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Takahashi Y, Munemasa T, Nodai T, Mukaibo T, Kondo Y, Masaki C, Hosokawa R. Application of anti-vascular endothelial growth factor antibody restores the function of saliva secretion in a type 2 diabetes mouse model. J Oral Biosci 2024:S1349-0079(24)00148-8. [PMID: 38944342 DOI: 10.1016/j.job.2024.06.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 06/25/2024] [Accepted: 06/26/2024] [Indexed: 07/01/2024]
Abstract
OBJECTIVES Xerostomia, a common complication of type 2 diabetes, leads to an increased risk of caries, dysphagia, and dysgeusia. Although anti-vascular endothelial growth factor (VEGF) antibodies, such as ranibizumab (RBZ), have been used to treat diabetic retinopathy, their effects on the salivary glands are unknown. This study evaluated the effects of RBZ on salivary glands to reduce inflammation and restore salivary function in a mouse model of type 2 diabetes. METHODS Male KK-Ay mice with type 2 diabetes (10-12 weeks old) were used. The diabetes mellitus (DM) group received phosphate-buffered saline, while the DM + RBZ group received an intraperitoneal administration of RBZ (100 μg/kg) 24 h before the experiment. RESULTS Ex vivo perfusion experiments showed a substantial increase in salivary secretion from the submandibular gland (SMG) in the DM + RBZ group. In addition, the mRNA expression levels of TNF-α and IL-1β were considerably lower in this group. In contrast, those of aquaporin 5 were substantially higher in the DM + RBZ group, as revealed by quantitative reverse transcription PCR. Furthermore, the number of lymphocyte infiltration spots in the SMG was notably lower in the DM + RBZ group. Finally, intracellular Ca2+ signaling in acinar cells was considerably higher in the DM + RBZ group than that in the DM group. CONCLUSION Treating a type 2 diabetic mouse model with RBZ restored salivary secretion through its anti-inflammatory effects.
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Affiliation(s)
- Yusuke Takahashi
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan.
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
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Muñoz M, Acevedo A, Ovitt CE, Luitje ME, Maruyama EO, Catalán MA. CFTR expression in human salivary gland acinar cells. Am J Physiol Cell Physiol 2024; 326:C742-C748. [PMID: 38284125 PMCID: PMC11193460 DOI: 10.1152/ajpcell.00549.2023] [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: 10/17/2023] [Revised: 01/08/2024] [Accepted: 01/20/2024] [Indexed: 01/30/2024]
Abstract
The key role of CFTR in secretory epithelia has been extensively documented. Additionally, CFTR plays a significant role in ion absorption in exocrine glands, including salivary and sweat glands. Most of the knowledge about CFTR expression comes from animal models such as the mouse or the rat, but there is limited information about CFTR expression in human tissues. In the present study, we assessed the expression of CFTR in human submandibular and parotid glands. Consistent with findings in rodent salivary glands, our immunolocalization studies show that CFTR is expressed in duct cells. However, CFTR expression in human salivary glands differs from that in rodents, as immunolocalization and single-cell RNA sequencing analysis from a previous study performed in the human parotid gland revealed the presence of CFTR protein and transcripts within a distinct cell cluster. Based on cell marker expression, this cluster corresponds to acinar cells. To obtain functional evidence supporting CFTR expression, we isolated human parotid acinar cells through collagenase digestion. Acinar cells displayed an anion conductance that was activated in response to cAMP-increasing agents and was effectively blocked by CFTRInh172, a known CFTR blocker. This study provides novel evidence of CFTR expression within acinar cells of human salivary glands. This finding challenges the established model positioning CFTR exclusively in duct cells from exocrine glands.NEW & NOTEWORTHY This study addresses the uncertainty about the impact of CFTR on human salivary gland function. We found CFTR transcripts in a subset of duct cells known as ionocytes, as well as in acinar cells. Isolated human parotid acinar cells exhibited Cl- conductance consistent with CFTR activity. This marks the first documented evidence of functional CFTR expression in human salivary gland acinar cells.
