1
|
Merlen G, Tordjmann T. Tight junction proteins and biliary diseases. Curr Opin Gastroenterol 2024; 40:70-76. [PMID: 38260939 DOI: 10.1097/mog.0000000000000996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
PURPOSE OF REVIEW In the pathophysiological context of cholangiopathies and more broadly of hepatopathies, while it is conceptually clear that the maintenance of inter-cholangiocyte and inter-hepatocyte tight junction integrity would be crucial for liver protection, only scarce studies have been devoted to this topic. Indeed, in the liver, alteration of tight junctions, the intercellular adhesion complexes that control paracellular permeability would result in leaky bile ducts and bile canaliculi, allowing bile reflux towards hepatic parenchyma, contributing to injury during the disease process. RECENT FINDINGS Last decades have provided a great deal of information regarding both tight junction structural organization and signaling pathways related to tight junctions, providing clues about potential intervention to modulate paracellular permeability during cholangiopathies pathogenesis. Interestingly, several liver diseases have been reported to be associated with abnormal expression of one or several tight junction proteins. However, the question remains unanswered if these alterations would be primarily involved in the disease pathogenesis or if they would occur secondarily in the pathological course. SUMMARY In this review, we provide an overview of tight junction disruptions described in various biliary diseases that should pave the way for defining new therapeutic targets in this field.
Collapse
Affiliation(s)
- Grégory Merlen
- INSERM U1193, Université Paris-Saclay, bât Henri Moissan, 17 av. des Sciences, Orsay, France
| | | |
Collapse
|
2
|
Yadav R, Kumar Y, Dahiya D, Bhatia A. Claudins: The Newly Emerging Targets in Breast Cancer. Clin Breast Cancer 2022; 22:737-752. [PMID: 36175290 DOI: 10.1016/j.clbc.2022.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 09/04/2022] [Indexed: 01/25/2023]
Abstract
Claudin-low breast cancers are recently described entities showing low expression of certain claudins and cell adhesion molecules. Claudins constitute the backbone of tight junctions (TJs) formed between 2 cells. Their dysregulation plays a vital role in tumorigenesis. First part of the article focuses on the role of claudins in the TJ organization, their structural-functional characteristics, and post-transcriptional and translational modifications. The latter part of the review attempts to summarize existing knowledge regarding the status of claudins in breast cancer. The article also provides an overview of the effect of claudins on tumor progression, metastasis, stemness, chemotherapy resistance, and their crosstalk with relevant signaling pathways in breast cancer. Claudins can act as 2-edged swords in tumors. Some claudins have either tumor-suppressive/ promoting action, while others work as both in a context-dependent manner. Claudins regulate many important events in breast cancer. However, the intricacies involved in their activity are poorly understood. Post-translational modifications in claudins and their impact on TJ integrity, function, and tumor behavior are still unclear. Although their role in adverse events in breast cancer is recognized, their potential to serve as relevant targets for future therapeutics, especially for difficult-to-treat subtypes of the above malignancy, remains to be explored.
Collapse
Affiliation(s)
- Reena Yadav
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Yashwant Kumar
- Department of Immunopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Divya Dahiya
- Department of General Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Alka Bhatia
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
| |
Collapse
|
3
|
Berselli A, Benfenati F, Maragliano L, Alberini G. Multiscale modelling of claudin-based assemblies: a magnifying glass for novel structures of biological interfaces. Comput Struct Biotechnol J 2022; 20:5984-6010. [DOI: 10.1016/j.csbj.2022.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 11/03/2022] Open
|
4
|
Barbara G, Barbaro MR, Fuschi D, Palombo M, Falangone F, Cremon C, Marasco G, Stanghellini V. Corrigendum: Inflammatory and Microbiota-Related Regulation of the Intestinal Epithelial Barrier. Front Nutr 2021; 8:790387. [PMID: 34790692 PMCID: PMC8591313 DOI: 10.3389/fnut.2021.790387] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 12/18/2022] Open
Affiliation(s)
- Giovanni Barbara
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Maria Raffaella Barbaro
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Daniele Fuschi
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Marta Palombo
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Francesca Falangone
- Medical-Surgical Department of Clinical Sciences and Translational Medicine, University Sapienza, Rome, Italy
| | - Cesare Cremon
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Giovanni Marasco
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Vincenzo Stanghellini
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| |
Collapse
|
5
|
Barbara G, Barbaro MR, Fuschi D, Palombo M, Falangone F, Cremon C, Marasco G, Stanghellini V. Inflammatory and Microbiota-Related Regulation of the Intestinal Epithelial Barrier. Front Nutr 2021; 8:718356. [PMID: 34589512 PMCID: PMC8475765 DOI: 10.3389/fnut.2021.718356] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/12/2021] [Indexed: 12/19/2022] Open
