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Crifo B, MacNaughton WK. Cells and mediators of inflammation as effectors of epithelial repair in the inflamed intestine. Am J Physiol Gastrointest Liver Physiol 2022; 322:G169-G182. [PMID: 34878937 DOI: 10.1152/ajpgi.00194.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Mucosal and histological healing have become the gold standards for assessing the efficacy of therapy in patients living with inflammatory bowel diseases (IBD). Despite these being the accepted goals in therapy, the mechanisms that underlie the healing of the mucosa after an inflammatory insult are not well understood, and many patients fail to meet this therapeutic endpoint. Here we review the emerging evidence that mediators (e.g., prostaglandins, cytokines, proteases, reactive oxygen, and nitrogen species) and innate immune cells (e.g., neutrophils and monocytes/macrophages), that are involved in the initiation of the inflammatory response, are also key players in the mechanisms underlying mucosal healing to resolve chronic inflammation in the colon. The dual function mediators comprise an inflammation/repair program that returns damaged tissue to homeostasis. Understanding details of the dual mechanisms of these mediators and cells may provide the basis for the development of drugs that can help to stimulate epithelial repair in patients affected by IBD.
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Affiliation(s)
- Bianca Crifo
- Department of Physiology and Pharmacology, Inflammation Research Network and Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Wallace K MacNaughton
- Department of Physiology and Pharmacology, Inflammation Research Network and Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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2
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Lambertini C, Zannoni A, Romagnoli N, Bombardi C, Morini M, Dondi F, Bernardini C, Forni M, Rinnovati R, Spadari A. Expression of Proteinase-Activated Receptor 2 During Colon Volvulus in the Horse. Front Vet Sci 2020; 7:589367. [PMID: 33330716 PMCID: PMC7728609 DOI: 10.3389/fvets.2020.589367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 10/27/2020] [Indexed: 11/16/2022] Open
Abstract
Large colon volvulus in horses is associated with a poor prognosis, especially when ischemic-reperfusion injury of the affected intestinal tract develops. Proteinase-activated receptor 2 (PAR2) plays an important role in the pathogenesis of inflammation in the gastrointestinal tract. The aim of this study was to evaluate the distribution and expression of PAR2 in colonic pelvic flexure of horses spontaneously affected by large colon volvulus (CVH group). Eight horses admitted for severe abdominal colon volvolus and which underwent surgery were included. Colon samples were collected after enterotomy. Data previously obtained from healthy horses were used as a control group. Histologic evaluation was carried out to grade the severity of the colon lesions. Immunofluorescence, western blot and quantitative polymerase chain reaction (RT-qPCR) were carried out on colon samples to evaluate PAR2 expression. In addition, the transcriptional profile of cytokines and chemokines was evaluated using RT2 Profiler™ PCR Array Horse Cytokines & Chemokines. Three out of the eight patients were euthanised due to clinical deterioration. Immunostaining for PAR2 was observed in the enterocytes, intestinal glands and neurons of the submucosal and myenteric plexi. In the CVH horses, the expression of PAR2 mesenger RNA (mRNA) did not differ significantly from that of the healthy animals; western blots of the mucosa of the colon tracts showed a clear band of the expected molecular weight for PAR2 (~44 kDa) and a band smaller than the expected molecular weight for PAR2 (25kDa), suggesting its activation. The gene expressions for C-X-C motif ligand 1 (CXCL1); interleukin 8 (IL8), macrophage inflammatory protein 2 beta (MIP-2BETA) were upregulated in the colic horses as compared with the colons of the healthy horses. Therefore, in the present study, the expression and activation of PAR2 in the colons of horses in the presence of an inflammatory reaction like that occurring in those with spontaneous colon volvulus was confirmed.