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Affiliation(s)
- Manuel Muñoz
- Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile
| | - Alejandro Acevedo
- Instituto de Nutrición y Tecnología de los Alimentos, Universidad de Chile, Santiago, Chile
| | - Catherine E Ovitt
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States
| | - Martha E Luitje
- Department of Otolaryngology, University of Rochester Medical Center, Rochester, New York, United States
| | - Eri O Maruyama
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States
| | - Marcelo A Catalán
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
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Arreola J, Pérez-Cornejo P, Segura-Covarrubias G, Corral-Fernández N, León-Aparicio D, Guzmán-Hernández ML. Function and Regulation of the Calcium-Activated Chloride Channel Anoctamin 1 (TMEM16A). Handb Exp Pharmacol 2024; 283:101-151. [PMID: 35768554 DOI: 10.1007/164_2022_592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Various human tissues express the calcium-activated chloride channel Anoctamin 1 (ANO1), also known as TMEM16A. ANO1 allows the passive chloride flux that controls different physiological functions ranging from muscle contraction, fluid and hormone secretion, gastrointestinal motility, and electrical excitability. Overexpression of ANO1 is associated with pathological conditions such as hypertension and cancer. The molecular cloning of ANO1 has led to a surge in structural, functional, and physiological studies of the channel in several tissues. ANO1 is a homodimer channel harboring two pores - one in each monomer - that work independently. Each pore is activated by voltage-dependent binding of two intracellular calcium ions to a high-affinity-binding site. In addition, the binding of phosphatidylinositol 4,5-bisphosphate to sites scattered throughout the cytosolic side of the protein aids the calcium activation process. Furthermore, many pharmacological studies have established ANO1 as a target of promising compounds that could treat several illnesses. This chapter describes our current understanding of the physiological roles of ANO1 and its regulation under physiological conditions as well as new pharmacological compounds with potential therapeutic applications.
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Affiliation(s)
- Jorge Arreola
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico.
| | - Patricia Pérez-Cornejo
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Guadalupe Segura-Covarrubias
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
| | - Nancy Corral-Fernández
- Department of Physiology and Biophysics, School of Medicine of Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Daniel León-Aparicio
- Physics Institute, Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
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Cong X, Mao XD, Wu LL, Yu GY. The role and mechanism of tight junctions in the regulation of salivary gland secretion. Oral Dis 2024; 30:3-22. [PMID: 36825434 DOI: 10.1111/odi.14549] [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: 12/07/2022] [Revised: 01/27/2023] [Accepted: 02/21/2023] [Indexed: 02/25/2023]
Abstract
Tight junctions (TJs) are cell-cell interactions that localize at the most apical portion of epithelial/endothelial cells. One of the predominant functions of TJs is to regulate material transport through paracellular pathway, which serves as a selective barrier. In recent years, the expression and function of TJs in salivary glands has attracted great interest. The characteristics of multiple salivary gland TJ proteins have been identified. During salivation, the activation of muscarinic acetylcholine receptor and transient receptor potential vanilloid subtype 1, as well as other stimuli, promote the opening of acinar TJs by inducing internalization of TJs, thereby contributing to increased paracellular permeability. Besides, endothelial TJs are also redistributed with leakage of blood vessels in cholinergic-stimulated submandibular glands. Furthermore, under pathological conditions, such as Sjögren's syndrome, diabetes mellitus, immunoglobulin G4-related sialadenitis, and autotransplantation, the integrity and barrier function of TJ complex are impaired and may contribute to hyposalivation. Moreover, in submandibular glands of Sjögren's syndrome mouse model and patients, the endothelial barrier is disrupted and involved in hyposecretion and lymphocytic infiltration. These findings enrich our understanding of the secretory mechanisms that link the importance of epithelial and endothelial TJ functions to salivation under both physiological and pathophysiological conditions.