Abstract
The intestinal epithelial barrier (IEB) is one of the largest interfaces between the environment and the internal milieu of the body. It is essential to limit the passage of harmful antigens and microorganisms and, on the other side, to assure the absorption of nutrients and water. The maintenance of this delicate equilibrium is tightly regulated as it is essential for human homeostasis. Luminal solutes and ions can pass across the IEB via two main routes: the transcellular pathway or the paracellular pathway. Tight junctions (TJs) are a multi-protein complex responsible for the regulation of paracellular permeability. TJs control the passage of antigens through the IEB and have a key role in maintaining barrier integrity. Several factors, including cytokines, gut microbiota, and dietary components are known to regulate intestinal TJs. Gut microbiota participates in several human functions including the modulation of epithelial cells and immune system through the release of several metabolites, such as short-chain fatty acids (SCFAs). Mediators released by immune cells can induce epithelial cell damage and TJs dysfunction. The subsequent disruption of the IEB allows the passage of antigens into the mucosa leading to further inflammation. Growing evidence indicates that dysbiosis, immune activation, and IEB dysfunction have a role in several diseases, including irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and gluten-related conditions. Here we summarize the interplay between the IEB and gut microbiota and mucosal immune system and their involvement in IBS, IBD, and gluten-related disorders.
Collapse
Affiliation(s)
- Giovanni Barbara
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Maria Raffaella Barbaro
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Daniele Fuschi
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Marta Palombo
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Francesca Falangone
- Medical-Surgical Department of Clinical Sciences and Translational Medicine, University Sapienza, Rome, Italy
| | - Cesare Cremon
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Giovanni Marasco
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Vincenzo Stanghellini
- IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.,Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| |
Collapse
|
6
|
Abstract
Cholesterol gallstone disease (CGD) affects 10-15% of the adult population worldwide and the prevalence increases as a result of longer life expectancy as well as rising obesity in the general population. Beside well established CGD risk factors including environmental and genetic determinants (LITH genes), a correlation between thyroid dysfunction and CGD has been suggested in several human and murine studies. Although the precise underlying mechanisms are poorly understood, thyroid hormones may impact bile flow, bile composition and the maintenance of the enterohepatic circulation. Further there is evidence that thyroid hormones possibly impact LITH genes which are regulated by nuclear receptors (NRs). A better understanding of the CGD pathomechanisms might contribute to personalized prevention and therapy of highly prevalent and economically significant digestive disease. This review presents the current knowledge about the association between CGD and thyroid hormone dysfunction.
Collapse
Affiliation(s)
- Irina Kube
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany
| | - Denise Zwanziger
- Department of Endocrinology, Diabetes and Metabolism, University of Duisburg-Essen, Essen, Germany
| |
Collapse
|
7
|
Seker M, Fernández-Rodríguez C, Martínez-Cruz LA, Müller D. Mouse Models of Human Claudin-Associated Disorders: Benefits and Limitations. Int J Mol Sci 2019; 20:ijms20215504. [PMID: 31694170 PMCID: PMC6862546 DOI: 10.3390/ijms20215504] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/01/2019] [Accepted: 11/02/2019] [Indexed: 12/16/2022] Open
Abstract
In higher organisms, epithelia separate compartments in order to guarantee their proper function. Such structures are able to seal but also to allow substances to pass. Within the paracellular pathway, a supramolecular structure, the tight junction transport is largely controlled by the temporospatial regulation of its major protein family called claudins. Besides the fact that the expression of claudins has been identified in different forms of human diseases like cancer, clearly defined mutations in the corresponding claudin genes have been shown to cause distinct human disorders. Such disorders comprise the skin and its adjacent structures, liver, kidney, the inner ear, and the eye. From the phenotype analysis, it has also become clear that different claudins can cause a complex phenotype when expressed in different organs. To gain deeper insights into the physiology and pathophysiology of claudin-associated disorders, several mouse models have been generated. In order to model human disorders in detail, they have been designed either as full knockouts, knock-downs or knock-ins by a variety of techniques. Here, we review human disorders caused by CLDN mutations and their corresponding mouse models that have been generated thus far and assess their usefulness as a model for the corresponding human disorder.
