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Boi M, Demontis R, Isola M, Isola R, Loy F, Serra MP, Trucas M, Ekström J, Quartu M. The human major sublingual gland and its neuropeptidergic and nitrergic innervations. Ann Anat 2024; 255:152291. [PMID: 38821428 DOI: 10.1016/j.aanat.2024.152291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/18/2024] [Accepted: 05/27/2024] [Indexed: 06/02/2024]
Abstract
BACKGROUND What textbooks usually call the sublingual gland in humans is in reality a tissue mass of two types of salivary glands, the anteriorly located consisting of a cluster of minor sublingual glands and the posteriorly located major sublingual gland with its outlet via Bartholin's duct. Only recently, the adrenergic and cholinergic innervations of the major sublingual gland was reported, while information regarding the neuropeptidergic and nitrergic innervations is still lacking. METHODS Bioptic and autoptic specimens of the human major sublingual gland were examined by means of immunohistochemistry for the presence of vasoactive intestinal peptide (VIP)-, neuropeptide Y (NPY)-, substance P (SP)-, calcitonin gene related-peptide (CGRP)-, and neuronal nitric oxide synthase (nNOS)-labeled neuronal structures. RESULTS As to the neuropeptidergic innervation of secretory cells (here in the form of mucous tubular and seromucous cells), the findings showed many VIP-containing nerves, few NPY- and SP-containing nerves and a lack of CGRP-labeled nerves. As to the neuropeptidergic innervation of vessels, the number of VIP-containing nerves was modest, while, of the other neuropeptide-containing nerves under study, only few (SP and CGRP) to very few (NPY) nerves were observed. As to the nitrergic innervation, nNOS-containing nerves were very few close to secretory cells and even absent around vessels. CONCLUSION The various innervation patterns may suggest potential transmission mechanisms involved in secretory and vascular responses of the major sublingual gland.
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Affiliation(s)
- Marianna Boi
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Roberto Demontis
- Department of Medical Sciences and Public Health, University of Cagliari, Legal Medicine Division ARNAS Brotzu, Cagliari, Italy
| | - Michela Isola
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Raffaella Isola
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Francesco Loy
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Maria Pina Serra
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Marcello Trucas
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy
| | - Jörgen Ekström
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Medicinaregatan 13, Box 431, Göteborg 40530, Sweden
| | - Marina Quartu
- Department of Biomedical Sciences, Section of Cytomorphology, University of Cagliari, Cittadella Universitaria di Monserrato, Monserrato (CA) 09042, Italy.
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Innervation of the human minor salivary glands; immunohistochemical study for neurochemical substances. Tissue Cell 2022; 79:101934. [DOI: 10.1016/j.tice.2022.101934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 11/23/2022]
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Errachid A, Nohawica M, Wyganowska-Swiatkowska M. A comprehensive review of the influence of Epigallocatechin gallate on Sjögren's syndrome associated molecular regulators of exocytosis (Review). Biomed Rep 2021; 15:95. [PMID: 34631050 PMCID: PMC8493546 DOI: 10.3892/br.2021.1471] [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: 03/28/2021] [Accepted: 06/25/2021] [Indexed: 12/03/2022] Open
Abstract
Sjögren's syndrome (SS) is an autoimmune disorder that affects the salivary glands, leading to reduced secretory functions and oral and ocular dryness. The salivary glands are composed of acinar cells that are responsible for the secretion and production of secretory granules, which contain salivary components, such as amylase, mucins and immunoglobulins. This secretion process involves secretory vesicle trafficking, docking, priming and membrane fusion. A failure during any of the steps in exocytosis in the salivary glands results in the altered secretion of saliva. Soluble N-ethylmaleimide-sensitive-factor attachment protein receptors, actin, tight junctions and aquaporin 5 all serve an important role in the trafficking regulation of secretory vesicles in the secretion of saliva via exocytosis. Alterations in the expression and distribution of these selected proteins leads to salivary gland dysfunction, including SS. Several studies have demonstrated that green tea polyphenols, most notably Epigallocatechin gallate (EGCG), possess both anti-inflammatory and anti-apoptotic properties in normal human cells. Molecular, cellular and animal studies have indicated that EGCG can provide protective effects against autoimmune and inflammatory reactions in salivary glands in diseases such as SS. The aim of the present article is to provide a comprehensive and up-to-date review on the possible therapeutic interactions between EGCG and the selected molecular mechanisms associated with SS.
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Affiliation(s)
- Abdelmounaim Errachid
- Department of Dental Surgery and Periodontology, Poznan University of Medicinal Sciences, 60-812 Poznań, Greater Poland, Poland.,Earth and Life Institute, University Catholique of Louvain, B-1348 Louvain-la-Neuve, Ottignies-Louvain-la-Neuve, Belgium
| | - Michal Nohawica
- Department of Dental Surgery and Periodontology, Poznan University of Medicinal Sciences, 60-812 Poznań, Greater Poland, Poland
| | - Marzena Wyganowska-Swiatkowska
- Department of Dental Surgery and Periodontology, Poznan University of Medicinal Sciences, 60-812 Poznań, Greater Poland, Poland
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Chi C, Taylor KE, Quach H, Quach D, Criswell LA, Barcellos LF. Hypomethylation mediates genetic association with the major histocompatibility complex genes in Sjögren's syndrome. PLoS One 2021; 16:e0248429. [PMID: 33886574 PMCID: PMC8062105 DOI: 10.1371/journal.pone.0248429] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 02/25/2021] [Indexed: 12/22/2022] Open
Abstract
Differential methylation of immune genes has been a consistent theme observed in Sjögren's syndrome (SS) in CD4+ T cells, CD19+ B cells, whole blood, and labial salivary glands (LSGs). Multiple studies have found associations supporting genetic control of DNA methylation in SS, which in the absence of reverse causation, has positive implications for the potential of epigenetic therapy. However, a formal study of the causal relationship between genetic variation, DNA methylation, and disease status is lacking. We performed a causal mediation analysis of DNA methylation as a mediator of nearby genetic association with SS using LSGs and genotype data collected from 131 female members of the Sjögren's International Collaborative Clinical Alliance registry, comprising of 64 SS cases and 67 non-cases. Bumphunter was used to first identify differentially-methylated regions (DMRs), then the causal inference test (CIT) was applied to identify DMRs mediating the association of nearby methylation quantitative trait loci (MeQTL) with SS. Bumphunter discovered 215 DMRs, with the majority located in the major histocompatibility complex (MHC) on chromosome 6p21.3. Consistent with previous findings, regions hypomethylated in SS cases were enriched for gene sets associated with immune processes. Using the CIT, we observed a total of 19 DMR-MeQTL pairs that exhibited strong evidence for a causal mediation relationship. Close to half of these DMRs reside in the MHC and their corresponding meQTLs are in the region spanning the HLA-DQA1, HLA-DQB1, and HLA-DQA2 loci. The risk of SS conferred by these corresponding MeQTLs in the MHC was further substantiated by previous genome-wide association study results, with modest evidence for independent effects. By validating the presence of causal mediation, our findings suggest both genetic and epigenetic factors contribute to disease susceptibility, and inform the development of targeted epigenetic modification as a therapeutic approach for SS.