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Affiliation(s)
- Xin Cong
- Center for Salivary Gland Diseases, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
- Department of Physiology and Pathophysiology, Peking University School of Basic Sciences, Beijing, China
| | - Xiang-Di Mao
- Center for Salivary Gland Diseases, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
- Department of Physiology and Pathophysiology, Peking University School of Basic Sciences, Beijing, China
| | - Li-Ling Wu
- Center for Salivary Gland Diseases, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
- Department of Physiology and Pathophysiology, Peking University School of Basic Sciences, Beijing, China
| | - Guang-Yan Yu
- Center for Salivary Gland Diseases, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, China
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5
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Li K, Wang J, Du N, Sun Y, Sun Q, Yin W, Li H, Meng L, Liu X. Salivary microbiome and metabolome analysis of severe early childhood caries. BMC Oral Health 2023; 23:30. [PMID: 36658579 PMCID: PMC9850820 DOI: 10.1186/s12903-023-02722-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/05/2023] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Severe early childhood caries (SECC) is an inflammatory disease with complex pathology. Although changes in the oral microbiota and metabolic profile of patients with SECC have been identified, the salivary metabolites and the relationship between oral bacteria and biochemical metabolism remains unclear. We aimed to analyse alterations in the salivary microbiome and metabolome of children with SECC as well as their correlations. Accordingly, we aimed to explore potential salivary biomarkers in order to gain further insight into the pathophysiology of dental caries. METHODS We collected 120 saliva samples from 30 children with SECC and 30 children without caries. The microbial community was identified through 16S ribosomal RNA (rRNA) gene high-throughput sequencing. Additionally, we conducted non-targeted metabolomic analysis through ultra-high-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry to determine the relative metabolite levels and their correlation with the clinical caries status. RESULTS There was a significant between-group difference in 8 phyla and 32 genera in the microbiome. Further, metabolomic and enrichment analyses revealed significantly altered 32 salivary metabolites in children with dental caries, which involved pathways such as amino acid metabolism, pyrimidine metabolism, purine metabolism, ATP-binding cassette transporters, and cyclic adenosine monophosphate signalling pathway. Moreover, four in vivo differential metabolites (2-benzylmalate, epinephrine, 2-formaminobenzoylacetate, and 3-Indoleacrylic acid) might be jointly applied as biomarkers (area under the curve = 0.734). Furthermore, the caries status was correlated with microorganisms and metabolites. Additionally, Spearman's correlation analysis of differential microorganisms and metabolites revealed that Veillonella, Staphylococcus, Neisseria, and Porphyromonas were closely associated with differential metabolites. CONCLUSION This study identified different microbial communities and metabolic profiles in saliva, which may be closely related to caries status. Our findings could inform future strategies for personalized caries prevention, detection, and treatment.
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Affiliation(s)
- Kai Li
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Jinmei Wang
- grid.256883.20000 0004 1760 8442Department of Prosthodontics, Hospital of Stomatology Hebei Medical University, Hebei Medical University, Shijiazhuang, China
| | - Ning Du
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Yanjie Sun
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Qi Sun
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Weiwei Yin
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Huiying Li
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
| | - Lingqiang Meng
- grid.256883.20000 0004 1760 8442Department of Prosthodontics, Hospital of Stomatology Hebei Medical University, Hebei Medical University, Shijiazhuang, China
| | - Xuecong Liu
- grid.256883.20000 0004 1760 8442Department of Stomatology, Children’s Hospital of Hebei Province, Hebei Medical University, Shijiazhuang, China
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Chibly AM, Aure MH, Patel VN, Hoffman MP. Salivary Gland Function, Development and Regeneration. Physiol Rev 2022; 102:1495-1552. [PMID: 35343828 DOI: 10.1152/physrev.00015.2021] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Salivary glands produce and secrete saliva, which is essential for maintaining oral health and overall health. Understanding both the unique structure and physiological function of salivary glands, as well as how they are affected by disease and injury will direct the development of therapy to repair and regenerate them. Significant recent advances, particularly in the OMICS field, increase our understanding of how salivary glands develop at the cellular, molecular and genetic levels; the signaling pathways involved, the dynamics of progenitor cell lineages in development, homeostasis and regeneration and the role of the extracellular matrix microenvironment. These provide a template for cell and gene therapies as well as bioengineering approaches to repair or regenerate salivary function.
