both celiac (CeD) and Crohn's diseases (CD). Since disease pathogenesis in CeD and CD are different, we planned to study if there is any differential expression pattern of TJ marker proteins and ultrastructural changes, respectively, in duodenal villi vs crypts. Endoscopic duodenal biopsies from treatment naïve patients with CeD (n = 24), active CD (n = 28), and functional dyspepsia (as controls, n = 15), both at baseline and 6 months after treatment, were subjected to light microscopic analysis (modified Marsh grading); immune-histochemical staining and Western blot analysis to see the expression of key TJ proteins [trans-membrane proteins (claudin-2, claudin-3, claudin-4, occludin, and JAM) and cytoplasmic protein (ZO-1)]. Transmission electron microscopy and image analysis of the TJs were also performed. There was significant overexpression of claudin-2 (pore-forming) and occludin (protein maintaining cell polarity) with under-expression of claudin-3 and claudin-4 (pore-sealing proteins) in treatment naïve CeD and active CD with simultaneous alteration in ultrastructure of TJs such as loss of penta-laminar structure and TJ dilatation. Normalization of some of these TJ proteins was noted 6 months after treatment. These changes were not disease specific and were not different in duodenal villi and crypts. Overexpression of pore-forming and under-expression of pore-sealing TJ proteins lead to dilatation of TJ. These changes are neither disease specific nor site specific and the end result of mucosal inflammation.
Collapse
Affiliation(s)
- Pooja Goswami
- Department of Gastroenterology and Human Nutrition, All India institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | | | | | | | | | | | | | | | | |
Collapse
|
245
|
Alexander RT, Rievaj J, Dimke H. Paracellular calcium transport across renal and intestinal epithelia. Biochem Cell Biol 2014; 92:467-80. [PMID: 25386841 DOI: 10.1139/bcb-2014-0061] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Calcium (Ca(2+)) is a key constituent in a myriad of physiological processes from intracellular signalling to the mineralization of bone. As a consequence, Ca(2+) is maintained within narrow limits when circulating in plasma. This is accomplished via regulated interplay between intestinal absorption, renal tubular reabsorption, and exchange with bone. Many studies have focused on the highly regulated active transcellular transport pathways for Ca(2+) from the duodenum of the intestine and the distal nephron of the kidney. However, comparatively little work has examined the molecular constituents creating the paracellular shunt across intestinal and renal epithelium, the transport pathway responsible for the majority of transepithelial Ca(2+) flux. More specifically, passive paracellular Ca(2+) absorption occurs across the majority of the intestine in addition to the renal proximal tubule and thick ascending limb of Henle's loop. Importantly, recent studies demonstrated that Ca(2+) transport through the paracellular shunt is significantly regulated. Therefore, we have summarized the evidence for different modes of paracellular Ca(2+) flux across renal and intestinal epithelia and highlighted recent molecular insights into both the mechanism of secondarily active paracellular Ca(2+) movement and the identity of claudins that permit the passage of Ca(2+) through the tight junction of these epithelia.
Collapse
Affiliation(s)
- R Todd Alexander
- a Department of Pediatrics, The University of Alberta, 4-585 Edmonton Clinic Health Academy, 11405 - 87 Ave, Edmonton, AB T6G 2R7, Canada
| | | | | |
Collapse
|
246
|
Tapia E, Sánchez-Lozada LG, García-Niño WR, García E, Cerecedo A, García-Arroyo FE, Osorio H, Arellano A, Cristóbal-García M, Loredo ML, Molina-Jijón E, Hernández-Damián J, Negrette-Guzmán M, Zazueta C, Huerta-Yepez S, Reyes JL, Madero M, Pedraza-Chaverrí J. Curcumin prevents maleate-induced nephrotoxicity: relation to hemodynamic alterations, oxidative stress, mitochondrial oxygen consumption and activity of respiratory complex I. Free Radic Res 2014; 48:1342-54. [PMID: 25119790 DOI: 10.3109/10715762.2014.954109] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The potential protective effect of the dietary antioxidant curcumin (120 mg/Kg/day for 6 days) against the renal injury induced by maleate was evaluated. Tubular proteinuria and oxidative stress were induced by a single injection of maleate (400 mg/kg) in rats. Maleate-induced renal injury included increase in renal vascular resistance and in the urinary excretion of total protein, glucose, sodium, neutrophil gelatinase-associated lipocalin (NGAL) and N-acetyl β-D-glucosaminidase (NAG), upregulation of kidney injury molecule (KIM)-1, decrease in renal blood flow and claudin-2 expression besides of necrosis and apoptosis of tubular cells on 24 h. Oxidative stress was determined by measuring the oxidation of lipids and proteins and diminution in renal Nrf2 levels. Studies were also conducted in renal epithelial LLC-PK1 cells and in mitochondria isolated from kidneys of all the experimental groups. Maleate induced cell damage and reactive oxygen species (ROS) production in LLC-PK1 cells in culture. In addition, maleate treatment reduced oxygen consumption in ADP-stimulated mitochondria and diminished respiratory control index when using malate/glutamate as substrate. The activities of both complex I and aconitase were also diminished. All the above-described alterations were prevented by curcumin. It is concluded that curcumin is able to attenuate in vivo maleate-induced nephropathy and in vitro cell damage. The in vivo protection was associated to the prevention of oxidative stress and preservation of mitochondrial oxygen consumption and activity of respiratory complex I, and the in vitro protection was associated to the prevention of ROS production.
