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Muñoz Forti K, Weisman GA, Jasmer KJ. Cell type-specific transforming growth factor-β (TGF-β) signaling in the regulation of salivary gland fibrosis and regeneration. J Oral Biol Craniofac Res 2024; 14:257-272. [PMID: 38559587 PMCID: PMC10979288 DOI: 10.1016/j.jobcr.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 01/13/2024] [Accepted: 03/09/2024] [Indexed: 04/04/2024] Open
Abstract
Salivary gland damage and hypofunction result from various disorders, including autoimmune Sjögren's disease (SjD) and IgG4-related disease (IgG4-RD), as well as a side effect of radiotherapy for treating head and neck cancers. There are no therapeutic strategies to prevent the loss of salivary gland function in these disorders nor facilitate functional salivary gland regeneration. However, ongoing aquaporin-1 gene therapy trials to restore saliva flow show promise. To identify and develop novel therapeutic targets, we must better understand the cell-specific signaling processes involved in salivary gland regeneration. Transforming growth factor-β (TGF-β) signaling is essential to tissue fibrosis, a major endpoint in salivary gland degeneration, which develops in the salivary glands of patients with SjD, IgG4-RD, and radiation-induced damage. Though the deposition and remodeling of extracellular matrix proteins are essential to repair salivary gland damage, pathological fibrosis results in tissue hardening and chronic salivary gland dysfunction orchestrated by multiple cell types, including fibroblasts, myofibroblasts, endothelial cells, stromal cells, and lymphocytes, macrophages, and other immune cell populations. This review is focused on the role of TGF-β signaling in the development of salivary gland fibrosis and the potential for targeting TGF-β as a novel therapeutic approach to regenerate functional salivary glands. The studies presented highlight the divergent roles of TGF-β signaling in salivary gland development and dysfunction and illuminate specific cell populations in damaged or diseased salivary glands that mediate the effects of TGF-β. Overall, these studies strongly support the premise that blocking TGF-β signaling holds promise for the regeneration of functional salivary glands.
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Affiliation(s)
- Kevin Muñoz Forti
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
| | - Gary A. Weisman
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
| | - Kimberly J. Jasmer
- Christopher S. Bond Life Sciences Center and Department of Biochemistry, University of Missouri, United States
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Yokoyama M, Katsumata-Kato O, Fujita-Yoshigaki J. Acinar Cell Proliferation Promoted by BMP2 in Injured Mouse Parotid Gland: BMP2 Promotes Cell Proliferation in Parotid Gland. Int J Dent 2023; 2023:1765317. [PMID: 37033127 PMCID: PMC10081898 DOI: 10.1155/2023/1765317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 04/03/2023] Open
Abstract
Objective. To identify factors that affect salivary gland recovery, we investigated the expression and function of bone morphogenetic protein 2 (BMP2) in mice. Materials and Methods. Using a micro clip, mice parotid glands were removed 7 days after the ligation of the unilateral parotid excretory duct. Thereafter, they were weighed and stained with hematoxylin and eosin, and BMP2 expression was examined via real-time reverse transcription-polymerase chain reaction. Primary cultures of parotid glands were prepared, and BMP2 protein was added to the culture medium for 48 hr to examine its effect on cell proliferation. E-cadherin and vimentin expression was examined using western blotting. Finally, immunohistochemical staining using an anti-Ki67 antibody was performed. Results. Duct-ligated parotid glands weighed less than those that were collected after sham surgery and showed acinar cell atrophy. They also showed higher BMP2 expression than control glands. Primary-cultured parotid acinar cells supplemented with BMP2 showed higher proliferative potential than control cells. Furthermore, they showed E-cadherin, but not vimentin, expression, and their percentage of Ki67-positive cells were higher than that corresponding to the controls. Conclusions. Injury to salivary glands by excretory duct ligation increased BMP2 expression, which may be involved in maintaining salivary gland function by inducing acinar cell proliferation.
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Affiliation(s)
- Megumi Yokoyama
- Department of Physiology, Nihon University School of Dentistry at Matsudo, Chiba, Japan
| | - Osamu Katsumata-Kato
- Department of Physiology, Nihon University School of Dentistry at Matsudo, Chiba, Japan
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The Role of mTOR and Injury in Developing Salispheres. Biomedicines 2023; 11:biomedicines11020604. [PMID: 36831139 PMCID: PMC9953188 DOI: 10.3390/biomedicines11020604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
Salispheres are the representative primitive cells of salivary glands grown in vitro in a nonadherent system. In this study, we used the ligation model for salisphere isolation after seven days of obstruction of the main excretory duct of the submandibular gland. The mammalian target of rapamycin (mTOR) is a critical signalling pathway involved in many cellular functions and is suggested to play a role in atrophy. We determined the role of mTOR and injury in the formation and development of salispheres. Morphological assessments and Western blot analysis illustrated how mTOR inhibition by rapamycin impaired the assembly of salispheres and how indirect stimulation of mTOR by lithium chloride (LiCl) assisted in the expansion of the salispheres. The use of rapamycin highlighted the necessity of mTOR for the development of salispheres as it affected the morphology and inhibited the phosphorylation of the eukaryotic translation initiation factor 4E-binding protein (4e-bp1). mTOR activity also appeared to be a crucial regulator for growing salispheres, even from the ligated gland. However, atrophy induced by ductal ligation resulted in a morphological alteration. The phosphorylation of 4e-bp1 and S6 ribosomal protein in cultured salispheres from ligated glands suggests that mTOR was not responsible for the morphological modification, but other unexplored factors were involved. This exploratory study indicates that active mTOR is essential for growing healthy salispheres. In addition, mTOR stimulation by LiCl could effectively play a role in the expansion of salispheres. The impact of atrophy on salispheres suggests a complex mechanism behind the morphological alteration, which requires further investigation.
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Uchida H, Ingalls MH, Maruyama EO, Johnston CJ, Hernady E, Faustoferri RC, Ovitt CE. Short-term and bystander effects of radiation on murine submandibular glands. Dis Model Mech 2022; 15:dmm049570. [PMID: 36263624 PMCID: PMC9683099 DOI: 10.1242/dmm.049570] [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: 03/21/2022] [Accepted: 10/13/2022] [Indexed: 11/20/2022] Open
Abstract
Many patients treated for head and neck cancers experience salivary gland hypofunction due to radiation damage. Understanding the mechanisms of cellular damage induced by radiation treatment is important in order to design methods of radioprotection. In addition, it is crucial to recognize the indirect effects of irradiation and the systemic responses that may alter saliva secretion. In this study, radiation was delivered to murine submandibular glands (SMGs) bilaterally, using a 137Cs gamma ray irradiator, or unilaterally, using a small-animal radiation research platform (SARRP). Analysis at 3, 24 and 48 h showed dynamic changes in mRNA and protein expression in SMGs irradiated bilaterally. Unilateral irradiation using the SARRP caused similar changes in the irradiated SMGs, as well as significant off-target, bystander effects in the non-irradiated contralateral SMGs.
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Affiliation(s)
- Hitoshi Uchida
- Center for Oral Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Matthew H. Ingalls
- Center for Oral Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Eri O. Maruyama
- Center for Oral Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Carl J. Johnston
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Eric Hernady
- Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Roberta C. Faustoferri
- Center for Oral Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Catherine E. Ovitt
- Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY 14642USA
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Maternal Fluoride Exposure Exerts Different Toxicity Patterns in Parotid and Submandibular Glands of Offspring Rats. Int J Mol Sci 2022; 23:ijms23137217. [PMID: 35806221 PMCID: PMC9266858 DOI: 10.3390/ijms23137217] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 06/09/2022] [Accepted: 06/13/2022] [Indexed: 12/19/2022] Open
Abstract
There is currently a controversial and heated debate about the safety and ethical aspects of fluoride (F) used for human consumption. Thus, this study assessed the effects of prenatal and postnatal F exposure of rats on the salivary glands of their offspring. Pregnant rats were exposed to 0, 10, or 50 mg F/L from the drinking water, from the first day of gestation until offspring weaning (42 days). The offspring rats were euthanized for the collection of the parotid (PA) and submandibular (SM) glands, to assess the oxidative biochemistry and to perform morphometric and immunohistochemical analyses. F exposure was associated with a decrease in the antioxidant competence of PA in the 10 mg F/L group, contrasting with the increase observed in the 50 mg F/L group. On the other hand, the antioxidant competence of the SM glands was decreased at both concentrations. Moreover, both 10 and 50 mg F/L groups showed lower anti-α-smooth muscle actin immunostaining area in SM, while exposure to 50 mg F/L was associated with changes in gland morphometry by increasing the duct area in both glands. These findings demonstrate a greater susceptibility of the SM glands of the offspring to F at high concentration in comparison to PA, reinforcing the need to adhere to the optimum F levels recommended by the regulatory agencies. Such findings must be interpreted with caution, especially considering their translational meaning.
