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Gao X, Mukaibo T, Wei X, Faustoferri RC, Oei MS, Hwang SK, Yan AJ, Melvin JE, Ovitt CE. Nkx2.3 transcription factor is a key regulator of mucous cell identity in salivary glands. Dev Biol 2024; 509:1-10. [PMID: 38311164 PMCID: PMC10939741 DOI: 10.1016/j.ydbio.2024.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/23/2024] [Accepted: 01/30/2024] [Indexed: 02/10/2024]
Abstract
Saliva is vital to oral health, fulfilling multiple functions in the oral cavity. Three pairs of major salivary glands and hundreds of minor salivary glands contribute to saliva production. The secretory acinar cells within these glands include two distinct populations. Serous acinar cells secrete a watery saliva containing enzymes, while mucous acinar cells secrete a more viscous fluid containing highly glycosylated mucins. Despite their shared developmental origins, the parotid gland (PG) is comprised of only serous acinar cells, while the sublingual gland (SLG) contains predominantly mucous acinar cells. The instructive signals that govern the identity of serous versus mucous acinar cell phenotypes are not yet known. The homeobox transcription factor Nkx2.3 is uniquely expressed in the SLG. Disruption of the Nkx2.3 gene was reported to delay the maturation of SLG mucous acinar cells. To examine whether Nkx2.3 plays a role in directing the mucous cell phenotype, we analyzed SLG from Nkx2.3-/- mice using RNAseq, immunostaining and proteomic analysis of saliva. Our results indicate that Nkx2.3, most likely in concert with other transcription factors uniquely expressed in the SLG, is a key regulator of the molecular program that specifies the identity of mucous acinar cells.
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Affiliation(s)
- Xin Gao
- Secretory Mechanisms and Dysfunctions Section, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Xiaolu Wei
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Roberta C Faustoferri
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Maria S Oei
- Secretory Mechanisms and Dysfunctions Section, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Seo-Kyoung Hwang
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Adela Jingyi Yan
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - James E Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Catherine E Ovitt
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA; Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA.
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Yamashita S, Kondo Y, Watanabe C, Nodai T, Munemasa T, Mukaibo T, Masaki C, Shibata Y, Hosokawa R. Chronic kidney disease compromises structural and mechanical properties of maxillary cortical bone in a rat model. J Prosthodont Res 2024; 68:264-272. [PMID: 37211410 DOI: 10.2186/jpr.jpr_d_23_00016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PURPOSE This study aimed to investigate the effects of chronic kidney disease (CKD) on the structural and mechanical properties of the maxillary and mandibular cortical bone. METHODS The maxillary and mandibular cortical bones from CKD model rats were used in this study. CKD-induced histological, structural, and micro-mechanical alterations were assessed using histological analyses, micro-computed tomography (CT), bone mineral density (BMD) measurements, and nanoindentation tests. RESULTS Histological analyses indicated that CKD caused an increase in the number of osteoclasts and a decrease in the number of osteocytes in the maxilla. Micro-CT analysis revealed that CKD induced a void volume/cortical volume (%) increase, which was more remarkable in the maxilla than in the mandible. CKD also significantly decreased the BMD in the maxilla. In the nanoindentation stress-strain curve, the elastic-plastic transition point and loss modulus were lower in the CKD group than that in the control group in the maxilla, suggesting that CKD increased micro fragility of the maxillary bone. CONCLUSIONS CKD affected bone turnover in the maxillary cortical bone. Furthermore, the maxillary histological and structural properties were compromised, and micro-mechanical properties, including the elastic-plastic transition point and loss modulus, were altered by CKD.
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Affiliation(s)
- Sotaro Yamashita
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Chie Watanabe
- Department of Biomaterials and Engineering, Showa University School of Dentistry, Tokyo, Japan
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Yo Shibata
- Department of Biomaterials and Engineering, Showa University School of Dentistry, Tokyo, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
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Mukaibo T, Yamada M. Evaluation of Rheological Properties of Saliva by Determining the Spinnbarkeit. Methods Mol Biol 2024; 2763:395-401. [PMID: 38347429 DOI: 10.1007/978-1-0716-3670-1_34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
Saliva is crucial to maintaining oral health and facilitating chewing, swallowing, and speech functions. Decreased saliva secretion, known as hyposalivation, impairs these functions and increases the risk of dental caries and other infectious diseases in the oral cavity.Saliva exhibits various rheological properties, with mucin being a factor in determining these properties. Alterations in these properties can also affect the sensation of dry mouth. In this article, we focus on the spinnbarkeit of saliva using the Neva Meter instrument and provide a methodology for fully understanding the appropriate conditions for its use.
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Affiliation(s)
- Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan.
| | - Mikio Yamada
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
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Kondo Y, Masaki C, Mukaibo T, Yano HT, Iwasaki M, Hosokawa R. 5- to 15-Year Survival of Immediately Loaded Implants in Fully Edentulous Maxillae: A Multilevel Analysis in a Retrospective Cohort Study. Int J Oral Maxillofac Implants 2023; 38:516-522. [PMID: 37279219 DOI: 10.11607/jomi.10310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Abstract
PURPOSE Although immediate-loading implant (ILI) treatment is a general treatment strategy for fully edentulous maxillae, long-term evidence is required. The purpose of this study was to evaluate the long-term clinical results of, and risk factors for, ILI treatment in fully edentulous maxillae. MATERIALS AND METHODS ILI treatments of maxillae using 526 implants in 117 patients were reviewed retrospectively. The longest and mean observation periods were 15 years and 9.2 years, respectively. Kaplan-Meier survival curve analysis, log-rank tests, and multilevel mixed-effects parametric survival analysis were used for statistical analyses. RESULTS Overall, 38 of 526 implants failed in 23 patients, and the estimated 15-year cumulative implant-level and patient-level survival rates were 90.7% and 73.7%, respectively. The cumulative implant survival rate was significantly higher in female patients than in male patients. Sex, implant length, and implant diameter were significantly associated with implant survival. CONCLUSION ILI treatment of completely edentulous maxillae demonstrated viable long-term clinical outcomes. Male sex, shorter implant length, and narrow implant diameter negatively affected implant survival. Int J Oral Maxillofac Implants 2023;38:516-522. doi: 10.11607/jomi.10310.
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Yamada M, Masaki C, Mukaibo T, Munemasa T, Nodai T, Kondo Y, Hosokawa R. Altered Rheological Properties of Saliva with Aging in Mouse Sublingual Gland. J Dent Res 2022; 101:942-950. [PMID: 35238237 DOI: 10.1177/00220345221076071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mucin in saliva plays a critical role in the hydration and lubrication of the oral mucosa by retaining water molecules, and its impaired function may be associated with hyposalivation-independent xerostomia. Age-dependent effects on salivary gland function and rheological properties of secreted saliva are not fully understood as aging is a complex and multifactorial process. We aimed to evaluate age-related changes in the rheological properties of saliva and elucidate the underlying mechanism. We performed ex vivo submandibular gland (SMG) and sublingual gland (SLG) perfusion experiments to collect saliva from isolated glands of young (12 wk old) and aged (27 mo old) female C57BL/6J mice and investigate the rheological properties by determining the spinnbarkeit (viscoelasticity). While fluid secretion was comparable in SMG and SLG of both mice, spinnbarkeit showed a significant decrease in SLG saliva of aged mice than that of young mice. There were no significant differences in GalNAc concentration between young and aged SLG saliva. Liquid chromatography/tandem mass spectrometry analysis of SLG saliva revealed that (Hex)1 (HexNAc)1 (NeuAc)1 at m/z 793.31 was the most abundant O-glycan structure in SLG saliva commonly detected in both mice. Lectin staining of salivary gland tissue showed that SLG stained strongly with Maackia amurensis lectin II (MAL II) while Sambucus nigra agglutinin (SNA) stained little, if any, SLG. The messenger RNA expression of St3gal1 that encodes an α-2,3 sialic acid sialyltransferase SIAT4-A showed a decrease in SLG of aged mice, confirmed by a Western blot analysis. Lectin blot analysis in SLG saliva revealed that the relative signal intensity detected by MAL II was significantly lower in aged SLG. Our results suggest that spinnbarkeit decreases in SLG of aging mice due to downregulation of sialic acid linked to α-2,3 sialic acid sialyltransferase expression.