Collapse
Affiliation(s)
- Murat Seker
- Department of Pediatric Gastroenterology, Nephrology and Metabolism, Charité—Universitätsmedizin Berlin, Charité, 13353 Berlin, Germany;
| | | | | | - Dominik Müller
- Department of Pediatric Gastroenterology, Nephrology and Metabolism, Charité—Universitätsmedizin Berlin, Charité, 13353 Berlin, Germany;
- Correspondence:
| |
Collapse
|
8
|
Abstract
Our bodies are protected from the external environment by mucosal barriers that are lined by epithelial cells. The epithelium plays a critical role as a highly dynamic, selective semipermeable barrier that separates luminal contents and pathogens from the rest of the body and controlling the absorption of nutrients, fluid and solutes. A series of protein complexes including the adherens junction, desmosomes, and tight junctions function as the principal barrier in paracellular diffusion and regulators of intracellular solute, protein, and lipid transport. Tight junctions are composed of a series of proteins called occludins, junctional adhesion molecules, and claudins that reside primarily as the most apical intercellular junction. Here we will review one of these protein families, claudins, and their relevance to gastrointestinal and liver diseases.
Collapse
|
9
|
Hermiz SJ, Diegidio P, Garimella R, Ortiz-Pujols S, Yu H, Isaacson A, Mauro MA, Cairns BA, Hultman CS. Acalculous Cholecystitis in Burn Patients: Is There a Role for Percutaneous Cholecystostomy? Clin Plast Surg 2017; 44:567-571. [PMID: 28576245 DOI: 10.1016/j.cps.2017.02.025] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Although acute acalculous cholecystitis is uncommon in burn patients, this condition can be rapidly fatal due to delays in diagnosis and treatment and should always be considered in the differential diagnosis when burn patients become septic, develop abdominal pain, or have hemodynamic instability. This article reviews the use of percutaneous cholecystostomy in burn patients as both a diagnostic and therapeutic intervention.
Collapse
Affiliation(s)
- Steven J Hermiz
- Department of Surgery, University of South Carolina School of Medicine, Columbia, SC 29209, USA
| | - Paul Diegidio
- Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Roja Garimella
- Alpert Medical School, Brown University, Providence, RI 02903, USA
| | - Shiara Ortiz-Pujols
- Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Hyeon Yu
- Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Ari Isaacson
- Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Matthew A Mauro
- Department of Radiology, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Bruce A Cairns
- Department of Surgery, University of North Carolina School of Medicine, Chapel Hill, NC 27599, USA
| | - Charles Scott Hultman
- Division of Plastic Surgery, Department of Surgery, University of North Carolina School of Medicine, Suite 7038, Burnett Womack, CB#7195, Chapel Hill, NC 27599, USA.
| |
Collapse
|
10
|
Zwanziger D, Rakov H, Engels K, Moeller LC, Führer D. Sex-Dependent Claudin-1 Expression in the Liver of Euthyroid and Hypothyroid Mice. Eur Thyroid J 2015; 4:67-73. [PMID: 26601075 PMCID: PMC4640300 DOI: 10.1159/000431316] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 05/11/2015] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND In the liver the tight junction protein claudin-1 plays an important role in bile secretion by maintaining the paracellular barrier of bile canaliculi and the bile duct. A diminished bile excretion has been found in hypothyroid patients, and the prevalence of gallstones is increased in hypothyroidism. This association, however, only applies for men and is in contrast to the well-established female preponderance of biliary disease in the general population. OBJECTIVES We hypothesized that hypothyroidism could lead to altered claudin-1 expression in the liver, and that this effect may be sex specific. METHODS We characterized claudin-1 expression and localization in livers of euthyroid and hypothyroid male and female C57BL/6NTac mice by real-time PCR, Western blot and immunofluorescence. RESULTS Claudin-1 is expressed in canalicular regions and the bile ducts of the murine liver. Livers of female mice showed lower claudin-1 expression than male livers. In hypothyroid livers, female animals showed an elevated claudin-1 expression, whereas reduced claudin-1 expression was found in male animals compared to the euthyroid controls. CONCLUSION We demonstrate a correlation between claudin-1 expression and hypothyroidism in the murine liver. Furthermore, a sex-dependent alteration of claudin-1 expression was found.