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Responses of salivary glands to intake of soft diet. J Oral Biosci 2022; 64:210-216. [DOI: 10.1016/j.job.2022.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 11/20/2022]
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He X, Wang S, Sun H, He H, Shi Y, Wu Y, Wu H, Liu Z, Zhuang J, Li W. Lacrimal Gland Microenvironment Changes After Obstruction of Lacrimal Gland Ducts. Invest Ophthalmol Vis Sci 2022; 63:14. [PMID: 35289845 PMCID: PMC8934564 DOI: 10.1167/iovs.63.3.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Purpose To investigate microenvironment changes of the lacrimal gland after obstruction of lacrimal gland ducts. Methods The ducts of rat exorbital lacrimal gland were ligated by sutures for different durations. After that, the sutures in some animals were released, and they were observed for 21 days to evaluate the recovery of the lacrimal gland. Slit lamp and tear secretion test was performed to evaluate ocular surface and lacrimal gland function. The lacrimal gland and cornea were harvested and processed for hematoxylin and eosin staining, oil red O staining, LipidTOX staining, Masson staining, quantitative real time polymerase chain reaction, and immunofluorescence staining. Results After the lacrimal gland ducts were blocked, tear secretion and the weight of the lacrimal gland were reduced. Incidence of corneal neovascularization increased after seven days. Intraglandular ducts dilated and acini destroyed. Long-term ligation induced fibrosis and lipid accumulation of the lacrimal glands. Inflammatory cell infiltrated and inflammatory factors upregulated. Proliferative and apoptotic cells increased. Structure of myoepithelial cells and basement membrane was destroyed. The p63 expression increased whereas Pax6 expression decreased. After suture release, tear secretion and structure of acini could recover in less than seven days after ligation, with a decrease in inflammatory cell infiltration and fibrosis relief. Apoptotic cells and proliferative cells increased at five days thereafter. The structure of the myoepithelial cells and basement membrane could not recover three days after ligation, and the number of mesenchymal cells increased in ligation after five to 14 days. Conclusions Blockage of the lacrimal gland ducts results in dystrophy of lacrimal gland acini cells, inflammation, and lipid accumulation of the lacrimal gland microenvironment. Long-term duct blockage will cause irreversible lacrimal gland failure.
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Affiliation(s)
- Xin He
- Department of Ophthalmology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Shaopan Wang
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China.,Institute of Artificial Intelligence, Xiamen University, Xiamen, Fujian, China
| | - Huimin Sun
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Hui He
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Yalin Shi
- Department of Ophthalmology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yiming Wu
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Han Wu
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Zuguo Liu
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
| | - Jingyi Zhuang
- Department of Ophthalmology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Wei Li
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China.,Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Xiamen, Fujian, China
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8
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Experimental Animal Model Systems for Understanding Salivary Secretory Disorders. Int J Mol Sci 2020; 21:ijms21228423. [PMID: 33182571 PMCID: PMC7696548 DOI: 10.3390/ijms21228423] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022] Open
Abstract
Salivary secretory disorders are life-disrupting pathologic conditions with a high prevalence, especially in the geriatric population. Both patients and clinicians frequently feel helpless and get frustrated by the currently available therapeutic strategies, which consist mainly of palliative managements. Accordingly, to unravel the underlying mechanisms and to develop effective and curative strategies, several animal models have been developed and introduced. Experimental findings from these models have contributed to answer biological and biomedical questions. This review aims to provide various methodological considerations used for the examination of pathological fundamentals in salivary disorders using animal models and to summarize the obtained findings. The information provided in this review could provide plausible solutions for overcoming salivary disorders and also suggest purpose-specific experimental animal systems.
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Ninche N, Kwak M, Ghazizadeh S. Diverse epithelial cell populations contribute to the regeneration of secretory units in injured salivary glands. Development 2020; 147:dev.192807. [PMID: 32994165 DOI: 10.1242/dev.192807] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/11/2020] [Indexed: 12/15/2022]
Abstract
Salivary glands exert exocrine secretory function to provide saliva for lubrication and protection of the oral cavity. Its epithelium consists of several differentiated cell types, including acinar, ductal and myoepithelial cells, that are maintained in a lineage-restricted manner during homeostasis or after mild injuries. Glandular regeneration following a near complete loss of secretory cells, however, may involve cellular plasticity, although the mechanism and extent of such plasticity remain unclear. Here, by combining lineage-tracing experiments with a model of severe glandular injury in the mouse submandibular gland, we show that de novo formation of acini involves induction of cellular plasticity in multiple non-acinar cell populations. Fate-mapping analysis revealed that, although ductal stem cells marked by cytokeratin K14 and Axin2 undergo a multipotency switch, they do not make a significant contribution to acinar regeneration. Intriguingly, more than 80% of regenerated acini derive from differentiated cells, including myoepithelial and ductal cells, that appear to dedifferentiate to a progenitor-like state before re-differentiation into acinar cells. The potential of diverse cell populations serving as a reserve source for acini widens the therapeutic options for hyposalivation.
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Affiliation(s)
- Ninche Ninche
- Department of Oral Biology and Pathology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Mingyu Kwak
- Department of Oral Biology and Pathology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Soosan Ghazizadeh
- Department of Oral Biology and Pathology, Stony Brook University, Stony Brook, NY 11794, USA
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D’Agostino C, Elkashty OA, Chivasso C, Perret J, Tran SD, Delporte C. Insight into Salivary Gland Aquaporins. Cells 2020; 9:cells9061547. [PMID: 32630469 PMCID: PMC7349754 DOI: 10.3390/cells9061547] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 06/23/2020] [Accepted: 06/23/2020] [Indexed: 12/18/2022] Open
Abstract
The main role of salivary glands (SG) is the production and secretion of saliva, in which aquaporins (AQPs) play a key role by ensuring water flow. The AQPs are transmembrane channel proteins permeable to water to allow water transport across cell membranes according to osmotic gradient. This review gives an insight into SG AQPs. Indeed, it gives a summary of the expression and localization of AQPs in adult human, rat and mouse SG, as well as of their physiological role in SG function. Furthermore, the review provides a comprehensive view of the involvement of AQPs in pathological conditions affecting SG, including Sjögren's syndrome, diabetes, agedness, head and neck cancer radiotherapy and SG cancer. These conditions are characterized by salivary hypofunction resulting in xerostomia. A specific focus is given on current and future therapeutic strategies aiming at AQPs to treat xerostomia. A deeper understanding of the AQPs involvement in molecular mechanisms of saliva secretion and diseases offered new avenues for therapeutic approaches, including drugs, gene therapy and tissue engineering. As such, AQP5 represents a potential therapeutic target in different strategies for the treatment of xerostomia.
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Affiliation(s)
- Claudia D’Agostino
- Laboratory of Pathophysiological and Nutritional Biochemistry, Faculty of Medicine, Université Libre de Bruxelles, 808 Route de Lennik, Blg G/E CP 611, B-1070 Brussels, Belgium; (C.D.); (C.C.); (J.P.)
| | - Osama A. Elkashty
- McGill Craniofacial Tissue Engineering and Stem Cells Laboratory, Faculty of Dentistry, McGill University, Montreal, QC H3A 0C7, Canada; (O.A.E.); (S.D.T.)
- Oral Pathology Department, Faculty of Dentistry, Mansoura University, 35516 Mansoura, Egypt
| | - Clara Chivasso
- Laboratory of Pathophysiological and Nutritional Biochemistry, Faculty of Medicine, Université Libre de Bruxelles, 808 Route de Lennik, Blg G/E CP 611, B-1070 Brussels, Belgium; (C.D.); (C.C.); (J.P.)
| | - Jason Perret
- Laboratory of Pathophysiological and Nutritional Biochemistry, Faculty of Medicine, Université Libre de Bruxelles, 808 Route de Lennik, Blg G/E CP 611, B-1070 Brussels, Belgium; (C.D.); (C.C.); (J.P.)
| | - Simon D. Tran
- McGill Craniofacial Tissue Engineering and Stem Cells Laboratory, Faculty of Dentistry, McGill University, Montreal, QC H3A 0C7, Canada; (O.A.E.); (S.D.T.)
| | - Christine Delporte
- Laboratory of Pathophysiological and Nutritional Biochemistry, Faculty of Medicine, Université Libre de Bruxelles, 808 Route de Lennik, Blg G/E CP 611, B-1070 Brussels, Belgium; (C.D.); (C.C.); (J.P.)
- Correspondence: ; Tel.: +32-2-5556210
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Hosoi K, Yao C, Hasegawa T, Yoshimura H, Akamatsu T. Dynamics of Salivary Gland AQP5 under Normal and Pathologic Conditions. Int J Mol Sci 2020; 21:ijms21041182. [PMID: 32053992 PMCID: PMC7072788 DOI: 10.3390/ijms21041182] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 12/13/2022] Open
Abstract
AQP5 plays an important role in the salivary gland function. The mRNA and protein for aquaporin 5 (AQP5) are expressed in the acini from embryonic days E13-16 and E17-18, respectively and for entire postnatal days. Ligation-reopening of main excretory duct induces changes in the AQP5 level which would give an insight for mechanism of regeneration/self-duplication of acinar cells. The AQP5 level in the submandibular gland (SMG) decreases by chorda tympani denervation (CTD) via activation autophagosome, suggesting that its level in the SMG under normal condition is maintained by parasympathetic nerve. Isoproterenol (IPR), a β-adrenergic agonist, raised the levels of membrane AQP5 protein and its mRNA in the parotid gland (PG), suggesting coupling of the AQP5 dynamic and amylase secretion-restoration cycle. In the PG, lipopolysaccharide (LPS) is shown to activate mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signalings and potentially downregulate AQP5 expression via cross coupling of activator protein-1 (AP-1) and NF-κB. In most species, Ser-156 and Thr-259 of AQP5 are experimentally phosphorylated, which is enhanced by cAMP analogues and forskolin. cAMP-dependent phosphorylation of AQP5 does not seem to be markedly involved in regulation of its intracellular trafficking but seems to play a role in its constitutive expression and lateral diffusion in the cell membrane. Additionally, Ser-156 phosphorylation may be important for cancer development.
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Affiliation(s)
- Kazuo Hosoi
- Department of Molecular Oral Physiology, Division of Oral Science, Graduate School of Biomedical Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8504, Japan; (C.Y.); (T.H.); (T.A.)