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Affiliation(s)
- M Yamada
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - C Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - T Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - Y Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - R Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
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Thongpoung S, Masaki C, Nodai T, Munemasa T, Mukaibo T, Kondo Y, Hosokawa R. A new mandibular deformation index predicts amount of bone deformation in edentulous patients treated with an implant-supported fixed prosthesis. J Prosthodont Res 2021; 66:582-588. [PMID: 34924491 DOI: 10.2186/jpr.jpr_d_21_00145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE The present study was performed to examine the mandibular deformation during mouth opening in edentulous patients, treated with an implant-supported fixed prosthesis using strain gauges, and identify factors affecting deformation. METHODS Twenty patients with a fully edentulous mandible who received either 4 or ≥6 implants were included. The distal-most implants were placed mesial to the mental foramen (premolar region) in patients with 4 implants and distal to the mental foramen (molar region) in patients with ≥6 implants. Mandibular deformation during mouth opening was measured using strain gauges in two directions: anteroposterior direction and lateral direction between the distal-most implants on the left and right sides (arch width). The mandibular anatomy was evaluated using computed tomography. RESULTS Arch width reduction between the left and right implants during mouth opening ranged from 47.38 to 512.80 µm; the range of deformation was 0.12 to 15.14 µm in the anteroposterior direction. Furthermore, a significant positive correlation was noted between arch width reduction in the premolar region and the ratio between the symphyseal bone height and width (P = 0.0003, r = 0.72). CONCLUSION The reduction in arch width was higher in the molar region than in the premolar region during mouth opening. Moreover, the reduction could be high in the mandibular symphyseal bone because of its greater height and lesser width. The ratio between the symphyseal bone height and width is defined as the mandibular deformation index (MDI) and is used to predict the rate of mandibular bone deformation.
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Affiliation(s)
- Sirapat Thongpoung
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan.,Department of Prosthodontics, College of Dental Medicine, Rangsit University, Pathum Thani, Thailand
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University Graduate School, Japan
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Iwamoto D, Masaki C, Shibata Y, Watanabe C, Nodai T, Munemasa T, Mukaibo T, Kondo Y, Hosokawa R. Microstructural and mechanical recovery of bone in ovariectomized rats: The effects of menaquinone-7. J Mech Behav Biomed Mater 2021; 120:104571. [PMID: 34029943 DOI: 10.1016/j.jmbbm.2021.104571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/28/2021] [Accepted: 05/02/2021] [Indexed: 10/21/2022]
Abstract
The loss of bone quantity and quality in postmenopausal female patients can be a problem for dental treatment. A sufficient intake of nutrients such as calcium, magnesium, and vitamins D and K is likely correlated with the mechanical properties of bone. In particular, vitamin K2, also called menaquinone (MK), inhibits bone loss in postmenopausal women. Here we demonstrate the microstructural and mechanical properties of bone recovery in ovariectomized (OVX) rats during MK-7 administration. Bilateral ovariectomy and a sham operation were performed on 14-week-old female SPF Wistar rats. MK-4 and -7 were orally administered at 30 mg/kg daily for 12 weeks. The femur was used for the 3-point bending test and microstructural analysis of the cancellous bone by micro-CT, and the mandibular cortical bone for the evaluation of mechanical properties on a nanoscale. Micro-computed tomography revealed irregular trabecular architecture, hollow marrow cavities, and sparse trabecular bone in the femurs of the OVX group. Trabecular bone structure analysis showed that the MK-7 group had greater bone volume per tissue volume (BV/TV) and a higher trabecular number than the OVX group. The bulk-scale 3-point bending test did not allow the mechanical properties between OVX and OVX/MK7 groups to be discerned, yet at the smallest level, the elastic-plastic transition point of the nanoindentation stress-strain curve of the mandibular cortical bone was higher in the MK-7 group than in the OVX group. These findings suggest that MK-7 enables bone microstructural and mechanical recovery in the OVX model.
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Affiliation(s)
- Daisei Iwamoto
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan.
| | - Yo Shibata
- Department of Conservative Dentistry, Division of Biomaterials and Engineering, Showa University School of Dentistry, Japan
| | - Chie Watanabe
- Department of Conservative Dentistry, Division of Biomaterials and Engineering, Showa University School of Dentistry, Japan
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
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8
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Nakagawa T, Tsuka S, Aonuma F, Nodai T, Munemasa T, Tamura A, Mukaibo T, Kondo Y, Masaki C, Hosokawa R. Effects of metformin on the prevention of bisphosphonate-related osteonecrosis of the jaw-like lesions in rats. J Prosthodont Res 2020; 65:219-224. [PMID: 32938854 DOI: 10.2186/jpr.jpor_2019_629] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE In this study, we aimed to investigate the effect of glucose metabolism on bone healing after tooth extraction in an osteoporosis rat model administered zoledronic acid (ZA) and dexamethasone (DX). METHODS In total, 24 male Wistar rats (4 weeks old) were randomly assigned to four groups: Control (subcutaneous physiological saline), ZD (subcutaneous ZA and DX twice a week), Ins+ZD (subcutaneous insulin followed by ZD treatment), and Met+ZD (oral metformin followed by ZD treatment). Blood was collected every two weeks . Two weeks after treatment initiation, the first molar tooth on the right maxilla was extracted from all rats. Four weeks later, the rats were sacrificed, and bone healing was assessed. Maxillae samples were fixed and scanned using micro-computed tomography for quantifying areas of bone defects. Hematoxylin-eosin and tartrate-resistant acid phosphatase (TRAP) staining were performed to evaluate bone apoptosis and osteoclast number. RESULTS In all experimental groups, body weight was statistically lower than that in the Control group, with no changes observed in uncarboxylated osteocalcin concentrations. The radiological analysis revealed that insulin or metformin administration improved healing in the tooth extraction socket (p < 0.01). Histological examination revealed that the osteonecrosis area was reduced in the Ins+ZD and Met+ZD groups (p < 0.01). TRAP staining presented increased osteoclast numbers in the ZD group when compared with that observed in the Control. CONCLUSIONS Tooth extraction with long-term ZA and DX administration inhibited bone remodeling and induced bisphosphonate-related osteonecrosis of the jaw-like lesions. Metformin exerted protective effects ag ainst osteonecrosis of the jaw.
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Affiliation(s)
- Tomohito Nakagawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Fumiko Aonuma
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Akiko Tamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka
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Monir A, Abd El-Aal AB, Omar M, El-Shair M, Mukaibo T, Hosokawa R. The Viability and Cytotoxic Effect of High Mobility Group Box Protein 1 on MC3T3-E1 Pre-osteoblast Cells: an In Vitro Study. Zagazig Veterinary Journal 2020; 48:254-262. [DOI: 10.21608/zvjz.2020.27091.1106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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10
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Munemasa T, Gao X, Melvin JE, Mukaibo T. Ano6 disruption impairs acinar cell regulatory volume decrease and protein secretion in murine submandibular salivary glands. J Cell Physiol 2020; 235:8533-8545. [PMID: 32329061 DOI: 10.1002/jcp.29697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 03/24/2020] [Accepted: 03/29/2020] [Indexed: 11/09/2022]
Abstract
The widely expressed Anoctamin 6 (Ano6) supports different Ca2+ -dependent functions, but little is known about its role in salivary glands. Mouse submandibular gland (SMG) acinar cells exhibited a robust regulatory volume decrease (RVD) following cell swelling that was reduced approximately 70% in Ano6-/- mice. Ca2+ -free conditions nearly eliminated the RVD response suggesting that Ano6 is an obligatory component of the cell volume-activated, Ca2+ -dependent RVD pathway in salivary gland acinar cells. Ex vivo agonist-stimulated secretion of water and ions was unaffected by Ano6 disruption under both isotonic and hypotonic conditions suggesting that Ano6 does not play a major role in fluid and electrolyte secretion. In contrast, the total amount of β-adrenergic-dependent protein secretion by the SMG was significantly reduced in Ano6-/- mice. Closer inspection of these latter results revealed that protein secretion was affected only in the female SMG by Ano6 disruption. These results indicate that Ano6 modulates the RVD response and protein secretion by salivary gland acinar cells.
