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Singh A, Kaur S, Singh O. Histomorphogenesis of sublingual salivary gland of Indian sheep. J Histotechnol 2024; 47:13-22. [PMID: 37873745 DOI: 10.1080/01478885.2023.2266799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 09/29/2023] [Indexed: 10/25/2023]
Abstract
The primordial anlage of sublingual gland was first noticed as a solid epithelial bud from oral epithelium at the 24th day of foetal development. The terminal buds were arranged in the form of clusters with undifferentiated epithelial cells and terminated in a bulb-like structure in the 30-day-old sheep foetus. On the 37th day, lumenization and branching of the main cord was noticed. The primary septa were observed from the 55th day onwards which resulted in the formation of lobulation on the 60th day. The capsule formation was initiated by aggregation of mesenchymal tissue on the 63rd day. On the 100th day, terminal tubules differentiated to form secretory end pieces. Tubular portions formed intercalated and striated ducts. Predominantly mucous type of acinar cells was seen from the 110th day onwards with myoepithelial cells. The number of lobules increased with increase in parenchyma from 130th day onwards. Micrometrical studies revealed that the mean diameter of acini, intercalated, striated and large ducts was increased with advancement of age and significant differences were observed between groups. Localization of acidic and neutral mucopolysaccharides were observed in mucous and goblet cells. Fine lipid droplets were observed in intralobular and interlobular connective tissue however, phospholipids were observed in cell membrane of acini and ducts. The current investigation provides microstructural standards for the organogenesis of the sublingual gland of miniature sheep and can lay the foundation for further studies in the morphological investigation of salivary gland development.
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Affiliation(s)
- Amandeep Singh
- Department of Veterinary Anatomy, College of Veterinary Sciences, Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), Hisar, India
| | - Simran Kaur
- Department of Animal Genetics and Breeding, College of Veterinary Sciences, Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), Hisar, India
| | - Opinder Singh
- Department of Veterinary Anatomy, College of Veterinary Sciences, Guru Angad Dev Veterinary and Animal Sciences University (GADVASU), Ludhiana, India
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2
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Harada K, Miki K, Tanaka S, Kogo M, Wakisaka S. Lectin histochemistry of posterior lingual glands of developing rats. Sci Rep 2023; 13:10365. [PMID: 37365173 DOI: 10.1038/s41598-023-36154-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 05/30/2023] [Indexed: 06/28/2023] Open
Abstract
The posterior lingual glands are classified as Weber and von Ebner glands. Glycans play an important role in salivary glands. Although the distribution of glycans can explain functional diversity and variation, there are many unknowns in the developing rat posterior lingual glands. The purpose of this study was to elucidate the relationship between the development and function of the posterior lingual gland in rats by histochemical analysis using lectins that bind to sugar residues. In adult rats, Arachis hypogaea (PNA), Glycine maximus (SBA), and Triticum vulgaris (WGA) were associated with serous cells and Dolichos biflorus (DBA) with mucous cells. In both Weber's and von Ebner's glands, all 4 lectins were bound to serous cells in early development, but as development progressed, DBA disappeared in serous cells and only the DBA remained in mucous cells. These results suggest that Galβ (1,3) > Galβ(1,4) > Gal, αGalNAc > αGal > βGalNAc, NeuAc > (GalNAc)2-3>>>GlcNAc, and GalNAcα(1,3) are present in the early stage of development, but that GalNAcα(1,3) disappear in serous cells and only GalNAcα(1,3) are localized in mucous cells after maturation. These results indicate that Weber glands function as serous glands in the early postnatal stage when von Ebner glands have not matured.
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Affiliation(s)
- Kazuma Harada
- The First Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Osaka University, Suita, Japan.
| | - Koji Miki
- Department of Periodonology, Graduate School of Dentistry, Osaka University, Suita, Japan
| | - Susumu Tanaka
- The First Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Osaka University, Suita, Japan
| | - Mikihiko Kogo
- The First Department of Oral and Maxillofacial Surgery, Graduate School of Dentistry, Osaka University, Suita, Japan
| | - Satoshi Wakisaka
- Department of Anatomy and Cell Biology, Graduate School of Dentistry, Osaka University, Suita, Japan
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3
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Singh A, Singh O. Histo-ontogenetic study of the parotid salivary gland of Indian buffalo. Anat Histol Embryol 2020; 50:250-259. [PMID: 33001501 DOI: 10.1111/ahe.12622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/20/2020] [Accepted: 09/07/2020] [Indexed: 11/28/2022]
Abstract
The present study was aimed at elucidating the histogenesis of parotid gland of buffalo. The study was carried out on buffalo foetuses (n = 36), during different stages of prenatal life. The foetuses were categorised into three groups based on their curved crown rump length (CVRL). The primordial anlage of parotid salivary gland was evident at 40th day of development whereas the primary ducts, in the form of cords, were first observed at 81st day of prenatal life. The capsule formation as well as the lobulation of the gland was initiated at 127th day. At 141st day, the duct system of gland was completed. The terminal tubules attained the structure of acini at 167th day. The myoepithelial cells first appeared as flattened basal cells initially around the developing acinar cells at 167th day. The typical compound tubulo-acinar nature of the gland was first observed at 185th day. Purely serous acinar cells were seen from 185th day onwards. The micrometrical studies revealed that the mean diameter of acinar cells, intercalated ducts, striated ducts and large ducts increased with the advancement of age. The serous acinar cells were devoid of acidic as well as neutral mucopolysaccharides in prenatal age groups; however, large ducts with goblet cells exhibited positive reaction. Combined PAS-AB method revealed mixed reaction in acinar cells as well as in large ducts. Fine lipid droplets were observed in intralobular as well as interlobular connective tissue; however, phospholipids were observed in the cell membrane of secretory cells and ducts.
