1
|
Hou J, Feng Y, Yang Z, Ding Y, Cheng D, Shi Z, Li R, Xue L. Primary Sjögren's syndrome: new perspectives on salivary gland epithelial cells. Eur J Med Res 2024; 29:371. [PMID: 39014509 PMCID: PMC11253495 DOI: 10.1186/s40001-024-01967-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 07/09/2024] [Indexed: 07/18/2024] Open
Abstract
Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease primarily affecting exocrine glands such as the salivary glands, leading to impaired secretion and sicca symptoms. As the mainstay of salivation, salivary gland epithelial cells (SGECs) have an important role in the pathology of pSS. Emerging evidence suggests that the interplay between immunological factors and SGECs may not be the initial trigger or the sole mechanism responsible for xerostomia in pSS, challenging conventional perceptions. To deepen our understanding, current research regarding SGECs in pSS was reviewed. Among the extensive aberrations in cellular architecture and function, this review highlighted certain alterations of SGECs that were identified to occur independently of or in absence of lymphocytic infiltration. In particular, some of these alterations may serve as upstream factors of immuno-inflammatory responses. These findings underscore the significance of introspecting the pathogenesis of pSS and developing interventions targeting SGECs in the early stages of the disease.
Collapse
Affiliation(s)
- Jiaqi Hou
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Yiyi Feng
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Zhixia Yang
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Yimei Ding
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Dandan Cheng
- Shanghai Skin Diseases Hospital, 200 Wuyi Road, Changning District, Shanghai, 200050, China
| | - Zhonghao Shi
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Rouxin Li
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China
| | - Luan Xue
- Rheumatology Department, Yueyang Hospital of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, 110 Ganhe Road, Hongkou District, Shanghai, 200437, China.
| |
Collapse
|
2
|
Pallagi P, Tóth E, Görög M, Venglovecz V, Madácsy T, Varga Á, Molnár T, Papp N, Szabó V, Kúthy-Sutus E, Molnár R, Ördög A, Borka K, Schnúr A, Kéri A, Kajner G, Csekő K, Ritter E, Csupor D, Helyes Z, Galbács G, Szentesi A, Czakó L, Rakonczay Z, Takács T, Maléth J, Hegyi P. Heavy metals in cigarette smoke strongly inhibit pancreatic ductal function and promote development of chronic pancreatitis. Clin Transl Med 2024; 14:e1733. [PMID: 38877637 PMCID: PMC11178517 DOI: 10.1002/ctm2.1733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 04/30/2024] [Accepted: 05/21/2024] [Indexed: 06/16/2024] Open
Abstract
BACKGROUND AND AIMS Smoking is recognised as an independent risk factor in the development of chronic pancreatitis (CP). Cystic fibrosis transmembrane conductance regulator (CFTR) function and ductal fluid and bicarbonate secretion are also known to be impaired in CP, so it is crucial to understand the relationships between smoking, pancreatic ductal function and the development of CP. METHODS We measured sweat chloride (Cl-) concentrations in patients with and without CP, both smokers and non-smokers, to assess CFTR activity. Serum heavy metal levels and tissue cadmium concentrations were determined by mass spectrometry in smoking and non-smoking patients. Guinea pigs were exposed to cigarette smoke, and cigarette smoke extract (CSE) was prepared to characterise its effects on pancreatic HCO3 - and fluid secretion and CFTR function. We administered cerulein to both the smoking and non-smoking groups of mice to induce pancreatitis. RESULTS Sweat samples from smokers, both with and without CP, exhibited elevated Cl- concentrations compared to those from non-smokers, indicating a decrease in CFTR activity due to smoking. Pancreatic tissues from smokers, regardless of CP status, displayed lower CFTR expression than those from non-smokers. Serum levels of cadmium and mercury, as well as pancreatic tissue cadmium, were increased in smokers. Smoking, CSE, cadmium, mercury and nicotine all hindered fluid and HCO3 - secretion and CFTR activity in pancreatic ductal cells. These effects were mediated by sustained increases in intracellular calcium ([Ca2+]i), depletion of intracellular ATP (ATPi) and mitochondrial membrane depolarisation. CONCLUSION Smoking impairs pancreatic ductal function and contributes to the development of CP. Heavy metals, notably cadmium, play a significant role in the harmful effects of smoking. KEY POINTS Smoking and cigarette smoke extract diminish pancreatic ductal fluid and HCO3 - secretion as well as the expression and function of CFTR Cd and Hg concentrations are significantly higher in the serum samples of smokers Cd accumulates in the pancreatic tissue of smokers.
Collapse
Affiliation(s)
- Petra Pallagi
- Department of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Emese Tóth
- Department of Medicine, University of Szeged, Szeged, Hungary
- Department of Theoretical and Integrative Health Sciences, University of Debrecen, Szeged, Hungary
- Translational Pancreatology Research Group, Interdisciplinary Centre of Excellence for Research Development and Innovation, University of Szeged, Szeged, Hungary
| | - Marietta Görög
- Department of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Viktória Venglovecz
- Translational Pancreatology Research Group, Interdisciplinary Centre of Excellence for Research Development and Innovation, University of Szeged, Szeged, Hungary
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| | - Tamara Madácsy
- Department of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Árpád Varga
- Department of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Tünde Molnár
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Noémi Papp
- Department of Medicine, University of Szeged, Szeged, Hungary
| | - Viktória Szabó
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Enikő Kúthy-Sutus
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Réka Molnár
- Department of Medicine, University of Szeged, Szeged, Hungary
| | - Attila Ördög
- Department of Plant Biology, University of Szeged, Szeged, Hungary
| | - Katalin Borka
- Department of Pathology, Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Andrea Schnúr
- Department of Medicine, University of Szeged, Szeged, Hungary
| | - Albert Kéri
- Department of Molecular and Analytical Chemistry, University of Szeged, Szeged, Hungary
| | - Gyula Kajner
- Department of Molecular and Analytical Chemistry, University of Szeged, Szeged, Hungary
| | - Kata Csekő
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
- National Laboratory of Drug Research and Development (Pharmalab), Budapest, Hungary
| | - Emese Ritter
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
- National Laboratory of Drug Research and Development (Pharmalab), Budapest, Hungary
| | - Dezső Csupor
- Institute of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
- Institute of Clinical Pharmacy, University of Szeged, Szeged, Hungary
- Institute for Translational Medicine, University of Pécs, Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
- National Laboratory of Drug Research and Development (Pharmalab), Budapest, Hungary
- Eötvös Loránd Research Network Chronic Pain Research Group, University of Pécs, Pécs, Hungary
| | - Gábor Galbács
- Department of Molecular and Analytical Chemistry, University of Szeged, Szeged, Hungary
| | - Andrea Szentesi
- Institute for Translational Medicine, University of Pécs, Pécs, Hungary
| | - László Czakó
- Department of Medicine, University of Szeged, Szeged, Hungary
| | - Zoltán Rakonczay
- Department of Pathophysiology, University of Szeged, Szeged, Hungary
| | - Tamás Takács
- Department of Medicine, University of Szeged, Szeged, Hungary
| | - József Maléth
- Department of Medicine, University of Szeged, Szeged, Hungary
- MTA-SZTE Momentum Epithelial Cell Signaling and Secretion Research Group, University of Szeged, Szeged, Hungary
- HCEMM-SZTE Molecular Gastroenterology Research Group, University of Szeged, Szeged, Hungary
| | - Péter Hegyi
- Translational Pancreatology Research Group, Interdisciplinary Centre of Excellence for Research Development and Innovation, University of Szeged, Szeged, Hungary
- Institute for Translational Medicine, University of Pécs, Pécs, Hungary
- Center of Translational Medicine and Institute of Pancreatic Disorders, Semmelweis University, Budapest, Hungary
| |
Collapse
|
3
|
Morales EA, Wang S. Salivary gland developmental mechanics. Curr Top Dev Biol 2024; 160:1-30. [PMID: 38937029 DOI: 10.1016/bs.ctdb.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
The salivary gland undergoes branching morphogenesis to elaborate into a tree-like structure with numerous saliva-secreting acinar units, all joined by a hierarchical ductal system. The expansive epithelial surface generated by branching morphogenesis serves as the structural basis for the efficient production and delivery of saliva. Here, we elucidate the process of salivary gland morphogenesis, emphasizing the role of mechanics. Structurally, the developing salivary gland is characterized by a stratified epithelium tightly encased by the basement membrane, which is in turn surrounded by a mesenchyme consisting of a dense network of interstitial matrix and mesenchymal cells. Diverse cell types and extracellular matrices bestow this developing organ with organized, yet spatially varied mechanical properties. For instance, the surface epithelial sheet of the bud is highly fluidic due to its high cell motility and weak cell-cell adhesion, rendering it highly pliable. In contrast, the inner core of the bud is more rigid, characterized by reduced cell motility and strong cell-cell adhesion, which likely provide structural support for the tissue. The interactions between the surface epithelial sheet and the inner core give rise to budding morphogenesis. Furthermore, the basement membrane and the mesenchyme offer mechanical constraints that could play a pivotal role in determining the higher-order architecture of a fully mature salivary gland.
Collapse
Affiliation(s)
- E Angelo Morales
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, United States
| | - Shaohe Wang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, United States.
| |
Collapse
|
4
|
Maliszewska-Olejniczak K, Pytlak K, Dabrowska A, Zochowska M, Hoser J, Lukasiak A, Zajac M, Kulawiak B, Bednarczyk P. Deficiency of the BK Ca potassium channel displayed significant implications for the physiology of the human bronchial epithelium. Mitochondrion 2024; 76:101880. [PMID: 38604459 DOI: 10.1016/j.mito.2024.101880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/14/2024] [Accepted: 04/07/2024] [Indexed: 04/13/2024]
Abstract
Plasma membrane large-conductance calcium-activated potassium (BKCa) channels are important players in various physiological processes, including those mediated by epithelia. Like other cell types, human bronchial epithelial (HBE) cells also express BKCa in the inner mitochondrial membrane (mitoBKCa). The genetic relationships between these mitochondrial and plasma membrane channels and the precise role of mitoBKCa in epithelium physiology are still unclear. Here, we tested the hypothesis that the mitoBKCa channel is encoded by the same gene as the plasma membrane BKCa channel in HBE cells. We also examined the impact of channel loss on the basic function of HBE cells, which is to create a tight barrier. For this purpose, we used CRISPR/Cas9 technology in 16HBE14o- cells to disrupt the KCNMA1 gene, which encodes the α-subunit responsible for forming the pore of the plasma membrane BKCa channel. Electrophysiological experiments demonstrated that the disruption of the KCNMA1 gene resulted in the loss of BKCa-type channels in the plasma membrane and mitochondria. We have also shown that HBE ΔαBKCa cells exhibited a significant decrease in transepithelial electrical resistance which indicates a loss of tightness of the barrier created by these cells. We have also observed a decrease in mitochondrial respiration, which indicates a significant impairment of these organelles. In conclusion, our findings indicate that a single gene encodes both populations of the channel in HBE cells. Furthermore, this channel is critical for maintaining the proper function of epithelial cells as a cellular barrier.
Collapse
Affiliation(s)
- Kamila Maliszewska-Olejniczak
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland
| | - Karolina Pytlak
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Adrianna Dabrowska
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland
| | - Monika Zochowska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Jakub Hoser
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland
| | - Agnieszka Lukasiak
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland
| | - Miroslaw Zajac
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland
| | - Bogusz Kulawiak
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
| | - Piotr Bednarczyk
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
| |
Collapse
|
5
|
Kunzelmann K, Centeio R, Ousingsawat J, Talbi K, Seidler U, Schreiber R. SLC26A9 in airways and intestine: secretion or absorption? Channels (Austin) 2023; 17:2186434. [PMID: 36866602 PMCID: PMC9988340 DOI: 10.1080/19336950.2023.2186434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
SLC26A9 is one out of 11 proteins that belong to the SLC26A family of anion transporters. Apart from expression in the gastrointestinal tract, SLC26A9 is also found in the respiratory system, in male tissues and in the skin. SLC26A9 has gained attention because of its modifier role in the gastrointestinal manifestation of cystic fibrosis (CF). SLC26A9 appears to have an impact on the extent of intestinal obstruction caused by meconium ileus. SLC26A9 supports duodenal bicarbonate secretion, but was assumed to provide a basal Cl- secretory pathway in airways. However, recent results show that basal airway Cl- secretion is due to cystic fibrosis conductance regulator (CFTR), while SLC26A9 may rather secrete HCO3-, thereby maintaining proper airway surface liquid (ASL) pH. Moreover, SLC26A9 does not secrete but probably supports reabsorption of fluid particularly in the alveolar space, which explains early death by neonatal distress in Slc26a9-knockout animals. While the novel SLC26A9 inhibitor S9-A13 helped to unmask the role of SLC26A9 in the airways, it also provided evidence for an additional role in acid secretion by gastric parietal cells. Here we discuss recent data on the function of SLC26A9 in airways and gut, and how S9-A13 may be useful in unraveling the physiological role of SLC26A9.