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Affiliation(s)
- Takashi Munemasa
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland.,Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - Xin Gao
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - James E Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland.,Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
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11
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Peluso G, Tian E, Abusleme L, Munemasa T, Mukaibo T, Ten Hagen KG. Loss of the disease-associated glycosyltransferase Galnt3 alters Muc10 glycosylation and the composition of the oral microbiome. J Biol Chem 2020; 295:1411-1425. [PMID: 31882545 PMCID: PMC6996895 DOI: 10.1074/jbc.ra119.009807] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 12/20/2019] [Indexed: 12/26/2022] Open
Abstract
The importance of the microbiome in health and its disruption in disease is continuing to be elucidated. However, the multitude of host and environmental factors that influence the microbiome are still largely unknown. Here, we examined UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase 3 (Galnt3)-deficient mice, which serve as a model for the disease hyperphosphatemic familial tumoral calcinosis (HFTC). In HFTC, loss of GALNT3 activity in the bone is thought to lead to altered glycosylation of the phosphate-regulating hormone fibroblast growth factor 23 (FGF23), resulting in hyperphosphatemia and subdermal calcified tumors. However, GALNT3 is expressed in other tissues in addition to bone, suggesting that systemic loss could result in other pathologies. Using semiquantitative real-time PCR, we found that Galnt3 is the major O-glycosyltransferase expressed in the secretory cells of salivary glands. Additionally, 16S rRNA gene sequencing revealed that the loss of Galnt3 resulted in changes in the structure, composition, and stability of the oral microbiome. Moreover, we identified the major secreted salivary mucin, Muc10, as an in vivo substrate of Galnt3. Given that mucins and their O-glycans are known to interact with various microbes, our results suggest that loss of Galnt3 decreases glycosylation of Muc10, which alters the composition and stability of the oral microbiome. Considering that oral findings have been documented in HFTC patients, our study suggests that investigating GALNT3-mediated changes in the oral microbiome may be warranted.
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MESH Headings
- Animals
- Calcinosis/genetics
- Calcinosis/metabolism
- Calcinosis/microbiology
- Female
- Fibroblast Growth Factor-23
- Glycosylation
- Glycosyltransferases/metabolism
- Hyperostosis, Cortical, Congenital/genetics
- Hyperostosis, Cortical, Congenital/metabolism
- Hyperostosis, Cortical, Congenital/microbiology
- Hyperphosphatemia/genetics
- Hyperphosphatemia/metabolism
- Hyperphosphatemia/microbiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microbiota/genetics
- Mucins/chemistry
- Mucins/metabolism
- N-Acetylgalactosaminyltransferases/genetics
- N-Acetylgalactosaminyltransferases/metabolism
- Polysaccharides/metabolism
- RNA, Ribosomal, 16S/genetics
- Salivary Glands/metabolism
- Polypeptide N-acetylgalactosaminyltransferase
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Affiliation(s)
- Gabriella Peluso
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - E Tian
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Loreto Abusleme
- Laboratory of Oral Microbiology, Faculty of Dentistry, University of Chile, Santiago 8380544, Chile
- Laboratory of Craniofacial Translational Research, Faculty of Dentistry, University of Chile, Santiago 8380544, Chile
| | - Takashi Munemasa
- Secretory Mechanisms and Dysfunctions Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Kelly G Ten Hagen
- Developmental Glycobiology Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
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12
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Peluso G, Tian E, Abusleme L, Munemasa T, Mukaibo T, Ten Hagen KG. Loss of the disease-associated glycosyltransferase Galnt3 alters Muc10 glycosylation and the composition of the oral microbiome. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49899-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Yamazaki S, Masaki C, Nodai T, Tsuka S, Tamura A, Mukaibo T, Kondo Y, Ono K, Hosokawa R. The effects of hyperglycaemia on peri-implant tissues after osseointegration. J Prosthodont Res 2019; 64:217-223. [PMID: 31852608 DOI: 10.1016/j.jpor.2019.07.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 05/23/2019] [Accepted: 07/16/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE We assessed the effects of hyperglycaemia induced by streptozotocin (STZ) on peri-implantitis developing after implant osseointegration. METHODS Thirty-six male Wistar rats (4 weeks old) were used. We placed titanium implants 4 weeks after extraction of the maxillary first molars. Healing abutments were attached 4 weeks later. After osseointegration was confirmed, the rats were divided into control, hyperglycaemia (STZ), and STZ with insulin (STZ+INS) groups. Hyperglycaemia was induced by a single injection of 50mg/kg STZ. Silk ligatures were placed on only the right sides (i.e. ligature sides), not on the left sides. Peri-implant tissues extracted at 4 weeks post-ligation were analysed both radiologically (via micro-computed tomography) and histologically (via toluidine blue staining). Total RNA was also extracted and analysed by quantitative PCR to detect TNF-α, IL-1β and the receptor of advanced glycation end products (RAGE). Additionally, advanced glycation end products (AGEs) were measured by ELISA. RESULTS Radiological and histological analyses showed that bone loss on the non-ligature sides was significantly greater in the STZ than the control group. However, on the ligature sides, bone loss was greater than on the non-ligature sides, and no significant difference was evident among the three groups. The levels of mRNAs encoding TNF-α, IL-1β, RAGE, and AGEs on the ligature sides were significantly upregulated (all P<0.05) in the STZ compared to the control group. CONCLUSIONS Although hyperglycaemia could be associated with bone loss around implants with increased AGE production and RAGE expression, hyperglycaemia does not become a triggering factor of ligature induced peri-implantitis.
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Affiliation(s)
- Seiya Yamazaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan.
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Akiko Tamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Kentaro Ono
- Division of Physiology, Kyushu Dental University, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
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Yang N, Mukaibo T, Gao X, Kurtz I, Melvin JE. Slc4a11 disruption causes duct cell loss and impairs NaCl reabsorption in female mouse submandibular glands. Physiol Rep 2019; 7:e14232. [PMID: 31833218 PMCID: PMC6908739 DOI: 10.14814/phy2.14232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 12/11/2022] Open
Abstract
Slc4a11, a member of the Slc4 HCO3- transporter family, has a wide tissue distribution. In mouse salivary glands, the expression of Slc4a11 mRNA was more than eightfold greater than the other nine members of the Slc4 gene family. The Slc4a11 protein displayed a diffuse subcellular distribution in both the acinar and duct cells of mouse submandibular glands (SMG). Slc4a11 disruption induced a significant increase in the Na+ and Cl- concentrations of stimulated SMG saliva, whereas it did not affect the fluid secretion rate in response to either β-adrenergic or cholinergic receptor stimulation. Heterologous expressed mouse Slc4a11 acted as a H+ /OH- transporter that was uncoupled of Na+ or Cl- movement, and this activity was blocked by ethyl-isopropyl amiloride (EIPA) but not 4,4'-Diisothiocyanato-2,2'-stilbenedisulfonic acid (DIDS). Slc4a11 disruption revealed that Slc4a11 does not play a major role in intracellular pH regulation in mouse salivary gland cells. In contrast, NaCl reabsorption was impaired in the SMG saliva of female compared to male Slc4a11 null mice, which correlated with the loss of duct cells and a decrease in expression of the duct-cell-specific transcription factor Ascl3. Together, our results suggest that Slc4a11 expression regulates the number of ducts cells in the mouse SMG and consequently NaCl reabsorption.