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Affiliation(s)
- Amandeep Singh
- Department of Veterinary Anatomy, Lala Lajpat Rai University of Veterinary and Animal Sciences (LUVAS), Hisar, India
| | - Opinder Singh
- Department of Veterinary Anatomy, Guru Angad Dev Veterinary and Animal Sciences University (GADVASU), Ludhiana, India
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4
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Hakami Z, Hand AR. Expression of aquaporin 5 during murine palatine glands development: a light and electron microscopic immunocytochemical study. Eur J Oral Sci 2020; 128:379-385. [PMID: 32812295 DOI: 10.1111/eos.12734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2020] [Indexed: 11/28/2022]
Abstract
Although aquaporin 5 (AQP5) seems to play a role in cytodifferentiation and cell proliferation during the development of salivary glands, its distribution during minor salivary glands development has been scarcely reported. This study examined the temporal-spatial distribution of AQP5 in the developing rat palatine glands using light and electron microscopy. At embryonic (E) age E18, AQP5 labeling was observed on the cell membranes of some terminal bulb cells. After lumenization at E20, AQP5 labeled the apical membrane in acini where a lumen existed, in addition to displaying positive diffuse cytoplasmic and cell membrane staining. At the electron microscopic level, AQP5 labeled the supranuclear cytoplasm and the luminal microvilli along the apical membrane. At birth, AQP5 was also localized to the lateral membranes associated ultrastructurally with the microvilli of intercellular canaliculi. After postnatal (PN) day PN7, mucous acini and serous demilunes showed reactivity. AQP5 reached peak reactivity around PN13 with a similar staining pattern in all acini, but had reduced dramatically by PN21. Thereafter, AQP5 reactivity was mainly associated with serous cells in adults. In conclusion, the transitory expression of AQP5 during palatine glands development may reflect changing physiological functions of the secretory cells and/or AQP5 throughout the maturation of the glands.
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Affiliation(s)
- Zaki Hakami
- Division of Orthodontics, Department of Preventive Dental Sciences, College of Dentistry, Jazan University, Jazan, Saudi Arabia
| | - Arthur R Hand
- Departments of Craniofacial Sciences and Cell Biology, School of Dental Medicine, UConn Health, Farmington, CT, USA
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5
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Burbelo PD, Ferré EMN, Chaturvedi A, Chiorini JA, Alevizos I, Lionakis MS, Warner BM. Profiling Autoantibodies against Salivary Proteins in Sicca Conditions. J Dent Res 2019; 98:772-778. [PMID: 31095438 DOI: 10.1177/0022034519850564] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Salivary gland dysfunction occurs in several autoimmune and immune-related conditions, including Sjögren syndrome (SS); immune checkpoint inhibitor-induced sicca (ICIS) that develops in some cancer patients and is characterized by severe, sudden-onset dry mouth; and autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). Although subjects with these conditions present with oral dryness and often exhibit inflammatory infiltration of the salivary gland, little is known about the B-cell humoral responses directed against salivary gland protein targets. In this study, autoantibodies were evaluated against Ro52, Ro60, and La, as well as against a panel of 22 proteins derived from the salivary proteome. The tested cohort included healthy volunteers and subjects with SS, ICIS, and APECED without and with sicca. As expected, a high percentage of autoantibody seropositivity was detected against Ro52, Ro60, and La in SS, but only a few ICIS patients were seropositive for these autoantigens. A few APECED subjects also harbored autoantibodies to Ro52 and La, but only Ro60 autoantibodies were weakly associated with a small subset of APECED patients with sicca. Additional testing of the salivary panel failed to detect seropositive autoantibodies against any of the salivary-enriched proteins in the SS and ICIS subjects. However, APECED subjects selectively demonstrated seropositivity against BPI fold containing family A member 1 (BPIFA1), BPI fold containing family A member 2 (BPIFA2)/parotid salivary protein (PSP), and lactoperoxidase, 3 salivary-enriched proteins. Moreover, high levels of serum autoantibodies against BPIFA1 and BPIFA2/PSP occurred in 30% and 67% of the APECED patients with sicca symptoms, respectively, and were associated with an earlier age onset of oral dryness (P = 0.001). These findings highlight the complexity of humoral responses in different sicca diseases and provide new insights and biomarkers for APECED-associated sicca (ClinicalTrials.gov: NCT00001196; NCT00001390; NCT01425892; NCT01386437).