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Affiliation(s)
- Alejandro Martinez Chibly
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Marit H Aure
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Vaishali N Patel
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Matthew Philip Hoffman
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
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7
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Yamada M, Masaki C, Mukaibo T, Munemasa T, Nodai T, Kondo Y, Hosokawa R. Altered Rheological Properties of Saliva with Aging in Mouse Sublingual Gland. J Dent Res 2022; 101:942-950. [PMID: 35238237 DOI: 10.1177/00220345221076071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mucin in saliva plays a critical role in the hydration and lubrication of the oral mucosa by retaining water molecules, and its impaired function may be associated with hyposalivation-independent xerostomia. Age-dependent effects on salivary gland function and rheological properties of secreted saliva are not fully understood as aging is a complex and multifactorial process. We aimed to evaluate age-related changes in the rheological properties of saliva and elucidate the underlying mechanism. We performed ex vivo submandibular gland (SMG) and sublingual gland (SLG) perfusion experiments to collect saliva from isolated glands of young (12 wk old) and aged (27 mo old) female C57BL/6J mice and investigate the rheological properties by determining the spinnbarkeit (viscoelasticity). While fluid secretion was comparable in SMG and SLG of both mice, spinnbarkeit showed a significant decrease in SLG saliva of aged mice than that of young mice. There were no significant differences in GalNAc concentration between young and aged SLG saliva. Liquid chromatography/tandem mass spectrometry analysis of SLG saliva revealed that (Hex)1 (HexNAc)1 (NeuAc)1 at m/z 793.31 was the most abundant O-glycan structure in SLG saliva commonly detected in both mice. Lectin staining of salivary gland tissue showed that SLG stained strongly with Maackia amurensis lectin II (MAL II) while Sambucus nigra agglutinin (SNA) stained little, if any, SLG. The messenger RNA expression of St3gal1 that encodes an α-2,3 sialic acid sialyltransferase SIAT4-A showed a decrease in SLG of aged mice, confirmed by a Western blot analysis. Lectin blot analysis in SLG saliva revealed that the relative signal intensity detected by MAL II was significantly lower in aged SLG. Our results suggest that spinnbarkeit decreases in SLG of aging mice due to downregulation of sialic acid linked to α-2,3 sialic acid sialyltransferase expression.
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Affiliation(s)
- M Yamada
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - C Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - Y Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - R Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
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8
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Endoplasmic reticulum stress affects mouse salivary protein secretion induced by chronic administration of an α 1-adrenergic agonist. Histochem Cell Biol 2022; 157:443-457. [PMID: 35037129 DOI: 10.1007/s00418-021-02047-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2021] [Indexed: 11/04/2022]
Abstract
Stress stimulates both the sympathetic-adrenomedullary and hypothalamus-pituitary-adrenal axes. Activation of these axes results in the release of catecholamines, which in turn affects salivary secretion. Thus, repetitive stimulation of the α1-adrenergic receptor could be useful for studying the effects of chronic stress on the salivary gland. Salivary protein concentration and kallikrein activity were significantly lower in mice following chronic phenylephrine (PHE) administration. Chronic PHE administration led to significantly increased expression of the 78-kDa glucose-regulated protein, activating transcription factor 4, and activating transcription factor 6. Histological analyses revealed a decrease in the size of the serous cell and apical cytoplasm. These results suggest that repetitive pharmacological stimulation of the sympathetic nervous system elicits ER stress and translational suppression. In addition, PHE-treated mice exhibited a decrease in intracellular Ca2+ influx elicited by carbachol, a muscarine receptor agonist in the submandibular gland. The present findings suggest that chronic psychological, social, and physical stress could adversely affect Ca2+ regulation.