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Affiliation(s)
- Calvin Chi
- Center for Computational Biology, College of Engineering, University of California, Berkeley, Berkeley, California, United States of America
- Genetic Epidemiology and Genomics Laboratory, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Kimberly E. Taylor
- Department of Medicine, Russell/Engleman Rheumatology Research Center, University of California, San Francisco, San Francisco, California, United States of America
| | - Hong Quach
- Genetic Epidemiology and Genomics Laboratory, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Diana Quach
- Genetic Epidemiology and Genomics Laboratory, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
| | - Lindsey A. Criswell
- Department of Medicine, Russell/Engleman Rheumatology Research Center, University of California, San Francisco, San Francisco, California, United States of America
| | - Lisa F. Barcellos
- Center for Computational Biology, College of Engineering, University of California, Berkeley, Berkeley, California, United States of America
- Genetic Epidemiology and Genomics Laboratory, School of Public Health, University of California, Berkeley, Berkeley, California, United States of America
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5
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Abstract
AbstractPituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide with widespread occurrence and diverse functions. PACAP binds to specific PAC1 and non-specific VPAC1/2 receptors. PACAP is considered as a growth factor, as it plays important roles during development and participates in reparative processes. Highest concentrations are found in the nervous system and endocrine glands, where several functions are known, including actions in tissue growth, differentiation and tumour development. Therefore, we have investigated expression of PACAP and its receptors in different tumours, including those of endocrine glands. We showed earlier that PACAP and PAC1 receptor staining intensity decreased in pancreatic ductal adenocarcinoma. In the present study we aimed to investigate alterations of PACAP and PAC1 receptor in human insulinoma and compared the immunostaining pattern with samples from chronic pancreatitis patients. We collected perioperative and histological data of patients who underwent operation because of insulinoma or chronic pancreatitis over a five-year-long period. Histology showed chronic pancreatitis with severe scar formation in pancreatitis patients, while tumour samples evidenced Grade 1 or 2 insulinoma. PACAP and PAC1 receptor expression was studied using immunohistochemistry. Staining intensity was very strong in the Langerhans islets of normal tissue and discernible staining was also observed in the exocrine pancreas. Immunostaining intensity for both PACAP and PAC1 receptor was markedly weaker in insulinoma samples, and disappeared from chronic pancreatitis samples except for intact islets. These findings show that PAC1 receptor/PACAP signalling is altered in insulinoma and this suggests a possible involvement of this system in tumour growth or differentiation.
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Culp DJ, Zhang Z, Evans RL. VIP and muscarinic synergistic mucin secretion by salivary mucous cells is mediated by enhanced PKC activity via VIP-induced release of an intracellular Ca 2+ pool. Pflugers Arch 2020; 472:385-403. [PMID: 31932898 DOI: 10.1007/s00424-020-02348-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/09/2019] [Accepted: 01/06/2020] [Indexed: 12/12/2022]
Abstract
Mucin secretion by salivary mucous glands is mediated predominantly by parasympathetic acetylcholine activation of cholinergic muscarinic receptors via increased intracellular free calcium ([Ca2+]i) and activation of conventional protein kinase C isozymes (cPKC). However, the parasympathetic co-neurotransmitter, vasoactive intestinal peptide (VIP), also initiates secretion, but to a lesser extent. In the present study, cross talk between VIP- and muscarinic-induced mucin secretion was investigated using isolated rat sublingual tubuloacini. VIP-induced secretion is mediated by cAMP-activated protein kinase A (PKA), independently of increased [Ca2+]i. Synergistic secretion between VIP and the muscarinic agonist, carbachol, was demonstrated but only with submaximal carbachol. Carbachol has no effect on cAMP ± VIP. Instead, PKA activated by VIP releases Ca2+ from an intracellular pool maintained by the sarco/endoplasmic reticulum Ca2+-ATPase pump. Calcium release was independent of phospholipase C activity. The resultant sustained [Ca2+]i increase is additive to submaximal, but not maximal carbachol-induced [Ca2+]i. Synergistic mucin secretion was mimicked by VIP plus either phorbol 12-myristate 13-acetate or 0.01 μM thapsigargin, and blocked by the PKC inhibitor, Gö6976. VIP-induced Ca2+ release also promoted store-operated Ca2+ entry. Synergism is therefore driven by VIP-mediated [Ca2+]i augmenting cPKC activity to enhance muscarinic mucin secretion. Additional data suggest ryanodine receptors control VIP/PKA-mediated Ca2+ release from a Ca2+ pool also responsive to maximal carbachol. A working model of muscarinic and VIP control of mucous cell exocrine secretion is presented. Results are discussed in relation to synergistic mechanisms in other secretory cells, and the physiological and therapeutic significance of VIP/muscarinic synergism controlling salivary mucous cell exocrine secretion.
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Affiliation(s)
- David J Culp
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA. .,Department of Oral Biology, UF College of Dentistry, P.O. Box 100424, Gainesville, FL, 32610-3003, USA.
| | - Z Zhang
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA
| | - R L Evans
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA.,Unilever Research & Development, Port Sunlight Laboratory, Quarry Road East, Bebington, Wirral, CH63 3JW, UK
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7
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Ferencz S, Reglodi D, Kaszas B, Bardosi A, Toth D, Vekony Z, Vicena V, Karadi O, Kelemen D. PACAP and PAC1 receptor expression in pancreatic ductal carcinoma. Oncol Lett 2019; 18:5725-5730. [PMID: 31788045 PMCID: PMC6865831 DOI: 10.3892/ol.2019.10971] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 06/12/2019] [Indexed: 12/26/2022] Open
Abstract
Pancreatic carcinoma is one of the most malignant diseases and is associated with a poor survival rate. Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide that acts on three different G protein-coupled receptors: the specific PAC1 and the VPAC1/2 that also bind vasoactive intestinal peptide. PACAP is widely distributed in the body and has diverse physiological effects. Among other things, it acts as a trophic factor and influences proliferation and differentiation of several different cells both under normal circumstances and tumourous transformation. Changes of PACAP and its receptors have been shown in various tumour types. However, it is not known whether PACAP and its specific receptor are altered in pancreatic cancer. Perioperative data of patients with pancreas carcinoma was investigated over a five-year period. Histological results showed Grade 2 or Grade 3 adenocarcinoma in most cases. PACAP and PAC1 receptor expression were investigated by immunohistochemistry. Staining intensity of PAC1 receptor was strong in normal tissues both in the exocrine and endocrine parts of the pancreas, the receptor staining was markedly weaker in the adenocarcinoma. PACAP immunostaining was weak in the exocrine part and very strong in the islets and nerve elements in non-tumourous tissues. The PACAP immunostaining almost disappeared in the adenocarcinoma samples. Based on these findings a decrease or lack of the PAC1 receptor/PACAP signalling might have an influence on tumour growth and/or differentiation.
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Affiliation(s)
- Sandor Ferencz
- Department of Surgery, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Dora Reglodi
- Department of Anatomy, MTA-PTE PACAP Research Group, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Balint Kaszas
- Department of Pathology, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Attila Bardosi
- Center for Histology, Cytology and Molecular Diagnostics, and Proteopath GmbH, Trier 54296, Germany
| | - Denes Toth
- Department of Forensic Medicine, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Zsofia Vekony
- Department of Surgery, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Viktoria Vicena
- Department of Anatomy, MTA-PTE PACAP Research Group, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Oszkar Karadi
- Department of Oncology, University of Pécs, Medical School, Pécs 7622, Hungary
| | - Dezso Kelemen
- Department of Surgery, University of Pécs, Medical School, Pécs 7622, Hungary
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8
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Asam S, Neag G, Berardicurti O, Gardner D, Barone F. The role of stroma and epithelial cells in primary Sjögren's syndrome. Rheumatology (Oxford) 2019; 60:3503-3512. [PMID: 30945742 DOI: 10.1093/rheumatology/kez050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/19/2018] [Indexed: 12/27/2022] Open
Abstract
Primary SS (pSS) is a chronic autoimmune condition characterized by infiltration of the exocrine glands and systemic B cell hyperactivation. This glandular infiltration is associated with loss of glandular function, with pSS patients primarily presenting with severe dryness of the eyes and mouth. Within the affected glands, the infiltrating lymphocytes are organized in tertiary lymphoid structures. Tertiary lymphoid structures subvert normal tissue architecture and impact on organ function, by promoting the activation and maintenance of autoreactive lymphocytes. This review summarizes the current knowledge about the role of stromal cells (including endothelium, epithelium, nerves and fibroblasts) in the pathogenesis of pSS, in particular the interactions taking place between stromal cells and infiltrating lymphocytes. We will provide evidences pointing towards the driving role of stromal cells in the orchestration of the local inflammatory milieu, thus highlighting the need for therapies aimed at targeting this compartment alongside classical immunosuppression in pSS.