- Kosei Pharmaceutical Co., Ltd., Osaka-shi, Osaka 540–0039, Japan
- Correspondence: (K.H.); (H.Y.)
| | - Chenjuan Yao
- Department of Molecular Oral Physiology, Division of Oral Science, Graduate School of Biomedical Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8504, Japan; (C.Y.); (T.H.); (T.A.)
| | - Takahiro Hasegawa
- Department of Molecular Oral Physiology, Division of Oral Science, Graduate School of Biomedical Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8504, Japan; (C.Y.); (T.H.); (T.A.)
| | - Hiroshi Yoshimura
- Department of Molecular Oral Physiology, Division of Oral Science, Graduate School of Biomedical Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8504, Japan; (C.Y.); (T.H.); (T.A.)
- Correspondence: (K.H.); (H.Y.)
| | - Tetsuya Akamatsu
- Department of Molecular Oral Physiology, Division of Oral Science, Graduate School of Biomedical Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8504, Japan; (C.Y.); (T.H.); (T.A.)
- Field of Biomolecular Functions and Technology, Division of Bioscience and Bioindustry, Graduate School of Technology, Industrial and Social Sciences, Tokushima University, Tokushima-shi, Tokushima 770-8513, Japan
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12
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Koutlas IG, Dolan M, Lingen MW, Argyris PP. Plasmacytoid cells in salivary pleomorphic adenoma: an alternative interpretation of their immunohistochemical characteristics highlights function and capability for epithelial-mesenchymal transition. Oral Surg Oral Med Oral Pathol Oral Radiol 2019; 128:515-529. [PMID: 31400990 DOI: 10.1016/j.oooo.2019.01.081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 01/02/2019] [Accepted: 01/29/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Plasmacytoid cells (PLCs) in salivary pleomorphic adenoma (SPA) are regarded as modified neoplastic myoepithelia and define plasmacytoid myoepithelioma (pMYO). However, histochemically, immunohistochemically and ultrastructurally, PLCs fail to demonstrate frank myogenous properties. Epithelial-mesenchymal transition (EMT) may explain the phenotypes in SPA. Our aim was to evaluate (1) PLCs with accepted or purported myoepithelial and EMT-related markers; and (2) pMYOs for PLAG1 aberrations by using fluorescence in situ hybridization. STUDY DESIGN Eight SPAs with or without PLC-predominance and 3 pMYOs were immunohistochemically studied. RESULTS PLCs in SPA and pMYO exhibited strong, scattered to diffuse positivity for K7, rare K14 positivity and were mostly negative for α-smooth muscle actin, h-caldesmon, and p63/p40. S100 staining was strong and diffuse, whereas calponin was variable. DOG1 was negative. PLCs in pMYO and PLC-rich SPA exhibited selective or diffuse WT1 and D2-40 immunoreactivity. EMT markers SNAIL/SLUG exhibited strong and variable immunoreactivity in PLCs in contrast to weak or absent E-cadherin expression. SOX10 was diffusely and strongly positive. PLAG1 rearrangement was present in 1 pMYO. CONCLUSIONS PLCs mostly fail to express myoepithelial markers; PLCs are neoplastic cells adapting to microenvironmental changes and capable of EMT; and tumors composed solely of PLCs are apparently SPAs depleted of a ductal component.
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Affiliation(s)
- Ioannis G Koutlas
- Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, MN, USA.
| | - Michelle Dolan
- Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, University of Minnesota, Minneapolis, MN, USA
| | - Mark W Lingen
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Prokopios P Argyris
- Division of Oral and Maxillofacial Pathology, School of Dentistry, University of Minnesota, Minneapolis, MN, USA; Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN, USA
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Triantafyllou A, Mikkelsen LH, Gnepp DR, Andreasen S, Hunt JL, Devaney KO, Vander Poorten V, Rinaldo A, Willems SM, Ferlito A. Salivary myoepithelial cells: an addendum. Ultrastruct Pathol 2018; 42:465-476. [DOI: 10.1080/01913123.2018.1551259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Asterios Triantafyllou
- Department of Pathology, Liverpool Clinical Laboratories, Royal Liverpool University Hospital, Liverpool, UK
- School of Dentistry, University of Liverpool, Liverpool, UK
| | - Lauge Hjorth Mikkelsen
- Department of Pathology, Eye Pathology Section, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Ophthalmology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Douglas R. Gnepp
- Department of Pathology, Providence, Rhode Island, and Fall River, MA, USA
| | - Simon Andreasen
- Department of Pathology and Department of Otolaryngology Head and Neck Surgery and Audiology, Rigshospitalet, Copenhagen
| | - Jennifer L. Hunt
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | | | - Vincent Vander Poorten
- Otorhinolaryngology-Head and Neck Surgery and Department of Oncology-Section Head and Neck Oncology, University Hospitals Leuven, Leuven, Belgium
- European Salivary Gland Society, Geneva, Switzerland
| | | | - Stefan M. Willems
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alfio Ferlito
- Coordinator of the International Head and Neck Scientific Group, Padua, Italy
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14
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Li W, Wei L, Wang F, Peng S, Cheng Y, Li B. An experimental chronic obstructive sialadenitis model by partial ligation of the submandibular duct characterised by sialography, histology, and transmission electron microscopy. J Oral Rehabil 2018; 45:983-989. [PMID: 30125980 DOI: 10.1111/joor.12711] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 08/06/2018] [Accepted: 08/15/2018] [Indexed: 01/05/2023]
Abstract
Extensive investigation into the mechanism of chronic obstructive sialadenitis (COS) calls for a reliable model that mimics the onset and progression of the disease. Duct obstruction is closely correlated with COS, and partial duct obstruction is usually observed in COS. Partial ligation of ducts or vessels is a valid treatment to mimic pathological processes in certain animal studies. In this study, we developed a novel animal model of COS by incomplete ligation of Wharton's duct and clarified the corresponding morphological alterations in the submandibular gland. Partial ligation of Wharton's duct in Japanese white rabbits resulted in a gradually progressive COS model as demonstrated by sialographic, gross, microscopic, and ultrastructural changes in acinar and ductal degenerations over 8 weeks. The model is a feasible option for investigating the pathogenesis of COS and evaluating the efficacy and safety of novel treatments of COS.
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Affiliation(s)
- Wei Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China.,Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Lili Wei
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China.,Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Fang Wang
- Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Shangwen Peng
- Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Yong Cheng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China.,Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Bo Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China.,Department of Oral Radiology of School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
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15
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Comparative analysis on the dynamic of lacrimal gland damage and regeneration after Interleukin-1α or duct ligation induced dry eye disease in mice. Exp Eye Res 2018; 172:66-77. [DOI: 10.1016/j.exer.2018.03.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/09/2018] [Accepted: 03/27/2018] [Indexed: 11/15/2022]
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16
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Significance of Interleukin-6/STAT Pathway for the Gene Expression of REG Iα, a New Autoantigen in Sjögren's Syndrome Patients, in Salivary Duct Epithelial Cells. Clin Rev Allergy Immunol 2018; 52:351-363. [PMID: 27339601 DOI: 10.1007/s12016-016-8570-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The regenerating gene, Reg, was originally isolated from a rat regenerating islet complementary DNA (cDNA) library, and its human homologue was named REG Iα. Recently, we reported that REG Iα messenger RNA (mRNA), as well as its product, was overexpressed in ductal epithelial cells in the salivary glands of Sjögren's syndrome patients. Furthermore, autoantibodies against REG Iα were found in the sera of Sjögren's syndrome patients, and the patients who were positive for the anti-REG Iα antibody showed significantly lower saliva secretion than antibody-negative patients. We found the mechanism of REG Iα induction in salivary ductal epithelial cells. Reporter plasmid containing REG Iα promoter (-1190/+26) upstream of a luciferase gene was introduced into human NS-SV-DC and rat A5 salivary ductal cells. The cells were treated with several cytokines (interleukin (IL)-6, IL-8, etc.), upregulated in Sjögren's syndrome salivary ducts, and the transcriptional activity was measured. IL-6 stimulation significantly enhanced the REG Iα promoter activity in both cells. Deletion analysis revealed that the -141∼-117 region of the REG Iα gene was responsible for the promoter activation by IL-6, which contains a consensus sequence for signal transducer and activator of transcription (STAT) binding. The introduction of small interfering RNA for human STAT3 abolished IL-6-induced REG Iα transcription. These results indicated that IL-6 stimulation induced REG Iα transcription through STAT3 activation and binding to the REG Iα promoter in salivary ductal cells. This dependence of REG Iα induction upon IL-6/STAT in salivary duct epithelial cells may play an important role in the pathogenesis/progression of Sjögren's syndrome.
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17
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Lacrimal Gland Repair after Short-term Obstruction of Excretory Duct in Rabbits. Sci Rep 2017; 7:8290. [PMID: 28811503 PMCID: PMC5557958 DOI: 10.1038/s41598-017-08197-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 07/06/2017] [Indexed: 12/13/2022] Open
Abstract
Aqueous tear-deficient dry eye is a multifactorial chronic disorder in which the lacrimal glands fail to produce enough tears to maintain a healthy ocular surface. The existence of lacrimal gland stem/progenitor cells was proposed in several species, yet their origin and characteristics are not very clear. Here, we investigated the presence of resident progenitor cells and their regenerative potential in a rabbit model with lacrimal gland main excretory duct ligation-induced injury. The ligation-injured lacrimal glands temporarily decreased in weight and had impaired tear secretion. Protein expression profiles and transcriptional profiles were obtained from injured tissue. Isolated lacrimal gland progenitor cells were tested and characterized by stem cell-related marker evaluation, single cell clonal assay and three-dimensional (3-D) culture. The results of our study indicate that lacrimal glands are capable of tissue repair after duct ligation-induced injury, likely involving resident stem/progenitor cells and epithelial-mesenchymal transitions. Lacrimal gland progenitor cells isolated from ligated tissue can differentiate in 3-D culture. The results provide further insights into lacrimal gland stem/progenitor cell physiology and their potential for treating severe cases of tear deficiency.