Collapse
Affiliation(s)
- Denise Zwanziger
- *Denise Zwanziger, PhD, Department of Endocrinology and Metabolism and Division of Laboratory Research, University Hospital Essen, Hufelandstrasse 55, DE-45147 Essen (Germany), E-Mail
| | | | | | | | | |
Collapse
|
11
|
Rao RK, Samak G. Bile duct epithelial tight junctions and barrier function. Tissue Barriers 2013; 1:e25718. [PMID: 24665411 PMCID: PMC3783222 DOI: 10.4161/tisb.25718] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/07/2013] [Accepted: 07/10/2013] [Indexed: 01/15/2023] Open
Abstract
Bile ducts play a crucial role in the formation and secretion of bile as well as excretion of circulating xenobiotic substances. In addition to its secretory and excretory functions, bile duct epithelium plays an important role in the formation of a barrier to the diffusion of toxic substances from bile into the hepatic interstitial tissue. Disruption of barrier function and toxic injury to liver cells appear to be involved in the pathogenesis of a variety of liver diseases such as primary sclerosing cholangitis, primary biliary cirrhosis and cholangiocarcinoma. Although the investigations into understanding the structure and regulation of tight junctions in gut, renal and endothelial tissues have expanded rapidly, very little is known about the structure and regulation of tight junctions in the bile duct epithelium. In this article we summarize the current understanding of physiology and pathophysiology of bile duct epithelium, the structure and regulation of tight junctions in canaliculi and bile duct epithelia and different mechanisms involved in the regulation of disruption and protection of bile duct epithelial tight junctions. This article will make a case for the need of future investigations toward our understanding of molecular organization and regulation of canalicular and bile duct epithelial tight junctions.
Collapse
Affiliation(s)
- R K Rao
- Department of Physiology; University of Tennessee Health Science Center; Memphis, TN USA
| | - G Samak
- Department of Zoology; D.V.S. College; Shimoga, India
| |
Collapse
|
12
|
Holczbauer Á, Gyöngyösi B, Lotz G, Szijártó A, Kupcsulik P, Schaff Z, Kiss A. Distinct claudin expression profiles of hepatocellular carcinoma and metastatic colorectal and pancreatic carcinomas. J Histochem Cytochem 2013; 61:294-305. [PMID: 23385421 PMCID: PMC3636686 DOI: 10.1369/0022155413479123] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Tight junction proteins, including claudins, are often dysregulated during carcinogenesis and tumor progression. Moreover, the claudin expression pattern usually varies between different tumor entities. We aimed to investigate claudin expression profiles of primary and metastatic liver malignancies. We analyzed claudin-1, -2, -3, -4, and -7 expression by quantitative immunohistochemistry and real-time RT-PCR, respectively. Twenty hepatocellular carcinomas (HCCs) and liver metastases of 20 colorectal adenocarcinomas (CRLMs) and 15 pancreatic adenocarcinomas (PLMs) were studied together with paired surrounding non-tumorous liver samples and 5 normal liver samples. Strong claudin-3 and -7 immunohistochemical positivities were detected in CRLM samples, each with significantly stronger staining when compared with HCC and PLM groups. Claudin-1 protein was found highly expressed in CRLM, in contrast to lower expression in PLM and HCC. CRLMs and PLMs also were strongly positive for claudin-4, while being virtually undetectable in HCC. Claudin-2 showed strong positivity in non-tumorous liver tissue, whereas significantly weaker positivity was observed in all tumors. Differences in mRNA expression were mostly similar to those found by immunohistochemistry. In conclusion, HCC and both CRLM and PLM display distinct claudin expression profiles, which might provide better understanding of the pathobiology of these lesions and might be used for differential diagnosis.
Collapse
Affiliation(s)
- Ágnes Holczbauer
- 2nd Department of Pathology, Semmelweis University, Budapest, Hungary
| | | | | | | | | | | | | |
Collapse
|
13
|
Abstract
Claudins are tight junction membrane proteins that are expressed in epithelia and endothelia and form paracellular barriers and pores that determine tight junction permeability. This review summarizes our current knowledge of this large protein family and discusses recent advances in our understanding of their structure and physiological functions.