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Affiliation(s)
- Saba Asam
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Georgiana Neag
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | | | - David Gardner
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Francesca Barone
- Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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Pedersen AML, Sørensen CE, Proctor GB, Carpenter GH, Ekström J. Salivary secretion in health and disease. J Oral Rehabil 2018; 45:730-746. [PMID: 29878444 DOI: 10.1111/joor.12664] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2018] [Indexed: 12/16/2022]
Abstract
Saliva is a complex fluid produced by 3 pairs of major salivary glands and by hundreds of minor salivary glands. It comprises a large variety of constituents and physicochemical properties, which are important for the maintenance of oral health. Saliva not only protects the teeth and the oropharyngeal mucosa, it also facilitates articulation of speech, and is imperative for mastication and swallowing. Furthermore, saliva plays an important role in maintaining a balanced microbiota. Thus, the multiple functions provided by saliva are essential for proper protection and functioning of the body as a whole and for the general health. A large number of diseases and medications can affect salivary secretion through different mechanisms, leading to salivary gland dysfunction and associated oral problems, including xerostomia, dental caries and fungal infections. The first part of this review article provides an updated insight into our understanding of salivary gland structure, the neural regulation of salivary gland secretion, the mechanisms underlying the formation of saliva, the various functions of saliva and factors that influence salivary secretion under normal physiological conditions. The second part focuses on how various diseases and medical treatment including commonly prescribed medications and cancer therapies can affect salivary gland structure and function. We also provide a brief insight into how to diagnose salivary gland dysfunction.
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Affiliation(s)
- A M L Pedersen
- Oral Medicine, Oral Pathology & Clinical Oral Physiology, University of Copenhagen, Copenhagen, Denmark
| | - C E Sørensen
- Oral Biochemistry, Cariology & Endodontics, Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - G B Proctor
- Mucosal & Salivary Biology Division, King's College London Dental Institute, London, UK
| | - G H Carpenter
- Mucosal & Salivary Biology Division, King's College London Dental Institute, London, UK
| | - J Ekström
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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10
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Insight into pathogenesis of Sjögren's syndrome: Dissection on autoimmune infiltrates and epithelial cells. Clin Immunol 2017; 182:30-40. [PMID: 28330683 DOI: 10.1016/j.clim.2017.03.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/17/2017] [Accepted: 03/17/2017] [Indexed: 12/11/2022]
Abstract
Sjögren's syndrome (SS) is a chronic autoimmune disease with broad clinical spectrum, extending from benign exocrinopathy to severe systemic disease and lymphoma development. The glandular and extraglandular dysfunction of SS is associated with lymphocytic infiltrates that invade the epithelial structures of affected organs. The in-depth study of autoimmune lesions in the minor salivary glands (MSG), which are the major target-organ of SS responses, revealed that the lymphocytic infiltrates vary in severity and composition among SS-patients, are full-blown at diagnosis and remain unchanged thereafter. Although the pathogenetic pathways underlying SS have not yet elucidated, it is well-established that glandular epithelial cells are central regulators of local autoimmune responses. Moreover, chronic inflammation affects epithelial function and phenotype, which strengthens or weakens their immunoregulatory/secretory function, leading to deterioration of autoimmune phenomena. Herein, the current findings regarding the autoimmune lesions, the role of epithelial cells and their interaction with infiltrating lymphocytic cells are discussed.
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11
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Cardoso AM, Schetinger MRC, Correia-de-Sá P, Sévigny J. Impact of ectonucleotidases in autonomic nervous functions. Auton Neurosci 2015; 191:25-38. [PMID: 26008223 DOI: 10.1016/j.autneu.2015.04.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 04/28/2015] [Accepted: 04/29/2015] [Indexed: 01/05/2023]
Abstract
Adenine and uracil nucleotides play key functions in the autonomic nervous system (ANS). For instance, ATP acts as a neurotransmitter, co-transmitter and neuromodulator in the ANS. The purinergic system encompasses (1) receptors that respond to extracellular purines, which are designated as P1 and P2 purinoceptors, (2) purine release and uptake, and (3) a cascade of enzymes that regulate the concentration of purines near the cell surface. Ectonucleotidases and adenosine deaminase (ADA) are enzymes responsible for the hydrolysis of ATP (and other nucleotides such as ADP, UTP, UDP, AMP) and adenosine, respectively. Accordingly, these enzymes are expected to play an important role in the control of neuro-effector transmission in tissues innervated by both the sympathetic and parasympathetic divisions of the ANS. Indeed, ectonucleotidases have the ability to either terminate P2 receptor responses initiated by nucleoside triphosphates (ATP and UTP), and/or to favor the activation of ADP (e.g. P2Y1,12,13) and UDP (e.g. P2Y6) and/or adenosine (P1) specific receptors. In addition, ectonucleotidases can also importantly protect some P2 receptors from desensitization (e.g. P2X1, P2Y1). In this review, we present the (putative) roles of ectonucleotidases and ADA in the ANS with a focus on their regulatory activity at neuro-effector junctions in the following tissues: heart, vas deferens, urinary bladder, salivary glands, blood vessels and the intestine. We also present their implication in nociceptive transmission.
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Affiliation(s)
- Andréia Machado Cardoso
- Post-Graduation Program in Toxicological Biochemistry, Department of Biochemistry and Molecular Biology of the Center of Natural and Exact Sciences of the Federal University of Santa Maria, Santa Maria Rio Grande do Sul, Brazil; Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada; Centre de Recherche du CHU de Québec - Université Laval, Québec G1V 4G2, Canada.
| | - Maria Rosa Chitolina Schetinger
- Post-Graduation Program in Toxicological Biochemistry, Department of Biochemistry and Molecular Biology of the Center of Natural and Exact Sciences of the Federal University of Santa Maria, Santa Maria Rio Grande do Sul, Brazil
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia, MedInUP, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal
| | - Jean Sévigny
- Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada; Centre de Recherche du CHU de Québec - Université Laval, Québec G1V 4G2, Canada.
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12
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Enger TB, Aure MH, Jensen JL, Galtung HK. Calcium signaling and cell volume regulation are altered in Sjögren's Syndrome. Acta Odontol Scand 2014; 72:549-56. [PMID: 24471729 DOI: 10.3109/00016357.2013.879995] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Sjögren's Syndrome (SS) is a chronic autoimmune disease, leading to deficient secretion from salivary and lacrimal glands. Saliva production is normally increased by cholinergic innervation, giving rise to intracellular calcium signaling and water transport through water channels (aquaporins, AQPs). The aim of this study was to investigate possible pathophysiological changes in cell volume regulation, AQP expression and localization, and intracellular calcium signaling in glandular cells from SS patients compared to controls. MATERIALS AND METHODS A total of 35 SS patients and 41 non-SS controls were included. Real time qPCR was combined with immunohistochemistry to analyze the mRNA expression and cellular distribution of AQP1, 3 and 5. Cell volume regulation and intracellular calcium signaling were examined in fresh acinar cells. RESULTS We show for the first time a reduced mRNA expression of AQP1 and 5 in SS compared to controls, accompanied by a decrease in staining intensity of AQP1, 3 and 5 in areas adjacent to local lymphocytic infiltration. Furthermore, we observed that the SS cells' capacity for volume regulation was abnormal. Similarly, the calcium response after parasympathetic agonist (carbachol) stimulation was markedly decreased in SS cells. CONCLUSIONS It is concluded that mRNA expression of AQP1 and 5, protein distribution of AQP1, 3 and 5, glandular cell volume regulation and intracellular calcium signaling are all altered in SS, pointing to possible pathophysiological mechanisms in SS.