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Peña-Münzenmayer G, Kondo Y, Salinas C, Sarmiento J, Brauchi S, Catalán MA. Activation of the Ae4 (Slc4a9) cation-driven Cl -/HCO 3- exchanger by the cAMP-dependent protein kinase in salivary gland acinar cells. Am J Physiol Gastrointest Liver Physiol 2021; 321:G628-G638. [PMID: 34585968 PMCID: PMC8887885 DOI: 10.1152/ajpgi.00145.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 01/31/2023]
Abstract
Ae4 transporters are critical for Cl- uptake across the basolateral membrane of acinar cells in the submandibular gland (SMG). Although required for fluid secretion, little is known about the physiological regulation of Ae4. To investigate whether Ae4 is regulated by the cAMP-dependent signaling pathway, we measured Cl-/HCO3- exchanger activity in SMG acinar cells from Ae2-/- mice, which only express Ae4, and found that the Ae4-mediated activity was increased in response to β-adrenergic receptor stimulation. Moreover, pretreatment with H89, an inhibitor of the cAMP-activated kinase (PKA), prevented the stimulation of Ae4 exchangers. We then expressed Ae4 in CHO-K1 cells and found that the Ae4-mediated activity was increased when Ae4 is coexpressed with the catalytic subunit of PKA (PKAc), which is constitutively active. Ae4 sequence analysis showed two potential PKA phosphorylation serine residues located at the intracellular NH2-terminal domain according to a homology model of Ae4. NH2-terminal domain Ser residues were mutated to alanine (S173A and S273A, respectively), where the Cl-/HCO3- exchanger activity displayed by the mutant S173A was not activated by PKA. Conversely, S273A mutant kept the PKA dependency. Together, we conclude that Ae4 is stimulated by PKA in SMG acinar cells by a mechanism that probably depends on the phosphorylation of S173.NEW & NOTEWORTHY We found that Ae4 exchanger activity in secretory salivary gland acinar cells is increased upon β-adrenergic receptor stimulation. The activation of Ae4 was prevented by H89, a nonselective PKA inhibitor. Protein sequence analysis revealed two residues (S173 and S273) that are potential targets of cAMP-dependent protein kinase (PKA). Experiments in CHO-K1 cells expressing S173A and S273A mutants showed that S173A, but not S273A, is not activated by PKA.
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Affiliation(s)
- Gaspar Peña-Münzenmayer
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Constanza Salinas
- Facultad de Medicina, Instituto de Fisiología, Universidad Austral de Chile, Valdivia, Chile
| | - José Sarmiento
- Facultad de Medicina, Instituto de Fisiología, Universidad Austral de Chile, Valdivia, Chile
| | - Sebastián Brauchi
- Facultad de Medicina, Instituto de Fisiología, Universidad Austral de Chile, Valdivia, Chile
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Valdivia, Chile
| | - Marcelo A Catalán
- Facultad de Ciencias de la Salud, Universidad Arturo Prat, Iquique, Chile
- Facultad de Medicina, Instituto de Fisiología, Universidad Austral de Chile, Valdivia, Chile
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10
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The cAMP-phosphodiesterase 4 (PDE4) controls β-adrenoceptor- and CFTR-dependent saliva secretion in mice. Biochem J 2021; 478:1891-1906. [PMID: 33944911 DOI: 10.1042/bcj20210212] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/22/2021] [Accepted: 05/04/2021] [Indexed: 12/22/2022]
Abstract
Saliva, while often taken for granted, is indispensable for oral health and overall well-being, as inferred from the significant impairments suffered by patients with salivary gland dysfunction. Here, we show that treatment with several structurally distinct PAN-PDE4 inhibitors, but not a PDE3 inhibitor, induces saliva secretion in mice, indicating it is a class-effect of PDE4 inhibitors. In anesthetized mice, while neuronal regulations are suppressed, PDE4 inhibition potentiates a β-adrenoceptor-induced salivation, that is ablated by the β-blocker Propranolol and is absent from homozygous ΔF508-CFTR mice lacking functional CFTR. These data suggest that PDE4 acts within salivary glands to gate saliva secretion that is contingent upon the cAMP/PKA-dependent activation of CFTR. Indeed, PDE4 contributes the majority of total cAMP-hydrolytic capacity in submandibular-, sublingual-, and parotid glands, the three major salivary glands of the mouse. In awake mice, PDE4 inhibitor-induced salivation is reduced by CFTR deficiency or β-blockers, but also by the muscarinic blocker Atropine, suggesting an additional, central/neuronal mechanism of PDE4 inhibitor action. The PDE4 family comprises four subtypes, PDE4A-D. Ablation of PDE4D, but not PDE4A-C, produced a minor effect on saliva secretion, implying that while PDE4D may play a predominant role, PDE4 inhibitor-induced salivation results from the concurrent inactivation of multiple (at least two) PDE4 subtypes. Taken together, our data reveal a critical role for PDE4/PDE4D in controlling CFTR function in an in vivo model and in inducing salivation, hinting at a therapeutic potential of PDE4 inhibition for cystic fibrosis and conditions associated with xerostomia.