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18
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Murayama K, Kawakami M, Tanaka A. Chronic Changes in the Atrophied Submandibular Gland after Long-term Ligation of the Main Excretory Duct in Mice. J HARD TISSUE BIOL 2017. [DOI: 10.2485/jhtb.26.13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Kazuyoshi Murayama
- Department of Oral and Maxillofacial Surgery, School of Life Dentistry at Niigata, The Nippon Dental University
| | - Miyuki Kawakami
- Department of Oral and Maxillofacial Surgery, School of Life Dentistry at Niigata, The Nippon Dental University
- Division of Cell Regeneration and Transplantation, Advanced Research Center, School of Life Dentistry at Niigata, The Nippon Dental University
| | - Akira Tanaka
- Department of Oral and Maxillofacial Surgery, School of Life Dentistry at Niigata, The Nippon Dental University
- Division of Cell Regeneration and Transplantation, Advanced Research Center, School of Life Dentistry at Niigata, The Nippon Dental University
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19
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Shubin AD, Felong TJ, Graunke D, Ovitt CE, Benoit DS. Development of poly(ethylene glycol) hydrogels for salivary gland tissue engineering applications. Tissue Eng Part A 2015; 21:1733-51. [PMID: 25762214 PMCID: PMC4449707 DOI: 10.1089/ten.tea.2014.0674] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 02/09/2015] [Indexed: 12/21/2022] Open
Abstract
More than 40,000 patients are diagnosed with head and neck cancers annually in the United States with the vast majority receiving radiation therapy. Salivary glands are irreparably damaged by radiation therapy resulting in xerostomia, which severely affects patient quality of life. Cell-based therapies have shown some promise in mouse models of radiation-induced xerostomia, but they suffer from insufficient and inconsistent gland regeneration and accompanying secretory function. To aid in the development of regenerative therapies, poly(ethylene glycol) hydrogels were investigated for the encapsulation of primary submandibular gland (SMG) cells for tissue engineering applications. Different methods of hydrogel formation and cell preparation were examined to identify cytocompatible encapsulation conditions for SMG cells. Cell viability was much higher after thiol-ene polymerizations compared with conventional methacrylate polymerizations due to reduced membrane peroxidation and intracellular reactive oxygen species formation. In addition, the formation of multicellular microspheres before encapsulation maximized cell-cell contacts and increased viability of SMG cells over 14-day culture periods. Thiol-ene hydrogel-encapsulated microspheres also promoted SMG proliferation. Lineage tracing was employed to determine the cellular composition of hydrogel-encapsulated microspheres using markers for acinar (Mist1) and duct (Keratin5) cells. Our findings indicate that both acinar and duct cell phenotypes are present throughout the 14 day culture period. However, the acinar:duct cell ratios are reduced over time, likely due to duct cell proliferation. Altogether, permissive encapsulation methods for primary SMG cells have been identified that promote cell viability, proliferation, and maintenance of differentiated salivary gland cell phenotypes, which allows for translation of this approach for salivary gland tissue engineering applications.
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Affiliation(s)
- Andrew D. Shubin
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Timothy J. Felong
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Dean Graunke
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
| | - Catherine E. Ovitt
- Center for Oral Biology, University of Rochester, Rochester, New York
- Department of Biomedical Genetics, University of Rochester, Rochester, New York
| | - Danielle S.W. Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, New York
- Center for Oral Biology, University of Rochester, Rochester, New York
- Department of Chemical Engineering, University of Rochester, Rochester, New York
- Center for Musculoskeletal Research, Rochester, New York
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20
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Takahashi S, Uekita H, Kato T, Inoue K, Domon T. Growth of rat parotid glands is inhibited by liquid diet feeding. Tissue Cell 2015; 47:336-41. [PMID: 25956847 DOI: 10.1016/j.tice.2015.04.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 03/26/2015] [Accepted: 04/09/2015] [Indexed: 11/26/2022]
Abstract
This study investigated how liquid diet feeding affects the growth of parotid glands. We weaned 21-day-old rats and thereafter fed them a pellet diet (control group) or a liquid diet (experimental group) for 0, 1, 2, 4, or 8 weeks. Their parotid glands were excised, weighed, examined, and tested for 5-bromo-2'-deoxyuridine (BrdU) and cleaved caspase-3 (Casp-3) as markers of proliferation and apoptosis, respectively. Parotid gland weights were consistently smaller in experimental animals than in controls. Morphometrical analysis showed that control group acinar cells increased in area during the experiment, but experimental group acinar cells were almost unchanged. Labeling indices of BrdU in acinar cells in both groups declined during the experiment, but were consistently lower in the experimental group than in controls. Casp-3-positive acinar cells were rare in both groups, which consistently express significantly similar Casp-3 levels. Ultrastructurally, terminal portions of the experimental parotid glands consisted of a few acinar cells that were smaller than those in controls. Control acinar cells showed mitotic figures within short experimental periods, but not in experimental glands. These observations indicate that liquid diet feeding inhibits growth of parotid glands in growing rats through suppression of growth and proliferation of individual acinar cells, but not through apoptosis.
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Affiliation(s)
- Shigeru Takahashi
- Department of Oral Functional Anatomy, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan.
| | - Hiroki Uekita
- Department of Oral Functional Anatomy, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan
| | - Tsuyoshi Kato
- Department of Oral Functional Anatomy, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan
| | - Kiichiro Inoue
- Department of Oral Functional Anatomy, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan
| | - Takanori Domon
- Department of Oral Functional Anatomy, Hokkaido University Graduate School of Dental Medicine, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan
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21
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Guthrie KM, Hardie RJ. Surgical Excision of the Parotid Salivary Gland for Treatment of a Traumatic Mucocele in a Dog. J Am Anim Hosp Assoc 2014; 50:216-20. [DOI: 10.5326/jaaha-ms-6002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A 3 yr old spayed female mixed-breed German shepherd dog was presented with a right facial swelling that developed after fighting with another dog. A parotid salivary mucocele was diagnosed via physical examination, fine-needle aspirate, and sialography of the parotid and mandibular salivary glands. Surgical excision of the right parotid salivary gland and duct was performed along with drainage of the mucocele. Neither intraoperative nor postoperative complications occurred, and follow-up examination 4 mo later revealed no evidence of recurrence. Case outcome was considered excellent. Sialography was useful for confirming the parotid gland as the source of the mucocele. Surgical excision of the parotid salivary gland is technically challenging, but an effective treatment option for traumatic mucoceles in the dog.
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Affiliation(s)
- Kathleen M. Guthrie
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI
| | - Robert J. Hardie
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI
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22
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Immunohistochemical and ultrastructural investigation of acinar cells in submandibular and sublingual glands of rats fed a liquid diet. Tissue Cell 2014; 46:136-43. [DOI: 10.1016/j.tice.2014.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 12/18/2013] [Accepted: 01/16/2014] [Indexed: 11/18/2022]
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23
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Rapamycin delays salivary gland atrophy following ductal ligation. Cell Death Dis 2014; 5:e1146. [PMID: 24675464 PMCID: PMC3973210 DOI: 10.1038/cddis.2014.108] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 01/22/2023]
Abstract
Salivary gland atrophy is a frequent consequence of head and neck cancer irradiation therapy but can potentially be regulated through the mammalian target of rapamycin (mTOR). Excretory duct ligation of the mouse submandibular gland provokes severe glandular atrophy causing activation of mTOR. This study aims to discover the effects of blocking mTOR signaling in ligation-induced atrophic salivary glands. Following 1 week of unilateral submandibular excretory duct ligation: gland weights were significantly reduced, 4E-BP1 and S6rp were activated, and tissue morphology revealed typical signs of atrophy. However, 3 days following ligation with rapamycin treatment, a selective mTOR inhibitor, gland weights were maintained, 4E-BP1 and S6rp phosphorylation was inhibited, and there were morphological signs of recovery from atrophy. However, following 5 and 7 days of ligation and rapamycin treatment, glands expressed active mTOR and showed signs of considerable atrophy. This evidence suggests that inhibition of mTOR by rapamycin delays ligation-induced atrophy of salivary glands.
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24
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Nagai K, Arai H, Okudera M, Yamamura T, Oki H, Komiyama K. Epiregulin is critical for the acinar cell regeneration of the submandibular gland in a mouse duct ligation model. J Oral Pathol Med 2013; 43:378-87. [PMID: 24354788 DOI: 10.1111/jop.12145] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/18/2013] [Indexed: 02/03/2023]
Abstract
Acinar cell regeneration from tubular structures has been reported to occur in duct-deligated salivary glands. However, the detailed process of acinar cell regeneration has not been clarified. We have developed a mouse duct ligation model to clarify the mechanisms underlying acinar cell regeneration, and we analyzed the epidermal growth factor receptor (EGFR) and epidermal growth factor (EGF) ligands using the model. We studied these ligands expressions in the course of acinar cell regeneration using immunohistochemistry and RT-PCR methods. In the duct-ligated portion of the submandibular gland (SMG) that underwent atrophy, newly formed acinar cells were observed arising from the tubular structures after the release of the duct obstruction. The constitutive expression of EGFR was observed by immunohistochemistry in both the duct-ligated and duct-deligated animals as well as in normal controls. The EGFR phosphorylation detected on the tubular structures after duct ligation paralleled the acinar cell regeneration. RT-PCR showed an increase in the epiregulin and heparin-binding EGF levels from day 0 to day 3 after the release of the duct obstruction. The EGF level was increased only after day 7. In vitro, cultured cells isolated from ligated SMGs proliferated and produced EGF ligands following the addition of epiregulin to the culture medium. These findings suggest that the tubular structures localized in an atrophic gland are the source of acinar cell regeneration of the salivary gland. The induction of EGF ligands, in particular epiregulin, may play an important role in acinar cell regeneration in this model.