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13
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Del Fiacco M, Quartu M, Ekström J, Melis T, Boi M, Isola M, Loy F, Serra MP. Effect of the neuropeptides vasoactive intestinal peptide, peptide histidine methionine and substance P on human major salivary gland secretion. Oral Dis 2014; 21:216-23. [PMID: 24725136 DOI: 10.1111/odi.12249] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 03/19/2014] [Accepted: 03/31/2014] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The parasympathetic transmitters vasoactive intestinal peptide (VIP) and substance P (SP) are secretagogues in salivary glands of animals. Currently, we hypothesise that in human salivary glands, these neuropeptides and the VIP-related peptide histidine methionine (PHM) also exert secretory actions, reflected morphologically by exocytosis of acinar protein/glycoprotein-storing granules. MATERIALS AND METHODS Submandibular and parotid gland tissues, exposed in vitro to VIP and PHM, and SP, respectively, were examined by light and transmission electron microscopy. For comparison, the response to in vitro stimulation of isoproterenol, phenylephrine and carbachol was examined. Moreover, the peptidergic innervation of the glands was examined by immunohistochemistry. RESULTS Vasoactive intestinal peptide- and PHM-immunoreactive nerves were in close proximity to acini and ducts in the two glands, while these elements lacked a SP-positive innervation. While no morphological changes occurred in response to SP (parotid glands), VIP and PHM administration (submandibular glands) caused conspicuous acinar degranulation accompanied by luminal space broadening. In the two glands, both α1 - and β-adrenergic receptor stimulation and muscarinic receptor stimulation caused similar changes as to VIP/PHM, although to varying extent. CONCLUSIONS Vasoactive intestinal peptide and PHM, but not SP, are likely transmitters in the parasympathetic control of salivary (protein) secretion in humans.
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Affiliation(s)
- M Del Fiacco
- Section of Cytomorphology, Department of Biomedicals Sciences, University of Cagliari, Cagliari, Italy
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Burnstock G. Purinergic signalling in the gastrointestinal tract and related organs in health and disease. Purinergic Signal 2014; 10:3-50. [PMID: 24307520 PMCID: PMC3944042 DOI: 10.1007/s11302-013-9397-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/24/2013] [Indexed: 01/04/2023] Open
Abstract
Purinergic signalling plays major roles in the physiology and pathophysiology of digestive organs. Adenosine 5'-triphosphate (ATP), together with nitric oxide and vasoactive intestinal peptide, is a cotransmitter in non-adrenergic, non-cholinergic inhibitory neuromuscular transmission. P2X and P2Y receptors are widely expressed in myenteric and submucous enteric plexuses and participate in sympathetic transmission and neuromodulation involved in enteric reflex activities, as well as influencing gastric and intestinal epithelial secretion and vascular activities. Involvement of purinergic signalling has been identified in a variety of diseases, including inflammatory bowel disease, ischaemia, diabetes and cancer. Purinergic mechanosensory transduction forms the basis of enteric nociception, where ATP released from mucosal epithelial cells by distension activates nociceptive subepithelial primary afferent sensory fibres expressing P2X3 receptors to send messages to the pain centres in the central nervous system via interneurons in the spinal cord. Purinergic signalling is also involved in salivary gland and bile duct secretion.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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15
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Castro I, Sepúlveda D, Cortés J, Quest A, Barrera M, Bahamondes V, Aguilera S, Urzúa U, Alliende C, Molina C, González S, Hermoso M, Leyton C, González M. Oral dryness in Sjögren's syndrome patients. Not just a question of water. Autoimmun Rev 2013. [DOI: 10.1016/j.autrev.2012.10.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Juusela P, Tanskanen M, Nieminen A, Kari K, Suominen L, Uitto VJ, Kiuru-Enari S. Xerostomia in hereditary gelsolin amyloidosis. Amyloid 2013; 20:39-44. [PMID: 23356404 DOI: 10.3109/13506129.2013.764284] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hereditary gelsolin amyloidosis (AGel amyloidosis) is a rare, dominantly inherited systemic disease with worldwide distribution, caused by c.654G > A or c.654G > T gelsolin gene mutation. The disease mainly manifests with late-onset dystrophy of the cornea, laxity of the skin and dysfunction of the cranial nerves whereas the oral manifestations have remained less-studied. To examine if AGel amyloidosis also affects salivary gland function, we studied 27 patients. In a questionnaire, 89% of them reported oral dryness, and 74% oral and ocular dryness. Unstimulated (UWS) and stimulated whole salivary flow (SWS) rates were measured, and salivary proteins were analyzed in the patients and controls. Hyposalivation according to UWS was detected in 67% of the patients, while decreased SWS occurred in 63% of the patients and 19% of the controls (p = 0.001). The secretion rates of salivary total protein and IgA were significantly lower in patients than controls. Histopathological analyses of labial salivary gland biopsies showed deposition of gelsolin amyloid, atrophy and inflammation. This study showed that AGel amyloidosis belongs to the differential diagnostic choices to be kept in mind in the patients presenting with xerostomia, low secretion rates of salivary total protein and IgA and/or deposition of amyloid in the minor salivary glands. AGel amyloidosis patients should be advised for efficient dental care.
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Affiliation(s)
- Pirjo Juusela
- Department of Oral Biology, Institute of Dentistry, University of Helsinki, Helsinki, Finland.
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17
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Barrera MJ, Sánchez M, Aguilera S, Alliende C, Bahamondes V, Molina C, Quest AF, Urzúa U, Castro I, González S, Sung HH, Albornoz A, Hermoso M, Leyton C, González MJ. Aberrant localization of fusion receptors involved in regulated exocytosis in salivary glands of Sjögren’s syndrome patients is linked to ectopic mucin secretion. J Autoimmun 2012; 39:83-92. [DOI: 10.1016/j.jaut.2012.01.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 01/07/2012] [Indexed: 02/01/2023]
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Dysfunction of lacrimal and salivary glands in Sjögren's syndrome: nonimmunologic injury in preinflammatory phase and mouse model. J Biomed Biotechnol 2011; 2011:407031. [PMID: 21660135 PMCID: PMC3110304 DOI: 10.1155/2011/407031] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 02/08/2011] [Accepted: 03/08/2011] [Indexed: 11/30/2022] Open
Abstract
Sjögren's syndrome (SjS) is a chronic autoimmune disorder characterized by dry eyes and dry mouth due to dacryoadenitis and sialoadenitis with SS-A/Ro and/or SS-B/La autoantibodies in genetically predisposed individuals. Destruction of lacrimal and salivary glands by autoimmune reactions may lead to clinical manifestation. However, the mechanisms behind the decreased volume of secretions in tears and saliva are complex and are not fully understood. Exocrine gland dysfunction may precede autoimmunity (acquired immunity) or represent a process independent from inflammation in the pathogenesis of SjS. The preceded functional and morphologic changes of those tissues by nonimmunologic injury before the development of inflammation at the sites of target organs have been implicated. This paper focuses on the several factors and components relating to glandular dysfunction and morphologic changes by nonimmunologic injury during the preinflammatory phase in mouse model, including the factors which link between innate immunity and adaptive immunity.