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Affiliation(s)
- P D Burbelo
- 1 Dental Clinical Research Core, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - E M N Ferré
- 2 Fungal Pathogenesis Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - A Chaturvedi
- 1 Dental Clinical Research Core, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - J A Chiorini
- 3 Adeno-Associated Virus Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - I Alevizos
- 4 Sjogren's Clinic, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - M S Lionakis
- 2 Fungal Pathogenesis Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - B M Warner
- 3 Adeno-Associated Virus Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,4 Sjogren's Clinic, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
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Hakami Z, Hand AR. Developmental Morphology of the Palatine Glands in Rats: An Electron Microscope Study. Anat Rec (Hoboken) 2018; 301:1820-1833. [DOI: 10.1002/ar.23927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 03/23/2018] [Accepted: 04/19/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Zaki Hakami
- Department of Preventive Dental Sciences, Division of Orthodontics; College of Dentistry, Jazan University; Jazan Saudi Arabia
| | - Arthur R. Hand
- Department of Craniofacial Sciences and Cell Biology; School of Dental Medicine, University of Connecticut; Farmington Connecticut
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7
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Dagdeviren D, Beallias J, Khan I, Mednieks MI, Hand AR. Response of the mouse sublingual gland to spaceflight. Eur J Oral Sci 2018; 126:373-381. [PMID: 29984852 DOI: 10.1111/eos.12541] [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] [Accepted: 05/16/2018] [Indexed: 01/06/2023]
Abstract
The ultrastructure and immunohistochemistry of secretory proteins of sublingual glands were studied in mice flown on the US space shuttles Discovery [Space Transportation System (STS)-131] and Atlantis (STS-135). No differences in mucous acinar or serous demilune cell structure were observed between sublingual glands of ground (control) and flight mice. In contrast, previous studies showed autophagy and apoptosis of parotid serous acinar cells in flight mice. The expression of parotid secretory protein (PSP) in sublingual demilune cells of STS-131 flight mice was significantly increased compared with ground (control) mice but decreased in STS-135 flight mice. Similarly, expression of mucin (MUC-19) in acinar cells and expression of the type II regulatory subunit of protein kinase A (PKA-RII) in demilune cells were increased in STS-131 flight mice and decreased in STS-135 flight mice, but not significantly. Demilune cell and parotid protein (DCPP) was slightly decreased in mice from both flights, and nuclear PKA-RII was slightly increased. These results indicate that the response of salivary glands to spaceflight conditions varies among the different glands, cell types, and secretory proteins. Additionally, the spaceflight environment, including the effects of microgravity, modifies protein expression. Determining changes in salivary proteins may lead to development of non-invasive methods to assess the physiological status of astronauts.
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Affiliation(s)
- Didem Dagdeviren
- Division of Oral and Maxillofacial Radiology, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - John Beallias
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Izaz Khan
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Maija I Mednieks
- Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - Arthur R Hand
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
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8
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Structural characterization of endogenous peroxidase activity in human, rat, hamster, and Suncus murinus salivary glands. J Oral Biosci 2017. [DOI: 10.1016/j.job.2017.06.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Singh AD, Singh O. Ultrastructural changes in the sublingual salivary gland of prenatal buffalo (Bubalus bubalis). Vet World 2016; 9:326-9. [PMID: 27057120 PMCID: PMC4823297 DOI: 10.14202/vetworld.2016.326-329] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 02/14/2016] [Accepted: 02/20/2016] [Indexed: 11/16/2022] Open
Abstract
Aim: The present study was aimed to elucidate ultrastructural changes in the development of sublingual salivary gland of buffalo during prenatal life. Materials and Methods: The study was carried out on sublingual salivary gland of 36 buffalo fetuses ranging from 13.2 cm curved crown-rump length (CVRL) (88th day) to full term. The fetuses were categorized into three groups based on their CVRL. Results: The cells lining the terminal tubules were undifferentiated with poorly developed cytoplasmic organelles but lacked secretory granules (SGs) at 13.2 cm CVRL (88th day). The SGs appeared first in the form of membrane-bound secretory vesicles with homogeneous electron-dense as well as electron-lucent contents at 21.2 cm CVRL (122nd day); however, mucous acinar cells contained electron-lucent granules, while serous secretory cells as well as serous demilunes showed electron-dense granules at 34 cm CVRL (150th day) of prenatal life. At 53.5 cm CVRL (194th day), both mucous and serous acini were differentiated by the density of SGs. Conclusion: The cytoplasm of acinar cells was filled with mitochondria, rough endoplasmic reticulum, and Golgi profiles in mid and late fetal age groups. The SGs were increased in number during the late fetal age group. The myoepithelial cells (MECs) were located at the base of the acinar cells as well as intercalated and striated ducts and were stellate in shape. The ultrastructure of MEC revealed a parallel stream of myofilaments in the cytoplasm and its processes. The mucous cells were predominantly present in the sublingual salivary gland and were pyramidal in shape.
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Affiliation(s)
- A D Singh
- Department of Veterinary Anatomy, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 141 004, Punjab, India
| | - Opinder Singh
- Department of Veterinary Anatomy, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 141 004, Punjab, India
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10
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Nolte T, Brander-Weber P, Dangler C, Deschl U, Elwell MR, Greaves P, Hailey R, Leach MW, Pandiri AR, Rogers A, Shackelford CC, Spencer A, Tanaka T, Ward JM. Nonproliferative and Proliferative Lesions of the Gastrointestinal Tract, Pancreas and Salivary Glands of the Rat and Mouse. J Toxicol Pathol 2016; 29:1S-125S. [PMID: 26973378 PMCID: PMC4765498 DOI: 10.1293/tox.29.1s] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) project is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature and diagnostic criteria for nonproliferative and proliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature and diagnostic criteria for classifying lesions in the digestive system including the salivary glands and the exocrine pancreas of laboratory rats and mice. Most lesions are illustrated by color photomicrographs. The standardized nomenclature, the diagnostic criteria, and the photomicrographs are also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and age related lesions as well as lesions induced by exposure to test items. Relevant infectious and parasitic lesions are included as well. A widely accepted and utilized international harmonization of nomenclature and diagnostic criteria for the digestive system will decrease misunderstandings among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.
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Affiliation(s)
- Thomas Nolte
- Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an
der Riss, 88397, Germany
- Chairman of the Digestive Tract INHAND Committee
| | - Patricia Brander-Weber
- Novartis Institutes for BioMedical Research, Novartis Pharma
AG, CH-4002 Basel, Switzerland
| | - Charles Dangler
- Jackson Laboratory, Bar Harbor, Maine 04609, USA.