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Affiliation(s)
- Ning‐Yan Yang
- Secretory Mechanisms and Dysfunctions SectionNational Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMaryland
- Department of Pediatric DentistryBeijing Stomatological Hospital & School of StomatologyCapital Medical UniversityBeijingChina
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions SectionNational Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMaryland
- Division of Oral Reconstruction and RehabilitationKyushu Dental UniversityKitakyushuFukuokaJapan
| | - Xin Gao
- Secretory Mechanisms and Dysfunctions SectionNational Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMaryland
| | - Ira Kurtz
- Department of MedicineDivision of NephrologyDavid Geffen School of Medicine, and the Brain Research InstituteUniversity of CaliforniaLos AngelesCalifornia
| | - James E. Melvin
- Secretory Mechanisms and Dysfunctions SectionNational Institute of Dental and Craniofacial ResearchNational Institutes of HealthBethesdaMaryland
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15
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Munemasa T, Mukaibo T, Melvin JE. Slc26a6 is an apical membrane anion exchanger that drives HCO 3--dependent fluid secretion in murine pancreatic acinar cells. Am J Physiol Cell Physiol 2019; 317:C1153-C1160. [PMID: 31532720 PMCID: PMC6957380 DOI: 10.1152/ajpcell.00257.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 11/22/2022]
Abstract
The nonselective anion exchanger Slc26a6, also known as putative anion transporter 1 and chloride/formate exchanger, is thought to play a major role in HCO 3 - transport in exocrine glands. In this study, Slc26a6 null mice were used to explore the function of Slc26a6 in the exocrine pancreas. Slc26a6 primarily localized to the apical membrane of pancreatic exocrine acinar cells. The volume of stimulated juice secretion by the ex vivo pancreas was significantly reduced ~35% in Slc26a6-/- mice, but no changes occurred in the gross structure or gland weights of Slc26a6 null mice. The secretion of pancreatic juice by Slc26a6+/+ mice was dependent on HCO 3 - while, in contrast, fluid secretion by Slc26a6-/- mice was independent of HCO 3 - , suggesting that Slc26a6 mediates the HCO 3 - -dependent component of fluid secretion. Consistent with these observations, disruption of Slc26a6 also significantly reduced HCO 3 - secretion by the pancreas ~35%. Taken together, these results demonstrate that the apical Slc26a6 anion exchanger in acinar cells is involved in HCO 3 - -dependent fluid secretion but that another major HCO 3 - -independent pathway is the primary driver of the fluid secretion process in the mouse pancreas.
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Affiliation(s)
- Takashi Munemasa
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - James E Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland
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16
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Yang NY, Mukaibo T, Kurtz I, Melvin JE. The apical Na + -HCO 3 - cotransporter Slc4a7 (NBCn1) does not contribute to bicarbonate transport by mouse salivary gland ducts. J Cell Physiol 2019; 234:16376-16388. [PMID: 30767201 PMCID: PMC6694005 DOI: 10.1002/jcp.28306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/05/2019] [Accepted: 01/18/2019] [Indexed: 01/25/2023]
Abstract
The HCO3 - secretion mechanism in salivary glands is unclear but is thought to rely on the co-ordinated activity of multiple ion transport proteins including members of the Slc4 family of bicarbonate transporters. Slc4a7 was immunolocalized to the apical membrane of mouse submandibular duct cells. In contrast, Slc4a7 was not detected in acinar cells, and correspondingly, Slc4a7 disruption did not affect fluid secretion in response to cholinergic or β-adrenergic stimulation in the submandibular gland (SMG). Much of the Na + -dependent intracellular pH (pH i ) regulation in SMG duct cells was insensitive to 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid, S0859, and to the removal of extracellular HCO 3 - . Consistent with these latter observations, the Slc4a7 null mutation had no impact on HCO 3 - secretion nor on pH i regulation in duct cells. Taken together, our results revealed that Slc4a7 targets to the apical membrane of mouse SMG duct cells where it contributes little if any to pH i regulation or stimulated HCO 3 - secretion.
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Affiliation(s)
- Ning-Yan Yang
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA,Department of Pediatric Dentistry, Beijing Stomatological Hospital & School of Stomatology, Capital Medical University, Beijing, 100050, China
| | - Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA,Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Ira Kurtz
- Department of Medicine, Division of Nephrology, David Geffen School of Medicine, and the Brain Research Institute, University of California, Los Angeles, CA, 90095, USA
| | - James E. Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
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Kawamura M, Masaki C, Shibata Y, Kondo Y, Mukaibo T, Miyazaki T, Hosokawa R. Pentosidine correlates with nanomechanical properties of human jaw bone. J Mech Behav Biomed Mater 2019; 98:20-25. [PMID: 31176091 DOI: 10.1016/j.jmbbm.2019.06.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/28/2019] [Accepted: 06/03/2019] [Indexed: 01/22/2023]
Abstract
Initial intimate apposition between implant fixtures and host bone at the surgical site is a critical factor for osseointegration of dental implants. The advanced glycation end products accumulated in the jaw bone could lead to potential failure of a dental implant during the initial integration stage, because of the inferior bone mechanical property associated with the abnormal collagen cross-linking at the material level. Here, we demonstrate the lowered creep deformation resistance and reduced dimensional recovery of jaw bone in line with high levels of pentosidine accumulation in the bone matrix which likely correlate with the pentosidine level in blood plasma. Peripheral blood samples and cortical bone samples at the surgical site were obtained from patients scheduled for dental implants in the mandible. The pentosidine levels in blood plasma were assessed. Subsequently, the relative pentosidine levels and the mechanical properties of the jaw bone were quantified by Raman microspectroscopy and nanoindentation, respectively. The nanoindentation tests revealed less creep deformation resistance and reduced time-dependent dimensional recovery of bone samples with the increase in the relative pentosidine level in the bone matrix. Higher tan δ values at the various frequencies during the dynamic indentation tests also suggested that viscoelasticity is associated with the relative intensity of pentosidine in the jaw bone matrix. We found a positive correlation between the pentosidine levels in blood plasma and the bone matrix, which in turn reduced the mechanical property of the jaw bone at the material level. Increased creep and reduced dimensional recovery of the jaw bone may diminish the mechanical interlocking of dental implants during the initial integration stage. Given the likely correlation between the plasma pentosidine level and the mechanical properties of bone, measurement of the plasma pentosidine level could serve as a new index to assess jaw bone matrix quality in advance of implant surgery.
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Affiliation(s)
- Michihiko Kawamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu, Fukuoka, 803-8580, Japan.
| | - Yo Shibata
- Department of Conservative Dentistry, Division of Biomaterials and Engineering, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Takashi Miyazaki
- Department of Conservative Dentistry, Division of Biomaterials and Engineering, Showa University School of Dentistry, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, 142-8555, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-ku, Kitakyushu, Fukuoka, 803-8580, Japan
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18
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Nagao M, Masaki C, Nakao M, Ito Y, Tsuka S, Mukaibo T, Kondo Y, Hosokawa R. Is Anterior Guidance a Key Factor on Planning Implant Treatment for Free-End Missing in the Posterior Mandible? J ORAL IMPLANTOL 2019; 45:100-105. [DOI: 10.1563/aaid-joi-d-17-00237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To perform safe implant treatment, the anatomical structure and bone quality at implant placement sites are evaluated based on a patient's computerized tomography (CT) data, but there is no definite method to determine placement sites and the appropriate number of implants. The objective of this study was to investigate the influence of the number and arrangement of implants on the stress distribution in 3-unit posterior fixed partial dentures for the posterior mandible by mechanical analysis using the finite element method. Three-dimensional finite element analysis models were constructed from the CT data of a patient with missing mandibular teeth (Nos. 35, 36, 37). Implant placement was simulated under various conditions. Superstructures were connected and fixed with a titanium frame. As the loading conditions, 400 N vertical and lateral loads (45° on the lingual side and 45° on the buccal side) were applied to the upper areas of Nos. 35, 36, and 37, and the stress distribution and frame displacement were evaluated. When a vertical force was applied, no difference of the von Mises stress was noted among the 5 experimental conditions. When lateral force was applied from the lingual and buccal sides at 45°, the stress was higher than that induced by vertical force under all conditions, and it was especially high under mesial and distal cantilever conditions. When displacement of the titanium frame was measured, the displacement caused by lateral force was greater than that due to vertical force. In addition, comparison between long and short distal cantilever bridges revealed that displacement of the titanium frame tended to be smaller when the short cantilever was used. These findings suggested that the stress on peri-implant tissues and displacement of the titanium frame vary depending on the configuration and number of implants, with greater stress and more marked displacement of the titanium frame being induced by lateral force when the number of implants is reduced and a cantilever bridge is selected.