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19
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Fox RL, Stern M. Sjögren's syndrome: mechanisms ofpathogenesis involve interaction of immune and neurosecretory systems. Scand J Rheumatol 2010. [DOI: 10.1080/0300974023208178882] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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20
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Berggreen E, Nyløkken K, Delaleu N, Hajdaragic-Ibricevic H, Jonsson MV. Impaired vascular responses to parasympathetic nerve stimulation and muscarinic receptor activation in the submandibular gland in nonobese diabetic mice. Arthritis Res Ther 2009; 11:R18. [PMID: 19200376 PMCID: PMC2688250 DOI: 10.1186/ar2609] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Revised: 01/22/2009] [Accepted: 02/06/2009] [Indexed: 12/02/2022] Open
Abstract
Introduction Decreased vascular responses to salivary gland stimulation are observed in Sjögren's syndrome patients. We investigate whether impaired vascular responses to parasympathetic stimulation and muscarinic receptor activation in salivary glands parallels hyposalivation in an experimental model for Sjögren's syndrome. Methods Blood flow responses in the salivary glands were measured by laser Doppler flowmeter. Muscarinic receptor activation was followed by saliva secretion measurements. Nitric oxide synthesis-mediated blood flow responses were studied after administration of a nitric oxide synthase inhibitor. Glandular autonomic nerves and muscarinic 3 receptor distributions were also investigated. Results Maximal blood flow responses to parasympathetic stimulation and muscarinic receptor activation were significantly lower in nonobese diabetic (NOD) mice compared with BALB/c mice, coinciding with impaired saliva secretion in nonobese diabetic mice (P < 0.005). Nitric oxide synthase inhibitor had less effect on blood flow responses after parasympathetic nerve stimulation in nonobese diabetic mice compared with BALB/c mice (P < 0.02). In nonobese diabetic mice, salivary gland parasympathetic nerve fibres were absent in areas of focal infiltrates. Muscarinic 3 receptor might be localized in the blood vessel walls of salivary glands. Conclusions Impaired vasodilatation in response to parasympathetic nerve stimulation and muscarinic receptor activation may contribute to hyposalivation observed in nonobese diabetic mice. Reduced nitric oxide signalling after parasympathetic nerve stimulation may contribute in part to the impaired blood flow responses. The possibility of muscarinic 3 receptor in the vasculature supports the notion that muscarinic 3 receptor autoantibodies present in nonobese diabetic mice might impair the fluid transport required for salivation. Parasympathetic nerves were absent in areas of focal infiltrates, whereas a normal distribution was found within glandular epithelium. Trial registration The trial registration number for the present study is 79-04/BBB, given by the Norwegian State Commission for Laboratory Animals.
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Affiliation(s)
- Ellen Berggreen
- Department of Biomedicine, Jonas Liesvei 91, Bergen 5009, Norway.
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21
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Gaal V, Mark L, Kiss P, Kustos I, Tamas A, Kocsis B, Lubics A, Nemeth V, Nemeth A, Lujber L, Pytel J, Toth G, Reglodi D. Investigation of the effects of PACAP on the composition of tear and endolymph proteins. J Mol Neurosci 2008; 36:321-9. [PMID: 18421426 DOI: 10.1007/s12031-008-9067-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Accepted: 03/12/2008] [Indexed: 12/30/2022]
Abstract
Pituitary adenylate cyclase activating polypeptide (PACAP) is widely distributed in ocular tissues, including the lacrimal gland. PACAP has been shown to influence the activity of several exocrine glands, but its effects on the composition of the tear film are not known yet. Similarly, the presence of PACAP has already been shown in the inner ear, but it is not known whether PACAP influences the composition of the endolymph. The aim of the present study was to investigate whether systemic injection of PACAP has any modulatory effects on the protein composition of the tear film and endolymph using chip electrophoresis and mass spectrometry analysis. Tear and endolymph samples were collected from rats and chickens, respectively, at various time points after systemic injection of PACAP. Fluid samples were further processed for chip electrophoretic studies. No difference was found in the protein composition of the endolymph between control and PACAP-treated animals. In contrast, tear samples showed a marked difference after PACAP treatment. Proteins in the molecular range 50-70 kDa, which showed a different chip electropherogram profile in every PACAP-treated sample, were further analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. PACAP treatment induced a repression in certain keratins, while others were induced after PACAP injection. Furthermore, PACAP treatment decreased aldehyde dehydrogenase expression. The present study provides a base for further studies on the in vivo effects of PACAP on the composition of tear film. These investigations may have important clinical relevance because of the noninvasive sample collection, the correlation between tear proteins and ocular diseases, and the possible presence of biomarkers for both ophthalmological and systemic pathological conditions.
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Affiliation(s)
- Valeria Gaal
- Department of Ophthalmology, University of Pecs, Ifjusag u 13, 7624, Pecs, Hungary
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23
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Carpenter GH, Osailan SM, Correia P, Paterson KP, Proctor GB. Rat salivary gland ligation causes reversible secretory hypofunction. Acta Physiol (Oxf) 2007; 189:241-9. [PMID: 17305704 PMCID: PMC1859985 DOI: 10.1111/j.1365-201x.2006.01662.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM To determine the influence of inflammation on salivary secretion. Secretion by salivary glands involves interactions between nerves, blood vessels and salivary cells. The present study investigated the effects of inflammation on rat submandibular gland function following acute ductal obstruction. METHODS Under recovery anaesthesia a metal clip was placed on the main duct of the submandibular gland. After 24 h salivary secretion was evoked by nerve and methacholine stimulation. For recovery experiments the clip was removed after 24 h and the animal left to recover for 3 days when salivary function was again assessed. RESULTS By 24 h of obstruction an inflammatory infiltrate had developed within the obstructed gland and stimulated salivary flows were just 20% of the normal secretion, whilst protein secretion and ion reabsorption were also severely impaired. If ductal obstruction was removed after 24 h the salivary function returned to normal after 3 days of recovery. In vitro analysis of cells from 24-h ligated glands revealed normal changes in intracellular calcium (the main secondary messenger involved in fluid secretion) in response to methacholine stimulation. Protein secretion from isolated cells indicated some changes in particular to methacholine-induced protein secretion although a significant protein secretion was still seen in response to isoprenaline - the main stimulus for protein secretion. CONCLUSION This report demonstrates reversible salivary inhibition associated with an inflammatory infiltrate within the salivary gland.
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Affiliation(s)
- G H Carpenter
- Salivary Research Unit, Floor 17, Guy's Tower, King's College London, London, UK.
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Proctor GB, Carpenter GH. Regulation of salivary gland function by autonomic nerves. Auton Neurosci 2006; 133:3-18. [PMID: 17157080 DOI: 10.1016/j.autneu.2006.10.006] [Citation(s) in RCA: 458] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 10/06/2006] [Accepted: 10/20/2006] [Indexed: 11/24/2022]
Abstract
Oral homeostasis is dependent upon saliva and its content of proteins. Reflex salivary flow occurs at a low 'resting' rate and for short periods of the day more intense taste or chewing stimuli evoke up to ten fold increases in salivation. The secretion of salivary fluid and proteins is controlled by autonomic nerves. All salivary glands are supplied by cholinergic parasympathetic nerves which release acetylcholine that binds to M3 and (to a lesser extent) M1 muscarinic receptors, evoking the secretion of saliva by acinar cells in the endpieces of the salivary gland ductal tree. Most salivary glands also receive a variable innervation from sympathetic nerves which released noradrenaline from which tends to evoke greater release of stored proteins, mostly from acinar cells but also ductal cells. There is some 'cross-talk' between the calcium and cyclic AMP intracellular pathways coupling autonomic stimulation to secretion and salivary protein secretion is augmented during combined stimulation. Other non-adrenergic, non-cholinergic neuropeptides released from autonomic nerves evoke salivary gland secretion and parasympathetically derived vasointestinal peptide, acting through endothelial cell derived nitric oxide, plays a role in the reflex vasodilatation that accompanies secretion. Neuronal type, calcium-activated, soluble nitric oxide within salivary cells appears to play a role in mediating salivary protein secretion in response to autonomimetics. Fluid secretion by salivary glands involves aquaporin 5 and the extent to which the expression of aquaporin 5 on apical acinar cell membranes is upregulated by cholinomimetics remains uncertain. Extended periods of autonomic denervation, liquid diet feeding (reduced reflex stimulation) or duct ligation cause salivary gland atrophy. The latter two are reversible, demonstrating that glands can regenerate provided that the autonomic innervation remains intact. The mechanisms by which nerves integrate with salivary cells during regeneration or during salivary gland development remain to be elucidated.