Collapse
Affiliation(s)
- Karl Kunzelmann
- Institut für Physiologie, Universität, Universitätsstraße 31, Regensburg, Germany
- CONTACT Karl Kunzelmann
| | - Raquel Centeio
- Institut für Physiologie, Universität, Universitätsstraße 31, Regensburg, Germany
| | - Jiraporn Ousingsawat
- Institut für Physiologie, Universität, Universitätsstraße 31, Regensburg, Germany
| | - Khaoula Talbi
- Institut für Physiologie, Universität, Universitätsstraße 31, Regensburg, Germany
| | - Ursula Seidler
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany
| | - Rainer Schreiber
- Institut für Physiologie, Universität, Universitätsstraße 31, Regensburg, Germany
| |
Collapse
|
6
|
Rattner A, Heng JS, Winer BL, Goff LA, Nathans J. Normal and Sjogren's syndrome models of the murine lacrimal gland studied at single-cell resolution. Proc Natl Acad Sci U S A 2023; 120:e2311983120. [PMID: 37812717 PMCID: PMC10589653 DOI: 10.1073/pnas.2311983120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/28/2023] [Indexed: 10/11/2023] Open
Abstract
The lacrimal gland is of central interest in ophthalmology both as the source of the aqueous component of tear fluid and as the site of autoimmune pathology in the context of Sjogren's syndrome (SjS). To provide a foundational description of mouse lacrimal gland cell types and their patterns of gene expression, we have analyzed single-cell transcriptomes from wild-type (Balb/c) mice and from two genetically based SjS models, MRL/lpr and NOD (nonobese diabetic).H2b, and defined the localization of multiple cell-type-specific protein and mRNA markers. This analysis has uncovered a previously undescribed cell type, Car6+ cells, which are located at the junction of the acini and the connecting ducts. More than a dozen secreted polypeptides that are likely to be components of tear fluid are expressed by acinar cells and show pronounced sex differences in expression. Additional examples of gene expression heterogeneity within a single cell type were identified, including a gradient of Claudin4 along the length of the ductal system and cell-to-cell heterogeneity in transcription factor expression within acinar and myoepithelial cells. The patterns of expression of channels, transporters, and pumps in acinar, Car6+, and ductal cells make strong predictions regarding the mechanisms of water and electrolyte secretion. In MRL/lpr and NOD.H2b lacrimal glands, distinctive changes in parenchymal gene expression and in immune cell subsets reveal widespread interferon responses, a T cell-dominated infiltrate in the MRL/lpr model, and a mixed B cell and T cell infiltrate in the NOD.H2b model.
Collapse
Affiliation(s)
- Amir Rattner
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD21205
- HHMI, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Jacob S. Heng
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Briana L. Winer
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD21205
| | - Loyal A. Goff
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Kavli Neurodiscovery Institute, Baltimore, MD21205
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD21205
- HHMI, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Wilmer Eye Institute, Baltimore, MD21205
| |
Collapse
|
7
|
Sneyd J, Rugis J, Su S, Suresh V, Wahl AM, Yule DI. Simulation of Calcium Dynamics in Realistic Three-Dimensional Domains. Biomolecules 2022; 12:1455. [PMID: 36291663 PMCID: PMC9599163 DOI: 10.3390/biom12101455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 11/16/2022] Open
Abstract
The cytosolic concentration of free calcium ions ([Ca2+]) is an important intracellular messenger in most cell types, and the spatial distribution of [Ca2+] is often critical. In a salivary gland acinar cell, a polarised epithelial cell, whose principal function is to transport water and thus secrete saliva, [Ca2+] controls the secretion of primary saliva, but increases in [Ca2+] are localised to the apical regions of the cell. Hence, any quantitative explanation of how [Ca2+] controls saliva secretion must take into careful account the spatial distribution of the various Ca2+ sources, Ca2+ sinks, and Ca2+-sensitive ion channels. Based on optical slices, we have previously constructed anatomically accurate three-dimensional models of seven salivary gland acinar cells, and thus shown that a model in which Ca2+ responses are confined to the apical regions of the cell is sufficient to provide a quantitative and predictive explanation of primary saliva secretion. However, reconstruction of such anatomically accurate cells is extremely time consuming and inefficient. Here, we present an alternative, mostly automated method of constructing three-dimensional cells that are approximately anatomically accurate and show that the new construction preserves the quantitative accuracy of the model.
Collapse
Affiliation(s)
- James Sneyd
- Department of Mathematics, University of Auckland, Auckland 1142, New Zealand
| | - John Rugis
- Department of Mathematics, University of Auckland, Auckland 1142, New Zealand
| | - Shan Su
- Department of Mathematics, University of Auckland, Auckland 1142, New Zealand
| | - Vinod Suresh
- Department of Engineering Science, University of Auckland, Auckland 1142, New Zealand
| | - Amanda M. Wahl
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| | - David I. Yule
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY 14642, USA
| |
Collapse
|
8
|
Vargas-Poussou R. Pathophysiological aspects of the thick ascending limb and novel genetic defects: HELIX syndrome and transient antenatal Bartter syndrome. Pediatr Nephrol 2022; 37:239-252. [PMID: 33733301 DOI: 10.1007/s00467-021-05019-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 01/29/2021] [Accepted: 02/17/2021] [Indexed: 10/21/2022]
Abstract
The thick ascending limb plays a central role in human kidney physiology, participating in sodium reabsorption, urine concentrating mechanisms, calcium and magnesium homeostasis, bicarbonate and ammonium homeostasis, and uromodulin synthesis. This review aims to illustrate the importance of these roles from a pathophysiological point of view by describing the interactions of the key proteins of this segment and by discussing how recently identified and long-known hereditary diseases affect this segment. The descriptions of two recently described salt-losing tubulopathies, transient antenatal Bartter syndrome and HELIX syndrome, which are caused by mutations in MAGED2 and CLDN10 genes, respectively, highlight the role of new players in the modulation of sodium reabsorption the thick ascending limb.
Collapse
Affiliation(s)
- Rosa Vargas-Poussou
- Department of Molecular Genetics, Assistance Publique Hôpitaux de Paris, Hôpital Européen Georges-Pompidou, 20-40 rue Leblanc, 75015, Paris, France. .,Centre de Référence des Maladies Rénales Héréditaires de l'Enfant et de l'Adulte (MARHEA), Paris, France. .,Centre de Recherche des Cordeliers, INSERM, Sorbonne Université, Université de Paris, Paris, France.
| |
Collapse
|
9
|
Angyal D, Bijvelds MJC, Bruno MJ, Peppelenbosch MP, de Jonge HR. Bicarbonate Transport in Cystic Fibrosis and Pancreatitis. Cells 2021; 11:cells11010054. [PMID: 35011616 PMCID: PMC8750324 DOI: 10.3390/cells11010054] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 12/12/2022] Open
Abstract
CFTR, the cystic fibrosis (CF) gene-encoded epithelial anion channel, has a prominent role in driving chloride, bicarbonate and fluid secretion in the ductal cells of the exocrine pancreas. Whereas severe mutations in CFTR cause fibrosis of the pancreas in utero, CFTR mutants with residual function, or CFTR variants with a normal chloride but defective bicarbonate permeability (CFTRBD), are associated with an enhanced risk of pancreatitis. Recent studies indicate that CFTR function is not only compromised in genetic but also in selected patients with an acquired form of pancreatitis induced by alcohol, bile salts or smoking. In this review, we summarize recent insights into the mechanism and regulation of CFTR-mediated and modulated bicarbonate secretion in the pancreatic duct, including the role of the osmotic stress/chloride sensor WNK1 and the scaffolding protein IRBIT, and current knowledge about the role of CFTR in genetic and acquired forms of pancreatitis. Furthermore, we discuss the perspectives for CFTR modulator therapy in the treatment of exocrine pancreatic insufficiency and pancreatitis and introduce pancreatic organoids as a promising model system to study CFTR function in the human pancreas, its role in the pathology of pancreatitis and its sensitivity to CFTR modulators on a personalized basis.
Collapse
|
10
|
Sneyd J, Vera-Sigüenza E, Rugis J, Pages N, Yule DI. Calcium Dynamics and Water Transport in Salivary Acinar Cells. Bull Math Biol 2021; 83:31. [PMID: 33594615 PMCID: PMC8018713 DOI: 10.1007/s11538-020-00841-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/25/2020] [Indexed: 01/07/2023]
Abstract
Saliva is secreted from the acinar cells of the salivary glands, using mechanisms that are similar to other types of water-transporting epithelial cells. Using a combination of theoretical and experimental techniques, over the past 20 years we have continually developed and modified a quantitative model of saliva secretion, and how it is controlled by the dynamics of intracellular calcium. However, over approximately the past 5 years there have been significant developments both in our understanding of the underlying mechanisms and in the way these mechanisms should best be modelled. Here, we review the traditional understanding of how saliva is secreted, and describe how our work has suggested important modifications to this traditional view. We end with a brief description of the most recent data from living animals and discuss how this is now contributing to yet another iteration of model construction and experimental investigation.
Collapse
Affiliation(s)
- James Sneyd
- Department of Mathematics, The University of Auckland, Level 2, Building 303, 38 Princes Street, Auckland, New Zealand.
| | | | | | | | - David I Yule
- School of Medicine and Dentistry, University of Rochester Medical Center, 601 Elmwood Ave, Box 711, Rochester, NY, USA
| |
Collapse
|
11
|
Berczeli O, Szarka D, Elekes G, Vizvári E, Szalay L, Almássy J, Tálosi L, Ding C, Tóth-Molnár E. The regulatory role of vasoactive intestinal peptide in lacrimal gland ductal fluid secretion: A new piece of the puzzle in tear production. Mol Vis 2020; 26:780-788. [PMID: 33311973 PMCID: PMC7722779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 12/04/2020] [Indexed: 11/13/2022] Open
Abstract
Purpose Vasoactive intestinal peptide (VIP) is an important regulator of lacrimal gland (LG) function although the effect of VIP on ductal fluid secretion is unknown. Therefore, the aim of the present study was to investigate the role of VIP in the regulation of fluid secretion of isolated LG ducts and to analyze the underlying intracellular mechanisms. Methods LGs from wild-type (WT) and cystic fibrosis transmembrane conductance regulator (CFTR) knockout (KO) mice were used. Immunofluorescence was applied to confirm the presence of VIP receptors termed VPAC1 and VPAC2 in LG duct cells. Ductal fluid secretion evoked by VIP (100 nM) was measured in isolated ducts using videomicroscopy. Intracellular Ca2+ signaling underlying VIP stimulation was investigated with microfluorometry. Results VIP stimulation resulted in a robust and continuous fluid secretory response in isolated duct segments originated from WT mice. In contrast, CFTR KO ducts exhibited only a weak pulse-like secretion. A small but statistically significant increase was detected in the intracellular Ca2+ level [Ca2+]i during VIP stimulation in the WT and in CFTR KO ducts. VIP-evoked changes in [Ca2+]i did not differ considerably between the WT and CFTR KO ducts. Conclusions These results suggest the importance of VIP in the regulation of ductal fluid secretion and the determining role of the adenylyl cyclase-cAMP-CFTR route in this process.