Collapse
Affiliation(s)
- E Tapia
- Department of Nephrology, National Institute of Cardiology I. Ch. , Mexico City , Mexico
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
247
|
Wilmes A, Aschauer L, Limonciel A, Pfaller W, Jennings P. Evidence for a role of claudin 2 as a proximal tubular stress responsive paracellular water channel. Toxicol Appl Pharmacol 2014; 279:163-72. [DOI: 10.1016/j.taap.2014.05.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 05/16/2014] [Accepted: 05/27/2014] [Indexed: 01/04/2023]
|
248
|
Trujillo J, Molina-Jijón E, Medina-Campos ON, Rodríguez-Muñoz R, Reyes JL, Loredo ML, Tapia E, Sánchez-Lozada LG, Barrera-Oviedo D, Pedraza-Chaverri J. Renal tight junction proteins are decreased in cisplatin-induced nephrotoxicity in rats. Toxicol Mech Methods 2014; 24:520-8. [PMID: 25052570 DOI: 10.3109/15376516.2014.948248] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
UNLABELLED Cisplatin (CP) is an antineoplastic agent that induces nephrotoxicity and oxidative stress. It is unknown whether renal tight junction (TJ) proteins expression and localization are modified in CP-induced nephrotoxicity. OBJECTIVE To study if the expression of the TJ proteins occludin, claudin-2, claudin-5 and zonula occludens-1 (ZO-1) is modified in rats with CP-induced nephrotoxicity. MATERIALS AND METHODS Male Wistar rats (n = 5/group) were injected with saline solution (V group), and the other group (CP group) was injected with a single dose of saline solution and CP (7.5 mg/kg i.p.). Rats were sacrificed 72 h after CP injection and blood, and 24-h urine samples were collected. Several plasma and urinary injury biomarkers as well as renal histopathology lesions, oxidative and nitrosative stress markers were evaluated, and protein levels of ocludin, claudin-2, claudin-5, ZO-1 were measured by Western blot. Statistically significant changes noted with different p < 0.05 versus V. RESULTS Nephrotoxicity was evident by histological alterations, glycosuria, decrease in creatinine clearance, increase in fractional excretion of sodium, serum creatinine and kidney injury molecule-1. These changes were associated with oxidative/nitrosative stress (increased renal abundance of 3-nitrotyrosine and protein kinase Cβ2 and decreased renal expression of nuclear factor-erythroid-2-related factor 2) and decreased activity of antioxidant enzymes. Finally, it was found that CP-induced renal damage was associated with decreased renal expression of occludin and claudin-2. DISCUSSION AND CONCLUSION CP altered the TJ proteins expression and localization in the proximal tubule that was associated with oxidative/nitrosative stress.