Present: Sanofi5 The Mountain Road, Framingham, Massachusetts 01740,
USA
| | - Ulrich Deschl
- Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an
der Riss, 88397, Germany
| | - Michael R. Elwell
- Covance Laboratories, Inc. 14500 Avion Parkway, Ste 125,
Chantilly, Virginia 20151, USA
| | - Peter Greaves
- University of Leicester, Department of Cancer Studies and
Molecular Medicine, Robert Kilpatrick Clinical Science Building, Leicester Royal
Infirmary, Leicester LE2 7LX, United Kingdom
| | - Richard Hailey
- GlaxoSmithKline PO Box 14164 Durham, North Carolina 27709,
USA
| | | | - Arun R. Pandiri
- Cellular and Molecular Pathology Branch, National Toxicology
Program, National Institute of Environmental Health Sciences, Research Triangle Park,
North Carolina 27709, USA
- Experimental Pathology Laboratories, Inc. PO Box 12766,
Research Triangle Park, North Carolina 27709, USA
| | - Arlin Rogers
- Tufts University, Department of Biomedical Sciences, 274
Tremont Street, Massachusetts 02111, USA
| | - Cynthia C. Shackelford
- Cellular and Molecular Pathology Branch, National Toxicology
Program, National Institute of Environmental Health Sciences, Research Triangle Park,
North Carolina 27709, USA
| | - Andrew Spencer
- Covance Laboratories Ltd, Alnwick Research Centre,
Willowburn Avenue, Alnwick, Northumberland NE66 2JH United Kingdom
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Moriguchi K, Utsumi M, Ohno N. Confocal laser scanning microscopic analysis of ectopic sublingual gland-like tissue inside the hamster submandibular gland. Microsc Res Tech 2013; 76:1284-91. [PMID: 24123513 DOI: 10.1002/jemt.22298] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 09/17/2013] [Accepted: 09/17/2013] [Indexed: 11/07/2022]
Abstract
Based on its histochemical properties, the secretory portion of the hamster submandibular gland has been classified as seromucous cells. The presence of endogenous peroxidase (PO) reaction was shown in the nuclear envelope, cisternae of endoplasmic reticulum and Golgi apparatus. The 3,3'-diaminobenzidene, tetrahydrochloride (DAB) method revealed bipartite secretory granules containing a PO-positive dense core surrounded by a less dense halo in these cells. In the present investigation, serous and mucous-like cells were found in resin-embedded semi-thin sections of the DAB-reacted hamster submandibular gland. These sections were already on glass slides for routine light microscopic observations, therefore electron microscopic analysis could be unrealizable. We then used reflectance-mode confocal laser scanning microscopy to visualize additional sites of PO activity as detected in these sections. Using this approach, we found mucous cells with PO activity-negative secretory granules and seromucous cells with PO activity-positive spot-like secretory granules of the regular sublingual gland most frequently adjacent to the serous cells with typical electron-dense secretory granules. These cells clearly differ from the seromucous cells with bipartite secretory granules and the granular duct cells with typical electron-dense secretory granules of the hamster submandibular gland. Additionally, secretory endpieces of the ectopic sublingual gland-like tissue empty into the duct of the hamster submandibular gland lobule. Thus, our findings suggest that a mass of sublingual gland tissue extends into the hamster submandibular gland during its development, and PO may be synthesized and secreted into the same duct.
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Affiliation(s)
- Keiichi Moriguchi
- Department of Oral Anatomy, School of Dentistry, Aichi-Gakuin University, Nagoya, Aichi, 464-8650, Japan
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12
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Nakamuta N, Nakamuta S, Taniguchi K, Taniguchi K. Analysis of glycoproteins produced by the associated gland in the olfactory organ of lungfish. J Vet Med Sci 2013; 75:887-93. [PMID: 23428778 DOI: 10.1292/jvms.12-0547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The olfactory organ of African lungfish, Protopterus annectens, contains two distinct sensory epithelia: the lamellar olfactory epithelium and the recess epithelium. These epithelia correspond to the olfactory epithelium and the vomeronasal organ of tetrapods, respectively. In contrast to the lamellar olfactory epithelium, which has no associated gland, the recess epithelium is equipped with associated glands. Although the glandular cells and/or the supporting cells are generally presumed to secrete proteins involved in the function of olfactory sensory epithelia, the properties of these proteins in lungfish have not been evaluated to date. In this study, we investigated the associated glands in the olfactory organ of lungfish by transmission electron microscopy and found that the glandular cells contain numerous secretory granules and secrete them from the apical membrane. In addition, we analyzed the olfactory organ by lectin histochemistry using 16 biotinylated lectins. All lectins labeled the secretory granules in the glandular cells with different staining patterns from those of the supporting cells in the lamellar olfactory epithelium or in the recess epithelium. Furthermore, lectin blotting analysis showed that multiple bands were detected by the lectins which specifically labeled the glandular epithelium of the olfactory organ. These results indicate that the secretory products of the associated glands in the recess epithelium have different properties from those of the supporting cells in the olfactory sensory epithelia and contain multiple glycoproteins with different carbohydrate moieties.