Collapse
Affiliation(s)
- Orsolya Berczeli
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Dóra Szarka
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Gréta Elekes
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Eszter Vizvári
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - László Szalay
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - László Tálosi
- Department of Pharmacognosy, University of Szeged, Szeged, Hungary
| | - Chuanqing Ding
- Department of Pharmacology & Pharmaceutical Sciences, Ophthalmology, University of Southern California, Los Angeles, CA
| | - Edit Tóth-Molnár
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| |
Collapse
|
12
|
Ji M, Kim HJ, Ahn CB, Son KH, Hong JH. Cellular channelopathy mediated by hypergravity: IL-6-mediated Nkcc1 activation and enhanced Trpm2 expression in rat atrium. Cell Tissue Res 2020; 383:1017-1024. [PMID: 33159577 DOI: 10.1007/s00441-020-03299-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 09/14/2020] [Indexed: 12/23/2022]
Abstract
Although cardiac tissue is considered a target of gravitational force (g-force), the mechanism of hypergravity on the ion modulation or identification of ion transporters is still unknown. Thus, we determine the effect of hypergravity on a physical force-sensitive cytokine, IL-6 and its related channel activity to investigate rat cardiac function changes in response to accelerated g-force. Serum IL-6 levels and intracellular calcium levels of the right atrium were moderately increased under hypergravity stimulation (4g). IL-6 was involved in the modulation of sodium-potassium-chloride cotransporter (Nkcc) activity. Surprisingly, the right atrium under 4g revealed significantly enhanced Nkcc1 activity. The use of IL-6 on the NKCC1-overexpressed or native NKCC-expressing cells also showed enhanced NKCC1 activity. Hypergravity conditions were also involved in the oxidative stress activated Trpm2 channel and revealed an enhanced expression of the Trpm2 channel under 4g in the rat right atrium. In conclusion, hypergravity revealed that moderate increases in serum IL-6 and enhanced Nkcc1 activity was modulated by IL-6. In addition, enhanced Trpm2 channel expression could be involved in the increased intracellular calcium levels of the right atrium under hypergravitational force. We therefore address that enhanced physical force-sensitive cytokine and oxidative stress by the gravitational force mediate activation of the cotransporter involved in possibilities of edema and calcium loading in cardiac tissue.
Collapse
Affiliation(s)
- Minjeong Ji
- Department of Physiology, College of Medicine, Gachon University, Lee Gil Ya Cancer and Diabetes Institute, 155 Getbeolro, Yeonsu-gu, Incheon, 21999, South Korea
| | - Hyun Ji Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Inha University College of Medicine, 27 Inhang-ro, Jung-gu, Incheon, 22332, South Korea
| | - Chi Bum Ahn
- Center for Information Security Technologies, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, South Korea
| | - Kuk Hui Son
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon, 21565, South Korea.
| | - Jeong Hee Hong
- Department of Physiology, College of Medicine, Gachon University, Lee Gil Ya Cancer and Diabetes Institute, 155 Getbeolro, Yeonsu-gu, Incheon, 21999, South Korea. .,Department of Health Sciences and Technology, GAIHST, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 155 Getbeolro, Yeonsu-gu, Incheon, 21999, South Korea.
| |
Collapse
|
13
|
Tóth-Molnár E, Ding C. New insight into lacrimal gland function: Role of the duct epithelium in tear secretion. Ocul Surf 2020; 18:595-603. [DOI: 10.1016/j.jtos.2020.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/21/2020] [Accepted: 07/07/2020] [Indexed: 02/08/2023]
|
14
|
Chen Y, Wang L, Luo S, Hu J, Huang X, Li PW, Zhang Y, Wu C, Tian BL. Enhancement of Antitumor Efficacy of Paclitaxel-Loaded PEGylated Liposomes by N,N-Dimethyl Tertiary Amino Moiety in Pancreatic Cancer. Drug Des Devel Ther 2020; 14:2945-2957. [PMID: 32801636 PMCID: PMC7398872 DOI: 10.2147/dddt.s261017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/26/2020] [Indexed: 02/05/2023] Open
Abstract
Introduction Pancreatic cancer, or pancreatic duct adenocarcinoma (PDAC), remains one of the most lethal cancers and features insidious onset, highly aggressive behavior and early distant metastasis. The dense fibrotic stroma surrounding tumor cells is thought to be a shield to resist the permeation of chemotherapy drugs in the treatment of PDAC. Thus, we synthesized a pancreas-targeting paclitaxel-loaded PEGylated liposome and investigated its antitumor efficacy in the patient-derived orthotopic xenograft (PDOX) nude mouse models of PDAC. Methods The PTX-loaded PEGylated liposomes were prepared by film dispersion-ultrasonic method and modified by an N,N-dimethyl tertiary amino residue. Morphology characteristics of the PTX-loaded liposomes were observed by transmission electron microscope (TEM). The PDOX models of PDAC were established by orthotopic implantation and imaged by a micro positron emission tomography/computed tomography (PET/CT) imaging system. The in vivo distribution and antitumor study were then carried out to observe the pancreas-targeting accumulation and the antitumor efficacy of the proposed PTX liposomes. Results PTX loaded well into both modified (PTX-Lip2N) and unmodified (PTX-Lip) PEGylated liposomes with spherical shapes and suitable parameters for the endocytosis process. The PDOX nude mouse models were successfully created in which high 18F-FDG intaking regions were observed by micro-PET/CT. In addition to higher cellular uptakes of PTX-Lip2N by the BxPC-3 cells, the proposed nanoparticle had a notable penetrating ability towards PDAC tumor tissues, and consequently, the antitumor ability of PTX-Lip2N was significantly superior to the unmodified PTX-Lip in vivo PDOX models and even more effective than nab-PTX in restraining tumor growth. Conclusion The modified pancreas-targeting PTX-loaded PEGylated liposomes provide a promising platform for the treatment of pancreatic cancer.
Collapse
Affiliation(s)
- Yang Chen
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Li Wang
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Shi Luo
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu 610041, People's Republic of China
| | - Jun Hu
- Laboratory of Basic Scientific Research, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Xing Huang
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Pei-Wen Li
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu 610041, People's Republic of China
| | - Yi Zhang
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Chao Wu
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| | - Bo-Le Tian
- Department of Pancreatic Surgery, West China Hospital of Sichuan University, Chengdu 610041, Sichuan Province, People's Republic of China
| |
Collapse
|
15
|
Chen L, Ding Y, Hou Y, Liu Y, Nie H. Regulation of Cl- Electrolyte Permeability in Epithelia by Active Traditional Chinese Medicine Monomers for Diarrhea. Curr Drug Targets 2020; 21:902-909. [PMID: 32364074 DOI: 10.2174/1389450121666200504073635] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/25/2020] [Accepted: 02/28/2020] [Indexed: 11/22/2022]
Abstract
The epithelial layer, lining the inner surface of the mammalian alveolar, kidney, brain and colon, is a typical electrolyte transporting tissue. Large quantities of salt and fluid are actively moved from the mucosal side toward the blood vessel. Transepithelial salt re-absorption in epithelial tissues plays an important role in maintaining fluid homeostasis. In absorptive epithelium, fluid and salt flux is controlled by the machinery mainly composed of epithelial sodium channel, cystic fibrosis transmembrane conductance regulator, Na+-K+-2Cl- cotransporter, Na+/H+ exchanger, and Na+/K+-ATPase. Dysregulation of salt permeability across epithelium contributes to the pathogenesis of organ edema. In numerous ion transporters, epithelial Cl- transportation plays an important role in water secretion across epithelial tissues and regulation of body fluid content. Many traditional Chinese medicines treat diarrhea by regulating the Cl- electrolyte transport. We systematically summarized the recent progress regarding the traditional Chinese medicine on Cl- electrolyte transport in the intestinal epithelial tissues. The pharmaceutical relevance of developing advanced strategies to mitigate edematous disorders is also implicated. In conclusion, the crosstalk between Cl- electrolyte transport and active traditional Chinese medicine monomers may lead to the development of new strategies for diarrhea by manipulating the function and expression of ion channels.
Collapse
Affiliation(s)
- Lei Chen
- China Medical University, Shenyang, China
| | - Yan Ding
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yapeng Hou
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Yanhong Liu
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Hongguang Nie
- Department of Stem Cells and Regenerative Medicine, College of Basic Medical Science, China Medical University, Shenyang, China
| |
Collapse
|
16
|
Mouse pancreatic ductal organoid culture as a relevant model to study exocrine pancreatic ion secretion. J Transl Med 2020; 100:84-97. [PMID: 31409889 DOI: 10.1038/s41374-019-0300-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 06/19/2019] [Accepted: 06/19/2019] [Indexed: 12/14/2022] Open
Abstract
Pancreatic exocrine secretory processes are challenging to investigate on primary epithelial cells. Pancreatic organoid cultures may help to overcome shortcomings of the current models, however the ion secretory processes in pancreatic organoids-and therefore their physiological relevance or their utility in disease modeling-are not known. To answer these questions, we provide side-by-side comparison of gene expression, morphology, and function of epithelial cells in primary isolated pancreatic ducts and organoids. We used mouse pancreatic ductal fragments for experiments or were grown in Matrigel to obtain organoid cultures. Using PCR analysis we showed that gene expression of ion channels and transporters remarkably overlap in primary ductal cells and organoids. Morphological analysis with scanning electron microscopy revealed that pancreatic organoids form polarized monolayers with brush border on the apical membrane. Whereas the expression and localization of key proteins involved in ductal secretion (cystic fibrosis transmembrane conductance regulator, Na+/H+ exchanger 1 and electrogenic Na+/HCO3- cotransporter 1) are equivalent to the primary ductal fragments. Measurements of intracellular pH and Cl- levels revealed no significant difference in the activities of the apical Cl-/HCO3- exchange, or in the basolateral Na+ dependent HCO3- uptake. In summary we found that ion transport activities in the mouse pancreatic organoids are remarkably similar to those observed in freshly isolated primary ductal fragments. These results suggest that organoids can be suitable and robust model to study pancreatic ductal epithelial ion transport in health and diseases and facilitate drug development for secretory pancreatic disorders like cystic fibrosis, or chronic pancreatitis.
Collapse
|
17
|
Abstract
Cl- is the major extracellular (Cl-out) and intracellular (Cl-in) anion whose concentration is actively regulated by multiple transporters. These transporters generate Cl- gradients across the plasma membrane and between the cytoplasm and intracellular organelles. [Cl-]in changes rapidly in response to cell stimulation and influences many physiological functions, as well as cellular and systemic homeostasis. However, less appreciated is the signaling function of Cl-. Cl- interacts with multiple proteins to directly modify their activity. This review highlights the signaling function of Cl- and argues that Cl- is a bona fide signaling ion, a function deserving extensive exploration.
Collapse
Affiliation(s)
- Benjamin P Lüscher
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Laura Vachel
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Ehud Ohana
- Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Shmuel Muallem
- Epithelial Signaling and Transport Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
18
|
Racz R, Nagy A, Rakonczay Z, Dunavari EK, Gerber G, Varga G. Defense Mechanisms Against Acid Exposure by Dental Enamel Formation, Saliva and Pancreatic Juice Production. Curr Pharm Des 2019; 24:2012-2022. [PMID: 29769002 PMCID: PMC6225347 DOI: 10.2174/1381612824666180515125654] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 04/30/2018] [Accepted: 05/08/2018] [Indexed: 12/16/2022]
Abstract
The pancreas, the salivary glands and the dental enamel producing ameloblasts have marked developmental, structural and functional similarities. One of the most striking similarities is their bicarbonate-rich secretory product, serving acid neutralization. An important difference between them is that while pancreatic juice and saliva are delivered into a lumen where they can be collected and analyzed, ameloblasts produce locally precipitating hydroxyapatite which cannot be easily studied. Interestingly, the ion and protein secretion by the pancreas, the salivary glands, and maturation ameloblasts are all two-step processes, of course with significant differences too. As they all have to defend against acid exposure by producing extremely large quantities of bicarbonate, the failure of this function leads to deteriorating consequences. The aim of the present review is to describe and characterize the defense mechanisms of the pancreas, the salivary glands and enamel-producing ameloblasts against acid exposure and to compare their functional capabilities to do this by producing bicarbonate.