Collapse
Affiliation(s)
- Dorothee Günzel
- Department of Clinical Physiology, Charité, Campus Benjamin Franklin, Berlin, Germany
| | | |
Collapse
|
14
|
Hsu LW, Ho YC, Chuang EY, Chen CT, Juang JH, Su FY, Hwang SM, Sung HW. Effects of pH on molecular mechanisms of chitosan–integrin interactions and resulting tight-junction disruptions. Biomaterials 2013; 34:784-93. [DOI: 10.1016/j.biomaterials.2012.09.082] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 09/30/2012] [Indexed: 11/28/2022]
|
15
|
Expressions of Cell Junction Regulatory Proteins and Their Association With Clinicopathologic Parameters in Benign and Malignant Gallbladder Lesions. Am J Med Sci 2011; 342:388-94. [DOI: 10.1097/maj.0b013e31821e12af] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
16
|
Yu ASL, Cheng MH, Coalson RD. Calcium inhibits paracellular sodium conductance through claudin-2 by competitive binding. J Biol Chem 2010; 285:37060-9. [PMID: 20807759 DOI: 10.1074/jbc.m110.146621] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Claudins form paracellular pores at the tight junction in epithelial cells. Profound depletion of extracellular calcium is well known to cause loosening of the tight junction with loss of transepithelial resistance. However, moderate variations in calcium concentrations within the physiological range can also regulate transepithelial permeability. To investigate the underlying molecular mechanisms, we studied the effects of calcium on the permeability of claudin-2, expressed in an inducible MDCK I cell line. We found that in the physiological range, calcium acts as a reversible inhibitor of the total conductance and Na(+) permeability of claudin-2, without causing changes in tight junction structure. The effect of calcium is enhanced at low Na(+) concentrations, consistent with a competitive effect. Furthermore, mutation of an intrapore negatively charged binding site, Asp-65, to asparagine partially abrogated the inhibitory effect of calcium. This suggests that calcium competes with Na(+) for binding to Asp-65. Other polyvalent cations had similar effects, including La(3+), which caused severe and irreversible inhibition of conductance. Brownian dynamics simulations demonstrated that such inhibition can be explained if Asp-65 has a relatively high charge density, thus favoring binding of Ca(2+) over that of Na(+), reducing Ca(2+) permeation by inhibiting its dissociation from this site, and decreasing Na(+) conductance through repulsive electrostatic interaction with Ca(2+). These findings may explain why hypercalcemia inhibits Na(+) reabsorption in the proximal tubule of the kidney.
Collapse
Affiliation(s)
- Alan S L Yu
- Division of Nephrology, Department of Medicine, University of Southern California Keck School of Medicine, Los Angeles, California 90089, USA.
| | | | | |
Collapse
|
17
|
Németh Z, Szász AM, Somorácz A, Tátrai P, Németh J, Gyorffy H, Szíjártó A, Kupcsulik P, Kiss A, Schaff Z. Zonula occludens-1, occludin, and E-cadherin protein expression in biliary tract cancers. Pathol Oncol Res 2010; 15:533-9. [PMID: 19184677 DOI: 10.1007/s12253-009-9150-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Accepted: 01/08/2009] [Indexed: 02/06/2023]
Abstract
The incidence of cholangiocarcinomas originating from intrahepatic and extrahepatic bile ducts, as well as of gallbladder carcinoma is increasing worldwide. The malignant transformation of biliary epithelia involves profound alterations of proteins in the intercellular junctions, among others zonula occludens-1 (ZO-1), occludin, and E-cadherin. Each plays important role in the maintenance of epithelial cell polarity and regulation of cell growth and differentiation. Our aim was to investigate ZO-1, occludin, and E-cadherin immunohistochemical reactions in tissue microarray blocks containing 57 normal and 62 neoplastic biliary tract samples. We demonstrated that the tight junction components ZO-1, occludin, and E-cadherin are downregulated in carcinomas arising from various compartments of the biliary tract (normal intrahepatic and extrahepatic bile ducts, gallbladder) as compared with their normal sites of origin. These results were confirmed by discriminant analysis yielding clear separation of the three normal sample groups from carcinomas in the corresponding locations.