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Affiliation(s)
- Carlotta Lambertini
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Augusta Zannoni
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Noemi Romagnoli
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Cristiano Bombardi
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Maria Morini
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Francesco Dondi
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Chiara Bernardini
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Monica Forni
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Riccardo Rinnovati
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Alessandro Spadari
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
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3
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Boucher AA, Rosenfeldt L, Mureb D, Shafer J, Sharma BK, Lane A, Crowther RR, McKell MC, Whitt J, Alenghat T, Qualls J, Antoniak S, Mackman N, Flick MJ, Steinbrecher KA, Palumbo JS. Cell type-specific mechanisms coupling protease-activated receptor-1 to infectious colitis pathogenesis. J Thromb Haemost 2020; 18:91-103. [PMID: 31539206 PMCID: PMC7026906 DOI: 10.1111/jth.14641] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 08/29/2019] [Accepted: 09/16/2019] [Indexed: 12/12/2022]
Abstract
BACKGROUND Protease-activated receptor-1 (PAR-1) plays a major role in multiple disease processes, including colitis. Understanding the mechanisms coupling PAR-1 to disease pathogenesis is complicated by the fact that PAR-1 is broadly expressed across multiple cell types. OBJECTIVE Determine the specific contributions of PAR-1 expressed by macrophages and colonic enterocytes to infectious colitis. METHODS Mice carrying a conditional PAR-1 allele were generated and bred to mice expressing Cre recombinase in a myeloid- (PAR-1ΔM ) or enterocyte-specific (PAR-1ΔEPI ) fashion. Citrobacter rodentium colitis pathogenesis was analyzed in mice with global PAR-1 deletion (PAR-1-/- ) and cell type-specific deletions. RESULTS Constitutive deletion of PAR-1 had no significant impact on weight loss, crypt hypertrophy, crypt abscess formation, or leukocyte infiltration in Citrobacter colitis. However, colonic shortening was significantly blunted in infected PAR-1-/- mice, and these animals exhibited decreased local levels of IL-1β, IL-22, IL-6, and IL-17A. In contrast, infected PAR-1ΔM mice lost less weight and had fewer crypt abscesses relative to controls. PAR-1ΔM mice had diminished CD3+ T cell infiltration into colonic tissue, but macrophage and CD4+ T cell infiltration were similar to controls. Also contrasting results in global knockouts, PAR-1ΔM mice exhibited lower levels of IL-1β, but not Th17-related cytokines (ie, IL-22, IL-6, IL-17A). Infected PAR-1ΔEPI mice exhibited increased crypt hypertrophy and crypt abscess formation, but local cytokine elaboration was similar to controls. CONCLUSIONS These studies reveal complex, cell type-specific roles for PAR-1 in modulating the immune response to Citrobacter colitis that are not readily apparent in analyses limited to mice with global PAR-1 deficiency.
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Affiliation(s)
- Alexander A. Boucher
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Leah Rosenfeldt
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Duaa Mureb
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Jessica Shafer
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Bal Krishan Sharma
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Adam Lane
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Rebecca R. Crowther
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, Ohio
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Melanie C. McKell
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
- Immunology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Jordan Whitt
- Division of Immunobiology and Center for Inflammation and Tolerance, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Theresa Alenghat
- Division of Immunobiology and Center for Inflammation and Tolerance, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Joseph Qualls
- Division of Infectious Diseases, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Silvio Antoniak
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Nigel Mackman
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Matthew J. Flick
- Department of Pathology and Laboratory Medicine, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Kris A. Steinbrecher
- Division of Gastroenterology, Cincinnati Children’s Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Joseph S. Palumbo
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
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4
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Pontarollo G, Mann A, Brandão I, Malinarich F, Schöpf M, Reinhardt C. Protease-activated receptor signaling in intestinal permeability regulation. FEBS J 2019; 287:645-658. [PMID: 31495063 DOI: 10.1111/febs.15055] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 08/01/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022]
Abstract
Protease-activated receptors (PARs) are a unique class of G-protein-coupled transmembrane receptors, which revolutionized the perception of proteases from degradative enzymes to context-specific signaling factors. Although PARs are traditionally known to affect several vascular responses, recent investigations have started to pinpoint the functional role of PAR signaling in the gastrointestinal (GI) tract. This organ is exposed to the highest number of proteases, either from the gut lumen or from the mucosa. Luminal proteases include the host's digestive enzymes and the proteases released by the commensal microbiota, while mucosal proteases entail extravascular clotting factors and the enzymes released from resident and infiltrating immune cells. Active proteases and, in case of a disrupted gut barrier, even entire microorganisms are capable to translocate the intestinal epithelium, particularly under inflammatory conditions. Especially PAR-1 and PAR-2, expressed throughout the GI tract, impact gut permeability regulation, a major factor affecting intestinal physiology and metabolic inflammation. In addition, PARs are critically involved in the onset of inflammatory bowel diseases, irritable bowel syndrome, and tumor progression. Due to the number of proteases involved and the multiple cell types affected, selective regulation of intestinal PARs represents an interesting therapeutic strategy. The analysis of tissue/cell-specific knockout animal models will be of crucial importance to unravel the intrinsic complexity of this signaling network. Here, we provide an overview on the implication of PARs in intestinal permeability regulation under physiologic and disease conditions.