Collapse
Affiliation(s)
- Robert Racz
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Akos Nagy
- Department of Dentistry, Oral and Maxillofacial Surgery, University of Pecs, Pecs, Hungary
| | - Zoltan Rakonczay
- Department of Pathophysiology, University of Szeged, Szeged, Hungary
| | - Erika Katalin Dunavari
- Department of Dentistry, Oral and Maxillofacial Surgery, University of Pecs, Pecs, Hungary
| | - Gabor Gerber
- Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary
| | - Gabor Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| |
Collapse
|
19
|
Yang NY, Mukaibo T, Kurtz I, Melvin JE. The apical Na + -HCO 3 - cotransporter Slc4a7 (NBCn1) does not contribute to bicarbonate transport by mouse salivary gland ducts. J Cell Physiol 2019; 234:16376-16388. [PMID: 30767201 PMCID: PMC6694005 DOI: 10.1002/jcp.28306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/05/2019] [Accepted: 01/18/2019] [Indexed: 01/25/2023]
Abstract
The HCO3 - secretion mechanism in salivary glands is unclear but is thought to rely on the co-ordinated activity of multiple ion transport proteins including members of the Slc4 family of bicarbonate transporters. Slc4a7 was immunolocalized to the apical membrane of mouse submandibular duct cells. In contrast, Slc4a7 was not detected in acinar cells, and correspondingly, Slc4a7 disruption did not affect fluid secretion in response to cholinergic or β-adrenergic stimulation in the submandibular gland (SMG). Much of the Na + -dependent intracellular pH (pH i ) regulation in SMG duct cells was insensitive to 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid, S0859, and to the removal of extracellular HCO 3 - . Consistent with these latter observations, the Slc4a7 null mutation had no impact on HCO 3 - secretion nor on pH i regulation in duct cells. Taken together, our results revealed that Slc4a7 targets to the apical membrane of mouse SMG duct cells where it contributes little if any to pH i regulation or stimulated HCO 3 - secretion.
Collapse
Affiliation(s)
- Ning-Yan Yang
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA,Department of Pediatric Dentistry, Beijing Stomatological Hospital & School of Stomatology, Capital Medical University, Beijing, 100050, China
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA,Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Ira Kurtz
- Department of Medicine, Division of Nephrology, David Geffen School of Medicine, and the Brain Research Institute, University of California, Los Angeles, CA, 90095, USA
| | - James E. Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
| |
Collapse
|
20
|
Seidler U, Nikolovska K. Slc26 Family of Anion Transporters in the Gastrointestinal Tract: Expression, Function, Regulation, and Role in Disease. Compr Physiol 2019; 9:839-872. [DOI: 10.1002/cphy.c180027] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
21
|
Williams JA. Cholecystokinin (CCK) Regulation of Pancreatic Acinar Cells: Physiological Actions and Signal Transduction Mechanisms. Compr Physiol 2019; 9:535-564. [PMID: 30873601 DOI: 10.1002/cphy.c180014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pancreatic acinar cells synthesize and secrete about 20 digestive enzymes and ancillary proteins with the processes that match the supply of these enzymes to their need in digestion being regulated by a number of hormones (CCK, secretin and insulin), neurotransmitters (acetylcholine and VIP) and growth factors (EGF and IGF). Of these regulators, one of the most important and best studied is the gastrointestinal hormone, cholecystokinin (CCK). Furthermore, the acinar cell has become a model for seven transmembrane, heterotrimeric G protein coupled receptors to regulate multiple processes by distinct signal transduction cascades. In this review, we briefly describe the chemistry and physiology of CCK and then consider the major physiological effects of CCK on pancreatic acinar cells. The majority of the review is devoted to the physiologic signaling pathways activated by CCK receptors and heterotrimeric G proteins and the functions they affect. The pathways covered include the traditional second messenger pathways PLC-IP3-Ca2+ , DAG-PKC, and AC-cAMP-PKA/EPAC that primarily relate to secretion. Then there are the protein-protein interaction pathways Akt-mTOR-S6K, the three major MAPK pathways (ERK, JNK, and p38 MAPK), and Ca2+ -calcineurin-NFAT pathways that primarily regulate non-secretory processes including biosynthesis and growth, and several miscellaneous pathways that include the Rho family small G proteins, PKD, FAK, and Src that may regulate both secretory and nonsecretory processes but are not as well understood. © 2019 American Physiological Society. Compr Physiol 9:535-564, 2019.
Collapse
Affiliation(s)
- John A Williams
- University of Michigan, Departments of Molecular & Integrative Physiology and Internal Medicine (Gastroenterology), Ann Arbor, Michigan, USA
| |
Collapse
|
22
|
Madácsy T, Pallagi P, Maleth J. Cystic Fibrosis of the Pancreas: The Role of CFTR Channel in the Regulation of Intracellular Ca 2+ Signaling and Mitochondrial Function in the Exocrine Pancreas. Front Physiol 2018; 9:1585. [PMID: 30618777 PMCID: PMC6306458 DOI: 10.3389/fphys.2018.01585] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/23/2018] [Indexed: 12/26/2022] Open
Abstract
Cystic fibrosis (CF) is the most common genetic disorder that causes a significant damage in secretory epithelial cells due to the defective ion flux across the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel. Pancreas is one of the organs most frequently damaged by the disease leading to pancreatic insufficiency, abdominal pain and an increased risk of acute pancreatitis in CF patients causing a significant decrease in the quality of life. CFTR plays a central role in the pancreatic ductal secretory functions by carrying Cl- and HCO3 - ions across the apical membrane. Therefore pathophysiological studies in CF mostly focused on the effects of impaired ion secretion by pancreatic ductal epithelial cells leading to exocrine pancreatic damage. However, several studies indicated that CFTR has a central role in the regulation of intracellular signaling processes and is now more widely considered as a signaling hub in epithelial cells. In contrast, elevated intracellular Ca2+ level was observed in the lack of functional CFTR in different cell types including airway epithelial cells. In addition, impaired CFTR expression has been correlated with damaged mitochondrial function in epithelial cells. These alterations of intracellular signaling in CF are not well characterized in the exocrine pancreas yet. Therefore in this review we would like to summarize the complex role of CFTR in the exocrine pancreas with a special focus on the intracellular signaling and mitochondrial function.
Collapse
Affiliation(s)
- Tamara Madácsy
- First Department of Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithel Cell Signalling and Secretion Research Group, Szeged, Hungary
| | - Petra Pallagi
- First Department of Medicine, University of Szeged, Szeged, Hungary
| | - Jozsef Maleth
- First Department of Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithel Cell Signalling and Secretion Research Group, Szeged, Hungary.,Department of Public Health, University of Szeged, Szeged, Hungary
| |
Collapse
|
23
|
Fang L, Lee HW, Chen C, Harris AN, Romero MF, Verlander JW, Weiner ID. Expression of the B splice variant of NBCe1 (SLC4A4) in the mouse kidney. Am J Physiol Renal Physiol 2018; 315:F417-F428. [PMID: 29631353 PMCID: PMC6172571 DOI: 10.1152/ajprenal.00515.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 03/07/2018] [Accepted: 03/29/2018] [Indexed: 01/10/2023] Open
Abstract
Sodium-coupled bicarbonate transporters are critical for renal electrolyte transport. The electrogenic, sodium-coupled bicarbonate cotransporter, isoform 1 (NBCe1), encoded by the SLC4A4 geneencoded by the SLC4A4 gene has five multiple splice variants; the A splice variant, NBCe1-A, is the primary basolateral bicarbonate transporter in the proximal convoluted tubule. This study's purpose was to determine if there is expression of additional NBCe1 splice variants in the mouse kidney, their cellular distribution, and their regulation by metabolic acidosis. In wild-type mice, an antibody reactive only to NBCe1-A showed basolateral immunolabel only in cortical proximal tubule (PT) segments, whereas an antibody reactive to all NBCe1 splice variants (pan-NBCe1) showed basolateral immunolabel in PT segments in both the cortex and outer medulla. In mice with NBCe1-A deletion, the pan-NBCe1 antibody showed basolateral PT immunolabel in both the renal cortex and outer stripe of the outer medulla, and immunoblot analysis showed expression of a ~121-kDa protein. RT-PCR of mRNA from NBCe1-A knockout mice directed at splice variant-specific regions showed expression of only NBCe1-B mRNA. In wild-type kidney, RT-PCR confirmed expression of mRNA for the NBCe1-B splice variant and absence of mRNA for the C, D, and E splice variants. Finally, exogenous acid loading increased expression in the proximal straight tubule in the outer stripe of the outer medulla. These studies demonstrate that the NBCe1-B splice variant is present in the PT, and its expression increases in response to exogenous acid loading, suggesting it participates in the PT contribution to acid-base homeostasis.
Collapse
Affiliation(s)
- Lijuan Fang
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
| | - Hyun-Wook Lee
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
| | - Chao Chen
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
| | - Autumn N Harris
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
| | - Michael F Romero
- Department of Physiology and Biomedical Engineering, Mayo Clinic , Rochester, Minnesota
| | - Jill W Verlander
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
| | - I David Weiner
- Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine , Gainesville, Florida
- Nephrology and Hypertension Section, North Florida/South Georgia Veterans Health System, Gainesville, Florida
| |
Collapse
|
24
|
Berczeli O, Vizvári E, Katona M, Török D, Szalay L, Rárosi F, Németh I, Rakonczay Z, Hegyi P, Ding C, Tóth-Molnár E. Novel Insight Into the Role of CFTR in Lacrimal Gland Duct Function in Mice. Invest Ophthalmol Vis Sci 2018; 59:54-62. [PMID: 29305607 PMCID: PMC5756044 DOI: 10.1167/iovs.17-22533] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose The role of cystic fibrosis transmembrane conductance regulator (CFTR) in lacrimal gland (LG) function has only recently received some attention, mainly from our group. In the present study, we investigated the potential changes of LG pathology, tear secretion, ocular surface integrity, and fluid secretion in isolated LG ducts from CFTR knockout (KO) mice. Methods Tear production and ocular surface integrity were investigated in anesthetized wild-type (WT) and KO mice using cotton threads and fluorescein staining, respectively. Immunofluorescence was used to localize CFTR protein in the LGs. Ductal fluid secretions evoked by forskolin (10 μM); cell-permeable cAMP analogue (8-bromo cAMP, 100 μM); or carbachol (100 μM) were measured in isolated LG ducts using video-microscopy. Intracellular Ca2+ homeostasis underlying carbachol stimulation was investigated with microfluorometry. Results Significant decrease in tear secretion and impaired ocular surface integrity were observed in KO mice. Immunofluorescence demonstrated the predominant presence of CFTR protein in the apical membranes of the duct cells from WT mice. Continuous fluid secretion was evoked by forskolin and 8-bromo cAMP in LG ducts from WT mice, while no secretory response was observed in ducts from KO mice. Carbachol caused similar secretory responses in ducts from WT and KO animals without significant differences in cytosolic Ca2+ signaling. Conclusions Our results suggest the important role of CFTR in LG ductal secretion and in the maintenance of ocular surface integrity, suggesting that CFTR may be a promising target of novel therapeutic approaches in the treatment of dry eye.