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Affiliation(s)
- Nobuaki Nakamuta
- Laboratory of Veterinary Anatomy, Faculty of Agriculture, Iwate University, Morioka, Iwate 020-8550, Japan
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13
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Multiple roles for the actin cytoskeleton during regulated exocytosis. Cell Mol Life Sci 2012; 70:2099-121. [PMID: 22986507 DOI: 10.1007/s00018-012-1156-5] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/28/2012] [Accepted: 08/30/2012] [Indexed: 01/01/2023]
Abstract
Regulated exocytosis is the main mechanism utilized by specialized secretory cells to deliver molecules to the cell surface by virtue of membranous containers (i.e., secretory vesicles). The process involves a series of highly coordinated and sequential steps, which include the biogenesis of the vesicles, their delivery to the cell periphery, their fusion with the plasma membrane, and the release of their content into the extracellular space. Each of these steps is regulated by the actin cytoskeleton. In this review, we summarize the current knowledge regarding the involvement of actin and its associated molecules during each of the exocytic steps in vertebrates, and suggest that the overall role of the actin cytoskeleton during regulated exocytosis is linked to the architecture and the physiology of the secretory cells under examination. Specifically, in neurons, neuroendocrine, endocrine, and hematopoietic cells, which contain small secretory vesicles that undergo rapid exocytosis (on the order of milliseconds), the actin cytoskeleton plays a role in pre-fusion events, where it acts primarily as a functional barrier and facilitates docking. In exocrine and other secretory cells, which contain large secretory vesicles that undergo slow exocytosis (seconds to minutes), the actin cytoskeleton plays a role in post-fusion events, where it regulates the dynamics of the fusion pore, facilitates the integration of the vesicles into the plasma membrane, provides structural support, and promotes the expulsion of large cargo molecules.
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14
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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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Das B, Cash MN, Hand AR, Shivazad A, Culp DJ. Expression of Muc19/Smgc gene products during murine sublingual gland development: cytodifferentiation and maturation of salivary mucous cells. J Histochem Cytochem 2009; 57:383-96. [PMID: 19110483 PMCID: PMC2664977 DOI: 10.1369/jhc.2008.952853] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 12/05/2008] [Indexed: 11/22/2022] Open
Abstract
Muc19/Smgc expresses two splice variants, Smgc (submandibular gland protein C) and Muc19 (mucin 19), the latter a major exocrine product of differentiated murine sublingual mucous cells. Transcripts for Smgc were detected recently in neonatal sublingual glands, suggesting that SMGC proteins are expressed during initial salivary mucous cell cytodifferentiation. We therefore compared developmental expression of transcripts and translation products of Smgc and Muc19 in sublingual glands. We find abundant expression of SMGC within the initial terminal bulbs, with a subsequent decrease as Muc19 expression increases. During postnatal gland expansion, SMGC is found in presumptive newly formed acinar cells and then persists in putative acinar stem cells. Mucin levels increase 7-fold during the first 3 weeks of life, with little change in transcript levels, whereas between postnatal days 21 and 28, there is a 3-fold increase in Muc19 mRNA and heteronuclear RNA. Our collective results demonstrate the direct transition from SMGC to Muc19 expression during early mucous cell cytodifferentiation and further indicate developmentally regulated changes in Muc19/Smgc transcription, alternative splicing, and translation. These changes in Muc19/Smgc gene expression delineate multiple stages of salivary mucous cell cytodifferentiation and subsequent maturation during embryonic gland development through the first 4 weeks of postnatal life.
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Affiliation(s)
- Biswadip Das
- Department of Oral Biology, University of Florida College of Dentistry, 1600 SW Archer Rd., Gainesville, FL 32610-3003, USA
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16
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Bullard T, Koek L, Roztocil E, Kingsley PD, Mirels L, Ovitt CE. Ascl3 expression marks a progenitor population of both acinar and ductal cells in mouse salivary glands. Dev Biol 2008; 320:72-8. [PMID: 18572159 DOI: 10.1016/j.ydbio.2008.04.018] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 02/25/2008] [Accepted: 04/15/2008] [Indexed: 11/30/2022]
Abstract
Ascl3, also know as Sgn1, is a member of the mammalian achaete scute (Mash) gene family of transcription factors, which have been implicated in cell fate specification and differentiation. In the mouse salivary gland, expression of Ascl3 is restricted to a subset of duct cells. Salivary gland function depends on the secretory acinar cells, which are responsible for saliva formation, and duct cells, which modify the saliva and conduct it to the oral cavity. The salivary gland ducts are also the putative site of progenitor cells in the adult gland. Using a Cre recombinase-mediated reporter system, we followed the fate of Ascl3-expressing cells after the introduction of an EGFP-Cre expression cassette into the Ascl3 locus by homologous recombination. Lineage tracing shows that these cells are progenitors of both acinar and ductal cell types in all three major salivary glands. In the differentiated progeny, expression of Ascl3 is down-regulated. These data directly demonstrate a progenitor-progeny relationship between duct cells and the acinar cell compartment, and identify a population of multipotent progenitor cells, marked by expression of Ascl3, which is capable of generating both gland cell types. We conclude that Ascl3-expressing cells contribute to the maintenance of the adult salivary glands.
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Affiliation(s)
- Tara Bullard
- Center for Oral Biology and Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA
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17
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Immunocytochemical analysis of cyclic AMP receptor proteins in the developing rat parotid gland. Arch Oral Biol 2008; 53:429-36. [PMID: 18187105 DOI: 10.1016/j.archoralbio.2007.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 10/23/2007] [Accepted: 11/26/2007] [Indexed: 11/20/2022]
Abstract
UNLABELLED Previous studies showed that regulatory subunits of type II cyclic AMP-dependent protein kinase (RII) are present in adult rat parotid acinar cells, and are secreted into saliva. If the synthesis and intracellular distribution of RII exhibit developmental specificity, then RII can be an indicator of secretory and regulatory activity of salivary glands. OBJECTIVE To determine the expression and distribution of RII in the rat parotid at specific ages representing defined developmental stages. METHODS Parotid glands of fetal, neonatal and adult rats were prepared for morphologic and immunocytochemical study. The cellular distribution of RII was studied using light microscopic immunogold silver staining with anti-RII, and its intracellular distribution using electron microscopic immunogold labeling. RESULTS In utero, parotid RII levels were low; 5-18 days after birth, labeling of secretory granules and cytoplasm rose to a peak, followed by a rapid decrease in both compartments at 25 days. At 60 days, granule labeling increased to levels near those at 18 days, whereas cytoplasmic labeling remained low. Nuclear labeling was highest during the first 3 weeks after birth, and then declined. CONCLUSIONS The higher nuclear and cytoplasmic labeling during the neonatal period may reflect RII involvement in acinar cell differentiation. The accumulation of RII in secretory granules is similar to the pattern of the major salivary proteins, amylase and PSP. The redistribution of RII in these compartments during development may reflect changing gene expression patterns, and may be useful for identification of genetic or metabolic abnormalities.