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Affiliation(s)
- Koichi Nagai
- Department of Pathology, Nihon University School of Dentistry, Tokyo, Japan
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25
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Maria OM, Maria SM, Redman RS, Maria AM, Saad El-Din TA, Soussa EF, Tran SD. Effects of double ligation of Stensen's duct on the rabbit parotid gland. Biotech Histochem 2013; 89:181-98. [PMID: 24053197 DOI: 10.3109/10520295.2013.832798] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14-30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts pre-ligation to surrounding a majority of the residual duct-like structures, many of which clearly were atrophic acini. Thus, both atrophy and apoptosis made major contributions to the post-ligation reduction in gland size. Structures also occurred with both ductal and acinar markers that suggested acini differentiating into ducts. Overall, the reaction to duct ligation proceeded at a considerably slower pace in the rabbit parotid glands than has been reported for the salivary glands of the rat.
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Affiliation(s)
- O M Maria
- Faculty of Dentistry, McGill University , Montreal , Canada
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26
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A perspective of comparative salivary and breast pathology. Part I: microstructural aspects, adaptations and cellular events. Eur Arch Otorhinolaryngol 2013; 271:647-63. [PMID: 23649507 DOI: 10.1007/s00405-013-2488-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 04/08/2013] [Indexed: 10/26/2022]
Abstract
This is the first part of a review comparing the pathology of salivary and mammary glands. Here, less obvious similarities and differences in functional histology and their influences on pathology are examined with emphasis on myoepithelial cells, stromal components, analogues of mucosa-associated lymphoid tissue, steroid receptors, and intraparenchymal cells of monocytic lineage. Particular cell phenotypes (oncocytic, apocrine, neuroendocrine and clear) are critically evaluated and responses to atrophy, infarction and fine-needle aspiration biopsy procedures are highlighted together with aspects of metaplasia, regeneration, ageing and microcalcification. Areas of controversy or uncertainty which may benefit from further investigations are also discussed.
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27
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Involvement of apoptosis and proliferation of acinar cells in atrophy of rat parotid glands induced by liquid diet. J Mol Histol 2012; 43:761-6. [PMID: 22918835 DOI: 10.1007/s10735-012-9442-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 08/13/2012] [Indexed: 10/28/2022]
Abstract
Parotid glands of experimental animals fed a liquid diet are reported to show atrophy (Hall and Schneyer 1964; Wilborn and Schneyer 1970; Hand and Ho 1981; Scott et al. 1990; Scott and Gunn 1991). To clarify whether apoptosis and proliferation of acinar cells participate in atrophy of rat parotid glands induced by liquid diet, rats were fed a liquid diet and compared to pellet-fed controls. Parotid glands were removed at 3, 7, 14 or 21 days, weighed, and examined using transmission electron microscopy (TEM), and studied immunohistochemically for cleaved-caspase-3 (Casp-3), a marker of apoptotic cells, and 5-bromo-2'-deoxyuridine (BrdU), a marker for proliferating cells. Body weights of experimental rats fed liquid diets were not significantly different from controls fed pellet diets; however weights of experimental parotid glands were smaller than those of controls. In the experimental parotid glands, structures like apoptotic bodies were histologically observed in acini at each time point; more Casp-3-positive acinar cells were identified in experimental parotid glands than in the controls on days 3, 7, and 14. Experimental glands showed fewer BrdU-positive acinar cells at each time point. TEM confirmed typical apoptotic acinar cells in the atrophic glands. These findings suggest that increased acinar cell apoptosis and reduced acinar cell proliferation occur in atrophic parotid glands of rats fed a liquid diet.
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28
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Purwanti N, Karabasil MR, Matsuo S, Chen G, Javkhlan P, Azlina A, Hasegawa T, Yao C, Akamatsu T, Hosoi K. Induction of Sca-1 via activation of STAT3 system in the duct cells of the mouse submandibular gland by ligation of the main excretory duct. Am J Physiol Gastrointest Liver Physiol 2011; 301:G814-24. [PMID: 21868636 DOI: 10.1152/ajpgi.00408.2010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
To examine the very initial step that takes place immediately after tissue injury and is linked to tissue regeneration, we employed the submandibular gland (SMG), which was injured by ligation of its main excretory duct (MED). Ligation of the MED of the SMG in mice induced the expression of Sca-1, a protein marker of hematopoietic stem cells. In the normal gland, a low level of Sca-1 was expressed, which was localized predominantly in the excretory duct cells. At 1 day after ligation, Sca-1 expression increased prominently in almost all of cells in the duct system, but not in the acinar cells. The level of Sca-1 mRNA had begun to increase at 6 h after ligation and continuously rose thereafter until it reached a plateau, which occurred ∼12 h after ligation. STAT3 phosphorylated at its tyrosine-705 (p-STAT3) in the ligated gland increased immediately after ligation, and it was localized in the nuclei of all duct cells. The results of an EMSA revealed the specific binding of a nuclear extract to the sequence of the γ-interferon activation site (GAS) present in the Sca-1 promoter and confirmed that such binding increased after ligation. Thus the present study suggests that STAT3, having been phosphorylated following MED ligation, was transferred to the nucleus, where it bound to the GAS element in the promoter of Sca-1 gene, resulting in promotion of Sca-1 gene expression. Actual prevention of STAT3 phosphorylation reduced the ligation-induced Sca-1 elevation.
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Affiliation(s)
- Nunuk Purwanti
- Department of Molecular Oral Physiology, Institute of Health Biosciences, The University of Tokushima Graduate School, Kuramoto-cho, Tokushima-shi, Japan
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29
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Ascl3 knockout and cell ablation models reveal complexity of salivary gland maintenance and regeneration. Dev Biol 2011; 353:186-93. [PMID: 21377457 DOI: 10.1016/j.ydbio.2011.02.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 12/01/2010] [Accepted: 02/08/2011] [Indexed: 12/22/2022]
Abstract
Expression of the transcription factor, Ascl3, marks a population of adult progenitor cells, which can give rise to both acinar and duct cell types in the murine salivary glands. Using a previously reported Ascl3(EGFP-Cre/+) knock-in strain, we demonstrate that Ascl3-expressing cells represent a molecularly distinct, and proliferating population of progenitor cells located in salivary gland ducts. To investigate both the role of the Ascl3 transcription factor, and the role of the cells in which it is expressed, we generated knockout and cell-specific ablation models. Ascl3 knockout mice develop smaller salivary glands than wild type littermates, but secrete saliva normally. They display a lower level of cell proliferation, consistent with their smaller size. In the absence of Ascl3, the cells maintain their progenitor function and continue to generate both acinar and duct cells. To directly test the role of the progenitor cells, themselves, in salivary gland development and regeneration, we used Cre-activated expression of diphtheria toxin (DTA) in the Ascl3-expressing (Ascl3+) cell population, resulting in specific cell ablation of Ascl3+ cells. In the absence of the Ascl3+ progenitor cells, the mice developed morphologically normal, albeit smaller, salivary glands able to secrete saliva. Furthermore, in a ductal ligation model of salivary gland injury, the glands of these mice were able to regenerate acinar cells. Our results indicate that Ascl3+ cells are active proliferating progenitors, but they are not the only precursors for salivary gland development or regeneration. We conclude that maintenance of tissue homeostasis in the salivary gland must involve more than one progenitor cell population.
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30
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Purwanti N, Tsuji D, Azlina A, Karabasil MR, Javkhlan P, Hasegawa T, Yao C, Akamatsu T, Itoh K, Hosoi K. Induction of Sca-1 in the duct cells of the mouse submandibular gland by obstruction of the main excretory duct. J Oral Pathol Med 2011; 40:651-8. [PMID: 21884259 DOI: 10.1111/j.1600-0714.2011.01011.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The effect of ligation of the main excretory duct (MED) of the mouse submandibular gland (SMG) on the expression of Sca-1, a stem cell antigen, was examined by Western blotting and immunohistochemistry. By Western blotting, the expression of Sca-1 with a molecular weight of 18 kDa was identified in the normal gland. At 1 day post-ligation, the expression level of Sca-1 was strongly increased in the experimental gland and weakly in the contralateral gland, and such expression in both glands decreased at 6 days. By immunohistochemistry, Sca-1 was detected weakly in the apical membrane of excretory duct (ED) cells of the SMG under the normal condition. By duct ligation, Sca-1 became expressed strongly in most cells of the two major duct systems, i.e., the striated duct (SD) and granular convoluted tubules (GCT), but was not detected in the acinar (Ac) cells. By fluorescence-activated cell sorter (FACS) analysis, the number of side population (SP) cells in this gland was found to be increased by ligation. These results imply that Sca-1-positive cells may have a role in the duct cell proliferation in the regeneration step elicited by MED ligation-induced injury.