Collapse
Affiliation(s)
- Orsolya Berczeli
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Eszter Vizvári
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Máté Katona
- 1st Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Dénes Török
- Department of Anatomy, University of Szeged, Szeged, Hungary
| | - László Szalay
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Ferenc Rárosi
- Department of Medical Physics and Informatics, University of Szeged, Szeged, Hungary
| | - István Németh
- Department of Dermatology and Allergology, University of Szeged, Szeged, Hungary
| | - Zoltán Rakonczay
- 1st Department of Internal Medicine, University of Szeged, Szeged, Hungary.,Department of Pathophysiology, University of Szeged, Szeged, Hungary
| | - Péter Hegyi
- Institute for Translational Medicine and First Department of Medicine, University of Pécs, Pécs, Hungary.,MTA-SZTE Translational Gastroenterology Research Group, Szeged, Hungary
| | - Chuanqing Ding
- Pharmacology & Pharmaceutical Sciences, Ophthalmology, University of Southern California, Los Angeles, California, United States
| | - Edit Tóth-Molnár
- Department of Ophthalmology, University of Szeged, Szeged, Hungary.,Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary
| |
Collapse
|
25
|
Deconstructing the principles of ductal network formation in the pancreas. PLoS Biol 2018; 16:e2002842. [PMID: 30048442 PMCID: PMC6080801 DOI: 10.1371/journal.pbio.2002842] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/07/2018] [Accepted: 07/16/2018] [Indexed: 12/18/2022] Open
Abstract
The mammalian pancreas is a branched organ that does not exhibit stereotypic branching patterns, similarly to most other glands. Inside branches, it contains a network of ducts that undergo a transition from unconnected microlumen to a mesh of interconnected ducts and finally to a treelike structure. This ductal remodeling is poorly understood, both on a microscopic and macroscopic level. In this article, we quantify the network properties at different developmental stages. We find that the pancreatic network exhibits stereotypic traits at each stage and that the network properties change with time toward the most economical and optimized delivery of exocrine products into the duodenum. Using in silico modeling, we show how steps of pancreatic network development can be deconstructed into two simple rules likely to be conserved for many other glands. The early stage of the network is explained by noisy, redundant duct connection as new microlumens form. The later transition is attributed to pruning of the network based on the flux of fluid running through the pancreatic network into the duodenum. In the pancreas of mammals, digestive enzymes are transported from their production site in acini (clusters of cells that secrete the enzymes) to the intestine via a network of ducts. During organ development in fetuses, the ducts initially form by the coordinated polarization of cells to form small holes, which will connect and fuse, to constitute a meshwork. This hyperconnected network further develops into a treelike structure by the time of birth. In this article, we use methods originally developed to analyze road, rail, web, or river networks to quantify the network properties at different developmental stages. We find that the pancreatic network properties are similar between individuals at specific time points but eventually change to achieve the most economical and optimized structure to deliver pancreatic juice into the duodenum. Using in silico modeling, we show how the stages of pancreatic network development follow two simple rules, which are likely to be conserved for the development of other glands. The early stage of the network is explained by noisy, redundant duct connection as new small ductal holes form. Later on, the secretion of fluid that runs through the pancreatic network into the duodenum leads to the widening of ducts with the greatest flow, while nonnecessary ducts are eliminated, akin to how river beds are formed.
Collapse
|
26
|
Mukaibo T, Munemasa T, George AT, Tran DT, Gao X, Herche JL, Masaki C, Shull GE, Soleimani M, Melvin JE. The apical anion exchanger Slc26a6 promotes oxalate secretion by murine submandibular gland acinar cells. J Biol Chem 2018; 293:6259-6268. [PMID: 29530983 PMCID: PMC5925796 DOI: 10.1074/jbc.ra118.002378] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/08/2018] [Indexed: 12/15/2022] Open
Abstract
The solute carrier family 26 (SLC26) gene family encodes at least 10 different anion exchangers. SLC26 member 6 (SLC26A6 or CFEX/PAT-1) and the cystic fibrosis transmembrane conductance regulator (CFTR) co-localize to the apical membrane of pancreatic duct cells, where they act in concert to drive HCO3- and fluid secretion. In contrast, in the small intestine, SLC26A6 serves as the major pathway for oxalate secretion. However, little is known about the function of Slc26a6 in murine salivary glands. Here, RNA sequencing-based transcriptional profiling and Western blots revealed that Slc26a6 is highly expressed in mouse submandibular and sublingual salivary glands. Slc26a6 localized to the apical membrane of salivary gland acinar cells with no detectable immunostaining in the ducts. CHO-K1 cells transfected with mouse Slc26a6 exchanged Cl- for oxalate and HCO3-, whereas two other anion exchangers known to be expressed in salivary gland acinar cells, Slc4a4 and Slc4a9, mediated little, if any, Cl-/oxalate exchange. Of note, both Cl-/oxalate exchange and Cl-/HCO3- exchange were significantly reduced in acinar cells isolated from the submandibular glands of Slc26a6-/- mice. Oxalate secretion in submandibular saliva also decreased significantly in Slc26a6-/- mice, but HCO3- secretion was unaffected. Taken together, our findings indicate that Slc26a6 is located at the apical membrane of salivary gland acinar cells, where it mediates Cl-/oxalate exchange and plays a critical role in the secretion of oxalate into saliva.
Collapse
Affiliation(s)
- Taro Mukaibo
- From the Secretory Mechanisms and Dysfunctions Section and
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Takashi Munemasa
- From the Secretory Mechanisms and Dysfunctions Section and
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Alvin T George
- From the Secretory Mechanisms and Dysfunctions Section and
| | - Duy T Tran
- Biological Chemistry Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Xin Gao
- From the Secretory Mechanisms and Dysfunctions Section and
- the Joint Institute for Food Safety and Applied Nutrition, University of Maryland, College Park, Maryland 20742, and
| | - Jesse L Herche
- From the Secretory Mechanisms and Dysfunctions Section and
| | - Chihiro Masaki
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Gary E Shull
- Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | | | - James E Melvin
- From the Secretory Mechanisms and Dysfunctions Section and
| |
Collapse
|
27
|
Ruhr IM, Schauer KL, Takei Y, Grosell M. Renoguanylin stimulates apical CFTR translocation and decreases HCO 3- secretion through PKA activity in the Gulf toadfish ( Opsanus beta). ACTA ACUST UNITED AC 2018; 221:jeb.173948. [PMID: 29361605 DOI: 10.1242/jeb.173948] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/15/2018] [Indexed: 01/07/2023]
Abstract
The guanylin peptides - guanylin, uroguanylin and renoguanylin (RGN) - are endogenously produced hormones in teleost fish enterocytes that are activators of guanylyl cyclase-C (GC-C) and are potent modulators of intestinal physiology, particularly in seawater teleosts. Most notably, they reverse normal net ion-absorbing mechanisms that are vital to water absorption, an important process for seawater teleost survival. The role of guanylin-peptide stimulation of the intestine remains unclear, but it is hypothesized to facilitate the removal of solids from the intestine by providing fluid to enable their removal by peristalsis. The present study used one member of this group of peptides - RGN - to provide evidence for the prominent role that protein kinase A (PKA) plays in mediating the effects of guanylin-peptide stimulation in the posterior intestine of the Gulf toadfish (Opsanus beta). Protein kinase G was found to not mediate the intracellular effects of RGN, despite previous evidence showing that GC-C activation leads to higher cyclic guanosine monophosphate formation. RGN reversed the absorptive short-circuit current and increased conductance in the Gulf toadfish intestine. These effects are correlated to increased trafficking of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel to the apical membrane, which is negated by PKA inhibition. Moreover, RGN decreased HCO3- secretion, likely by limiting apical HCO3-/Cl- exchange (possibly by reducing SLC26a6 activity), a reduction that was enhanced by PKA inhibition. RGN seems to alter PKA activity in the posterior intestine to recruit CFTR to the apical membrane and reduce HCO3- secretion.
Collapse
Affiliation(s)
- Ilan M Ruhr
- Department of Marine Biology and Ecology, The Rosenstiel School of Marine and Atmospheric Science, The University of Miami, Miami, FL 33149, USA
| | - Kevin L Schauer
- Department of Marine Biology and Ecology, The Rosenstiel School of Marine and Atmospheric Science, The University of Miami, Miami, FL 33149, USA
| | - Yoshio Takei
- Department of Marine Bioscience, The Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Martin Grosell
- Department of Marine Biology and Ecology, The Rosenstiel School of Marine and Atmospheric Science, The University of Miami, Miami, FL 33149, USA
| |
Collapse
|
28
|
Gao X, Oei MS, Ovitt CE, Sincan M, Melvin JE. Transcriptional profiling reveals gland-specific differential expression in the three major salivary glands of the adult mouse. Physiol Genomics 2018; 50:263-271. [PMID: 29373073 DOI: 10.1152/physiolgenomics.00124.2017] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
RNA-Seq was used to better understand the molecular nature of the biological differences among the three major exocrine salivary glands in mammals. Transcriptional profiling found that the adult murine parotid, submandibular, and sublingual salivary glands express greater than 14,300 protein-coding genes, and nearly 2,000 of these genes were differentially expressed. Principle component analysis of the differentially expressed genes revealed three distinct clusters according to gland type. The three salivary gland transcriptomes were dominated by a relatively few number of highly expressed genes (6.3%) that accounted for more than 90% of transcriptional output. Of the 912 transcription factors expressed in the major salivary glands, greater than 90% of them were detected in all three glands, while expression for ~2% of them was enriched in an individual gland. Expression of these unique transcription factors correlated with sublingual and parotid specific subsets of both highly expressed and differentially expressed genes. Gene ontology analyses revealed that the highly expressed genes common to all glands were associated with global functions, while many of the genes expressed in a single gland play a major role in the function of that gland. In summary, transcriptional profiling of the three murine major salivary glands identified a limited number of highly expressed genes, differentially expressed genes, and unique transcription factors that represent the transcriptional signatures underlying gland-specific biological properties.
Collapse
Affiliation(s)
- Xin Gao
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health , Bethesda, Maryland.,Joint Institute for Food Safety and Applied Nutrition, University of Maryland , College Park, Maryland
| | - Maria S Oei
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health , Bethesda, Maryland
| | - Catherine E Ovitt
- Center for Oral Biology and Department of Biomedical Genetics, University of Rochester , Rochester, New York
| | - Murat Sincan
- Office of the Clinical Director, National Institute of Dental and Craniofacial Research, National Institutes of Health , Bethesda, Maryland
| | - James E Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health , Bethesda, Maryland
| |
Collapse
|
29
|
Munemasa T, Mukaibo T, Kondo Y, Masaki C, Kusuda Y, Miyagi Y, Tsuka S, Hosokawa R, Nakamoto T. Salivary gland hypofunction in KK-A y type 2 diabetic mice. J Diabetes 2018; 10:18-27. [PMID: 28299899 DOI: 10.1111/1753-0407.12548] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/27/2017] [Accepted: 03/12/2017] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Hypofunction of different organs in the body is associated with diabetes, including in the oral cavity. Diabetes is often associated with xerostomia, but the underlying mechanism is not well characterized. Thus, the mechanisms underlying diabetes-induced xerostomia were investigated in this study in KK-A y mice as an experimental model of type 2 diabetes. METHODS The mechanisms involved in diabetes-induced xerostomia were investigated using the ex vivo glandular perfusion technique, histological analysis, and immunohistochemical and intracellular signaling analyses. RESULTS Ex vivo submandibular gland secretions from KK-Ay mice decreased by 30% following stimulation with 0.3 μmol/L carbachol (CCh), a cholinergic agonist. Acinar cell weight was comparable between KK-Ay and control mice, whereas duct cell weight was significantly greater in KK-Ay mice. Concentrations of Na+ and Cl- in the secreted saliva decreased significantly in KK-Ay mice, supporting the finding of increased ductal tissue in KK-Ay mice. Immunohistochemistry revealed no significant differences between KK-Ay and control mice in terms of the expression of Cl- and water channels, Na+ -K+ -2Cl- cotransporters, and membrane proteins critical for fluid secretion. Cellular signaling analysis revealed that the increase in [Ca2+ ]i in response to 0.3 μmol/L CCh was reduced by 30% in KK-Ay mice, although there was no significant difference in the thapsigargin (1.0 μmol/L)-induced increase in store-depleted calcium between KK-Ay and control mice. CONCLUSIONS These results demonstrate that submandibular fluid secretion is diminished in KK-Ay mice because of a diminished increase in [Ca2+ ]i . Duct cell weight increased in KK-Ay mice, possibly leading to increased ion reabsorption and thus decreased Na+ and Cl- concentrations in the secreted saliva.