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Affiliation(s)
- Mitsuharu Nagao
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
| | | | | | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Fukuoka, Japan
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Mukaibo T, Gao X, Yang NY, Oei MS, Nakamoto T, Melvin JE. Sexual dimorphisms in the transcriptomes of murine salivary glands. FEBS Open Bio 2019; 9:947-958. [PMID: 30998297 PMCID: PMC6487692 DOI: 10.1002/2211-5463.12625] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/05/2019] [Accepted: 03/17/2019] [Indexed: 12/25/2022] Open
Abstract
Transcriptional profiling identified 933 sexually dimorphic genes out of the 14 371 protein‐coding genes expressed in the three major murine salivary glands: parotid, sublingual, and submandibular. Most (89%) sex‐specific genes were enriched in a single gland, while only 0.5% of the sexually dimorphic genes were enriched in all glands. The sublingual gland displayed a strong male sex bias (94% of sex‐enriched genes), while a sex preference was not obvious in the parotid or submandibular glands. A subset of transcription factor genes was correlated with the expression of gland‐specific, sex‐enriched genes. Higher expression of Cftr chloride and Scnn1 sodium channels in the male submandibular correlated with greater NaCl reabsorption. In conclusion, adult salivary glands display sex‐ and gland‐specific differences in gene expression that reflect their unique functional properties.
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Affiliation(s)
- Taro Mukaibo
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, Japan
| | - Xin Gao
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Joint Institute for Food Safety and Applied Nutrition, University of Maryland, College Park, MD, USA
| | - Ning-Yan Yang
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.,Department of Pediatric Dentistry, Beijing Stomatological Hospital & School of Stomatology, Capital Medical University, Beijing, China
| | - Maria S Oei
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
| | - Tetsuji Nakamoto
- Department of Prosthodontics, Matsumoto Dental University, Shiojiri, Japan
| | - James E Melvin
- Secretory Mechanisms and Dysfunctions Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA
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20
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Maeda T, Mukaibo T, Masaki C, Thongpoung S, Tsuka S, Tamura A, Aonuma F, Kondo Y, Hosokawa R. Efficacy of electric-powered cleaning instruments in edentulous patients with implant-supported full-arch fixed prostheses: a crossover design. Int J Implant Dent 2019; 5:7. [PMID: 30911853 PMCID: PMC6434005 DOI: 10.1186/s40729-019-0164-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 01/23/2019] [Indexed: 11/16/2022] Open
Abstract
Background The aim of this study was to evaluate the plaque removal efficacies of electric toothbrushes and electric dental floss compared with conventional manual toothbrushing in cleaning the fitting surface of an All-on-4™ concept (Nobel Biocare, Zürich-Flughafen, Switzerland) implant-supported fixed dental prosthesis (FDP). Methods Nine patients with maxillary edentulous arches participated in the study. We investigated two electric-powered brushes (Sonicare Diamond Clean®, Koninklijke Philips N.V., Amsterdam, the Netherlands [SD group], and the Oral-B Professional Care Smart Series 5000®, Braun GmbH, Kronberg, Germany [OralB group]) and one electric dental floss unit (Air Floss®, Koninklijke Philips N.V. [AF group]). A manual toothbrush (Tuft24® MS, OralCare Inc., Tokyo, Japan) was used by the control group. The fitting surface of the FDP was stained to allow visualization of the entire accumulated plaque area. Both the buccal and palatal portions of the plaque area were assessed before and after brushing to evaluate each instrument’s plaque removal rate using a crossover study design. Two-week washout periods were employed between each evaluation. Results The plaque removal rates were 53.5 ± 8.5%, 70.9 ± 6.5%, 75.4 ± 6.3%, and 74.4 ± 4.2% for the control, AF, OralB, and SD groups, respectively. When participants were divided into two groups based on their plaque removal rates with a manual toothbrush (poor brushing and good brushing), the poor brushing group showed significant improvement in the plaque removal rate when using electric-powered toothbrushes. The plaque removal rates for the buccal area were significantly higher for the OralB and SD groups than for the manual brushing group (control group), with rates of 52.8 ± 7.9%, 70.1 ± 7.3%, 77.7 ± 6.5%, and 79.5 ± 3.7% for the control, AF, OralB, and SD groups, respectively. The plaque removal rates in the palatal area were consistently lower than those in the buccal area for each of the three electric instruments. Conclusions The results suggest that patients who are not adept at manual toothbrushing may potentially improve their removal of plaque from the fitting surfaces of FDPs by using electric toothbrushes.
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Affiliation(s)
- Toru Maeda
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan.
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Sirapat Thongpoung
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Akiko Tamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Fumiko Aonuma
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, 2-6-1 Manazuru, Kokurakita-Ku, Kitakyushu City, Fukuoka, 803-8580, Japan
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21
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Kusuda Y, Kondo Y, Miyagi Y, Munemasa T, Hori Y, Aonuma F, Tsuka S, Mukaibo T, Masaki C, Hosokawa R. Long-term dexamethasone treatment diminishes store-operated Ca 2+ entry in salivary acinar cells. Int J Oral Sci 2019; 11:1. [PMID: 30602784 PMCID: PMC6315037 DOI: 10.1038/s41368-018-0031-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 05/10/2018] [Accepted: 05/14/2018] [Indexed: 11/09/2022] Open
Abstract
Corticosteroids are used in the treatment of many diseases; however, they also induce various side effects. Dexamethasone is one of the most potent corticosteroids, and it has been reported to induce the side effect of impaired salivary gland function. This study aimed to evaluate the effects of dexamethasone on mouse submandibular gland function to gain insight into the mechanism of dexamethasone-induced salivary hypofunction. The muscarinic agonist carbachol (CCh) induced salivary secretion and was not affected by short-term dexamethasone treatment but was decreased following long-term dexamethasone administration. The expression levels of the membrane proteins Na+-K+-2Cl- cotransporter, transmembrane member 16A, and aquaporin 5 were comparable between the control and long-term dexamethasone treatment groups. The CCh-induced increase in calcium concentration was significantly lower in the presence of extracellular Ca2+ in the long-term dexamethasone treatment group compared to that in the control group. Furthermore, CCh-induced salivation in the absence of extracellular Ca2+ and Ca2+ ionophore A23187-induced salivation was comparable between the control and long-term dexamethasone treatment groups. Moreover, salivation induced by the Ca2+-ATPase inhibitor thapsigargin was diminished in the long-term dexamethasone treatment group. In summary, these results demonstrate that short-term dexamethasone treatment did not impair salivary gland function, whereas long-term dexamethasone treatment diminished store-operated Ca2+ entry, resulting in hyposalivation in mouse submandibular glands.
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Affiliation(s)
- Yuichiro Kusuda
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan.