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Affiliation(s)
- Giulia Pontarollo
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany
| | - Amrit Mann
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany
| | - Inês Brandão
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany.,Centro de Apoio Tecnológico Agro Alimentar (CATAA), Zona Industrial de Castelo Branco, Portugal
| | - Frano Malinarich
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany
| | - Marie Schöpf
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany
| | - Christoph Reinhardt
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Johannes Gutenberg University of Mainz, Germany.,German Center for Cardiovascular Research (DZHK), Partner Site RheinMain, Mainz, Germany
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5
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Malfettone A, Silvestris N, Saponaro C, Ranieri G, Russo A, Caruso S, Popescu O, Simone G, Paradiso A, Mangia A. High density of tryptase-positive mast cells in human colorectal cancer: a poor prognostic factor related to protease-activated receptor 2 expression. J Cell Mol Med 2014; 17:1025-37. [PMID: 23991686 PMCID: PMC3780541 DOI: 10.1111/jcmm.12073] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 04/01/2013] [Indexed: 12/11/2022] Open
Abstract
Tryptase(+) mast cells (MCs), abundant in the invasive front of tumours, contribute to tissue remodelling. Indeed, protease-activated receptor-2 (PAR-2) activation by MC-tryptase is considered an oncogenic event in colorectal cancer (CRC). Recently, we have suggested NHERF1 as a potential new marker in CRC. In this study, we aimed to determine the distribution of tryptase(+) MCs and PAR-2 and to examine the relationship between PAR-2 and NHERF1, investigating their reputed usefulness as tumour markers. We studied a cohort of 115 CRC specimens including primary cancer (C) and adjacent normal mucosa (NM) by immunohistochemical double staining, analyzing the protein expression of MC-tryptase, PAR-2 and cytoplasmic NHERF1. MC density was higher in NM than in C. Tumours with high TNM stage and poor grade showed the highest MC density. A higher PAR-2 immunoreactivity characterized tumours most infiltrated by MCs compared with samples with low MC density. Furthermore, PAR-2 overexpression was associated with advanced TNM stage, poor grade and lymphovascular invasion (LVI). A positive correlation existed between tryptase(+) MC density and PAR-2 expression. Cytoplasmic NHERF1 was higher in C than in NM and overexpressing tumours resulted associated with nodal and distant metastases, poor grade and LVI. PAR-2 correlated with cytoplasmic NHERF1 and the PAR-2(+)/cytoplasmic NHERF1(+) expression immunophenotype identified tumours associated with unfavourable prognosis and aggressive clinical parameters. Our data indicate that the high density of tryptase(+) MCs at invasive margins of tumours was associated with advanced stages of CRC and was strongly correlated with PAR-2 expression.
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Affiliation(s)
- Andrea Malfettone
- Functional Biomorphology Laboratory, National Cancer Research Centre, Giovanni Paolo II, Bari, Italy
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6
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Zamolodchikova TS. Serine proteases of small intestine mucosa--localization, functional properties, and physiological role. BIOCHEMISTRY (MOSCOW) 2013; 77:820-9. [PMID: 22860904 DOI: 10.1134/s0006297912080032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this review we present data about small intestine serine proteases, which are a considerable part of the proteolytic apparatus in this major part of the gastrointestinal tract. Serine proteases of intestinal epitheliocytes, their structural-functional features, cellular localization, physiological substrates, and mechanisms of activity regulation are examined. Information about biochemical and functional properties of serine proteases is presented in a common context with morphological and physiological data, this being the basis for understanding the functional processes taking place in upper part of the intestine. Serine proteases play a key role in the physiology of the small intestine and provide the normal functioning of this organ as part of the digestive system in which hydrolysis and suction of food substances occur. They participate in renewal and remodeling of tissues, retractive activity of smooth musculature, hormonal regulation, and defense mechanisms of the intestine.
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Affiliation(s)
- T S Zamolodchikova
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
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7
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White MJV, Glenn M, Gomer RH. Trypsin potentiates human fibrocyte differentiation. PLoS One 2013; 8:e70795. [PMID: 23951012 PMCID: PMC3737277 DOI: 10.1371/journal.pone.0070795] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 06/22/2013] [Indexed: 02/07/2023] Open
Abstract
Trypsin-containing topical treatments can be used to speed wound healing, although the mechanism of action is unknown. To help form granulation tissue and heal wounds, monocytes leave the circulation, enter the wound tissue, and differentiate into fibroblast-like cells called fibrocytes. We find that 20 to 200 ng/ml trypsin (concentrations similar to those used in wound dressings) potentiates the differentiation of human monocytes to fibrocytes in cell culture. Adding trypsin inhibitors increases the amount of trypsin needed to potentiate fibrocyte differentiation, suggesting that the potentiating effect is dependent on trypsin proteolytic activity. Proteases with other site specificities such as pepsin, endoprotease GluC, and chymotrypsin do not potentiate fibrocyte differentiation. This potentiation requires the presence of albumin in the culture medium, and tryptic fragments of human or bovine albumin also potentiate fibrocyte differentiation. These results suggest that topical trypsin speeds wound healing by generating tryptic fragments of albumin, which in turn potentiate fibrocyte differentiation.
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Affiliation(s)
- Michael J. V. White
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Melissa Glenn
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Richard H. Gomer
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
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8
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Khazaie K, Blatner NR, Khan MW, Gounari F, Gounaris E, Dennis K, Bonertz A, Tsai FN, Strouch MJ, Cheon E, Phillips JD, Beckhove P, Bentrem DJ. The significant role of mast cells in cancer. Cancer Metastasis Rev 2011; 30:45-60. [PMID: 21287360 DOI: 10.1007/s10555-011-9286-z] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mast cells (MC) are a bone marrow-derived, long-lived, heterogeneous cellular population that function both as positive and negative regulators of immune responses. They are arguably the most productive chemical factory in the body and influence other cells through both soluble mediators and cell-to-cell interaction. MC are commonly seen in various tumors and have been attributed alternatively with tumor rejection or tumor promotion. Tumor-infiltrating MC are derived both from sentinel and recruited progenitor cells. MC can directly influence tumor cell proliferation and invasion but also help tumors indirectly by organizing its microenvironment and modulating immune responses to tumor cells. Best known for orchestrating inflammation and angiogenesis, the role of MC in shaping adaptive immune responses has become a focus of recent investigations. MC mobilize T cells and antigen-presenting dendritic cells. They function as intermediaries in regulatory T cells (Treg)-induced tolerance but can also modify or reverse Treg-suppressive properties. The central role of MC in the control of innate and adaptive immunity endows them with the ability to tune the nature of host responses to cancer and ultimately influence the outcome of disease and fate of the cancer patient.