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11
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Culp DJ, Zhang Z, Evans RL. VIP and muscarinic synergistic mucin secretion by salivary mucous cells is mediated by enhanced PKC activity via VIP-induced release of an intracellular Ca 2+ pool. Pflugers Arch 2020; 472:385-403. [PMID: 31932898 DOI: 10.1007/s00424-020-02348-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/09/2019] [Accepted: 01/06/2020] [Indexed: 12/12/2022]
Abstract
Mucin secretion by salivary mucous glands is mediated predominantly by parasympathetic acetylcholine activation of cholinergic muscarinic receptors via increased intracellular free calcium ([Ca2+]i) and activation of conventional protein kinase C isozymes (cPKC). However, the parasympathetic co-neurotransmitter, vasoactive intestinal peptide (VIP), also initiates secretion, but to a lesser extent. In the present study, cross talk between VIP- and muscarinic-induced mucin secretion was investigated using isolated rat sublingual tubuloacini. VIP-induced secretion is mediated by cAMP-activated protein kinase A (PKA), independently of increased [Ca2+]i. Synergistic secretion between VIP and the muscarinic agonist, carbachol, was demonstrated but only with submaximal carbachol. Carbachol has no effect on cAMP ± VIP. Instead, PKA activated by VIP releases Ca2+ from an intracellular pool maintained by the sarco/endoplasmic reticulum Ca2+-ATPase pump. Calcium release was independent of phospholipase C activity. The resultant sustained [Ca2+]i increase is additive to submaximal, but not maximal carbachol-induced [Ca2+]i. Synergistic mucin secretion was mimicked by VIP plus either phorbol 12-myristate 13-acetate or 0.01 μM thapsigargin, and blocked by the PKC inhibitor, Gö6976. VIP-induced Ca2+ release also promoted store-operated Ca2+ entry. Synergism is therefore driven by VIP-mediated [Ca2+]i augmenting cPKC activity to enhance muscarinic mucin secretion. Additional data suggest ryanodine receptors control VIP/PKA-mediated Ca2+ release from a Ca2+ pool also responsive to maximal carbachol. A working model of muscarinic and VIP control of mucous cell exocrine secretion is presented. Results are discussed in relation to synergistic mechanisms in other secretory cells, and the physiological and therapeutic significance of VIP/muscarinic synergism controlling salivary mucous cell exocrine secretion.
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Affiliation(s)
- David J Culp
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA. .,Department of Oral Biology, UF College of Dentistry, P.O. Box 100424, Gainesville, FL, 32610-3003, USA.
| | - Z Zhang
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA
| | - R L Evans
- Center for Oral Biology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY, 14642, USA.,Unilever Research & Development, Port Sunlight Laboratory, Quarry Road East, Bebington, Wirral, CH63 3JW, UK
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