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Affiliation(s)
- Nunuk Purwanti
- Department of Molecular Oral Physiology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima-shi, Tokushima, Japan
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Redman RS, Ball WD, Mezey E, Key S. Dispersed donor salivary gland cells are widely distributed in the recipient gland when infused up the ductal tree. Biotech Histochem 2010; 84:253-60. [PMID: 19572222 DOI: 10.3109/10520290903081377] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The salivary glands often are severely and permanently damaged by therapeutic irradiation for cancer of the head and neck. The markedly reduced quantity and quality of saliva results in greatly increased susceptibility to dental caries and infection of the oral mucosa and alveolar bone. Recently, subcapsular injection of cultured mouse salivary gland cells has achieved a significant degree of regeneration in a previously irradiated mouse salivary gland; however, the recovery was limited to one lobule. We describe here a method for delivering donor rat salivary gland cells via the main duct that distributes several thousand cells throughout the recipient rat's salivary gland. The donated cells exhibited the cytodifferentiation of the structures in which they lodged, i.e., acini, granular convoluted tubules, and the several types of ducts. This method may facilitate the simultaneous functional recovery of almost all of the lobules of irradiated rat salivary glands.
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Affiliation(s)
- R S Redman
- Oral Pathology Research Laboratory (151-I), Department of Veterans Affairs Medical Center, 50 Irving Street NW, Washington, DC 20422, USA.
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Purwanti N, Azlina A, Karabasil MR, Hasegawa T, Yao C, Akamatsu T, Hosoi K. Involvement of the IL-6/STAT3/Sca-1 system in proliferation of duct cells following duct ligation in the submandibular gland of mice. THE JOURNAL OF MEDICAL INVESTIGATION 2010; 56 Suppl:253-4. [PMID: 20224192 DOI: 10.2152/jmi.56.253] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Ligation of the main excretory duct (MED) of the mouse submandibular gland (SMG) induced the expression of Sca-1, a stem cell marker. Sca-1 expression increased prominently in almost all of cells in the duct system, except the acinar cells. Sca-1 induction was accompanied with phosphorylated-STAT3 (Y705) elevation, which was localized in the nuclei of all duct cells. Electrophoretic mobility shift assay (EMSA) confirmed the specific binding of STAT3 to the GAS sequence, a biding site of gamma interferon activating site. Present study suggested one of the initial steps of the tissue regeneration after injury includes STAT3 pathway.
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Affiliation(s)
- Nunuk Purwanti
- Department of Molecular Oral Physiology, Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan
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Cotroneo E, Proctor GB, Carpenter GH. Regeneration of acinar cells following ligation of rat submandibular gland retraces the embryonic-perinatal pathway of cytodifferentiation. Differentiation 2010; 79:120-30. [PMID: 20056310 PMCID: PMC2841285 DOI: 10.1016/j.diff.2009.11.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2009] [Revised: 11/20/2009] [Accepted: 11/29/2009] [Indexed: 11/19/2022]
Abstract
Rat submandibular gland can regenerate following ligation-induced atrophy, eventually recovering its normal morphology and function. Previous studies have suggested that the regeneration process implies both self-proliferation of existing acini and formation of new acinar cells. One hypothesis is that new acinar cells may differentiate from the ductal cells in a similar fashion to the process of cytodifferentiation occurring during submandibular glandular development. In this study atrophy was induced, under recovery anaesthesia, by applying a metal clip on the main duct of the submandibular gland without including the chorda lingual nerve. After 2 weeks the duct was deligated for 3, 5 or 7 days or 8 weeks and the glands collected. Tissue was prepared for immunohistochemistry, biochemical analysis and RNA extraction. The histology of the regenerated glands shows several normal-looking acini, which have regained their glycoprotein content (AB/PAS positive), data also confirmed by biochemical analysis (SDS-PAGE/PAS). Regenerating tissue was characterized by the presence of embryonic-like branched structures ending with AB/PAS positive acinar cells. The proteins SMG-B and PSP are normally expressed in acinar cell precursors during development but only by intercalated ductal cells in the adult stage. In the adult regenerating gland mRNA levels of both SMG-B and PSP were found to be up-regulated compared to ligated glands and SMG-B expression localized to acinar cells whilst the ductal cells were negative. This study of rat submandibular gland regeneration suggests new acinar cells have differentiated from ducts and express markers of acinar cell precursors in a similar manner to the cytodifferentiation process occurring during glandular development.
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Affiliation(s)
| | | | - Guy H. Carpenter
- Salivary Research Unit, floor 17 Tower Wing, King's College London Dental Institute, London,UK, SE1 9RT
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Redman RS. On approaches to the functional restoration of salivary glands damaged by radiation therapy for head and neck cancer, with a review of related aspects of salivary gland morphology and development. Biotech Histochem 2009; 83:103-30. [PMID: 18828044 DOI: 10.1080/10520290802374683] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Radiation therapy for cancer of the head and neck can devastate the salivary glands and partially devitalize the mandible and maxilla. As a result, saliva production is drastically reduced and its quality adversely altered. Without diligent home and professional care, the teeth are subject to rapid destruction by caries, necessitating extractions with attendant high risk of necrosis of the supporting bone. Innovative techniques in delivery of radiation therapy and administration of drugs that selectively protect normal tissues can reduce significantly the radiation effects on salivary glands. Nonetheless, many patients still suffer severe oral dryness. I review here the functional morphology and development of salivary glands as these relate to approaches to preventing and restoring radiation-induced loss of salivary function. The acinar cells are responsible for most of the fluid and organic material in saliva, while the larger ducts influence the inorganic content. A central theme of this review is the extent to which the several types of epithelial cells in salivary glands may be pluripotential and the circumstances that may influence their ability to replace cells that have been lost or functionally inactivated due to the effects of radiation. The evidence suggests that the highly differentiated cells of the acini and large ducts of mature glands can replace themselves except when the respective pools of available cells are greatly diminished via apoptosis or necrosis owing to severely stressful events. Under the latter circumstances, relatively undifferentiated cells in the intercalated ducts proliferate and redifferentiate as may be required to replenish the depleted pools. It is likely that some, if not many, acinar cells may de-differentiate into intercalated duct-like cells and thus add to the pool of progenitor cells in such situations. If the stress is heavy doses of radiation, however, the result is not only the death of acinar cells, but also a marked decline in functional differentiation and proliferative capacity of all of the surviving cells, including those with progenitor capability. Restoration of gland function, therefore, seems to require increasing the secretory capacity of the surviving cells, or replacing the acinar cells and their progenitors either in the existing gland remnants or with artificial glands.
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Affiliation(s)
- R S Redman
- Oral Pathology Research Laboratory, Department of Veterans Affairs Medical Center, Washington, DC, USA.
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Zoellner H, Bielek E, Vanyek E, Fabry A, Wojta J, Hofler M, Binder BR. Canalicular Fragmentation of Apoptotic Human Endothelial Cells. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10623329609024694] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Takahashi S, Yoshimura Y, Yamamoto T, Wakita M. Cellular expression of Bcl-2 and Bax in atrophic submandibular glands of rats. Int J Exp Pathol 2008; 89:303-8. [PMID: 18808524 DOI: 10.1111/j.1365-2613.2008.00613.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In submandibular gland atrophy, most acinar cells disappear by apoptosis, while many duct cells remain. The present study aimed to establish whether Bcl-2 and Bax, members of the Bcl-2 gene family, regulating the signalling pathway of apoptosis were involved in duct cell survival and acinar cell death in atrophic submandibular glands. The excretory duct of rat submandibular gland was doubly ligated with metal clips from 1 to 14 days to induce atrophy to the gland. The expressions of Bcl-2 and Bax in the atrophic submandibular gland were examined using immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). Immunohistochemically, Bcl-2 expression was identified in duct cells in the experimental glands at all time points. Some acinar cells showed Bax positivity 1 day after excretory duct ligation, and there were more Bax-positive acinar cells on days 3 and 5 when many apoptotic acinar cells were observed. Analysis by RT-PCR showed that the expression of mRNA for Bcl-2 became stronger as the glandular atrophy progressed and that Bax mRNA strongly expressed on days 1 and 3. These observations suggest that Bcl-2 inhibits duct cell apoptosis and Bax promotes apoptosis of acinar cells during atrophy of submandibular glands.
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Affiliation(s)
- Shigeru Takahashi
- Department of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan.
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Miyazaki T, Tatsukawa S, Kitamura H, Ina K, Abe H, Fujikura Y. Morphological and functional changes of the rat parotid glandular cells by clipping and reopening the parotid duct, using HAM8 antibody. Anat Sci Int 2008; 83:89-95. [PMID: 18507618 DOI: 10.1111/j.1447-073x.2007.00211.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose of this experiment is to examine the proliferative process of rat acinar cells after parotid duct ligation and reopening. Two experimental groups were observed. The first group was killed from 0 to 14 days after the duct ligation. In the second group, the duct was clipped for 14 days, and it was reopened. Following a period of from 2 to 28 days after removal of the clip, the glands were removed to perform a histological analysis, including hematoxylin-eosin (HE), immunofluorescent staining using HAM8 antibody, which recognizes connexin 32, and transmission electron microscopy (TEM). In the experimental gland from the 1st group at 6 days after ligation (I-6D), the acinar cells disappeared. In the tissue from the 2nd group 8 days after reopening (II-8D), newly formed acinar cells were found again. Lobular structure of the parotid glands recovered in the II-21D. HAM8 signals were observed between normal acinar cells, while they declined in the tissue from I-1D, and they were not observed in the I-2D. HAM8 signals were first observed in the II-25D and then subsequently returned to normal levels in the II-28D. These results suggest that the intercellular communication and functional recovery was not complete 25 days after reopening of the duct.In conclusion, the recovery of the acinar structure was recognized during an extended period of duct ligation, however, a time lag between the morphological and functional recovery was found to exist.