Collapse
Affiliation(s)
- Zsuzsanna Németh
- 2nd Department of Pathology, Semmelweis University, Ulloi út 93, H-1091 Budapest, Hungary
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Koskela M, Gäddnäs F, Ala-Kokko TI, Laurila JJ, Saarnio J, Oikarinen A, Koivukangas V. Epidermal wound healing in severe sepsis and septic shock in humans. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2009; 13:R100. [PMID: 19552820 PMCID: PMC2717472 DOI: 10.1186/cc7932] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 02/17/2009] [Accepted: 06/24/2009] [Indexed: 12/30/2022]
Abstract
Introduction The effect of sepsis on epidermal wound healing has not been previously studied. It was hypothesised that epidermal wound healing is disturbed in severe sepsis. Methods Blister wounds were induced in 35 patients with severe sepsis and in 15 healthy controls. The healing of the wounds was followed up by measuring transepidermal water loss and blood flow in the wound, reflecting the restoration of the epidermal barrier function and inflammation, respectively. The first set of suction blisters (early wound) was made within 48 hours of the first sepsis-induced organ failure and the second set (late wound) four days after the first wound. In addition, measurements were made on the intact skin. Results The average age of the whole study population was 62 years (standard deviation [SD] 12). The mean Acute Physiology and Chronic Health Evaluation II (APACHE II) score on admission was 25 (SD 8). The two most common causes of infections were peritonitis and pneumonia. Sixty-six percent of the patients developed multiple organ failure. The decrease in water evaporation from the wound during the first four days was lower in septic patients than in the control subjects (56 g/m2 per hour versus 124 g/m2 per hour, P = 0.004). On the fourth day, septic patients had significantly higher blood flow in the wound compared with the control subjects (septic patients 110 units versus control subjects 47 units, P = 0.001). No difference in transepidermal water loss from the intact skin was found between septic patients and controls. Septic patients had higher blood flow in the intact skin on the fourth and on the eighth day of study compared with the controls. Conclusions The restoration of the epidermal barrier function is delayed and wound blood flow is increased in patients with severe sepsis.
Collapse
Affiliation(s)
- Marjo Koskela
- Department of Anesthesiology, Division of Intensive Care Medicine, Oulu University Hospital, 90029 OUH, Finland.
| | | | | | | | | | | | | |
Collapse
|
19
|
Chasiotis H, Kelly SP. Occludin and hydromineral balance in Xenopus laevis. ACTA ACUST UNITED AC 2009; 212:287-96. [PMID: 19112148 DOI: 10.1242/jeb.022822] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
To investigate the response of the tight junction (TJ) protein occludin to environmental change in an anuran amphibian, we examined occludin tissue distribution, immunolocalization and alterations in mRNA expression in African clawed frogs (Xenopus laevis) acclimated to brackish water (BW) conditions (from freshwater to 2 per thousand, 5 per thousand or 10 per thousand salt water). Occludin mRNA is widely expressed in Xenopus and is abundant in tissues involved in regulating salt and water balance, such as the gastrointestinal (GI) tract, kidney and urinary bladder. Immunohistochemical analyses revealed strong occludin immunolabelling in the apicolateral region of epithelia lining the GI tract and mRNA expression increased along the longitudinal axis of the gut. In kidney tissue, occludin was differentially expressed on the luminal side of the nephron tubule, appearing in the distal tubules and collecting ducts only. In response to BW acclimation, Xenopus exhibited a significant loss of tissue water as well as salinity-dependent elevations in serum osmolality as a result of increased urea levels followed by elevated serum Na(+) and Cl(-) levels. Tissue-specific alterations in the ionomotive enzyme Na(+),K(+)-ATPase were also observed in Xenopus in response to BW acclimation. Most notably, Na(+),K(+)-ATPase activity in the rectum increased in response to elevated environmental salt concentrations while renal activity decreased. Furthermore, acclimation to BW caused tissue-specific and salinity-dependent alterations in occludin mRNA expression within select Xenopus osmoregulatory organs. Taken together, these studies suggest that alterations in occludin, in conjunction with active transport processes, may contribute to amphibian hydromineral homeostasis during environmental change.
Collapse
Affiliation(s)
- Helen Chasiotis
- Department of Biology, York University, Toronto, Ontario, Canada M3J 1P3.