Collapse
Affiliation(s)
- Joyce Trujillo
- Department of Biology, Faculty of Chemistry, National Autonomous University of Mexico (UNAM) , University City, Mexico D.F. , Mexico
| | | | | | | | | | | | | | | | | | | |
Collapse
|
249
|
Weijenborg PW, Smout AJPM, Verseijden C, van Veen HA, Verheij J, de Jonge WJ, Bredenoord AJ. Hypersensitivity to acid is associated with impaired esophageal mucosal integrity in patients with gastroesophageal reflux disease with and without esophagitis. Am J Physiol Gastrointest Liver Physiol 2014; 307:G323-9. [PMID: 24924748 DOI: 10.1152/ajpgi.00345.2013] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Increased esophageal sensitivity and impaired mucosal integrity have both been described in patients with gastroesophageal reflux disease, but the relationship between hypersensitivity and mucosal integrity is unclear. The aim of the present study was to investigate acid sensitivity in patients with erosive and nonerosive reflux disease and control subjects to determine the relation with functional esophageal mucosal integrity changes as well as to investigate cellular mechanisms of impaired mucosal integrity in these patients. In this prospective experimental study, 12 patients with nonerosive reflux disease, 12 patients with esophagitis grade A or B, and 11 healthy control subjects underwent an acid perfusion test and upper endoscopy. Mucosal integrity was measured during endoscopy by electrical tissue impedance spectroscopy and biopsy specimens were analyzed in Ussing chambers for transepithelial electrical resistance, transepithelial permeability and gene expression of tight junction proteins and filaggrin. Patients with nonerosive reflux disease and esophagitis were more sensitive to acid perfusion compared with control subjects, having a shorter time to perception of heartburn and higher perceived intensity of heartburn. In reflux patients, enhanced acid sensitivity was associated with impairment of in vivo and vitro esophageal mucosal integrity. Mucosal integrity was significantly impaired in patients with esophagitis, displaying higher transepithelial permeability and lower extracellular impedance. Although no significant differences in the expression of tight junction proteins were found in biopsies among patient groups, mucosal integrity parameters in reflux patients correlated negatively with the expression of filaggrin. In conclusion, sensitivity to acid is enhanced in patients with gastroesophageal reflux disease, irrespective of the presence of erosions, and is associated with impaired esophageal mucosal integrity. Mucosal integrity of the esophagus is associated with the expression of filaggrin.
Collapse
Affiliation(s)
- Pim W Weijenborg
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - André J P M Smout
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
| | - Caroline Verseijden
- Tytgat Institute for Liver and Intestinal Research, Amsterdam, The Netherlands
| | - Henk A van Veen
- Van Leeuwenhoek Center for Advanced Microscopy, Department of Cell Biology, Academic Medical Center, Amsterdam, The Netherlands; and
| | - Joanne Verheij
- Department of Pathology, Academic Medical Center, Amsterdam, The Netherlands
| | - Wouter J de Jonge
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands; Tytgat Institute for Liver and Intestinal Research, Amsterdam, The Netherlands
| | - Albert J Bredenoord
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands;
| |
Collapse
|
250
|
Molina-Jijón E, Rodríguez-Muñoz R, Namorado MDC, Pedraza-Chaverri J, Reyes JL. Oxidative stress induces claudin-2 nitration in experimental type 1 diabetic nephropathy. Free Radic Biol Med 2014; 72:162-75. [PMID: 24726862 DOI: 10.1016/j.freeradbiomed.2014.03.040] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 03/13/2014] [Accepted: 03/29/2014] [Indexed: 02/07/2023]
Abstract
Renal complications in diabetes are severe and may lead to renal insufficiency. Early alterations in tight junction (TJ) proteins in diabetic nephropathy (DN) have not been explored and the role of oxidative stress in their disassembly has been poorly characterized. We investigated the expression and distribution of TJ proteins: claudin-5 in glomeruli (GL), occludin and claudin-2 in proximal tubules (PTs), and ZO-1 and claudin-1, -4, and -8 in distal tubules (DTs) of rats 21 days after streptozotocin injection. Redox status along the nephron segments was evaluated. Diabetes increased kidney injury molecule-1 expression. Expression of sodium glucose cotransporters (SGLT1 and SGLT2) and facilitative glucose transporter (GLUT2) was induced. Increased oxidative stress was present in GL and PTs and to a lesser extent in DTs (measured by superoxide production and PKCβ2 expression), owing to NADPH oxidase activation and uncoupling of the endothelial nitric oxide synthase-dependent pathway. Claudin-5, occludin, and claudin-2 expression was decreased, whereas claudin-4 and -8 expression increased. ZO-1 was redistributed from membrane to cytosol. Increased nitration of tyrosine residues in claudin-2 was found, which might contribute to decrement of this protein in proximal tubule. In contrast, occludin was not nitrated. We suggest that loss of claudin-2 is associated with increased natriuresis and that loss of glomerular claudin-5 might explain early presence of proteinuria. These findings suggest that oxidative stress is related to alterations in TJ proteins in the kidney that are relevant to the pathogenesis and progression of DN and for altered sodium regulation in diabetes.
Collapse
Affiliation(s)
- Eduardo Molina-Jijón
- Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, México, DF 07360, Mexico
| | - Rafael Rodríguez-Muñoz
- Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, México, DF 07360, Mexico
| | - María del Carmen Namorado
- Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, México, DF 07360, Mexico
| | - José Pedraza-Chaverri
- Department of Biology, Faculty of Chemistry, National Autonomous University of Mexico, 04510 University City, DF, Mexico
| | - José L Reyes
- Department of Physiology, Biophysics, and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, México, DF 07360, Mexico.
| |
Collapse
|