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Affiliation(s)
- Takashi Miyazaki
- Department of Anatomy, Biology and Medicine, Oita University, 1-1 Idaigaoka, Hasama-machi, Yufu City, Oita, Japan
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Kim YJ, Kwon HJ, Shinozaki N, Hashimoto S, Shimono M, Cho SW, Jung HS. Comparative analysis of ABCG2-expressing and label-retaining cells in mouse submandibular gland. Cell Tissue Res 2008; 334:47-53. [PMID: 18688650 DOI: 10.1007/s00441-008-0667-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 06/24/2008] [Indexed: 11/30/2022]
Abstract
The submandibular gland (SMG) is a tissue that can be regenerated in a tissue injury model and that has adult stem cells capable of self-renewal and differentiation into functional cells. We have analyzed the localization of label-retaining cells (LRCs), which are putative progenitor cells, by using the BrdU-labeling method. 5-Bromo-2'-deoxyuridine (BrdU) injection followed by a long chasing period permitted the identification of LRCs based on the slow-cycling characteristic. In order to confirm the accurate localization of LRCs, BrdU and SMG-specific markers, including aquaporin5, cytokeratin, and smooth muscle actin, were examined by double-immunofluorescence staining. We found that LRCs were distributed in the acinus, duct, myoepithelium, and connective tissue. Moreover, ABCG2 (a known stem cell marker) was used for the characterization of LRCs and the localization of cells as putative stem/progenitor cells. ABCG2-expressing cells were distributed in various regions of the SMG but did not co-localize with LRCs. We suggest that putative progenitor cells exist in various regions of the SMG and have diverse capacities to differentiate into specific cells.
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Affiliation(s)
- Yeun-Jung Kim
- Department of Oral Biology, Research Center for Orofacial Hard Tissue Regeneration, College of Dentistry, Yonsei University, Seodaemoon-Gu, Seoul, 120-752, Korea
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Cotroneo E, Proctor GB, Paterson KL, Carpenter GH. Early markers of regeneration following ductal ligation in rat submandibular gland. Cell Tissue Res 2008; 332:227-35. [PMID: 18335244 PMCID: PMC2493059 DOI: 10.1007/s00441-008-0588-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 01/21/2008] [Indexed: 11/26/2022]
Abstract
Rat submandibular glands can recover their function and secretory protein content following ductal ligation-induced atrophy. Morphological studies have established that following ligation, deligation of the gland allows the regeneration of new salivary gland tissue. However, little is known about changes happening during early regeneration following intra-oral duct ligation, which does not damage the parasympathetic nerves. Glands that had been 2 weeks ligated or 2 weeks ligated + 3 days deligated were compared. Tissue was prepared for histological, immunohistochemical (SMG-B and Ki-67) and immunocytochemical analyses (smooth muscle actin, aquaporin 5). Haematoxylin and eosin staining of deligated glands showed that some acini regained their cytoplasmic volume; moreover, the loss of Alcian blue/periodic acid-Schiff's staining from the lumen of ducts suggested successful deligation. The deligated gland was characterized by atypical acinar-ductal branched structures, which were less frequent in the ligated gland and rarely seen in normal unoperated tissue. Myoepithelial cells were also investigated since changes in their morphology reflected changes in the acini morphology not readily detected by conventional staining. Actin staining revealed the presence of some shrunken acini in the atrophic tissue, whereas they had regained their normal morphology in the deligated gland suggesting that the acini were recovering. Some acini during deligation regained aquaporin 5 expression, which had decreased during atrophy. SMG-B protein, located in the pro-acinar cell during gland development and usually found in the intercalated duct cells in the adult, was detected in the newly formed acini of the deligated gland. This study suggests that morphological markers of regeneration appear as early as 3 days following ligation removal.
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Affiliation(s)
- Emanuele Cotroneo
- Salivary Research Unit, King's College London, Floor 17, Guy's Tower, Dental Institute at Guy's, King's College and St Thomas' Hospital, London SE1 9RT, UK.
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Correia PN, Carpenter GH, Osailan SM, Paterson KL, Proctor GB. Acute salivary gland hypofunction in the duct ligation model in the absence of inflammation. Oral Dis 2008; 14:520-8. [PMID: 18221457 PMCID: PMC2592348 DOI: 10.1111/j.1601-0825.2007.01413.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Objective The commonly associated aetiology of salivary gland inflammation and salivary hypofunction has led to the widely held belief that inflammation causes salivary gland hypofunction. Indeed, our own recent study seemed to support this contention. Here, we tested the hypothesis that, in an acute duct ligation model, eliminating inflammation the submandibular gland would recover normal function. Materials and methods Ligation of the rat submandibular gland excretory duct for 24 h was used to induce inflammation and salivary gland hypofunction. A group of duct ligated rats was compared with a second group given dexamethasone, on the day of duct ligation. Twenty-four hours later salivary gland function was assessed and salivary glands were collected. Results Histology and myeloperoxidase activity assay revealed a profound decrease in inflammatory cell infiltration of ligated glands from rats given dexamethasone, compared with ligated glands in the absence of dexamethasone. Salivary flow rate evoked by methacholine was decreased (P < 0.01) by approximately 56% (ligated vs control, 79 ± 9 μl min−1 g−1vs 177 ± 11 μl min−1 g−1) and salivary flow from ligated dexamethasone-treated and ligated glands was similar. Conclusion Despite eliminating the inflammatory reaction in the ligated gland, salivary hypofunction was not reversed, suggesting that other mechanisms must be at work in the ligation-induced salivary hypofunction.
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Affiliation(s)
- P N Correia
- Salivary Research Unit, King's College London Dental Institute at Guy's, King's College and St Thomas' Hospitals, London, UK.
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Bolitho C, Xu W, Zoellner H. Negative Feedback for Endothelial Apoptosis: A Potential Physiological Role for Fibroblast Growth Factor. J Vasc Res 2007; 45:193-204. [DOI: 10.1159/000111072] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Accepted: 08/14/2007] [Indexed: 11/19/2022] Open
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Matsumoto S, Okumura K, Ogata A, Hisatomi Y, Sato A, Hattori K, Matsumoto M, Kaji Y, Takahashi M, Yamamoto T, Nakamura K, Endo F. Isolation of tissue progenitor cells from duct-ligated salivary glands of swine. CLONING AND STEM CELLS 2007; 9:176-90. [PMID: 17579551 DOI: 10.1089/clo.2006.0022] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Tissue stem cells participate in the repopulation of tissue after injury. Tissue injury stimulates the normally quiescent tissue stem cells to differentiate and proliferate, in the process of replacing and/or repairing the damaged cells, and hence effecting tissue regeneration. The salivary glands retain the ability for frequent regeneration. Previously, we isolated progenitor cells from the injured salivary glands of mice and rats that differentiated into hepatic and pancreatic lineages. The isolated progenitors were CD49f-positive and intracellular laminin-positive, and proliferated on type I collagen while maintaining their multipotency. In this study, we analyzed the tissue stem cells induced by ligating the main excretory duct of the salivary gland in swine. After duct ligation of the gland, acinar cells receded due to apoptosis, and epithelial cells subsequently proliferated. We cultured cells obtained from the duct-ligated salivary gland and purified the cells by limited dilution. The isolated cells were positive for CD29, CD49f, intracellular laminin, AFP, CK19, CK18, and Thy-1(CD90), and weakly positive for c-Kit (CD117). After three-dimensional formation, the cells expressed insulin and albumin. We designated the cells as swine salivary gland-derived progenitor cells. Gene expression of insulin and albumin was significantly increased (five-fold) and that of insulin was also increased (3.8-fold) with differentiation medium with nicotinamide and/or GLP-1 treatment in spherical culture. The expressions of albumin and insulin were 1/10-fold and 1/4-fold compared to porcine hepatocytes and pancreatic endocrine cells. The differentiated SGP cells could release insulin, which were stimulated by glucose and potassium. These results indicate that swine SGP cells could differentiate into hepatocytes and beta-cells, functionally. Swine SGP cells were useful tools for therapy and analyzing endodermal regenerative models in large animals.
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Affiliation(s)
- Shirou Matsumoto
- Department of Pediatrics, Graduate School of Medical Science, Kumamoto University, Kumamoto, Japan
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Takahashi S, Gobe GC, Yoshimura Y, Kohgo T, Yamamoto T, Wakita M. Participation of the Fas and Fas ligand systems in apoptosis during atrophy of the rat submandibular glands. Int J Exp Pathol 2007; 88:9-17. [PMID: 17244334 PMCID: PMC2517292 DOI: 10.1111/j.1365-2613.2006.00511.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Most acinar cells and some duct cells undergo apoptosis during atrophy of the submandibular gland. The present study was designed to elucidate whether Fas and its receptor ligand (FasL) are involved during apoptotic atrophy of the gland. The excretory duct of the right submandibular gland of rats was doubly ligated with metal clips from 1 to 14 days for induction of gland atrophy. Control rats were untreated. Fas and FasL expression in the atrophied submandibular gland was detected using immunohistochemistry (IHC) and Western immunoblot. Expression of activated caspase 8 and activated caspase 3 was also detected with IHC. Fas-positive acinar and duct cells and FasL-positive duct cells increased in the atrophic glands at 3 and 5 days after duct ligation when apoptotic cells were commonly observed. Thereafter, Fas- and FasL-positive cells declined in number. Patterns of expression of Fas and FasL using Western immunoblots concurred with the IHC results. Activated caspase 8-positive cells were present at every time interval but peaked at 3 and 5 days following duct ligation. The cells showing immunoreaction for activated caspase 3 first appeared on day 3, with the peak in apoptosis, after which they decreased. The results indicate that the Fas/FasL systems likely play an important role in apoptotic pathways during atrophy of the submandibular gland.
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Affiliation(s)
- Shigeru Takahashi
- Department of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo, Japan.