Collapse
Affiliation(s)
- Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yuichiro Kusuda
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yuta Miyagi
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Tetsuji Nakamoto
- Department of Prosthodontics, Matsumoto Dental University, Nagano, Japan
| |
Collapse
|
30
|
Zeng M, Szymczak M, Ahuja M, Zheng C, Yin H, Swaim W, Chiorini JA, Bridges RJ, Muallem S. Restoration of CFTR Activity in Ducts Rescues Acinar Cell Function and Reduces Inflammation in Pancreatic and Salivary Glands of Mice. Gastroenterology 2017; 153. [PMID: 28634110 PMCID: PMC5623154 DOI: 10.1053/j.gastro.2017.06.011] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND & AIMS Sjögren's syndrome and autoimmune pancreatitis are disorders with decreased function of salivary, lacrimal glands, and the exocrine pancreas. Nonobese diabetic/ShiLTJ mice and mice transduced with the cytokine BMP6 develop Sjögren's syndrome and chronic pancreatitis and MRL/Mp mice are models of autoimmune pancreatitis. Cystic fibrosis transmembrane conductance regulator (CFTR) is a ductal Cl- channel essential for ductal fluid and HCO3- secretion. We used these models to ask the following questions: is CFTR expression altered in these diseases, does correction of CFTR correct gland function, and most notably, does correcting ductal function correct acinar function? METHODS We treated the mice models with the CFTR corrector C18 and the potentiator VX770. Glandular, ductal, and acinar cells damage, infiltration, immune cells and function were measured in vivo and in isolated duct/acini. RESULTS In the disease models, CFTR expression is markedly reduced. The salivary glands and pancreas are inflamed with increased fibrosis and tissue damage. Treatment with VX770 and, in particular, C18 restored salivation, rescued CFTR expression and localization, and nearly eliminated the inflammation and tissue damage. Transgenic overexpression of CFTR exclusively in the duct had similar effects. Most notably, the markedly reduced acinar cell Ca2+ signaling, Orai1, inositol triphosphate receptors, Aquaporin 5 expression, and fluid secretion were restored by rescuing ductal CFTR. CONCLUSIONS Our findings reveal that correcting ductal function is sufficient to rescue acinar cell function and suggests that CFTR correctors are strong candidates for the treatment of Sjögren's syndrome and pancreatitis.
Collapse
Affiliation(s)
- Mei Zeng
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD,North Sichuan Medical College, Fujiang Road, Nanchong, 637000, Sichuan, China
| | - Mitchell Szymczak
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - Malini Ahuja
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - Changyu Zheng
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - Hongen Yin
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - William Swaim
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - John A. Chiorini
- Molecular Physiology and Therapeutics Branch, NIH, National Institute of Dental and Craniofacial Research, Bethesda MD
| | - Robert J Bridges
- Department of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL
| | - Shmuel Muallem
- Molecular Physiology and Therapeutics Branch, National Institutes of Health, National Institute of Dental and Craniofacial Research, Bethesda, Maryland.
| |
Collapse
|
31
|
Progress in understanding mucus abnormalities in cystic fibrosis airways. J Cyst Fibros 2017; 17:S35-S39. [PMID: 28951068 DOI: 10.1016/j.jcf.2017.09.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 09/13/2017] [Accepted: 09/14/2017] [Indexed: 12/18/2022]
Abstract
Normal airways below the carina maintain an essentially sterile environment via a multi-pronged innate defence system that includes mucus clearance via mucociliary clearance and cough, multiple antimicrobials and cellular components including macrophages and neutrophils. In cystic fibrosis (CF), loss of CFTR function compromises these defences, and with present standard of care virtually all people with CF eventually develop mucus accumulation, plugging and chronic infections. This review focuses on how mucus is affected by CFTR loss.
Collapse
|
32
|
Felix CM, Lee S, Levin MH, Verkman AS. Pro-Secretory Activity and Pharmacology in Rabbits of an Aminophenyl-1,3,5-Triazine CFTR Activator for Dry Eye Disorders. Invest Ophthalmol Vis Sci 2017; 58:4506-4513. [PMID: 28873176 PMCID: PMC5584707 DOI: 10.1167/iovs.17-22525] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Purpose Pharmacological activation of ocular surface cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels is a potential pro-secretory approach to treat dry eye disorders. We previously reported the discovery of aminophenyl-1,3,5-triazines, one of which, N-methyl-N-phenyl-6-(2,2,3,3-tetrafluoropropoxy)-1,3,5-triazine-2,4-diamine (herein called CFTRact-K267), fully activated human wildtype CFTR with EC50 ∼ 30 nM and increased tear volume for 8 hours in mice. Here, functional and pharmacological studies of CFTRact-K267 were done in adult New Zealand white rabbits. Methods CFTR chloride conductance was measured in vivo by ocular surface potential differences and in ex vivo conjunctiva by short-circuit current. Tear volume was measured by the Schirmer tear test II and CFTRact-K267 pharmacokinetics and tissue distribution by liquid chromatography/mass spectrometry. Toxicity profile was studied for 28 days with twice-daily topical administration. Results Electrophysiological measurements in vivo and in ex vivo conjunctiva demonstrated CFTR activation by CFTRact-K267. A single topical dose of 3 nmol CFTRact-K267 increased tear production by >5 mm for 9 hours by the Schirmer tear test, with predicted therapeutic concentrations maintained in tear fluid. No tachyphylaxis was seen following 28-day twice-daily administration, and changes were not observed in corneal surface integrity or thickness, intraocular pressure, or ocular histology. At day 28, CFTRact-K267 was concentrated in the cornea and conjunctiva and was not detectable in blood or peripheral organs. Conclusions These studies support the development of CFTRact-K267 as a pro-secretory therapy for dry eye disorders.
Collapse
Affiliation(s)
- Christian M Felix
- Departments of Medicine and Physiology, University of California, San Francisco, California, United States
| | - Sujin Lee
- Departments of Medicine and Physiology, University of California, San Francisco, California, United States
| | - Marc H Levin
- Department of Ophthalmology, Palo Alto Medical Foundation, Palo Alto, California, United States
| | - Alan S Verkman
- Departments of Medicine and Physiology, University of California, San Francisco, California, United States
| |
Collapse
|
33
|
Marunaka Y. The Mechanistic Links between Insulin and Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Cl - Channel. Int J Mol Sci 2017; 18:ijms18081767. [PMID: 28805732 PMCID: PMC5578156 DOI: 10.3390/ijms18081767] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 07/31/2017] [Accepted: 08/10/2017] [Indexed: 12/30/2022] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel belongs to the ATP-binding cassette (ABC) transporter superfamily and regulates Cl− secretion in epithelial cells for water secretion. Loss-of-function mutations to the CFTR gene cause dehydrated mucus on the apical side of epithelial cells and increase the susceptibility of bacterial infection, especially in the airway and pulmonary tissues. Therefore, research on the molecular properties of CFTR, such as its gating mechanism and subcellular trafficking, have been intensively pursued. Dysregulated CFTR trafficking is one of the major pathological hallmarks in cystic fibrosis (CF) patients bearing missense mutations in the CFTR gene. Hormones that activate cAMP signaling, such as catecholamine, have been found to regulate the intracellular trafficking of CFTR. Insulin is one of the hormones that regulate cAMP production and promote trafficking of transmembrane proteins to the plasma membrane. The functional interactions between insulin and CFTR have not yet been clearly defined. In this review article, I review the roles of CFTR in epithelial cells, its regulatory role in insulin secretion, and a mechanism of CFTR regulation by insulin.
Collapse
Affiliation(s)
- Yoshinori Marunaka
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
- Department of Bio-Ionomics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
- Japan Institute for Food Education and Health, St. Agnes' University, Kyoto 602-8013, Japan.
| |
Collapse
|
34
|
Zhang J, Karimy JK, Delpire E, Kahle KT. Pharmacological targeting of SPAK kinase in disorders of impaired epithelial transport. Expert Opin Ther Targets 2017; 21:795-804. [PMID: 28679296 PMCID: PMC6081737 DOI: 10.1080/14728222.2017.1351949] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The mammalian SPS1-related proline/alanine-rich serine-threonine kinase SPAK (STK39) modulates ion transport across and between epithelial cells in response to environmental stimuli such osmotic stress and inflammation. Research over the last decade has established a central role for SPAK in the regulation of ion and water transport in the distal nephron, colonic crypts, and pancreatic ducts, and has implicated deregulated SPAK signaling in NaCl-sensitive hypertension, ulcerative colitis and Crohn's disease, and cystic fibrosis. Areas covered: We review recent advances in our understanding of the role of SPAK kinase in the regulation of epithelial transport. We highlight how SPAK signaling - including its upstream Cl- sensitive activators, the WNK kinases, and its downstream ion transport targets, the cation- Cl- cotransporters contribute to human disease. We discuss prospects for the pharmacotherapeutic targeting of SPAK kinase in specific human disorders that feature impaired epithelial homeostasis. Expert opinion: The development of novel drugs that antagonize the SPAK-WNK interaction, inhibit SPAK kinase activity, or disrupt SPAK kinase activation by interfering with its binding to MO25α/β could be useful adjuncts in essential hypertension, inflammatory colitis, and cystic fibrosis.
Collapse
Affiliation(s)
- Jinwei Zhang
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Hatherly Laboratory, Exeter, EX4 4PS, UK
| | - Jason K. Karimy
- Department of Neurosurgery, Yale School of Medicine, New Haven, CT 06510, USA
| | - Eric Delpire
- Department of Anesthesiolgy, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kristopher T. Kahle
- Departments of Neurosurgery, Pediatrics, and Cellular & Molecular Physiology; and Centers for Mendelian Genomics, Yale School of Medicine, New Haven, CT 06510, USA
| |
Collapse
|
35
|
Ji M, Park CK, Lee JW, Park KY, Son KH, Hong JH. Two Phase Modulation of [Formula: see text] Entry and Cl -/[Formula: see text] Exchanger in Submandibular Glands Cells by Dexmedetomidine. Front Physiol 2017; 8:86. [PMID: 28298895 PMCID: PMC5331071 DOI: 10.3389/fphys.2017.00086] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 01/30/2017] [Indexed: 12/15/2022] Open
Abstract
Dexmedetomidine (Dex), a highly selective α2-adrenoceptor agonist, attenuates inflammatory responses induced by lipopolysaccharide (LPS) and induces sedative and analgesic effects. Administration of Dex also reduces salivary secretion in human subjects and inhibits osmotic water permeability in rat cortical collecting ducts. However, little is known about the mechanisms underlying the effects of Dex on salivary glands fluid secretion. We demonstrated the α2-adrenoceptor expression in the basolateral membrane of mouse submandibular glands (SMG). To investigate fluid secretion upon treatment with Dex, we studied the effects of Dex on the activity of Na+-K+-2Cl- cotransporter1 (NKCC1) and Cl-/[Formula: see text] exchange (CBE), and on downstream pro-inflammatory cytokine expression in isolated primary mouse SMG cells. Dex acutely increased CBE activity and NKCC1-mediated and independent [Formula: see text] entry in SMG duct cells, and enhanced ductal fluid secretion in a sealed duct system. Dex showed differential effects on cholinergic/adrenergic stimulations and inflammatory mediators, histamine, and LPS, stimulations-induced Ca2+ in mouse SMG cells. Both, histamine- and LPS-induced intracellular Ca2+ increases were inhibited by Dex, whereas carbachol-stimulated Ca2+ signals were not. Long-lasting (2 h) treatment with Dex reduced CBE activity in SMG and in human submandibular glands (HSG) cells. Moreover, when isolated SMG cells were stimulated with Dex for 2 h, phosphodiesterase 4D (PDE4D) expression was enhanced. These results confirm the anti-inflammatory properties of Dex on LPS-mediated signaling. Further, Dex also inhibited mRNA expression of interleukin-6 and NADPH oxidase 4. The present study also showed that α2-adrenoceptor activation by Dex reduces salivary glands fluid secretion by increasing PDE4D expression, and subsequently reducing the concentration of cAMP. These findings reveal an interaction between the α2-adrenoceptor and PDE4D, which should be considered when using α2-adrenoceptor agonists as sedative or analgesics.