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Inukai Y, Ikeda R, Aiyama S. Effect of glucocorticoid on the differentiation and development of terminal tubules in the fetal rat submandibular gland. Cells Tissues Organs 2007; 187:233-42. [PMID: 17984628 DOI: 10.1159/000110806] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/16/2007] [Indexed: 11/19/2022] Open
Abstract
Glucocorticoids (CORT) are known to promote branching of the epithelial cords during the development of the rat submandibular gland. The aim of this study was to examine the effect of CORT (triamcinolone) on the differentiation of cells forming the terminal tubules in the developing fetal rat submandibular gland and the properties of the secretory granules. Light and electron microscopy showed that the terminal tubules of the glands in the experimental group contained more type III cells, which have been identified as proacinar cells, than those in the control group, whereas the relative number of type I cells, which have been identified as terminal tubule cells, was reduced. Immunoelectron microscopy using an antibody against neonatal submandibular gland secretory protein B (SMGB) revealed the presence of more gold particles over type III cell granules in the experimental group than in the control group. Lectin histochemistry demonstrated more wheat germ agglutinin (WGA)-labeled gold particles over type III cell granules in the experimental group than in the control group. These findings suggest that CORT promote the differentiation of type III cells, and moreover stimulate the production of secretory granules reactive for SMGB and WGA by acting on the terminal tubules of the developing rat submandibular gland.
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Affiliation(s)
- Yoshio Inukai
- Department of Histology, School of Life Dentistry at Tokyo, Nippon Dental University, Tokyo, Japan
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Jászai J, Janich P, Farkas LM, Fargeas CA, Huttner WB, Corbeil D. Differential expression of Prominin-1 (CD133) and Prominin-2 in major cephalic exocrine glands of adult mice. Histochem Cell Biol 2007; 128:409-19. [PMID: 17874118 DOI: 10.1007/s00418-007-0334-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2007] [Indexed: 01/11/2023]
Abstract
The major cephalic exocrine glands share many morphological and functional features and so can be simultaneously affected in certain autoimmune- and inherited disorders leading to glandular hypofunction. Phenotypic characterization of these exocrine glands is not only an interesting biological issue, but might also be of considerable clinical relevance. The major salivary and lacrimal glands might therefore be potential subjects of future cell-based regenerative/tissue engineering therapeutic approaches. In the present study, we described the expression of the stem and progenitor cell marker Prominin-1 and those of its paralogue, Prominin-2, in the three pairs of major salivary glands, i.e., submandibular-, major sublingual-, and parotid glands in adult mice. We have also documented their expression in the extraorbital lacrimal and meibomian glands (Glandulae tarsales) of the eyelid (Palpebra). Our analysis revealed that murine Prominin-1 and Prominin-2 were differentially expressed in these major cephalic exocrine organs. Expression of Prominin-1 was found to be associated with the duct system, while Prominin-2 expression was mostly, but not exclusively, found in the acinar compartment of these organs with marked differences among the various glands. Finally, we report that Prominin-2, like Prominin-1, is released into the human saliva associated with small membrane particles holding the potential for future diagnostic applications.
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Affiliation(s)
- József Jászai
- Tissue Engineering Laboratories, Biotec, University of Technology Dresden, Tatzberg 47-49, 01307, Dresden, Germany.
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20
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Uehara T. Localization of FGF-6 and FGFR-4 during prenatal and early postnatal development of the mouse sublingual gland. J Oral Sci 2006; 48:9-14. [PMID: 16617195 DOI: 10.2334/josnusd.48.9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
A number of fibroblast growth factors (FGFs) are involved in regulatory mechanisms of the salivary gland development. However, the role of FGF-6 unique in myogenic cells has not been elucidated in the developing sublingual gland. In the present study, temporo-spatial expression of FGF-6 and its receptor (FGFR)-4, in conjunction with some related histo-chemical properties, were investigated in the sublingual gland of the prenatal and early postnatal mice. The earliest expression of both FGF-6 and FGFR-4 was detected in immature acinar cells at gestational day 17 (GD17). The staining intensity increased gradually and some acinar cells showed a distinct staining at postnatal day 0 (PD0). The immunopositive cells had a relatively round profile and were assumed to be acinar cells. The positive staining decreased thereafter and disappeared completely by PD11. To confirm the identity of cells positive for FGF-6, double immunolabeling with anti-alphasmooth muscle actin (alphaSMA) and anti-FGF-6 antibodies was performed. The positive staining of alphaSMA, a marker of myoepithelial cells, was detected in the flattened cells surrounding the acini but not in the cells positive for FGF-6. The staining properties of secretory granules in acinar cells were also examined with periodic acid-Shiff (PAS) and alcian blue (AB). PAS-positive granules abundant in the late gestational stages (GD17 to PD0) began to be replaced with AB-positive mucous granules at early neonatal days (PD0-3), when the FGF-6/FGFR-4 expression was the strongest. These findings suggest that FGF-6/FGFR-4 might be involved in the changes of secretory granule content of acinar cells in the sublingual gland during the late gestational and early neonatal stages.