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Affiliation(s)
- Gordon B Proctor
- Salivary Research Unit, King's College London Dental Institute, Floor 17 Guy's Tower, London SE1 9RT, UK.
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25
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Dawson LJ, Fox PC, Smith PM. Sjögrens syndrome—the non-apoptotic model of glandular hypofunction. Rheumatology (Oxford) 2006; 45:792-8. [PMID: 16595520 DOI: 10.1093/rheumatology/kel067] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- L J Dawson
- Oral Surgery, University of Liverpool Dental School, Room 1.10, Edwards Building, Daulby Street, Liverpool L69 3GN, UK.
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26
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Uğar-Cankal D, Ozmeric N. A multifaceted molecule, nitric oxide in oral and periodontal diseases. Clin Chim Acta 2006; 366:90-100. [PMID: 16387291 DOI: 10.1016/j.cca.2005.10.018] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 10/19/2005] [Accepted: 10/20/2005] [Indexed: 11/28/2022]
Abstract
Nitric oxide (NO) is a molecule with multiple effects on different tissues. NO takes important roles in vasodilatation, bacterial challenge and cytokine stimulation, regulation of mineralized tissue function, neurotransmission, and platelet aggregation, etc. However, under pathological conditions, NO has damaging effects. NO is synthesized by NO synthases (NOS) and inducible isoform of NOS (iNOS) is closely related to the pathophysiological characteristics of inflammatory diseases such as periodontal diseases. The expression of iNOS has been investigated in salivary gland-related diseases, temporomandibular joint disorders and oral cancer as well. The beneficial and damaging effects of NO in diseases related with periodontal, dental and maxillofacial area are discussed in this review. The biological pathways involved with NO and NO inhibitors may be good drug targets to have a role in the future management of patients with diseases in orofacial region.
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Affiliation(s)
- Dilek Uğar-Cankal
- Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Gazi University, Biskek caddesi 84.sokak 06510 Emek, Ankara, Turkey.
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Soinila J, Nuorva K, Soinila S. Nitric oxide synthase in human salivary glands. Histochem Cell Biol 2005; 125:717-23. [PMID: 16341869 DOI: 10.1007/s00418-005-0123-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2005] [Indexed: 10/25/2022]
Abstract
The distribution of the three nitric oxide synthase (NOS) isoforms was determined immunohistochemically in the human minor and major salivary glands with comparison to that of rat salivary glands. In contrast to rat glands, which contained a dense plexus of neuronal NOS-immunoreactive nerve fibers, only a minority of the nerve fibers in human glands showed neuronal NOS immunoreactivity. Human labial and submandibular glands contained sparse NOS-immunoreactive fibers, while only occasional nerve fibers in the parotid or sublingual glands were stained. Furthermore, in contrast to the animal glands, most duct epithelial cells in all human salivary glands were immunoreactive for neuronal NOS. No specific immunoreactivity for inducible or endothelial NOS were observed in the nerve fibers or duct epithelium. We provide evidence to suggest that the role of nitric oxide in the regulation of salivary gland function is different in human as compared to experimental animals. Nitricergic innervation in human tissue is very sparse and thus nitric oxide is probably of minor importance as a neural regulator of salivary glands. Instead, NOS localized in duct epithelial cells suggests that nitric oxide might directly regulate saliva secretion and it is a putative source of nitrates previously reportedly secreted into the saliva.
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Affiliation(s)
- Jouni Soinila
- Department of Oral and Maxillofacial Surgery, Central Hospital of Central Finland, 40620, Jyväskylä, Finland.
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28
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Zoukhri D. Effect of inflammation on lacrimal gland function. Exp Eye Res 2005; 82:885-98. [PMID: 16309672 PMCID: PMC1361268 DOI: 10.1016/j.exer.2005.10.018] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Revised: 10/06/2005] [Accepted: 10/17/2005] [Indexed: 12/21/2022]
Abstract
The lacrimal gland is the main contributor to the aqueous layer of the tear film. It secretes proteins, electrolytes and water, which helps to nourish and protect the ocular surface. Lacrimal gland secretion is primarily under neural control, which is achieved through a neural reflex arc. Stimuli to the ocular surface activate afferent sensory nerves in the cornea and conjunctiva. This in turn activates efferent parasympathetic and sympathetic nerves in the lacrimal gland to stimulate secretion. Sex steroid hormones are also important regulators of lacrimal gland functions. A decrease or lack of lacrimal gland secretion is the leading cause of aqueous tear deficient dry eye syndrome (DES). It has been suggested that DES is an inflammatory disorder that affects the ocular surface and the lacrimal gland. In several pathological instances, the lacrimal gland can become a target of the immune system and show signs of inflammation. This can result from autoimmune diseases (Sjögren's syndrome), organ transplantation (graft versus host disease), or simply as a result of aging. The hallmarks of lacrimal gland inflammation are the presence of focal lymphocytic infiltrates and increased production of proinflammatory cytokines. The mechanisms leading to lacrimal gland dysfunction are still poorly understood. Apoptosis, production of autoantibodies, hormonal imbalance, alterations in signaling molecules, neural dysfunction, and increased levels of proinflammatory cytokines have been proposed as possible mediators of lacrimal gland insufficiency in disease states.
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Affiliation(s)
- Driss Zoukhri
- Department of General Dentistry, Tufts University School of Dental Medicine, Boston, MA, USA.
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Lodde BM, Mineshiba F, Wang J, Cotrim AP, Afione S, Tak PP, Baum BJ. Effect of human vasoactive intestinal peptide gene transfer in a murine model of Sjogren's syndrome. Ann Rheum Dis 2005; 65:195-200. [PMID: 15975969 PMCID: PMC1798026 DOI: 10.1136/ard.2005.038232] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Sjögren's syndrome (SS), an autoimmune exocrinopathy mainly affecting lachrymal and salivary glands, results in ocular and oral dryness (keratoconjunctivitis sicca and xerostomia). The aetiology and pathogenesis are largely unknown; currently, only palliative treatment is available. OBJECTIVE To determine whether gene transfer of vasoactive intestinal peptide (VIP), based on its immunomodulatory properties, might be useful in the management of SS. METHODS A recombinant serotype 2 adeno-associated virus encoding the human VIP transgene (rAAV2hVIP) was constructed and its efficacy tested in the female non-obese diabetic (NOD) mouse model for SS after retrograde instillation in submandibular glands (SMGs). 10(10) particles/gland of rAAV2hVIP or rAAV2LacZ (encoding beta-galactosidase; control vector) were administered at 8 weeks of age (before sialadenitis onset). Salivary flow rates were determined before vector delivery and at time of death (16 weeks). After death, saliva, serum, and SMGs were harvested. Salivary output, inflammatory infiltrates (focus scores), VIP protein expression, cytokine profile, and serum anti-VIP antibodies were analysed. RESULTS rAAV2hVIP significantly improved the salivary flow, increased SMG and serum expression of VIP, and reduced SMG cytokines interleukin (IL) 2, IL10, IL12 (p70), and tumour necrosis factor alpha, and serum RANTES, compared with the control vector. No difference in focus scores or apoptotic rates was found; neutralising antibodies were not detected. CONCLUSIONS Local delivery of rAAV2hVIP can have disease modifying and immunosuppressive effects in SMGs of the NOD mouse model of SS. The new strategy of employing VIP prophylactically may be useful for both understanding and managing the salivary component of SS.