Collapse
Affiliation(s)
- Minjeong Ji
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon UniversityIncheon, South Korea
| | - Chul-Kyu Park
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon UniversityIncheon, South Korea
| | - Jin Woo Lee
- Department of Molecular Medicine, School of Medicine, Lee Gil Ya Cancer and Diabetes Institute, Gachon UniversityIncheon, South Korea
| | - Kook Yang Park
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon UniversityIncheon, South Korea
| | - Kuk Hui Son
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon UniversityIncheon, South Korea
| | - Jeong Hee Hong
- Department of Physiology, Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon UniversityIncheon, South Korea
| |
Collapse
|
36
|
Abstract
WNK kinases, along with their upstream regulators (CUL3/KLHL3) and downstream targets (the SPAK/OSR1 kinases and the cation-Cl- cotransporters [CCCs]), comprise a signaling cascade essential for ion homeostasis in the kidney and nervous system. Recent work has furthered our understanding of the WNKs in epithelial transport, cell volume homeostasis, and GABA signaling, and uncovered novel roles for this pathway in immune cell function and cell proliferation.
Collapse
Affiliation(s)
- Masoud Shekarabi
- Department of Neuroscience, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Jinwei Zhang
- Departments of Neurosurgery, Centers for Mendelian Genomics, Yale School of Medicine, New Haven, CT 06477, USA; MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Arjun R Khanna
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurosurgery, Harvard Medical School, Boston, MA 02115, USA
| | - David H Ellison
- Division of Nephrology & Hypertension, Department of Medicine, Oregon Health & Science University, Portland, Oregon 97239, USA; VA Portland Health Care System, Portland, OR 97239, USA
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Kristopher T Kahle
- Departments of Neurosurgery, Pediatrics, and Cellular & Molecular Physiology, Centers for Mendelian Genomics, Yale School of Medicine, New Haven, CT 06477, USA.
| |
Collapse
|
37
|
Capra JP, Eskelinen SM. MDCK cells are capable of water secretion and reabsorption in response to changes in the ionic environment. Can J Physiol Pharmacol 2017; 95:72-83. [DOI: 10.1139/cjpp-2016-0051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A prerequisite for tissue electrolyte homeostasis is highly regulated ion and water transport through kidney or intestinal epithelia. In the present work, we monitored changes in the cell and luminal volumes of type II Madin-Darby canine kidney (MDCK) cells grown in a 3D environment in response to drugs, or to changes in the composition of the basal extracellular fluid. Using fluorescent markers and high-resolution spinning disc confocal microscopy, we could show that lack of sodium and potassium ions in the basal fluid (tetramethylammonium chloride (TMACl) buffer) induces a rapid increase in the cell and luminal volumes. This transepithelial water flow could be regulated by inhibitors and agonists of chloride channels. Hence, the driving force for the transepithelial water flow is chloride secretion, stimulated by hyperpolarization. Chloride ion depletion of the basal fluid (using sodium gluconate buffer) induces a strong reduction in the lumen size, indicating reabsorption of water from the lumen to the basal side. Lumen size also decreased following depolarization of the cell interior by rendering the membrane permeable to potassium. Hence, MDCK cells are capable of both absorption and secretion of chloride ions and water; negative potential within the lumen supports secretion, while depolarizing conditions promote reabsorption.
Collapse
Affiliation(s)
- Janne P. Capra
- Biocenter Oulu and the Institute of Diagnostics, University of Oulu, Oulu, Finland
- Biocenter Oulu and the Institute of Diagnostics, University of Oulu, Oulu, Finland
| | - Sinikka M. Eskelinen
- Biocenter Oulu and the Institute of Diagnostics, University of Oulu, Oulu, Finland
- Biocenter Oulu and the Institute of Diagnostics, University of Oulu, Oulu, Finland
| |
Collapse
|
38
|
Concepcion AR, Feske S. Regulation of epithelial ion transport in exocrine glands by store-operated Ca 2+ entry. Cell Calcium 2016; 63:53-59. [PMID: 28027799 DOI: 10.1016/j.ceca.2016.12.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 12/17/2016] [Indexed: 02/08/2023]
Abstract
Store-operated Ca2+ entry (SOCE) is a conserved mechanism of Ca2+ influx that regulates Ca2+ signaling in many cell types. SOCE is activated by depletion of endoplasmic reticulum (ER) Ca2+ stores in response to physiological agonist stimulation. After it was first postulated by J.W. Putney Jr. in 1986, SOCE has been described in a large number of non-excitable cell types including secretory cells of different exocrine glands. Here we discuss the mechanisms by which SOCE controls salt and fluid secretion in exocrine glands, with a special focus on eccrine sweat glands. In sweat glands, SOCE plays an important, non-redundant role in regulating the function of Ca2+-activated Cl- channels (CaCC), Cl- secretion and sweat production. In the absence of key regulators of SOCE such as the CRAC channel pore subunit ORAI1 and its activator STIM1, the Ca2+-activated chloride channel TMEM16A is inactive and fails to secrete Cl-, resulting in anhidrosis in mice and human patients.
Collapse
Affiliation(s)
- Axel R Concepcion
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA.
| |
Collapse
|
39
|
Kamikawa A, Ichii O, Sakazaki J, Ishikawa T. Ca2+-activated Cl− channel currents in mammary secretory cells from lactating mouse. Am J Physiol Cell Physiol 2016; 311:C808-C819. [DOI: 10.1152/ajpcell.00050.2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 08/19/2016] [Indexed: 11/22/2022]
Abstract
The Cl− secretion via Ca2+-activated Cl− channel (CaCC) is critical for fluid secretion in exocrine glands like the salivary gland. Also in the mammary gland, it has been hypothesized that CaCC plays an important role in the secretion of Cl− and aqueous phase of milk. However, there has been no evidence for the functional expression of CaCC in native mammary secretory (MS) cells of lactating animals. We therefore assessed membrane current in MS cells that were freshly isolated from lactating mice using whole cell patch-clamp techniques. In MS cells, we detected CaCC current that exhibited the following characteristics: 1) Ca2+-dependent activation at the concentrations of submicromolar range; 2) voltage-dependent activation; 3) slow kinetics for activation and deactivation; 4) outward rectification of the steady-state current; 5) anion permeability in the sequence of I− > NO3− > Br− > Cl− >> glutamate; 6) inhibition by Cl− channel blockers (niflumic acid, DIDS, and CaCCinh-A01). These characteristics of native CaCC current were similar to reported characteristics of heterologously expressed TMEM16A. RT-PCR analyses showed the expression of multiple CaCC channels including TMEM16A, Best1, and Best3 in the mammary glands of lactating mice. Immunohistochemical staining revealed the localization of TMEM16A protein at the apical membrane of the MS cells. Collectively, our data strongly suggest that MS cells functionally express CaCC, which is at least partly constituted by TMEM16A. The CaCC such as TMEM16A at the apical membrane of the MS cells may influence the quantity and/or quality of milk.
Collapse
Affiliation(s)
- Akihiro Kamikawa
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan; and
| | - Osamu Ichii
- Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Junpei Sakazaki
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan; and
| | - Toru Ishikawa
- Department of Basic Veterinary Medicine, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan; and
| |
Collapse
|
40
|
Saint-Criq V, Gray MA. Role of CFTR in epithelial physiology. Cell Mol Life Sci 2016; 74:93-115. [PMID: 27714410 PMCID: PMC5209439 DOI: 10.1007/s00018-016-2391-y] [Citation(s) in RCA: 252] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 12/20/2022]
Abstract
Salt and fluid absorption and secretion are two processes that are fundamental to epithelial function and whole body fluid homeostasis, and as such are tightly regulated in epithelial tissues. The CFTR anion channel plays a major role in regulating both secretion and absorption in a diverse range of epithelial tissues, including the airways, the GI and reproductive tracts, sweat and salivary glands. It is not surprising then that defects in CFTR function are linked to disease, including life-threatening secretory diarrhoeas, such as cholera, as well as the inherited disease, cystic fibrosis (CF), one of the most common life-limiting genetic diseases in Caucasian populations. More recently, CFTR dysfunction has also been implicated in the pathogenesis of acute pancreatitis, chronic obstructive pulmonary disease (COPD), and the hyper-responsiveness in asthma, underscoring its fundamental role in whole body health and disease. CFTR regulates many mechanisms in epithelial physiology, such as maintaining epithelial surface hydration and regulating luminal pH. Indeed, recent studies have identified luminal pH as an important arbiter of epithelial barrier function and innate defence, particularly in the airways and GI tract. In this chapter, we will illustrate the different operational roles of CFTR in epithelial function by describing its characteristics in three different tissues: the airways, the pancreas, and the sweat gland.
Collapse
Affiliation(s)
- Vinciane Saint-Criq
- Epithelial Research Group, Institute for Cell and Molecular Biosciences, University Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH UK
| | - Michael A. Gray
- Epithelial Research Group, Institute for Cell and Molecular Biosciences, University Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH UK
| |
Collapse
|
41
|
Ambudkar IS. Calcium signalling in salivary gland physiology and dysfunction. J Physiol 2016; 594:2813-24. [PMID: 26592972 PMCID: PMC4887685 DOI: 10.1113/jp271143] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 10/31/2015] [Indexed: 01/29/2023] Open
Abstract
Studies over the past four decades have established that Ca(2+) is a critical factor in control of salivary gland function and have led to identification of the critical components of this process. The major ion transport mechanisms and ion channels that are involved in fluid secretion have also been established. The key event in activation of fluid secretion is an increase in [Ca(2+) ]i triggered by inositol 1,4,5-trisphosphate (IP3 )-induced release of Ca(2+) from ER via the IP3 receptor (IP3 R). IP3 Rs determine the site of initiation and the pattern of the [Ca(2+) ]i signal in the cell. However, Ca(2+) entry into the cell is required to sustain the elevation of [Ca(2+) ]i and fluid secretion and is mediated by the store-operated Ca(2+) entry (SOCE) mechanism. Orai1, TRPC1, TRPC3 and STIM1 have been identified as critical components of SOCE in these cells. Cells finely tune the generation and amplification of [Ca(2+) ]i signals for regulation of cell function. An important emerging area is the concept that unregulated [Ca(2+) ]i signals in cells can directly cause cell damage, dysfunction and disease. Alternatively, aberrant [Ca(2+) ]i signals can also amplify and increase the rates of cell damage. Such defects in Ca(2+) signalling have been described in salivary glands in conjunction with radiation-induced loss of salivary gland function as well as in the salivary defects associated with the autoimmune exocrinopathy Sjögren's syndrome. Such defects have been associated with altered function or expression of key Ca(2+) signalling components, such as STIM proteins and TRP channels. These studies offer new avenues for examining the mechanisms underlying the disease and development of novel clinical targets and therapeutic strategies.
Collapse
Affiliation(s)
- Indu S Ambudkar
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, MD, 20892, USA
| |
Collapse
|
42
|
Chun H, Cho H, Choi J, Lee J, Kim SM, Kim H, Oh U. Protons inhibit anoctamin 1 by competing with calcium. Cell Calcium 2015; 58:431-41. [DOI: 10.1016/j.ceca.2015.06.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 06/13/2015] [Accepted: 06/28/2015] [Indexed: 01/30/2023]
|
43
|
Abstract
The human exocrine pancreas consists of 2 main cell types: acinar and ductal cells. These exocrine cells interact closely to contribute to the secretion of pancreatic juice. The most important ion in terms of the pancreatic ductal secretion is HCO3. In fact, duct cells produce an alkaline fluid that may contain up to 140 mM NaHCO3, which is essential for normal digestion. This article provides an overview of the basics of pancreatic ductal physiology and pathophysiology. In the first part of the article, we discuss the ductal electrolyte and fluid transporters and their regulation. The central role of cystic fibrosis transmembrane conductance regulator (CFTR) is highlighted, which is much more than just a Cl channel. We also review the role of pancreatic ducts in severe debilitating diseases such as cystic fibrosis (caused by various genetic defects of cftr), pancreatitis, and diabetes mellitus. Stimulation of ductal secretion in cystic fibrosis and pancreatitis may have beneficial effects in their treatment.