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Abstract
Computed tomography was used to evaluate a 7-year-old English bulldog with a history of facial swelling and to aid in the diagnosis of parotid duct sialolithiasis. Removal of the sialolith with repair of the duct was not possible because of ductal fibrosis. Histological evaluation revealed glandular atrophy and fibrosis with lymphoplasmacytic inflammation. The parotid duct was ulcerated and fibrotic, with a mixed inflammatory infiltrate. Surgical excision of the parotid duct and salivary gland was curative.
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Affiliation(s)
- Brian J Trumpatori
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, North Carolina 27606, USA
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Osailan SM, Proctor GB, Carpenter GH, Paterson KL, McGurk M. Recovery of rat submandibular salivary gland function following removal of obstruction: a sialometrical and sialochemical study. Int J Exp Pathol 2006; 87:411-23. [PMID: 17222209 PMCID: PMC2517394 DOI: 10.1111/j.1365-2613.2006.00500.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Accepted: 07/26/2006] [Indexed: 11/30/2022] Open
Abstract
Functional recovery of the rat submandibular gland following ligation of the main excretory duct was examined. Rat submandibular glands were ligated for 1, 4 and 8 weeks using a micro-clip with a plastic tube. Micro-clips were removed and glands were allowed to recover for periods of 8, 16 and 24 weeks. Submandibular glands were stimulated with autonomimetic drugs (methacholine and isoprenaline) and salivas were collected from atrophic or de-ligated and contralateral control glands. Glands recovered almost full size (92% of control gland) following 24 weeks of de-ligation. Saliva volume secreted by ligated/de-ligated (RSM) and control (LSM) glands were similar with different doses of agonists. Protein output expressed per gram of tissue wet weight was similar from both ligated/de-ligated and control glands with all doses of agonist. Sodium and chloride levels were higher from de-ligated glands than contralateral control glands. Protein electrophoresis showed similar profiles of salivary proteins in all samples with some minor differences. Acinar cells in de-ligated glands showed a normal morphology, as indicated by light microscopy, whilst granular ductal cells were fewer and contained fewer secretory granules. Sodium potassium ATPase staining of striated ducts in de-ligated glands was similar to that of control glands. It can be concluded that rat submandibular glands can regenerate following severe atrophy and secrete normal amounts of saliva containing broadly a full profile of secretory proteins. In contrast to acinar cells, ductal cells appear not to recover full function.
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Affiliation(s)
- Samira M Osailan
- Salivary Research Unit, Maxillofacial Surgery, Guy's, King's and St Thomas' Dental Institute, King's College, London, UK.
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Takahashi S, Kohgo T, Nakamura S, Arambawatta AKS, Domon T, Yamamoto T, Wakita M. Biological behavior of myoepithelial cells in the regeneration of rat atrophied sublingual glands following release from duct ligation. J Mol Histol 2005; 36:373-9. [PMID: 16283425 DOI: 10.1007/s10735-005-9009-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Accepted: 09/22/2005] [Indexed: 11/25/2022]
Abstract
The present study aimed to clarify how myoepithelial cells behave during regeneration of an atrophied sublingual gland by investigating cell proliferation and ultrastructure. Atrophy of rat sublingual glands was induced by unilateral ligation of the excretory duct near the hilum with metal clips, which were then removed after one week of ligation for regeneration. The sublingual glands 0-14 days after unligation were examined with single immunohistochemistry for actin as a marker of myoepithelial cells, double immunohistochemistry for actin and proliferating cell nuclear antigen (PCNA) as a marker of proliferating cells, and transmission electron microscopy (TEM). The single immunohistochemistry and TEM showed that myoepithelial cells surrounded residual ducts in the atrophied glands and immature and mature acini in the regenerating glands. Although PCNA-positive myoepithelial cells were identified during regeneration, PCNA labeling indices of myoepithelial cells were low at all time points except at day 7. Ultrastructurally, myoepithelial cells showing bizarre shaped structures in the atrophy changed with maturation of differentiating acinar cells and appeared normal in the regenerated glands. There was no differentiation of the remaining duct cells to myoepithelial cells. These observations suggest that proliferation of myoepithelial cells and differentiation to myoepithelial cells do not commonly participate in the regeneration of atrophied sublingual glands and that the bizarre shaped myoepithelial cells in the atrophied sublingual glands recover the original shapes with acinar cell regeneration.
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Affiliation(s)
- S Takahashi
- Department of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo, 060-8586, Japan,
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Takahashi S, Nakamura S, Domon T, Yamamoto T, Wakita M. Active participation of apoptosis and mitosis in sublingual gland regeneration of the rat following release from duct ligation. J Mol Histol 2005; 36:199-205. [PMID: 15900411 DOI: 10.1007/s10735-005-1764-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Accepted: 08/05/2004] [Indexed: 10/25/2022]
Abstract
This study was designed to establish how mitotic cell proliferation and apoptotic cell death participate in the regeneration of atrophied rat sublingual glands. To induce atrophy to the sublingual gland of rats, the excretory duct was ligated unilaterally near the hilum, and after 1 week of ligation (day 0) the duct ligation was released to enable gland regeneration. The regenerating glands were examined with routine histology, immunohistochemistry for proliferating cell nuclear antigen (PCNA) as a marker of proliferating cells, terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) as a marker of apoptotic cells, and transmission electron microscopy. At day 0, a few acini and many ducts remained in the atrophic sublingual glands, and newly formed immature acini were observed at day 3. Thereafter acinar cells progressively matured and increased in number, although the number of ducts decreased. Many PCNA- and some TUNEL-positive cells were seen in acini and ducts during regeneration. The labeling indices for both cell types were statistically significantly different from that of the control at several time points of the regeneration. Apoptotic and mitotic cells were also confirmed to be present in the experimental sublingual glands by electron microscopy. These observations suggest that apoptosis as well as mitosis of duct and acinar cells actively participate in and play important roles in sublingual gland regeneration.
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Affiliation(s)
- S Takahashi
- Department of Oral Health Science, Hokkaido University Graduate School of Dental Medicine, Sapporo 060-8586, Japan.
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Hisatomi Y, Okumura K, Nakamura K, Matsumoto S, Satoh A, Nagano K, Yamamoto T, Endo F. Flow cytometric isolation of endodermal progenitors from mouse salivary gland differentiate into hepatic and pancreatic lineages. Hepatology 2004; 39:667-75. [PMID: 14999685 DOI: 10.1002/hep.20063] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Experimental injury is useful to induce tissue stem cells, which may exist in small numbers under normal conditions. The salivary glands originate from the endoderm and consist of acinar and ductal epithelial cells, which have exocrine function. After salivary gland duct ligation, acinar cells disappear as a result of apoptosis, and duct epithelium subsequently proliferates. In this study, we analyzed the tissue stem cells induced by salivary gland duct ligation in mice using immunohistochemistry and flow cytometry. We sorted the Sca-1(+)/c-Kit(+) fraction from adult mice salivary glands by way of fluorescence-activated cell sorting. The sorted cells were apparently homogeneous and were designated mouse salivary gland-derived progenitors (mSGPs). mSGP cells differentiated into a hepatic lineage when cultured in matrigel. In spherical culture in the presence of glucagon-like peptide-1 (GLP-1), these cells differentiated into a pancreatic endocrine lineage. When spheroidal bodies of mSGP, 20 to 30 microm in diameter, were transplanted into liver via the portal vein, the cells integrated into hepatic cords and expressed albumin and alpha1-antitrypsin, suggesting that they had differentiated into hepatic-type cells. Moreover, ductlike structures formed by mSGP cells also appeared, epithelial cells of which were positive for cytokeratin 19. In conclusion, fluorescence-activated cell sorting (FACS) based on histologic evidence is efficient in isolating adult tissue stem cells of the salivary gland. Tissue stem cells of endodermal origin (e.g., hepatic oval cells, pancreatic epithelial progenitor cells, and salivary gland progenitor cells) have similarities in their molecular markers and tissue location. Our findings suggest the existence of common tissue stem cells in endoderm-derived organs.
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Affiliation(s)
- Yuichiro Hisatomi
- Department of Pediatrics, Graduate School of Medical Science, Kumamoto University, Honjo 1-1-1, Kumamoto 860-8556, Japan
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Ihrler S, Blasenbreu-Vogt S, Sendelhofert A, Rössle M, Harrison JD, Löhrs U. Regeneration in chronic sialadenitis: an analysis of proliferation and apoptosis based on double immunohistochemical labelling. Virchows Arch 2004; 444:356-61. [PMID: 14762713 DOI: 10.1007/s00428-003-0964-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2003] [Accepted: 12/05/2003] [Indexed: 11/25/2022]
Abstract
The understanding of regeneration in salivary glands as a finely tuned balance of cellular proliferation, differentiation and apoptosis has been limited by the difficulty of identifying proliferating cells. This has been overcome in the present investigation by double immunohistochemical labelling for the proliferation-associated antigen Ki67 and for different cell-type-specific antigens applied to 8 specimens of normal parotids and 16 specimens of chronic parotid sialadenitis with particular reference to acini and intercalated ducts. In comparison with low baseline rates of proliferation in normal parotids, proliferative indices were significantly increased in chronic sialadenitis in mature acinar cells, intercalated ductal cells and myoepithelial cells without evidence of proliferation by an additional population of cells. In accordance with findings in glands of experimental animals, the present data do not support the previously postulated concept of regeneration of acini and intercalated ducts by a hypothetical population of uncommitted ductal stem cells. The demonstration of a profound capacity for intrinsic glandular regeneration from differentiated cells represents a biological basis for the good results obtained from conservative therapy of chronic sialadenitis and offers hope for novel therapies designed to reconstitute impaired salivary flow.
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Affiliation(s)
- Stephan Ihrler
- Institute of Pathology, Ludwig-Maximilians-University, Thalkirchnerstrasse 36, 80337 Munich, Germany.
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