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Affiliation(s)
- B M Lodde
- GTTB/NIDCR, National Institutes of Health, 10 Center Drive, Room 1N114, MSC 1190, Bethesda, MD 20892-1190, USA.
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Pedersen AML, Bardow A, Nauntofte B. Salivary changes and dental caries as potential oral markers of autoimmune salivary gland dysfunction in primary Sjogren's syndrome. BMC Clin Pathol 2005; 5:4. [PMID: 15740617 PMCID: PMC554998 DOI: 10.1186/1472-6890-5-4] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2004] [Accepted: 03/01/2005] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND: the classification criteria for primary Sjogren's syndrome (pSS) include a number of oral components. In this study we evaluated if salivary flow and composition as well as dental caries are oral markers of disease severity in pSS. METHODS: in 20 patients fulfilling the American-European Consensus criteria for pSS and 20 age-matched healthy controls whole and parotid saliva flow rates and composition, measures of oral dryness, scores of decayed, missing and filled tooth surfaces (DMFS), periodontal indices, oral hygiene, and dietary habits were examined. RESULTS: in pSS, salivary flow rates, pH, and buffer capacities were lower, and DMFS, salivary sodium and chloride concentrations higher than in the healthy controls. DMFS also correlated inversely to salivary flow rates and positively to oral dryness. Apart from slightly increased gingival index, and more frequent dental visits in pSS, the periodontal condition, oral hygiene or sugar intake did not differ between these two groups. In pSS, findings were correlated to labial salivary gland focus score (FS) and presence of serum-autoantibodies to SSA/SSB (AB). The patients having both presence of AB and the highest FS (>2) also had the highest salivary sodium and chloride concentrations, the lowest salivary phosphate concentrations, lowest salivary flow rates, and highest DMFS compared to those with normal salivary concentrations of sodium and chloride at a given flow rate. CONCLUSION: the salivary changes observed in some pSS patients reflect impaired ductal salt reabsorption, but unaffected acinar transport mechanisms, despite low salivary secretion. Our results suggest that changes in salivary flow and composition as well as dental caries may serve as potential markers of the extent of autoimmune-mediated salivary gland dysfunction in pSS. The study also indicates that the ductal epithelium is functionally affected in some pSS patients, which calls for future pathophysiological studies on the mechanisms underlying this impaired salt reabsorption.
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Affiliation(s)
- Anne Marie Lynge Pedersen
- Department of Oral Medicine, Clinical Oral Physiology, Oral Pathology and Anatomy, and Copenhagen Gerodontological Research Centre, Faculty of Health Sciences, University of Copenhagen, Norre Allé 20, 2200 Copenhagen N, Denmark
| | - Allan Bardow
- Department of Oral Medicine, Clinical Oral Physiology, Oral Pathology and Anatomy, and Copenhagen Gerodontological Research Centre, Faculty of Health Sciences, University of Copenhagen, Norre Allé 20, 2200 Copenhagen N, Denmark
| | - Birgitte Nauntofte
- Department of Oral Medicine, Clinical Oral Physiology, Oral Pathology and Anatomy, and Copenhagen Gerodontological Research Centre, Faculty of Health Sciences, University of Copenhagen, Norre Allé 20, 2200 Copenhagen N, Denmark
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Dawson L, Tobin A, Smith P, Gordon T. Antimuscarinic antibodies in Sjögren's syndrome: Where are we, and where are we going? ACTA ACUST UNITED AC 2005; 52:2984-95. [PMID: 16200578 DOI: 10.1002/art.21347] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Luke Dawson
- University of Liverpool, Liverpool Merseyside, UK.
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Burnstock G, Knight GE. Cellular Distribution and Functions of P2 Receptor Subtypes in Different Systems. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 240:31-304. [PMID: 15548415 DOI: 10.1016/s0074-7696(04)40002-3] [Citation(s) in RCA: 573] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review is aimed at providing readers with a comprehensive reference article about the distribution and function of P2 receptors in all the organs, tissues, and cells in the body. Each section provides an account of the early history of purinergic signaling in the organ?cell up to 1994, then summarizes subsequent evidence for the presence of P2X and P2Y receptor subtype mRNA and proteins as well as functional data, all fully referenced. A section is included describing the plasticity of expression of P2 receptors during development and aging as well as in various pathophysiological conditions. Finally, there is some discussion of possible future developments in the purinergic signaling field.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Institute, Royal Free and University College Medical School, London NW3 2PF, United Kingdom
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Kok MR, Baum BJ, Tak PP, Pillemer SR. Use of localised gene transfer to develop new treatment strategies for the salivary component of Sjögren's syndrome. Ann Rheum Dis 2003; 62:1038-46. [PMID: 14583564 PMCID: PMC1754372 DOI: 10.1136/ard.62.11.1038] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Effective treatment for Sjögren's syndrome (SS) might be developed locally by introducing genes encoding cytokines, which are potentially anti-inflammatory, or by introducing a cDNA encoding a soluble form of a key cytokine receptor, which can act as an antagonist and decrease the availability of certain cytokines, such as soluble tumour necrosis factor alpha receptors. Currently, the preferred choice of viral vector for immunomodulatory gene transfer is recombinant adeno-associated virus. The use of gene transfer to help determine the pathophysiology and to alter the course of the SS-like disease in the NOD mouse model can ultimately lead to the development of new treatments for managing the salivary component in patients with SS.
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Affiliation(s)
- M R Kok
- Gene Therapy and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA.
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Looms D, Tritsaris K, Pedersen AM, Nauntofte B, Dissing S. Nitric oxide signalling in salivary glands. J Oral Pathol Med 2002; 31:569-84. [PMID: 12406302 DOI: 10.1034/j.1600-0714.2002.00047.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Nitric oxide (NO) plays multiple roles in both intracellular and extracellular signalling mechanisms with implications for health and disease. This review focuses on the role of NO signalling in salivary secretion. Attention will be paid primarily to endogenous NO production in acinar cells resulting from specific receptor stimulation and to NO-regulated Ca2+ homeostasis. Due to the fact that NO readily crosses membranes by simple diffusion, endogenous NO may play a physiological role in processes as diverse as modifying the secretory output, controlling blood supply to the gland, modulating transmitter output from nerve endings, participating in the host defence barrier, and affecting growth and differentiation of surrounding tissue. Furthermore, the role of NO in the pathogenesis of human oral diseases will be considered.