| | - Yuta Miyagi
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Yusuke Hori
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Fumiko Aonuma
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka, 803-8580, Japan
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Yamazaki S, Masaki C, Nodai T, Tamura A, Tsuka S, Mukaibo T, Kondo Y, Ono K, Hosokawa R. OSC16: Effects of Streptozotocin-induced Diabetes Mellitus on Peri-implantitis. J Indian Prosthodont Soc 2018; 18:S13-S14. [PMID: 30532407 PMCID: PMC6238428 DOI: 10.4103/0972-4052.244606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Seiya Yamazaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Tomotaka Nodai
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Akiko Tamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Kentaro Ono
- Division of Physiology, Kyushu Dental University, Kitakyushu, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
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23
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Kondo Y, Masaki C, Tamura A, Tsuka S, Mukaibo T, Iwasaki M, Ansai T, Hosakawa R. OSNC5: Ten-Year Survival of Immediate-Loading Implants in Fully Edentulous Maxilla in the Asian Population: A Multilevel Analysis. J Indian Prosthodont Soc 2018; 18:S30-S31. [PMID: 30532442 PMCID: PMC6238472 DOI: 10.4103/0972-4052.244645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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24
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Fukahori S, Kondo Y, Tamura A, Tsuka S, Mukaibo T, Masaki C, Hosokawa R. OSC35: Relationship between Occlusal Support and Total Dietary Fiber Intake. J Indian Prosthodont Soc 2018; 18:S22-S23. [PMID: 30532426 PMCID: PMC6238445 DOI: 10.4103/0972-4052.244626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Shinji Fukahori
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Akiko Tamura
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
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Abstract
Mutations in the ectodysplasin A gene ( EDA) cause X-LHED (X-linked hypohidrotic ectodermal dysplasia), the most common human form of ectodermal dysplasia. Defective EDA signaling is linked to hypoplastic development of epithelial tissues, resulting in hypotrichosis, hypodontia, hypohidrosis, and xerostomia. The primary objective of the present study was to better understand the salivary gland dysfunction associated with ectodermal dysplasia using the analogous murine disorder. The salivary flow rate and ion composition of the 3 major salivary glands were determined in adult Eda-deficient Tabby hemizygous male (Ta/Y) and heterozygous female (Ta/X) mice. Submandibular and sublingual glands of Eda-mutant mice were smaller than wild-type littermates, while parotid gland weight was not significantly altered. Fluid secretion by the 3 major salivary glands was essentially unchanged, but the decrease in submandibular gland size was associated with a dramatic loss of ducts in Ta/Y and Ta/X mice. Reabsorption of Na+ and Cl-, previously linked in salivary glands to Scnn1 Na+ channels and Cftr Cl- channels, respectively, was markedly reduced at high flow rates in the ex vivo submandibular glands of Ta/Y mice (~60%) and, to a lesser extent, Ta/X mice (Na+ by 14%). Consistent with decreased Na+ reabsorption in Ta/Y mice, quantitative polymerase chain reaction analysis detected decreased mRNA expression for Scnn1b and Scnn1g, genes encoding the β and γ subunits, respectively. Moreover, the Na+ channel blocker amiloride significantly inhibited Na+ and Cl- reabsorption by wild-type male submandibular glands to levels comparable to those observed in Ta/Y mice. In summary, fluid secretion was intact in the salivary glands of Eda-deficient mice but displayed marked Na+ and Cl- reabsorption defects that correlated with the loss of duct cells and decreased Scnn1 Na+ channel expression. These results provide a likely mechanism for the elevated NaCl concentration observed in the saliva of affected male and female patients with X-LHED.
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Affiliation(s)
- T. Mukaibo
- Secretory Mechanisms and Dysfunctions Section,
National Institute of Dental and Craniofacial Research, National Institutes of Health,
Bethesda, MD, USA
- Department of Oral Reconstruction and
Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - T. Munemasa
- Secretory Mechanisms and Dysfunctions Section,
National Institute of Dental and Craniofacial Research, National Institutes of Health,
Bethesda, MD, USA
- Department of Oral Reconstruction and
Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - C. Masaki
- Department of Oral Reconstruction and
Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - C.Y. Cui
- Laboratory of Genetics and Genomics, National
Institute of Aging, National Institutes of Health, Baltimore, MD, USA
| | - J.E. Melvin
- Secretory Mechanisms and Dysfunctions Section,
National Institute of Dental and Craniofacial Research, National Institutes of Health,
Bethesda, MD, USA
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26
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Mukaibo T, Munemasa T, George AT, Tran DT, Gao X, Herche JL, Masaki C, Shull GE, Soleimani M, Melvin JE. The apical anion exchanger Slc26a6 promotes oxalate secretion by murine submandibular gland acinar cells. J Biol Chem 2018; 293:6259-6268. [PMID: 29530983 PMCID: PMC5925796 DOI: 10.1074/jbc.ra118.002378] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/08/2018] [Indexed: 12/15/2022] Open
Abstract
The solute carrier family 26 (SLC26) gene family encodes at least 10 different anion exchangers. SLC26 member 6 (SLC26A6 or CFEX/PAT-1) and the cystic fibrosis transmembrane conductance regulator (CFTR) co-localize to the apical membrane of pancreatic duct cells, where they act in concert to drive HCO3- and fluid secretion. In contrast, in the small intestine, SLC26A6 serves as the major pathway for oxalate secretion. However, little is known about the function of Slc26a6 in murine salivary glands. Here, RNA sequencing-based transcriptional profiling and Western blots revealed that Slc26a6 is highly expressed in mouse submandibular and sublingual salivary glands. Slc26a6 localized to the apical membrane of salivary gland acinar cells with no detectable immunostaining in the ducts. CHO-K1 cells transfected with mouse Slc26a6 exchanged Cl- for oxalate and HCO3-, whereas two other anion exchangers known to be expressed in salivary gland acinar cells, Slc4a4 and Slc4a9, mediated little, if any, Cl-/oxalate exchange. Of note, both Cl-/oxalate exchange and Cl-/HCO3- exchange were significantly reduced in acinar cells isolated from the submandibular glands of Slc26a6-/- mice. Oxalate secretion in submandibular saliva also decreased significantly in Slc26a6-/- mice, but HCO3- secretion was unaffected. Taken together, our findings indicate that Slc26a6 is located at the apical membrane of salivary gland acinar cells, where it mediates Cl-/oxalate exchange and plays a critical role in the secretion of oxalate into saliva.
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Affiliation(s)
- Taro Mukaibo
- From the Secretory Mechanisms and Dysfunctions Section and
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Takashi Munemasa
- From the Secretory Mechanisms and Dysfunctions Section and
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Alvin T George
- From the Secretory Mechanisms and Dysfunctions Section and
| | - Duy T Tran
- Biological Chemistry Section, NIDCR, National Institutes of Health, Bethesda, Maryland 20892
| | - Xin Gao
- From the Secretory Mechanisms and Dysfunctions Section and
- the Joint Institute for Food Safety and Applied Nutrition, University of Maryland, College Park, Maryland 20742, and
| | - Jesse L Herche
- From the Secretory Mechanisms and Dysfunctions Section and
| | - Chihiro Masaki
- the Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Fukuoka 803-8580, Japan
| | - Gary E Shull
- Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | | | - James E Melvin
- From the Secretory Mechanisms and Dysfunctions Section and
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27
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Munemasa T, Mukaibo T, Kondo Y, Masaki C, Kusuda Y, Miyagi Y, Tsuka S, Hosokawa R, Nakamoto T. Salivary gland hypofunction in KK-A y type 2 diabetic mice. J Diabetes 2018; 10:18-27. [PMID: 28299899 DOI: 10.1111/1753-0407.12548] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/27/2017] [Accepted: 03/12/2017] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Hypofunction of different organs in the body is associated with diabetes, including in the oral cavity. Diabetes is often associated with xerostomia, but the underlying mechanism is not well characterized. Thus, the mechanisms underlying diabetes-induced xerostomia were investigated in this study in KK-A y mice as an experimental model of type 2 diabetes. METHODS The mechanisms involved in diabetes-induced xerostomia were investigated using the ex vivo glandular perfusion technique, histological analysis, and immunohistochemical and intracellular signaling analyses. RESULTS Ex vivo submandibular gland secretions from KK-Ay mice decreased by 30% following stimulation with 0.3 μmol/L carbachol (CCh), a cholinergic agonist. Acinar cell weight was comparable between KK-Ay and control mice, whereas duct cell weight was significantly greater in KK-Ay mice. Concentrations of Na+ and Cl- in the secreted saliva decreased significantly in KK-Ay mice, supporting the finding of increased ductal tissue in KK-Ay mice. Immunohistochemistry revealed no significant differences between KK-Ay and control mice in terms of the expression of Cl- and water channels, Na+ -K+ -2Cl- cotransporters, and membrane proteins critical for fluid secretion. Cellular signaling analysis revealed that the increase in [Ca2+ ]i in response to 0.3 μmol/L CCh was reduced by 30% in KK-Ay mice, although there was no significant difference in the thapsigargin (1.0 μmol/L)-induced increase in store-depleted calcium between KK-Ay and control mice. CONCLUSIONS These results demonstrate that submandibular fluid secretion is diminished in KK-Ay mice because of a diminished increase in [Ca2+ ]i . Duct cell weight increased in KK-Ay mice, possibly leading to increased ion reabsorption and thus decreased Na+ and Cl- concentrations in the secreted saliva.