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Affiliation(s)
- Khashayarsha Khazaie
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Feinberg School of Medicine, 303 East Superior Street, Lurie 3-250, Chicago, IL 60611, USA.
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9
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Xu H, Echemendia N, Chen S, Lin F. Identification and expression patterns of members of the protease-activated receptor (PAR) gene family during zebrafish development. Dev Dyn 2011; 240:278-87. [PMID: 21181945 DOI: 10.1002/dvdy.22517] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Protease-activated receptors (PARs) play critical roles in hemostasis in vertebrates including zebrafish. However, the zebrafish gene classification appears to be complex, and the expression patterns of par genes are not established. Based on analyses of genomic organization, phylogenetics, protein primary structure, and protein internalization, we report the identification of four zebrafish PARs: par1, par2a, par2b, and par3. This classification differs from one reported previously. We also show that these genes have distinct spatiotemporal expression profiles in embryos and larvae, with par1, par2a, and par2b expressed maternally and ubiquitously during gastrula stages and their expression patterns refined at later stages, and par3 expressed only in 3-day-old larvae. Notably, the expression patterns of zebrafish par1 and par2b resemble those of their mammalian counterparts, suggesting that receptor function is conserved among vertebrates. This conservation is supported by our findings that Par1 and Par2b are internalized following exposure to thrombin and trypsin, respectively.
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Affiliation(s)
- Hui Xu
- Department of Anatomy and Cell Biology, Carver College of Medicine, the University of Iowa, Iowa City, Iowa 52242-1109, USA
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10
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Lundgren O, Jodal M, Jansson M, Ryberg AT, Svensson L. Intestinal epithelial stem/progenitor cells are controlled by mucosal afferent nerves. PLoS One 2011; 6:e16295. [PMID: 21347406 PMCID: PMC3036584 DOI: 10.1371/journal.pone.0016295] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 12/22/2010] [Indexed: 01/07/2023] Open
Abstract
Background The maintenance of the intestinal epithelium is of great importance for the survival of the organism. A possible nervous control of epithelial cell renewal was studied in rats and mice. Methods Mucosal afferent nerves were stimulated by exposing the intestinal mucosa to capsaicin (1.6 mM), which stimulates intestinal external axons. Epithelial cell renewal was investigated in the jejunum by measuring intestinal thymidine kinase (TK) activity, intestinal 3H-thymidine incorporation into DNA, and the number of crypt cells labeled with BrdU. The influence of the external gut innervation was minimized by severing the periarterial nerves. Principal Findings Luminal capsaicin increased all the studied variables, an effect nervously mediated to judge from inhibitory effects on TK activity or 3H-thymidine incorporation into DNA by exposing the mucosa to lidocaine (a local anesthetic) or by giving four different neurotransmitter receptor antagonists i.v. (muscarinic, nicotinic, neurokinin1 (NK1) or calcitonin gene related peptide (CGRP) receptors). After degeneration of the intestinal external nerves capsaicin did not increase TK activity, suggesting the involvement of an axon reflex. Intra-arterial infusion of Substance P (SP) or CGRP increased intestinal TK activity, a response abolished by muscarinic receptor blockade. Immunohistochemistry suggested presence of M3 and M5 muscarinic receptors on the intestinal stem/progenitor cells. We propose that the stem/progenitor cells are controlled by cholinergic nerves, which, in turn, are influenced by mucosal afferent neuron(s) releasing acetylcholine and/or SP and/or CGRP. In mice lacking the capsaicin receptor, thymidine incorporation into DNA and number of crypt cells labeled with BrdU was lower than in wild type animals suggesting that nerves are important also in the absence of luminal capsaicin, a conclusion also supported by the observation that atropine lowered thymidine incorporation into DNA by 60% in control rat segments. Conclusion Enteric nerves are of importance in maintaining the intestinal epithelial barrier.
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Affiliation(s)
- Ove Lundgren
- Section of Physiology, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.