| | | |
Collapse
|
20
|
Németh Z, Szász AM, Tátrai P, Németh J, Gyorffy H, Somorácz A, Szíjártó A, Kupcsulik P, Kiss A, Schaff Z. Claudin-1, -2, -3, -4, -7, -8, and -10 protein expression in biliary tract cancers. J Histochem Cytochem 2008; 57:113-21. [PMID: 18854598 DOI: 10.1369/jhc.2008.952291] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Biliary tract cancers are relatively common malignant gastrointestinal tumors in the elderly. Claudins are integral components of tight junctions that play important roles in maintaining epithelial cell polarity, controlling paracellular diffusion, and regulating cell growth and differentiation. The expression profile of claudins has been extensively characterized, but few reports exist on their expression in the normal and neoplastic biliary tract. Our aim was therefore to study claudins by IHC reactions in normal and neoplastic biliary tract samples. We detected that claudin expressions differ in the normal sample groups: the normal gallbladder strongly expressed claudin-2, -3, -4, and -10, but only weak reactions were seen in normal intrahepatic bile ducts. Although each cancer type expressed several claudins with various intensities, only claudin-4 presented especially strong immunoreactions in extrahepatic bile duct cancers and gallbladder carcinomas, whereas claudin-1 and -10 presented in intrahepatic bile duct cancers. Comparing the normal and carcinoma groups, the most significant decrease was detected in the expression of claudin-10. In conclusion, the expression pattern of claudins is different in the various parts of the normal and neoplastic biliary tract; moreover, an unequivocal decrease was detected in the carcinomas compared with their corresponding normal samples. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.
Collapse
Affiliation(s)
- Zsuzsanna Németh
- 2nd Department of Pathology, Semmelweis University, Budapest, Hungary
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Leveau P, Andersson E, Carlgren I, Willner J, Andersson R. Percutaneous cholecystostomy: a bridge to surgery or definite management of acute cholecystitis in high-risk patients? Scand J Gastroenterol 2008; 43:593-6. [PMID: 18415753 DOI: 10.1080/00365520701851673] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Cholecystectomy is the standard treatment for acute cholecystitis, but in high-risk patients with serious comorbidity and in patients of advanced age there is substantial morbidity and mortality associated with the intervention. In these selected patients, percutaneous cholecystostomy (PCS) is an alternative mode of management. The aim of the present study was to evaluate the outcome of PCS in selected patients with acute cholecystitis. MATERIAL AND METHODS Thirty-five patients, representing 0.6% of all acute cholecystitis patients managed during the period 1994-2003, were subjected to PCS. Patients' charts were reviewed retrospectively for age, gender, comorbidity, hospital stay, procedure, complications and final outcome, including requirement of additional interventions. RESULTS PCS was considered successful in 34/35 patients, 26 of whom responded within 3 days. Two patients required additional cholecystectomy 3 days and 20 months, respectively, after the PCS procedure. Two patients underwent endoscopic retrograde cholangiopancreatography (ERCP) and one patient underwent rotation lithotripsy. Four patients suffered recurrent biliary complaints after the acute episode of cholecystitis, while the only serious procedure-related complication was bile leakage from the gallbladder in one patient, which necessitated cholecystectomy. CONCLUSIONS PCS is a comparatively safe and efficient procedure in the treatment of acute cholecystitis in high-risk patients with serious comorbidity and in elderly patients, contraindicating the general anaesthesia required for laparoscopic or open cholecystectomy.
Collapse
Affiliation(s)
- Per Leveau
- Department of Surgery, Lund University Hospital, Lund, Sweden
| | | | | | | | | |
Collapse
|
22
|
Vakkala M, Laurila JJ, Saarnio J, Koivukangas V, Syrjälä H, Karttunen T, Soini Y, Ala-Kokko TI. Cellular turnover and expression of hypoxic-inducible factor in acute acalculous and calculous cholecystitis. Crit Care 2008; 11:R116. [PMID: 17974017 PMCID: PMC2556769 DOI: 10.1186/cc6170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 10/31/2007] [Accepted: 10/31/2007] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION Epithelial corrective and destructive mechanisms have not been studied in inflammatory gallbladder disease. METHODS Epithelial apoptosis, cell proliferation and expression of hypoxia-inducible factor (HIF)-1alpha were compared in gallbladders from patients with acute acalculous cholecystitis (AAC; n = 30) and acute calculous cholecystitis (ACC; n = 21), and from patients undergoing surgery for other reasons (normal gallbladders; n = 9), which were removed during open cholecystectomy. The immunohistochemical stains included antibodies to Ki-67 (proliferation), M30 (apoptosis) and HIF-1alpha. Proliferation and apoptosis were expressed as percentages of positive cells. HIF-1alpha expression was expressed as absent, weak, or strong. RESULTS Apoptosis (median [25th to 75th percentile]) was significantly increased in AAC (1.31% [0.75% to 1.8%], P < 0.001) and ACC (1.10% [0.63% to 1.64%], P = 0.001), compared with control samples (0.20% [0.07% to 0.45%]. The proliferation rate was significantly increased in AAC (8.0% [4.0% to 17.0%], P < 0.001) and ACC (14% [7.5% to 26.5%], P = 0.001) compared with control samples (1.0% [1.0% to 3.0%]). Strong HIF-1alpha staining was observed in 57% of AAC, in 100% of ACC and in 44% of control specimens (P < 0.001). Intense HIF-1alpha expression was associated with increased cell proliferation (P = 0.002). CONCLUSION Cell proliferation and apoptosis were increased in AAC and ACC, as compared with normal gallbladders. Expression of HIF-1alpha was lower in AAC than in ACC.