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Affiliation(s)
- Takashi Munemasa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Taro Mukaibo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yusuke Kondo
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Chihiro Masaki
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yuichiro Kusuda
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Yuta Miyagi
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Shintaro Tsuka
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Ryuji Hosokawa
- Division of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
| | - Tetsuji Nakamoto
- Department of Prosthodontics, Matsumoto Dental University, Nagano, Japan
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28
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Abstract
OBJECTIVE To evaluate the utility of vacuum-pressed, BruxChecker® sheets for the diagnosis of sleep bruxism. METHODS Twenty subjects participated in this study. Tooth contact during sleep was recorded using a 0.1 mm-thick polyvinyl chloride sheet called BruxChecker®. The area of the BruxChecker® in which the red dye was removed was measured. In addition, the EMG activity of the masseter muscle during sleep was recorded. The numbers of bruxism bursts and episodes were counted, and their correlations with the peeled area of the red dye on the BruxChecker® were evaluated. RESULTS The number of bruxism bursts and episodes/hr significantly correlated with the peeled area at all cut-off values. The peeled area significantly correlated with the number of phasic type bruxism episodes but not with tonic or mixed type bruxism episodes. DISCUSSION Since the BruxChecker® peeled area reflected phasic type sleep bruxism, the sheets may be useful in sleep bruxism screening.
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Affiliation(s)
- Hiromichi Hokama
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
| | - Chihiro Masaki
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
| | - Taro Mukaibo
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
| | - Shintaro Tsuka
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
| | - Yusuke Kondo
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
| | - Ryuji Hosokawa
- a Department of Oral Reconstruction and Rehabilitation , Kyushu Dental University , Fukuoka , Japan
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29
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Iwanabe Y, Masaki C, Tamura A, Tsuka S, Mukaibo T, Kondo Y, Hosokawa R. The effect of low-intensity pulsed ultrasound on wound healing using scratch assay in epithelial cells. J Prosthodont Res 2016; 60:308-314. [DOI: 10.1016/j.jpor.2016.03.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/07/2016] [Accepted: 03/15/2016] [Indexed: 10/22/2022]
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30
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Ganeko K, Masaki C, Shibata Y, Mukaibo T, Kondo Y, Nakamoto T, Miyazaki T, Hosokawa R. Bone Aging by Advanced Glycation End Products. J Dent Res 2015; 94:1684-90. [DOI: 10.1177/0022034515602214] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The quality and quantity of mandibular bone are essential prerequisites for osseointegrated implants. Only the Hounsfield unit on preoperative computed tomography is currently used as a clinical index. Nevertheless, a considerable mismatch occurs between bone quality and the Hounsfield unit. Loss of bone toughness during aging has been accepted based on empirical evidence, but this concept is unlikely evidence based at the level of mechanical properties. Nonenzymatic bone matrix cross-links associated with advanced glycation end products predominate as a consequence of aging. Thus, loss of tissue integrity could diminish the bone toughening mechanism. Here, we demonstrate an impaired bone toughening mechanism caused by mimicking aging in rabbits on a methionine-rich diet, which enabled an enhanced nonenzymatically cross-linked bone matrix. A 3-point bending test revealed a greater reduction in femoral fracture resistance in rabbits on a methionine-rich diet, despite higher maximum and normalized breaking forces (287.3 N and 88.1%, respectively), than in rabbits on a normal diet (262.2 N and 79.7%, respectively). In situ nanoindentation on mandibular cortical bone obtained from rabbits on a methionine-rich diet did not enable strain rate–dependent stiffening and consequent large-dimensional recovery during rapid loading following constant displacement after a rapid-load indentation test as compared with those in rabbits on a normal diet. Such nanoscale structure-function relationships dictate resistance to cracking propagation at the material level and allow for the overall bone toughening mechanism to operate under large external stressors. The strain-dependent stiffening was likely associated with strain-energy transfer to the superior cross-linked bone matrix network of the normal diet, while the reduction in the enzymatically cross-linked matrix in bone samples from rabbits on a methionine-rich diet likely diminished the intrinsic bone toughening mechanism. The present study also provides a precise protocol for evaluating bone mechanical properties at the material level based on observations from a series of nanoindentation experiments.
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Affiliation(s)
- K. Ganeko
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - C. Masaki
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Y. Shibata
- Division of Biomaterials and Engineering, Department of Conservative Dentistry, Showa University School of Dentistry, Tokyo, Japan
| | - T. Mukaibo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - Y. Kondo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - T. Nakamoto
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
| | - T. Miyazaki
- Division of Biomaterials and Engineering, Department of Conservative Dentistry, Showa University School of Dentistry, Tokyo, Japan
| | - R. Hosokawa
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu, Japan
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31
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Masaki C, Nakamoto T, Mukaibo T, Kondo Y, Hosokawa R. Strategies for alveolar ridge reconstruction and preservation for implant therapy. J Prosthodont Res 2015; 59:220-8. [PMID: 26022542 DOI: 10.1016/j.jpor.2015.04.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 04/21/2015] [Accepted: 04/23/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE In dental implant treatment, ridge preservation and immediate or early implant placement are recommended to minimize bone resorption after tooth extraction and achieve esthetic outcomes. However, there is no consensus concerning the efficacy of this surgical method. There is also no consensus on the efficacy of bone and soft tissue grafts and surgical methods for alveolar ridge reconstruction. STUDY SELECTION This paper reports ridge alteration in the anterior maxilla after tooth extraction, and summarizes the efficacy of various ridge preservation methods and immediate or early implant placement as alveolar ridge preservation methods to minimize bone resorption after tooth extraction. The advantages and complications of alveolar ridge reconstruction methods, and the efficacy and surgical method of soft tissue graft are reviewed. RESULTS The anterior maxilla is in the esthetic zone, and the thickness of the bone on the labial side around the natural tooth is less than 1mm in many cases. Therefore, it is impossible to prevent bone resorption completely, even if ridge preservation and immediate or early implant placement are performed after tooth extraction. It is necessary to obtain stable and long-term esthetics by combining connective tissue and free gingival grafts, in addition to hard tissue augmentation. CONCLUSIONS It is important to consider the burden and level of satisfaction of patients, such as in terms of donor site morbidity in hard and soft tissue grafting, and to pay attention to appropriate indications to avoid overtreatment.
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Affiliation(s)
- Chihiro Masaki
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan.
| | - Tetsuji Nakamoto
- Department of Prosthodontics, Graduate School of Oral & Maxillofacial Biology, School of Dentistry, Matsumoto Dental University, Japan
| | - Taro Mukaibo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Yusuke Kondo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
| | - Ryuji Hosokawa
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Japan
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32
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Morino M, Masaki C, Seo Y, Mukai C, Mukaibo T, Kondo Y, Shiiba S, Nakamoto T, Hosokawa R. Non-randomized controlled prospective study on perioperative levels of stress and dysautonomia during dental implant surgery. J Prosthodont Res 2014; 58:177-83. [PMID: 24981241 DOI: 10.1016/j.jpor.2014.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/12/2014] [Accepted: 03/17/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE The purpose of this study was to compare pre- and postoperative autonomic activities and changes in salivary stress biomarkers between patients who received only local anesthesia and those who received local anesthesia together with intravenous sedation in dental implant surgery. METHODS A total of 21 patients were enrolled in this non-randomized controlled prospective study; 7 subjects underwent implant surgery under local anesthesia with intravenous sedation and 14 subjects underwent surgery under only local anesthesia. Stress was evaluated by measuring salivary levels of chromogranin A (CgA) and a spectral analysis of heart rate variability (HRV) at baseline (on a day other than the day of surgery), 1h preoperatively, and 1h postoperatively. HRV analysis yields low- (LF) and high-frequency (HF) components, the LF/HF ratio, and the component coefficient of variance (CCV[HF]), which provide indices of sympathetic and parasympathetic regulatory activity. RESULTS CgA levels were significantly higher (p<0.05) at baseline in patients who received sedation than those who did not, but CgA levels did not differ prior to surgery. Also, the values of most parameters, including LF, HF, LF/HF (L/H), and CCV(HF), did not significantly differ between groups or among the three time points. Only ΔL/H and ΔCCV(HF) were significantly lower (p<0.05) at 1h preoperatively in patients who received sedation than those who received only local anesthesia. CONCLUSIONS CgA levels were high in both groups immediately before surgery, and thus CgA values immediately before surgery may not be a reliable indicator of the need for intravenous sedation. Also, spectral analysis of HRV, especially ΔL/H and ΔCCV(HF), could be useful for assessing tension and anxiety.