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11
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Chung WO, An J, Yin L, Hacker BM, Rohani MG, Dommisch H, DiJulio DH. Interplay of protease-activated receptors and NOD pattern recognition receptors in epithelial innate immune responses to bacteria. Immunol Lett 2010; 131:113-9. [PMID: 20219537 PMCID: PMC2885501 DOI: 10.1016/j.imlet.2010.02.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 02/01/2010] [Accepted: 02/11/2010] [Indexed: 01/01/2023]
Abstract
Protease-activated receptors (PARs), nucleotide-binding oligomerization domain (NOD) receptors and Toll-like receptors (TLRs) play a role in innate immunity, but little is known about interaction between these receptors. The goal of this study was to investigate how silencing one receptor affects the expression of other receptors and downstream innate immune markers in response to bacteria. Human gingival epithelial cells (GECs) were transfected with siRNA specific for PAR1 or PAR2, then stimulated with periopathogen Porphyromonas gingivalis, bridging organism between pathogens and non-pathogens Fusobacterium nucleatum, or non-pathogen Streptococcus gordonii. PAR1 or PAR2 knock-down resulted in up-regulated NOD1 and NOD2 expression with P. gingivalis or F. nucleatum stimulation (p<0.01), as well as enhanced TLR2 and TLR4 expression when cells were stimulated by bacteria that utilize TLR2 or TLR4, respectively. Involvement of PARs for induction of CC chemokine ligand 20 (CCL20), a cytokine with antimicrobial properties, was observed following stimulation of the three bacterial species. Furthermore, results from multiple cytokine ELISA array showed receptors utilized in the induction of various innate immune markers are tailored to individual bacterium tested. Our data suggest complex interplay of several receptors is required for appropriate innate immune responses to the different types of bacteria present within the oral cavity and that receptor expression itself is altered depending on which organism the cell encounters.
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Affiliation(s)
- Whasun O. Chung
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
| | - Jonathan An
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
| | - Lei Yin
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
| | - Beth M. Hacker
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
| | - Maryam G. Rohani
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
| | - Henrik Dommisch
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
- Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Bonn, Germany
| | - Dennis H. DiJulio
- Department of Oral Biology, University of Washington, Seattle, WA 98195-7132
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12
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Wang H, Moreau F, Hirota CL, MacNaughton WK. Proteinase-activated receptors induce interleukin-8 expression by intestinal epithelial cells through ERK/RSK90 activation and histone acetylation. FASEB J 2010; 24:1971-80. [PMID: 20065107 DOI: 10.1096/fj.09-137646] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Proteinase-activated receptors (PARs) are involved in both inflammation and tumorigenesis in epithelial cells. Interleukin (IL)-8 is a potent chemoattractant and is also involved in angiogenesis. The molecular mechanism whereby PARs induce epithelial IL-8 expression is not known. In HT-29 colonic epithelial cells, PAR(1) or PAR(2) agonists stimulated the expression of IL-8 through a NF-kappaB-dependent pathway without inducing IkappaB degradation and disassociation of IkappaB from NF-kappaB. Further studies revealed that PAR activation induced the phosphorylation of p65 at Ser-276 in the nucleus, which increased the recruitment of histone acetyltransferase (HAT) p300 to p50. Inhibition of ERK activation completely blocked PAR-induced IL-8 expression, phosphorylation of p65 and HAT activity. We also demonstrated that RSK p90 was the downstream kinase that mediated ERK-induced nuclear p65 phosphorylation. In conclusion, activation of either PAR(1) or PAR(2) stimulated the transcriptional up-regulation of IL-8 in HT-29 colonic epithelial cells through a pathway that involved ERK/RSK p90, NF-kappaB phosphorylation, and HAT activity. These studies provide evidence of a new role for serine proteinases and PARs in the regulation of gene expression in colonic inflammation and tumorigenesis.
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Affiliation(s)
- Hongying Wang
- Inflammation Research Network, University of Calgary, Calgary, AB, Canada
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13
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Bian ZX, Li Z, Huang ZX, Zhang M, Chen HL, Xu HX, Sung JJY. Unbalanced expression of protease-activated receptors-1 and -2 in the colon of diarrhea-predominant irritable bowel syndrome patients. J Gastroenterol 2009; 44:666-74. [PMID: 19430717 DOI: 10.1007/s00535-009-0058-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Accepted: 03/10/2009] [Indexed: 02/04/2023]
Abstract
OBJECTIVE The aim of this study is to determine whether a changed expression ratio of PAR-1 and PAR-2 in the colon is associated with diarrhea-predominant IBS patients. METHODS PAR-1, -2, thrombin, mast cell tryptase, tryptophan hydroxylase (TPH), and chromgranin A (ChrA) in colonic biopsy samples from 10 diarrhea-predominant IBS patients and 13 healthy control subjects were semiquantified with immunofluorescence and image analysis. Serotonin concentrations in biopsy samples were evaluated by capillary electrophoresis. RESULTS Significantly lower expression of PAR-1 and higher expression of mast cell tryptase was detected in the colons of patients, with statistically unchanged expression of PAR-2. Thrombin-, TPH-, and ChrA-positive cells were markedly increased in IBS patients, but no significant difference in serotonin concentration existed in the colons between two groups. The ratio of PAR-1/PAR-2 expression was significantly decreased in patients (0.33+/-0.19 versus 0.66+/-0.22, P=0.001) and negatively correlated to ChrA-positive cells. CONCLUSIONS Changed expression ratio of PAR-1 to PAR-2 in the colon is connected with diarrhea-predominant IBS patients. Methods to restore an appropriate balance of PAR-1 and PAR-2 activation in the colon may offer a promising future therapeutic strategy for IBS patients.