Collapse
Affiliation(s)
- Merja Vakkala
- Department of Anesthesiology, Division of Intensive Care, Oulu University Hospital, Kajaanintie 52, Oulu, Finland, FIN-90029
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Bagherie-Lachidan M, Wright SI, Kelly SP. Claudin-3 tight junction proteins in Tetraodon nigroviridis: cloning, tissue-specific expression, and a role in hydromineral balance. Am J Physiol Regul Integr Comp Physiol 2008; 294:R1638-47. [PMID: 18353883 DOI: 10.1152/ajpregu.00039.2008] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Claudins are a large family of integral transmembrane tight junction (TJ) proteins involved in regulating the permeability of the paracellular pathway. In these studies, we clone and describe the tissue distribution of four claudin-3 genes (designated Tncldn3a, Tncldn3b, Tncldn3c, and Tncldn3d) from the euryhaline spotted green puffer fish Tetraodon nigroviridis and examine the response of Tetraodon and Tncldn3 mRNAs to salinity variation (freshwater, FW; seawater, SW; and hypersaline seawater, HSW). In Tetraodon, genes encoding for claudin-3 TJ proteins are widely expressed, suggesting that claudin-3 proteins participate in regulating paracellular permeability across various epithelia within fishes. Of particular note is the widespread distribution of Tncldn3 genes in tissues that regulate hydromineral balance (gills, skin, kidney, and intestine). Renal and intestinal tissues express all four Tncldn3 genes, while the gills and skin specifically express Tncldn3a and Tncldn3c. In response to salinity variation, Tetraodon exhibits characteristics typical of a euryhaline fish species: moderate changes in blood osmolality and muscle moisture content; alterations in gill, kidney, and intestinal Na(+)-K(+)-ATPase activity; and unaltered Na(+)-K(+)-ATPase activity in the integument. In conjunction with these changes, Tncldn3 mRNA expression exhibits marked and significant salinity-dependent alterations that are both tissue and gene specific. Overall, our data suggest that a decreased abundance of claudin-3 in Tetraodon occurs in "leakier" epithelia and that claudin-3 TJ proteins will likely play an important role in the maintenance of hydromineral balance across osmoregulatory epithelia of euryhaline fishes.
Collapse
|
24
|
Krause G, Winkler L, Mueller SL, Haseloff RF, Piontek J, Blasig IE. Structure and function of claudins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1778:631-45. [PMID: 18036336 DOI: 10.1016/j.bbamem.2007.10.018] [Citation(s) in RCA: 576] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Revised: 10/18/2007] [Accepted: 10/19/2007] [Indexed: 01/09/2023]
Abstract
Claudins are tetraspan transmembrane proteins of tight junctions. They determine the barrier properties of this type of cell-cell contact existing between the plasma membranes of two neighbouring cells, such as occurring in endothelia or epithelia. Claudins can completely tighten the paracellular cleft for solutes, and they can form paracellular ion pores. It is assumed that the extracellular loops specify these claudin functions. It is hypothesised that the larger first extracellular loop is critical for determining the paracellular tightness and the selective ion permeability. The shorter second extracellular loop may cause narrowing of the paracellular cleft and have a holding function between the opposing cell membranes. Sequence analysis of claudins has led to differentiation into two groups, designated as classic claudins (1-10, 14, 15, 17, 19) and non-classic claudins (11-13, 16, 18, 20-24), according to their degree of sequence similarity. This is also reflected in the derived sequence-structure function relationships for extracellular loops 1 and 2. The concepts evolved from these findings and first tentative molecular models for homophilic interactions may explain the different functional contribution of the two extracellular loops at tight junctions.
Collapse
Affiliation(s)
- Gerd Krause
- Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, 13125 Berlin, Germany
| | | | | | | | | | | |
Collapse
|