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Sakulsak N, Wakayama T, Hipkaeo W, Yamamoto M, Iseki S. Cloning and Characterization of a Novel Animal Lectin Expressed in the Rat Sublingual Gland. J Histochem Cytochem 2005; 53:1335-43. [PMID: 15923361 DOI: 10.1369/jhc.5a6618.2005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We cloned a rat gene that is expressed primarily in the sublingual gland and named the predicted 503 amino-acid protein SLAMP (sublingual acinar membrane protein). SLAMP has 63% homology with human ERGIC-53-like protein, a member of the family of animal L-type lectins. Using a cDNA probe for SLAMP mRNA and rabbit antisera against SLAMP, we examined the expression and localization of SLAMP in major rat organs and tissues. With both Northern and Western blot analyses, abundant expression of SLAMP was demonstrated predominantly in the sublingual gland, with single sizes of the mRNA and protein 1.8 kb and 50 kDa, respectively, but not in other organs or tissues, including the parotid and submandibular glands. With immunohistochemistry, SLAMP was localized to the mucous acinar cells, but not to the serous demilunes or the duct system. With immunoelectron microscopy, SLAMP was localized predominantly to regions corresponding to the ER-Golgi intermediate compartment. Besides the sublingual gland, SLAMP immunore-activity was also demonstrated in mucous cells of the minor salivary glands in oral cavity and of Brunner's glands in the duodenum. These results suggested that rat SLAMP plays a specific role in the early secretory pathway of glycoproteins in specific types of mucous cells.
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Affiliation(s)
- Natthiya Sakulsak
- Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-8640, Japan
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22
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Wang J, Laurie GW. Organogenesis of the exocrine gland. Dev Biol 2004; 273:1-22. [PMID: 15302594 DOI: 10.1016/j.ydbio.2004.05.025] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2004] [Revised: 04/06/2004] [Accepted: 05/15/2004] [Indexed: 11/16/2022]
Abstract
Morphogenesis of exocrine glands is a complex stepwise process of epithelial ingrowth, ductal elongation, ductal branching, and alveolar or acinar differentiation. Emerging from an increasing number of mouse gene knockout, dominant-negative, and antisense models is the identification of a remarkable collection of cell adhesion molecules, growth factors, and their receptors whose time-dependent contributions to glandular organogenesis are essential. Many have cryptically overlapping and interdependent but noncompensatory roles. Discoidin domain receptor 1 tyrosine kinase (DDR1) and the ErbB1 receptor of amphiregulin are, for example, required for ductal branching and elongation. Each is in turn dependent on the Wnt family of morphogenic factors for autophosphorylation or transactivation, respectively. Here we review the current cast of exocrine glandular morphogens, as a foundation for a global or systems biology appreciation of the interweaving signaling pathways that underlie mammalian glandular morphogenesis.
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Affiliation(s)
- Jiahu Wang
- Department of Cell Biology, University of Virginia, Charlottesville 22908-0732, USA
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da Cunha Lima M, Sottovia-Filho D, Cestari TM, Taga R. Morphometric characterization of sexual differences in the rat sublingual gland. Braz Oral Res 2004; 18:53-8. [PMID: 15273787 DOI: 10.1590/s1806-83242004000100010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The presence of morphological differences in the sublingual gland of male and female adult rats was determined by morphometry. Absolute and relative glandular mass was 21% lower and 31% higher, respectively, in females than in males. The fractions of glandular volume occupied by the mixed acini, intercalated ducts and striated ducts did not differ significantly between genders; however, their absolute volume was respectively 29, 42 and 58% higher in males. Despite the differences in the volume of these morphological compartments, the number of cells did not differ significantly between genders, except for the excretory duct compartment, for which a larger number was observed in males. With respect to cell volume, 13, 33 and 47% higher volumes were observed in males for mucous acinar cells and striated and excretory duct cells, respectively, while a 38% higher volume of serous demilune cells was observed for females. The surface-to-volume ratio of acini and striated ducts was respectively 16 and 35% higher in females. Based on these results, we conclude that the sublingual gland of female rats possesses smaller acini, and shorter ducts whose caliber is narrower, smaller mucous acinar and larger serous cells than the ones found in the male gland, indicating the presence of sexual dimorphism as well as suggesting sexual differences in the quality of the secreted product.
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Affiliation(s)
- Marta da Cunha Lima
- Department of Biological Sciences, School of Dentistry of Bauru, University of São Paulo
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Kikuchi KI, Aiyama S, Ikeda R, Matsuoka T, Takada K. Granule types and their morphological changes in terminal cluster and acinar cells in the late pre- and early postnatal rat sublingual gland. ACTA ACUST UNITED AC 2004; 277:209-15. [PMID: 14983515 DOI: 10.1002/ar.a.20003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The developmental characteristics of serous cells appearing in the rat sublingual gland from the late prenatal to the early postnatal period were investigated in this study. Particular attention was paid to the morphological changes observed in the secretory granules at the histochemical and ultrastructural level. On prenatal day 18, granules with homogeneous high electron density (Type I granules), and mottled granules (Type II granules) with heterogeneous electron density appeared in the narrow luminar cytoplasm of cells constituting the terminal clusters. On prenatal day 19, these granules decreased in number and were replaced by bipartite granules (Type III granules) composed of a highly electron-dense core and a more electron-lucent rim. Pronase treatment almost completely digested the Type I and II granules and the electron-dense core of the Type III granules, although some of the Type I and II granules in serous demilunes at a later stage were insufficiently digested. On prenatal day 19.5, homogeneous granules of low electron density (Type IV granules) appeared in the terminal clusters and acini, and increased in number daily, making up 92.8% of the total granules on postnatal day 28. The granule morphology on electron microscopy, Alcian blue, and periodic acid-Schiff staining strongly suggested that Type I and II granules were serous granules, Type IV granules were mucous granules, and Type III granules were transforming-type granules. None of the secretory cells showed chromatin condensation, which is a characteristic of apoptosis. These findings suggest that the developing rat sublingual gland from the late prenatal to early postnatal period has numerous serous granules in the terminal clusters and acini, and that the majority of granules are replaced by mucous granules through transforming-type granules. In addition, because apoptotic figures of secretory cells could not be detected, it appears that most of the serous cells in the developing rat sublingual gland might have changed to mucous cells.