Collapse
|
44
|
Cacace V, Kusnier CF, Fischbarg J. RETRACTED ARTICLE: Net Fluorescein Flux Across Corneal Endothelium Suggests Fluid Transport is Driven by Electroosmosis. J Membr Biol 2015; 249:197. [PMID: 26423751 PMCID: PMC4851691 DOI: 10.1007/s00232-015-9849-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 09/18/2015] [Indexed: 11/30/2022]
Affiliation(s)
- V Cacace
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina
| | - C F Kusnier
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina
| | - J Fischbarg
- ININCA, Conicet, Marcelo T. de Alvear 2270, CP 1122AAJ, Buenos Aires, Argentina.
| |
Collapse
|
45
|
Hegyesi O, Földes A, Bori E, Németh Z, Barabás J, Steward MC, Varga G. Evidence for Active Electrolyte Transport by Two-Dimensional Monolayers of Human Salivary Epithelial Cells. Tissue Eng Part C Methods 2015. [PMID: 26200762 DOI: 10.1089/ten.tec.2014.0614] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Functional reconstruction of lost tissue by regenerative therapy of salivary glands would be of immense benefit following radiotherapy or in the treatment of Sjogren's syndrome. The purpose of this study was to develop primary cultures of human salivary gland cells as potential regenerative resources and to characterize their acinar/ductal phenotype using electrophysiological measurements of ion transport. Human salivary gland cultures were prepared either from adherent submandibular gland cells (huSMG) or from mixed adherent and nonadherent cells (PTHSG) and were cultivated in Hepato-STIM or minimum essential medium (MEM). Expression of key epithelial marker proteins was determined by quantitative reverse transcription polymerase chain reaction (RT-PCR). Transepithelial electrical resistance (TER) was monitored following seeding the cells on Transwell membranes. Transepithelial ion transport was estimated by short-circuit current (Isc) measurements in an Ussing chamber. Both huSMG and PTHSG cells showed epithelial characteristics when cultivated in Hepato-STIM, while fibroblast-like elements dominated in MEM. Compared to intact tissue, cultivation of the cells resulted in substantial decreases in AQP5 and NKCC1 expression and moderate increases in claudin-1 and ENaC expression. Both cultures achieved high TER and transepithelial electrolyte movement in Hepato-STIM, but not in MEM. The Isc was substantially reduced by basolateral Cl(-) and bicarbonate withdrawal, indicating the involvement of basolateral-to-apical anion transport, and by the blockade of apical ENaC by amiloride, indicating the involvement of apical-to-basolateral Na(+) transport. An almost complete inhibition was observed following simultaneous ENaC block and withdrawal of the two anions. Isc was enhanced by either apical adenosine triphosphate (ATP) or basolateral carbachol application, but not by forskolin, confirming the expected role of Ca(2+)-activated regulatory pathways in electrolyte secretion. Inhibition of basolateral NKCC1 by bumetanide reduced the response to ATP, indicating the active involvement of this transporter in Cl(-) secretion. In conclusion, we have demonstrated that both PTHSG and huSMG primary cultures cultivated in Hepato-STIM form two-dimensional monolayers in vitro on permeable supports and achieve active vectorial transepithelial electrolyte transport. The presence of both basolateral-to-apical anion fluxes and an apical-to-basolateral Na(+) flux indicates both acinar and ductal characteristics. With further refinement, this model should provide a firm basis for new interventions to correct salivary gland dysfunction.
Collapse
Affiliation(s)
- Orsolya Hegyesi
- 1 Department of Oral Biology, Semmelweis University , Budapest, Hungary
| | - Anna Földes
- 1 Department of Oral Biology, Semmelweis University , Budapest, Hungary
| | - Erzsébet Bori
- 1 Department of Oral Biology, Semmelweis University , Budapest, Hungary
| | - Zsolt Németh
- 2 Department of Oro-Maxillofacial Surgery and Stomatology, Semmelweis University , Budapest, Hungary
| | - József Barabás
- 2 Department of Oro-Maxillofacial Surgery and Stomatology, Semmelweis University , Budapest, Hungary
| | - Martin C Steward
- 3 Faculty of Life Sciences, University of Manchester , Manchester, United Kingdom
| | - Gábor Varga
- 1 Department of Oral Biology, Semmelweis University , Budapest, Hungary
| |
Collapse
|
46
|
Varga G, Kerémi B, Bori E, Földes A. Function and repair of dental enamel - Potential role of epithelial transport processes of ameloblasts. Pancreatology 2015; 15:S55-60. [PMID: 25747281 DOI: 10.1016/j.pan.2015.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/28/2015] [Indexed: 12/11/2022]
Abstract
The hardest mammalian tissue, dental enamel is produced by ameloblasts, which are electrolyte-transporting epithelial cells. Although the end product is very different, they show many similarities to transporting epithelia of the pancreas, salivary glands and kidney. Enamel is produced in a multi-step epithelial secretory process that features biomineralization which is an interplay of secreted ameloblast specific proteins and the time-specific transport of minerals, protons and bicarbonate. First, "secretory" ameloblasts form the entire thickness of the enamel layer, but with low mineral content. Then they differentiate into "maturation" ameloblasts, which remove organic matrix from the enamel and in turn further build up hydroxyapatite crystals. The protons generated by hydroxyapatite formation need to be buffered, otherwise enamel will not attain full mineralization. Buffering requires a tight pH regulation and secretion of bicarbonate by ameloblasts. The whole process has been the focus of many immunohistochemical and gene knock-out studies, but, perhaps surprisingly, no functional data existed for mineral ion transport by ameloblasts. However, recent studies including ours provided a better insight for molecular mechanism of mineral formation. The secretory regulation is not completely known as yet, but its significance is crucial. Impairing regulation retards or prevents completion of enamel mineralization and results in the development of hypomineralized enamel that easily erodes after dental eruption. Factors that impair this function are fluoride and disruption of pH regulators. Revealing these factors may eventually lead to the treatment of enamel hypomineralization related to genetic or environmentally induced malformation.
Collapse
Affiliation(s)
- Gábor Varga
- Department of Oral Biology, Semmelweis University, Budapest, Hungary.
| | - Beáta Kerémi
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Erzsébet Bori
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| | - Anna Földes
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
| |
Collapse
|
47
|
Sahara Y, Horie S, Fukami H, Goto-Matsumoto N, Nakanishi-Matsui M. Functional roles of V-ATPase in the salivary gland. J Oral Biosci 2015. [DOI: 10.1016/j.job.2014.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
48
|
Sun H, Niisato N, Inui T, Marunaka Y. Insulin is involved in transcriptional regulation of NKCC and the CFTR Cl(-) channel through PI3K activation and ERK inactivation in renal epithelial cells. J Physiol Sci 2014; 64:433-43. [PMID: 25239597 PMCID: PMC10717268 DOI: 10.1007/s12576-014-0338-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 08/31/2014] [Indexed: 01/26/2023]
Abstract
It is is well known that insulin stimulates glucose transport and epithelial Na(+) channel (ENaC)-mediated Na(+) reabsorption; however, the action of insulin on Cl(-) secretion is not fully understood. In this study, we investigated the action of insulin on Na(+)-K(+)-2Cl(-) cotransporter (NKCC)-mediated Cl(-) secretion in epithelial A6 cells. Interestingly, insulin treatment remarkably enhanced the forskolin-stimulated Cl(-) secretion associated with an increase in apical Cl(-) conductance by upregulating mRNA expression of both CFTR and NKCC, although insulin treatment alone had no effect on the basal Cl(-) secretion or apical Cl(-) conductance without forskolin application. We next elucidated a role of phosphoinositide 3-kinase (PI3K) in the insulin-induced enhancement of the Cl(-) secretion, since insulin actually activated PI3K, resulting in activation of Akt, a downstream molecule of PI3K. LY294002 (a PI3K inhibitor) reduced the Cl(-) secretion by suppressing mRNA expression of NKCC, whereas insulin still had a stimulatory action on mRNA expression of CFTR even in the presence of LY294002. On the other hand, we found that a MEK inhibitor (PD98059) further enhanced the insulin-stimulated CFTR mRNA expression and the Cl(-) secretion in forskolin-stimulated A6 cells and that insulin induced slight, transient activation of ERK followed by significant inactivation of ERK. These observations suggest that: (1) insulin respectively upregulates mRNA expression of NKCC and CFTR through activation of PI3K and inactivation of ERK; (2) insulin signals on mRNA expression of NKCC and CFTR are not enough to stimulate transepithelial Cl(-) secretion, but enhance the stimulatory action of cAMP on transepithelial Cl(-) secretion.
Collapse
Affiliation(s)
- Hongxin Sun
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
| | - Naomi Niisato
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
- Japan Institute for Food Education and Health, St. Agnes’ University, Kyoto, 602-8013 Japan
| | - Toshio Inui
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
- Department of Bio-Ionomics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
- Saisei Mirai Clinics, Moriguchi, 570-0012 Japan
| | - Yoshinori Marunaka
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
- Department of Bio-Ionomics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566 Japan
- Japan Institute for Food Education and Health, St. Agnes’ University, Kyoto, 602-8013 Japan
| |
Collapse
|
49
|
Distinct action of flavonoids, myricetin and quercetin, on epithelial Cl⁻ secretion: useful tools as regulators of Cl⁻ secretion. BIOMED RESEARCH INTERNATIONAL 2014; 2014:902735. [PMID: 24818160 PMCID: PMC4000985 DOI: 10.1155/2014/902735] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 03/06/2014] [Accepted: 03/10/2014] [Indexed: 01/01/2023]
Abstract
Epithelial Cl− secretion plays important roles in water secretion preventing bacterial/viral infection and regulation of body fluid. We previously suggested that quercetin would be a useful compound for maintaining epithelial Cl− secretion at a moderate level irrespective of cAMP-induced stimulation. However, we need a compound that stimulates epithelial Cl− secretion even under cAMP-stimulated conditions, since in some cases epithelial Cl− secretion is not large enough even under cAMP-stimulated conditions. We demonstrated that quercetin and myricetin, flavonoids, stimulated epithelial Cl− secretion under basal conditions in epithelial A6 cells. We used forskolin, which activates adenylyl cyclase increasing cytosolic cAMP concentrations, to study the effects of quercetin and myricetin on cAMP-stimulated epithelial Cl− secretion. In the presence of forskolin, quercetin diminished epithelial Cl− secretion to a level similar to that with quercetin alone without forskolin. Conversely, myricetin further stimulated epithelial Cl− secretion even under forskolin-stimulated conditions. This suggests that the action of myricetin is via a cAMP-independent pathway. Therefore, myricetin may be a potentially useful compound to increase epithelial Cl− secretion under cAMP-stimulated conditions. In conclusion, myricetin would be a useful compound for prevention from bacterial/viral infection even under conditions that the amount of water secretion driven by cAMP-stimulated epithelial Cl− secretion is insufficient.
Collapse
|
50
|
cAMP and Ca²⁺ signaling in secretory epithelia: crosstalk and synergism. Cell Calcium 2014; 55:385-93. [PMID: 24613710 DOI: 10.1016/j.ceca.2014.01.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 01/29/2014] [Accepted: 01/30/2014] [Indexed: 12/15/2022]
Abstract
The Ca(2+) and cAMP/PKA pathways are the primary signaling systems in secretory epithelia that control virtually all secretory gland functions. Interaction and crosstalk in Ca(2+) and cAMP signaling occur at multiple levels to control and tune the activity of each other. Physiologically, Ca(2+) and cAMP signaling operate at 5-10% of maximal strength, but synergize to generate the maximal response. Although synergistic action of the Ca(2+) and cAMP signaling is the common mode of signaling and has been known for many years, we know very little of the molecular mechanism and mediators of the synergism. In this review, we discuss crosstalk between the Ca(2+) and cAMP signaling and the function of IRBIT (IP3 receptors binding protein release with IP3) as a third messenger that mediates the synergistic action of the Ca(2+) and cAMP signaling.
Collapse
|