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Affiliation(s)
- Miyuki Morino
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Chihiro Masaki
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Yoshinori Seo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Chisato Mukai
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Taro Mukaibo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Yusuke Kondo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Shunji Shiiba
- Department of Dental Anesthesiology, Kyushu Dental University, Japan
| | - Tetsuji Nakamoto
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan
| | - Ryuji Hosokawa
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Graduate School, Japan.
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33
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Misumi S, Nakamoto T, Kondo Y, Mukaibo T, Masaki C, Hosokawa R. A prospective study of changes in oral health-related quality of life during immediate function implant procedures for edentulous individuals. Clin Oral Implants Res 2014; 26:696-700. [PMID: 24666378 DOI: 10.1111/clr.12371] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of this prospective clinical study was to evaluate longitudinal changes in oral health-related quality of life (OHRQoL) attributable to fixed dental prostheses during All-on-4(®) treatment in one or both jaws. MATERIALS AND METHODS Ten patients underwent placement of four or six endosteal dental implants on the basis of the All-on-4(®) treatment concept in the edentulous maxilla or both jaws and immediate loading with acrylic interim prostheses. The prostheses were replaced after 3-6 months, and definitive prostheses with titanium framework and reinforced resin facing were fixed after another 5 months or more. The subjects completed the shortened Japanese version of the Oral Health Impact Profile (OHIP-J14) before the surgery (T0), 1 week after the initial (T1) and secondary (T2) interim prostheses were placed, and 3 months after definitive prosthesis placement (T3). Complete data of nine subjects were analyzed with the Wilcoxon signed-rank test. RESULTS The total OHIP-J14 score significantly reduced only at T3 (P < 0.05). "Functional limitation," "physical pain," "physical disability," and "psychological disability" scores significantly decreased at T3, and "psychological discomfort" scores also significantly dropped at T2. "Social disability" and "handicap" scores remained unchanged throughout. CONCLUSION Fixed definitive prostheses with metal framework are more effective than fixed all-acrylic prostheses in improving OHRQoL during All-on-4(®) treatment.
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Affiliation(s)
- Saori Misumi
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
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34
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Kidokoro M, Nakamoto T, Mukaibo T, Kondo Y, Munemasa T, Imamura A, Masaki C, Hosokawa R. Na(+)-K(+)-2Cl(-) cotransporter-mediated fluid secretion increases under hypotonic osmolarity in the mouse submandibular salivary gland. Am J Physiol Renal Physiol 2014; 306:F1155-60. [PMID: 24623142 DOI: 10.1152/ajprenal.00709.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Water-handling epithelia are sensitive to the osmotic environment. In this study, the effects of a hypo-osmotic challenge on carbachol (CCh)-induced fluid secretion was investigated using an ex vivo submandibular gland perfusion technique and intracellular pH and Ca(2+) measurements. The osmolality of the perfusion solution was altered to examine the response of the gland to a hypotonic challenge. The flow rate was increased by 34% with a 30% hypotonic solution (225 mosmol/kgH2O), although the Ca(2+) response was unchanged. The lowering of the external Cl(-) by 50% abolished this increase in the 30% hypotonic solution. Furthermore, bumetanide, an inhibitor of the Na(+)-K(+)-2Cl(-) cotransporter (NKCC1), completely inhibited the fluid secretion increase caused by the 30% hypotonic solution, and both the total amount of fluid and the flow rate were identical to those of the isotonic solution. This finding was confirmed by measuring the NKCC1 bumetanide-dependent NH4 (+) transport; Na(+)-K(+)-2Cl(-) transport was upregulated >40% by a 30% hypotonic challenge. Therefore, the increase in CCh-induced fluid secretion in response to hypotonic conditions can be attributed, to a large extent, to the specific activation of the NKCC1.
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Affiliation(s)
- Manami Kidokoro
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Tetsuji Nakamoto
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Taro Mukaibo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Yusuke Kondo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Takashi Munemasa
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Atsushi Imamura
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Chihiro Masaki
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
| | - Ryuji Hosokawa
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Kitakyushu City, Fukuoka, Japan
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Murakami T, Masaki C, Takahashi H, Makino M, Mukaibo T, Kondo Y, Nakamoto T, Hosokawa R. Sleep bruxism is affected by peripheral benzodiazepine receptor gene polymorphisms. J Stomat Occ Med 2014. [DOI: 10.1007/s12548-013-0101-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Takahashi H, Masaki C, Makino M, Yoshida M, Mukaibo T, Kondo Y, Nakamoto T, Hosokawa R. Management of sleep-time masticatory muscle activity using stabilisation splints affects psychological stress. J Oral Rehabil 2013; 40:892-9. [PMID: 24237357 DOI: 10.1111/joor.12110] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/05/2013] [Indexed: 11/28/2022]
Abstract
To treat sleep bruxism (SB), symptomatic therapy using stabilisation splints (SS) is frequently used. However, their effects on psychological stress and sleep quality have not yet been examined fully. The objective of this study was to clarify the effects of SS use on psychological stress and sleep quality. The subjects (11 men, 12 women) were healthy volunteers. A crossover design was used. Sleep measurements were performed for three consecutive days or longer without (baseline) or with an SS or palatal splint (PS), and data for the final day were evaluated. We measured masseter muscle activity during sleep using portable electromyography to evaluate SB. Furthermore, to compare psychological stress before and after sleep, assessments were made based on STAI-JYZ and the measurement of salivary chromogranin A. To compare each parameter among the three groups (baseline, SS and PS), Friedman's and Dunn's tests were used. From the results of the baseline measurements, eight subjects were identified as high group and 15 as low group. Among the high group, a marked decrease in the number of bruxism events per hour and an increase in the difference in the total STAI Y-1 scores were observed in the SS group compared with those at baseline (P < 0·05). No significant difference was observed in sleep stages. SS use may be effective in reducing the number of SB events, while it may increase psychological stress levels, and SS use did not apparently influence sleep stages.
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Affiliation(s)
- H Takahashi
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental University, Fukuoka, Japan
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Mukaibo T, Nakamoto T, Kondo Y, Kidokoro M, Imamura A, Masaki C, Hosokawa R. Thermal influence of saliva secretion <i>ex vivo</i> in the mouse submandibular gland. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojst.2013.31015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kondo Y, Nakamoto T, Mukaibo T, Kidokoro M, Masaki C, Hosokawa R. Cevimeline-induced monophasic salivation from the mouse submandibular gland: decreased Na+ content in saliva results from specific and early activation of Na+/H+ exchange. J Pharmacol Exp Ther 2011; 337:267-74. [PMID: 21239510 DOI: 10.1124/jpet.110.174946] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cevimeline and pilocarpine are muscarinic agonists used clinically to treat dry mouth. In this study, we explored fluid secretion from mouse submandibular glands to determine the mechanism of cevimeline, pilocarpine, and an experimentally used agent carbachol. Cevimeline evoked almost the same amount of secretion at concentrations from 30 μM to 1 mM. Pilocarpine also induced secretion at a concentration as low as 1 μM and was the most powerful secretagogue at 10 μM. Secretion was induced by carbachol at 0.1 μM, with maximum secretion at 1.0 μM. Cevimeline induced monophasic secretion at all concentrations tested, whereas higher concentrations of pilocarpine and carbachol induced secretion with variable kinetics, i.e., an initial transient high flow rate, followed by decreased secretion after 2 to 3 min. In the presence of an epithelial Na(+) channel blocker, amiloride, neither carbachol nor pilocarpine affected the Na(+) level of secreted saliva; however, it significantly increased the Na(+) content of cevimeline-induced saliva. The intracellular Ca(2+) response of acinar cells was almost identical among all three agents, although recovery after drug removal was slower for cevimeline and pilocarpine. A profound decrease in intracellular pH was observed during pilocarpine and carbachol treatment, whereas intracellular acidification induced by cevimeline was only seen in the presence of a Na(+)/H(+) exchange inhibitor. When external HCO(3)(-) was removed, cevimeline-induced saliva significantly decreased. These findings suggest that cevimeline specifically activates Na(+)/H(+) exchange and may promote Na(+) reabsorption by stabilizing epithelial sodium channel activity.
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Affiliation(s)
- Yusuke Kondo
- Department of Oral Reconstruction and Rehabilitation, Kyushu Dental College, Kitakyushu City, Japan
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