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Affiliation(s)
- Zhao Xiang Bian
- School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China.
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14
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Swystun VA, Renaux B, Moreau F, Wen S, Peplowski MA, Hollenberg MD, MacNaughton WK. Serine proteases decrease intestinal epithelial ion permeability by activation of protein kinase Czeta. Am J Physiol Gastrointest Liver Physiol 2009; 297:G60-70. [PMID: 19460843 DOI: 10.1152/ajpgi.00096.2009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Epithelial permeability to ions and larger molecules in the gut is essential for fluid balance, and its dysregulation contributes to intestinal pathology. We investigated the effect of digestive serine proteases on epithelial paracellular permeability. Trypsin, chymotrypsin, and elastase elicited sustained increases in transepithelial resistance (R(TE)) in polarized monolayers of three intestinal epithelial cell lines. This effect was reflected by decreases in paracellular conductances of Na+ and Cl- and a concomitant decrease in permeability to 3,000 molecular weight dextran. The enzyme activities of the proteases were required, yet activators of known protease-activated receptors (PARs) did not reproduce the effect of these proteases on R(TE). PKCzeta isoform-specific inhibitor significantly reduced the trypsin-induced increase in R(TE) whereas PKCzeta activity was increased in cells treated with trypsin and chymotrypsin compared with control cells; this activity was reduced to control levels in the presence of PKCzeta-specific inhibitor. Ca2+ chelators and pharmacological inhibitors of cell signaling support the role for PKCzeta in the protease-induced effect. Finally, we showed that treatment with the serine proteases increased occludin immunostaining and zonula occludin-1 coimmunoprecipitation with occludin in the detergent-insoluble fraction of cell lysates, and these increases were ablated by pretreatment with PKCzeta-specific inhibitor. This finding indicates increased insertion of occludin into the cell junctional complex. These data demonstrate a role for serine proteases in the facilitation of epithelial barrier function through a mechanism that is independent of PARs and is mediated by activation of PKCzeta.
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Affiliation(s)
- Veronica A Swystun
- Inflammation Research Network, Department of Physiology and Pharmacology, University of Calgary, Calgary T2N 4N1, Canada
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15
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Rohani MG, Beyer RP, Hacker BM, Dommisch H, Dale BA, Chung WO. Modulation of expression of innate immunity markers CXCL5/ENA-78 and CCL20/MIP3alpha by protease-activated receptors (PARs) in human gingival epithelial cells. Innate Immun 2009; 16:104-14. [PMID: 19567485 DOI: 10.1177/1753425909339233] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Protease-activated receptors (PARs) are G-protein-coupled receptors with an active role in host defense. The two most highly expressed members of the PAR family in gingival epithelial cells (GECs) are PAR1 and PAR2. The major virulence factors of periodontal pathogen Porphyromonas gingivalis are its proteases which can activate PAR2. However, little is known about the function of PARs in GECs when they are activated by their endogenous agonist enzymes. The purpose of this study was to characterize how the expression of innate immune markers is modulated when PAR1 and PAR2 are activated by their agonist enzymes, thrombin and trypsin, respectively. Here, we report that activation of PAR1 and PAR2 induces cell proliferation at low concentration. Activation of PAR via proteolytic activity of thrombin and trypsin induces expression of CXCL5/ENA-78 and CCL20/MIP3alpha in a concentration-dependent manner. Induction of CXCL5 via PAR1 was inhibited in the presence of PAR1 cleavage blocking antibodies and by PAR1 siRNA. The induction of CXCL5 and CCL20 via PAR2 was inhibited by PAR2 siRNA. These findings indicate an active role in innate immune responses by PAR1 and PAR2 in GECs. Modulation of innate immunity by PARs may contribute to co-ordinated and balanced immunosurveillance in GECs.
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Affiliation(s)
- Maryam G Rohani
- Department of Oral Biology, University of Washington, Seattle, Washington 98195-7132, USA
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16
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Søreide K. Proteinase-activated receptor 2 (PAR-2) in gastrointestinal and pancreatic pathophysiology, inflammation and neoplasia. Scand J Gastroenterol 2008; 43:902-9. [PMID: 19086162 DOI: 10.1080/00365520801942141] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Of all the body systems, the gastrointestinal (GI) tract is the most exposed to proteinases. Proteolytic activity must thus be tightly regulated in the face of diverse environmental challenges, because unrestrained or excessive proteolysis leads to pathological GI conditions. The protease-activated receptor-2 (PAR-2) is expressed in numerous cell types within the GI tract, suggesting both multiple functions and numerous modes of receptor activation. Although best known as a pancreatic digestive enzyme, trypsin has also been found in other tissues and various cancers. Of interest, trypsin and PAR-2 act together in an autocrine loop that promotes proliferation, invasion and metastasis in neoplasia through various mechanisms. Trypsin and PAR-2 seem to act both directly and indirectly through activation of other proteinase cascades, including metalloproteinases. PAR-2 activation can participate in inflammatory reactions, be protective to mucosal surfaces, send or inhibit nociceptive messages, modify gut motility or secretory functions, and stimulate cell proliferation and motility. Several studies point to a role for the PARs in disease processes of the GI tract and pancreas ranging from inflammatory bowel disease, symptoms associated with irritable bowel syndrome, pain in pancreatitis, development of colon and other GI cancers, and even infectious colitis. Proteinases should not only be considered from the traditional view as digestive or degradative enzymes in the gut, but additionally as signalling molecules that actively participate in the spectrum of physiology and diseased states of the GI tract.