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Affiliation(s)
- Ken-Ichiro Kikuchi
- Department of Histology, The Nippon Dental University School of Dentistry at Tokyo, Japan.
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Fallon MA, Latchney LR, Hand AR, Johar A, Denny PA, Georgel PT, Denny PC, Culp DJ. The sld mutation is specific for sublingual salivary mucous cells and disrupts apomucin gene expression. Physiol Genomics 2003; 14:95-106. [PMID: 12847143 DOI: 10.1152/physiolgenomics.00151.2002] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
NFS/N-sld mice harbor a spontaneous autosomal recessive mutation, sld (sublingual gland differentiation arrest) and histologically display attenuated mucous cell expression in sublingual glands (Hayashi et al. Am J Pathol 132: 187-191, 1988). Because altered serous demilune cell expression is unknown, we determined the phenotypic expression of this cell type in mutants. Moreover, we evaluated whether absence of glycoconjugate staining in 3-day-old mutant glands is related to disruption in apomucin gene expression and/or to posttranslational glycosylation events. Serous cell differentiation is unaffected, determined morphologically and by serous cell marker expression (PSP, parotid secretory protein; and Dcpp, demilune cell and parotid protein). Conversely, apical granules in "atypical" exocrine cells of mutant glands are PSP and mucin negative, but contain abundant SMGD (mucous granule marker). Age-related appearance of mucous cells is associated with expression of apomucin gene products, whereas SMGD expression is unaltered. "Atypical" cells thus appear specified to a mucous cell fate but do not synthesize mucin glycoproteins unless selectively induced postnatally, indicating the sld mutation disrupts apomucin transcriptional regulation and/or decreases apomucin mRNA stability.
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Affiliation(s)
- M A Fallon
- University of Rochester Medical Center, Center for Oral Biology and the Department of Pharmacology and Physiology, Rochester, New York 14642-8611, USA
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Abstract
MECs are distributed on the basal aspect of the intercalated duct and acinus of human and rat salivary glands. However, they do not occur in the acinus of rat parotid glands, and sometimes occur in the striated duct of human salivary glands. MECs, as the name implies, have structural features of both epithelial and smooth muscle cells. They contract by autonomic nervous stimulation, and are thought to assist the secretion by compressing and/or reinforcing the underlying parenchyma. MECs can be best observed by immunocytochemistry. There are three types of immunocytochemical markers of MECs in salivary glands. The first type includes smooth muscle protein markers such as alpha-SMA, SMMHC, h-caldesmon and basic calponin, and these are expressed by MECs and the mesenchymal vasculature. The second type is expressed by MECs and the duct cells and includes keratins 14, 5 and 17, alpha 1 beta 1 integrin, and metallothionein. Vimentin is the third type and, in addition to MECs, is expressed by the mesenchymal cells and some duct cells. The same three types of markers are used for studying the developing gland. Development of MECs starts after the establishment of an extensively branched system of cellular cords each of which terminates as a spherical cell mass, a terminal bud. The pluripotent stem cell generates the acinar progenitor in the terminal bud and the ductal progenitor in the cellular cord. The acinar progenitor differentiates into MECs, acinar cells and intercalated duct cells, whereas the ductal progenitor differentiates into the striated and excretory duct cells. Both in the terminal bud and in the cellular cord, the immediate precursors of all types of the epithelial cells appear to express vimentin. The first identifiable MECs are seen at the periphery of the terminal bud or the immature acinus (the direct progeny of the terminal bud) as somewhat flattened cells with a single cilium projecting toward them. They express vimentin and later alpha-SMA and basic calponin. At the next developmental stage, MECs acquire cytoplasmic microfilaments and plasmalemmal caveolae but not as much as in the mature cell. They express SMMHC and, inconsistently, K14. This protein is consistently expressed in the mature cell. K14 is expressed by duct cells, and vimentin is expressed by both mesenchymal and epithelial cells. After development, the acinar progenitor and the ductal progenitor appear to reside in the acinus/intercalated duct and the larger ducts, respectively, and to contribute to the tissue homeostasis. Under unusual conditions such as massive parenchymal destruction, the acinar progenitor contributes to the maintenance of the larger ducts that result in the occurrence of striated ducts with MECs. The acinar progenitor is the origin of salivary gland tumors containing MECs. MECs in salivary gland tumors are best identified by immunocytochemistry for alpha-SMA. There are significant numbers of cells related to luminal tumor cells in the non-luminal tumor cells that have been believed to be neoplastic MECs.
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Affiliation(s)
- Yuzo Ogawa
- Department of Oral Pathology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
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Miyazaki T, Inoue Y, Takano K. Comparative Study of the Proliferative Activity of Serous- and Mucous-type Acinar Cells in Developing Mongolian Gerbil Mixed Salivary Glands. Acta Histochem Cytochem 2002. [DOI: 10.1267/ahc.35.343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Toshihiro Miyazaki
- Division of Oral Cytology and Cell Biology, Department of Developmental Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Science
| | - Yasuhisa Inoue
- Faculty of Wellness studies, Department of Nutritional Health (Anatomy and Physiology), Kwassui Women's College
| | - Kunio Takano
- Division of Oral Cytology and Cell Biology, Department of Developmental Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Science
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