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Affiliation(s)
- Dagnia Looms
- Department of Medical Physiology, Faculty of Health Sciences, Panum Institute, University of Copenhagen, Denmark
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Beroukas D, Goodfellow R, Hiscock J, Jonsson R, Gordon TP, Waterman SA. Up-regulation of M3-muscarinic receptors in labial salivary gland acini in primary Sjögren's syndrome. J Transl Med 2002; 82:203-10. [PMID: 11850533 DOI: 10.1038/labinvest.3780412] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
M3-muscarinic receptors (M3R) mediate parasympathetic cholinergic neurotransmission to salivary and lacrimal glands, and autoantibodies to these receptors have been implicated in sicca symptoms and autonomic dysfunction in Sjögren's syndrome. We have investigated the expression of M3R in paraffin-embedded labial salivary glands (LSG) from seven patients with primary Sjögren's syndrome (pSS) and five healthy controls using high-resolution confocal microscopy and an affinity-purified goat polyclonal antibody raised against the COOH-terminal sequence of the human M3R. Immunolocalization of M3R was similar in control and pSS glands, with punctate staining of M3R in the basal membrane of acinar cells and in the luminal and abluminal membrane of myoepithelial cells. Bright, granular M3R staining was also detected in the cytoplasm and membranes of all intercalated and striated ducts, and infiltrating lymphocytes in pSS. All immunoreactivity was specifically blocked by the immunizing peptide. An increase in M3R expression specifically in acini in pSS was demonstrated by a 30% increase in receptor number per cluster and a 68% increase in the number of clusters in the membrane. This up-regulation is consistent with inhibition of parasympathetic neurotransmission, possibly by antagonistic autoantibodies to M3R. The up-regulation, rather than down-regulation, of M3R in acini of pSS LSG can explain the effectiveness of muscarinic agonists in treating sicca symptoms in pSS.
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Affiliation(s)
- Dimitra Beroukas
- Department of Immunology, Allergy and Arthritis, Flinders Medical Centre, Bedford Park, Australia
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Liu X, Mörk AC, Sun X, Castro R, Martinez JR, Zhang GH. Regulation of Ca(2+) signals in a parotid cell line Par-C5. Arch Oral Biol 2001; 46:1141-9. [PMID: 11684033 DOI: 10.1016/s0003-9969(01)00074-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The Ca(2+) signaling system in an established immortalized rat parotid acinar cell line, Par-C5, was examined using the Ca(2+)-sensitive fluorescent indicator fura-2 and by measuring inositol 1,4,5-trisphosphate (IP(3)) formation. Agonist-induced increase in intracellular Ca(2+) ([Ca(2+)](i)) by mobilization of intracellular stores and influx across the cell membrane was stimulated by acetylcholine (ACh) and ATP, whereas noradrenaline-(NA)-induced a small [Ca(2+)](i) increase mediated primarily by release from intracellular Ca(2+) stores. [Ca(2+)](i) increase by ACh and ATP was mediated through the phosphoinositide signal pathway since both agonists significantly increased 1,4,5-IP(3) formation and Ca(2+) mobilization was abolished by the phospholipase C inhibitor U73122. In Ca(2+)-free medium, ACh or ATP discharged the IP(3)-sensitive Ca(2+) store and essentially abolished subsequent [Ca(2+)](i) response to thapsigargin (TG). Exposure to ionomycin and monensin after TG induced a further mobilization of Ca(2+), suggesting IP(3)-insensitive stores are present. Furthermore, depletion of IP(3)-sensitive Ca(2+) stores by TG, ACh and ATP enhanced plasmalemmal Ca(2+)-entry pathways. Exposure to tumor necrosis factor-alpha (TNF-alpha), a cytokine associated with lymphocyte invasion of salivary epithelial cells in autoimmune disorders, significantly reduced ACh-stimulated Ca(2+) mobilization. TNF-alpha inhibitory effect on Ca(2+) mobilization was not directly due to an interaction on muscarinic receptors since ACh-induced 1,4,5-IP(3) formation was not altered. These results in the Par-C5 cell line indicate 1) [Ca(2+)](i) is regulated by muscarinic and P2Y-nucleotide receptors and partly by alpha(1)-adrenergic receptors; 2) IP(3)-sensitive and -insensitive Ca(2+) stores exist; 3) Ca(2+) influx activated by ACh, ATP or TG is mediated by the store-operated Ca(2+) entry pathway; and 4) muscarinic agonist-stimulated Ca(2+) mobilization is altered by the cytokine TNF-alpha.
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Affiliation(s)
- X Liu
- Secretory Cell Physiology Laboratory, Department of Pediatrics, University of Texas Health Center, Mail Code 7827, 7703 Floyd Curl Dr., San Antonio, TX 78229-3900, USA
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Dawson LJ, Field EA, Harmer AR, Smith PM. Acetylcholine-evoked calcium mobilization and ion channel activation in human labial gland acinar cells from patients with primary Sjögren's syndrome. Clin Exp Immunol 2001; 124:480-5. [PMID: 11472412 PMCID: PMC1906076 DOI: 10.1046/j.1365-2249.2001.01526.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent evidence has indicated that the salivary gland dysfunction associated with Sjögren's syndrome (SjS) is not necessarily due to immune-mediated destruction of acinar tissue. SjS sufferers may possess substantial reserves of acinar tissue but nevertheless be incapable of maintaining salivary flow rates in the normal range. We have investigated the ability of isolated labial gland acinar cells from SjS patients to fluid secrete by measuring agonist-evoked changes in intracellular Ca(2+) ([Ca(2+)](i)) using fura-2 microfluorimetry and activation of K(+) and Cl(-) channels using the patch-clamp whole cell technique. We can confirm that stimulation with a super-maximal dose of acetylcholine (ACh) increased [Ca(2+)]i equally in both control acinar cells and those derived from SjS patients. However, at submaximal concentrations, the dose-response curve for ACh was shifted to the right by approximately one order of magnitude in acinar cells from SjS patients compared to control acinar cells. Patch-clamp measurements consistent with the presence of Ca(2+)-activated K(+) and Cl(-) conductances were obtained from both control acinar cells and those obtained from SjS patients. Dose-dependent activation of the ion channels by acetylcholine was also right-shifted in acinar cells from SjS patients compared to control cells. Our data show that labial gland acinar cells from SjS patients were capable of responding to agonist stimulation by mobilizing [Ca(2+)](i) and activating K(+) and Cl(-) channels consistent with the requirements of fluid secretion. However, the persistent loss of sensitivity to ACh observed in from SjS patients may account for the lack of saliva production observed in these patients in vivo.
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Affiliation(s)
- L J Dawson
- Sjögren's Syndrome Research Group, Department of Clinical Dental Sciences, The University of Liverpool, Liverpool, UK
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Looms DK, Dissing S, Tritsaris K, Pedersen AM, Nauntofte B. Adrenoceptor-activated nitric oxide synthesis in salivary acinar cells. Adv Dent Res 2000; 14:62-8. [PMID: 11842926 DOI: 10.1177/08959374000140011001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We investigated the cellular regulation of nitric oxide synthase (NOS) activity in isolated acinar cells from rat parotid and human labial salivary glands, using the newly developed fluorescent nitric oxide (NO) indicator, DAF-2. We found that sympathetic stimulation with norepinephrine (NE) caused a strong increase in NO synthesis that was not seen after parasympathetic stimulation with acetylcholine. In rat parotid acinar cells, we furthermore investigated to which extent the NOS activity was dependent on the intracellular free Ca2+ concentration ([Ca2+]i) by simultaneously measuring NO synthesis and [Ca2+]i. It was found that a simple correlation between the rise in [Ca2+]i and the rate of NO production following NE stimulation does not exist, and studies in which [Ca2+]i was elevated by means of the Ca2+ ionophore, ionomycin, further established that even a very large rise in [Ca2+]i did not cause significant NO synthesis. We furthermore found that activating adrenoceptors with NE causes synthesis of cGMP by activating a guanylyl cyclase, and that an enhanced [cGMP] evoked by use of caged cGMP causes Ca2+ release from internal stores. Thus, upon sympathetic stimulation, salivary gland acini synthesize NO that, in addition to playing a role in controlling intracellular [Ca2+]i, also might play a role in retrograde signaling processes to the surrounding tissue.
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Affiliation(s)
- D K Looms
- The Panum Institute, Faculty of Health Sciences, University of Copenhagen, Denmark
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