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Affiliation(s)
- Kjetil Søreide
- Department of Surgery, Stavanger University Hospital, Stavanger, Norway.
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17
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Kawada M, Arihiro A, Mizoguchi E. Insights from advances in research of chemically induced experimental models of human inflammatory bowel disease. World J Gastroenterol 2007; 13:5581-93. [PMID: 17948932 PMCID: PMC4172737 DOI: 10.3748/wjg.v13.i42.5581] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Inflammatory bowel disease (IBD), the most important being Crohn's disease and ulcerative colitis, results from chronic dysregulation of the mucosal immune system in the gastrointestinal tract. Although the pathogenesis of IBD remains unclear, it is widely accepted that genetic, environmental, and immunological factors are involved. Recent studies suggest that intestinal epithelial defenses are important to prevent inflammation by protecting against microbial pathogens and oxidative stresses. To investigate the etiology of IBD, animal models of experimental colitis have been developed and are frequently used to evaluate new anti-inflammatory treatments for IBD. Several models of experimental colitis that demonstrate various pathophysiological aspects of the human disease have been described. In this manuscript, we review the characteristic features of IBD through a discussion of the various chemically induced experimental models of colitis (e.g., dextran sodium sulfate-, 2,4,6-trinitrobenzene sulfonic acid-, oxazolone-, acetic acid-, and indomethacin-induced models). We also summarize some regulatory and pathogenic factors demonstrated by these models that can, hopefully, be exploited to develop future therapeutic strategies against IBD.
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18
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Antalis TM, Shea-Donohue T, Vogel SN, Sears C, Fasano A. Mechanisms of disease: protease functions in intestinal mucosal pathobiology. ACTA ACUST UNITED AC 2007; 4:393-402. [PMID: 17607295 PMCID: PMC3049113 DOI: 10.1038/ncpgasthep0846] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 04/20/2007] [Indexed: 12/16/2022]
Abstract
Of all our organ systems, the gastrointestinal tract contains the highest levels of endogenous and exogenous proteases (also known as proteinases and peptidases); however, our understanding of their functions and interactions within the gastrointestinal tract is restricted largely to nutrient digestion. The gut epithelium is a sensor of the luminal environment, not only controlling digestive, absorptive and secretory functions, but also relaying information to the mucosal immune, vascular and nervous systems. These functions involve a complex array of cell types that elaborate growth factors, cytokines and extracellular matrix (ECM) proteins, the activity and availability of which are regulated by proteases. Proteolytic activity must be tightly regulated in the face of diverse environmental challenges, because unrestrained or excessive proteolysis leads to pathological gastrointestinal conditions. Moreover, enteric microbes and parasites can hijack proteolytic pathways through 'pathogen host mimicry'. Understanding how the protease balance is maintained and regulated in the intestinal epithelial cell microenvironment and how proteases contribute to physiological and pathological outcomes will undoubtedly contribute to the identification of new potential therapeutic targets for gastrointestinal diseases.
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Affiliation(s)
| | | | | | | | - Alessio Fasano
- Correspondence, Mucosal Biology Research Center, University of Maryland School of Medicine, Room S345, HSF II Building, 20 Penn Street, Baltimore, MD 21201, USA,
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19
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Dommisch H, Chung WO, Rohani MG, Williams D, Rangarajan M, Curtis MA, Dale BA. Protease-activated receptor 2 mediates human beta-defensin 2 and CC chemokine ligand 20 mRNA expression in response to proteases secreted by Porphyromonas gingivalis. Infect Immun 2007; 75:4326-33. [PMID: 17591792 PMCID: PMC1951157 DOI: 10.1128/iai.00455-07] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The oral pathogen Porphyromonas gingivalis secretes proteases such as Arg-gingipain B (RgpB) that activate protease-activated receptors (PARs). Human beta-defensins (hBDs) and the macrophage inflammatory protein 3alpha/CC chemokine ligand 20 (CCL20) produced by epithelial cells are antimicrobial peptides that provide cytokine function and play an important role in innate immunity. The aim of the present study was to determine whether specific members of the PAR family mediate the expression of these innate immunity markers in gingival epithelial cells (GECs) when exposed to P. gingivalis cell-free culture supernatant or purified RgpB. hBD-2 mRNA in GECs was induced in response to supernatant and purified RgpB from P. gingivalis (P = 0.02 and P = 0.016, respectively). This effect was abrogated by the protease inhibitor tosyl-l-lysine chloromethyl ketone (TLCK) (P < 0.05). In response to P. gingivalis supernatant and to purified RgpB, the hBD-2 mRNA expression was significantly decreased in PAR-2 gene knockdown cells, whereas no change was detected in PAR-1 gene knockdown cells. CCL20 mRNA expression also increased in response to the supernatant of P. gingivalis, and this effect was blocked by the protease inhibitor, TLCK (P = 0.05 and P = 0.024, respectively), and was blocked in PAR-2 gene knockdown cells. Our data indicate that hBD-2 and CCL20 mRNA up-regulation by P. gingivalis supernatant and purified RgpB was mediated via PAR-2, but not via PAR-1, and that proteases play a role in the regulation of innate immune responses in GECs. GECs use PARs to recognize P. gingivalis and mediate cell responses involved in innate immunity.
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Affiliation(s)
- Henrik Dommisch
- Department of Oral Biology, School of Dentistry, University of Washington, Box 357132, Seattle, WA 98195-7132, USA.
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20
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Mitchell SE, Robinson JJ, King ME, Williams LM. Proteinase-activated receptors in ovine cervical function. Reprod Fertil Dev 2006; 17:693-9. [PMID: 16364222 DOI: 10.1071/rd05032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2005] [Accepted: 08/11/2005] [Indexed: 11/23/2022] Open
Abstract
In sheep, inflammation not only functions in cervical dilation at parturition, but also plays an important part in the non-pregnant ewe cervix, as demonstrated by the high level of expression of interleukin (IL)-8 at oestrus. Ewes artificially induced to ovulate have significantly lower levels of IL-8 gene expression at oestrus compared with natural oestrus, indicating an inhibition of inflammation and function, offering an explanation for the low rates of conception in vaginally inseminated synchronised ewes. To identify potential pro-inflammatory agents to combat the anti-inflammatory effects of hormonal synchronisation of oestrus, we have investigated the role of proteinase-activated receptor (PAR)-1 and PAR-2. To localise and measure the level of expression of these receptors, ovine-specific probes were derived for PAR-1 and PAR-2 and used for quantitative in situ hybridisation in the ovine cervix. Both PAR-1 and PAR-2 were expressed in the luminal epithelium of the cervix throughout the oestrous cycle, with expression being highest at oestrus. The gene expression of PAR-2 at oestrus was approximately 30% higher than that of PAR-1. Artificial synchronisation of oestrus by either an intravaginal progesterone sponge or prostaglandin F2+/- injections did not inhibit PAR-1 or PAR-2 expression at oestrus; rather, in the case of PAR-2, progesterone synchronisation increased it. Both synchronising procedures increased the expression of PAR-1 and PAR-2 during the luteal phase of the cycle. Therefore, agonists of PAR-1 and PAR-2 may be potentially useful pro-inflammatory agents countering the inhibition of inflammation by hormonal synchronisation.
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Affiliation(s)
- Sharon E Mitchell
- Peripheral and CNS Signalling Group, The Rowett Research Institute, Aberdeen, UK
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21
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Caruso R, Pallone F, Fina D, Gioia V, Peluso I, Caprioli F, Stolfi C, Perfetti A, Spagnoli LG, Palmieri G, Macdonald TT, Monteleone G. Protease-activated receptor-2 activation in gastric cancer cells promotes epidermal growth factor receptor trans-activation and proliferation. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 169:268-78. [PMID: 16816379 PMCID: PMC1698759 DOI: 10.2353/ajpath.2006.050841] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dysregulated epidermal growth factor receptor (EGFR) signaling is involved in gastric cancer (GC) cell growth. However, the mechanism that sustains EGFR signaling in GC remains unknown. Since protease-activated receptor-2 (PAR-2), a G protein-coupled receptor, has been shown to trans-activate EGFR in several cell types, we examined the role of PAR-2 in GC. We show here that in vitro activation of PAR-2 enhances the growth of two GC cell lines, AGS and MKN28. In both these cell lines, PAR-2 trans-activated EGFR and inhibition of EGFR tyrosine kinase activity by AG1478 or specific EGFR siRNA completely prevented PAR-2-driven proliferation. Antibody blockade of EGF-like ligands to EGFR did not modify EGFR signaling or cell growth induced by PAR-2 activation. In contrast, PAR-2 promoted Src activation and interaction of this kinase with EGFR. In support of this, inhibition of Src kinase activity by PP1 or siRNA blocked PAR-2-induced EGFR signaling cascade and cell growth. Finally, PAR-2 was detectable in both normal and GC specimens, but its expression was more pronounced in GC than controls and correlated with activated EGFR. These data show that PAR-2 is overexpressed in GC and suggest a role of PAR-2 in EGFR trans-activation and cell growth.
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Affiliation(s)
- Roberta Caruso
- Department of Internal Medicine and the Centre of Excellence for Genomic Risk Assessment in Multifactorial and Complex Diseases, University "Tor Vergata" of Rome, Rome, Italy
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